Search results for: expected damage cost

Authors: Gurlal Singh, Rupinder Singh

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The possible role of the engine brake is to convert a power-producing engine into a power-absorbing retarding mechanism. In this braking system, exhaust gas (EG) from the internal combustion (IC) engines is used to operate air brake in the automobiles. Airbrake is most used braking system in vehicles. In the proposed model, instead of air brake, EG is used to operate the brake lever and stored in a specially designed tank. This pressure of EG is used to operate the pneumatic cylinder and brake lever. Filters used to remove the impurities from the EG, then it is allowed to store in the tank. Pressure relief valve is used to achieve a specific pressure in the tank and helps to avoid further damage to the tank as well as in an engine. The petrol engine is used in the proposed EG braking system. The petrol engine is chosen initially because it produces less impurity in the exhaust than diesel engines. Moreover, exhaust brake system (EBS) for the Diesel engines is composed of gate valve, pneumatic cylinder and exhaust brake valve with the on-off solenoid. Exhaust brake valve which is core component of EBS should have characteristics such as high reliability and long life. In a diesel engine, there is butterfly valve in exhaust manifold connected with solenoid switch which is used to on and off the butterfly valve. When butterfly valve closed partially, then the pressure starts built up inside the exhaust manifold and cylinder that actually resist the movement of piston leads to crankshaft getting stops resulting stopping of the flywheel. It creates breaking effect in a diesel engine. The exhaust brake is a supplementary breaking system to the service brake. It is noted that exhaust brake increased 2-3 fold the life of service brake may be due to the creation of negative torque which retards the speed of the engine. More study may also be warranted for the best suitable design of exhaust brake in a diesel engine.

Keywords: exhaust gas, automobiles, solenoid, airbrake

Procedia PDF Downloads 265

Authors: Karla D. Vazquez-Valdez, Bradley P. Wynne

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In the last decades manufacturing needs have been changing, leading to the study of manufacturing methods that were underdeveloped, such as incremental forming processes like shear forming. These processes use rotating tools in constant local contact with the workpiece, which is often also rotating, to generate shape. This means much lower loads to forge large parts and no need for expensive special tooling. Potential has already been established by demonstrating manufacture of high-value products, e.g., turbine and satellite parts, with high dimensional accuracy from difficult to manufacture materials. Thus, huge opportunities exist for these processes to replace the current method of manufacture for a range of high value components, e.g., eliminating lengthy machining, reducing material waste and process times; or the manufacture of a complicated shape without the development of expensive tooling. However, little is known about the exact deformation conditions during processing and why certain materials are better than others for shear forming, leading to a lot of trial and error before production. Three alloys were used for this study: Ti-54M, Jethete M154, and IN718. General Microscopy and Electron Backscatter Diffraction (EBSD) were used to measure strains and orientation maps during shear forming. A Design of Experiments (DOE) analysis was also made in order to understand the impact of process parameters in the properties of the final workpieces. Such information was the key to develop a reliable Finite Element Method (FEM) model that closely resembles the deformation paths of this process. Finally, the potential of these three materials to be shear spun was studied using the FEM model and their Forming Limit Diagram (FLD) which led to the development of a rough methodology for testing the shear spinnability of various metals.

Keywords: shear forming, damage, principal strains, forming limit diagram

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Authors: N. F. Hamid, A. Kipar, J. Stewart, D. J. Antoine, B. K. Park, D. P. Williams

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Acetaminophen (APAP) is a widely used analgesic that is safe at therapeutic doses. The mouse model of APAP has been extensively used for studies on pathogenesis and intervention of drug induced liver injury based on the CytP450 mediated formation of N-acetyl-p-benzo-quinoneimine and, more recently, as model for mechanism based biomarkers. Delay of the fasted CD1 mice to rebound to the basal level of hepatic GSH compare to fed mice is reported in this study. Histologically, 15 hours fasted mice prior to APAP treatment leading to overall more intense cell loss with no evidence of apoptosis as compared to non-fasted mice, where the apoptotic cells were clearly seen on cleaved caspase-3 immunostaining. After 15 hours post APAP administration, hepatocytes underwent stage of recovery with evidence of mitotic figures in fed mice and return to completely no histological difference to control at 24 hours. On the contrary, the evidence of ongoing cells damage and inflammatory cells infiltration are still present on fasted mice until the end of the study. To further measure the regenerative capacity of the hepatocytes, the inflammatory mediators of cytokines that involved in the progression or regression of the toxicity like TNF-α and IL-6 in liver and spleen using RT-qPCR were also included. Yet, quantification of proliferating cell nuclear antigen (PCNA) has demonstrated the time for hepatic regenerative in fasted is longer than that to fed mice. Together, these data would probably confirm that fasting prior to APAP treatment does not only modulate liver injury, but could have further effects to delay subsequent regeneration of the hepatocytes.

Keywords: acetaminophen, liver, proliferating cell nuclear antigen, regeneration, apoptosis

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Authors: M. Koray Cetin, Mehmet Mert

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The purpose of the study is to examine impacts on tourism revenues of the exchange rate and country overall security level. There are numerous studies that examine the bidirectional relation between macroeconomic factors and tourism revenues and tourism demand. Most of the studies support the existence of impact of tourism revenues on growth rate but not vice versa. Few studies examine the impact of factors like real exchange rate or purchasing power parity on the tourism revenues. In this context, firstly impact of real exchange rate on tourism revenues examination is aimed. Because exchange rate is one of the main determinants of international tourism services price in guests currency unit. Another determinant of tourism demand for a country is country’s overall security level. This issue can be handled in the context of the relationship between tourism revenues and overall security including turmoil, terrorism, border problem, political violence. In this study, factors are handled for several countries which have tourism revenues on a certain level. With this structure, it is a panel data, and it is evaluated with panel data analysis techniques. Panel data have at least two dimensions, and one of them is time dimensions. The panel data analysis techniques are applied to data gathered from Worldbank data web page. In this study, it is expected to find impacts of real exchange rate and security factors on tourism revenues for the countries that have noteworthy tourism revenues.

Keywords: exchange rate, panel data analysis, security, tourism revenues

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Authors: A. Boveiri Monji, H. Yousefnia, M. Haji Hosseini, S. Zolghadri

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A clean spectrophotometric method for the determination of hafnium by using a green reagent, acidic extract of Ficus carica tree leaves is developed. In 6-M hydrochloric acid, hafnium reacts with this reagent to form a yellow product. The formed product shows maximum absorbance at 421 nm with a molar absorptivity value of 0.28 × 104 l mol⁻¹ cm⁻¹, and the method was linear in the 2-11 µg ml⁻¹ concentration range. The detection limit value was found to be 0.312 µg ml⁻¹. Except zirconium and iron, the selectivity was good, and most of the ions did not show any significant spectral interference at concentrations up to several hundred times. The proposed method was green, simple, low cost, and selective.

Keywords: spectrophotometric determination, Ficus caricatree leaves, synthetic reagents, hafnium

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Authors: Tasaduk Musood

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In the dynamic landscape of higher education, intra-regional migration within Kashmir represents a complex interplay of influential elements. This qualitative research study aims to explore and analyze the multifaceted factors that significantly shape the patterns and motivations driving students' migration within the region. The study employed a qualitative research approach. The research is carried out with a sample of 60 participants, consisting of 30 male and 30 female students selected from various higher education institutions in the Punjab region. Through self-structured interviews and thematic analysis, the research unravels the underlying drivers, aspirations, challenges, and opportunities that underpin the phenomenon of intra-regional migration in the Kashmiri higher education landscape. The results of this study are expected to offer valuable insights for policymakers, educational institutions, and stakeholders to better understand, address, and potentially enhance the experiences and outcomes of shareholders of students engaged in intra-regional mobility within Kashmir's higher education domain. This study's findings aim to contribute significantly to the existing body of knowledge surrounding intra-regional migration within Kashmir's higher education landscape, offering a nuanced understanding of the drivers behind student mobility. Ultimately, this research endeavors to facilitate more informed and effective decision-making in addressing the evolving dynamics of intra-regional migration in Kashmir's higher education sector.

Keywords: intra-regional migration, student migration patterns, student mobility, higher education, kashmir

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Authors: Mohammad Idrees Yusofzai, Hirobata Yasuhiro, Matsuo Kojiro

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Kabul is the capital of Afghanistan. It is the focal point of educational, industrial, etc. of Afghanistan. Additionally, the population of Kabul has grown recently and will increase because of return of refugees and shifting of people from other province to Kabul city. However, this increase in population, the issues of urban congestion and other related problems of urban transportation in Kabul city arises. One of the problems is public transport (large buses) service and needs to be modified and enhanced especially large bus routes that are operating in each zone of the 22 zone of Kabul City. To achieve the above mentioned goal of improving public transport, Spatial Accessibility Analysis is one of the important attributes to assess the effectiveness of transportation system and urban transport policy of a city, because accessibility indicator as an alternative tool to support public policy that aims the reinforcement of sustainable urban space. The case study of this research compares the present model (present bus route) and the modified model of public transport. Furthermore, present model, the bus routes in most of the zones are active, however, with having low frequency and unpublished schedule, and accessibility result is analyzed in four cases, based on the variables of accessibility. Whereas in modified model all zones in Kabul is taken into consideration with having specified origin and high frequency. Indeed the number of frequencies is kept high; however, this number is based on the number of buses Millie Bus Enterprise Authority (MBEA) owns. The same approach of cases is applied in modified model to figure out the best accessibility for the modified model. Indeed, the modified model is having a positive impact in congestion level in Kabul city. Besides, analyses of person trip and trip distribution have been also analyzed because how people move in the study area by each mode of transportation. So, the general aims of this research are to assess the present movement of people, identify zones in need of public transport and assess equity level of accessibility in Kabul city. The framework of methodology used in this research is based on gravity analysis model of accessibility; besides, generalized cost (time) of travel and travel mode is calculated. The main data come from person trip survey, socio-economic characteristics, demographic data by Japan International Cooperation Agency, 2008, study of Kabul city and also from the previous researches on travel pattern and the remaining data regarding present bus line and routes have been from MBEA. In conclusion, this research explores zones where public transport accessibility level is high and where it is low. It was found that both models the downtown area or central zones of Kabul city is having high level accessibility. Besides, the present model is the most unfavorable compared with the modified model based on the accessibility analysis.

Keywords: accessibility, bus generalized cost, gravity model, public transportation network

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Authors: Akanksha Rohit, Ujjwala Godavarthi, Anshua Mukherjee

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Nanotechnology is one of the promising sustainable solutions in the era of miniaturization due to its multidisciplinary nature. The most interesting aspect about nanotechnology is its wide ranging applications from electronics to military and biomedical. It tries to connect individuals more closely to the environment. In this paper, concept of parasitic energy harvesting is used in designing nanogenerators using COMSOL 4.3 software. The output of the nanogenerator is optimized using following constraints: ease of availability of the material, fabrication process and cost of the material. The nanogenerator is optimized using ZnO based nanowires, PMMA as insulator and aluminum and silicon as metal electrodes. The energy harvested from the model can be used to power nanobots, several other biomedical sensors and eventually to replace batteries. Thus, advancements in this field can be very challenging but it is the future of the nano era.

Keywords: zinc oxide, piezoelectric, PMMA, parasitic energy harvesting, renewable energy engineering

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Authors: G. Khamooshian, A. Abbasimoshaei

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Different methods are used to stabilize the sticks, among which the method of knitting is commonly used. In recent years, the use of nailing for the stability of excavation has been considered much, which is providing sufficient stability and controlling the structural defects of the guardian, also reduces the cost of the operation. In addition, this method is more prominent in deep excavations than other methods. The purpose of this paper is to investigate the effect of groundwater level and soil type on the length and designing of nails. In this paper, analysis and modeling for vertical arena with constant depth and different levels of groundwater have been done. Also, by changing the soil resistance parameters and design of the nails, an optimum arrangement was made and the effect of changes in groundwater level and soil's type on the design of the nails, the maximum axial force mobilized in the nails and the confidence coefficient for the stability of the groove was examined.

Keywords: excavation, soil effects, nailing, hole analyzing

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Authors: Aichun Feng, Zhi-Min Chen, Jing Tang Xing

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A two-dimensional linear wave-body interaction problem can be solved using a desingularized integral method by placing free surface Rankine sources over calm water surface and satisfying boundary conditions at prescribed collocation points on the calm water surface. A new free-surface Rankine source distribution scheme, determined by the intersection points of free surface and body surface, is developed to reduce numerical computation cost. Associated with this, a new treatment is given to the intersection point. The present scheme results are in good agreement with traditional numerical results and measurements.

Keywords: source point distribution, panel method, Rankine source, desingularized algorithm

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Authors: Fharia Tilat Loba

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Studies show that there is a certain group of students who are more vulnerable to bullying due to their physical appearance, disability, sexual preference, race, and lack of social and behavioral skills. Students with autism spectrum disorders (ASD) are one of the most vulnerable groups among these at-risk groups. Researchers suggest that focusing on vulnerable groups of students who can be the target of bullying helps to understand the causes and patterns of aggression, which ultimately helps in structuring intervention programs to reduce bullying. Since Australia ratified the United Nations Convention on the Rights of Persons with Disabilities in 2006, it has been committed to providing an inclusive, safe, and effective learning environment for all children. In addition, the 2005 Disability Standards for Education seeks to ensure that students with disabilities can access and participate in education on the same basis as other students, covering all aspects of education, including harassment and victimization. However, bullying hinders students’ ability to fully participate in schooling. The proposed study aims to synthesize the notions of traditional bullying and cyberbullying and attempts to understand the experiences of students with ASD who are experiencing bullying in their schools. The proposed study will primarily focus on identifying the gaps between policy and practice related to bullying, and it will also attempt to understand the experiences of parents of students with ASD and professionals who have experience dealing with bullying at the school level in Australia. This study is expected to contribute to the theoretical knowledge of the bullying phenomenon and provide a reference for advocacy at the school, organization, and government levels.

Keywords: education policy, bullying, Australia, neurodiversity

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Authors: Veniamin Boiarkin, Bruno Bogaz Zarpelão, Muttukrishnan Rajarajan

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The manufacturing sector is a vital component of most economies, which leads to a large number of cyberattacks on organisations, whereas disruption in operation may lead to significant economic consequences. Adversaries aim to disrupt the production processes of manufacturing companies, gain financial advantages, and steal intellectual property by getting unauthorised access to sensitive data. Access to sensitive data helps organisations to enhance the production and management processes. However, the majority of the existing data-sharing mechanisms are either susceptible to different cyber attacks or heavy in terms of computation overhead. In this paper, a privacy-preserving data-sharing scheme for smart utilities is proposed. First, a customer’s privacy adjustment mechanism is proposed to make sure that end-users have control over their privacy, which is required by the latest government regulations, such as the General Data Protection Regulation. Secondly, a local differential privacy-based mechanism is proposed to ensure the privacy of the end-users by hiding real data based on the end-user preferences. The proposed scheme may be applied to different industrial control systems, whereas in this study, it is validated for energy utility use cases consisting of smart, intelligent devices. The results show that the proposed scheme may guarantee the required level of privacy with an expected relative error in utility.

Keywords: data-sharing, local differential privacy, manufacturing, privacy-preserving mechanism, smart utility

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Authors: R. Trad Khodja, A. Guessmi, R. Ghoul, A. Mahtout, S. A. Benbouali, M. A. Boulahlib

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Cranioplasty is a surgical act that aims to restore cranial bone losses in order to protect the brain from external aggressions and to improve the patient's aesthetic appearance. This objective can be achieved by taking advantage of the current technological development in computer science and biomechanics. The objective of this paper is to present an approach for the realization of high-precision biocompatible cranial implants using new 3D printing technologies at the lowest cost. The proposed method is to reproduce the missing part of the skull by referring to its healthy contralateral part. Once the model is validated by the neurosurgeons, a mold is 3D printed for the production of a biocompatible implant in Poly-Methyl-Methacrylate (PMMA) acrylic cement. Using this procedure, ten patients underwent this procedure with excellent aesthetic results.

Keywords: cranioplasty, cranial defect, PMMA, 3d printing, custom made implants

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Authors: Yunus Emre Karakaya, Sebahattin Devecioglu, Bilal Coban

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Today, information technology’s presence is felt in every field of life. Fields of education and sports sciences have their own share too. Especially developments in informatics technologies changed the perspectives of these fields. The altered technological conditions made distance education argumentative in these fields. Due to advantages distance education provides to students, they can access the desired education without concerns about time and place. Education facilities are seen to head for distance education in this manner and expedite the process. Distance education applications, which was first started to be applied in the mid-1800s, have been implemented in Turkey since 1970s and still continues today. In this study, the historical development of distance education in the world and Turkey and the problems athletes face in education were discussed. Accordingly, suggestions were made evaluating the importance and requirements of distance education in sports education facilities at higher education level. Additionally, Questions of “Is distance education important in sports education in Turkey?”, “What are the problems of athletes in the education field in Turkey?” and similar questions were attempted to be answered. Finally, in Turkey, distance sports education applications in universities should be launched to ensure that athletes’ educations are not deficit and unfinished. Within this framework, legal regulations should be implemented by “Council of Higher Education” to develop the distance sports education in Turkey and utilize distance education efficiently in solving the sports education problems. By ensuring the advancement of athletes with this method, it is expected for athletes to contribute to sports in the country in both government and the private sector in the medium and long terms. Individuals who participated in the distance sports education will set an example in extending the country’s youth to national and international fields.

Keywords: athletes, distance education, higher education, sports education, Turkey

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Authors: Amjad Almunyif, Amra Alhassni, Sultan Alhassan, Maryam Al Huwayz, Saud Alotaibi, Abdulaziz Almalki, Mohamed Henini

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The effect of rapid thermal annealing (RTA) on the optical properties of InAs quantum dots (QDs) grown at an As overpressure of 2x 10⁻⁶ Torr by molecular beam epitaxy (MBE) on (100) and (311)B GaAs substrates was investigated using photoluminescence (PL) technique. PL results showed that for the as-grown samples, the QDs grown on the high index plane (311)B have lower PL intensity and lower full width at half maximum (FWHM) than those grown on the conventional (100) plane. The latter demonstrates that the (311)B QDs have better size uniformity than (100) QDs. Compared with as-grown samples, a blue-shift was observed for all samples with increasing annealing temperature from 600°C to 700°C. For (100) samples, a narrowing of the FWHM was observed with increasing annealing temperature from 600°C to 700°C. However, in (311)B samples, the FWHM showed a different behaviour; it slightly increased when the samples were annealed at 600°C and then decreased when the annealing temperature increased to 700°C. As expected, the PL peak intensity for all samples increased when the laser excitation power increased. The PL peak energy temperature dependence showed a strong redshift when the temperature was increased from 10 K to 120 K. The PL peak energy exhibited an abnormal S-shape behaviour as a function of temperature for all samples. Most samples exhibited a significant enhancement in their activation energies when annealed at 600°C and 700°C, suggesting that annealing annihilated defects created during sample growth.

Keywords: RTA, QDs, InAs, MBE

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Authors: Junior George Martin

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The purpose of this study was to explore college instructors’ integration of technology in their content area curriculum. The instructors indicated that they were in need of additional training to successfully integrate technology in their subject areas. The findings point to the implementation of a proposed the Technological, Pedagogical, and Content Knowledge (TPACK) model professional development workshop to satisfactorily address the weaknesses of the instructors in technology integration. The professional development workshop is proposed as a rational solution to adequately address the instructors’ inability to the successful integration of technology in their subject area in an effort to improve their pedagogy. The intense workshop would last for 5 days and will be designed to provide instructors with training in areas such as a use of technology applications and tools, and using modern methodologies to improve technology integration. Exposing the instructors to the specific areas identified will address the weaknesses they demonstrated during the study. Professional development is deemed the most appropriate intervention based on the opportunities it provides the instructors to access hands-on training to overcome their weaknesses. The purpose of the TPACK professional development workshop will be to improve the competence of the instructors so that they are adequately prepared to integrate technology successfully in their curricula. At the end of the period training, the instructors are expected to adopt strategies that will have a positive impact on the learning experiences of the students.

Keywords: higher education, modern technology tools, professional development, technology integration

Procedia PDF Downloads 315

Authors: Davie G. Dave, Prisca H. Mugabe, Tonderai Mutibvu

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Globally, HWCs are on the rise. Such is the case with urban areas in Zimbabwe, yet little has been documented about it. This study was done to provide insights into the occurrence of human-wildlife conflicts in urban areas. The study was carried out in Harare, Bindura, Masvingo, Beitbridge, and Chiredzi to determine the cause, nature, extent, and frequency of occurrence of HWC, to determine the key wildlife species involved in conflicts and management practices done to combat wildlife conflicts in these areas. Several sampling techniques encompassing multi-stage sampling, stratified random, purposive, and simple random sampling were employed for placing residential areas into three strata according to population density, selecting residential areas, and selecting actual participants. Data were collected through a semi-structured questionnaire and key informant interviews. The results revealed that property destruction and crop damage were the most prevalent conflicts. Of the 15 animals that were cited, snakes, baboons, and monkeys were associated with the most conflicts. The occurrence of HWCs was mainly attributed to the increase in both animal and human populations. To curtail these HWCs, the local people mainly used non-lethal methods, whilst lethal methods were used by authorities for some of the reported cases. The majority of the conflicts were seasonal and less severe. There were growing concerns by respondents on the issues of wildlife conflicts, especially in those areas that had primates, such as Warren Park in Harare and Limpopo View in Beitbridge. There are HWCs hotspots in urban areas, and to ameliorate this, suggestions are that there is a need for a multi-action approach that includes general awareness campaigns on HWCs and land use planning that involves the creation of green spaces to ease wildlife management.

Keywords: human-wildlife conflicts, mitigation measures, residential areas, types of conflicts, urban areas

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Authors: Ahmed Ouammi

Abstract:

This paper presents an integrated decision framework to support decision makers in the selection and optimal allocation of wind power plants in the electric grid. The developed approach intends to maximize the benefice related to the project investment during the planning period. The proposed decision model considers the main cost components, meteorological data, environmental impacts, operation and regulation constraints, and territorial information. The decision framework is expressed as a stochastic constrained optimization problem with the aim to identify the suitable locations and related optimal wind turbine technology considering the operational constraints and maximizing the benefice. The developed decision support system is applied to a case study to demonstrate and validate its performance.

Keywords: decision support systems, electric power grid, optimization, wind energy

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Authors: N. Rajendra Prasad

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Resveratrol (RSV), a grape phytochemical, has drawn greater attention because of its beneficial ef-fects against cancer. However, RSV has some draw-backs such as unstabilization, poor water solubility and short biological half time, which limit the utili-zation of RSV in medicine, food and pharmaceutical industries. In this study, we have encapsulated RSV in gelatin nanoparticles (GNPs) and studied its anti-cancer efficacy in NCI-H460 lung cancer cells. SEM and DLS studies have revealed that the prepared RSV-GNPs possess spherical shape with a mean diameter of 294 nm. The successful encapsulation of RSV in GNPs has been achieved by the cross-linker glutaraldehyde probably through Schiff base reaction and hydrogen bond interaction. Spectrophotometric analysis revealed that the max-imum of 93.6% of RSV has been entrapped in GNPs. In vitro drug release kinetics indicated that there was an initial burst release followed by a slow and sustained release of RSV from GNPs. The prepared RSV-GNPs exhibited very rapid and more efficient cellular uptake than free RSV. Further, RSV-GNPs treatment showed greater antiproliferative efficacy than free RSV treatment in NCI-H460 cells. It has been found that greater ROS generation, DNA damage and apoptotic incidence in RSV-GNPs treated cells than free RSV treatment. Erythrocyte aggregation assay showed that the prepared RSV-GNPs formulation elicit no toxic response. HPLC analysis revealed that RSV-GNPs was more bioavailable and had a longer half-life than free RSV. Hence, GNPs carrier system might be a promising mode for controlled delivery and for improved therapeutic index of poorly water soluble RSV.

Keywords: resveratrol, coacervation, anticancer gelatin nanoparticles, lung cancer, controlled release

Procedia PDF Downloads 450

Authors: Tatiana L. Avalos-Rendon, Elias A. Pasten Chelala, Carlos J. Mendoza EScobedo, Ignacio A. Figueroa, Victor H. Lara, Luis M. Palacios-Romero

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The cement industry is facing cost increments in energy supply, requirements for reduction of CO₂, and insufficient supply of raw materials of good quality. According to all these environmental issues, cement industry must change its consumption patterns and reduce CO₂ emissions to the atmosphere. This can be achieved by generating environmental consciousness, which encourages the use of industrial by-products and/or recycling for the production of cement, as well as alternate, environment-friendly methods of synthesis which reduce CO₂. Calcination is the conventional method for the obtainment of Portland cement clinker. This method consists of grinding and mixing of raw materials (limestone, clay, etc.) in an adequate dosage. Resulting mix has a clinkerization temperature of 1450 °C so that the formation of the main component occur: alite (Ca₃SiO₅, C₃S). Considering that the energy required to produce C₃S is 1810 kJ kg -1, calcination method for the obtainment of clinker represents two major disadvantages: long thermal treatment and elevated temperatures of synthesis, both of which cause high emissions of carbon dioxide (CO₂) to the atmosphere. Belite Portland clinker is characterized by having a low content of calcium oxide (CaO), causing the presence of alite to diminish and favoring the formation of belite (β-Ca₂SiO₄, C₂S), so production of clinker requires a reduced energy consumption (1350 kJ kg-1), releasing less CO₂ to the atmosphere. Conventionally, β-Ca₂SiO₄ is synthetized by the calcination of calcium carbonate (CaCO₃) and silicon dioxide (SiO₂) through the reaction in solid state at temperatures greater than 1300 °C. Resulting belite shows low hydraulic reactivity. Therefore, this study concerns a new simple modified combustion method for the synthesis of two belite cements at low temperatures (1000 °C). Silica fume, as subproduct of metallurgic industry and commercial natural zeolite were utilized as raw materials. These are considered low-cost materials and were utilized with no additional purification process. Belite cements properties were characterized by XRD, SEM, EDS and BET techniques. Hydration capacity of belite cements was calculated while the mechanical strength was determined in ordinary Portland cement specimens (PC) with a 10% partial replacement of the belite cements obtained. Results showed belite cements presented relatively high surface áreas, at early ages mechanical strengths similar to those of alite cement and comparable to strengths of belite cements obtained by different synthesis methods. Cements obtained in this work present good hydraulic reactivity properties.

Keywords: belite, silica fume, zeolite, hydraulic reactivity

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Authors: S. Merazga, F. Boudeffar, A. Bouaoua, A. Cheriet, M. Berouaken, M. Mebarki, K. Ayouz, N. Gabouze

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Several anode materials as transition metal oxides (Fe3O4, SnO2 a, SnO2, LiCoO2, and Li₄Ti₅O₁₂) has been used. Although titanium oxide has attracted great attention as a; superior electrode for Li-ion batteries due tohis excellent characteristic such as: high capacity, low cost and non-toxicity. In this work, the Synthesis and Characterization of Si Doped Li₄Ti₅O₁₂ with hydrothermal Method was electrochemically evaluated. The SEM images shows that the morphology of LTO powders sizes in the range 70nm.The electrochemical properties of synthesizer nanopowders are investigated for use as an anode active material for lithium-ion batteries by galvanostatic techniques in Li-half cells, obtaining reversible discharge capacity of 173.8 mAh/g at 0.1C even upon 100 cycles.Though the doped powders exhibit an upgrade in The electrical conductivity , This is suitable for use as a high-power cathode material for lithium-ion batteries.

Keywords: LTO, li-ion, battteries, anode

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Authors: Abazar Ghorbani, W. M. Wishwajith W. Kandegama, Seyed Mehdi Razavi, Moxian Chen

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The roles of hydrogen sulfide (H₂S) and melatonin (MT) as gasotransmitters in plants are widely recognised. Nevertheless, the precise nature of their involvement in defensive reactions remains uncertain. This study investigates the impact of the ML-H2S interaction on tomato plants exposed to vanadium (V) toxicity, focusing on synthesising secondary metabolites and V metal sequestration. The treatments applied in this study included a control (T1), V stress (T2), MT+V (T3), MT+H2S+V (T4), MT+hypotaurine (HT)+V (T5), and MT+H2S+HT+V (T6). These treatments were administered: MT (150 µM) as a foliar spray pre-treatment (3X), HT treatment (0.1 mM, an H2S scavenger) as root immersion for 12 hours as pre-treatments, and H2S (NaHS, 0.2 mM) and V (40 mg/L) treatments added to the Hoagland solution for 2 weeks. Results demonstrate that ML and H2S+ML treatments alleviate V toxicity by promoting the transcription of key genes (ANS, F3H, CHS, DFR, PAL, and CHI) involved in phenolic and anthocyanin biosynthesis. Moreover, they decreased V uptake and accumulation and enhanced the transcription of genes involved in glutathione and phytochelatin synthesis (GSH1, PCS, and ABC1), leading to V sequestration in roots and protection against V-induced damage. Additionally, ML and H2S+ML treatments optimize chlorophyll metabolism, and increase internal H2S levels, thereby promoting tomato growth under V stress. The combined treatment of ML+H2S shows superior effects compared to ML alone, suggesting synergistic/interactive effects between these two substances. Furthermore, inhibition of the beneficial impact of ML+H2S and ML treatments by HT, an H2S scavenger, underscores the significant involvement of H₂S in the signaling pathway activated by ML during V toxicity. Overall, these findings suggest that ML requires the presence of endogenous H₂S to mitigate V-induced adverse effects on tomato seedlings.

Keywords: vanadium toxicity, secondary metabolites, vanadium sequestration, h2s-melatonin crosstalk

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Authors: Takashi Ueda, Shinichi Enoki

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Forging parts is used to automobiles. Because they have high strength and it is possible to press them into complicated shape. When it is possible to manufacture hollow forging parts, it leads to reduce weight of the automobiles. But, hollow forging parts are confined to axisymmetrical shape. Hollow forging parts that were pressed to complicated shape are expected. Therefore, we forge a blank that aluminum alloy was inserted in stainless steel. After that, we can provide complex forging parts that are reduced weight, if it is possible to be melted the aluminum alloy away by using different of melting points. It is necessary to establish heat forging analysis method on blank consist of stainless steel and aluminum alloy. Because, this forging is different from conventional forging and this technology is not confirmed. In this study, we compared forging experiment with numerical analysis on the view point of forming load and shape after forming and establish how to set the material temperatures of two metals and material property of stainless steel on the analysis method. Consequently, temperature difference of stainless steel and aluminum alloy was obtained by experiment. We got material property of stainless steel on forging experimental by compression tests. We had compared numerical analysis that was used the temperature difference of two metals and the material property of stainless steel on forging experimental with forging experiment. Forging analysis method on blank consist of two metals was established by result of numerical analysis having agreed with result of forging experiment.

Keywords: forging, lightweight, analysis, hollow

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Authors: Mncedisi Trinity Dewa, Andre Francois Van Der Merwe, Stephen Matope

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Tool, Die and Mould-making (TDM) firms have been known to play a pivotal role in the growth and development of the manufacturing sectors in most economies. Their output contributes significantly to the quality, cost and delivery speed of final manufactured parts. Unfortunately, the South African Tool, Die and Mould-making manufacturers have not been competing on the local or global market in a significant way. This reality has hampered the productivity and growth of the sector thus attracting intervention. The paper explores the shortcomings South African toolmakers have to overcome to restore their competitive position globally. Results from a global benchmarking survey on the tooling sector are used to establish a roadmap of what South African toolmakers can do to become a productive, World Class force on the global market.

Keywords: competitive performance objectives, toolmakers, world-class manufacturing, lead times

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Authors: Guanghua Lu, Zhenhua Yan

Abstract:

To investigate the estrogenic contamination and potential risk of Taihu Lake, eight active biomonitoring points in the northern section of Taihu Lake were set up and located in Wangyuhe River outlet (P1), Gonghu Bay (P2 and P3), Meiliang Bay (P4 and P5), Zhushan Bay (P6 and P7) and Lake Centre (P8). A suite of biomarkers in caged fish after in situ exposure for 28 days, coupled with six selected exogenous estrogens in water, were determined in May and December 2011. Six target estrogens, namely estrone (E1), 17b-estradiol (E2), ethinylestradiol (EE2), estriol (E3), diethylstilbestrol (DES) and bisphenol A (BPA), were quantified using UPLC/MS/MS. The concentrations of E1, E2, E3, EE2, DES and BPA ranged from ND to 3.61 ng/L, ND to 17.3 ng/L, ND to 1.65 ng/L, ND to 10.2 ng/L, ND to 34.6 ng/L, and 3.95 to 207 ng/L, respectively. BPA was detected at all sampling points at all test periods, E2 was detected at 95% of samples, E1 and EE2 was detected at 75% of samples, and E3 was detected only in December 2011 with quite low concentrations. Each individual estrogen concentration measured at each sampling point was multiplied by its relative potency to gain the estradiol equivalent (EEQ). The total EEQ values in all the monitoring points ranged from 5.69 to 17.8 ng/L in May 2011, and from 4.46 to 21.1 ng/L in December 2011. E2 and EE2 were thought to be the major causal agents responsible for the estrogenic activities. Serum vitellogenin and E2 levels, gonadal DNA damage, and gonadosomatic index were measured in the in situ exposed fish. An enhanced integrated biomarker response (EIBR) was calculated and used to evaluate potential feminization risk of fish in the polluted area of Taihu Lake. EIBR index showed good agreement with the observed total EEQ levels in water. Our results indicated that Gong bay and the lake center had a low estrogenic risk, whereas Wangyuhe River, Meiliang Bay, and Zhushan Bay might present a higher risk to fish.

Keywords: active biomonitoring, estrogen, feminization risk, Taihu Lake

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Authors: A. Goma Amira, U. E. Mahrous

Abstract:

Measuring the effect of perinatal lead exposure on learning ability of offspring is considered as a sensitive and selective index for providing an early marker for central nervous system damage produced by this toxic metal. A total of 35 Sprague-Dawley adult rats were used to investigate the effect of lead acetate toxicity on behavioral patterns of adult female rats and learning ability of offspring. Rats were allotted into 4 groups, group one received 1g/l lead acetate (n=10), group two received 1.5g/l lead acetate (n=10), group three received 2g/l lead acetate in drinking water (n=10), and control group did not receive lead acetate (n=5) from 8th day of pregnancy till weaning of pups. The obtained results revealed a dose-dependent increase in the feeding time, drinking frequency, licking frequency, scratching frequency, licking litters, nest building, and retrieving frequencies, while standing time increased significantly in rats treated with 1.5g/l lead acetate than other treated groups and control. On the contrary, lying time decreased gradually in a dose-dependent manner. Moreover, movement activities were higher in rats treated with 1g/l lead acetate than other treated groups and control. Furthermore, time spent in closed arms was significantly lower in rats given 2g/l lead acetate than other treated groups, while they spent significantly much time spent in open arms than other treated groups which could be attributed to occurrence of adaptation. Furthermore, number of entries in open arms was-dose dependent. However, the ratio between open/closed arms revealed a significant decrease in rats treated with 2g/l lead acetate than the control group.

Keywords: lead toxicity, rats, learning ability, behavior

Procedia PDF Downloads 382

Authors: Asma Poursoroush

Abstract:

Solid-supported lipid bilayers are often used as a simple model for studies of biological membranes. The presence of a solid substrate that interacts attractively with lipid head-groups is expected to affect the phase behavior of the supported bilayer. Molecular dynamics simulations of a coarse-grained model are thus performed to investigate the phase behavior of supported one-component lipid bilayer membranes. Our results show that the attraction of the lipid head groups to the substrate leads to a phase behavior that is different from that of a free standing lipid bilayer. In particular, we found that the phase behaviors of the two leaflets are decoupled in the presence of a substrate. The proximal leaflet undergoes a clear gel-to-fluid phase transition at a temperature lower than that of a free standing bilayer, and that decreases with increasing strength of the substrate-lipid attraction. The distal leaflet, however, undergoes a change from a homogeneous liquid phase at high temperatures to a heterogeneous state consisting of small liquid and gel domains, with the average size of the gel domains that increases with decreasing temperature. While the chain order parameter of the proximal leaflet clearly shows a gel-fluid phase transition, the chain order parameter of the distal leaflet does not exhibit a clear phase transition. The decoupling in the phase behavior of the two leaflets is due to a non-symmteric lipid distribution in the two leaflets resulting from the presence of the substrate.

Keywords: membrane, substrate, molecular dynamics, simulation

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Authors: U. V. Okpala

Abstract:

Flood is an overflow of water that submerges or ‘drowns’ land. In developing countries it occurs as a result of blocking of natural and man-made drainages and poor maintenance of water dams/reservoirs which seldom give way after persistent heavy down pours. In coastal lowlands and swamp lands, flooding is aided mainly by blocked channels and indiscriminate sand fling of coastal swamp areas and natural drainage channel for urban development/constructions. In this paper, the causes of flood and possible scientific, technological, political, economic and social impacts of flood disaster on the environment a case study of Anambra State have been studied. Often times flooding is caused by climate change, especially in the developed economy where scientific mitigating options are highly employed. Researchers have identified Green Houses Gases (GHG) as the cause of global climate change. The recent flood disaster in Anambra State which caused physical damage to structures, social dislocation, contamination of clean drinking water, spread of water-borne diseases, shortage of crops and food supplies, death of non-tolerant tree species, disruption in transportation system, serious economic loss and psychological trauma is a function of climate change. There is need to encourage generation of renewable energy sources, use of less carbon intensive fuels and other energy efficient sources. Carbon capture/sequestration, proper management of our drainage systems and good maintenance of our dams are good option towards saving the environment.

Keywords: flooding, climate change, carbon capture, energy systems

Procedia PDF Downloads 382

Authors: Low Khee Wai

Abstract:

Lossing of opportunity by Malaysian Oil and Gas Services Equipment (OGSE) companies can be a major issue in developing and sustain Malaysia’s own Oil & Gas Industry. Despite the rapid growth of Oil & Gas industry in Malaysia for the past 40 years, Malaysia still not developing sufficient OGSE companies in order to support its own Oil & Gas Industry. In examining the scenario, this study aims to identify the factors causing the under-developing of OGSE companies in Malaysia. Conceptual Review method were used to analyse the factors that cause the under-development of Malaysia OGSE. The 4 factors identified were Time, Cost, Human Resource and Stakeholder Management. This survey explained the phenomena and the challenge of the industry and translated into the factors that cause the under-developing of OGSE companies in Malaysia. Finally, it should bring awareness to the government, authorities, and stakeholder in order to improve the ecology of Oil & Gas Industry in Malaysia.

Keywords: oil & gas in Malaysia, Malaysia local oil & gas services equipment (OGSE), oil & gas project management, project performance

Procedia PDF Downloads 137

Authors: Gregory Michael McMahon

Abstract:

Risk management for the purposes of minimizing the damages from the operations of dams has met with opposition emerging from organisations and authorities, and their practitioners. It appears that the cause may be a misunderstanding of risk management arising from exchanges that mix deterministic thinking with risk-centric thinking and that do not separate uncertainty from reliability and accuracy from probability. This paper sets out those misunderstandings that arose from dam operations at Wivenhoe in 2011, using a comparison of outcomes that have been based on the methodology and its rules and those that have been operated by applying misunderstandings of the rules. The paper addresses the performance of one risk-centric Flood Manual for Wivenhoe Dam in achieving a risk management outcome. A mixture of engineering, administrative, and legal factors appear to have combined to reduce the outcomes from the risk approach. These are described. The findings are that a risk-centric Manual may need to assist administrations in the conduct of scenario training regimes, in responding to healthy audit reporting, and in the development of decision-support systems. The principal assistance needed from the Manual, however, is to assist engineering and the law to a good understanding of how risks are managed – do not assume that risk management is understood. The wider findings are that the critical profession for decision-making downstream of the meteorologist is not dam engineering or hydrology, or hydraulics; it is risk management. Risk management will provide the minimum flood damage outcome where actual rainfalls match or exceed forecasts of rainfalls, that therefore risk management will provide the best approach for the likely history of flooding in the life of a dam, and provisions made for worst cases may be state of the art in risk management. The principal conclusion is the need for training in both risk management as a discipline and also in the application of risk management rules to particular dam operational scenarios.

Keywords: risk management, flood control, dam operations, deterministic thinking

Procedia PDF Downloads 97