Search results for: change in velocity
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8445

Search results for: change in velocity

6105 Change Detection of Water Bodies in Dhaka City: An Analysis Using Geographic Information System and Remote Sensing

Authors: M. Humayun Kabir, Mahamuda Afroze, K. Maudood Elahi

Abstract:

Since the late 1900s, unplanned and rapid urbanization processes have drastically altered the land, reduced water bodies, and decreased vegetation cover in the capital city of Bangladesh, Dhaka. The capitalist modes of urbanization results in the encroachment of the surface water bodies in this city. The main goal of this study is to investigate the change detection of water bodies in Dhaka city, analyzing spatial distribution of water bodies and calculating the changing rate of it. This effort aims to influence public policy for environmental justice initiatives around protecting water bodies for ensuring proper function of the urban ecosystem. This study accomplishes research goal by compiling satellite imageries into GIS software to understand the changes of water bodies in Dhaka city. The work focuses on the late 20th century to early 21st century to analyze this city before and after major infrastructural changes occurred in unplanned manner. The land use of the study area has been classified into four categories, and the areas of the different land use have been calculated using MS Excel and SPSS. The results reveal that the urbanization expanded from central to northern part and major encroachment occurred at the western and eastern part of the city. It has also been found that, in 1988, the total area of water bodies was 8935.38 hectares, and it gradually decreased, and in 1998, 2008, 2017, the total areas of water bodies reached 6065.73, 4853.32, 2077.56 hectares, respectively. Rapid population growth, unplanned urbanization, and industrialization have generated pressure to change the land use pattern in Dhaka city. These expansion processes are engulfing wetland, water bodies, and vegetation cover without considering environmental impact. In order to regain the wetland and surface water bodies, the concern authorities must implement laws and act as a legal instrument in this regard and take action against the violators of it. This research is the synthesis of time series data that provides a complete picture of the water body’s status of Dhaka city that might help to make plans and policies for water body conservation.

Keywords: ecosystem, GIS, industrialization, land use, remote sensing, urbanization

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6104 Pastoralist Transhumance and Conflict along the Nigeria-niger Borderlands: Towards New Perspective for Effective Border Management in Africa

Authors: Abubakar Samaila

Abstract:

Pastoralism has been an old practice in the Sahel region of west Africa. In recent years, pastoralists in Nigeria have increasingly been migrating on seasonal transhumance southward from the neighboring countries, especially Niger Republic, in search of better grazing conditions due to mainly, climate change. This has increased pressure on farm lands which instigate farmer-herder conflicts. These conflicts occur mainly between farmers and pastoralists but also between pastoralist groups themselves. However, there has been a shift in these conflicts recently to involve traditional institutions and, in some cases, the local authorities along the borderlands. The involvement of local institutions in the conflict has created an incentive to local actors, particularly pastoralcommunity-based groups, in responding to these violent threats. As pastoralists are mobile, these conflicts became difficult to contain and, thus, spill across borders. Consequently, the conflict has now transformed into an urbanized regional conflicts that involve some major cities along the Nigeria-Niger borderlands; Sokoto, Zamfara, and Katsina on the Nigerian side andDosso, Tahoa andMaradi in Niger republic. These areas are now experiencing unprecedented growing wave of violence that have become complex and escalates into a hydra-social conflict. The aim of this research is to investigate how the fluidities of Nigeria-Niger borderland intensified armed conflicts between the local pastoral organizations and sedentary populationspreading to some urban cities along the borderlands. The paper further suggests alternative approaches towards addressing the perennial crisis in African borderlands.

Keywords: pastoralism, climate change, conflict, nigeria, niger, borderlands

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6103 The Role of Natural Gas in Reducing Carbon Emissions

Authors: Abdulrahman Nami Almutairi

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In the face of escalating climate change concerns, the concept of smart cities emerges as a promising approach to mitigate carbon emissions and move towards carbon neutrality. This paper provides a comprehensive review of the role of Natural Gas in achieving carbon neutrality. Natural gas has often been seen as a transitional fuel in the context of reducing carbon emissions. Its main role stems from being cleaner than coal and oil when burned for electricity generation and industrial processes. The urgent need to address this global issue has prompted a global shift towards cleaner energy sources and sustainable practices. In this endeavor, natural gas has emerged as a pivotal player, hailed for its potential to mitigate carbon emissions, and facilitate the transition to a low-carbon economy. With its lower carbon intensity compared to conventional fossil fuels, natural gas presents itself as a promising alternative for meeting energy demands while reducing environmental impact. As the world stands at a critical juncture in the fight against climate change, exploring the potential of natural gas as a transitional fuel offers insights into pathways towards a more sustainable and resilient future. By critically evaluating its opportunities and challenges, we can harness the potential of natural gas as a transitional fuel while advancing towards a cleaner, more resilient energy system. Through collaborative efforts and informed decision-making, we can pave the way for a future where energy is not only abundant but also environmentally sustainable and socially equitable.

Keywords: natural gas, clean fuel, carbon emissions, global warming, environmental protection

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6102 Fracture Pressure Predict Based on Well Logs of Depleted Reservoir in Southern Iraqi Oilfield

Authors: Raed H. Allawi

Abstract:

Formation pressure is the most critical parameter in hydrocarbon exploration and exploitation. Specifically, predicting abnormal pressures (high formation pressures) and subnormal pressure zones can provide valuable information to minimize uncertainty for anticipated drilling challenges and risks. This study aims to interpret and delineate the pore and fracture pressure of the Mishrif reservoir in the southern Iraq Oilfield. The data required to implement this study included acoustic compression wave, gamma-ray, bulk density, and drilling events. Furthermore, supporting these models needs the pore pressure measurement from the Modular Formation Dynamics Tester (MDT). Many measured values of pore pressure were used to validate the accurate model. Using sonic velocity approaches, the mean absolute percentage error (MAPE) was about 4%. The fracture pressure results were consistent with the measurement data, actual drilling report, and events. The model's results will be a guide for successful drilling in future wells in the same oilfield.

Keywords: pore pressure, fracture pressure, overburden pressure, effective stress, drilling events

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6101 Seismic History and Liquefaction Resistance: A Comparative Study of Sites in California

Authors: Tarek Abdoun, Waleed Elsekelly

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Introduction: Liquefaction of soils during earthquakes can have significant consequences on the stability of structures and infrastructure. This study focuses on comparing two liquefaction case histories in California, namely the response of the Wildlife site in the Imperial Valley to the 2010 El-Mayor Cucapah earthquake (Mw = 7.2, amax = 0.15g) and the response of the Treasure Island Fire Station (F.S.) site in the San Francisco Bay area to the 1989 Loma Prieta Earthquake (Mw = 6.9, amax = 0.16g). Both case histories involve liquefiable layers of silty sand with non-plastic fines, similar shear wave velocities, low CPT cone penetration resistances, and groundwater tables at similar depths. The liquefaction charts based on shear wave velocity field predict liquefaction at both sites. However, a significant difference arises in their pore pressure responses during the earthquakes. The Wildlife site did not experience liquefaction, as evidenced by piezometer data, while the Treasure Island F.S. site did liquefy during the shaking. Objective: The primary objective of this study is to investigate and understand the reason for the contrasting pore pressure responses observed at the Wildlife site and the Treasure Island F.S. site despite their similar geological characteristics and predicted liquefaction potential. By conducting a detailed analysis of similarities and differences between the two case histories, the objective is to identify the factors that contributed to the higher liquefaction resistance exhibited by the Wildlife site. Methodology: To achieve this objective, the geological and seismic data available for both sites were gathered and analyzed. Then their soil profiles, seismic characteristics, and liquefaction potential as predicted by shear wave velocity-based liquefaction charts were analyzed. Furthermore, the seismic histories of both regions were examined. The number of previous earthquakes capable of generating significant excess pore pressures for each critical layer was assessed. This analysis involved estimating the total seismic activity that the Wildlife and Treasure Island F.S. critical layers experienced over time. In addition to historical data, centrifuge and large-scale experiments were conducted to explore the impact of prior seismic activity on liquefaction resistance. These findings served as supporting evidence for the investigation. Conclusions: The higher liquefaction resistance observed at the Wildlife site and other sites in the Imperial Valley can be attributed to preshaking by previous earthquakes. The Wildlife critical layer was subjected to a substantially greater number of seismic events capable of generating significant excess pore pressures over time compared to the Treasure Island F.S. layer. This crucial disparity arises from the difference in seismic activity between the two regions in the past century. In conclusion, this research sheds light on the complex interplay between geological characteristics, seismic history, and liquefaction behavior. It emphasizes the significant impact of past seismic activity on liquefaction resistance and can provide valuable insights for evaluating the stability of sandy sites in other seismic regions.

Keywords: liquefaction, case histories, centrifuge, preshaking

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6100 Simulation to Detect Virtual Fractional Flow Reserve in Coronary Artery Idealized Models

Authors: Nabila Jaman, K. E. Hoque, S. Sawall, M. Ferdows

Abstract:

Coronary artery disease (CAD) is one of the most lethal diseases of the cardiovascular diseases. Coronary arteries stenosis and bifurcation angles closely interact for myocardial infarction. We want to use computer-aided design model coupled with computational hemodynamics (CHD) simulation for detecting several types of coronary artery stenosis with different locations in an idealized model for identifying virtual fractional flow reserve (vFFR). The vFFR provides us the information about the severity of stenosis in the computational models. Another goal is that we want to imitate patient-specific computed tomography coronary artery angiography model for constructing our idealized models with different left anterior descending (LAD) and left circumflex (LCx) bifurcation angles. Further, we want to analyze whether the bifurcation angles has an impact on the creation of narrowness in coronary arteries or not. The numerical simulation provides the CHD parameters such as wall shear stress (WSS), velocity magnitude and pressure gradient (PGD) that allow us the information of stenosis condition in the computational domain.

Keywords: CAD, CHD, vFFR, bifurcation angles, coronary stenosis

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6099 Influence of Different Sports on the Taste Perception and Acceptability of a Commercial Sports Drink among University Student-Athletes

Authors: Jana Daher, Ammar Olabi, Elie-Jacques Fares, Samer Kharrroubi, Tarek Gherbal

Abstract:

It has been previously suggested that the perception and acceptability of fluids significantly varies between exercise and non-exercise situations. The study investigates the influence of different types of sports on the taste perception and acceptability of a commercial sports drink. A sample of Gatorade – red orange flavor was evaluated pre and post exercise by 34 male university athletes (20 weightlifters, 14 runners) recruited from the American University of Beirut. Urine samples were collected from the participants to test for hydration. Sensory testing examined the change in the intensity of sweetness, saltiness, sourness, and the thirst-quenching ability of the drink as well as its acceptability with respect to the type of sport practiced. Results indicated that the acceptability of the drink increased as the hydration status of the athletes decreased (p<0.01). No significant change was found in the perception of the sensory attributes between exercise and non-exercise conditions. However, there were significant differences between the two sports groups in the ratings of the thirst-quenching ability of the drink where runners’ ratings increased after exercise while weightlifters’ ratings decreased after exercise (p<0.01). These findings suggest that exercise has a larger effect on the acceptability and overall liking of the beverage compared to other sensory attributes. An enhanced liking of the beverage is key for optimal replenishment of lost fluids and electrolytes after exercise.

Keywords: hedonic, liking, sweetness, thirst-quenching

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6098 Simulation Research of Innovative Ignition System of ASz62IR Radial Aircraft Engine

Authors: Miroslaw Wendeker, Piotr Kacejko, Mariusz Duk, Pawel Karpinski

Abstract:

The research in the field of aircraft internal combustion engines is currently driven by the needs of decreasing fuel consumption and CO2 emissions, while fulfilling the level of safety. Currently, reciprocating aircraft engines are found in sports, emergency, agricultural and recreation aviation. Technically, they are most at a pre-war knowledge of the theory of operation, design and manufacturing technology, especially if compared to that high level of development of automotive engines. Typically, these engines are driven by carburetors of a quite primitive construction. At present, due to environmental requirements and dealing with a climate change, it is beneficial to develop aircraft piston engines and adopt the achievements of automotive engineering such as computer-controlled low-pressure injection, electronic ignition control and biofuels. The paper describes simulation research of the innovative power and control systems for the aircraft radial engine of high power. Installing an electronic ignition system in the radial aircraft engine is a fundamental innovative idea of this solution. Consequently, the required level of safety and better functionality as compared to the today’s plug system can be guaranteed. In this framework, this research work focuses on describing a methodology for optimizing the electronically controlled ignition system. This attempt can reduce emissions of toxic compounds as a result of lowered fuel consumption, optimized combustion and engine capability of efficient combustion of ecological fuels. New, redundant elements of the control system can improve the safety of aircraft. Consequently, the required level of safety and better functionality as compared to the today’s plug system can be guaranteed. The simulation research aimed to determine the vulnerability of the values measured (they were planned as the quantities measured by the measurement systems) to determining the optimal ignition angle (the angle of maximum torque at a given operating point). The described results covered: a) research in steady states; b) velocity ranging from 1500 to 2200 rpm (every 100 rpm); c) loading ranging from propeller power to maximum power; d) altitude ranging according to the International Standard Atmosphere from 0 to 8000 m (every 1000 m); e) fuel: automotive gasoline ES95. The three models of different types of ignition coil (different energy discharge) were studied. The analysis aimed at the optimization of the design of the innovative ignition system for an aircraft engine. The optimization involved: a) the optimization of the measurement systems; b) the optimization of actuator systems. The studies enabled the research on the vulnerability of the signals to the control of the ignition timing. Accordingly, the number and type of sensors were determined for the ignition system to achieve its optimal performance. The results confirmed the limited benefits, in terms of fuel consumption. Thus, including spark management in the optimization is mandatory to significantly decrease the fuel consumption. This work has been financed by the Polish National Centre for Research and Development, INNOLOT, under Grant Agreement No. INNOLOT/I/1/NCBR/2013.

Keywords: piston engine, radial engine, ignition system, CFD model, engine optimization

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6097 Assessment of Acute Cardiovascular Responses to Moderate and Vigorous Intensity Aerobic Exercises in Sedentary Adults and Amateur Athletes

Authors: Caner Yilmaz, Zuhal Didem Takinaci

Abstract:

Introduction: Today, our knowledge about the effects of physical activity performed at the different intensity of the cardiovascular system are still not clear. Therefore, to contribute to the literature, in our study, sedentary individuals and amateur athletes were assessed in a single session with the aim of evaluating the cardiovascular effects of the moderate and severe exercise. Methods: 80 participants (40 amateur athletes and 40 sedentary, young adults) participated in our study. Participants were divided into two groups: amateur athletes (mean age: 25.0 ± 3.6 yrs) and sedentary in group II (mean age: 23.8 ± 3.7 yrs). Participants in both groups were assessed twice, namely, firstly, at moderate intensity (5km/h 30 min. walking) and secondly at the vigorous intensity (8km/h 20 min. jogging). Participants’ SBP (Systolic Blood Pressure), DBP (Diastolic Blood Pressure), HR (Heart Rate), SpO₂ (Oxygen Saturation), BT (Body Temperature) and RR (Respiratory Rate) were measured. Results: In our study, the findings showed that after moderate-intensity aerobic exercise, change in SBP, DBP, and SpO₂ were significantly higher in Group II (p < 0.05). After the severe intensity aerobic exercises, change in SBP, SpO₂, HR, and RR was significantly higher in Group II (p < 0.05). The BORG score of Group II was significantly higher after both moderate and severe intensity aerobic exercise (p < 0.05). Conclusion: The cardiovascular responses of amateur athletes were closer to initial values, and the differences between the two groups were increased in direct proportion to the intensity of the exercise. Both exercise intensities could be adequate.

Keywords: aerobic, exercise, sedantary, cardi̇ovascular

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6096 Laser-Ultrasonic Method for Measuring the Local Elastic Moduli of Porosity Isotropic Composite Materials

Authors: Alexander A. Karabutov, Natalia B. Podymova, Elena B. Cherepetskaya, Vladimir A. Makarov, Yulia G. Sokolovskaya

Abstract:

The laser-ultrasonic method is realized for quantifying the influence of porosity on the local Young’s modulus of isotropic composite materials. The method is based on a laser generation of ultrasound pulses combined with measurement of the phase velocity of longitudinal and shear acoustic waves in samples. The main advantage of this method compared with traditional ultrasonic research methods is the efficient generation of short and powerful probing acoustic pulses required for reliable testing of ultrasound absorbing and scattering heterogeneous materials. Using as an example samples of a metal matrix composite with reinforcing microparticles of silicon carbide in various concentrations, it is shown that to provide an effective increase in Young’s modulus with increasing concentration of microparticles, the porosity of the final sample should not exceed 2%.

Keywords: laser ultrasonic, longitudinal and shear ultrasonic waves, porosity, composite, local elastic moduli

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6095 A Discrete Element Method-Based Simulation of Toppling Failure Considering Block Interaction

Authors: Hooman Dabirmanesh, Attila M. Zsaki

Abstract:

The toppling failure mode in a rock mass is considerably different from the most common sliding failure type along an existing or an induced slip plane. Block toppling is observed in a rock mass which consists of both a widely-spaced basal cross-joint set and a closely-spaced discontinuity set dipping into the slope. For this case, failure occurs when the structure cannot bear the tensile portion of bending stress, and the columns or blocks overturn by their own weight. This paper presents a particle-based discrete element model of rock blocks subjected to a toppling failure where geometric conditions and interaction among blocks are investigated. A series of parametric studies have been conducted on particles’ size, arrangement and bond contact among of particles which are made the blocks. Firstly, a numerical investigation on a one-block system was verified. Afterward, a slope consisting of multi-blocks was developed to study toppling failure and interaction forces between blocks. The results show that the formation of blocks, especially between the block and basal plane surface, can change the process of failure. The results also demonstrate that the initial configuration of particles used to form the blocks has a significant role in achieving accurate simulation results. The size of particles and bond contacts have a considerable influence to change the progress of toppling failure.

Keywords: block toppling failure, contact interaction, discrete element, particle size, random generation

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6094 Urban Heat Island Intensity Assessment through Comparative Study on Land Surface Temperature and Normalized Difference Vegetation Index: A Case Study of Chittagong, Bangladesh

Authors: Tausif A. Ishtiaque, Zarrin T. Tasin, Kazi S. Akter

Abstract:

Current trend of urban expansion, especially in the developing countries has caused significant changes in land cover, which is generating great concern due to its widespread environmental degradation. Energy consumption of the cities is also increasing with the aggravated heat island effect. Distribution of land surface temperature (LST) is one of the most significant climatic parameters affected by urban land cover change. Recent increasing trend of LST is causing elevated temperature profile of the built up area with less vegetative cover. Gradual change in land cover, especially decrease in vegetative cover is enhancing the Urban Heat Island (UHI) effect in the developing cities around the world. Increase in the amount of urban vegetation cover can be a useful solution for the reduction of UHI intensity. LST and Normalized Difference Vegetation Index (NDVI) have widely been accepted as reliable indicators of UHI and vegetation abundance respectively. Chittagong, the second largest city of Bangladesh, has been a growth center due to rapid urbanization over the last several decades. This study assesses the intensity of UHI in Chittagong city by analyzing the relationship between LST and NDVI based on the type of land use/land cover (LULC) in the study area applying an integrated approach of Geographic Information System (GIS), remote sensing (RS), and regression analysis. Land cover map is prepared through an interactive supervised classification using remotely sensed data from Landsat ETM+ image along with NDVI differencing using ArcGIS. LST and NDVI values are extracted from the same image. The regression analysis between LST and NDVI indicates that within the study area, UHI is directly correlated with LST while negatively correlated with NDVI. It interprets that surface temperature reduces with increase in vegetation cover along with reduction in UHI intensity. Moreover, there are noticeable differences in the relationship between LST and NDVI based on the type of LULC. In other words, depending on the type of land usage, increase in vegetation cover has a varying impact on the UHI intensity. This analysis will contribute to the formulation of sustainable urban land use planning decisions as well as suggesting suitable actions for mitigation of UHI intensity within the study area.

Keywords: land cover change, land surface temperature, normalized difference vegetation index, urban heat island

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6093 Characteristics of Old-Growth and Secondary Forests in Relation to Age and Typhoon Disturbance

Authors: Teng-Chiu Lin, Pei-Jen Lee Shaner, Shin-Yu Lin

Abstract:

Both forest age and physical damages due to weather events such as tropical cyclones can influence forest characteristics and subsequently its capacity to sequester carbon. Detangling these influences is therefore a pressing issue under climate change. In this study, we compared the compositional and structural characteristics of three forests in Taiwan differing in age and severity of typhoon disturbances. We found that the two forests (one old-growth forest and one secondary forest) experiencing more severe typhoon disturbances had shorter stature, higher wood density, higher tree species diversity, and lower typhoon-induced tree mortality than the other secondary forest experiencing less severe typhoon disturbances. On the other hand, the old-growth forest had a larger amount of woody debris than the two secondary forests, suggesting a dominant role of forest age on woody debris accumulation. Of the three forests, only the two experiencing more severe typhoon disturbances formed new gaps following two 2015 typhoons, and between these two forests, the secondary forest gained more gaps than the old-growth forest. Consider that older forests generally have more gaps due to a higher background tree mortality, our findings suggest that the age effects on gap dynamics may be reversed by typhoon disturbances. This study demonstrated the effects of typhoons on forest characteristics, some of which could negate the age effects and rejuvenate older forests. If cyclone disturbances were to intensity under climate change, the capacity of older forests to sequester carbon may be reduced.

Keywords: typhoon, canpy gap, coarse woody debris, forest stature, forest age

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6092 Numerical Simulation of Von Karman Swirling Bioconvection Nanofluid Flow from a Deformable Rotating Disk

Authors: Ali Kadir, S. R. Mishra, M. Shamshuddin, O. Anwar Beg

Abstract:

Motivation- Rotating disk bio-reactors are fundamental to numerous medical/biochemical engineering processes including oxygen transfer, chromatography, purification and swirl-assisted pumping. The modern upsurge in biologically-enhanced engineering devices has embraced new phenomena including bioconvection of micro-organisms (photo-tactic, oxy-tactic, gyrotactic etc). The proven thermal performance superiority of nanofluids i.e. base fluids doped with engineered nanoparticles has also stimulated immense implementation in biomedical designs. Motivated by these emerging applications, we present a numerical thermofluid dynamic simulation of the transport phenomena in bioconvection nanofluid rotating disk bioreactor flow. Methodology- We study analytically and computationally the time-dependent three-dimensional viscous gyrotactic bioconvection in swirling nanofluid flow from a rotating disk configuration. The disk is also deformable i.e. able to extend (stretch) in the radial direction. Stefan blowing is included. The Buongiorno dilute nanofluid model is adopted wherein Brownian motion and thermophoresis are the dominant nanoscale effects. The primitive conservation equations for mass, radial, tangential and axial momentum, heat (energy), nanoparticle concentration and micro-organism density function are formulated in a cylindrical polar coordinate system with appropriate wall and free stream boundary conditions. A mass convective condition is also incorporated at the disk surface. Forced convection is considered i.e. buoyancy forces are neglected. This highly nonlinear, strongly coupled system of unsteady partial differential equations is normalized with the classical Von Karman and other transformations to render the boundary value problem (BVP) into an ordinary differential system which is solved with the efficient Adomian decomposition method (ADM). Validation with earlier Runge-Kutta shooting computations in the literature is also conducted. Extensive computations are presented (with the aid of MATLAB symbolic software) for radial and circumferential velocity components, temperature, nanoparticle concentration, micro-organism density number and gradients of these functions at the disk surface (radial local skin friction, local circumferential skin friction, Local Nusselt number, Local Sherwood number, motile microorganism mass transfer rate). Main Findings- Increasing radial stretching parameter decreases radial velocity and radial skin friction, reduces azimuthal velocity and skin friction, decreases local Nusselt number and motile micro-organism mass wall flux whereas it increases nano-particle local Sherwood number. Disk deceleration accelerates the radial flow, damps the azimuthal flow, decreases temperatures and thermal boundary layer thickness, depletes the nano-particle concentration magnitudes (and associated nano-particle species boundary layer thickness) and furthermore decreases the micro-organism density number and gyrotactic micro-organism species boundary layer thickness. Increasing Stefan blowing accelerates the radial flow and azimuthal (circumferential flow), elevates temperatures of the nanofluid, boosts nano-particle concentration (volume fraction) and gyrotactic micro-organism density number magnitudes whereas suction generates the reverse effects. Increasing suction effect reduces radial skin friction and azimuthal skin friction, local Nusselt number, and motile micro-organism wall mass flux whereas it enhances the nano-particle species local Sherwood number. Conclusions - Important transport characteristics are identified of relevance to real bioreactor nanotechnological systems not discussed in previous works. ADM is shown to achieve very rapid convergence and highly accurate solutions and shows excellent promise in simulating swirling multi-physical nano-bioconvection fluid dynamics problems. Furthermore, it provides an excellent complement to more general commercial computational fluid dynamics simulations.

Keywords: bio-nanofluids, rotating disk bioreactors, Von Karman swirling flow, numerical solutions

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6091 Geo-spatial Analysis: The Impact of Drought and Productivity to the Poverty in East Java, Indonesia

Authors: Yessi Rahmawati, Andiga Kusuma Nur Ichsan, Fitria Nur Anggraeni

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Climate change is one of the focus studies that many researchers focus on in the present world, either in the emerging countries or developed countries which is one of the main pillars on Sustainable Development Goals (SDGs). There is on-going discussion that climate change can affect natural disaster, namely drought, storm, flood, and many others; and also the impact on human life. East Java is the best performances and has economic potential that should be utilized. Despite the economic performance and high agriculture productivity, East Java has the highest number of people under the poverty line. The present study is to measuring the contribution of drought and productivity of agriculture to the poverty in East Java, Indonesia, using spatial econometrics analysis. The authors collect data from 2008 – 2015 from Indonesia’s Ministry of Agriculture, Natural Disaster Management Agency (BNPB), and Official Statistic (BPS). First, the result shows the existence of spatial autocorrelation between drought and poverty. Second, the present research confirms that there is strong relationship between drought and poverty. the majority of farmer in East Java are still relies on the rainfall and traditional irrigation system. When the drought strikes, mostly the farmer will lose their income; make them become more vulnerable household, and trap them into poverty line. The present research will give empirical studies regarding drought and poverty in the academics world.

Keywords: SDGs, drought, poverty, Indonesia, spatial econometrics, spatial autocorrelation

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6090 The Impact of Leadership Style and Managers Decision Making on Organizational Resulting in Ship Manufacturing Company

Authors: ZeinolAbedin Rahmani, Marzieh Evazi Borazjani, Nooshin Salehi

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Organizations are increasingly facing changes and developments scientific, technological, social, cultural changes among these organizations those ones are reckoned successful and effective that in addition to coordinating the development of modern society can forecast future changes and be able to accommodate these changes in order to create favorable developments to build a better future. But we can change that with the changes that occur in the organization of the program it will distinguish. Today's organizations need leaders that change and grow them have to survive. In fact, without transformational managers and leaders, it is certainly difficult to create changes in organizations. Both private and public organizations need to increase knowledge and awareness of the cause widespread changes in the structure, culture and practice for the viability and sustainability of life and growth and development. By now, different signs have determined different causes for a suitable function of employees. However, the important thing is that the commitment of the employees to their organization has always been very important. Since the decrease of organization commitment causes the high rate of absenteeism, turnover intentions, and even to reduce the impact of health staff. and these factors prevent organizations from achieving its goals. If organizations want to retain staff, the organization must find a way to be happy and continue their work with commitment, motivation, and willingness. So here is the need for strong leaders, analysts, creative and transformational upper ranks more than ever is felt. The aim of this study is to revise history, the leadership style of managers shipbuilding company by using the MLQ model.

Keywords: leadership style, managers, organizational, manufacturing company, sustainability of life

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6089 Effect of the Initial Billet Shape Parameters on the Final Product in a Backward Extrusion Process for Pressure Vessels

Authors: Archana Thangavelu, Han-Ik Park, Young-Chul Park, Joon-Hong Park

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In this numerical study, we have proposed a method for evaluation of backward extrusion process of pressure vessel made up of steel. Demand for lighter and stiffer products have been increasing in the last years especially in automobile engineering. Through detailed finite element analysis, effective stress, strain and velocity profile have been obtained with optimal range. The process design of a forward and backward extrusion axe-symmetric part has been studied. Forging is mainly carried out because forged products are highly reliable and possess superior mechanical properties when compared to normal products. Performing computational simulations of 3D hot forging with various dimensions of billet and optimization of weight is carried out using Taguchi Orthogonal Array (OA) Optimization technique. The technique used in this study can be used for newly developed materials to investigate its forgeability for much complicated shapes in closed hot die forging process.

Keywords: backward extrusion, hot forging, optimization, finite element analysis, Taguchi method

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6088 Finite Element Simulation for Preliminary Study on Microorganism Detection System

Authors: Muhammad Rosli Abdullah, Noor Hasmiza Harun

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A microorganism detection system has a potential to be used with the advancement in a biosensor development. The detection system requires an optical sensing system, microfluidic device and biological reagent. Although, the biosensors are available in the market, a label free and a lab-on-chip approach will promote a flexible solution. As a preliminary study of microorganism detection, three mechanisms such as Total Internal Reflection (TIR), Micro Fluidic Channel (MFC) and magnetic-electric field propagation were study and simulated. The objective are to identify the TIR angle, MFC parabolic flow and the wavelength for the microorganism detection. The simulation result indicates that evanescent wave is achieved when TIR angle > 42°, the corner and centre of a parabolic velocity are 0.02 m/s and 0.06 m/s respectively, and a higher energy distribution of a perfect electromagnetic scattering with dipole resonance radiation occurs at 500 nm. This simulation is beneficial to determine the components of the microorganism detection system that does not rely on classical microbiological, immunological and genetic methods which are laborious, time-consuming procedures and confined to specialized laboratories with expensive instrumentation equipment.

Keywords: microorganism, microfluidic, total internal reflection, lab on chip

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6087 Translational and Rotational Effect of Earthquake Ground Motion on a Bridge Substructure

Authors: Tauhidur Rahman, Gitartha Kalita

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In this study a four span box girder bridge is considered and effect of the rotational and translational earthquake ground motion have been thoroughly investigated. This study is motivated by the fact that in many countries the translational and rotational components of earthquake ground motion, especially rocking, is not adequately considered in analysing the overall response of the structures subjected to earthquake ground excitations. Much consideration is given to only the horizontal components of the earthquake ground motion during the response analysis of structures. In the present research work, P waves, SV waves and Rayleigh wave excitations are considered for different angle of incidence. In the present paper, the four span bridge is model considering the effects of vertical and rocking components of P, SV and Rayleigh wave excitations. Ground responses namely displacement, velocity and acceleration of the substructures of the bridge have been considered for rotational and translational effects in addition to the horizontal ground motion due to earthquake and wind.

Keywords: ground motion, response, rotational effects, translational effects

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6086 Effects of Fermentation Techniques on the Quality of Cocoa Beans

Authors: Monday O. Ale, Adebukola A. Akintade, Olasunbo O. Orungbemi

Abstract:

Fermentation as an important operation in the processing of cocoa beans is now affected by the recent climate change across the globe. The major requirement for effective fermentation is the ability of the material used to retain sufficient heat for the required microbial activities. Apart from the effects of climate on the rate of heat retention, the materials used for fermentation plays an important role. Most Farmers still restrict fermentation activities to the use of traditional methods. Improving on cocoa fermentation in this era of climate change makes it necessary to work on other materials that can be suitable for cocoa fermentation. Therefore, the objective of this study was to determine the effects of fermentation techniques on the quality of cocoa beans. The materials used in this fermentation research were heap-leaves (traditional), stainless steel, plastic tin, plastic basket and wooden box. The period of fermentation varies from zero days to 10 days. Physical and chemical tests were carried out for variables in quality determination in the samples. The weight per bean varied from 1.0-1.2 g after drying across the samples and the major color of the dry beans observed was brown except with the samples from stainless steel. The moisture content varied from 5.5-7%. The mineral content and the heavy metals decreased with increase in the fermentation period. A wooden box can conclusively be used as an alternative to heap-leaves as there was no significant difference in the physical features of the samples fermented with the two methods. The use of a wooden box as an alternative for cocoa fermentation is therefore recommended for cocoa farmers.

Keywords: fermentation, effects, fermentation materials, period, quality

Procedia PDF Downloads 207
6085 High School Stem Curriculum and Example of Laboratory Work That Shows How Microcomputers Can Help in Understanding of Physical Concepts

Authors: Jelena Slugan, Ivica Ružić

Abstract:

We are witnessing the rapid development of technologies that change the world around us. However, curriculums and teaching processes are often slow to adapt to the change; it takes time, money and expertise to implement technology in the classroom. Therefore, the University of Split, Croatia, partnered with local school Marko Marulić High School and created the project "Modern competence in modern high schools" as part of which five different curriculums for STEM areas were developed. One of the curriculums involves combining information technology with physics. The main idea was to teach students how to use different circuits and microcomputers to explore nature and physical phenomena. As a result, using electrical circuits, students are able to recreate in the classroom the phenomena that they observe every day in their environment. So far, high school students had very little opportunity to perform experiments independently, and especially, those physics experiment did not involve ICT. Therefore, this project has a great importance, because the students will finally get a chance to develop themselves in accordance to modern technologies. This paper presents some new methods of teaching physics that will help students to develop experimental skills through the study of deterministic nature of physical laws. Students will learn how to formulate hypotheses, model physical problems using the electronic circuits and evaluate their results. While doing that, they will also acquire useful problem solving skills.

Keywords: ICT in physics, curriculum, laboratory activities, STEM (science, technology, engineering, mathematics)

Procedia PDF Downloads 201
6084 Improving Human Resources Management in Indian Civil Service

Authors: Anant Deogaonkar, Archana Nanoty

Abstract:

The term civil service plays a vital role in functioning of any government. In today’s modern era of globalization civil services essentially contribute for the success of the good governance system. The civil service in India refers to the body of government officials employed in civil occupations that are neither political nor judicial. The Indian Civil Services were created to foster the idea of unity in diversity with the expectation of giving continuity and change in administration independent of the political scenario and turmoil affecting the country. The civil service is an integral part of administration and the structures of administration to determine the way civil service functions. The concept of good governance necessarily precludes the effective human resource management ensuring the root level reach of the good governance. The serious matter of concern is the element of change. The civil service in general has maintained status quo instead of sweeping changes in social and economic scenario. One may disagree for this but it is a fact on the street that the Indian civil service was not able to deliver up to the expectations of the people and was lacking on the service front. The effective management of human resources at civil service needs to be prioritized and will form a key factor in successful delivery of the desired results may be in minimum duration. This paper focuses on the various ways of effective management of human resources in civil services. It also highlights the importance of improvement in human resource management in civil services with the detailed discussion of positives and negatives if any of the human resource management in civil services.

Keywords: civil services, human resources management, India, governance

Procedia PDF Downloads 318
6083 Numerical Analysis of Supersonic Impinging Jets onto Resonance Tube

Authors: Shinji Sato, M. M. A. Alam, Manabu Takao

Abstract:

In recent, investigation of an unsteady flow inside the resonance tube have become a strongly motivated research field for their potential application as high-frequency actuators. By generating a shock wave inside the resonance tube, a high temperature and pressure can be achieved inside the tube, and this high temperature can also be used to ignite a jet engine. In the present research, a computational fluid dynamics (CFD) analysis was carried out to investigate the flow inside the resonance tube. The density-based solver of rhoCentralFoam in OpenFOAM was used to numerically simulate the flow. The supersonic jet that was driven by a cylindrical nozzle with a nominal exit diameter of φd = 20.3 mm impinged onto the resonance tube. The jet pressure ratio was varied between 2.6 and 7.8. The gap s between the nozzle exit and tube entrance was changed between 1.5d and 3.0d. The diameter and length of the tube were taken as D = 1.25d and L=3.0D, respectively. As a result, when a supersonic jet has impinged onto the resonance tube, a compression wave was found generating inside the tube and propagating towards the tube end wall. This wave train resulted in a rise in the end wall gas temperature and pressure. While, in an outflow phase, the gas near tube enwall was found cooling back isentropically to its initial temperature. Thus, the compression waves repeated a reciprocating motion in the tube like a piston, and a fluctuation in the end wall pressures and temperatures were observed. A significant change was found in the end wall pressures and temperatures with a change of jet flow conditions. In this study, the highest temperature was confirmed at a jet pressure ratio of 4.2 and a gap of s=2.0d

Keywords: compressible flow, OpenFOAM, oscillations, a resonance tube, shockwave

Procedia PDF Downloads 149
6082 Wind Velocity Mitigation for Conceptual Design: A Spatial Decision (Support Framework)

Authors: Mohamed Khallaf, Hossein M Rizeei

Abstract:

Simulating wind pattern behavior over proposed urban features is critical in the early stage of the conceptual design of both architectural and urban disciplines. However, it is typically not possible for designers to explore the impact of wind flow profiles across new urban developments due to a lack of real data and inaccurate estimation of building parameters. Modeling the details of existing and proposed urban features and testing them against wind flows is the missing part of the conceptual design puzzle where architectural and urban discipline can focus. This research aims to develop a spatial decision-support design method utilizing LiDAR, GIS, and performance-based wind simulation technology to mitigate wind-related hazards on a design by simulating alternative design scenarios at the pedestrian level prior to its implementation in Sydney, Australia. The result of the experiment demonstrates the capability of the proposed framework to improve pedestrian comfort in relation to wind profile.

Keywords: spatial decision-support design, performance-based wind simulation, LiDAR, GIS

Procedia PDF Downloads 124
6081 Effects of Concentrator and Encapsulated Phase Change Material for Desalination: An Experimental Study

Authors: Arunkumar Thirugnanasambantham, Velraj Ramalingam

Abstract:

An experimental attempt has been made to study the effect of system integration by two different concentrator assisted desalting systems. The compound parabolic concentrator (CPC) and compound conical concentrator (CCC) are used in this research work. Two solar desalination systems, the single slope solar still (SSSS) and pyramid solar still (PSS), have been integrated with a CCC and compound parabolic concentrator-concentric circular tubular solar still (CPC-CCTSS). To study the effect of system integration, a thick cloth prevents the entry of sunlight into the solar still top. Additionally, the concentrator assisted desalting systems are equipped with phase change material (PCM) for enhancement. In CCC-SSSS, PCM has been filled inside copper balls and placed on the SSSS basin. The PCM is loaded in the specially designed circular trough of the tubular solar still. Here, the used concentrators and distillers are not the same. Two methodologies are followed here to produce the fresh water even while the distillers are blocked from the sunlight. They are (1) thermosyphon effect in CCC-SSSS and (2) waste heat recovery from CPC-CCTSS. The results showed that the productivity of CCC-SSSS, CCC-SSSS with PCM and CCC-SSSS (PCM) top cover shaded were found as 2680 ml / m² / day, 3240 ml / m² / day, and 1646 ml / m² / day. Similarly, the productivity of the CPC-CCTSS-PSS, CPC-CCTSS (PCM)-PSS and CPC-CCTSS (PCM)-PSS top cover shaded were found as 7160 ml / m² / day, 7346 ml / m² / day, and ml / m² / day. The productivity of the CCC-SSSS and CPC-CCTSS-PSS is examined, and conclusions are drawn such as the solar radiation blocked distillers productivity did not drop to zero.

Keywords: compound conical concentrator, compound parabolic concentrator, desalination, system integration

Procedia PDF Downloads 261
6080 Magnetohydrodynamics (MHD) Boundary Layer Flow Past A Stretching Plate with Heat Transfer and Viscous Dissipation

Authors: Jiya Mohammed, Tsadu Shuaib, Yusuf Abdulhakeem

Abstract:

The research work focuses on the cases of MHD boundary layer flow past a stretching plate with heat transfer and viscous dissipation. The non-linear of momentum and energy equation are transform into ordinary differential equation by using similarity transformation, the resulting equation are solved using Adomian Decomposition Method (ADM). An attempt has been made to show the potentials and wide range application of the Adomian decomposition method in the comparison with the previous one in solving heat transfer problems. The Pade approximates value (η= 11[11, 11]) is use on the difficulty at infinity. The results are compared by numerical technique method. A vivid conclusion can be drawn from the results that ADM provides highly precise numerical solution for non-linear differential equations. The result where accurate especially for η ≤ 4, a general equating terms of Eckert number (Ec), Prandtl number (Pr) and magnetic parameter ( ) is derived which was used to investigate velocity and temperature profiles in boundary layer.

Keywords: MHD, Adomian decomposition, boundary layer, viscous dissipation

Procedia PDF Downloads 551
6079 Influence of a Pulsatile Electroosmotic Flow on the Dispersivity of a Non-Reactive Solute through a Microcapillary

Authors: Jaime Muñoz, José Arcos, Oscar Bautista Federico Méndez

Abstract:

The influence of a pulsatile electroosmotic flow (PEOF) at the rate of spread, or dispersivity, for a non-reactive solute released in a microcapillary with slippage at the boundary wall (modeled by the Navier-slip condition) is theoretically analyzed. Based on the flow velocity field developed under such conditions, the present study implements an analytical scheme of scaling known as the Theory of Homogenization, in order to obtain a mathematical expression for the dispersivity, valid at a large time scale where the initial transients have vanished and the solute spreads under the Taylor dispersion influence. Our results show the dispersivity is a function of a slip coefficient, the amplitude of the imposed electric field, the Debye length and the angular Reynolds number, highlighting the importance of the latter as an enhancement/detrimental factor on the dispersivity, which allows to promote the PEOF as a strong candidate for chemical species separation at lab-on-a-chip devices.

Keywords: dispersivity, microcapillary, Navier-slip condition, pulsatile electroosmotic flow, Taylor dispersion, Theory of Homogenization

Procedia PDF Downloads 215
6078 The Feasibility of Using Milled Glass Wastes in Concrete to Resist Freezing-Thawing Action

Authors: Raed Abendeh, Mousa Bani Baker, Zaydoun Abu Salem, Hesham Ahmad

Abstract:

The using of waste materials in the construction industry can reduce the dependence on the natural aggregates which are going at the end to deplete. The glass waste is generated in a huge amount which can make one of its disposal in concrete industry effective not only as a green solution but also as an advantage to enhance the performance of mechanical properties and durability of concrete. This article reports the performance of concrete specimens containing different percentages of milled glass waste as a partial replacement of cement (Powder), when they are subject to cycles of freezing and thawing. The tests were conducted on 75-mm cubes and 75 x 75 x 300-mm prisms. Compressive strength based on laboratory testing and non-destructive ultrasonic pulse velocity test were performed during the action of freezing-thawing cycles (F/T). The results revealed that the incorporation of glass waste in concrete mixtures is not only feasible but also showed generally better strength and durability performance than control concrete mixture. It may be said that the recycling of waste glass in concrete mixes is not only a disposal way, but also it can be an exploitation in concrete industry.

Keywords: durability, glass waste, freeze-thaw cycles, non-destructive test

Procedia PDF Downloads 376
6077 Synoptic Analysis of a Heavy Flood in the Province of Sistan-Va-Balouchestan: Iran January 2020

Authors: N. Pegahfar, P. Ghafarian

Abstract:

In this research, the synoptic weather conditions during the heavy flood of 10-12 January 2020 in the Sistan-va-Balouchestan Province of Iran will be analyzed. To this aim, reanalysis data from the National Centers for Environmental Prediction (NCEP) and National Center for Atmospheric Research (NCAR), NCEP Global Forecasting System (GFS) analysis data, measured data from a surface station together with satellite images from the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT) have been used from 9 to 12 January 2020. Atmospheric parameters both at the lower troposphere and also at the upper part of that have been used, including absolute vorticity, wind velocity, temperature, geopotential height, relative humidity, and precipitation. Results indicated that both lower-level and upper-level currents were strong. In addition, the transport of a large amount of humidity from the Oman Sea and the Red Sea to the south and southeast of Iran (Sistan-va-Balouchestan Province) led to the vast and unexpected precipitation and then a heavy flood.

Keywords: Sistan-va-Balouchestn Province, heavy flood, synoptic, analysis data

Procedia PDF Downloads 102
6076 Performance of Slot-Entry Hybrid Worn Journal Bearing under Turbulent Lubrication

Authors: Nathi Ram, Saurabh K. Yadav

Abstract:

In turbomachinery, the turbulent flow occurs due to the use of high velocity of low kinematic viscosity lubricants and used in many industrial applications. In the present work, the performance of symmetric slot-entry hybrid worn journal bearing under laminar and turbulent lubrication has been investigated. For turbulent lubrication, the Reynolds equation has been modified using Constantinescu turbulent model. This modified equation has been solved using the finite element method. The effect of turbulent lubrication on bearing’s performance has been presented for symmetric hybrid journal bearing. The slot-entry hybrid worn journal bearing under turbulent/laminar regimes have been investigated. It has been observed that the stiffness and damping coefficients are more for the bearing having slot width ratio (SWR) of 0.25 than the bearing with SWR of 0.5 and 0.75 under the turbulent regime. Further, it is also observed that for constant wear depth parameter, stability threshold speed gets increased for bearing operates at slot width ratio 0.25 under turbulent lubrication.

Keywords: hydrostatic bearings, journal bearings, restrictors, turbulent flow models, finite element technique

Procedia PDF Downloads 164