Search results for: counter flow
2212 Tourism Economics and Tourism Development in Greece, in the Period of the Economic Adjustment Programmes
Authors: Aimilia Vlami
Abstract:
This paper examines the tourist economic development of Greece on the basis of the analysis of the main characteristics of the financing and development processes and the spatial and temporal structure of supply and demand. Taking into consideration the evolution of the economic planning and the policy for the tourist development of Greece over time, we study at the same time: the composition, the changes and the dynamics of the hotel industry in the last 20 years and especially the period of the economic adjustment programmes, where tourism has become a key pillar of development. It is clearly evident that this paper is written in a specific economic situation, which directs as much the emphases as the flow of arguments around the central question of balance of interventions in the tourist space, between the need for planning and practice of policy for sustainable tourist growth and in the de facto adaptation of fragmentary and urgent interventions of shaping and transforming the tourist space, as they are shaped by the requirements of various institutions and interest groups.Keywords: development, Greece, hospitality, economic policy, tourism investments
Procedia PDF Downloads 1322211 Velocity Distribution in Density Currents Flowing over Rough Beds
Authors: Reza Nasrollahpour, Mohamad Hidayat Bin Jamal, Zulhilmi Bin Ismail
Abstract:
Density currents are generated when the fluid of one density is released into another fluid with a different density. These currents occur in a variety of natural and man-made environments, and this emphasises the importance of studying them. In most practical cases, the density currents flow over the surfaces which are not plane; however, there have been limited investigations in this regard. This study uses laboratory experiments to analyse the influence of bottom roughness on the velocity distribution within these dense underflows. The currents are analysed over a plane surface and three different configurations of beam-roughened beds. The velocity profiles are collected using Acoustic Doppler Velocimetry technique, and the distribution of velocity within these currents is formulated for the tested beds. The results indicate that the empirical power and Gaussian relations can describe the velocity distribution in the inner and outer regions of the profiles, respectively. Moreover, it is found that the bottom roughness is the primary controlling parameter in the inner region.Keywords: density currents, velocity profiles, Acoustic Doppler Velocimeter, bed roughness
Procedia PDF Downloads 1852210 The Modality of Multivariate Skew Normal Mixture
Authors: Bader Alruwaili, Surajit Ray
Abstract:
Finite mixtures are a flexible and powerful tool that can be used for univariate and multivariate distributions, and a wide range of research analysis has been conducted based on the multivariate normal mixture and multivariate of a t-mixture. Determining the number of modes is an important activity that, in turn, allows one to determine the number of homogeneous groups in a population. Our work currently being carried out relates to the study of the modality of the skew normal distribution in the univariate and multivariate cases. For the skew normal distribution, the aims are associated with studying the modality of the skew normal distribution and providing the ridgeline, the ridgeline elevation function, the $\Pi$ function, and the curvature function, and this will be conducive to an exploration of the number and location of mode when mixing the two components of skew normal distribution. The subsequent objective is to apply these results to the application of real world data sets, such as flow cytometry data.Keywords: mode, modality, multivariate skew normal, finite mixture, number of mode
Procedia PDF Downloads 4882209 Hydraulic Characteristics of the Tidal River Dongcheon in Busan City
Authors: Young Man Cho, Sang Hyun Kim
Abstract:
Even though various management practices such as sediment dredging were attempted to improve water quality of Dongcheon located in Busan, the environmental condition of this stream was deteriorated. Therefore, Busan metropolitan city had pumped and diverted sea water to upstream of Dongcheon for several years. This study explored hydraulic characteristics of Dongcheon to configure the best management practice for ecological restoration and water quality improvement of a man-made urban stream. Intensive field investigation indicates that average flow velocities at depths of 20% and 80% from the water surface ranged 5 to 10 cm/s and 2 to 5 cm/s, respectively. Concentrations of dissolved oxygen for all depths were less than 0.25 mg/l during low tidal period. Even though density difference can be found along stream depth, density current seems rarely generated in Dongcheon. Short period of high tidal portion and shallow depths are responsible for well-mixing nature of Doncheon.Keywords: hydraulic, tidal river, density current, sea water
Procedia PDF Downloads 2252208 Science and Monitoring Underpinning River Restoration: A Case Study
Authors: Geoffrey Gilfillan, Peter Barham, Lisa Smallwood, David Harper
Abstract:
The ‘Welland for People and Wildlife’ project aimed to improve the River Welland’s ecology and water quality, and to make it more accessible to the community of Market Harborough. A joint monitoring project by the Welland Rivers Trust & University of Leicester was incorporated into the design. The techniques that have been used to measure its success are hydrological, geomorphological, and water quality monitoring, species and habitat surveys, and community engagement. Early results show improvements to flow and habitat diversity, water quality and biodiversity of the river environment. Barrier removal has increased stickleback mating activity, and decreased parasitically infected fish in sample catches. The habitats provided by the berms now boast over 25 native plant species, and the river is clearer, cleaner and with better-oxygenated water.Keywords: community engagement, ecological monitoring, river restoration, water quality
Procedia PDF Downloads 2322207 Collapse Surface Definition of Clayey Sands
Authors: Omid Naeemifar, Ibrahim Naeimifar, Roza Rahbari
Abstract:
It has been shown that a certain collapse surface may be defined for loose sands in the three dimensional space in which the sample sand experiences collapse and instability leading to an unsteady and strain-softening behaviour. The unsteady state due to collapse surface may lead to such phenomena in the sand as liquefaction and flow behaviour during undrained loading. Investigating the existence of the collapse surface in Firoozkooh 161 sand and its different clay mixtures with various plasticities, the present study aims to carry out an in-depth investigation of the effects of clay percent and its plasticity on the clayey sand behaviours. The results obtained indicate that collapse surface characteristics largely depend on fine percent and its plasticity. Interesting findings are also reported in this paper on the effects of fine sand percent and its plasticity on the behavioural characteristics and liquefaction potential of clayey sands.Keywords: critical state, collapse surface, liquefaction, clayey sand
Procedia PDF Downloads 2982206 Price Control: A Comprehensive Step to Control Corruption in the Society
Authors: Muhammad Zia Ullah Baig, Atiq Uz Zama
Abstract:
The motivation of the project is to facilitate the governance body, as well as the common man in his/her daily life consuming product rates, to easily monitor the expense, to control the budget with the help of single SMS (message), e-mail facility, and to manage governance body by task management system. The system will also be capable of finding irregularities being done by the concerned department in mitigating the complaints generated by the customer and also provide a solution to overcome problems. We are building a system that easily controls the price control system of any country, we will feeling proud to give this system free of cost to Indian Government also. The system is able to easily manage and control the price control department of government all over the country. Price control department run in different cities under City District Government, so the system easily run in different cities with different SMS Code and decentralize Database ensure the non-functional requirement of system (scalability, reliability, availability, security, safety). The customer request for the government official price list with respect to his/her city SMS code (price list of all city available on website or application), the server will forward the price list through a SMS, if the product is not available according to the price list the customer generate a complaint through an SMS or using website/smartphone application, complaint is registered in complaint database and forward to inspection department when the complaint is entertained, the inspection department will forward a message about the complaint to customer. Inspection department physically checks the seller who does not follow the price list, but the major issue of the system is corruption, may be inspection officer will take a bribe and resolve the complaint (complaint is fake) in that case the customer will not use the system. The major issue of the system is to distinguish the fake and real complain and fight for corruption in the department. To counter the corruption, our strategy is to rank the complain if the same type of complaint is generated the complaint is in high rank and the higher authority will also notify about that complain, now the higher authority of department have reviewed the complaint and its history, the officer who resolve that complaint in past and the action against the complaint, these data will help in decision-making process, if the complaint was resolved because the officer takes bribe, the higher authority will take action against that officer. When the price of any good is decided the market/former representative is also there, with the mutual understanding of both party the price is decided, the system facilitate the decision-making process. The system shows the price history of any goods, inflation rate, available supply, demand, and the gap between supply and demand, these data will help to allot for the decision-making process.Keywords: price control, goods, government, inspection, department, customer, employees
Procedia PDF Downloads 4122205 Impact of Wheel-Housing on Aerodynamic Drag and Effect on Energy Consumption on an Bus
Authors: Amitabh Das, Yash Jain, Mohammad Rafiq B. Agrewale, K. C. Vora
Abstract:
Role of wheel and underbody aerodynamics of vehicle in the formation of drag forces is detrimental to the fuel (energy) consumption during the course of operation at high velocities. This paper deals with the CFD simulation of the flow around the wheels of a bus with different wheel housing geometry and pattern. Based on benchmarking a model of a bus is selected and analysis is performed. The aerodynamic drag coefficient is obtained and turbulence around wheels is observed using ANSYS Fluent CFD simulation for different combinations of wheel-housing at the front wheels, at the rear wheels and both in the front and rear wheels. The drag force is recorded and corresponding influence on energy consumption on an electric bus is evaluated mathematically. A comparison is drawn between energy consumption of bus body without wheel housing and bus body with wheel housing. The result shows a significant reduction in drag coefficient and fuel consumption.Keywords: wheel-housing, CFD simulation, drag coefficient, energy consumption
Procedia PDF Downloads 1852204 Introducing the Accounting Reform of Public Finance in the Czech Republic
Authors: M. Otrusinova, E. Pastuszkova
Abstract:
The article is addressing the currently ongoing reform processes of transforming the public finance accounting based on cash flow principle to accrual principle. The presented analysis concerns the issues associated with the introduction of the state accounting from the perspective of municipal employees in compiling the opinions of financial experts in conditions of the Czech Republic. The aim of this paper is to present outcomes of analysis focused on currently discussed topics which are related to introducing the accrual principle into accounting of selected entities, especially municipalities and municipality-funded institutions. The output of the paper consists of comparing the application of the accrual principle in the financial reporting of municipalities in the Czech Republic and Slovakia. In conclusion and based on the survey, respondents from Slovak municipalities that have already adopted the accrual accounting principle show better opinion than Czech municipalities.Keywords: accrual principle, accounting, accounting reform, Czech Republic, municipalities, public finance
Procedia PDF Downloads 2622203 Heat Transfer Augmentation in Solar Air Heater Using Fins and Twisted Tape Inserts
Authors: Rajesh Kumar, Prabha Chand
Abstract:
Fins and twisted tape inserts are widely used passive elements to enhance heat transfer rate in various engineering applications. The present paper describes the theoretical analysis of solar air heater fitted with fins and twisted tape inserts. Mathematical model is develop for this novel design of solar air heater and a MATLAB code is generated for the solution of the model. The effect of twist ratio, mass flow rate and inlet temperature on the thermal efficiency and exit air temperature has been investigated. The results are compared with the results of plane solar air heater. Results show a substantial enhancement in heat transfer rate, efficiency and exit air temperature.Keywords: solar air heater, thermal efficiency, twisted tape, twist ratio
Procedia PDF Downloads 2562202 A Heuristic Approach for the General Flowshop Scheduling Problem to Minimize the Makespan
Authors: Mohsen Ziaee
Abstract:
Almost all existing researches on the flowshop scheduling problems focus on the permutation schedules and there is insufficient study dedicated to the general flowshop scheduling problems in the literature, since the modeling and solving of the general flowshop scheduling problems are more difficult than the permutation ones, especially for the large-size problem instances. This paper considers the general flowshop scheduling problem with the objective function of the makespan (F//Cmax). We first find the optimal solution of the problem by solving a mixed integer linear programming model. An efficient heuristic method is then presented to solve the problem. An ant colony optimization algorithm is also proposed for the problem. In order to evaluate the performance of the methods, computational experiments are designed and performed. Numerical results show that the heuristic algorithm can result in reasonable solutions with low computational effort and even achieve optimal solutions in some cases.Keywords: scheduling, general flow shop scheduling problem, makespan, heuristic
Procedia PDF Downloads 2072201 Application of Waterflooding to the Kashkari Oil Field in Northern Afghanistan
Authors: Zabihullah Mahdi, Mahdi Nayab, Sadaf Jalal, Navid Seddiqi
Abstract:
Hydrocarbons represent an important natural resource for the rehabilitation and sustainable development of Afghanistan. In this paper, the use of waterflooding is demonstrated for the petroleum reservoirs of the Kashkari oil field in northern Afghanistan. The technique is based on the Buckley–Leverett frontal-displacement theory, which enables computation of the progress of the waterfront in the reservoir. The relative permeabilities of oil and water, the residual oil saturation, and the irreducible water saturation are obtained from a laboratory experiment. The technique is applied to the laboratory plane-reservoir model to investigate the displacement mechanism and is then compared with the theoretical calculation. Lastly, the technique is applied to the Kashkari oil field to predict the feasible amount of oil that could be produced from this reservoir.Keywords: Buckley–Leverett, waterflooding, petroleum reservoir engineering, two-phase flow, immiscible displacement, porous media, relative permeability
Procedia PDF Downloads 2032200 Temporal Estimation of Hydrodynamic Parameter Variability in Constructed Wetlands
Authors: Mohammad Moezzibadi, Isabelle Charpentier, Adrien Wanko, Robert Mosé
Abstract:
The calibration of hydrodynamic parameters for subsurface constructed wetlands (CWs) is a sensitive process since highly non-linear equations are involved in unsaturated flow modeling. CW systems are engineered systems designed to favour natural treatment processes involving wetland vegetation, soil, and their microbial flora. Their significant efficiency at reducing the ecological impact of urban runoff has been recently proved in the field. Numerical flow modeling in a vertical variably saturated CW is here carried out by implementing the Richards model by means of a mixed hybrid finite element method (MHFEM), particularly well adapted to the simulation of heterogeneous media, and the van Genuchten-Mualem parametrization. For validation purposes, MHFEM results were compared to those of HYDRUS (a software based on a finite element discretization). As van Genuchten-Mualem soil hydrodynamic parameters depend on water content, their estimation is subject to considerable experimental and numerical studies. In particular, the sensitivity analysis performed with respect to the van Genuchten-Mualem parameters reveals a predominant influence of the shape parameters α, n and the saturated conductivity of the filter on the piezometric heads, during saturation and desaturation. Modeling issues arise when the soil reaches oven-dry conditions. A particular attention should also be brought to boundary condition modeling (surface ponding or evaporation) to be able to tackle different sequences of rainfall-runoff events. For proper parameter identification, large field datasets would be needed. As these are usually not available, notably due to the randomness of the storm events, we thus propose a simple, robust and low-cost numerical method for the inverse modeling of the soil hydrodynamic properties. Among the methods, the variational data assimilation technique introduced by Le Dimet and Talagrand is applied. To that end, a variational data assimilation technique is implemented by applying automatic differentiation (AD) to augment computer codes with derivative computations. Note that very little effort is needed to obtain the differentiated code using the on-line Tapenade AD engine. Field data are collected for a three-layered CW located in Strasbourg (Alsace, France) at the water edge of the urban water stream Ostwaldergraben, during several months. Identification experiments are conducted by comparing measured and computed piezometric head by means of the least square objective function. The temporal variability of hydrodynamic parameter is then assessed and analyzed.Keywords: automatic differentiation, constructed wetland, inverse method, mixed hybrid FEM, sensitivity analysis
Procedia PDF Downloads 1642199 Human Dental Pulp Stem Cells Attenuate Streptozotocin-Induced Parotid Gland Injury in Rats
Authors: Gehan ElAkabawy
Abstract:
Background: Diabetes mellitus causes severe deteriorations of almost all the organs and systems of the body, as well as significant damage to the oral cavity. The oral changes are mainly related to salivary glands dysfunction characterized by hyposalivation and xerostomia, which significantly reduce diabetic patients’ quality of life. Human dental pulp stem cells represent a promising source for cell-based therapies, owing to their easy, minimally invasive surgical access, and high proliferative capacity. It was reported that the trophic support mediated by dental pulp stem cells can rescue the functional and structural alterations of damaged salivary glands. However, potential differentiation and paracrine effects of human dental pulp stem cells in diabetic-induced parotid gland damage have not been previously investigated. Our study aimed to investigate the therapeutic effects of intravenous transplantation of human dental pulp stem cells (hDPSCs) on parotid gland injury in a rat model of streptozotocin (STZ)-induced type 1 diabetes. Methods: Thirty Sprague-Dawley male rats were randomly categorised into three groups: control, diabetic (STZ), and transplanted (STZ+hDPSCs). hDPSCs or vehicle was injected into the tail vein 7 days after STZ injection. The fasting blood glucose levels were monitored weekly. A glucose tolerance test was performed, and the parotid gland weight, salivary flow rate, oxidative stress indices, parotid gland histology, and caspase-3, vascular endothelial growth factor (VEGF), and proliferating cell nuclear antigen (PCNA) expression in parotid tissues were assessed 28 days post-transplantation. Results: Transplantation of hDPSCs downregulated blood glucose, improved the salivary flow rate, and reduced oxidative stress. The cells migrated to, survived, and differentiated into acinar, ductal, and myoepithelial cells in the STZ-injured parotid gland. Moreover, they downregulated the expression of caspase-3 and upregulated the expression of VEGF and PCNA, likely exerting pro-angiogenetic and antiapoptotic effects and promoting endogenous regeneration. In addition, the transplanted cells enhanced the parotid nitric oxide (NO) -tetrahydrobiopterin (BH4) pathway. Conclusions: Our results show that hDPSCs can migrate to and survive within the STZ-injured parotid gland, where they prevent its functional and morphological damage by restoring normal glucose levels, differentiating into parotid cell populations, and stimulating paracrine-mediated regeneration. Thus, hDPSCs may have therapeutic potential in the treatment of diabetes-induced parotid gland injury.Keywords: dental pulp stem cells, diabetes, streptozotocin, parotid gland
Procedia PDF Downloads 1962198 Axial Flux Permanent Magnet Motor Design and Optimization by Using Artificial Neural Networks
Authors: Tugce Talay, Kadir Erkan
Abstract:
In this study, the necessary steps for the design of axial flow permanent magnet motors are shown. The design and analysis of the engine were carried out based on ANSYS Maxwell program. The design parameters of the ANSYS Maxwell program and the artificial neural network system were established in MATLAB and the most efficient design parameters were found with the trained neural network. The results of the Maxwell program and the results of the artificial neural networks are compared and optimal working design parameters are found. The most efficient design parameters were submitted to the ANSYS Maxwell 3D design and the cogging torque was examined and design studies were carried out to reduce the cogging torque.Keywords: AFPM, ANSYS Maxwell, cogging torque, design optimisation, efficiency, NNTOOL
Procedia PDF Downloads 2202197 Distribution of Synechococcus and Prochlorococcus in Southeastern Coast of Peninsular Malaysia
Authors: Roswati Md. Amin, Nurul Asmera Mudiman, Muhammad Faisal Abd. Rahman, Md-Suffian Idris, Noor Hazwani Mohd Azmi
Abstract:
Distribution of picophytoplankton from two genera, Synechococcus and Prochlorococcus at the surface water (0.5m) were observed from coastal to offshore area of the southeastern coast of Peninsular Malaysia, for a six day cruise in August 2014 during SouthWest monsoon. The picophytoplankton was divided into two different size fractions (0.7-2.7μm and <0.7 μm) by filtering through GF/D (2.7 μm) and GF/F (0.7 μm) filter papers and counted by using flow cytometer. Synechococcus and Prochlorococcus contribute higher at 0.7-2.7μm size range (ca. 90% and 95%, respectively) compared to <0.7 μm (ca. 10% and 5%, respectively). Synechococcus (>52%) dominated the total picophytoplankton compared to Prochlorococcus (<26%) for both size fractions in southeastern coast of Peninsular Malaysia. Total density (<2.7 μm) of Synechococcus was ranging between 1.72 x104 and 12.57 x104 cells ml-1, while Prochlorococcus varied from 1.50 x104 to 8.62 x104. Both Synechococcus and Prochlorococcus abundance showed a decreasing trend from coastal to offshore.Keywords: Peninsular Malaysia, prochlorococcus, South China Sea, synechococcus
Procedia PDF Downloads 3162196 The Twin Terminal of Pedestrian Trajectory Based on City Intelligent Model (CIM) 4.0
Authors: Chen Xi, Liu Xuebing, Lao Xueru, Kuan Sinman, Jiang Yike, Wang Hanwei, Yang Xiaolang, Zhou Junjie, Xie Jinpeng
Abstract:
To further promote the development of smart cities, the microscopic "nerve endings" of the City Intelligent Model (CIM) are extended to be more sensitive. In this paper, we develop a pedestrian trajectory twin terminal based on the CIM and CNN technology. It also uses 5G networks, architectural and geoinformatics technologies, convolutional neural networks, combined with deep learning networks for human behavior recognition models, to provide empirical data such as 'pedestrian flow data and human behavioral characteristics data', and ultimately form spatial performance evaluation criteria and spatial performance warning systems, to make the empirical data accurate and intelligent for prediction and decision making.Keywords: urban planning, urban governance, CIM, artificial intelligence, sustainable development
Procedia PDF Downloads 4192195 Experimental Support for the District Metered Areas/Pressure Management Areas Application
Authors: K. Ilicic, D. Smoljan
Abstract:
The purpose of the paper is to present and verify a methodology of decreasing water losses by introducing and managing District Metered Areas (DMA) and Pressure Management Areas (PMA) by analyzing the results of the application of the methodology to the water supply system of the city of Zagreb. Since it is a relatively large system that has been expanding rapidly, approach to addressing water losses was possible only by splitting the system to smaller flow and pressure zones. Besides, the geographical and technical limitations had imposed the necessity of high pressure in the system that needed to be reduced to the technically optimal level. Results of activities were monitored on a general and local level by establishing, monitoring, and controlling indicators that had been established by the International Water Association (IWA), among which the most recognizable were non-revenue water, water losses and real losses as presented in the paper.Keywords: district metered area, pressure metered area, active leakage control, water losses
Procedia PDF Downloads 1842194 Civilian and Military Responses to Domestic Security Threats: A Cross-Case Analysis of Belgium, France, and the United Kingdom
Authors: John Hardy
Abstract:
The domestic security environment in Europe has changed dramatically in recent years. Since January 2015, a significant number of domestic security threats that emerged in Europe were located in Belgium, France and the United Kingdom. While some threats were detected in the planning phase, many also resulted in terrorist attacks. Authorities in all three countries instituted special or emergency measures to provide additional security to their populations. Each country combined an additional policing presence with a specific military operation to contribute to a comprehensive security response to domestic threats. This study presents a cross-case analysis of three countries’ civilian and military responses to domestic security threats in Europe. Each case study features a unique approach to combining civilian and military capabilities in similar domestic security operations during the same time period and threat environment. The research design focuses on five variables relevant to the relationship between civilian and military roles in each security response. These are the distinction between policing and military roles, the legal framework for the domestic deployment of military forces, prior experience in civil-military coordination, the institutional framework for threat assessments, and the level of public support for the domestic use of military forces. These variables examine the influence of domestic social, political, and legal factors on the design of combined civil-military operations in response to domestic security threats. Each case study focuses on a specific operation: Operation Vigilant Guard in Belgium, Operation Sentinel in France, and Operation Temperer in the United Kingdom. The results demonstrate that the level of distinction between policing and military roles and the existence of a clear and robust legal framework for the domestic use force by military personnel significantly influence the design and implementation of civilian and military roles in domestic security operations. The findings of this study indicate that Belgium, France and the United Kingdom experienced different design and implementation challenges for their domestic security operations. Belgium and France initially had less-developed legal frameworks for deploying the military in domestic security operations than the United Kingdom. This was offset by public support for enacting emergency measures and the strength of existing civil-military coordination mechanisms. The United Kingdom had a well-developed legal framework for integrating civilian and military capabilities in domestic security operations. However, its experiences in Ireland also made the government more sensitive to public perceptions regarding the domestic deployment of military forces.Keywords: counter-terrorism, democracy, homeland security, intelligence, militarization, policing
Procedia PDF Downloads 1422193 Exergy Analysis of Reverse Osmosis for Potable Water and Land Irrigation
Authors: M. Sarai Atab, A. Smallbone, A. P. Roskilly
Abstract:
A thermodynamic study is performed on the Reverse Osmosis (RO) desalination process for brackish water. The detailed RO model of thermodynamics properties with and without an energy recovery device was built in Simulink/MATLAB and validated against reported measurement data. The efficiency of desalination plants can be estimated by both the first and second laws of thermodynamics. While the first law focuses on the quantity of energy, the second law analysis (i.e. exergy analysis) introduces quality. This paper used the Main Outfall Drain in Iraq as a case study to conduct energy and exergy analysis of RO process. The result shows that it is feasible to use energy recovery method for reverse osmosis with salinity less than 15000 ppm as the exergy efficiency increases twice. Moreover, this analysis shows that the highest exergy destruction occurs in the rejected water and lowest occurs in the permeate flow rate accounting 37% for 4.3% respectively.Keywords: brackish water, exergy, irrigation, reverse osmosis (RO)
Procedia PDF Downloads 1742192 The Effects of the Aspect Ratio of a Flexible Cylinder on the Vortex Dynamics
Authors: Abouzar Kaboudian, Ravi Chaithanya Mysa, Boo Cheong Khoo, Rajeev Kumar Jaiman
Abstract:
The vortex structures observed in the wake of a flexible cylinder can be significantly different from those of a traditional vibrating, spring mounted, rigid cylinder. These differences can significantly affect the VIV characteristics of the flow and subsequently the VIV response of the cylindrical structures. In this work, we present how the aspect ratio of a flexible cylinder can change the vortex structures in its wake. We will discuss different vortex dynamics which can be observed in the wake of the vibrating flexible cylinder, and how they can affect the vibrational response of the cylinder. Moreover, we will study the transition of these structures versus the aspect ratio of the flexible cylinder. We will discuss how these transitions affect the in-line and transverse forces on the structure. In the end, we will provide general guidelines on the minimum acceptable aspect ratio for the offshore riser studies which may have grave implications for future numerical and experimental works.Keywords: aspect ratio, flexible cylinder, vortex-shedding, VIV
Procedia PDF Downloads 4882191 Catalytic and Non-Catalytic Pyrolysis of Walnut Shell Waste to Biofuel: Characterisation of Catalytic Biochar and Biooil
Authors: Saimatun Nisa
Abstract:
Walnut is an important export product from the Union Territory of Jammy and Kashmir. After extraction of the kernel, the walnut shell forms a solid waste that needs to be managed. Pyrolysis is one interesting option for the utilization of this walnut waste. In this study microwave pyrolysis reactor is used to convert the walnut shell biomass into its value-added products. Catalytic and non-catalytic conversion of walnut shell waste to oil, gas and char was evaluated using a Co-based catalyst. The catalyst was characterized using XPS and SEM analysis. Pyrolysis temperature, reaction time, particle size and sweeping gas (N₂) flow rate were set in the ranges of 400–600 °C, 40 min, <0.6mm to < 4.75mm and 300 ml min−1, respectively. The heating rate was fixed at 40 °C min−1. Maximum gas yield was obtained at 600 °C, 40 min, particle size range 1.18-2.36, 0.5 molar catalytic as 45.2%. The liquid product catalytic and non-catalytic was characterized by GC–MS analyses. In addition, the solid product was analyzed by means of FTIR & SEM.Keywords: walnut shell, biooil, biochar, microwave pyrolysis
Procedia PDF Downloads 522190 A Comparative Human Rights Analysis of the Securitization of Migration in the Fight against Terrorism in Europe: An Evaluation of Belgium
Authors: Louise Reyntjens
Abstract:
The last quarter of the twentieth century was characterized by the emergence of a new kind of terrorism: religiously-inspired terrorism. Islam finds itself at the heart of this new wave, considering the number of international attacks committed by Islamic-inspired perpetrators. With religiously inspired terrorism as an operating framework, governments increasingly rely on immigration law to counter such terrorism. Immigration law seems particularly useful because its core task consists of keeping ‘unwanted’ people out. Islamic terrorists more often than not have an immigrant background and will be subject to immigration law. As a result, immigration law becomes more and more ‘securitized’. The European migration crisis has reinforced this trend. The research explores the human rights consequences of immigration law’s securitization in Europe. For this, the author selected four European countries for a comparative study: Belgium, France, the United Kingdom and Sweden. All these countries face similar social and security issues but respond very differently to them. The United Kingdom positions itself on the repressive side of the spectrum. Sweden on the other hand also introduced restrictions to its immigration policy but remains on the tolerant side of the spectrum. Belgium and France are situated in between. This contribution evaluates the situation in Belgium. Through a series of legislative changes, the Belgian parliament (i) greatly expanded the possibilities of expelling foreign nationals for (vaguely defined) reasons of ‘national security’; (ii) abolished almost all procedural protection associated with this decision (iii) broadened, as an extra security measure, the possibility of depriving individuals condemned of terrorism of their Belgian nationality. Measures such as these are obviously problematic from a human rights perspective; they jeopardize the principle of legality, the presumption of innocence, the right to protection of private and family life and the prohibition on torture. Moreover, this contribution also raises questions about the efficacy of immigration law’s suitability as a counterterrorism instrument. Is it a legitimate step, considering the type of terrorism we face today? Or, is it merely a strategic move, considering the broader maneuvering space immigration law offers and the lack of political resistance governments receive when infringing the rights of foreigners? Even more so, figures demonstrate that today’s terrorist threat does not necessarily stem from outside our borders. Does immigration law then still absorb - if it has ever done so (completely) - the threat? The study’s goal is to critically assess, from a human rights perspective, the counterterrorism strategies European governments have adopted. As most governments adopt a variation of the same core concepts, the study’s findings will hold true even beyond the four countries addressed.Keywords: Belgium, counterterrorism strategies, human rights, immigration law
Procedia PDF Downloads 1062189 Numerical Simulation of the Flow around Wing-In-Ground Effect (WIG) Craft
Authors: A. Elbatran, Y. Ahmed, A. Radwan, M. Ishak
Abstract:
The use of WIG craft is representing an ambitious technology that will support in reducing time, effort, and money of the conventional marine transportation in the future. This paper investigates the aerodynamic characteristic of compound wing-in-ground effect (WIG) craft model. Drag coefficient, lift coefficient and Lift and drag ratio were studied numerically with respect to the ground clearance and the wing angle of attack. The modifications of the wing has been done in order to investigate the most suitable wing configuration that can increase the wing lift-to-drag ratio at low ground clearance. A numerical investigation was carried out in this research work using finite volume Reynolds-Averaged Navier-Stokes Equations (RANSE) code ANSYS CFX, Validation was carried out by using experiments. The experimental and the numerical results concluded that the lift to drag ratio decreased with the increasing of the ground clearance.Keywords: drag Coefficient, ground clearance, navier-stokes, WIG
Procedia PDF Downloads 3802188 Performance of Bimetallic Catalyst in the Oxidation of Volatile Organic Compounds
Authors: Faezeh Aghazadeh
Abstract:
The catalytic activity of Pt/γ-Al₂O₃ and Pt-Fe/γ-Al₂O₃ catalysts was investigated to bring about the complete oxidation of 2-Propanol. Among them, Pt-Fe/γ-Al₂O₃ was found to be the most promising catalyst based on activity. The catalysts were characterized by (XRD), (SEM), (TEM) and ICP-AES techniques. Iron loadings on Pt/γ-Al₂O₃ had a great effect on catalytic activity, and Pt-Fe/γ-Al₂O₃ (1.75 wt% Fe) catalyst at calcination temperature 300°C was observed to be the most active, which might be contributed to the favorable synergetic effects between Pt and Fe, high activity and the well-dispersed bimetallic phase. The combustion of 2-Propanol in the vapor phase was carried out in a conventional flow U-shape glass reactor used in the differential mode at atmospheric pressure. 2-Propanol was analyzed by a gas chromatograph VARIAN 3800 CX equipped with an FID. As observed, better performance and activity were observed for Pt-Fe/Al₂O₃ bimetallic catalyst. These results indicate that the high dispersion on support gives a positive effect on catalytic activity.Keywords: volatile organic compounds, bimetallic catalyst, catalytic activity, low temperature
Procedia PDF Downloads 1462187 Effect of Channel Cross Section Shape on Convective Heat Transfer Coefficient of Nanofluid Flow
Authors: Mohammad Reza Salimpour, Amir Dehshiri
Abstract:
In the present article, we investigate experimental laminar forced convective heat transfer specifications of TiO2/water nanofluids through conduits with different cross sections. We check the effects of different parameters such as cross sectional shape, Reynolds number and concentration of nanoparticles in stable suspension on increasing convective heat transfer by designing and assembling of an experimental apparatus. The results demonstrate adding a little amount of nanoparticles to the base fluid improves heat transfer behavior in conduits. Moreover, conduit with circular cross-section has better performance compared to the square and triangular cross sections. However, conduits with square and triangular cross sections have more relative heat transfer enhancement than conduit with circular cross section.Keywords: nanofluid, cross-sectional shape, TiO2, convection
Procedia PDF Downloads 4582186 Comparison Between PID and PD Controllers for 4 Cable-Based Robots
Authors: Fouad Inel, Lakhdar Khochemane
Abstract:
This article presents a comparative response specification performance between two controllers of three and four cable based robots for various applications. The main objective of this work is: the first is to use the direct and inverse geometric model to study and simulate the end effector position of the robot with three and four cables. A graphical user interface has been implemented in order to visualizing the position of the robot. Secondly, we present the determination of static and dynamic tensions and lengths of cables required to flow different trajectories. At the end, we study the response of our systems in closed loop with a Proportional-IntegratedDerivative (PID) and Proportional-Integrated (PD) controllers then this last are compared the results of the same examples using MATLAB/Simulink; we found that the PID method gives the better performance, such as rapidly speed response, settling time, compared to PD controller.Keywords: dynamic modeling, geometric modeling, graphical user interface, open loop, parallel cable-based robots, PID/PD controllers
Procedia PDF Downloads 4212185 Performance Evaluation of Extruded-type Heat sinks Used in Inverter for Solar Power Generation
Authors: Jung Hyun Kim, Gyo Woo Lee
Abstract:
In this study, heat release performances of the three extruded-type heat sinks can be used in the inverter for solar power generation were evaluated. Numbers of fins in the heat sinks (namely E-38, E-47 and E-76) were 38, 47 and 76, respectively. Heat transfer areas of them were 1.8, 1.9 and 2.8 m2. The heat release performances of E-38, E-47, and E-76 heat sinks were measured as 79.6, 81.6, and 83.2%, respectively. The results of heat release performance show that the larger amount of heat transfer area the higher heat release rate. While on the other, in this experiment, variations of the mass flow rates caused by different cross-sectional areas of the three heat sinks may not be the major parameter of the heat release. Despite the 47.4% increment of heat transfer area of E-76 heat sink than that of E-47 one, its heat release rate was higher by only 2.0%; this suggests that its heat transfer area need to be optimized.Keywords: solar Inverter, heat sink, forced convection, heat transfer, performance evaluation
Procedia PDF Downloads 4672184 GIS Application in Surface Runoff Estimation for Upper Klang River Basin, Malaysia
Authors: Suzana Ramli, Wardah Tahir
Abstract:
Estimation of surface runoff depth is a vital part in any rainfall-runoff modeling. It leads to stream flow calculation and later predicts flood occurrences. GIS (Geographic Information System) is an advanced and opposite tool used in simulating hydrological model due to its realistic application on topography. The paper discusses on calculation of surface runoff depth for two selected events by using GIS with Curve Number method for Upper Klang River basin. GIS enables maps intersection between soil type and land use that later produces curve number map. The results show good correlation between simulated and observed values with more than 0.7 of R2. Acceptable performance of statistical measurements namely mean error, absolute mean error, RMSE, and bias are also deduced in the paper.Keywords: surface runoff, geographic information system, curve number method, environment
Procedia PDF Downloads 2822183 Synthesis and in-vitro Evaluation of Quinozolines as Potent EGFR Inhibitor
Authors: Vinaya Kambappa, Chinnadurai Mani, Komaraiah Palle
Abstract:
Non-small cell-lung cancer (NSCLC) cells have increased expression of EGFR, which makes them a potential target for cancer therapy. Based on molecular docking and previous reports, we designed and synthesized quinazoline derivatives as potent EGFR inhibitors. Among the derivatives, three compounds showed good antiproliferative activity against A-549 and H-1299 cells. Furthermore, these compounds inhibited EGFR signaling exhibiting diminishing p-EGFR and its downstream proteins like p-Akt, p-Erk1/2, and p-mTOR; however, it did not alter the levels of EGFR, Akt, Erk1/2 and mTOR proteins. Flow cytometric analysis indicated the accumulation of cells at G1 phase suggesting induction of apoptosis, which was further confirmed by annexin V/propidium iodide staining. Our study suggested that quinazoline scaffold can be developed as novel EGFR kinase inhibitors for cancer therapy.Keywords: apoptosis, non-small cell-lung cancer cells, EGFR, quinazoline
Procedia PDF Downloads 187