Search results for: haze number
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9898

Search results for: haze number

5248 Analysis of Cyber Activities of Potential Business Customers Using Neo4j Graph Databases

Authors: Suglo Tohari Luri

Abstract:

Data analysis is an important aspect of business performance. With the application of artificial intelligence within databases, selecting a suitable database engine for an application design is also very crucial for business data analysis. The application of business intelligence (BI) software into some relational databases such as Neo4j has proved highly effective in terms of customer data analysis. Yet what remains of great concern is the fact that not all business organizations have the neo4j business intelligence software applications to implement for customer data analysis. Further, those with the BI software lack personnel with the requisite expertise to use it effectively with the neo4j database. The purpose of this research is to demonstrate how the Neo4j program code alone can be applied for the analysis of e-commerce website customer visits. As the neo4j database engine is optimized for handling and managing data relationships with the capability of building high performance and scalable systems to handle connected data nodes, it will ensure that business owners who advertise their products at websites using neo4j as a database are able to determine the number of visitors so as to know which products are visited at routine intervals for the necessary decision making. It will also help in knowing the best customer segments in relation to specific goods so as to place more emphasis on their advertisement on the said websites.

Keywords: data, engine, intelligence, customer, neo4j, database

Procedia PDF Downloads 181
5247 Research on the Application of Renewability in the Construction Model of Zhejiang Rural Revitalization

Authors: Zheng Junchao, Wang Zhu

Abstract:

With the advancement of China's urbanization process, the Chinese government has put forward the strategy of rural revitalization which is aiming at realizing the comprehensive integration of urban and rural areas and the comprehensive revitalization of rural areas. The path of rural revitalization in Zhejiang province put forward a typical model from four dimensions: suburban area, plain, island and mountain area. Research methods include on-the-spot investigation, visiting a number of successful demonstration villages in Zhejiang and interviewing village officials. Based on the location conditions, resource endowments, industrial forms and development foundations of Zhejiang Province, this paper introduces in detail the model of rural revitalization in Zhejiang Province and the challenges it encounters, as well as the role of building construction. The rural development model of Zhejiang province makes the rural culture flourish. Taking the construction of rural scenic spots as the carrier, the rural culture, and natural landscape are constantly improved. It provides a model and template for the country's rural revitalization. The promotion of Zhejiang rural revitalization model will improve the current rural landscape, living standard and industrial structure, which will narrow the urban-rural gap greatly.

Keywords: comprehensive rural revitalization, Zhejiang model, reproducible, comprehensive integration

Procedia PDF Downloads 182
5246 In Search of Zero Beta Assets: Evidence from the Sukuk Market

Authors: Andrea Paltrinieri, Alberto Dreassi, Stefano Miani, Alex Sclip

Abstract:

The financial crises caused a collapse in prices of most asset classes, raising the attention on alternative investments such as Sukuk, a smaller, fast growing but often misunderstood market. We study diversification benefits of Sukuk, their correlation with other asset classes and the effects of their inclusion in investment portfolios of institutional and retail investors, through a comprehensive comparison of their risk/return profiles during and after the financial crisis. We find a beneficial performance adjusted for the specific volatility together with a lower correlation especially during the financial crisis. The distribution of Sukuk returns is positively skewed and leptokurtic, with a risk/return profile similarly to high yield bonds. Overall, our results suggest that Sukuk present diversification opportunities, a significant volatility-adjusted performance and lower correlations especially during the financial crisis. Our findings are relevant for a number of institutional investors. Long term investors, such as life insurers would benefit from Sukuk’s protective features during financial crisis yet keeping return and growth opportunities, whereas banks would gain due to their role of placers, advisors, market makers or underwriters.

Keywords: sukuk, zero beta asset, asset allocation, sukuk market

Procedia PDF Downloads 465
5245 Efficient High Fidelity Signal Reconstruction Based on Level Crossing Sampling

Authors: Negar Riazifar, Nigel G. Stocks

Abstract:

This paper proposes strategies in level crossing (LC) sampling and reconstruction that provide high fidelity signal reconstruction for speech signals; these strategies circumvent the problem of exponentially increasing number of samples as the bit-depth is increased and hence are highly efficient. Specifically, the results indicate that the distribution of the intervals between samples is one of the key factors in the quality of signal reconstruction; including samples with short intervals do not improve the accuracy of the signal reconstruction, whilst samples with large intervals lead to numerical instability. The proposed sampling method, termed reduced conventional level crossing (RCLC) sampling, exploits redundancy between samples to improve the efficiency of the sampling without compromising performance. A reconstruction technique is also proposed that enhances the numerical stability through linear interpolation of samples separated by large intervals. Interpolation is demonstrated to improve the accuracy of the signal reconstruction in addition to the numerical stability. We further demonstrate that the RCLC and interpolation methods can give useful levels of signal recovery even if the average sampling rate is less than the Nyquist rate.

Keywords: level crossing sampling, numerical stability, speech processing, trigonometric polynomial

Procedia PDF Downloads 133
5244 Numerical Heat Transfer Performance of Water-Based Graphene Nanoplatelets

Authors: Ahmad Amiri, Hamed K. Arzani, S. N. Kazi, B. T. Chew

Abstract:

Since graphene nanoplatelet (GNP) is a promising material due to desirable thermal properties, this paper is related to the thermophysical and heat transfer performance of covalently functionalized GNP-based water/ethylene glycol nanofluid through an annular channel. After experimentally measuring thermophysical properties of prepared samples, a computational fluid dynamics study has been carried out to examine the heat transfer and pressure drop of well-dispersed and stabilized nanofluids. The effect of concentration of GNP and Reynolds number at constant wall temperature boundary condition under turbulent flow regime on convective heat transfer coefficient has been investigated. Based on the results, for different Reynolds numbers, the convective heat transfer coefficient of the prepared nanofluid is higher than that of the base fluid. Also, the enhancement of convective heat transfer coefficient and thermal conductivity increase with the increase of GNP concentration in base-fluid. Based on the results of this investigation, there is a significant enhancement on the heat transfer rate associated with loading well-dispersed GNP in base-fluid.

Keywords: nanofluid, turbulent flow, forced convection flow, graphene, annular, annulus

Procedia PDF Downloads 341
5243 A Study for the Effect of Fire Initiated Location on Evacuation Success Rate

Authors: Jin A Ryu, Hee Sun Kim

Abstract:

As the number of fire accidents is gradually raising, many studies have been reported on evacuation. Previous studies have mostly focused on evaluating the safety of evacuation and the risk of fire in particular buildings. However, studies on effects of various parameters on evacuation have not been nearly done. Therefore, this paper aims at observing evacuation time under the effect of fire initiated location. In this study, evacuation simulations are performed on a 5-floor building located in Seoul, South Korea using the commercial program, Fire Dynamics Simulator with Evacuation (FDS+EVAC). Only the fourth and fifth floors are modeled with an assumption that fire starts in a room located on the fourth floor. The parameter for evacuation simulations is location of fire initiation to observe the evacuation time and safety. Results show that the location of fire initiation is closer to exit, the more time is taken to evacuate. The case having the nearest location of fire initiation to exit has the lowest ratio of successful occupants to the total occupants. In addition, for safety evaluation, the evacuation time calculated from computer simulation model is compared with the tolerable evacuation time according to code in Japan. As a result, all cases are completed within the tolerable evacuation time. This study allows predicting evacuation time under various conditions of fire and can be used to evaluate evacuation appropriateness and fire safety of building.

Keywords: fire simulation, evacuation simulation, temperature, evacuation safety

Procedia PDF Downloads 325
5242 Development of K-Factor for Road Geometric Design: A Case Study of North Coast Road in Java

Authors: Edwin Hidayat, Redi Yulianto, Disi Hanafiah

Abstract:

On the one hand, parameters which are used for determining the number of lane on the new road construction are average annual average daily traffic (AADT) and peak hour factor (K-factor). On the other hand, the value of K-factor listed in the guidelines and manual for road planning in Indonesia is a value of adoption or adaptation from foreign guidelines or manuals. Thus, the value is less suitable for Indonesian condition due to differences in road conditions, vehicle type, and driving behavior. The purpose of this study is to provide an example on how to determine k-factor values at a road segment with particular conditions in north coast road, West Java. The methodology is started with collecting traffic volume data for 24 hours over 365 days using PLATO (Automated Traffic Counter) with the approach of video image processing. Then, the traffic volume data is divided into per hour and analyzed by comparing the peak traffic volume in the 30th hour (or other) with the AADT in the same year. The analysis has resulted that for the 30th peak hour the K-factor is 0.97. This value can be used for planning road geometry or evaluating the road capacity performance for the 4/2D interurban road.

Keywords: road geometry, K-factor, annual average daily traffic, north coast road

Procedia PDF Downloads 146
5241 Urban Resilience: Relation between COVID-19 and Urban Environment in Amman City

Authors: Layla Mujahed

Abstract:

COVID-19 is an exam for all the city’s systems. It shows many gaps in the systems such as healthcare, economic, social, and environment. This pandemic is paving for a new era, an era of technology and it has changed people’s lives, such as physical, and emotional changes, and converting communication into digitalized. The effect of COVID-19 has covered all urban city parts. COVID-19 will not be the last pandemic our cities will face. For that, more researches focus on enhancing the quality of the urban environment. This pandemic encourages a rethinking of the environment’s role, especially in cities. Cities are trying to provide the best suitable strategies and regulations to prevent the spread of COVID-19, and an example of that is Amman city. Amman has a high increment in the number of COVID-19 infected people, while it has controlled the situation for months. For that, this paper studies the relation between COVID-19 and urban environmental studies cases about cities around the world, and learns from their models to face COVID-19. In Amman, people’s behavior has changed towards public transportation and public green spaces. N­ew governmental regulations focus on increasing people’s mental awareness, supporting local businesses, and enhancing neighborhood planning that can help Amman to face any future pandemics.

Keywords: COVID-19, urban environment, urban planning, urban resilience

Procedia PDF Downloads 107
5240 Set-point Performance Evaluation of Robust ‎Back-Stepping Control Design for a Nonlinear ‎Electro-‎Hydraulic Servo System

Authors: Maria Ahmadnezhad, Seyedgharani Ghoreishi ‎

Abstract:

Electrohydraulic servo system have been used in industry in a wide ‎number of applications. Its ‎dynamics are highly nonlinear and also ‎have large extent of model uncertainties and external ‎disturbances. ‎In this thesis, a robust back-stepping control (RBSC) scheme is ‎proposed to overcome ‎the problem of disturbances and system ‎uncertainties effectively and to improve the set-point ‎performance ‎of EHS systems. In order to implement the proposed control ‎scheme, the system ‎uncertainties in EHS systems are considered as ‎total leakage coefficient and effective oil volume. In ‎addition, in ‎order to obtain the virtual controls for stabilizing system, the ‎update rule for the ‎system uncertainty term is induced by the ‎Lyapunov control function (LCF). To verify the ‎performance and ‎robustness of the proposed control system, computer simulation of ‎the ‎proposed control system using Matlab/Simulink Software is ‎executed. From the computer ‎simulation, it was found that the ‎RBSC system produces the desired set-point performance and ‎has ‎robustness to the disturbances and system uncertainties of ‎EHS systems.‎

Keywords: electro hydraulic servo system, back-stepping control, robust back-‎stepping control, Lyapunov redesign‎

Procedia PDF Downloads 983
5239 Displacement Situation in Federally Administered Tribal Areas of Pakistan: Issues and Challenges

Authors: Sohail Ahmad, Inayat Kaleem

Abstract:

Federally Administered Tribal Area(FATA) of Pakistan is one of the most neglected regions in the world as far as development is concerned. It has been the hub of all sorts of illegal activities including militancy and export of terrorism. Therefore, it became inevitable for the government of Pakistan to take action against militants through military operations. Small and large scale military operations are being taken against the non-state actors in FATA with continuity. Over the years, hundreds of thousands have been displaced from the tribal areas of the country. Moreover, military operation Zarb-e-Azb has been launched in North Waziristan Agency in June 2014 to counter militancy across the Af-Pak border region. Though successful in curbing militancy, the operation has displaced around 0.5 million people from the area. Most of them opt to take shelter in the government installed shelter camps, some of them take refuge outside tent villages in the country while some of them prefer to cross into Afghanistan rather their own country Pakistan. This paper will evaluate how the influx of these internally displaced persons in the country is influencing the socio-economic situation of not only the displaced but of the hosting areas as well. Secondly, attention would be given to gauge the impact of such a huge number of displaced population on the law and order and security situation in the host areas.

Keywords: Af-Pak, federally administered tribal area, IDPs, internal displacement, Pakistan

Procedia PDF Downloads 297
5238 Epileptic Seizure Onset Detection via Energy and Neural Synchronization Decision Fusion

Authors: Marwa Qaraqe, Muhammad Ismail, Erchin Serpedin

Abstract:

This paper presents a novel architecture for a patient-specific epileptic seizure onset detector using scalp electroencephalography (EEG). The proposed architecture is based on the decision fusion calculated from energy and neural synchronization related features. Specifically, one level of the detector calculates the condition number (CN) of an EEG matrix to evaluate the amount of neural synchronization present within the EEG channels. On a parallel level, the detector evaluates the energy contained in four EEG frequency subbands. The information is then fed into two independent (parallel) classification units based on support vector machines to determine the onset of a seizure event. The decisions from the two classifiers are then combined together according to two fusion techniques to determine a global decision. Experimental results demonstrate that the detector based on the AND fusion technique outperforms existing detectors with a sensitivity of 100%, detection latency of 3 seconds, while it achieves a 2:76 false alarm rate per hour. The OR fusion technique achieves a sensitivity of 100%, and significantly improves delay latency (0:17 seconds), yet it achieves 12 false alarms per hour.

Keywords: epilepsy, EEG, seizure onset, electroencephalography, neuron, detection

Procedia PDF Downloads 458
5237 The Diversity of Black Flies in Peninsular Malaysia

Authors: C. D. Chen, H. Takaoka, Z. Ya’cob, V. L. Low, K. W. Lau, M. Sofian-Azirun

Abstract:

Adult black flies (Diptera: Simuliidae) are small (1.5-6.0 mm long), two-winged insects, and are well known as one of the biting flies of medical and veterinary importance. Female of certain species, when they bite and take blood, not only cause severe skin diseases to human and cattle but also play a role as vectors of viral, protozoan and filarial diseases in humans and animals. Black flies also attract environmental biologist and ecologist because their immature states breed only in clean running fresh waters, and larvae are one of the principal processors of plant debris in streams. All these researches on medical and ecological aspects of black flies could not be reliably proceeded without sufficient basic knowledge of the fauna of black flies established by traditional but still important morphotaxonomy. Previously, only 39 species of black flies were recorded from Peninsular Malaysia, all of which are classified into four subgenus (Daviesellum, Gomphostilbia, Nevermannia and Simulium) of the genus Simulium. We carried out faunal surveys and taxonomic works of black flies in Peninsular Malaysia since November 2010. A total of 17 new species and 4 newly recorded species were collected. This increased the number of the described species of black flies in Peninsular Malaysia from 39 to 60. Our results suggest that a much higher diverse nature of black flies in Peninsular Malaysia will be clarified by further extensive surveys.

Keywords: black flies, Simulium, Nevermannia, feuerborni species-group

Procedia PDF Downloads 449
5236 Flotation Recovery of Gold-Loaded Fine Activated Carbon Using Emulsified Diesel and Kerosene as Collectors

Authors: Emmanuel Jr. Ballad, Herman Mendoza

Abstract:

The recovery of fine activated carbon with adsorbed gold in the cyanidation tailings of a small-scale gold plant was investigated due to the high amount of gold present. In the study, collectors that were used are kerosene and diesel. Emulsification of the oils was done to improve its collecting property, thus also the recovery. It was found out that the best hydrophile lypophile balance (HLB) of emulsified diesel and kerosene oil is 13 and 12 respectively. The amount of surfactants (SPAN 20 and TWEEN 20) for the best stability of the emulsified oils was found to be 10% in both kerosene and diesel. Optical microscopy showed that the oil dispersion in the water forms spherical droplets like features. The higher the stability, the smaller the droplets and their number were increasing. The smaller droplets indicate better dispersion of oil in the water. Consequently, it will have a greater chance of oil and activated carbon particle interaction during flotation. Due to the interaction of dispersed oil phase with carbon, the hydrophobicity of the carbon will be improved and will be attached to the bubble. Thus, flotation recovery will be increased. Results showed that the recovery of the fine activated carbon using emulsified diesel or kerosene is three times more effective than using pure diesel or kerosene.

Keywords: emulsified oils, flotation, hydrophile lyophile balance, non-ionic surfactants

Procedia PDF Downloads 354
5235 An Improved K-Means Algorithm for Gene Expression Data Clustering

Authors: Billel Kenidra, Mohamed Benmohammed

Abstract:

Data mining technique used in the field of clustering is a subject of active research and assists in biological pattern recognition and extraction of new knowledge from raw data. Clustering means the act of partitioning an unlabeled dataset into groups of similar objects. Each group, called a cluster, consists of objects that are similar between themselves and dissimilar to objects of other groups. Several clustering methods are based on partitional clustering. This category attempts to directly decompose the dataset into a set of disjoint clusters leading to an integer number of clusters that optimizes a given criterion function. The criterion function may emphasize a local or a global structure of the data, and its optimization is an iterative relocation procedure. The K-Means algorithm is one of the most widely used partitional clustering techniques. Since K-Means is extremely sensitive to the initial choice of centers and a poor choice of centers may lead to a local optimum that is quite inferior to the global optimum, we propose a strategy to initiate K-Means centers. The improved K-Means algorithm is compared with the original K-Means, and the results prove how the efficiency has been significantly improved.

Keywords: microarray data mining, biological pattern recognition, partitional clustering, k-means algorithm, centroid initialization

Procedia PDF Downloads 175
5234 A New Fuzzy Fractional Order Model of Transmission of Covid-19 With Quarantine Class

Authors: Asma Hanif, A. I. K. Butt, Shabir Ahmad, Rahim Ud Din, Mustafa Inc

Abstract:

This paper is devoted to a study of the fuzzy fractional mathematical model reviewing the transmission dynamics of the infectious disease Covid-19. The proposed dynamical model consists of susceptible, exposed, symptomatic, asymptomatic, quarantine, hospitalized and recovered compartments. In this study, we deal with the fuzzy fractional model defined in Caputo’s sense. We show the positivity of state variables that all the state variables that represent different compartments of the model are positive. Using Gronwall inequality, we show that the solution of the model is bounded. Using the notion of the next-generation matrix, we find the basic reproduction number of the model. We demonstrate the local and global stability of the equilibrium point by using the concept of Castillo-Chavez and Lyapunov theory with the Lasalle invariant principle, respectively. We present the results that reveal the existence and uniqueness of the solution of the considered model through the fixed point theorem of Schauder and Banach. Using the fuzzy hybrid Laplace method, we acquire the approximate solution of the proposed model. The results are graphically presented via MATLAB-17.

Keywords: Caputo fractional derivative, existence and uniqueness, gronwall inequality, Lyapunov theory

Procedia PDF Downloads 88
5233 Energy Absorption of Circular Thin-Walled Tube with Curved-Crease Patterns under Axial Crushing

Authors: Grzegorz Dolzyk, Sungmoon Jung

Abstract:

Thin-walled tubes are commonly used as energy absorption devices for their excellent mechanical properties and high manufacturability. Techniques such as grooving and pre-folded origami shapes were introduced to circular and polygonal tubes to improve its energy absorption efficiency. This paper examines the energy absorption characteristics of circular tubes with pre-embedded curved-crease pattern. Set of numerical analyzes were conducted with different grooving patterns for tubes with various diameter (D) to thickness (t) ratio. It has been found that even very shallow grooving can positively affect thin wall tubes, leading to increased energy absorption and higher crushing load efficiency. The phenomenon is associated with nonsymmetric deformation that is usually observed for tubes with a high D/t ratio ( > 90). Grooving can redirect a natural mode of post-buckling deformation to a one with a higher number of lobes such that its beneficial and more stable. Also, the opposite effect can be achieved, and highly disrupted deformation can be a cause of reduced energy absorption capabilities. Curved-crease engraved patterns can be used to stabilize and change a form of hazardous post-buckling deformation.

Keywords: axial crushing, energy absorption, grooving, thin-wall structures

Procedia PDF Downloads 127
5232 Numerical Study on Parallel Rear-Spoiler on Super Cars

Authors: Anshul Ashu

Abstract:

Computers are applied to the vehicle aerodynamics in two ways. One of two is Computational Fluid Dynamics (CFD) and other is Computer Aided Flow Visualization (CAFV). Out of two CFD is chosen because it shows the result with computer graphics. The simulation of flow field around the vehicle is one of the important CFD applications. The flow field can be solved numerically using panel methods, k-ε method, and direct simulation methods. The spoiler is the tool in vehicle aerodynamics used to minimize unfavorable aerodynamic effects around the vehicle and the parallel spoiler is set of two spoilers which are designed in such a manner that it could effectively reduce the drag. In this study, the standard k-ε model of the simplified version of Bugatti Veyron, Audi R8 and Porsche 911 are used to simulate the external flow field. Flow simulation is done for variable Reynolds number. The flow simulation consists of three different levels, first over the model without a rear spoiler, second for over model with single rear spoiler, and third over the model with parallel rear-spoiler. The second and third level has following parameter: the shape of the spoiler, the angle of attack and attachment position. A thorough analysis of simulations results has been found. And a new parallel spoiler is designed. It shows a little improvement in vehicle aerodynamics with a decrease in vehicle aerodynamic drag and lift. Hence, it leads to good fuel economy and traction force of the model.

Keywords: drag, lift, flow simulation, spoiler

Procedia PDF Downloads 470
5231 Prediction of Saturated Hydraulic Conductivity Dynamics in an Iowan Agriculture Watershed

Authors: Mohamed Elhakeem, A. N. Thanos Papanicolaou, Christopher Wilson, Yi-Jia Chang

Abstract:

In this study, a physically-based, modelling framework was developed to predict saturated hydraulic conductivity (KSAT) dynamics in the Clear Creek Watershed (CCW), Iowa. The modelling framework integrated selected pedotransfer functions and watershed models with geospatial tools. A number of pedotransfer functions and agricultural watershed models were examined to select the appropriate models that represent the study site conditions. Models selection was based on statistical measures of the models’ errors compared to the KSAT field measurements conducted in the CCW under different soil, climate and land use conditions. The study has shown that the predictions of the combined pedotransfer function of Rosetta and the Water Erosion Prediction Project (WEPP) provided the best agreement to the measured KSAT values in the CCW compared to the other tested models. Therefore, Rosetta and WEPP were integrated with the Geographic Information System (GIS) tools for visualization of the data in forms of geospatial maps and prediction of KSAT variability in CCW due to the seasonal changes in climate and land use activities.

Keywords: saturated hydraulic conductivity, pedotransfer functions, watershed models, geospatial tools

Procedia PDF Downloads 238
5230 Crisis Communication at Destinations: A Study for Tourism Managers

Authors: Volkan Altintas, Burcu Oksuz

Abstract:

Tourism industry essentially requires effective crisis management and crisis communication skills, as it is extremely vulnerable to crises. In terms of destinations, tourism crises cause dramatic decreases in the number of inbound tourists, impairment in the destination’s image, and decline in the level of preferability of the destination not only in the short but also in the long term. Therefore, any destination should be well prepared for crisis situation that may arise for various reasons. Currently, the advancement in communication technologies enables and facilitates information and experience to spread rapidly, and negative information and experiences tend to be shared to a further extent. Destinations are broadly exposed to the impacts of such communication stream. Turkey is almost continuously exposed to crises and their adverse impacts as a tourism destination, and thus requires effective crisis communication activities to be maintained. Hence, the approaches of tourism managers toward crisis communication and their proposals for addressing issues in question are important. This study intends to set forth the considerations of the managers serving in the tourism industry about crisis communication at destinations. The theoretical part of the study describes and explains crisis management and crisis communication at destinations; following which are provided the outcomes of the thorough in-depth interviews and discussions conducted for the establishment of the considerations of tourism managers. Managers indicated the role and importance of crisis communications in destinations.

Keywords: crisis communication, crisis management, destination, tourism managers

Procedia PDF Downloads 298
5229 Optimization of Pyrogallol Based Manganese / Ferroin Catalyzed Nonlinear Chemical Systems and Interaction with Monomeric and Polymeric Entities

Authors: Ghulam Mustafa Peerzada, Shagufta Rashid, Nadeem Bashir

Abstract:

These the influence of initial reagent concentrations on the Belousov-Zhabotinsky (BZ) system with Mn2+/Mn3+ as redox catalyst, inorganic bromate as oxidant and pyrogallol as organic substrate was studied. The reactions were monitored by potentiometery in oxidation reduction potential (ORP) mode. The aforesaid reagents were mixed with varying concentrations to evolve the optimal concentrations at which the reaction system exhibited better oscillations. The various oscillatory parameters such as induction period (tin), time period (tp), frequency (v), amplitude (A) and number of oscillations (n) were derived and the dependence of concentration of the reacting species on these oscillatory parameters was interpreted on the basis of the Field-Koros-Noyes mechanism. Ferroin based BZ system with pyrogallol as organic substrate was optimized under CSTR condition at temperature of 30±0.1oC Effect of molecules like monomer and polymer as additives to the system was checked and their interaction with the system was also studied. It has been observed that the monomer affects the time period, while the polymer has its effect on the amplitude of oscillations because of monomer’s interaction with the bromine and polymer’s with that of the Ferroin.

Keywords: Belousov Zhabotinsky reaction, oscillatory parameters, polymer, pyrogallol

Procedia PDF Downloads 296
5228 Optimization of Laser Doping Selective Emitter for Silicon Solar Cells

Authors: Meziani Samir, Moussi Abderrahmane, Chaouchi Sofiane, Guendouzi Awatif, Djema Oussama

Abstract:

Laser doping has a large potential for integration into silicon solar cell technologies. The ability to process local, heavily diffused regions in a self-aligned manner can greatly simplify processing sequences for the fabrication of selective emitter. The choice of laser parameters for a laser doping process with 532nm is investigated. Solid state lasers with different power and speed were used for laser doping. In this work, the aim is the formation of selective emitter solar cells with a reduced number of technological steps. In order to have a highly doped localized emitter region, we used a 532 nm laser doping. Note that this region will receive the metallization of the Ag grid by screen printing. For this, we use SOLIDWORKS software to design a single type of pattern for square silicon cells. Sheet resistances, phosphorus doping concentration and silicon bulk lifetimes of irradiated samples are presented. Additionally, secondary ion mass spectroscopy (SIMS) profiles of the laser processed samples were acquired. Scanning electron microscope and optical microscope images of laser processed surfaces at different parameters are shown and compared.

Keywords: laser doping, selective emitter, silicon, solar cells

Procedia PDF Downloads 79
5227 CSRFDtool: Automated Detection and Prevention of a Reflected Cross-Site Request Forgery

Authors: Alaa A. Almarzuki, Nora A. Farraj, Aisha M. Alshiky, Omar A. Batarfi

Abstract:

The number of internet users is dramatically increased every year. Most of these users are exposed to the dangers of attackers in one way or another. The reason for this lies in the presence of many weaknesses that are not known for native users. In addition, the lack of user awareness is considered as the main reason for falling into the attackers’ snares. Cross Site Request Forgery (CSRF) has placed in the list of the most dangerous threats to security in OWASP Top Ten for 2013. CSRF is an attack that forces the user’s browser to send or perform unwanted request or action without user awareness by exploiting a valid session between the browser and the server. When CSRF attack successes, it leads to many bad consequences. An attacker may reach private and personal information and modify it. This paper aims to detect and prevent a specific type of CSRF, called reflected CSRF. In a reflected CSRF, a malicious code could be injected by the attackers. This paper explores how CSRF Detection Extension prevents the reflected CSRF by checking browser specific information. Our evaluation shows that the proposed solution succeeds in preventing this type of attack.

Keywords: CSRF, CSRF detection extension, attackers, attacks

Procedia PDF Downloads 400
5226 Social Media Use and Social Connectedness

Authors: Jessica Torres, James W. Sturges

Abstract:

This correlational study explored the potential relationship between social media use and social connectedness. College students (n = 190) were surveyed using the revised Social Connectedness Scale (SCS-R) and were asked about the number of hours they used social media platforms such as Instagram, TikTok, Twitter, Snapchat, and Facebook. We also developed and administered a 14-item Social Media Use Scale (SMUS) to measure potentially maladaptive social media use, such as use that likely interfered with other activities. The SMUS was found to have good inter-item consistency (Cronbach’s alpha = .92) and was significantly correlated with hours of use, r(182) = .622, p < .001. As expected, we found that the SCS-R scores were inversely related to total hours of social media use, r(182) = -.188 (p < .005). This suggested that lots of time allocated to online interactions is negatively associated with social connectedness in general. Interestingly, however, higher social connectedness scores were associated specifically with Snapchat use, r(28) = .210, p = .004. This may have to do with the specific nature of the Snapchat experience and perhaps its original use for one-to-one communication. The use of other social media platforms (Tiktok, Instagram, Twitter) was not related to better social connectedness scores. Although we failed to find that scores on our measure of problem use (the SMUS) were correlated with social connectedness, we are hopeful that the SMUS will be of use in identifying patterns of maladaptive social media use that may have an impact on other important outcome measures of adaptive functioning and well-being.

Keywords: adaptive functioning, college students, social connectedness, social media use

Procedia PDF Downloads 66
5225 Near Shore Wave Manipulation for Electricity Generation

Authors: K. D. R. Jagath-Kumara, D. D. Dias

Abstract:

The sea waves carry thousands of GWs of power globally. Although there are a number of different approaches to harness offshore energy, they are likely to be expensive, practically challenging and vulnerable to storms. Therefore, this paper considers using the near shore waves for generating mechanical and electrical power. It introduces two new approaches, the wave manipulation and using a variable duct turbine, for intercepting very wide wave fronts and coping with the fluctuations of the wave height and the sea level, respectively. The first approach effectively allows capturing much more energy yet with a much narrower turbine rotor. The second approach allows using a rotor with a smaller radius but captures energy of higher wave fronts at higher sea levels yet preventing it from totally submerging. To illustrate the effectiveness of the approach, the paper contains a description and the simulation results of a scale model of a wave manipulator. Then, it includes the results of testing a physical model of the manipulator and a single duct, axial flow turbine, in a wave flume in the laboratory. The paper also includes comparisons of theoretical predictions, simulation results and wave flume tests with respect to the incident energy, loss in wave manipulation, minimal loss, brake torque and the angular velocity.

Keywords: near-shore sea waves, renewable energy, wave energy conversion, wave manipulation

Procedia PDF Downloads 458
5224 Digital Preservation Policies in the Institutional Repositories of Brazilian Federal Universities

Authors: Laerte Pereira da Silva Júnior, Maria Manuel Borges

Abstract:

Institutional Repositories (IR) are complex constructs that depend on political, cultural and technological aspects. Because IRs are a mirror of the organization's intellectual production, their main function is to make that production available worldwide, and also to consider its long term preservation. To this end, there is a need to define clearly the digital preservation policies supported by political decisions. There are several guidelines about the definition of digital preservation policies focusing in different themes from preservation planning to rights and restriction management, sustainability planning, etc., but this work aims to verify the implementation of digital preservation policies on the Institutional Repositories of the Federal Universities of Brazil. The methodology used was to check the information available on the websites of the IRs selected against two fields of the OpenDOAR, policies and OpenDOAR ID, to verify the existence of digital preservation policies. For this purpose a sample of the 21 of the 25 IRs registered at the Directory of Open Access Repositories (DOAR) was used, which is about 1/3 rd of the total of the brazilian universities. The 4 IRs that presented no information by the OpenDOAR team were desconsidered. The main conclusion is that most of the IRs of these universities have no polices clearly stated or no policies at all, and that there is a need to include these concerns at the top level management of IRs. The number of initiatives in digital preservation policies around the world stress the need of awareness of its importance in Brazil and requires measures to raise this awareness.

Keywords: Brazil, digital preservation policies, institutional repositories, openDOAR

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5223 Applied Complement of Probability and Information Entropy for Prediction in Student Learning

Authors: Kennedy Efosa Ehimwenma, Sujatha Krishnamoorthy, Safiya Al‑Sharji

Abstract:

The probability computation of events is in the interval of [0, 1], which are values that are determined by the number of outcomes of events in a sample space S. The probability Pr(A) that an event A will never occur is 0. The probability Pr(B) that event B will certainly occur is 1. This makes both events A and B a certainty. Furthermore, the sum of probabilities Pr(E₁) + Pr(E₂) + … + Pr(Eₙ) of a finite set of events in a given sample space S equals 1. Conversely, the difference of the sum of two probabilities that will certainly occur is 0. This paper first discusses Bayes, the complement of probability, and the difference of probability for occurrences of learning-events before applying them in the prediction of learning objects in student learning. Given the sum of 1; to make a recommendation for student learning, this paper proposes that the difference of argMaxPr(S) and the probability of student-performance quantifies the weight of learning objects for students. Using a dataset of skill-set, the computational procedure demonstrates i) the probability of skill-set events that have occurred that would lead to higher-level learning; ii) the probability of the events that have not occurred that requires subject-matter relearning; iii) accuracy of the decision tree in the prediction of student performance into class labels and iv) information entropy about skill-set data and its implication on student cognitive performance and recommendation of learning.

Keywords: complement of probability, Bayes’ rule, prediction, pre-assessments, computational education, information theory

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5222 Human Security: The Boko Haram Menace in Northern Nigeria in the 21st Century

Authors: Jimoh Yusuf Amuda

Abstract:

Human security is a great panacea for sustainable development of world societies. Today the whole globe cum human species is living in nightmares of insecurity. This is due to acts of terrorism by various terrorists’ organization worldwide. The situation is on the increase daily. The number of lives and properties lost to religious insurgency cannot be quantifiably analyzed. It is on this note that this paper examine the book haram menace in northern Nigerian vis-à-vis it’s threat to the existence of human lives. The methodology applied for this research is the multi-disciplinary approach, the use journal articles, news papers, magazines, oral interview. Field trips to areas of terrorist attack and the use of text books. The following recommendations were made base on the findings. First of all the Nigerian government should declare total war on the book haram terrorist, then secondly the source of armament coming to this terrorist should be blocked, thirdly the European world should also place an arms embargo on terrorist source arms demands, also security agencies-police, the military, immigration, customs, state security service should work hand-in-hand, in a security tight measures to reduce the penetration of insurgent into the society.

Keywords: human, insecurity, security, terrorism

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5221 Role of Facade in Sustainability Enhancement of Contemporary Iranian Buildings

Authors: H. Nejadriahi

Abstract:

A growing demand for sustainability makes sustainability as one of the significant debates of nowadays. Energy saving is one of the main criteria to be considered in the context of sustainability. Reducing energy use in buildings is one of the most important ways to reduce humans’ overall environmental impact. Taking this into consideration, study of different design strategies, which can assist in reducing energy use and subsequently improving the sustainability level of today's buildings would be an essential task. The sustainability level of a building is highly affected by the sustainability performance of its components. One of the main building components, which can have a great impact on energy saving and sustainability level of the building, is its facade. The aim of this study is to investigate on the role of facade in sustainability enhancement of the contemporary buildings of Iran. In this study, the concept of sustainability in architecture, the building facades, and their relationship to sustainability are explained briefly. Following that, a number of contemporary Iranian buildings are discussed and analyzed in terms of different design strategies used in their facades in accordance to the sustainability concepts. The methods used in this study are descriptive and analytic. The results of this paper would assist in generating a wider vision and a source of inspiration for the current designers to design and create environmental and sustainable buildings for the future.

Keywords: building facade, contemporary buildings, Iran, sustainability

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5220 Determinants for Transportation Services in Addis Ababa City

Authors: Yared Yitagesu Tilahun

Abstract:

Every nation, developed or developing, relies on transportation, but Addis Abeba City's transportation service is impacted by a number of variables. The current study's objectives are to determine the factors that influence transportation and gauge consumer satisfaction with such services in Addis Abeba. Customers and employees of Addis Ababa's transportation service authority would be the study's target group. 40 workers of the authority would be counted as part of the 310 000 clients that make up the population of the searcher service. Using a straightforward random selection technique, the researcher only chose 99 customers and 28 staff from this enormous group due to the considerable cost and time involved. Data gathering and analysis options included both quantitative and qualitative approaches. The results of this poll show that young people between the ages of 18 and 25 make up the majority of respondents (51.6%). The majority of employees and customers indicated that they are not satisfied with Addis Ababa's overall transportation system. The Addis Abeba Transportation Authority prioritizes client happiness by providing fair service. The company should have a system in place for managing time, resources, and people effectively. It should also provide employees the opportunity to contribute to client handling policies.

Keywords: customer satisfaction, transportation, services, determinants

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5219 A Study on the False Alarm Rates of MEWMA and MCUSUM Control Charts When the Parameters Are Estimated

Authors: Umar Farouk Abbas, Danjuma Mustapha, Hamisu Idi

Abstract:

It is now a known fact that quality is an important issue in manufacturing industries. A control chart is an integrated and powerful tool in statistical process control (SPC). The mean µ and standard deviation σ parameters are estimated. In general, the multivariate exponentially weighted moving average (MEWMA) and multivariate cumulative sum (MCUSUM) are used in the detection of small shifts in joint monitoring of several correlated variables; the charts used information from past data which makes them sensitive to small shifts. The aim of the paper is to compare the performance of Shewhart xbar, MEWMA, and MCUSUM control charts in terms of their false rates when parameters are estimated with autocorrelation. A simulation was conducted in R software to generate the average run length (ARL) values of each of the charts. After the analysis, the results show that a comparison of the false alarm rates of the charts shows that MEWMA chart has lower false alarm rates than the MCUSUM chart at various levels of parameter estimated to the number of ARL0 (in control) values. Also noticed was that the sample size has an advert effect on the false alarm of the control charts.

Keywords: average run length, MCUSUM chart, MEWMA chart, false alarm rate, parameter estimation, simulation

Procedia PDF Downloads 195