Search results for: loss distribution approach.
2775 Disaster Preparedness and Management in Saudi Arabia: An Empirical Investigation
Authors: Shougi Suliman Abosuliman, Arun Kumar, Firoz Alam
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Disaster preparedness is a key success factor for any effective disaster management practices. This paper evaluates the disaster preparedness and management in Saudi Arabia using an empirical investigation approach. It presents the results of the survey conducted by interviewing representatives of the Saudi decision-makers and administrators responsible for disaster control in Jeddah before, during and after flooding in 2009 and 2010. First, demographics of the respondents are presented, followed by quantitative analysis of their views and experiences regarding the Kingdom’s readiness before and after each flood. This is shown as a series of dependent and independent variables. Following this is a list of respondents’ priorities for disaster preparation in the Kingdom.
Keywords: Disaster response policy, crisis management, effective service delivery.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 67402774 Time-Delay Estimation Using Cross-ΨB-Energy Operator
Authors: Z. Saidi, A.O. Boudraa, J.C. Cexus, S. Bourennane
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In this paper, a new time-delay estimation technique based on the cross IB-energy operator [5] is introduced. This quadratic energy detector measures how much a signal is present in another one. The location of the peak of the energy operator, corresponding to the maximum of interaction between the two signals, is the estimate of the delay. The method is a fully data-driven approach. The discrete version of the continuous-time form of the cross IBenergy operator, for its implementation, is presented. The effectiveness of the proposed method is demonstrated on real underwater acoustic signals arriving from targets and the results compared to the cross-correlation method.Keywords: Teager-Kaiser energy operator, Cross-energyoperator, Time-Delay, Underwater acoustic signals.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 56492773 Stress Analysis of Hexagonal Element for Precast Concrete Pavements
Authors: J. Novak, A. Kohoutkova, V. Kristek, J. Vodicka, M. Sramek
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While the use of cast-in-place concrete for an airfield and highway pavement overlay is very common, the application of precast concrete elements is very limited today. The main reasons consist of high production costs and complex structural behavior. Despite that, several precast concrete systems have been developed and tested with the aim to provide a system with rapid construction. The contribution deals with the reinforcement design of a hexagonal element developed for a proposed airfield pavement system. The sub-base course of the system is composed of compacted recycled concrete aggregates and fiber reinforced concrete with recycled aggregates place on top of it. The selected element belongs to a group of precast concrete elements which are being considered for the construction of a surface course. Both high costs of full-scale experiments and the need to investigate various elements force to simulate their behavior in a numerical analysis software by using finite element method instead of performing expensive experiments. The simulation of the selected element was conducted on a nonlinear model in order to obtain such results which could fully compensate results from experiments. The main objective was to design reinforcement of the precast concrete element subject to quasi-static loading from airplanes with respect to geometrical imperfections, manufacturing imperfections, tensile stress in reinforcement, compressive stress in concrete and crack width. The obtained findings demonstrate that the position and the presence of imperfection in a pavement highly affect the stress distribution in the precast concrete element. The precast concrete element should be heavily reinforced to fulfill all the demands. Using under-reinforced concrete elements would lead to the formation of wide cracks and cracks permanently open.
Keywords: Imperfection, numerical simulation, pavement, precast concrete element, reinforcement design, stress analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7622772 Orthogonal Polynomial Density Estimates: Alternative Representation and Degree Selection
Authors: Serge B. Provost, Min Jiang
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The density estimates considered in this paper comprise a base density and an adjustment component consisting of a linear combination of orthogonal polynomials. It is shown that, in the context of density approximation, the coefficients of the linear combination can be determined either from a moment-matching technique or a weighted least-squares approach. A kernel representation of the corresponding density estimates is obtained. Additionally, two refinements of the Kronmal-Tarter stopping criterion are proposed for determining the degree of the polynomial adjustment. By way of illustration, the density estimation methodology advocated herein is applied to two data sets.Keywords: kernel density estimation, orthogonal polynomials, moment-based methodologies, density approximation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23702771 EUDIS-An Encryption Scheme for User-Data Security in Public Networks
Authors: S. Balaji, M. Rajaram
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The method of introducing the proxy interpretation for sending and receiving requests increase the capability of the server and our approach UDIV (User-Data Identity Security) to solve the data and user authentication without extending size of the data makes better than hybrid IDS (Intrusion Detection System). And at the same time all the security stages we have framed have to pass through less through that minimize the response time of the request. Even though an anomaly detected, before rejecting it the proxy extracts its identity to prevent it to enter into system. In case of false anomalies, the request will be reshaped and transformed into legitimate request for further response. Finally we are holding the normal and abnormal requests in two different queues with own priorities.
Keywords: IDS, Data & User authentication, UDIS.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18542770 Application of Adaptive Neuro-Fuzzy Inference System in Smoothing Transition Autoregressive Models
Authors: Ε. Giovanis
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In this paper we propose and examine an Adaptive Neuro-Fuzzy Inference System (ANFIS) in Smoothing Transition Autoregressive (STAR) modeling. Because STAR models follow fuzzy logic approach, in the non-linear part fuzzy rules can be incorporated or other training or computational methods can be applied as the error backpropagation algorithm instead to nonlinear squares. Furthermore, additional fuzzy membership functions can be examined, beside the logistic and exponential, like the triangle, Gaussian and Generalized Bell functions among others. We examine two macroeconomic variables of US economy, the inflation rate and the 6-monthly treasury bills interest rates.Keywords: Forecasting, Neuro-Fuzzy, Smoothing transition, Time-series
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16302769 Numerical Simulation of Deoilin Hydrocyclones
Authors: Reza Maddahian, Bijan Farhanieh, Simin Dokht Saemi
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In this research the separation efficiency of deoiling hydrocyclone is evaluated using three-dimensional simulation of multiphase flow based on Eulerian-Eulerian finite volume method. The mixture approach of Reynolds Stress Model is also employed to capture the features of turbulent multiphase swirling flow. The obtained separation efficiency of Colman's design is compared with available experimental data and showed that the separation curve of deoiling hydrocyclones can be predicted using numerical simulation.
Keywords: Deoiling hydrocyclone, Eulerian-Eulerian Model, Numerical simulation, Separation efficiency, Reynolds Stress Model
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28612768 Life Table and Reproductive Table Parameters of Scolothrips Longicornis (Thysanoptera: Thripidae) as a Predator of Two-Spotted Spider Mite, Tetranychus Turkestani (Acari: Tetranychidae)
Authors: Mehdi Gheibi, Shahram Hesami
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Scolothrips longicornis Priesner is one of the important predators of tetranychid mites with a wide distribution throughout Iran. Life table and population growth parameters of S. longicornis feeding on two-spotted spider mite, Tetranychus turkestani Ugarov & Nikolski were investigated under laboratory condition (26±1ºC, 65±5% R.H. and 16L: 8D). To carry of these experiments, S. longicornis collections reared on cowpea infested with T. turkestani were prepared. The eggs with less than 24 hours old were selected and reared. The emerged larvae feeding directly on cowpea leaf discs which were infested with T. turkestani. Thirty females of S. longicornis with 24 hours age were selected and released on infested leaf discs. They replaced daily to a new leaf disc and the laying eggs have counted. The experiment continued till the last thrips had died. The result showed that the mean age mortality of the adult female thrips were between 21-25 days which is nearly equal life expectancy (ex) at the time of adult eclosion. Parameters related to reproductive table including gross reproductive rate, net reproductive rate, intrinsic rate of natural increase and finite rate of increase were 48.91, 37.63, 0.26 and 2.3, respectively. Mean age per female/day, mean fertile egg per female/day, gross hatch rate, mean net age fertility, mean net age fecundity, net fertility rate and net fecundity rate were 2.23, 1.76, 0.87, 13.87, 14.26, 69.1 and 78.5, respectively. Sex ratio of offspring also recorded daily. The highest sex ratio for females was 0.88 in first day of oviposition. The sex ratio decreased gradually and reached under 0.46 after the day 26 and the oviposition rate declined. Then it seems that maintenance of rearing culture of predatory thrips for mass rearing later than 26 days after egg-laying commence is not profitable.Keywords: Tetranychus, Scolothrips, Demography, Life table, Reproductive table
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22242767 Co-Creational Model for Blended Learning in a Flipped Classroom Environment Focusing on the Combination of Coding and Drone-Building
Authors: A. Schuchter, M. Promegger
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The outbreak of the COVID-19 pandemic has shown us that online education is so much more than just a cool feature for teachers – it is an essential part of modern teaching. In online math teaching, it is common to use tools to share screens, compute and calculate mathematical examples, while the students can watch the process. On the other hand, flipped classroom models are on the rise, with their focus on how students can gather knowledge by watching videos and on the teacher’s use of technological tools for information transfer. This paper proposes a co-educational teaching approach for coding and engineering subjects with the help of drone-building to spark interest in technology and create a platform for knowledge transfer. The project combines aspects from mathematics (matrices, vectors, shaders, trigonometry), physics (force, pressure and rotation) and coding (computational thinking, block-based programming, JavaScript and Python) and makes use of collaborative-shared 3D Modeling with clara.io, where students create mathematics knowhow. The instructor follows a problem-based learning approach and encourages their students to find solutions in their own time and in their own way, which will help them develop new skills intuitively and boost logically structured thinking. The collaborative aspect of working in groups will help the students develop communication skills as well as structural and computational thinking. Students are not just listeners as in traditional classroom settings, but play an active part in creating content together by compiling a Handbook of Knowledge (called “open book”) with examples and solutions. Before students start calculating, they have to write down all their ideas and working steps in full sentences so other students can easily follow their train of thought. Therefore, students will learn to formulate goals, solve problems, and create a ready-to use product with the help of “reverse engineering”, cross-referencing and creative thinking. The work on drones gives the students the opportunity to create a real-life application with a practical purpose, while going through all stages of product development.Keywords: Flipped classroom, co-creational education, coding, making, drones, co-education, ARCS-model, problem-based learning.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5042766 A Ground Observation Based Climatology of Winter Fog: Study over the Indo-Gangetic Plains, India
Authors: Sanjay Kumar Srivastava, Anu Rani Sharma, Kamna Sachdeva
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Every year, fog formation over the Indo-Gangetic Plains (IGPs) of Indian region during the winter months of December and January is believed to create numerous hazards, inconvenience, and economic loss to the inhabitants of this densely populated region of Indian subcontinent. The aim of the paper is to analyze the spatial and temporal variability of winter fog over IGPs. Long term ground observations of visibility and other meteorological parameters (1971-2010) have been analyzed to understand the formation of fog phenomena and its relevance during the peak winter months of January and December over IGP of India. In order to examine the temporal variability, time series and trend analysis were carried out by using the Mann-Kendall Statistical test. Trend analysis performed by using the Mann-Kendall test, accepts the alternate hypothesis with 95% confidence level indicating that there exists a trend. Kendall tau’s statistics showed that there exists a positive correlation between time series and fog frequency. Further, the Theil and Sen’s median slope estimate showed that the magnitude of trend is positive. Magnitude is higher during January compared to December for the entire IGP except in December when it is high over the western IGP. Decade wise time series analysis revealed that there has been continuous increase in fog days. The net overall increase of 99 % was observed over IGP in last four decades. Diurnal variability and average daily persistence were computed by using descriptive statistical techniques. Geo-statistical analysis of fog was carried out to understand the spatial variability of fog. Geo-statistical analysis of fog revealed that IGP is a high fog prone zone with fog occurrence frequency of more than 66% days during the study period. Diurnal variability indicates the peak occurrence of fog is between 06:00 and 10:00 local time and average daily fog persistence extends to 5 to 7 hours during the peak winter season. The results would offer a new perspective to take proactive measures in reducing the irreparable damage that could be caused due to changing trends of fog.
Keywords: Fog, climatology, Mann-Kendall test, trend analysis, spatial variability, temporal variability, visibility.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17552765 Comparison of Developed Statokinesigram and Marker Data Signals by Model Approach
Authors: Boris Barbolyas, Kristina Buckova, Tomas Volensky, Cyril Belavy, Ladislav Dedik
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Background: Based on statokinezigram, the human balance control is often studied. Approach to human postural reaction analysis is based on a combination of stabilometry output signal with retroreflective marker data signal processing, analysis, and understanding, in this study. The study shows another original application of Method of Developed Statokinesigram Trajectory (MDST), too. Methods: In this study, the participants maintained quiet bipedal standing for 10 s on stabilometry platform. Consequently, bilateral vibration stimuli to Achilles tendons in 20 s interval was applied. Vibration stimuli caused that human postural system took the new pseudo-steady state. Vibration frequencies were 20, 60 and 80 Hz. Participant's body segments - head, shoulders, hips, knees, ankles and little fingers were marked by 12 retroreflective markers. Markers positions were scanned by six cameras system BTS SMART DX. Registration of their postural reaction lasted 60 s. Sampling frequency was 100 Hz. For measured data processing were used Method of Developed Statokinesigram Trajectory. Regression analysis of developed statokinesigram trajectory (DST) data and retroreflective marker developed trajectory (DMT) data were used to find out which marker trajectories most correlate with stabilometry platform output signals. Scaling coefficients (λ) between DST and DMT by linear regression analysis were evaluated, too. Results: Scaling coefficients for marker trajectories were identified for all body segments. Head markers trajectories reached maximal value and ankle markers trajectories had a minimal value of scaling coefficient. Hips, knees and ankles markers were approximately symmetrical in the meaning of scaling coefficient. Notable differences of scaling coefficient were detected in head and shoulders markers trajectories which were not symmetrical. The model of postural system behavior was identified by MDST. Conclusion: Value of scaling factor identifies which body segment is predisposed to postural instability. Hypothetically, if statokinesigram represents overall human postural system response to vibration stimuli, then markers data represented particular postural responses. It can be assumed that cumulative sum of particular marker postural responses is equal to statokinesigram.Keywords: Center of pressure (CoP), a method of developed statokinesigram trajectory (MDST), a model of postural system behavior, retroreflective marker data.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7622764 Improvement of Contractor’s Competitiveness through Sustainable Construction Practices in UAE
Authors: Sareh Rajabi, Taha Anjamrooz, Salwa Bheiry
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Sustainability of construction projects is an important issue to be addressed since the sector will continue to be developed in the coming years, especially in developing countries. Thus, it is significant to discover approaches and solutions for improving sustainability. Currently, the construction industry is the largest consumer of natural resources. This is the same in other countries in the Gulf region, and the United Arab Emirates (UAE) has limited natural resources such as water, electricity, etc. Recently, the UAE has taken several actions in order to implement sustainable initiatives within its construction industry. Within the industry, the contractors’ role is significant in promoting sustainable development by taking the responsibility to minimize their negative impacts on the environment and society, and maximize their economic distribution. In this research, sustainability will be studied as an important key to bring competitive advantages to contracting organizations. The contractors should understand the need to improve their sustainable performance in order to expand their business competitiveness. Competitiveness at the construction project level refers to a contractor’s ability to compete for a project. There is less focus on how to improve contractors’ competitiveness by implementing sustainable construction practices. Based on an inclusive literature review on the relationship between sustainability performance and business competitiveness, this research will conduct a study of sustainable practice in the construction industry and the relationship between sustainability performance and business competitiveness in order to develop a framework for evaluating how contractors can improve their competitiveness in terms of more efficient processes, enhancements in productivity, and lower costs of compliance in order to reduce the initial project cost and obtain market opportunities in the UAE. The research findings will provide a framework that can be a useful guideline for contractors to develop their sustainability policy, strategy and practice for meeting the increased requirements for sustainable development in construction.
Keywords: Sustainable construction practice, sustainability, competitiveness, construction industry, contractors.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11192763 Neural Network in Fixed Time for Collision Detection between Two Convex Polyhedra
Authors: M. Khouil, N. Saber, M. Mestari
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In this paper, a different architecture of a collision detection neural network (DCNN) is developed. This network, which has been particularly reviewed, has enabled us to solve with a new approach the problem of collision detection between two convex polyhedra in a fixed time (O (1) time). We used two types of neurons, linear and threshold logic, which simplified the actual implementation of all the networks proposed. The study of the collision detection is divided into two sections, the collision between a point and a polyhedron and then the collision between two convex polyhedra. The aim of this research is to determine through the AMAXNET network a mini maximum point in a fixed time, which allows us to detect the presence of a potential collision.
Keywords: Collision identification, fixed time, convex polyhedra, neural network, AMAXNET.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18162762 Effect of Environmental Parameters on the Water Solubility of the Polycyclic Aromatic Hydrocarbons and Derivatives Using Taguchi Experimental Design Methodology
Authors: P. Pimsee, C. Sablayrolles, P. de Caro, J. Guyomarch, N. Lesage, M. Montréjaud-Vignoles
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The MIGR’HYCAR research project was initiated to provide decisional tools for risks connected to oil spill drifts in continental waters. These tools aim to serve in the decision-making process once oil spill pollution occurs and/or as reference tools to study scenarios of potential impacts of pollutions on a given site. This paper focuses on the study of the distribution of polycyclic aromatic hydrocarbons (PAHs) and derivatives from oil spill in water as function of environmental parameters. Eight petroleum oils covering a representative range of commercially available products were tested. 41 polycyclic aromatic hydrocarbons (PAHs) and derivates, among them 16 EPA priority pollutants were studied by dynamic tests at laboratory scale. The chemical profile of the water soluble fraction was different from the parent oil profile due to the various water solubility of oil components. Semi-volatile compounds (naphtalenes) constitute the major part of the water soluble fraction. A large variation in composition of the water soluble fraction was highlighted depending on oil type. Moreover, four environmental parameters (temperature, suspended solid quantity, salinity and oil: water surface ratio) were investigated with the Taguchi experimental design methodology. The results showed that oils are divided into three groups: the solubility of Domestic fuel and Jet A1 presented a high sensitivity to parameters studied, meaning they must be taken into account. For Gasoline (SP95-E10) and Diesel fuel, a medium sensitivity to parameters was observed. In fact, the four others oils have shown low sensitivity to parameters studied. Finally, three parameters were found to be significant towards the water soluble fraction.
Keywords: Monitoring, PAHs, SBSE, water soluble fraction, Taguchi experimental design.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19742761 Assessment Tool for Social Responsibility Performance According to the ISO 26000
Authors: W. Fethallah, L. Chraibi, N. Sefiani
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The present paper is concerned with a statistical approach involving latent and manifest variables applied in order to assess the organization's social responsibility performance. The main idea is to develop an assessment tool and a measurement of the Social Responsibility Performance, enabling the company to characterize her performance regarding to the ISO 26000 standard's seven core subjects. For this, we conceptualize a structural equation modeling (SEM) which describes various causal connections between the Social Responsibility’s components. The SEM’s resolution is based on the Partial Least squares (PLS) method and the implementation is running in the XLSTAT software.Keywords: Corporate social responsibility, latent and manifest variable, partial least squares, structural equation model.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12252760 Image Search by Features of Sorted Gray level Histogram Polynomial Curve
Authors: Awais Adnan, Muhammad Ali, Amir Hanif Dar
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Image Searching was always a problem specially when these images are not properly managed or these are distributed over different locations. Currently different techniques are used for image search. On one end, more features of the image are captured and stored to get better results. Storing and management of such features is itself a time consuming job. While on the other extreme if fewer features are stored the accuracy rate is not satisfactory. Same image stored with different visual properties can further reduce the rate of accuracy. In this paper we present a new concept of using polynomials of sorted histogram of the image. This approach need less overhead and can cope with the difference in visual features of image.
Keywords: Sorted Histogram, Polynomial Curves, feature pointsof images, Grayscale, visual properties of image.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14282759 Design as Contract and Blueprint – Tackling Maturity Level 1 Software Vendors in an e-School Project
Authors: Yung-Pin Cheng, Ching-Huei Wang
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Process improvements have drawn much attention in practical software engineering. The capability maturity levels from CMMI have become an important index to assess a software company-s software engineering capability. However, in countries like Taiwan, customers often have no choices but to deal with vendors that are not CMMI prepared or qualified. We call these vendors maturitylevel- 1 (ML1) vendors. In this paper, we describe our experience from consulting an e-school project. We propose an approach to help our client tackle the ML1 vendors. Through our system analysis, we produce a design. This design is suggested to be used as part of contract and a blueprint to guide the implementation.Keywords: CMMI, Software Engineering, Software Design, Designas Contract.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15292758 An Improved GA to Address Integrated Formulation of Project Scheduling and Material Ordering with Discount Options
Authors: Babak H. Tabrizi, Seyed Farid Ghaderi
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Concurrent planning of the resource constraint project scheduling and material ordering problems have received significant attention within the last decades. Hence, the issue has been investigated here with the aim to minimize total project costs. Furthermore, the presented model considers different discount options in order to approach the real world conditions. The incorporated alternatives consist of all-unit and incremental discount strategies. On the other hand, a modified version of the genetic algorithm is applied in order to solve the model for larger sizes, in particular. Finally, the applicability and efficiency of the given model is tested by different numerical instances.Keywords: Genetic algorithm, material ordering, project management, project scheduling.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13022757 A Risk Management Approach for Nigeria Manufacturing Industries
Authors: Olaniyi O. Omoyajowo
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To be successful in today’s competitive global environment, manufacturing industry must be able to respond quickly to changes in technology. These changes in technology introduce new risks and hazards. The management of risk/hazard in a manufacturing process recommends method through which the success rate of an organization can be increased. Thus, there is a continual need for manufacturing industries to invest significant amount of resources in risk management, which in turn optimizes the production output and profitability of any manufacturing industry (if implemented properly). To help improve the existing risk prevention and mitigation practices in Small and Medium Enterprise (SME) in Nigeria Manufacturing Industries (NMI), the researcher embarks on this research to develop a systematic Risk Management process.
Keywords: Manufacturing industries, production output, risk, risk management, SMEs.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19392756 Fortification for P2P Grid Computing Used for Resource Discovery
Authors: Bhawneet Singh Marwah, Rishabh Rastogi, Shinon Kochar
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Grid computing provides an effective infrastructure for massive computation among flexible and dynamic collection of individual system for resource discovery. The major challenge for grid computing is to prevent breaches and secure the data from trespassers. To overcome such conflicts a semantic approach can be designed which will filter the access requests of peers by checking the resource description specifying the data and the metadata as factual statements. Between every node in the grid a semantic firewall as a middleware will be present The intruder will be required to present an application specifying there needs to the firewall and hence accordingly the system will grant or deny the application request.
Keywords: Grid Computing, Metadata, Semantic, Peers, Resource Discovery, Firewall.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15662755 Biomechanical Modeling, Simulation, and Comparison of Human Arm Motion to Mitigate Astronaut Task during Extra Vehicular Activity
Authors: B. Vadiraj, S. N. Omkar, B. Kapil Bharadwaj, Yash Vardhan Gupta
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During manned exploration of space, missions will require astronaut crewmembers to perform Extra Vehicular Activities (EVAs) for a variety of tasks. These EVAs take place after long periods of operations in space, and in and around unique vehicles, space structures and systems. Considering the remoteness and time spans in which these vehicles will operate, EVA system operations should utilize common worksites, tools and procedures as much as possible to increase the efficiency of training and proficiency in operations. All of the preparations need to be carried out based on studies of astronaut motions. Until now, development and training activities associated with the planned EVAs in Russian and U.S. space programs have relied almost exclusively on physical simulators. These experimental tests are expensive and time consuming. During the past few years a strong increase has been observed in the use of computer simulations due to the fast developments in computer hardware and simulation software. Based on this idea, an effort to develop a computational simulation system to model human dynamic motion for EVA is initiated. This study focuses on the simulation of an astronaut moving the orbital replaceable units into the worksites or removing them from the worksites. Our physics-based methodology helps fill the gap in quantitative analysis of astronaut EVA by providing a multisegment human arm model. Simulation work described in the study improves on the realism of previous efforts, incorporating joint stops to account for the physiological limits of range of motion. To demonstrate the utility of this approach human arm model is simulated virtually using ADAMS/LifeMOD® software. Kinematic mechanism for the astronaut’s task is studied from joint angles and torques. Simulation results obtained is validated with numerical simulation based on the principles of Newton-Euler method. Torques determined using mathematical model are compared among the subjects to know the grace and consistency of the task performed. We conclude that due to uncertain nature of exploration-class EVA, a virtual model developed using multibody dynamics approach offers significant advantages over traditional human modeling approaches.Keywords: Extra vehicular activity, biomechanics, inverse kinematics, human body modeling.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28432754 Calculation of Methane Emissions from Wetlands in Slovakia via IPCC Methodology
Authors: Jozef Mindas, Jana Skvareninova
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Wetlands are a main natural source of methane emissions, but they also represent the important biodiversity reservoirs in the landscape. There are about 26 thousands hectares of wetlands in Slovakia identified via the wetlands monitoring program. Created database of wetlands in Slovakia allows to analyze several ecological processes including also the methane emissions estimate. Based on the information from the database, the first estimate of the methane emissions from wetlands in Slovakia has been done. The IPCC methodology (Tier 1 approach) has been used with proposed emission factors for the ice-free period derived from the climatic data. The highest methane emissions of nearly 550 Gg are associated with the category of fens. Almost 11 Gg of methane is emitted from bogs, and emissions from flooded lands represent less than 8 Gg.Keywords: Methane emissions, wetlands, bogs, fens, Slovakia.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14132753 Concrete Gravity Dams and Traveling Wave Effect along Reservoir Bottom
Authors: H. Mirzabozorg, M. Varmazyari
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In the present article, effect of non-uniform excitation of reservoir bottom on nonlinear response of concrete gravity dams is considered. Anisotropic damage mechanics approach is used to model nonlinear behavior of mass concrete in 2D space. The tallest monolith of Pine Flat dam is selected as a case study. The horizontal and vertical components of 1967 Koyna earthquake is used to excite the system. It is found that crest response and stresses within the dam body decrease significantly when the reservoir is excited nonuniformly. In addition, the crack profiles within the dam body and in vicinity of the neck decreases.Keywords: Concrete gravity dam, dam-reservoir-foundation interaction, traveling wave, damage mechanics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18202752 Modeling Studies for Electrocoagulation
Authors: A. Genç, R. Hacıoğlu, B. Bakırcı
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Synthetic oily wastewaters were prepared from metal working fluids (MWF). Electrocoagulation experiments were performed under constant voltage application. The current, conductivity, pH, dissolved oxygen concentration and temperature were recorded on line at every 5 seconds during the experiments. Effects of applied voltage differences, electrode materials and distance between electrodes on removal efficiency have been investigated. According to the experimental results, the treatment of MWF wastewaters by iron electrodes rather than aluminum and stainless steel was much quicker; and the distance between electrodes should be less than 1cm. The electrocoagulation process was modeled by using block oriented approach and found out that it can be modeled as a single input and multiple output system. Modeling studies indicates that the electrocoagulation process has a nonlinear model structure.
Keywords: Electrocoagulation, oily wastewater, SIMO systems.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20872751 Kinetic Energy Recovery System Using Spring
Authors: Mayuresh Thombre, Prajyot Borkar, Mangirish Bhobe
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New advancement of technology and never satisfying demands of the civilization are putting huge pressure on the natural fuel resources and these resources are at a constant threat to its sustainability. To get the best out of the automobile, the optimum balance between performance and fuel economy is important. In the present state of art, either of the above two aspects are taken into mind while designing and development process which puts the other in the loss as increase in fuel economy leads to decrement in performance and vice-versa. In-depth observation of the vehicle dynamics apparently shows that large amount of energy is lost during braking and likewise large amount of fuel is consumed to reclaim the initial state, this leads to lower fuel efficiency to gain the same performance. Current use of Kinetic Energy Recovery System is only limited to sports vehicles only because of the higher cost of this system. They are also temporary in nature as power can be squeezed only during a small time duration and use of superior parts leads to high cost, which results on concentration on performance only and neglecting the fuel economy. In this paper Kinetic Energy Recovery System for storing the power and then using the same while accelerating has been discussed. The major storing element in this system is a Flat Spiral Spring that will store energy by compression and torsion.
The use of spring ensure the permanent storage of energy until used by the driver unlike present mechanical regeneration system in which the energy stored decreases with time and is eventually lost. A combination of internal gears and spur gears will be used in order to make the energy release uniform which will lead to safe usage. The system can be used to improve the fuel efficiency by assisting in overcoming the vehicle’s inertia after braking or to provide instant acceleration whenever required by the driver. The performance characteristics of the system including response time, mechanical efficiency and overall increase in efficiency are demonstrated. This technology makes the KERS (Kinetic Energy Recovery System) more flexible and economical allowing specific application while at the same time increasing the time frame and ease of usage.
Keywords: Electric control unit, Energy, Mechanical KERS, Planetary Gear system, Power, Smart braking, Spiral Spring.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 87902750 ERP Implementation Success in Iran: Examining the Role of System Environment Factors
Authors: Shahin Dezdar, Sulaiman Ainin
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The aim of this paper is to examine factors related to system environment (namely, system quality and vendor support) that influences ERP implementation success in Iranian companies. Implementation success is identified using user satisfaction and organizational impact perspective. The study adopts the survey questionnaire approach to collect empirical data. The questionnaire was distributed to ERP users and a total of 384 responses were used for analysis. The results illustrated that both system quality and vendor support have significant effect on ERP implementation success. This implies that companies must ensure they source for the best available system and a vendor that is dependable, reliable and trustworthy.
Keywords: Enterprise resource planning (ERP), Iran, system quality, vendor support.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29932749 Modeling and Simulation of Standalone Photovoltaic Charging Stations for Electric Vehicles
Authors: R. Mkahl, A. Nait-Sidi-Moh, M. Wack
Abstract:
Batteries of electric vehicles (BEV) are becoming more attractive with the advancement of new battery technologies and promotion of electric vehicles. BEV batteries are recharged on board vehicles using either the grid (G2V for Grid to Vehicle) or renewable energies in a stand-alone application (H2V for Home to Vehicle). This paper deals with the modeling, sizing and control of a photovoltaic stand-alone application that can charge the BEV at home. The modeling approach and developed mathematical models describing the system components are detailed. Simulation and experimental results are presented and commented.
Keywords: Electric vehicles, photovoltaic energy, lead-acid batteries, charging process, modeling, simulation, experimental tests.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 41992748 Salient Points Reduction for Content-Based Image Retrieval
Authors: Yao-Hong Tsai
Abstract:
Salient points are frequently used to represent local properties of the image in content-based image retrieval. In this paper, we present a reduction algorithm that extracts the local most salient points such that they not only give a satisfying representation of an image, but also make the image retrieval process efficiently. This algorithm recursively reduces the continuous point set by their corresponding saliency values under a top-down approach. The resulting salient points are evaluated with an image retrieval system using Hausdoff distance. In this experiment, it shows that our method is robust and the extracted salient points provide better retrieval performance comparing with other point detectors.Keywords: Barnard detector, Content-based image retrieval, Points reduction, Salient point.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14692747 Cosastudio: A Software Architecture Modeling Tool
Authors: Adel Smeda, Adel Alti, Mourad Oussalah, Abdallah Boukerram
Abstract:
A key aspect of the design of any software system is its architecture. An architecture description provides a formal model of the architecture in terms of components and connectors and how they are composed together. COSA (Component-Object based Software Structures), is based on object-oriented modeling and component-based modeling. The model improves the reusability by increasing extensibility, evolvability, and compositionality of the software systems. This paper presents the COSA modelling tool which help architects the possibility to verify the structural coherence of a given system and to validate its semantics with COSA approach.Keywords: Software Architecture, Architecture Description Languages, UML, Components, Connectors.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16812746 A Design for Application of Mobile Agent Technology to MicroService Architecture
Authors: Masayuki Higashino, Toshiya Kawato, Takao Kawamura
Abstract:
A monolithic service is based on the N-tier architecture in many cases. In order to divide a monolithic service into microservices, it is necessary to redefine a model as a new microservice by extracting and merging existing models across layers. Refactoring a monolithic service into microservices requires advanced technical capabilities, and it is a difficult way. This paper proposes a design and concept to ease the migration of a monolithic service to microservices using the mobile agent technology. Our proposed approach, mobile agents-based design and concept, enables to ease dividing and merging services.Keywords: Mobile agent, microservice, web service, distributed system.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1081