Search results for: financial performance
11477 [Keynote Talk]: sEMG Interface Design for Locomotion Identification
Authors: Rohit Gupta, Ravinder Agarwal
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Surface electromyographic (sEMG) signal has the potential to identify the human activities and intention. This potential is further exploited to control the artificial limbs using the sEMG signal from residual limbs of amputees. The paper deals with the development of multichannel cost efficient sEMG signal interface for research application, along with evaluation of proposed class dependent statistical approach of the feature selection method. The sEMG signal acquisition interface was developed using ADS1298 of Texas Instruments, which is a front-end interface integrated circuit for ECG application. Further, the sEMG signal is recorded from two lower limb muscles for three locomotions namely: Plane Walk (PW), Stair Ascending (SA), Stair Descending (SD). A class dependent statistical approach is proposed for feature selection and also its performance is compared with 12 preexisting feature vectors. To make the study more extensive, performance of five different types of classifiers are compared. The outcome of the current piece of work proves the suitability of the proposed feature selection algorithm for locomotion recognition, as compared to other existing feature vectors. The SVM Classifier is found as the outperformed classifier among compared classifiers with an average recognition accuracy of 97.40%. Feature vector selection emerges as the most dominant factor affecting the classification performance as it holds 51.51% of the total variance in classification accuracy. The results demonstrate the potentials of the developed sEMG signal acquisition interface along with the proposed feature selection algorithm.Keywords: classifiers, feature selection, locomotion, sEMG
Procedia PDF Downloads 29611476 A Review of Physiological Measures for Cognitive Workload Assessment of Aircrew
Authors: Naveed Tahir, Adnan Maqsood
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Cognitive workload is a significant factor affecting user performance, and it has been broadly investigated for its application in ergonomics as well as in designing and optimizing effective human-machine interactions. It is mentally challenging to maneuver an aircraft, and pilots must control the aircraft and adequately communicate to the verbal-auditory stimuli. Several physiological measures have long been researched and used to demonstrate the cognitive workload. In our current study, we have summarized recent findings of the effectiveness, accuracy, and applicability of commonly used physiological measures in evaluating cognitive workload. We have also highlighted on the advancements in physiological measures. The strength and limitations of physiological measures have also been discussed to assess the cognitive workload of people, especially the aircrews in laboratory settings and real-time situations. We have presented the research findings of the physiological measures to base suggestions on the proper applications of the measures and settings demanding the use of single measure or their combinations.Keywords: aircrew, cognitive workload, subjective measure, physiological measure, performance measure
Procedia PDF Downloads 16511475 Investigation of Multiple Dynamic Vibration Absorbers' Performance in Overhead Transmission Lines
Authors: Pedro F. D. Oliveira, Rangel S. Maia, Aline S. Paula
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As the electric energy consumption grows, the necessity of energy transmission lines increases. One of the problems caused by an oscillatory response to dynamical loads (such as wind effects) in transmission lines is the cable fatigue. Thus, the dynamical behavior of transmission cables understanding and its control is extremely important. The socioeconomic damage caused by a failure in these cables can be quite significant, from large economic losses to energy supply interruption in large regions. Dynamic Vibration Absorbers (DVA) are oscillatory elements used to mitigate the vibration of a primary system subjected to harmonic excitation. The positioning of Stockbridge (DVA for overhead transmission lines) plays an important role in mitigating oscillations of transmission lines caused by airflows. Nowadays, the positioning is defined by technical standards or commercial software. The aim of this paper is to conduct an analysis of multiple DVAs performances in cable conductors of overhead transmission lines. The cable is analyzed by a finite element method and the model is calibrated by experimental results. DVAs performance is analyzed by evaluating total cable energy, and a study of multiple DVAs positioning is conducted. The results are compared to the existing regulations showing situations where proper positioning, different from the standard, can lead to better performance of the DVA. Results also show situations where the use of multiple DVAs is appropriate.Keywords: dynamical vibration absorber, finite element method, overhead transmission lines, structural dynamics
Procedia PDF Downloads 12911474 Carbon Dioxide Hydrogenation to Methanol over Cu/ZnO-SBA-15 Catalyst: Effect of Metal Loading
Authors: S. F. H. Tasfy, N. A. M. Zabidi, M.-S. Shaharun
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Utilization of CO2 as a carbon source to produce valuable chemicals is one of the important ways to reduce the global warming caused by increasing CO2 in the atmosphere. Supported metal catalysts are crucial for the production of clean and renewable fuels and chemicals from the stable CO2 molecules. The catalytic conversion of CO2 into methanol is recently under increased scrutiny as an opportunity to be used as a low-cost carbon source. Therefore, series of the bimetallic Cu/ZnO-based catalyst supported by SBA-15 were synthesized via impregnation technique with different total metal loading and tested in the catalytic hydrogenation of CO2 to methanol. The morphological and textural properties of the synthesized catalysts were determined by transmission electron microscopy (TEM), temperature programmed desorption, reduction, oxidation and pulse chemisorption (TPDRO), and N2-adsorption. The CO2 hydrogenation reaction was performed in microactivity fixed-bed system at 250 °C, 2.25 MPa, and H2/CO2 ratio of 3. Experimental results showed that the catalytic structure and performance was strongly affected by the loading of the active site. Where, the catalytic activity, methanol selectivity as well as the space-time yield increased with increasing the metal loading until it reaches the maximum values at a metal loading of 15 wt% while further addition of metal inhibits the catalytic performance. The higher catalytic activity of 14 % and methanol selectivity of 92 % were obtained over Cu/ZnO-SBA-15 catalyst with total bimetallic loading of 15 wt%. The excellent performance of 15 wt% Cu/ZnO-SBA-15 catalyst is attributed to the presence of well disperses active sites with small particle size, higher Cu surface area, and lower catalytic reducibility.Keywords: hydrogenation of carbon dioxide, methanol synthesis, metal loading, Cu/ZnO-SBA-15 catalyst
Procedia PDF Downloads 23211473 Developing Performance Model for Road Side Elements Receiving Periodic Maintenance
Authors: Ayman M. Othman, Hassan Y. Ahmed, Tallat A. Ali
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Inadequate maintenance programs and funds allocated for highway networks in the developed countries have led to fast deterioration of road side elements. Therefore, this research focuses on developing a performance model for road side elements periodic maintenance activities. Road side elements that receive periodic maintenance include; earthen shoulder, road signs and traffic markings. Using the level of service concept, the developed model can determine the optimal periodic maintenance intervals for those elements based on a selected level of service suitable with the available periodic maintenance budget. Data related to time periods for progressive deterioration stages for the chosen elements were collected. Ten maintenance experts in Aswan, Sohag and Assiut cities were interviewed for that purpose. Time in months related to 10%, 25%, 40%, 50%, 75%, 90% and 100% deterioration of each road side element was estimated based on the experts opinion. Least square regression analysis has shown that a power function represents the best fit for earthen shoulders edge drop-off and damage of road signs with time. It was also evident that, the progressive dirtiness of road signs could be represented by a quadratic function an a linear function could represent the paint degradation nature of both traffic markings and road signs. Actual measurements of earthen shoulder edge drop-off agree considerably with the developed model.Keywords: deterioration, level of service, periodic maintenance, performance model, road side element
Procedia PDF Downloads 57511472 Study of the Performance of Metal Tanks with a Floating Roof
Authors: Rezki Akkouche
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This work exposes metal tanks in general and floating roofs in particular by listing the codes and standards which study this kind of structure. Initial research discusses the types of tanks, how they are designed, and the disadvantages and advantages that each type has. Then, in-depth research was carried out carefully in order to popularize the floating roof tank and the principles of its design and operation while defining the different types of this kind of roof, how and what they are designed, naming the main installation accessories for these roofs and the dangers that a malfunction of these accessories would cause, also exposing the problems likely to be encountered on these roofs and the considerable and important advantages that floating roof tanks bring. A simplification of the two API 650 and Eurocode 3 regulations - Tanks part - has been made by explaining and mentioning the design rules and laws of this type of structure. Thus a comparison of the two regulations is accomplished by exemplifying this with a study of an actual project.Keywords: tanks of metal, floating roof, performance, comparative analysis
Procedia PDF Downloads 13111471 Gaussian Particle Flow Bernoulli Filter for Single Target Tracking
Authors: Hyeongbok Kim, Lingling Zhao, Xiaohong Su, Junjie Wang
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The Bernoulli filter is a precise Bayesian filter for single target tracking based on the random finite set theory. The standard Bernoulli filter often underestimates the number of targets. This study proposes a Gaussian particle flow (GPF) Bernoulli filter employing particle flow to migrate particles from prior to posterior positions to improve the performance of the standard Bernoulli filter. By employing the particle flow filter, the computational speed of the Bernoulli filters is significantly improved. In addition, the GPF Bernoulli filter provides a more accurate estimation compared with that of the standard Bernoulli filter. Simulation results confirm the improved tracking performance and computational speed in two- and three-dimensional scenarios compared with other algorithms.Keywords: Bernoulli filter, particle filter, particle flow filter, random finite sets, target tracking
Procedia PDF Downloads 9411470 A Review on Various Approaches for Energy Conservation in Green Cloud Computing
Authors: Sumati Manchanda
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Cloud computing is one of the most recent developing engineering and is consistently utilized as a part of different IT firms so as to make benefits like expense sparing or financial minimization, it must be eco cordial also. In this manner, Green Cloud Computing is the need of the today's current situation. It is an innovation that is rising as data correspondence engineering. This paper surveys the unequivocal endeavors made by different specialists to make Cloud Computing more vitality preserving, to break down its vitality utilization focused around sorts of administrations gave furthermore to diminish the carbon foot shaped impression rate by colossal methodologies furthermore edify virtualization idea alongside different diverse methodologies which utilize virtual machines scheduling and migration. The summary of the proposed work by various authors that we have reviewed is also presented in the paper.Keywords: cloud computing, green cloud computing, scheduling, migration, virtualization, energy efficiency
Procedia PDF Downloads 39511469 Multi-Level Framework for Effective Use of Stock Ordering System: Case Study of Small Enterprises in Kgautswane
Authors: Lethamaga Tladi, Ray Kekwaletswe
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This study sought to conceptualise a multi-level framework for the effective use of stock ordering system in small enterprises in a rural area context. The interpretive research methodology has been used to enable the researcher to analyse, in-depth, and the subjective meanings of small enterprises’ employees in using the stock ordering system. The empirical data was collected from 13 small enterprises’ employees as participants through semi-structured interviews and observations. Interpretive Phenomenological Analysis (IPA) approach was used to analyse the small enterprises’ employee’s own account of lived experiences in relations to stock ordering system use in terms of their relatedness to, and cognitive engagement with. A case study of Kgautswane, a rural area in Limpopo Province, South Africa, served as a social context where the phenomenon manifested. Technology-Organisation-Environment Theory (TOE), Technology-to-Performance Chain Model (TPC), and Representation Theory (RT) underpinned this study. In this multi-level study, the findings revealed that; At the organisational level, the effective use of stock ordering system was found to be associated with the organisational performance gains such as efficiency, productivity, quality, competitiveness, and market share. Equally so, at the individual level, the effective use of stock ordering system minimised the end-user’s efforts and time to accomplish their tasks, which yields improved individual performance. The Multi-level framework for effective use of stock ordering system was presented.Keywords: effective use, multi-dimensions of use, multi-level of use, multi-level research, small enterprises, stock ordering system
Procedia PDF Downloads 17211468 Wear Resistance and Mechanical Performance of Ultra-High Molecular Weight Polyethylene Influenced by Temperature Change
Authors: Juan Carlos Baena, Zhongxiao Peng
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Ultra-high molecular weight polyethylene (UHMWPE) is extensively used in industrial and biomedical fields. The slippery nature of UHMWPE makes this material suitable for surface bearing applications, however, the operational conditions limit the lubrication efficiency, inducing boundary and mixed lubrication in the tribological system. The lack of lubrication in a tribological system intensifies friction, contact stress and consequently, operating temperature. With temperature increase, the material’s mechanical properties are affected, and the lifespan of the component is reduced. The understanding of how mechanical properties and wear performance of UHMWPE change when the temperature is increased has not been clearly identified. The understanding of the wear and mechanical performance of UHMWPE at different temperature is important to predict and further improve the lifespan of these components. This study evaluates the effects of temperature variation in a range of 20 °C to 60 °C on the hardness and the wear resistance of UHMWPE. A reduction of the hardness and wear resistance was observed with the increase in temperature. The variation of the wear rate increased 94.8% when the temperature changed from 20 °C to 50 °C. Although hardness is regarded to be an indicator of the material wear resistance, this study found that wear resistance decreased more rapidly than hardness with the temperature increase, evidencing a low material stability of this component in a short temperature interval. The reduction of the hardness was reflected by the plastic deformation and abrasion intensity, resulting in a significant wear rate increase.Keywords: hardness, surface bearing, tribological system, UHMWPE, wear
Procedia PDF Downloads 27411467 Seismic Retrofit of Reinforced Concrete Structures by Highly Dissipative Technologies
Authors: Stefano Sorace, Gloria Terenzi, Giulia Mazzieri, Iacopo Costoli
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The prolonged earthquake sequence that struck several urban agglomerations and villages in Central Italy, starting from 24 August 2016 through January 2017, highlighted once again the seismic vulnerability of pre-normative reinforced concrete (R/C) structures. At the same time, considerable damages were surveyed in recently retrofitted R/C buildings too, one of which also by means of a dissipative bracing system. The solution adopted for the latter did not expressly take into account the performance of non-structural elements, and namely of infills and partitions, confirming the importance of their dynamic interaction with the structural skeleton. Based on this consideration, an alternative supplemental damping-based retrofit solution for this representative building, i.e., a school with an R/C structure situated in the municipality of Norcia, is examined in this paper. It consists of the incorporation of dissipative braces equipped with pressurized silicone fluid viscous (FV) dampers, instead of the BRAD system installed in the building, the delayed activation of which -caused by the high stiffness of the constituting metallic dampers- determined the observed non-structural damages. Indeed, the alternative solution proposed herein, characterized by dissipaters with mainly damping mechanical properties, guarantees an earlier activation of the protective system. A careful assessment analysis, preliminarily carried out to simulate and check the case study building performance in originally BRAD-retrofitted conditions, confirms that the interstorey drift demand related to the Norcia earthquake's mainshock and aftershocks is beyond the response capacity of infills. The verification analyses developed on the R/C structure, including the FV-damped braces, highlight their higher performance, giving rise to a completely undamaged response both of structural and non-structural elements up to the basic design earthquake normative level of seismic action.Keywords: dissipative technologies, performance assessment analysis, concrete structures, seismic retrofit
Procedia PDF Downloads 13711466 Whistleblowing a Contemporary Topic Concerning Businesses
Authors: Andreas Kapardis, Maria Krambia-Kapardis, Sofia Michaelides-Mateou
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Corruption and economic crime is a serious problem affecting the sustainability of businesses in the 21st century. Nowadays, many corruption or fraud cases come to light thanks to whistleblowers. This article will first discuss the concept of whistleblowing as well as some relevant legislation enacted around the world. Secondly, it will discuss the findings of a survey of whistleblowers or could-have-been whistleblowers. Finally, suggestions for the development of a comprehensive whistleblowing framework will be considered. Whistleblowing can be described as expressing a concern about a wrongdoing within an organization, such as a corporation, an association, an institution or a union. Such concern must be in the public interest and in good faith and should relate to the cover up of matters that could potentially result in a miscarriage of justice, a crime, criminal offence and threats to health and safety. Whistleblowing has proven to be an effective anti-corruption mechanism and a powerful tool that helps deterring fraud, violations, and malpractices within organizations, corporations and the public sector. Research in the field of whistleblowing has concentrated on the reasons for whistleblowing and financial bounties; the effectiveness of whistleblowing; whistleblowing being a prosocial behavior with a psychological perspective and consequences; as a tool in protecting shareholders, saving lives and billions of dollars of public funds. Whilst, no other study of whistleblowing has been carried out on whistleblowers or intended whistleblowers. The study reported in the current paper analyses the findings of 74 whistleblowers or intended whistleblowers, the reasons behind their decision to blow the whistle, or not to proceed to blow the whistle and any regrets they may have had. In addition a profile of a whistleblower is developed concerning their age, gender, marital and family status and position in an organization. Lessons learned from the intended whistleblowers and in response to the questions if they would be willing to blow the whistle again show that enacting legislation to protect the whistleblower is not enough. Similarly, rewarding the whistleblower does not appear to provide the whistleblower with an incentive since the majority noted that “work ethics is more important than financial rewards”. We recommend the development of a comprehensive and holistic framework for the protection of the whistleblower and to ensure that remedial actions are immediately taken once a whistleblower comes forward. The suggested framework comprises (a) hard legislation in ensuring the whistleblowers follow certain principles when blowing the whistle and, in return, are protected for a period of 5 years from being fired, dismissed, bullied, harassed; (b) soft legislation in establishing an agency to firstly ensure psychological and legal advice is provided to the whistleblowers and secondly any required remedial action is immediately taken to avert the undesirable events reported by a whistleblower from occurring and, finally; (c) mechanisms to ensure the coordination of actions taken.Keywords: whistleblowing, business ethics, legislation, business
Procedia PDF Downloads 31111465 Mapping and Mitigation Strategy for Flash Flood Hazards: A Case Study of Bishoftu City
Authors: Berhanu Keno Terfa
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Flash floods are among the most dangerous natural disasters that pose a significant threat to human existence. They occur frequently and can cause extensive damage to homes, infrastructure, and ecosystems while also claiming lives. Although flash floods can happen anywhere in the world, their impact is particularly severe in developing countries due to limited financial resources, inadequate drainage systems, substandard housing options, lack of early warning systems, and insufficient preparedness. To address these challenges, a comprehensive study has been undertaken to analyze and map flood inundation using Geographic Information System (GIS) techniques by considering various factors that contribute to flash flood resilience and developing effective mitigation strategies. Key factors considered in the analysis include slope, drainage density, elevation, Curve Number, rainfall patterns, land-use/cover classes, and soil data. These variables were computed using ArcGIS software platforms, and data from the Sentinel-2 satellite image (with a 10-meter resolution) were utilized for land-use/cover classification. Additionally, slope, elevation, and drainage density data were generated from the 12.5-meter resolution of the ALOS Palsar DEM, while other relevant data were obtained from the Ethiopian Meteorological Institute. By integrating and regularizing the collected data through GIS and employing the analytic hierarchy process (AHP) technique, the study successfully delineated flash flood hazard zones (FFHs) and generated a suitable land map for urban agriculture. The FFH model identified four levels of risk in Bishoftu City: very high (2106.4 ha), high (10464.4 ha), moderate (1444.44 ha), and low (0.52 ha), accounting for 15.02%, 74.7%, 10.1%, and 0.004% of the total area, respectively. The results underscore the vulnerability of many residential areas in Bishoftu City, particularly the central areas that have been previously developed. Accurate spatial representation of flood-prone areas and potential agricultural zones is crucial for designing effective flood mitigation and agricultural production plans. The findings of this study emphasize the importance of flood risk mapping in raising public awareness, demonstrating vulnerability, strengthening financial resilience, protecting the environment, and informing policy decisions. Given the susceptibility of Bishoftu City to flash floods, it is recommended that the municipality prioritize urban agriculture adaptation, proper settlement planning, and drainage network design.Keywords: remote sensing, flush flood hazards, Bishoftu, GIS.
Procedia PDF Downloads 3911464 Factors Influencing the Adoption of Interpersonal Communication Media to Maximize Business Competitiveness among Small and Medium Enterprises in Hong Kong: Industry Types and Entrepreneur Characteristics
Authors: Olivine Lo
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Small- and Medium-Sized Enterprises (SMEs) consist of a broad variety of businesses, ranging from small grocery shops to manufacturing concerns. Some are dynamic and innovative, while others are more traditional. The definition of SMEs varies by country but is most determined by the number of employees, though business assets and sales revenues are alternative measures. There are eight main types of SME industries in Hong Kong: garment, electronics, plastics, metal and machinery, trading and logistics, building, manufacturing, and service industries. Information exchange is a key goal of human communication, and communicators have used a variety of media to maintain relationships through traditional face-to-face interactions and written forms like letters and faxes. With the advancement of mediated-interpersonal communication media from telephone to synchronic online tools like email, instant messaging, voice messaging, and video conferencing for sustaining relationships, particularly enabling geographically distanced relationships. Although these synchronous tools are gaining popularity, they are facilitating relationship maintenance in everyday life and complementing rather than replacing the more conventional face-to-face interactions. This study will test if there are any variances in effects by industry type among Hong Kong SMEs. The competitiveness of the business environment refers to the competition faced by a business within its particular industry. The more intense the competition in a given sector, the greater the potential for strategic uses of specific needs in a business. Both internal organization characteristics and external environments may affect firm performance and financial resources. The level of competitiveness within an industry will be a more reliable indicator to show how Hong Kong SMEs are striving to achieve their business goals using different techniques in their communication media preferences, rather than mere classification by industry type. This study thus divides the competitiveness of the business environment into internal and external: (1) the internal environment competition is the inherent competitiveness of the products or services provided by the SMEs, whereas (2) the external environment competition includes the economic and political realities and competitors joining the market. This study will test various organizational characteristics and competitiveness of the business environment to predict entrepreneurs’ communication media preferences.Keywords: competitiveness of business environment, small- and medium-sized enterprises, organizational characteristics, communication media preference
Procedia PDF Downloads 3411463 Multivariate Analysis of Spectroscopic Data for Agriculture Applications
Authors: Asmaa M. Hussein, Amr Wassal, Ahmed Farouk Al-Sadek, A. F. Abd El-Rahman
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In this study, a multivariate analysis of potato spectroscopic data was presented to detect the presence of brown rot disease or not. Near-Infrared (NIR) spectroscopy (1,350-2,500 nm) combined with multivariate analysis was used as a rapid, non-destructive technique for the detection of brown rot disease in potatoes. Spectral measurements were performed in 565 samples, which were chosen randomly at the infection place in the potato slice. In this study, 254 infected and 311 uninfected (brown rot-free) samples were analyzed using different advanced statistical analysis techniques. The discrimination performance of different multivariate analysis techniques, including classification, pre-processing, and dimension reduction, were compared. Applying a random forest algorithm classifier with different pre-processing techniques to raw spectra had the best performance as the total classification accuracy of 98.7% was achieved in discriminating infected potatoes from control.Keywords: Brown rot disease, NIR spectroscopy, potato, random forest
Procedia PDF Downloads 19211462 Performance of Bimetallic Catalyst in the Oxidation of Volatile Organic Compounds
Authors: Faezeh Aghazadeh
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The catalytic activity of Pt/γ-Al₂O₃ and Pt-Fe/γ-Al₂O₃ catalysts was investigated to bring about the complete oxidation of 2-Propanol. Among them, Pt-Fe/γ-Al₂O₃ was found to be the most promising catalyst based on activity. The catalysts were characterized by (XRD), (SEM), (TEM) and ICP-AES techniques. Iron loadings on Pt/γ-Al₂O₃ had a great effect on catalytic activity, and Pt-Fe/γ-Al₂O₃ (1.75 wt% Fe) catalyst at calcination temperature 300°C was observed to be the most active, which might be contributed to the favorable synergetic effects between Pt and Fe, high activity and the well-dispersed bimetallic phase. The combustion of 2-Propanol in the vapor phase was carried out in a conventional flow U-shape glass reactor used in the differential mode at atmospheric pressure. 2-Propanol was analyzed by a gas chromatograph VARIAN 3800 CX equipped with an FID. As observed, better performance and activity were observed for Pt-Fe/Al₂O₃ bimetallic catalyst. These results indicate that the high dispersion on support gives a positive effect on catalytic activity.Keywords: volatile organic compounds, bimetallic catalyst, catalytic activity, low temperature
Procedia PDF Downloads 15011461 Analyzing the Empirical Link between Islamic Finance and Growth of Real Output: A Time Series Application to Pakistan
Authors: Nazima Ellahi, Danish Ramzan
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There is a growing trend among development economists regarding the importance of financial sector for economic development and growth activities. The development thus introduced, helps to promote welfare effects and poverty alleviation. This study is an attempt to find the nature of link between Islamic banking financing and development of output growth for Pakistan. Time series data set has been utilized for a time period ranging from 1990 to 2010. Following the Phillip Perron (PP) and Augmented Dicky Fuller (ADF) test of unit root this study applied Ordinary Least Squares (OLS) method of estimation and found encouraging results in favor of promoting the Islamic banking practices in Pakistan.Keywords: Islamic finance, poverty alleviation, economic growth, finance, commerce
Procedia PDF Downloads 34811460 Bulk Electrical Resistivity of Geopolymer Mortars: The Effect of Binder Composition and Alkali Concentration
Authors: Mahdi Babaee, Arnaud Castel
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One of the main hurdles for commercial adaptation of geopolymer concrete (GPC) as a low-embodied-carbon alternative for Portland cement concrete (PCC) is the durability aspects and its long-term performance in aggressive/corrosive environments. GPC is comparatively a new engineering material and in the absence of a track record of successful durability performance, proper experimental studies to investigate different durability-related characteristics of GPC seem inevitable. In this context, this paper aims to study the bulk electrical resistivity of geopolymer mortars fabricated of blends of low-calcium fly ash (FA) and ground granulated blast-furnace slag (GGBS). Bulk electrical resistivity is recognized as one of the most important parameters influencing the rate of corrosion of reinforcing bars during the propagation phase of corrosion. To investigate the effect of alkali concentration on the resistivity of the samples, 100x200 mm mortar cylinders were cast at different alkali concentration levels, whereas the modulus ratio (the molar ratio of SiO2/Na2O) was fixed for the mixes, and the bulk electrical resistivity was then measured. Also, the effect of the binder composition was assessed with respect to the ratio of FA to GGBS used. Results show a superior performance of samples with higher GGBS content. Lower concentration of the solution has increased the resistivity by reducing the amount of mobile alkali ions in the pore solution. Moreover, GGBS-based samples showed a much sharper increase in the electrical resistivity with decreasing the moisture content.Keywords: bulk resistivity, corrosion, durability, geopolymer concrete
Procedia PDF Downloads 26811459 The Quality Assurance on the Standard of Private Schools in Bangkok
Authors: Autjira Songjan, Poramatdha Chutimant
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This research is intended to study the operational quality assurance of private schools in Bangkok according to the opinions of administrators and teachers. Second is comparing the opinions of administrators and teachers about operating quality assurance process by gender, job and work experience. The sample include administrators and teachers of private schools in the Education School in Bangkok by using a proportion random technic. The questionnaire are used as query operations quality assurance to collect the data of private schools, the statistics that are used to analyze the data using the percentage, mean, standard deviation and Test the difference value and test of variance. The research found that the administrators and teachers have different sex, positions and duties have the different opinions about quality assurance in different statistically insignificant level 0.05 in the elements of performance management and the quality of the service that provided to students in the school.Keywords: educational quality assurance, performance management, private schools in Bangkok, quality of the service
Procedia PDF Downloads 23311458 Lignin Phenol Formaldehyde Resole Resin: Synthesis and Characteristics
Authors: Masoumeh Ghorbania, Falk Liebnerb, Hendrikus W.G. van Herwijnenc, Johannes Konnertha
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Phenol formaldehyde (PF) resins are widely used as wood adhesives for variety of industrial products such as plywood, laminated veneer lumber and others. Lignin as a main constituent of wood has become well-known as a potential substitute for phenol in PF adhesives because of their structural similarity. During the last decades numerous research approaches have been carried out to substitute phenol with pulping-derived lignin, whereby the lower reactivity of resins synthesized with shares of lignin seem to be one of the major challenges. This work reports about a systematic screening of different types of lignin (plant origin and pulping process) for their suitability to replace phenol in phenolic resins. Lignin from different plant sources (softwood, hardwood and grass) were used, as these should differ significantly in their reactivity towards formaldehyde of their reactive phenolic core units. Additionally a possible influence of the pulping process was addressed by using the different types of lignin from soda, kraft, and organosolv process and various lignosulfonates (sodium, ammonium, calcium, magnesium). To determine the influence of lignin on the adhesive performance beside others the rate of viscosity development, bond strength development of varying hot pressing time and other thermal properties were investigated. To evaluate the performance of the cured end product, a few selected properties were studied at the example of solid wood-adhesive bond joints, compact panels and plywood. As main results it was found that lignin significantly accelerates the viscosity development in adhesive synthesis. Bonding strength development during curing of adhesives decelerated for all lignin types, while this trend was least for pine kraft lignin and spruce sodium lignosulfonate. However, the overall performance of the products prepared with the latter adhesives was able to fulfill main standard requirements, even after exposing the products to harsh environmental conditions. Thus, a potential application can be considered for processes where reactivity is less critical but adhesive cost and product performance is essential.Keywords: phenol formaldehyde resin, lignin phenol formaldehyde resin, ABES, DSC
Procedia PDF Downloads 23811457 Comparison Between PID and PD Controllers for 4 Cable-Based Robots
Authors: Fouad Inel, Lakhdar Khochemane
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This article presents a comparative response specification performance between two controllers of three and four cable based robots for various applications. The main objective of this work is: the first is to use the direct and inverse geometric model to study and simulate the end effector position of the robot with three and four cables. A graphical user interface has been implemented in order to visualizing the position of the robot. Secondly, we present the determination of static and dynamic tensions and lengths of cables required to flow different trajectories. At the end, we study the response of our systems in closed loop with a Proportional-IntegratedDerivative (PID) and Proportional-Integrated (PD) controllers then this last are compared the results of the same examples using MATLAB/Simulink; we found that the PID method gives the better performance, such as rapidly speed response, settling time, compared to PD controller.Keywords: dynamic modeling, geometric modeling, graphical user interface, open loop, parallel cable-based robots, PID/PD controllers
Procedia PDF Downloads 42511456 Development of Children through the Prism of Pending Bills in India: An Analytical Study
Authors: S. Sunaina, Neha Saini
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Children are considered as future of a country. In order to have a better future, better laws are required in the present, especially for the children. Their development primarily revolves around physical, mental, psychological, emotional and financial facets. Hence the holistic development of a child in the contemporary society is a must in order to secure a better future. The present paper is an endeavour to analyse the development of children in India vis-a-vis The Child Development Bill 2016 and Child Labour (Abolition) Bill 2016 pending before the Indian Parliament. The findings of the study will attempt to highlight the flaws of the Bills and their probable repercussions, supporting the same with Constitutional provisions, judicial precedents, and the international perspective. Finally, the paper will conclude with concrete suggestions to overcome the flaws of the Bills so that the Bills, when passed, can be sincerely implemented.Keywords: bill, children, development, repercussion
Procedia PDF Downloads 27311455 Aerodynamic Heating and Drag Reduction of Pegasus-XL Satellite Launch Vehicle
Authors: Syed Muhammad Awais Tahir, Syed Hossein Raza Hamdani
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In the last two years, there has been a substantial increase in the rate of satellite launches. To keep up with the technology, it is imperative that the launch cost must be made affordable, especially in developing and underdeveloped countries. Launch cost is directly affected by the launch vehicle’s aerodynamic performance. Pegasus-XL SLV (Satellite Launch Vehicle) has been serving as a commercial SLV for the last 26 years, commencing its commercial flight operation from the six operational sites all around the US and Europe, and the Marshal Islands. Aerodynamic heating and drag contribute largely to Pegasus’s flight performance. The objective of this study is to reduce the aerodynamic heating and drag on Pegasus’s body significantly for supersonic and hypersonic flight regimes. Aerodynamic data for Pegasus’s first flight has been validated through CFD (Computational Fluid Dynamics), and then drag and aerodynamic heating is reduced by using a combination of a forward-facing cylindrical spike and a conical aero-disk at the actual operational flight conditions. CFD analysis using ANSYS fluent will be carried out for Mach no. ranges from 0.83 to 7.8, and AoA (Angle of Attack) ranges from -4 to +24 degrees for both simple and spiked-configuration, and then the comparison will be drawn using a variety of graphs and contours. Expected drag reduction for supersonic flight is to be around 15% to 25%, and for hypersonic flight is to be around 30% to 50%, especially for AoA < 15⁰. A 5% to 10% reduction in aerodynamic heating is expected to be achieved for hypersonic regions. In conclusion, the aerodynamic performance of air-launched Pegasus-XL SLV can be further enhanced, leading to its optimal fuel usage to achieve a more economical orbital flight.Keywords: aerodynamics, pegasus-XL, drag reduction, aerodynamic heating, satellite launch vehicle, SLV, spike, aero-disk
Procedia PDF Downloads 11211454 Family Succession and Cost of Bank Loans: Evidence from China
Authors: Tzu-Ching Weng, Hsin-Yi Chi
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This study examines the effect of family succession on the cost of bank loans and non-price contractual terms. We use a unique dataset from China and find that lending banks are likely to charge high-interest rates and offer tight contractual terms, such as loan maturity and collateral requirement, for family succession firms. These findings indicate that information and default risks may arise after subsequent family successions. We also find that family succession firms can reduce the cost of bank loans by hiring top-tier auditors to enhance financial reporting credibility. This finding suggests that professional and high-quality auditors can provide extremely valuable services to family succession firms.Keywords: family succession, cost of bank loans, loan contract terms, top-tier auditor
Procedia PDF Downloads 8811453 Generative Adversarial Network Based Fingerprint Anti-Spoofing Limitations
Authors: Yehjune Heo
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Fingerprint Anti-Spoofing approaches have been actively developed and applied in real-world applications. One of the main problems for Fingerprint Anti-Spoofing is not robust to unseen samples, especially in real-world scenarios. A possible solution will be to generate artificial, but realistic fingerprint samples and use them for training in order to achieve good generalization. This paper contains experimental and comparative results with currently popular GAN based methods and uses realistic synthesis of fingerprints in training in order to increase the performance. Among various GAN models, the most popular StyleGAN is used for the experiments. The CNN models were first trained with the dataset that did not contain generated fake images and the accuracy along with the mean average error rate were recorded. Then, the fake generated images (fake images of live fingerprints and fake images of spoof fingerprints) were each combined with the original images (real images of live fingerprints and real images of spoof fingerprints), and various CNN models were trained. The best performances for each CNN model, trained with the dataset of generated fake images and each time the accuracy and the mean average error rate, were recorded. We observe that current GAN based approaches need significant improvements for the Anti-Spoofing performance, although the overall quality of the synthesized fingerprints seems to be reasonable. We include the analysis of this performance degradation, especially with a small number of samples. In addition, we suggest several approaches towards improved generalization with a small number of samples, by focusing on what GAN based approaches should learn and should not learn.Keywords: anti-spoofing, CNN, fingerprint recognition, GAN
Procedia PDF Downloads 18711452 An Overview on Micro Irrigation-Accelerating Growth of Indian Agriculture
Authors: Rohit Lall
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The adoption of Micro Irrigation (MI) technologies in India has helped in achieving higher cropping and irrigation intensity with significant savings on resource savings such as labour, fertilizer and improved crop yields. These technologies have received considerable attention from policymakers, growers and researchers over the years for its perceived ability to contribute towards agricultural productivity and economic growth with the well-being of the growers of the country. Keeping the pace with untapped theoretical potential to cover government had launched flagship programs/centre sector schemes with earmarked budget to capture the potential under these waters saving techniques envisaged under these technologies by way of providing financial assistance to the beneficiaries for adopting these technologies. Micro Irrigation technologies have been in the special attention of the policymakers over the years. India being an agrarian economy having engaged 75% of the population directly or indirectly having skilled, semi-skilled and entrepreneurs in the sector with focused attention and financial allocations from the government under these technologies in covering the untapped potential under Pradhan Mantri Krishi Sinchayee Yojana (PMKSY) 'Per Drop More Crop component.' During the year 2004, a Taskforce on Micro Irrigation was constituted to estimate the potential of these technologies in India which was estimated 69.5 million hectares by the Task Force Report on MI however only 10.49 million hectares have been achieved so far. Technology collaborations by leading manufacturing companies in overseas have proved to a stepping stone in technology advancement and product up gradation with increased efficiencies. Joint ventures by the leading MI companies have added huge business volumes which have not only accelerated the momentum of achieving the desired goal but in terms of area coverage but had also generated opportunities for the polymer manufacturers in the country. To provide products matching the global standards Bureau of Indian Standards have constituted a sectional technical committee under the Food and Agriculture Department (FAD)-17 to formulated/devise and revise standards pertaining to MI technologies. The research lobby has also contributed at large by developing in-situ analysis proving MI technologies a boon for farming community of the country with resource conservation of which water is of paramount importance. Thus, Micro Irrigation technologies have proved to be the key tool for feeding the grueling demand of food basket of the growing population besides maintaining soil health and have been contributing towards doubling of farmers’ income.Keywords: task force on MI, standards, per drop more crop, doubling farmers’ income
Procedia PDF Downloads 12011451 Effectiveness of Natural Zeolite in Mitigating Alkali Silica Reaction Expansions
Authors: Esma Gizem Daskiran, Mehmet Mustafa Daskiran
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This paper investigates the effectiveness of two natural zeolites in reducing expansion of concrete due to alkali-silica reaction. These natural zeolites have different reactive silica content. Three aggregates; two natural sand and one crushed stone aggregate were used while preparing mortar bars in accordance with accelerated mortar bar test method, ASTM C1260. Performance of natural zeolites are compared by examining the expansions due to alkali silica reaction. Natural zeolites added to the mixtures at %10 and %20 replacement levels by weight of cement. Natural zeolite with high reactive silica content had better performance on reducing expansions due to ASR. In this research, using high reactive zeolite at %20 replacement level was effective in mitigating expansions.Keywords: alkali silica reaction, natural zeolite, durability, expansion
Procedia PDF Downloads 39411450 Amine Hardeners with Carbon Nanotubes Dispersing Ability for Epoxy Coating Systems
Authors: Szymon Kugler, Krzysztof Kowalczyk, Tadeusz Spychaj
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An addition of carbon nanotubes (CNT) can simultaneously improve many features of epoxy coatings, i.e. electrical, mechanical, functional and thermal. Unfortunately, this nanofiller negatively affects visual properties of the coatings, such as transparency and gloss. The main reason for the low visual performance of CNT-modified epoxy coatings is the lack of compatibility between CNT and popular amine curing agents, although epoxy resins based on bisphenol A are indisputable good CNT dispersants. This is a serious obstacle in utilization of the coatings in advanced applications, demanding both high transparency and electrical conductivity. The aim of performed investigations was to find amine curing agents exhibiting affinity for CNT, and ensuring good performance of epoxy coatings with them. Commercially available CNT was dispersed in epoxy resin, as well as in different aliphatic, cycloaliphatic and aromatic amines, using one of two dispergation methods: ultrasonic or mechanical. The CNT dispersions were subsequently used in the preparation of epoxy coating compositions and coatings on a transparent substrate. It was found that amine derivative of bio-based cardanol, as well as modified o-tolylbiguanide exhibit significant CNT, dispersing properties, resulting in improved transparent/electroconductive performance of epoxy coatings. In one of prepared coating systems just 0.025 wt.% (250 ppm) of CNT was enough to obtain coatings with semi conductive properties, 83% of transparency as well as perfect chemical resistance to methyl-ethyl ketone and improved thermal stability. Additionally, a theory of the influence of amine chemical structure on CNT dispersing properties was proposed.Keywords: bio-based cardanol, carbon nanotubes, epoxy coatings, tolylbiguanide
Procedia PDF Downloads 21311449 Airport Investment Risk Assessment under Uncertainty
Authors: Elena M. Capitanul, Carlos A. Nunes Cosenza, Walid El Moudani, Felix Mora Camino
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The construction of a new airport or the extension of an existing one requires massive investments and many times public private partnerships were considered in order to make feasible such projects. One characteristic of these projects is uncertainty with respect to financial and environmental impacts on the medium to long term. Another one is the multistage nature of these types of projects. While many airport development projects have been a success, some others have turned into a nightmare for their promoters. This communication puts forward a new approach for airport investment risk assessment. The approach takes explicitly into account the degree of uncertainty in activity levels prediction and proposes milestones for the different stages of the project for minimizing risk. Uncertainty is represented through fuzzy dual theory and risk management is performed using dynamic programming. An illustration of the proposed approach is provided.Keywords: airports, fuzzy logic, risk, uncertainty
Procedia PDF Downloads 41511448 Educators’ Adherence to Learning Theories and Their Perceptions on the Advantages and Disadvantages of E-Learning
Authors: Samson T. Obafemi, Seraphin D. Eyono-Obono
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Information and Communication Technologies (ICTs) are pervasive nowadays, including in education where they are expected to improve the performance of learners. However, the hope placed in ICTs to find viable solutions to the problem of poor academic performance in schools in the developing world has not yet yielded the expected benefits. This problem serves as a motivation to this study whose aim is to examine the perceptions of educators on the advantages and disadvantages of e-learning. This aim will be subdivided into two types of research objectives. Objectives on the identification and design of theories and models will be achieved using content analysis and literature review. However, the objective on the empirical testing of such theories and models will be achieved through the survey of educators from different schools in the Pinetown District of the South African Kwazulu-Natal province. SPSS is used to quantitatively analyse the data collected by the questionnaire of this survey using descriptive statistics and Pearson correlations after assessing the validity and the reliability of the data. The main hypothesis driving this study is that there is a relationship between the demographics of educators’ and their adherence to learning theories on one side, and their perceptions on the advantages and disadvantages of e-learning on the other side, as argued by existing research; but this research views these learning theories under three perspectives: educators’ adherence to self-regulated learning, to constructivism, and to progressivism. This hypothesis was fully confirmed by the empirical study except for the demographic factor where teachers’ level of education was found to be the only demographic factor affecting the perceptions of educators on the advantages and disadvantages of e-learning.Keywords: academic performance, e-learning, learning theories, teaching and learning
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