Search results for: safety instrumented function
5037 Influence of Coenzyme as a Corrosion Barrier for Biodegradable Magnesium
Authors: Minjung Park, Jimin Park, Youngwoon Kim, Hyungseop Han, Myoungryul Ok, Hojeong Jeon, Hyunkwang Seok, Yuchan Kim
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Magnesium is an essential element in human body and has unique characteristics such as bioabsorbable and biodegradable properties. Therefore, there has been much attention on studies on the implants based on magnesium to avoid subsequent surgery. However, high amount of hydrogen gas is generated by relatively severe corrosion of magnesium especially in aqueous condition with chloride ions. And it contributes to the causes of swelling of skin and causes consequent inflammation of soft tissue where is directly in contact with implants. Therefore, there is still concern about the safety of the using biodegradable magnesium alloys, which is limited to various applications. In this study, we analyzed the influence of coenzyme on corrosion behavior of magnesium. The analysis of corrosion rate was held by using Hanks’ balanced salt solution (HBSS) as a body stimulated fluid and in condition of 37°C. Thus, with deferring the concentration of the coenzyme used in this study, corrosion rates from 0.0654ml/ cm² to 0.0438ml/cm² were observed in immersion tests. Also, comparable results were obtained in electrochemical tests. Results showed that hydrogen gas produced from corrosion of magnesium can be controlled.Keywords: biodegradable magnesium, biomaterials, coenzyme, corrosion
Procedia PDF Downloads 4275036 Model Studies on Use of Coal Mine Waste and Modified Clay Soil as Fill Material for Embankments and Foundations
Authors: K. Suresh, M. Padmavathi, N. Darga Kumar
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The objective of this study is to investigate the significance of coal mine waste and improved clay soil when used as a fill and for the construction of embankment. To determine the bearing capacities of coal mine waste and improved clay soil, tests are conducted apart from laboratory experiments. PLAXIS 2D software is used to make the analysis simpler. Depending upon the bearing capacities obtained for different cases, a conclusion can be drawn. Load carrying capacities are determined for coal mine waste, clay and by altering their height ratio when clay (H2) is at the bottom, and coal mine waste (H1) is on the top with three different cases (H = 0.25H1 + 0.75H2, 0.5H1 + 0.5H2, 0.75H1 + 0.25H2) in addition to this bearing capacity of improved clay soil (by replacing clay with 10% CMW, 30% CMW and 50% CMW in addition polycom) is also determined. The safe height of the embankment that can be constructed with the improved clay for different slopes, i.e., for 1:1, 1.5: 1, 2: 1 is also determined by using PLAXIS 2D software by limiting the factor of safety to 1.5.Keywords: cohesion, angle of shearing resistance, elastic modulus, coefficient of consolidation, coal mine waste
Procedia PDF Downloads 245035 Seismic Performance of Reinforced Concrete Frame Structure Based on Plastic Rotation
Authors: Kahil Amar, Meziani Faroudja, Khelil Nacim
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The principal objective of this study is the evaluation of the seismic performance of reinforced concrete frame structures, taking into account of the behavior laws, reflecting the real behavior of materials, using CASTEM2000 software. A finite element model used is based in modified Takeda model with Timoshenko elements for columns and beams. This model is validated on a Vecchio experimental reinforced concrete (RC) frame model. Then, a study focused on the behavior of a RC frame with three-level and three-story in order to visualize the positioning the plastic hinge (plastic rotation), determined from the curvature distribution along the elements. The results obtained show that the beams of the 1st and 2nd level developed a very large plastic rotations, or these rotations exceed the values corresponding to CP (Collapse prevention with cp qCP = 0.02 rad), against those developed at the 3rd level, are between IO and LS (Immediate occupancy and life Safety with qIO = 0.005 rad and rad qLS = 0.01 respectively), so the beams of first and second levels submit a very significant damage.Keywords: seismic performance, performance level, pushover analysis, plastic rotation, plastic hinge
Procedia PDF Downloads 1335034 Investigation about Structural and Optical Properties of Bulk and Thin Film of 1H-CaAlSi by Density Functional Method
Authors: M. Babaeipour, M. Vejdanihemmat
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Optical properties of bulk and thin film of 1H-CaAlSi for two directions (1,0,0) and (0,0,1) were studied. The calculations are carried out by Density Functional Theory (DFT) method using full potential. GGA approximation was used to calculate exchange-correlation energy. The calculations are performed by WIEN2k package. The results showed that the absorption edge is shifted backward 0.82eV in the thin film than the bulk for both directions. The static values of the real part of dielectric function for four cases were obtained. The static values of the refractive index for four cases are calculated too. The reflectivity graphs have shown an intensive difference between the reflectivity of the thin film and the bulk in the ultraviolet region.Keywords: 1H-CaAlSi, absorption, bulk, optical, thin film
Procedia PDF Downloads 5245033 Phenomenon of Raveling Distress on the Flexible Pavements: An Overview
Authors: Syed Ali Shahbaz Shah
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In the last few years, Bituminous Asphaltic roads are becoming popular day by day in the world. Plenty of research has been carried out to identify many advantages like safety, environmental effects, and comfort. Some other benefits are minimal noise and skid resistance enhancement. Besides the benefits of asphaltic roads, the permeable structure of the road also causes some distress, and raveling is one of the crucial defects. The main reason behind this distress is the failure of adhesion between bitumen mortar, specifically due to excessive load from heavy traffic. The main focus of this study is to identify the root cause and propose both the long-term and the short-term solutions of raveling on a specific road section depicting the overall road situation from the bridge of Kahuta road towards the intersection of the Islamabad express highway. The methodology adopted for this purpose is visual inspections in-situ. It was noted that there were chunks of debris on the road surface, which indicates that the asphalt binder is aged the most probably. Further laboratory testing would confirm that either asphalt binder is aged or inadequate compaction was adept during cold weather paving.Keywords: asphaltic roads, asphalt binder, distress, raveling
Procedia PDF Downloads 1205032 Corporate Profitability through Effective Supply Chain Performance
Authors: Tareq N. Issa
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The main pressuring challenges of global competition and high returns have forced businesses to shift their strategic competitive advantage from physical distribution management to integrated logistics management, finally moving into supply chain management. Conventionally, corporate profitability is a function of cost, capital employed, revenue and customer service. This article gives an insight into the effect of supply chain management on each of the above variables. It investigates the impact of the changing levels/ effects of these variables on corporate profitability and the means of measuring supply chain financial effectiveness. Information technology tools form the basis for supply chain optimal performance through alignment of supply chain systems in this ever increasing complexity in business decisions.Keywords: corporate profitability, sypply chain systems, business decisions, competitive advanage
Procedia PDF Downloads 3405031 Implicit Off-Grid Block Method for Solving Fourth and Fifth Order Ordinary Differential Equations Directly
Authors: Olusola Ezekiel Abolarin, Gift E. Noah
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This research work considered an innovative procedure to numerically approximate higher-order Initial value problems (IVP) of ordinary differential equations (ODE) using the Legendre polynomial as the basis function. The proposed method is a half-step, self-starting Block integrator employed to approximate fourth and fifth order IVPs without reduction to lower order. The method was developed through a collocation and interpolation approach. The basic properties of the method, such as convergence, consistency and stability, were well investigated. Several test problems were considered, and the results compared favorably with both exact solutions and other existing methods.Keywords: initial value problem, ordinary differential equation, implicit off-grid block method, collocation, interpolation
Procedia PDF Downloads 895030 A Watermarking Signature Scheme with Hidden Watermarks and Constraint Functions in the Symmetric Key Setting
Authors: Yanmin Zhao, Siu Ming Yiu
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To claim the ownership for an executable program is a non-trivial task. An emerging direction is to add a watermark to the program such that the watermarked program preserves the original program’s functionality and removing the watermark would heavily destroy the functionality of the watermarked program. In this paper, the first watermarking signature scheme with the watermark and the constraint function hidden in the symmetric key setting is constructed. The scheme uses well-known techniques of lattice trapdoors and a lattice evaluation. The watermarking signature scheme is unforgeable under the Short Integer Solution (SIS) assumption and satisfies other security requirements such as the unremovability security property.Keywords: short integer solution (SIS) problem, symmetric-key setting, watermarking schemes, watermarked signatures
Procedia PDF Downloads 1375029 Need for Eye Care Services, Clinical Characteristics, Surgical Outcome and Prognostic Predictors of Cataract in Adult Participants with Intellectual Disability
Authors: Yun-Shan Tsai, Si-Ping Lin, En-Chieh Lin, Xin-Hong Chen, Shin-Yun Ho, Shin-Hong Huang, Ching-ju Hsieh
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Background and significance: Uncorrected refractive errors and cataracts are the main visually debilitating ophthalmological abnormalities in adult participants with intellectual disability (ID). However, not all adult participants with ID may receive a regular and timely ophthalmological assessment. Consequently, some of the ocular diseases may not be diagnosed until late, thereby causing unnecessary ocular morbidity. In addition, recent clinical practice and researches have also suggested that eye-care services for this group are neglected. Purpose: To investigate the unmet need for eye care services, clinical characteristics of cataract, visual function, surgical outcome and prognostic predictors in adult participants with ID at Taipei City Hospital in Taiwan. Methods: This is a one-year prospective clinical study. We recruited about 120 eyes of 60 adult participants with ID who were received cataract surgery. Caregivers of all participants received a questionnaire on current eye care services. Clinical demographic data, such as age, gender, and associated systemic diseases or syndromes, were collected. All complete ophthalmologic examinations were performed 1 month preoperatively and 3 months postoperatively, including ocular biometry, visual function, refractive status, morphology of cataract, associated ocular features, anesthesia methods, surgical types, and complications. Morphology of cataract, visual and surgical outcome was analyzed. Results: A total of 60 participants with mean age 43.66 ± 13.94 years, including 59.02% male and 40.98% female, took part in comprehensive eye-care services. The prevalence of unmet need for eye care services was high (about 70%). About 50% of adult participants with ID have bilateral cataracts at the time of diagnosis. White cataracts were noted in about 30% of all adult participants with ID at the time of presentation. Associated ocular disorders were included myopic maculopathy (4.54%), corneal disorders (11.36%), nystagmus (20.45%), strabismus (38.64%) and glaucoma (2.27%). About 26.7% of adult participants with ID underwent extracapsular cataract extraction whereas a phacoemulsification was performed in 100% of eyes. Intraocular lens implantation was performed in all eyes. The most common postoperative complication was posterior capsular opacification (30%). The mean best-corrected visual acuity was significantly improved from preoperatively (mean log MAR 0.48 ± 0.22) to at 3 months postoperatively (mean log MAR 0.045 ± 0.22) (p < .05). Conclusions: Regular follow up will help address the need for eye-care services in participants with ID. A high incidence of bilateral cataracts, as well as white cataracts, was observed in adult participants with ID. Because of early diagnosis and early intervention of cataract, the visual and surgical outcomes of cataract are good, but the visual outcomes are suboptimal due to associated ocular comorbidities.Keywords: adult participants with intellectual disability, cataract, cataract surgery
Procedia PDF Downloads 3155028 A Nutrient Formulation Affects Brain Myelination in Infants: An Investigative Randomized Controlled Trial
Authors: N. Schneider, M. Bruchhage, M. Hartweg, G. Mutungi, J. O Regan, S. Deoni
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Observational neuroimaging studies suggest differences between breast-fed and formula-fed infants in developmental myelination, a key brain process for learning and cognitive development. However, the possible effects of a nutrient formulation on myelin development in healthy term infants in an intervention study have not been investigated. Objective was, therefore, to investigate the efficacy of a nutrient formulation with higher levels of myelin-relevant nutrients as compared to a control formulation with lower levels of the same nutrients on brain myelination and cognitive development in the first 6 months of life. The study is an ongoing randomized, controlled, double-blind, two-center, parallel-group clinical trial with a nonrandomized, non-blinded arm of exclusively breastfed infants. The current findings result from a staged statistical analysis at 6 months; the recruitment and intervention period has been completed for all participants. Follow-up visits at 12, 18 and 24 months are still ongoing. N= 81 enrolled full term, neurotypical infants of both sexes were randomized into either the investigational (N= 42) or the control group (N= 39), and N= 108 children in the breast-fed arm served as a natural reference group. The effect of a blend of docosahexaenoic acid, arachidonic acid, iron, vitamin B12, folic acid as well as sphingomyelin from a uniquely proceed whey protein concentrate enriched in alpha-lactalbumin and phospholipids in an infant nutrition product matrix was investigated. The main outcomes for the staged statistical analyses at 6 months included brain myelination measures derived from MRI. Additional outcomes were brain volume, cognitive development and safety. The full analyses set at 6 months comprised N= 66 infants. Higher levels of myelin-relevant nutrients compared to lower levels resulted in significant differences in myelin structure, volume, and rate of myelination as early as 3 and 6 months of life. The cross-sectional change of means between groups for whole-brain myelin volume was 8.4% for investigational versus control formulation (3.5% versus the breastfeeding reference) group at 3 months and increased to 36.4% for investigational versus control formulation (14.1% versus breastfeeding reference) at 6 months. No statistically significant differences were detected for early cognition scores. Safety findings were largely similar across groups. This is the first pediatric nutritional neuroimaging study demonstrating the efficacy of a myelin nutrient blend on developmental myelination in well-nourished term infants. Myelination is a critical process in learning and development. The effects were demonstrated across the brain, particularly in temporal and parietal regions, known to be functionally involved in sensory, motor and language skills. These first results add to the field of nutritional neuroscience by demonstrating early life nutrition benefits for brain architecture which may be foundational for later cognitive and behavioral outcomes. ClinicalTrials.gov Identifier: NCT03111927 (Infant Nutrition and Brain Development - Full-Text View - ClinicalTrials.gov).Keywords: brain development, infant nutrition, MRI, myelination
Procedia PDF Downloads 2025027 The Role of Personality Type as Predictor of Trust among Ridesharing Community: Study in Nebengers Community Jakarta
Authors: Firdaus Amri, Ima Sri Rahmani
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Traffic jam becomes the main problem among the people in a metropolitan city, especially in Indonesia. Nebengers, as one of ridesharing community in Indonesia, offer solutions against this problem. Nebengers is a social media community that connect people who want to give the ride and who want to ask for the ride. But in reality, Nebengers still have quite problems, especially regarding the safety issue. Practically, in this issue, they (people in Nebengers) only depend on trust between the one who gives the ride and who asks for the ride. Trust is defined as an expectation that partners, including potential partners, have goodwill and benign intent in their dealing with one and another. This paper will examine the role of personality type as predictor of trust among Nebengers community. Hexaco Personality consists of six dimensions (honesty-humility, emotionality, agreeableness, conscientiousness, extraversion, and openness to experience) is used in this research. By using snowball sampling, we took 250 respondents from Nebengers community as participants for this research. They complete questionnaires which are provided in online form. The role of each personality type as a basic analysis to understand trust among Nebengers community will be discussed in this research.Keywords: Nebengers, personality type, ridesharing, trust
Procedia PDF Downloads 3625026 The Effect of the Proportion of Carbon on the Corrosion Rate of Carbon-Steel
Authors: Abdulmagid A. Khattabi, Ahmed A. Hablous, Mofied M. Elnemry
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The carbon steel is of one of the most common mineral materials used in engineering and industrial applications in order to have access to the required mechanical properties, especially after the change of carbon ratio, but this may lead to stimulate corrosion. It has been used in models of solids with different carbon ratios such as 0.05% C, 0.2% C, 0.35% C, 0.5% C, and 0.65% C and have been studied using three testing durations which are 4 weeks, 6 weeks, and 8 weeks and among different corrosion environments such as atmosphere, fresh water, and salt water. This research is for the purpose of finding the effect of the carbon content on the corrosion resistance of steels in different corrosion medium by using the weight loss technique as a function of the corrosion resistance. The results that have been obtained through this research shows that a correlation can be made between corrosion rates and steel's carbon content, and the corrosion resistance decreases with the increase in carbon content.Keywords: proportion of carbon in the steel, corrosion rate, erosion, corrosion resistance in carbon-steel
Procedia PDF Downloads 6085025 Prospects for Building Mobile Micro-Hydro Powerplants with Information Management Systems
Authors: B. S. Akhmetov, P. T.Kharitonov, L. Sh. Balgabayeva, O. V. Kisseleva, T. S. Kartbayev
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This article analyzes the applicability of known renewable energy technical means as mobile power sources under the field and extreme conditions. The requirements are determined for the parameters of mobile micro-HPP. The application prospectively of the mobile micro-HPP with intelligent control systems is proved for this purpose. Variants of low-speed electric generators for micro HPP are given. Variants of designs for mobile micro HPP are presented with the direct (gearless) transfer of torque from the hydraulic drive to the rotor of the electric generator. Variant of the hydraulic drive for micro HPP is described workable at low water flows. A general structure of the micro HPP intelligent system control is offered that implements the principle of maximum energy efficiency. The legitimacy of construction and application of mobile micro HPP is proved as electrical power sources for life safety of people under the field and extreme conditions.Keywords: mobile micro-hydro powerplants, information management systems, hydraulic drive, computer science
Procedia PDF Downloads 4135024 Beyond the Travel: The Impact of Public Transport on Quality of Life
Authors: Shadab Bahreini
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Public transportation is one of the most important aspects of cities, which impacts various factors of the Quality of Life (QoL) of citizens. A passenger's experience is influenced by a variety of indicators in addition to the cost and safety of the trip. This article intends to investigate how QoL is affected by public transport in an urban environment by introducing a literature review of QoL and Quality of Urban Life (QoUL), investigating the intersection of QoL and public transport, and reviewing the background theory for Transport Quality of Life (TQoL). The article proposes a Public Transport Quality of Life (PTQoL) framework comprised of a set of indicators that measure how public transport impacts QoL across personal (physical and mental), socioeconomic, and environmental dimensions. The study proposes using the framework to evaluate objective or subjective factors affecting a person's QoL regarding public transport. Finally, it concludes that public transport is a key component in shaping QoL in urban environments and that policymakers and urban planners should use the PTQoL framework to make evidence-based decisions to improve public transport systems and their impact on QoL.Keywords: public transport, quality of life, subjective and objective indicators, urban environment
Procedia PDF Downloads 1565023 Some Results for F-Minimal Hypersurfaces in Manifolds with Density
Authors: M. Abdelmalek
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In this work, we study the hypersurfaces of constant weighted mean curvature embedded in weighted manifolds. We give a condition about these hypersurfaces to be minimal. This condition is given by the ellipticity of the weighted Newton transformations. We especially prove that two compact hypersurfaces of constant weighted mean curvature embedded in space forms and with the intersection in at least a point of the boundary must be transverse. The method is based on the calculus of the matrix of the second fundamental form in a boundary point and then the matrix associated with the Newton transformations. By equality, we find the weighted elementary symmetric function on the boundary of the hypersurface. We give in the end some examples and applications. Especially in Euclidean space, we use the above result to prove the Alexandrov spherical caps conjecture for the weighted case.Keywords: weighted mean curvature, weighted manifolds, ellipticity, Newton transformations
Procedia PDF Downloads 995022 Mutual Authentication for Sensor-to-Sensor Communications in IoT Infrastructure
Authors: Shadi Janbabaei, Hossein Gharaee Garakani, Naser Mohammadzadeh
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Internet of things is a new concept that its emergence has caused ubiquity of sensors in human life, so that at any time, all data are collected, processed and transmitted by these sensors. In order to establish a secure connection, the first challenge is authentication between sensors. However, this challenge also requires some features so that the authentication is done properly. Anonymity, untraceability, and being lightweight are among the issues that need to be considered. In this paper, we have evaluated the authentication protocols and have analyzed the security vulnerabilities found in them. Then an improved light weight authentication protocol for sensor-to-sensor communications is presented which uses the hash function and logical operators. The analysis of protocol shows that security requirements have been met and the protocol is resistant against various attacks. In the end, by decreasing the number of computational cost functions, it is argued that the protocol is lighter than before.Keywords: anonymity, authentication, Internet of Things, lightweight, un-traceability
Procedia PDF Downloads 2975021 Applying Theory of Self-Efficacy in Intelligent Transportation Systems by Potential Usage of Vehicle as a Sensor
Authors: Aby Nesan Raj, Sumil K. Raj, Sumesh Jayan
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The objective of the study is to formulate a self-regulation model that shall enhance the usage of Intelligent Transportation Systems by understanding the theory of self-efficacy. The core logic of the self-regulation model shall monitor driver's behavior based on the situations related to the various sources of Self Efficacy like enactive mastery, vicarious experience, verbal persuasion and physiological arousal in addition to the vehicle data. For this study, four different vehicle data, speed, drowsiness, diagnostic data and surround camera views are considered. This data shall be given to the self-regulation model for evaluation. The oddness, which is the output of self-regulation model, shall feed to Intelligent Transportation Systems where appropriate actions are being taken. These actions include warning to the user as well as the input to the related transportation systems. It is also observed that the usage of vehicle as a sensor reduces the wastage of resource utilization or duplication. Altogether, this approach enhances the intelligence of the transportation systems especially in safety, productivity and environmental performance.Keywords: emergency management, intelligent transportation system, self-efficacy, traffic management
Procedia PDF Downloads 2495020 Music as Source Domain: A Cross-Linguistic Exploration of Conceptual Metaphors
Authors: Eleanor Sweeney, Chunyuan Di
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The metaphors people use in everyday discourse do not arise randomly; rather, they develop from our physical experiences in our social and cultural environments. Conceptual Metaphor Theory (CMT) explains that through metaphor, we apply our embodied understanding of the physical world to non-material concepts to understand and express abstract concepts. Our most productive source domains derive from our embodied understanding and allow us to develop primary metaphors, and from primary metaphors, an elaborate, creative world of culturally constructed complex metaphors. Cognitive Linguistics researchers draw upon individual embodied experience for primary metaphors. Socioculturally embodied experience through music has long furnished linguistic expressions in diverse languages, as conceptual metaphors or everyday expressions. Can a socially embodied experience function in the same way as an individually embodied experience in the creation of conceptual metaphors? The authors argue that since music is inherently social and embodied, musical experiences function as a richly motivated source domain. The focus of this study is socially embodied musical experience which is then reflected and expressed through metaphors. This cross-linguistic study explores music as a source domain for metaphors of social alignment in English, French, and Chinese. The authors explored two public discourse sites, Facebook and Linguée, in order to collect linguistic metaphors from three different languages. By conducting this cross-linguistic study, cross-cultural similarities and differences in metaphors for which music is the source domain can be examined. Different musical elements, such as melody, speed, rhythm and harmony, are analyzed for their possible metaphoric meanings of social alignment. Our findings suggest that the general metaphor cooperation is music is a productive metaphor with some subcases, and that correlated social behaviors can be metaphorically expressed with certain elements in music. For example, since performance is a subset of the category behavior, there is a natural mapping from performance in music to behavior in social settings: social alignment is musical performance. Musical performance entails a collective social expectation that exerts control over individual behavior. When individual behavior does not align with the collective social expectation, music-related expressions are often used to express how the individual is violating social norms. Moreover, when individuals do align their behavior with social norms, similar musical expressions are used. Cooperation is a crucial social value in all cultures, indeed it is a key element of survival, and music provides a coherent, consistent, and rich source domain—one based upon a universal and definitive cultural practice.Keywords: Chinese, Conceptual Metaphor Theory, cross-linguistic, culturally embodied experience, English, French, metaphor, music
Procedia PDF Downloads 1755019 Empirical Acceleration Functions and Fuzzy Information
Authors: Muhammad Shafiq
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In accelerated life testing approaches life time data is obtained under various conditions which are considered more severe than usual condition. Classical techniques are based on obtained precise measurements, and used to model variation among the observations. In fact, there are two types of uncertainty in data: variation among the observations and the fuzziness. Analysis techniques, which do not consider fuzziness and are only based on precise life time observations, lead to pseudo results. This study was aimed to examine the behavior of empirical acceleration functions using fuzzy lifetimes data. The results showed an increased fuzziness in the transformed life times as compare to the input data.Keywords: acceleration function, accelerated life testing, fuzzy number, non-precise data
Procedia PDF Downloads 3035018 Numerical Modeling the Cavitating Flow in Injection Nozzle Holes
Authors: Ridha Zgolli, Hatem Kanfoudi
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Cavitating flows inside a diesel injection nozzle hole were simulated using a mixture model. A 2D numerical model is proposed in this paper to simulate steady cavitating flows. The Reynolds-averaged Navier-Stokes equations are solved for the liquid and vapor mixture, which is considered as a single fluid with variable density which is expressed as function of the vapor volume fraction. The closure of this variable is provided by the transport equation with a source term TEM. The processes of evaporation and condensation are governed by changes in pressure within the flow. The source term is implanted in the CFD code ANSYS CFX. The influence of numerical and physical parameters is presented in details. The numerical simulations are in good agreement with the experimental data for steady flow.Keywords: cavitation, injection nozzle, numerical simulation, k–ω
Procedia PDF Downloads 4055017 Manufacturing Process and Cost Estimation through Process Detection by Applying Image Processing Technique
Authors: Chalakorn Chitsaart, Suchada Rianmora, Noppawat Vongpiyasatit
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In order to reduce the transportation time and cost for direct interface between customer and manufacturer, the image processing technique has been introduced in this research where designing part and defining manufacturing process can be performed quickly. A3D virtual model is directly generated from a series of multi-view images of an object, and it can be modified, analyzed, and improved the structure, or function for the further implementations, such as computer-aided manufacturing (CAM). To estimate and quote the production cost, the user-friendly platform has been developed in this research where the appropriate manufacturing parameters and process detections have been identified and planned by CAM simulation.Keywords: image processing technique, feature detections, surface registrations, capturing multi-view images, Production costs and Manufacturing processes
Procedia PDF Downloads 2535016 Evaluation of Cooperative Hand Movement Capacity in Stroke Patients Using the Cooperative Activity Stroke Assessment
Authors: F. A. Thomas, M. Schrafl-Altermatt, R. Treier, S. Kaufmann
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Stroke is the main cause of adult disability. Especially upper limb function is affected in most patients. Recently, cooperative hand movements have been shown to be a promising type of upper limb training in stroke rehabilitation. In these movements, which are frequently found in activities of daily living (e.g. opening a bottle, winding up a blind), the force of one upper limb has to be equally counteracted by the other limb to successfully accomplish a task. The use of standardized and reliable clinical assessments is essential to evaluate the efficacy of therapy and the functional outcome of a patient. Many assessments for upper limb function or impairment are available. However, the evaluation of cooperative hand movement tasks are rarely included in those. Thus, the aim of this study was (i) to develop a novel clinical assessment (CASA - Cooperative Activity Stroke Assessment) for the evaluation of patients’ capacity to perform cooperative hand movements and (ii) to test its inter- and interrater reliability. Furthermore, CASA scores were compared to current gold standard assessments for upper extremity in stroke patients (i.e. Fugl-Meyer Assessment, Box & Blocks Test). The CASA consists of five cooperative activities of daily living including (1) opening a jar, (2) opening a bottle, (3) open and closing of a zip, (4) unscrew a nut and (5) opening a clipbox. Here, the goal is to accomplish the tasks as fast as possible. In addition to the quantitative rating (i.e. time) which is converted to a 7-point scale, also the quality of the movement is rated in a 4-point scale. To test the reliability of CASA, fifteen stroke subjects were tested within a week twice by the same two raters. Intra-and interrater reliability was calculated using the intraclass correlation coefficient (ICC) for total CASA score and single items. Furthermore, Pearson-correlation was used to compare the CASA scores to the scores of Fugl-Meyer upper limb assessment and the box and blocks test, which were assessed in every patient additionally to the CASA. ICC scores of the total CASA score indicated an excellent- and single items established a good to excellent inter- and interrater reliability. Furthermore, the CASA score was significantly correlated to the Fugl-Meyer and Box & Blocks score. The CASA provides a reliable assessment for cooperative hand movements which are crucial for many activities of daily living. Due to its non-costly setup, easy and fast implementation, we suggest it to be well suitable for clinical application. In conclusion, the CASA is a useful tool in assessing the functional status and therapy related recovery in cooperative hand movement capacity in stroke patients.Keywords: activitites of daily living, clinical assessment, cooperative hand movements, reliability, stroke
Procedia PDF Downloads 3225015 Study on the Geometric Similarity in Computational Fluid Dynamics Calculation and the Requirement of Surface Mesh Quality
Authors: Qian Yi Ooi
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At present, airfoil parameters are still designed and optimized according to the scale of conventional aircraft, and there are still some slight deviations in terms of scale differences. However, insufficient parameters or poor surface mesh quality is likely to occur if these small deviations are embedded in a future civil aircraft with a size that is quite different from conventional aircraft, such as a blended-wing-body (BWB) aircraft with future potential, resulting in large deviations in geometric similarity in computational fluid dynamics (CFD) simulations. To avoid this situation, the study on the CFD calculation on the geometric similarity of airfoil parameters and the quality of the surface mesh is conducted to obtain the ability of different parameterization methods applied on different airfoil scales. The research objects are three airfoil scales, including the wing root and wingtip of conventional civil aircraft and the wing root of the giant hybrid wing, used by three parameterization methods to compare the calculation differences between different sizes of airfoils. In this study, the constants including NACA 0012, a Reynolds number of 10 million, an angle of attack of zero, a C-grid for meshing, and the k-epsilon (k-ε) turbulence model are used. The experimental variables include three airfoil parameterization methods: point cloud method, B-spline curve method, and class function/shape function transformation (CST) method. The airfoil dimensions are set to 3.98 meters, 17.67 meters, and 48 meters, respectively. In addition, this study also uses different numbers of edge meshing and the same bias factor in the CFD simulation. Studies have shown that with the change of airfoil scales, different parameterization methods, the number of control points, and the meshing number of divisions should be used to improve the accuracy of the aerodynamic performance of the wing. When the airfoil ratio increases, the most basic point cloud parameterization method will require more and larger data to support the accuracy of the airfoil’s aerodynamic performance, which will face the severe test of insufficient computer capacity. On the other hand, when using the B-spline curve method, average number of control points and meshing number of divisions should be set appropriately to obtain higher accuracy; however, the quantitative balance cannot be directly defined, but the decisions should be made repeatedly by adding and subtracting. Lastly, when using the CST method, it is found that limited control points are enough to accurately parameterize the larger-sized wing; a higher degree of accuracy and stability can be obtained by using a lower-performance computer.Keywords: airfoil, computational fluid dynamics, geometric similarity, surface mesh quality
Procedia PDF Downloads 2255014 Research on Fuzzy Test Framework Based on Concolic Execution
Authors: Xiong Xie, Yuhang Chen
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Vulnerability discovery technology is a significant field of the current. In this paper, a fuzzy framework based on concolic execution has been proposed. Fuzzy test and symbolic execution are widely used in the field of vulnerability discovery technology. But each of them has its own advantages and disadvantages. During the path generation stage, path traversal algorithm based on generation is used to get more accurate path. During the constraint solving stage, dynamic concolic execution is used to avoid the path explosion. If there is external call, the concolic based on function summary is used. Experiments show that the framework can effectively improve the ability of triggering vulnerabilities and code coverage.Keywords: concolic execution, constraint solving, fuzzy test, vulnerability discovery
Procedia PDF Downloads 2335013 A Low-Cost Vision-Based Unmanned Aerial System for Extremely Low-Light GPS-Denied Navigation and Thermal Imaging
Authors: Chang Liu, John Nash, Stephen D. Prior
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This paper presents the design and implementation details of a complete unmanned aerial system (UAS) based on commercial-off-the-shelf (COTS) components, focusing on safety, security, search and rescue scenarios in GPS-denied environments. In particular, the aerial platform is capable of semi-autonomously navigating through extremely low-light, GPS-denied indoor environments based on onboard sensors only, including a downward-facing optical flow camera. Besides, an additional low-cost payload camera system is developed to stream both infrared video and visible light video to a ground station in real-time, for the purpose of detecting sign of life and hidden humans. The total cost of the complete system is estimated to be $1150, and the effectiveness of the system has been tested and validated in practical scenarios.Keywords: unmanned aerial system, commercial-off-the-shelf, extremely low-light, GPS-denied, optical flow, infrared video
Procedia PDF Downloads 3335012 Characterization and Antimicrobial Properties of Functional Polypropylene Films Incorporated with AgSiO2, AgZn, and AgZ Useful as Returnable Packaging in Seafood Distribution
Authors: Suman Singh, Myungho Lee, Insik Park, Yangjai Shin, Youn Suk Lee
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Active antimicrobial films prepared by incorporating AgSiO2, AgZn, and AgZ at 1%, 3%, 5%, 10% (w/w) into polypropylene (PP) matrix. Complete thermal, structural, mechanical and functional characterization were carried out of all formulations and determined the antimicrobial efficiency and returnable antimicrobial efficiency according to the Japanese Industrial Standard method. The morphology of the films showed agglomerates of particles in the composites. The active formulation had decreased elongation compared to the pure PP sample. Thermal analyses indicated that the active formulation compositions had increased thermal stability. The films showed 50% antimicrobial properties after the fifth wash against the tested microorganisms, presenting better activity against Gram negative organisms than Gram positive ones. These findings suggest that PP films with AgSiO2, AgZn, and AgZ particles could provide a significant contribution to the quality and safety of seafood in the distribution chain.Keywords: antimicrobial film, properties and characterization, returnable packaging, sea food
Procedia PDF Downloads 3695011 The Impact of Innovation Efficiency on the Production of New Knowledge: A Manufacturing Firm Level Perspective
Authors: Vasilios Kanellopoulos
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The present paper examines the effect of innovation efficiency on the production of new knowledge from a firm level perspective. It resorts to the Greek version of community innovation survey (CIS 2012-2014 microdata) and employs 1274 firms of the manufacturing, which constitutes the main sector of examination. It assumes a knowledge production function (KPF) and finds that R&D spillovers related to the expenditures on innovation activities, internal R&D, external R&D, skilled labor, and the expenditures in the acquisition of machinery have a positive and significant effect on the production of new knowledge when OLS techniques are applied. However, innovation efficiency comes from a Banker and Morey (1986) data envelopment analysis (DEA) with categorical variables has a statistically insignificant impact on the production of new knowledge measured by firm’s turnover.Keywords: firms, innovation efficiency, production of new knowledge, R&D spillovers
Procedia PDF Downloads 1415010 All Optical Wavelength Conversion Based On Four Wave Mixing in Optical Fiber
Authors: Surinder Singh, Gursewak Singh Lovkesh
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We have designed wavelength conversion based on four wave mixing in an optical fiber at 10 Gb/s. The power of converted signal increases with increase in signal power. The converted signal power is investigated as a function of input signal power and pump power. On comparison of converted signal power at different value of input signal power, we observe that best converted signal power is obtained at -2 dBm input signal power for both up conversion as well as for down conversion. Further, FWM efficiency, quality factor is observed for increase in input signal power and optical fiber length.Keywords: FWM, optical fiiber, wavelngth converter, quality
Procedia PDF Downloads 5805009 Evaluation of Wind Fragility for Set Anchor Used in Sign Structure in Korea
Authors: WooYoung Jung, Buntheng Chhorn, Min-Gi Kim
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Recently, damage to domestic facilities by strong winds and typhoons are growing. Therefore, this study focused on sign structure among various vulnerable facilities. The evaluation of the wind fragility was carried out considering the destruction of the anchor, which is one of the various failure modes of the sign structure. The performance evaluation of the anchor was carried out to derive the wind fragility. Two parameters were set and four anchor types were selected to perform the pull-out and shear tests. The resistance capacity was estimated based on the experimental results. Wind loads were estimated using Monte Carlo simulation method. Based on these results, we derived the wind fragility according to anchor type and wind exposure category. Finally, the evaluation of the wind fragility was performed according to the experimental parameters such as anchor length and anchor diameter. This study shows that the depth of anchor was more significant for the safety of structure compare to diameter of anchor.Keywords: sign structure, wind fragility, set anchor, pull-out test, shear test, Monte Carlo simulation
Procedia PDF Downloads 2915008 The Process of Irony Comprehension in Young Children: Evidence from Monolingual and Bilingual Preschoolers
Authors: Natalia Banasik
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Comprehension of verbal irony is an example of pragmatic competence in understanding figurative language. The knowledge of how it develops may shed new light on the understanding of social and communicative competence that is crucial for one's effective functioning in the society. Researchers agree it is a competence that develops late in a child’s development. One of the abilities that seems crucial for irony comprehension is theory of mind (ToM), that is the ability to understand that others may have beliefs, desires and intentions different from one’s own. Although both theory of mind and irony comprehension require the ability to understand the figurative use of the false description of the reality, the exact relationship between them is still unknown. Also, even though irony comprehension in children has been studied for over thirty years, the results of the studies are inconsistent as to the age when this competence are acquired. The presented study aimed to answer questions about the developmental trajectories of irony comprehension and ascribing function to ironic utterances by preschool children. Specifically, we were interested in how it is related to the development of ToM and how comprehension of the function of irony changes with age. Data was collected from over 150 monolingual, Polish-speaking children and (so far) thirty bilingual children speaking Polish and English who live in the US. Four-, five- and six-year-olds were presented with a story comprehension task in the form of audio and visual stimuli programmed in the E-prime software (pre-recorded narrated stories, some of which included ironic utterances, and pictures accompanying the stories displayed on a touch screen). Following the presentation, the children were then asked to answer a series of questions. The questions checked the children’s understanding of the intended utterance meaning, evaluation of the degree to which it was funny and evaluation of how nice the speaker was. The children responded by touching the screen, which made it possible to measure reaction times. Additionally, the children were asked to explain why the speaker had uttered the ironic statement. Both quantitive and qualitative analyses were applied. The results of our study indicate that for irony recognition there is a significant difference among the three age groups, but what is new is that children as young as four do understand the real meaning behind the ironic statement as long as the utterance is not grammtically or lexically complex also, there is a clear correlation of ToM and irony comprehension. Although four-year olds and six-year olds understand the real meaning of the ironic utterance, it is not earlier than at the age of six when children start to explain the reason of using this marked form of expression. They talk about the speaker's intention to tell a joke, be funny, or to protect the listener's emotions. There are also some metalinguistic references, such as "mommy sometimes says things that don't make sense and this is called a metaphor".Keywords: child's pragmatics, figurative speech, irony comprehension in children, theory of mind and irony
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