Search results for: social work teaching methods

Authors: S. Kongtun-Janphuk, S. Niwitpong Jr., J. Saengsai

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Low-sugar snack bars were formulated with 3 main formulas depending on the main ingredient, which were peanut-green bean-sesame, apple, and prune. The most acceptable formula of each group was obtained by sensory evaluation using a nine-point hedonic scale. The moisture content, total ash, protein, fat and fiber were analyzed by the standard methods of AOAC. The peanut-mung bean-sesame snack bar showed the highest protein content (88.32%) and total fat (0.48%) with the lowest of fiber content (0.01%) while the prune formula showed the lowest protein content (71.91%) and total fat (0.21%) with the highest of fiber content (0.03%). This result indicated that the prune formula could be used as diet food to assist in weight loss program.

Keywords: low-sugar snack bar, diet food, nutrition analysis, food formulation

Procedia PDF Downloads 382

Authors: Gang Liu, Can Wang, Runnan Zhang, Quan Wang, Huimin Song, Shaomin Ji

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Biba model can protect information integrity but might deny various non-malicious access requests of the subjects, thereby decreasing the availability in the system. Therefore, a mechanism that allows exceptional access control is needed. Break the Glass (BTG) strategies refer an efficient means for extending the access rights of users in exceptional cases. These strategies help to prevent a system from stagnation. An approach is presented in this work for integrating Break the Glass strategies into the Biba model. This research proposes a model, BTG-Biba, which provides both an original Biba model used in normal situations and a mechanism used in emergency situations. The proposed model is context aware, can implement a fine-grained type of access control and primarily solves cross-domain access problems. Finally, the flexibility and availability improvement with the use of the proposed model is illustrated.

Keywords: Biba model, break the glass, context, cross-domain, fine-grained

Procedia PDF Downloads 531

Authors: J. Uka, B. McKay, T. Minton, O. Adole, R. Lewis, S. J. Glanvill, L. Anguilano

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Effective heat treatment conditions to obtain maximum aluminium swarf recycling are investigated in this work. Aluminium swarf briquettes underwent treatments at different temperatures and cooling times to investigate the improvements obtained in the recovery of aluminium metal. The main issue for the recovery of the metal from swarfs is to overcome the constraints due to the oxide layers present in high concentration in the swarfs since they have a high surface area. Briquettes supplied by Renishaw were heat treated at 650, 700, 750, 800 and 850 ℃ for 1-hour and then cooled at 2.3, 3.5 and 5 ℃/min. The resulting material was analysed using SEM EDX to observe the oxygen diffusion and aluminium coalescence at the boundary between adjacent swarfs. Preliminary results show that, swarf needs to be heat treated at a temperature of 850 ℃ and cooled down slowly at 2.3 ℃/min to have thin and discontinuous alumina layers between the adjacent swarf and consequently allowing aluminium coalescence. This has the potential to save energy and provide maximum financial profit in preparation of swarf briquettes for recycling.

Keywords: reuse, recycle, aluminium, swarf, oxide layers

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Authors: Prasanta Sutradhar, Mitali Saha

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With an increasing awareness of green and clean energy, zinc oxide based solar cells were found to be suitable candidates for cost-effective and environmentally friendly energy conversion devices. In this work, we have reported the green synthesis of zinc oxide nanoparticles (ZnO) by thermal method and under microwave irradiation using the aqueous extract of tomatoes as non-toxic and ecofriendly reducing material. The synthesized ZnO nanoparticles were characterised by UV-Visible spectroscopy (UV-Vis), infra-red spectroscopy (IR), particle size analyser (DLS), scanning electron microscopy (SEM), atomic force microscopy (AFM), and X- ray diffraction study (XRD). A series of ZnO nanocomposites with titanium dioxide nanoparticles (TiO2) and graphene oxide (GO) were prepared for photovoltaic application. Structural and morphological studies of these nanocomposites were carried out using UV-vis, SEM, XRD, and AFM. The current-voltage measurements of the nanocomposites demonstrated enhanced power conversion efficiency of 6.18% in case of ZnO/GO/TiO2 nanocomposite.

Keywords: ZnO, green synthesis, microwave, nanocomposites, I-V characteristics

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Authors: Hemalatha Rallapalli, K. Lal Kishore

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In comparison to systems that are typically designed to provide capabilities over a narrow frequency range through hardware elements, the next generation cognitive radios are intended to implement a broader range of capabilities through efficient spectrum exploitation. This offers the user the promise of greater flexibility, seamless roaming possible on different networks, countries, frequencies, etc. It requires true paradigm shift i.e., liberalization over a wide band of spectrum as well as a growth path to more and greater capability. This work contributes towards the design and implementation of an open spectrum access (OSA) feature to unlicensed users thus offering a frequency agile radio platform that is capable of performing spectrum sensing over a wideband. Thus, an ultra-wideband (UWB) radio, which has the intelligence of spectrum sensing only, unlike the cognitive radio with complete intelligence, is named as a Smart Software Radio (SSR). The spectrum sensing mechanism is implemented based on energy detection. Simulation results show the accuracy and validity of this method.

Keywords: cognitive radio, energy detection, software radio, spectrum sensing

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Authors: Seyedeh Faranak Baniahmad, Soroor Yousefi

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Osteoporosis is a bone disease which increases the bone fracture risk, reduces the bone mineral density (BMD) and alters the amount and variety of proteins in bones. Antiresorptive therapy is one the most popular Osteoporosis treatment methods. In this method the bisphosphonates, hormones, calcitonin or the selective estrogen receptor modulators is replaced. In order to reduce undesirable effects and to increase the bioavailability of drug agents, the controlled drug delivery systems have been utilized. In current study, the controlled release of Alendronate from LDH-PCL with (0, 5, 10, 15 % wt. of LDH) was investigated. The results showed that the release of alendronate from the lamellar LDH incorporated into the PCL matrix is much slower than the release of alendronate from the PCL. Therefore such systems are very promising, in which the antiresorptive drug has to remain in the matrix for longer time and can be released in controlled manner.

Keywords: osteoporosis, alendronate, poly (ε–caprolactone), layered double hydroxide

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Authors: Broderick Crawford, Ricardo Soto, Natalia Berrios, Eduardo Olguin

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In this paper, we present a binary cat swarm optimization for solving the Set covering problem. The set covering problem is a well-known NP-hard problem with many practical applications, including those involving scheduling, production planning and location problems. Binary cat swarm optimization is a recent swarm metaheuristic technique based on the behavior of discrete cats. Domestic cats show the ability to hunt and are curious about moving objects. The cats have two modes of behavior: seeking mode and tracing mode. We illustrate this approach with 65 instances of the problem from the OR-Library. Moreover, we solve this problem with 40 new binarization techniques and we select the technical with the best results obtained. Finally, we make a comparison between results obtained in previous studies and the new binarization technique, that is, with roulette wheel as transfer function and V3 as discretization technique.

Keywords: binary cat swarm optimization, binarization methods, metaheuristic, set covering problem

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Authors: R. Bennai, H. Ait Atmane, H. Fourne, B. Ayache

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In this work, an analytical approach using a refined theory of hyperbolic shear deformation of a beam was developed to study the buckling of graduated sandwiches beams under different boundary conditions. The effects of transverse shear strains and the transverse normal deformation are considered. The constituent materials of the beam are supposed gradually variable depending on the height direction based on a simple power distribution law in terms of the volume fractions of the constituents; the two materials with which we worked are metals and ceramics. The core layer is taken homogeneous and made of an isotropic material; while the banks layers consist of functionally graded materials with a homogeneous fraction compared to the middle layer. In the end, illustrative examples are presented to show the effects of changes in different parameters such as (material graduation, the stretching effect of the thickness, boundary conditions and thickness ratio-length) on the vibration free of an FGM sandwich beams.

Keywords: FGM materials, refined shear deformation theory, stretching effect, buckling

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Authors: Madiha Khan, Sidrah Ramzan, Seemab Khan, Shahzad Hassan, Kamran Saeed

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Measuring semantic similarity between texts is calculating semantic relatedness between texts using various techniques. Our web application (Measuring Relatedness of Concepts-MRC) allows user to input two text corpuses and get semantic similarity percentage between both using WordNet. Our application goes through five stages for the computation of semantic relatedness. Those stages are: Preprocessing (extracts keywords from content), Feature Extraction (classification of words into Parts-of-Speech), Synonyms Extraction (retrieves synonyms against each keyword), Measuring Similarity (using keywords and synonyms, similarity is measured) and Visualization (graphical representation of similarity measure). Hence the user can measure similarity on basis of features as well. The end result is a percentage score and the word(s) which form the basis of similarity between both texts with use of different tools on same platform. In future work we look forward for a Web as a live corpus application that provides a simpler and user friendly tool to compare documents and extract useful information.

Keywords: Graphviz representation, semantic relatedness, similarity measurement, WordNet similarity

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Authors: Alireza Pour Ebrahimi, Vahid Abasi

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Recently by the extension of internet usage, Research on the intrusion detection system takes a significant importance. Many of improvement systems prevent internal and external network attacks by providing security through firewalls and antivirus. In recently years, intrusion detection systems gradually turn from host-based systems and depend on O.S to the distributed systems which are running on multiple O.S. In this work, by considering the diversity of computer networks whit respect to structure, architecture, resource, services, users and also security goals requirement a fully distributed collaborative intrusion detection system based on peer to peer architecture is suggested. in this platform each partner device (matched device) considered as a peer-to-peer network. All transmitted information to network are visible only for device that use security scanning of a source. Experimental results show that the distributed architecture is significantly upgradeable in respect to centralized approach.

Keywords: network, intrusion detection system, peer to peer, internal and external network

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Authors: Dominik Krimpmann

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Information technology and information systems are currently at a tipping point. The digital age fundamentally transforms a large number of industries in the ways they work. Lines between business and technology blur. Researchers have acknowledged that this is the time in which the IT/IS organisation needs to re-strategise itself. In this paper, the author provides a structured review of the IS and organisation design literature addressing the question of how the digital age changes the design categories of an IT/IS organisation design. The findings show that most papers just analyse single aspects of either IT/IS relevant information or generic organisation design elements but miss a holistic ‘big-picture’ onto an IT/IS organisation design. This paper creates a holistic IT/IS organisation design framework bringing together the IS research strand, the digital strand and the generic organisation design strand. The research identified four IT/IS organisation design categories (strategy, structure, processes and people) and discusses the importance of two additional categories (sourcing and governance). The authors findings point to a first anchor point from which further research needs to be conducted to develop a holistic IT/IS organisation design framework.

Keywords: IT/IS strategy, IT/IS organisation design, digital age, organisational effectiveness, literature review

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Authors: Djehich Mohamed Yousri

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This paper aims to address the dialectic of law and politics in the philosophy of the state of the philosopher Hegel by addressing the concept of law, which refers to its general meaning to the set of rules and legislation that man sets to apply them within society, as it is considered one of the primary and necessary conditions for the functioning of And organizing social life, when it defines the rights and duties of every individual belonging to the state, by approaching it with central concepts in political philosophy, such as the state, freedom and the people. The most prominent result that we reached through our analysis of the details of the problematic research is the relationship between law and politics in the philosophical system of Hegel; on the one hand, We find that the state is rational only to the extent that it resorts to the law and works under it, and the latter does not realize its essence and effectiveness unless it is extracted from the customs, traditions, and culture of the people so that it does not conflict with the ideal goal of its existence, which is to achieve freedom and protect it from all possible. A state does not mean at all to reduce the freedom of the people, so there is no conflict between law and freedom.

Keywords: hegel, the law, country, freedom, citizen

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Authors: R. Komsa-Penkova, G. Golemanov, G. Georgieva, K. Popovski, N. Slavov, P. Ivanov, K. Kovacheva, S. Rathee, E. Konova, A. Blajev

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Leptin and PAI-1 are important cytokines and may play a role in the regulation of PCOS development. PCOS is frequently associated with obesity, high BMI index and consequently with increased risk of metabolic disorders. The aim of the present study was to evaluate PAI-1 levels, genetic influence of the carriage of 675 4G/5G polymorphism in PAI-1 gene and leptin as a marker of obesity in the development of PCOS. Methods: Genotyping in 84 patients with PCOS and PCO and 100 healthy control subjects to detect single nucleotide deletion 675 G in the promoter of PAI-1 gene. The present study provides evidence that SNP 4G in the PAI-1 gene is associated with early pregnancy losses in patients with polycystosis. Further to this, there is a correlation between leptin levels, PAI-1 levels and BMI in the patients with PCOS, which confirms the role of obesity as a risk factor for PCOS.

Keywords: carriage of 675 4G/5G polymorphism, PCOS, early pregnancy losses, PAI-1 gene

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Authors: Ana Cleide Vieira Gomes Guimbal de Aquino

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Sound communication is present in most vertebrates, from fish, mainly in species that live in murky waters, to some species of reptiles, anuran amphibians, birds, and mammals, including primates. There are, in fact, relevant similarities between human language and animal sound communication, and among these similarities are the vocalizations called calls. The first specific call in human babies is crying, which has a characteristic prosodic contour and is motivated most of the time by the need for food and by affecting the puppy-caregiver interaction, with a view to communicating the necessities and food requests and guaranteeing the survival of the species. The present work aims to articulate speech processing in the motor context with aspects of the project entitled emotional states and vocalization: a comparative study of the prosodic contours of crying in human and non-human animals. First, concepts of speech motor processing and general aspects of speech evolution will be presented to relate these two approaches to animal sound communication.

Keywords: speech motor processing, animal communication, animal behaviour, language acquisition

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Authors: Serier Bouchenak NORA, Bouguerni ABDELMADJID

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Algeria is a Mediterranean country which provides an ideal habitat for a wide range of species of medicinal plants. The objective of this current work is to extract the gel contained in the leaves of Aloe vera in order to formulate an oral gel as a prebiotic and see its effects on probiotics (lactic and pseudo lactic bacteria and bifido bacterium). Aloe vera polysaccharid extract is a matrix mainly composed of non-digestible oligosaccharids or slow-fermentation polysaccharids, as this produces a lower pH. The behavior of Aloe vera during in vitro fermentation of the colon was similar to that of lactulose, indicating the possibility of using Aloe vera and its polysaccharids extracts as a prebiotic. The microbiological control of the two kinds of bacteria (bifidobacteria and staphylococci) has demonstrated the gel capacity to stimulate them by these bioactive compounds. The generation time of Bifidobacteria in fermented milk with added prebiotic Aloe vera gel is 80.408 min with a µ growth rate equal to 0.012 min -1. The doubling time is 61.459 min with a growth rate µ equal to 0.016 min -1 for the Streptococcus sp. species.

Keywords: aloe vera, probiotics, prebiotics, growth rate, bifidobacteria

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Authors: Venugopal Kummamuru

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Corporate Governance (CG) is of utmost importance for running a company ethically. It is essential for the growth and success of the corporation. It is intended to increase the accountability of an organization to the larger context of the business environment. The general principles of CG include and are related to Shareholder recognition, Stakeholder interests, and focus on Corporate Social Responsibility (CSR), Clear Board responsibilities, Ethical behavior, and Business transparency. Network Marketing Organizations (NMOs) focus on marketing through direct-sales using people who are associated with the organization but are not their employees. This paper tries to study the importance of Ethics and CSR in an NMO and suggest a basic guideline for CG in NMO(s). This paper could be used as a basis or starting point for conducting an in-depth research to understand the difference in CG practices between NMO(s) and other organizations and define a standard set of guidelines for CG practice.

Keywords: corporate governance, corporate responsibility, direct selling, network marketing

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Authors: E. O. Egieyeh, N. Butler, R. Coetzee, M. Van Huyssteen, A. Bheekie

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Background: High rate of maternal and child mortality is a global concern. Nationally, it constitutes one of South Africa’s quadruple burdens of diseases. Pharmacists have a crucial role in maternal and child health care delivery and as such should be equipped with adequate knowledge and skill required to contribute to maternal and child well-being. The International Pharmaceutical Federation statement of policy (2013) outlines pharmacist-led interventions in accordance with the World Health Organisation’s interventions in maternal, new-born and child health care. The South African Pharmacy Council’s guideline on Good Pharmacy Practice (2010) also stipulates the minimum standards required to participate in reproductive, maternal and child care. Pharmacy schools are obliged to train pharmacy students to meet priority health needs of the population so that graduates are ‘fit for purpose’. The purpose of the study is to evaluate the knowledge and skill of final year pharmacy students at a university in South Africa to determine their preparedness to contribute effectively to maternal and child health care. Method: A quantitative, descriptive, non-randomized baseline study was conducted among the final year students at the School of Pharmacy. Data was collected using a questionnaire designed in sections to assess knowledge of contraception, maternal and child health directed at the primary care level and framed within the scope of practice required of an entry-level generalist pharmacist. Participants’ skill in infant growth assessment was assessed in a section of the questionnaire in a written format. Participants ticked the topics they had been exposed to on a curriculum content assessment tool which was not graded. A pilot study examined the clarity and suitability of question items, and duration to complete the questionnaire. A score of 50% in each section of the questionnaire indicated a pass. The questionnaire was delivered in campus lecture venue. Results: Of the 102 students in final year, 53 (52%) students consented to participate in the study. Only 13.2% of participants scored above 50% in each section. Forty five (85%) participants scored above 50% in the contraception section while 40 (75%) scored less than 50% in the skills assessment. Less than half (45.3%) of the participants had a total score above 50%. Being a parent or working part-time as pharmacist assistance did not have any influence on the performance of the participants. Evaluation of participants’ curriculum content exposure showed differences in exposure to the various topics. Exposure to contraception teaching received the most recognition. Conclusion: Maternal and child health curriculum content should be reviewed at the university to enhance the knowledge and skill of pharmacy graduates.

Keywords: final year pharmacy students, knowledge and skill, maternal and child health, South Africa

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Authors: Adrian Morris, Rodney Phillips, Mattia Tabacchi

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Minimizing construction noise and vibration impacts is a key challenge for major infrastructure projects in urban environments. Before commencing construction works, Construction Noise and Vibration Management Plan (CNVMP) and Construction Noise and Vibration Impact Statements (CNVIS) are required to be prepared and submitted to the relevant government authorities for review and approval. However, the assessment of potential impacts from work activities at pre-approval stage may be inaccurate as works methodology and scheduling are yet to be determined. In response, noise and vibration management tools have been developed to refine and supplement the CNVIS as works progress. These tools have been successfully implemented in major infrastructure projects allowing contractors to plan and assess construction works in a cost effective and timely manner. As a result, noise and vibration management tools have been incorporated into management plans and are increasingly required by regulators.

Keywords: noise management, environmental noise, infrastructure projects, construction, vibration, cost effective

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Authors: Lucy Jackson, Celyn Walters, Steve Eckersley, Mini Rai, Simon Hadfield

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Space robots will play an integral part in exploring the universe and beyond. A correctly designed space robot will facilitate OOA, satellite servicing and ADR. However, problems arise when trying to design such a system as it is a highly complex multidimensional problem into which there is little research. Current design techniques are slow and specific to terrestrial manipulators. This paper presents a solution to the slow speed of robotic hardware design, and generalizes the technique to free-flying space robots. It presents Ta-DAH Design, an automated design approach that utilises a multi-objective cost function in an iterative and automated pipeline. The design approach leverages prior knowledge and facilitates the faster output of optimal designs. The result is a system that can optimise the size of the base spacecraft, manipulator and some key subsystems for any given task. Presented in this work is the methodology behind Ta-DAH Design and a number optimal space robot designs.

Keywords: space robots, automated design, on-orbit operations, hardware design

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Authors: Mohssen Amiri

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Lack of motivation among students in learning English can be considered as one of the main obstacles faced by parents, teachers and college/school administrators in Gulf countries and Iran. The question is why this problem still exists among EFL students’ despite of various new methodologies that colleges are implementing by native and non-native instructors. In the paper, it has been explained that why many students fail to know the basic knowledge and conversations of English language even after completing academic levels of colleges. In this study, the answers of all questions have been covered by introducing the concept of the psychology of learning and the importance of motivation which are the main discussions of this study. Additionally, the paper has illustrated that how psychology is the key of success in learning English and how it develops motivation and confidence dramatically among students especially on speaking skill. The study shows that psychology is 70% of success and 30% are the methods and materials that we implement to teach in the classroom. Therefore, this is the role of teachers to develop 70% of positive motivation and psychology among students. The approach of study is descriptive, and the focus will be on speaking skill.

Keywords: psychology, motivation, communication, learning

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Authors: Anu Soikkeli

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Early 20th century functionalism aimed at generalising living and rationalising construction, thus laying the foundation for the standardisation of construction components and products. From the 1930s onwards, all measurement and quality instructions for building products, different types of building components, descriptions of working methods complying with advisable building practises, planning, measurement and calculation guidelines, terminology, etc. were called standards. Standardisation was regarded as a necessary prerequisite for the mass production of housing. This article examines the early stages of standardisation in Finland in the 1940s and 1950s, as reflected on the working history of an individual architect, Erkki Koiso-Kanttila (1914-2006). In 1950 Koiso-Kanttila was appointed the Head of Design of the Finnish Association of Architects’ Building Standards Committee, a position which he held until 1958. His main responsibilities were the development of the RT Building Information File and compiling of the files.

Keywords: architecture, post WWII period, reconstruction, standardisation

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Authors: J. Ranjbarn, A. Alibeigloo

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In this paper, we present an analytical method for analysis of nano-scale spherical shell subjected to thermo-mechanical shocks based on nonlocal elasticity theory. Thermo-mechanical properties of nano shpere is assumed to be temperature dependent. Governing partial differential equation of motion is solved analytically by using Laplace transform for time domain and power series for spacial domain. The results in Laplace domain is transferred to time domain by employing the fast inverse Laplace transform (FLIT) method. Accuracy of present approach is assessed by comparing the the numerical results with the results of published work in literature. Furtheremore, the effects of non-local parameter and wall thickness on the dynamic characteristics of the nano-sphere are studied.

Keywords: nano-scale spherical shell, nonlocal elasticity theory, thermomechanical shock, dynamic response

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Authors: Fadwa Chtioui

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Vital Pulp Therapy (VPT) is nowadays challenging the deep-rooted dogma of root canal treatment, being the only therapeutic option for permanent teeth diagnosed with irreversible pulpitis or carious pulp exposure. Histologic and clinical research has shown that compromised dental pulp can be treated without the full removal or excavation of all healthy pulp, and the outcome of the partial or full pulpotomy followed by a Tricalcium-Silicate-based dressing seems to show promising results in maintaining pulp vitality and preserving affected teeth in the long term. By reviewing recent advances in the techniques of VPT and their clinical effectiveness and safety in permanent teeth with irreversible Pulpitis, this work provides a new understanding of pulp pathophysiology and defense mechanisms and will reform dental practitioners' decision-making in treating irreversible pulpits from root canal therapy to vital pulp therapy by taking advantage of the biological effects of Tricalcium Silicate materials.

Keywords: irreversible pulpitis, vital pulp therapy, pulpotomy, Tricalcium Silicate

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Authors: A. A. Okeola, T. I. Sijuade

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Unreinforced concrete is a comparatively brittle substance when exposed to tensile stresses, the required tensile strength is provided by the introduction of steel which is used as reinforcement. The strength of concrete may be improved tremendously by the addition of fibre. This study focused on investigating the compressive strength of mass concrete mixed with different percentage of plastic fibre. Twelve samples of concrete cubes with varied percentage of plastic fibre at 7, 14 and 28 days of water submerged curing were tested under compression loading. The result shows that the compressive strength of plastic fibre reinforced concrete increased with rise in curing age. The strength increases for all percentage dosage of fibre used for the concrete. The density of the Plastic Fibre Reinforced Concrete (PFRC) also increases with curing age, which implies that during curing, concrete absorbs water which aids its hydration. The least compressive strength obtained with the introduction of plastic fibre is more than the targeted 20 N/mm² recommended for construction work showing that PFRC can be used where significant loading is expected.

Keywords: compressive strength, concrete, curing, density, plastic fibre

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Authors: Irna Farikhah

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Converting low-grade waste heat into useful energy such as sound energy which can then be used to generate acoustic power in a thermoacoustic engine has become an attracting issue for researchers. The generated power in thermoacoustic engine can be used for driving a thermoacoustic cooler when they are installed in a tube. This cooler system can be called as a heat-driven thermoacoustic cooler. In this study, low heating temperature of the engine is discussed. In addition, having high efficiency of the whole cooler is also essential. To design a thermoacoustic cooler having high efficiency with using low-grade waste heat for the engine, the effect of mean pressure is investigated. By increasing the mean pressure, the heating temperature to generate acoustic power can be decreased from 557 °C to 300 °C. Moreover, the efficiency of the engine and cooler regenerators attain 67% and 47% of the upper limit values, respectively and 49% of the acoustical work generated by the engine regenerator is utilized in the cooler regenerator. As a result, the efficiency of the whole cooler becomes 15% of the upper limit value.

Keywords: cooler, mean pressure, performance, thermoacoustic

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Authors: Melanie Kerschner

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Language is our main means of social interaction. News journalism, especially opinion discourse, holds a powerful position in this context. Editorials can be regarded as encounters of different, partially contradictory relationships between discourse participants constructed through the editorial voice. Their primary goal is to shape public opinion by commenting on events already addressed by other journalistic genres in the given newspaper. In doing so, the author tries to establish a consensus over the negotiated matter (i.e. the news event) with the reader. At the same time, he/she claims authority over the “correct” description and evaluation of an event. Yet, how can the relationship and the interaction between the discourse participants, i.e. the journalist, the reader and the news actors represented in the editorial, be best visualized and studied from a cross-cultural perspective? The present research project attempts to give insights into the role of (media) culture in British, Italian and German editorials. For this purpose the presenter will propose a basic framework: the so called “pyramid of discourse participants”, comprising the author, the reader, two types of news actors and the semantic macro-structure (as meta-level of analysis). Based on this framework, the following questions will be addressed: • Which strategies does the author employ to persuade the reader and to prompt him to give his opinion (in the comment section)? • In which ways (and with which linguistic tools) is editorial opinion expressed? • Does the author use adjectives, adverbials and modal verbs to evaluate news actors, their actions and the current state of affairs or does he/she prefer nominal labels? • Which influence do language choice and the related media culture have on the representation of news events in editorials? • In how far does the social context of a given media culture influence the amount of criticism and the way it is mediated so that it is still culturally-acceptable? The following culture-contrastive study shall examine 45 editorials (i.e. 15 per media culture) from six national quality papers that are similar in distribution, importance and the kind of envisaged readership to make valuable conclusions about culturally-motivated similarities and differences in the coverage and assessment of news events. The thematic orientation of the editorials will be the NSA scandal and the reactions of various countries, as this topic was and still is relevant to each of the three media cultures. Starting out from the “pyramid of discourse participants” as underlying framework, eight different criteria will be assigned to the individual discourse participants in the micro-analysis of the editorials. For the purpose of illustration, a single criterion, referring to the salience of authorial opinion, will be selected to demonstrate how the pyramid of discourse participants can be applied as a basis for empirical analysis. Extracts from the corpus shall furthermore enhance the understanding.

Keywords: Micro-analysis of editorials, culture-contrastive research, media culture, interaction between discourse participants, evaluation

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Authors: Farrukh Jamil, Ala'a H. Al-Muhtaseb, Lamya Al-Haj, Mohab A. Al-Hinai

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Date pits are major agricultural waste produced in Oman. Current work was conducted to produce jet fuel and green diesel from hydrodeoxygenation of Date pits oil in the presence of Pd/C catalyst. The hydrodeoxygenation of Date pits oil occurred to be highly efficient at following mild operating conditions such as conditions temperature 300°C pressure 10bar with continuous stirring at 500rpm. Detailed product characterization revealed that large fraction of paraffinic hydrocarbons was found which accounts up to 91.1 % which attributed due to efficient hydrodeoxygenation. Based on the type of components in product oil, it was calculated that the maximum fraction of hydrocarbons formed lies within the range of green diesel 72.0 % then jet fuel 30.4% by using Pd/C catalysts. The densities of product oil were 0.88 kg/m³, the viscosity of products calculated was 3.49 mm²/s. Calorific values for products obtained were 44.11 MJ/kg when Pd/C catalyst was used for hydrodeoxygenation. Based on products analysis it can conclude that Date pits oil could successfully utilize for synthesizing green diesel and jet fuel fraction.

Keywords: biomass, jet fuel, green diesel, catalyst

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Authors: Alastair Hales, Xi Jiang

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Numerical methods are used to evaluate the operation of confined face-to-face piezoelectric fan arrays as pitch, P, between the blades is varied. Both in-phase and counter-phase oscillation are considered. A piezoelectric fan consists of a fan blade, which is clamped at one end, and an extremely low powered actuator. This drives the blade tip’s oscillation at its first natural frequency. Sufficient blade tip speed, created by the high oscillation frequency and amplitude, is required to induce vortices and downstream volume flow in the surrounding air. A single piezoelectric fan may provide the ideal solution for low powered hot spot cooling in an electronic device, but is unable to induce sufficient downstream airflow to replace a conventional air mover, such as a convection fan, in power electronics. Piezoelectric fan arrays, which are assemblies including multiple fan blades usually in face-to-face orientation, must be developed to widen the field of feasible applications for the technology. The potential energy saving is significant, with a 50% power demand reduction compared to convection fans even in an unoptimised state. A numerical model of a typical piezoelectric fan blade is derived and validated against experimental data. Numerical error is found to be 5.4% and 9.8% using two data comparison methods. The model is used to explore the variation of pitch as a function of amplitude, A, for a confined two-blade piezoelectric fan array in face-to-face orientation, with the blades oscillating both in-phase and counter-phase. It has been reported that in-phase oscillation is optimal for generating maximum downstream velocity and flow rate in unconfined conditions, due at least in part to the beneficial coupling between the adjacent blades that leads to an increased oscillation amplitude. The present model demonstrates that confinement has a significant detrimental effect on in-phase oscillation. Even at low pitch, counter-phase oscillation produces enhanced downstream air velocities and flow rates. Downstream air velocity from counter-phase oscillation can be maximally enhanced, relative to that generated from a single blade, by 17.7% at P = 8A. Flow rate enhancement at the same pitch is found to be 18.6%. By comparison, in-phase oscillation at the same pitch outputs 23.9% and 24.8% reductions in peak downstream air velocity and flow rate, relative to that generated from a single blade. This optimal pitch, equivalent to those reported in the literature, suggests that counter-phase oscillation is less affected by confinement. The optimal pitch for generating bulk airflow from counter-phase oscillation is large, P > 16A, due to the small but significant downstream velocity across the span between adjacent blades. However, by considering design in a confined space, counterphase pitch should be minimised to maximise the bulk airflow generated from a certain cross-sectional area within a channel flow application. Quantitative values are found to deviate to a small degree as other geometric and operational parameters are varied, but the established relationships are maintained.

Keywords: piezoelectric fans, low energy cooling, power electronics, computational fluid dynamics

Procedia PDF Downloads 209

Authors: Kefaifi Aissa, Sahraoui Tahar, Kheloufi Abdelkrim, Anas Sabiha, Hannane Farouk

Abstract:

The aim of this study is to show how the Design of Experiments Method (DOE) can be put into use as a practical approach for silica sand etching behavior modeling during its primary step of leaching. In the present work, we have studied etching effect on particle size during a primary step of leaching process on Algerian silica sand with florid acid (HF) at 20% and 30 % during 4 and 8 hours. Therefore, a new purity of the sand is noted depending on the time of leaching. This study was expanded by a numerical approach using a method of experiment design, which shows the influence of each parameter and the interaction between them in the process and approved the obtained experimental results. This model is a predictive approach using hide software. Based on the measured parameters experimentally in the interior of the model, the use of DOE method can make it possible to predict the outside parameters of the model in question and can give us the optimize response without making the experimental measurement.

Keywords: acid leaching, design of experiments method(DOE), purity silica, silica etching

Procedia PDF Downloads 271

Authors: Hyun-Woo Cho

Abstract:

The detection and identification of multivariate manufacturing processes are quite important in order to maintain good product quality. Unusual behaviors or events encountered during its operation can have a serious impact on the process and product quality. Thus they should be detected and identified as soon as possible. This paper focused on the efficient representation of process measurement data in detecting and identifying abnormalities. This qualitative method is effective in representing fault patterns of process data. In addition, it is quite sensitive to measurement noise so that reliable outcomes can be obtained. To evaluate its performance a simulation process was utilized, and the effect of adopting linear and nonlinear methods in the detection and identification was tested with different simulation data. It has shown that the use of a nonlinear technique produced more satisfactory and more robust results for the simulation data sets. This monitoring framework can help operating personnel to detect the occurrence of process abnormalities and identify their assignable causes in an on-line or real-time basis.

Keywords: detection, monitoring, identification, measurement data, multivariate techniques

Procedia PDF Downloads 224