Search results for: graphene oxide paper
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 25998

Search results for: graphene oxide paper

15888 Comparison of Wind Fragility for Window System in the Simplified 10 and 15-Story Building Considering Exposure Category

Authors: Viriyavudh Sim, WooYoung Jung

Abstract:

Window system in high rise building is occasionally subjected to an excessive wind intensity, particularly during typhoon. The failure of window system did not affect overall safety of structural performance; however, it could endanger the safety of the residents. In this paper, comparison of fragility curves for window system of two residential buildings was studied. The probability of failure for individual window was determined with Monte Carlo Simulation method. Then, lognormal cumulative distribution function was used to represent the fragility. The results showed that windows located on the edge of leeward wall were more susceptible to wind load and the probability of failure for each window panel increased at higher floors.

Keywords: wind fragility, window system, high rise building, wind disaster

Procedia PDF Downloads 299
15887 Comparison of the Use of Vaccines or Drugs against Parasitic Diseases

Authors: H. Al-Khalaifa, A. Al-Nasser

Abstract:

The viewpoint towards the use of drugs or vaccines against avian parasitic diseases is one of the most striking challenges in avian medical parasitology. This includes many difficulties associated with drug resistance and in developing prophylactic vaccines. In many instances, the potential success of a vaccination in controlling parasitic diseases in poultry is well-documented. However, some medical, technical and financial limitations are still paramount. On the other hand, chemotherapy is not very well-recommended due to a number of medical limitations. But in the absence of an effective vaccine, drugs are used against parasitic diseases. This paper sheds light on some the advantages and disadvantages of using vaccination and drugs in controlling parasitic diseases in poultry species. The usage of chemotherapeutic drugs is discussed with some examples. Then, more light will be shed on using vaccines as a potentially effective and promising control tool.

Keywords: drugs, parasitology, poultry, vaccines

Procedia PDF Downloads 184
15886 Construction and Analysis of Samurai Sudoku

Authors: A. Danbaba

Abstract:

Samurai Sudoku consists of five Sudoku square designs each having nine treatments in each row (column or sub-block) only once such the five Sudoku designs overlaps. Two or more Samurai designs can be joint together to give an extended Samurai design. In addition, two Samurai designs, each containing five Sudoku square designs, are mutually orthogonal (Graeco). If we superimpose two Samurai designs and obtained a pair of Latin and Greek letters in each row (column or sub-block) of the five Sudoku designs only once, then we have Graeco Samurai design. In this paper, simple method of constructing Samurai designs and mutually orthogonal Samurai design are proposed. In addition, linear models and methods of data analysis for the designs are proposed.

Keywords: samurai design, graeco samurai design, sudoku design, row or column swap

Procedia PDF Downloads 257
15885 The Flexural Strength of Fiber-Reinforced Polymer Cement Mortars Using UM Resin

Authors: Min Ho Kwon, Woo Young Jung, Hyun Su Seo

Abstract:

A Polymer Cement Mortar (PCM) has been widely used as the material of repair and restoration work for concrete structure; however a PCM usually induces an environmental pollutant. Therefore, there is a need to develop PCM which is less impact to environments. Usually, UM resin is known to be harmless to the environment. Accordingly, in this paper, the properties of the PCM using UM resin were studied. The general cement mortar and UM resin was mixed in the specified ratio. A certain percentage of PVA fibers, steel fibers and mixed fibers (PVA fiber and steel fiber) were added to enhance the flexural strength. The flexural tests were performed in order to investigate the flexural strength of each PCM. Experimental results showed that the strength of proposed PCM using UM resin is improved when they are compared with general cement mortar.

Keywords: polymer cement mortar, UM resin, compressive strength, PVA fiber, steel fiber

Procedia PDF Downloads 330
15884 Numerical and Analytical Approach for Film Condensation on Different Forms of Surfaces

Authors: A. Kazemi Jouybari, A. Mirabdolah Lavasani

Abstract:

This paper seeks to the solution of condensation around of a flat plate, circular and elliptical tube in way of numerical and analytical methods. Also, it calculates the entropy production rates. The first, problem was solved by using mesh dynamic and rational assumptions, next it was compared with the numerical solution that the result had acceptable errors. An additional supporting relation was applied based on a characteristic of condensation phenomenon for condensing elements. As it has been shown here, due to higher rates of heat transfer for elliptical tubes, they have more entropy production rates, in comparison to circular ones. Findings showed that two methods were efficient. Furthermore, analytical methods can be used to optimize the problem and reduce the entropy production rate.

Keywords: condensation, numerical solution, analytical solution, entropy rate

Procedia PDF Downloads 201
15883 Biostimulation Effect of Ozone Therapy and Superficial Peeling on Facial Rejuvenation: A Case Report and Literature Review

Authors: Ferreira R., Rocha K.

Abstract:

Ozone therapy is indicated for improving skin aesthetics, adjusting oxidative tissue levels, increasing collagen production, and even skin volumizing. This paper aims to carry out a case report that demonstrates the positive results of ozone therapy in association with superficial peeling. The application in association showed positive results for bio-stimulating activities in the reported case demonstrating to be a viable clinical technique. The bio-stimulating effect of ozone therapy in association with peeling is a promising aesthetic therapeutic modality with fast and safe results as an aesthetic therapeutic option.

Keywords: bio-stimulating effect, ozone therapy, neocollagenesis, peeling

Procedia PDF Downloads 89
15882 Microwave Security System in Museums: Design and Implementation

Authors: Dalia Elsheakh, Hala Elsadek

Abstract:

The objective of this paper is to propose a competitive microwave security system that can be applied with reasonable price at museums in Egypt, considering the priceless elements in 23 Egyptian museums countrywide and the lack of good recent security systems even in big ones. The system main goal is to detect valuable targets to ensure their presence in the pre-defined positions in order to protect them from being stolen. The system is based on real time microwave scanning for the required space volume through transmitting RF waves at consecutive angles and detecting the back scattered waves from required objects to detect their existence at pre-specified locations.

Keywords: microwave security system, object locating system, real time locating system (RTLS), antenna array, array electronic scanning

Procedia PDF Downloads 331
15881 Gentrification and Its Impact on Urbanization in India

Authors: Swapnil Vidhate, Anupama Sharma

Abstract:

At present the world is experiencing an extraordinary rate of urbanization. India is also in a major phase of urbanization. Gentrification is being practiced in India much later compared to western countries as a strategy for urban renewal. The urban fabric in Indian context is composed of multiple layers in it. Thus, the process of gentrification has different typologies, views and impacts in Indian context. It is a curative concept to restructure the declined areas of the city. But it has more negative views compared to positive due to the concerns in the process in India. The paper brings out the impacts of gentrification and concerns related with the process in Indian context with a case example of core city.

Keywords: urbanization, urban renewal, gentrification, restructure, core city

Procedia PDF Downloads 722
15880 Cooperative CDD Scheme Based On Hierarchical Modulation in OFDM System

Authors: Seung-Jun Yu, Yeong-Seop Ahn, Young-Min Ko, Hyoung-Kyu Song

Abstract:

In order to achieve high data rate and increase the spectral efficiency, multiple input multiple output (MIMO) system has been proposed. However, multiple antennas are limited by size and cost. Therefore, recently developed cooperative diversity scheme, which profits the transmit diversity only with the existing hardware by constituting a virtual antenna array, can be a solution. However, most of the introduced cooperative techniques have a common fault of decreased transmission rate because the destination should receive the decodable compositions of symbols from the source and the relay. In this paper, we propose a cooperative cyclic delay diversity (CDD) scheme that uses hierarchical modulation. This scheme is free from the rate loss and allows seamless cooperative communication.

Keywords: MIMO, cooperative communication, CDD, hierarchical modulation

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15879 Modeling a Closed Loop Supply Chain with Continuous Price Decrease and Dynamic Deterministic Demand

Authors: H. R. Kamali, A. Sadegheih, M. A. Vahdat-Zad, H. Khademi-Zare

Abstract:

In this paper, a single product, multi-echelon, multi-period closed loop supply chain is surveyed, including a variety of costs, time conditions, and capacities, to plan and determine the values and time of the components procurement, production, distribution, recycling and disposal specially for high-tech products that undergo a decreasing production cost and sale price over time. For this purpose, the mathematic model of the problem that is a kind of mixed integer linear programming is presented, and it is finally proved that the problem belongs to the category of NP-hard problems.

Keywords: closed loop supply chain, continuous price decrease, NP-hard, planning

Procedia PDF Downloads 349
15878 Performance Analysis of ERA Using Fuzzy Logic in Wireless Sensor Network

Authors: Kamalpreet Kaur, Harjit Pal Singh, Vikas Khullar

Abstract:

In Wireless Sensor Network (WSN), the main limitation is generally inimitable energy consumption during processing of the sensor nodes. Cluster head (CH) election is one of the main issues that can reduce the energy consumption. Therefore, discovering energy saving routing protocol is the focused area for research. In this paper, fuzzy-based energy aware routing protocol is presented, which enhances the stability and network lifetime of the network. Fuzzy logic ensures the well-organized selection of CH by taking four linguistic variables that are concentration, energy, centrality, and distance to base station (BS). The results show that the proposed protocol shows better results in requisites of stability and throughput of the network.

Keywords: ERA, fuzzy logic, network model, WSN

Procedia PDF Downloads 259
15877 Impact of Reclamation on the Water Exchange in Bohai Bay

Authors: Luyao Liu, Dekui Yuan, Xu Li

Abstract:

As one of the most important bays of China, the water exchange capacity of Bohai Bay can influence the economic development and urbanization of surrounding cities. However, the rapid reclamation has influenced the weak water exchange capacity of this semi-enclosed bay in recent years. This paper sets two hydrodynamic models of Bohai Bay with two shorelines before and after reclamation. The mean value and distribution of Turn-over Time, the distribution of residual current, and the feature of the tracer path are compared. After comparison, it is found that Bohai Bay keeps these characteristics; the spending time of water exchange in the northern is longer than southern, and inshore is longer than offshore. However, the mean water exchange time becomes longer after reclamation. In addition, the material spreading is blocked because of the inwardly extending shorelines, and the direction changed from along the shoreline to towards the center after reclamation.

Keywords: Bohai Bay, water exchange, reclamation, turn-over time

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15876 Audio-Visual Entrainment and Acupressure Therapy for Insomnia

Authors: Mariya Yeldhos, G. Hema, Sowmya Narayanan, L. Dhiviyalakshmi

Abstract:

Insomnia is one of the most prevalent psychological disorders worldwide. Some of the deficiencies of the current treatments of insomnia are: side effects in the case of sleeping pills and high costs in the case of psychotherapeutic treatment. In this paper, we propose a device which provides a combination of audio visual entrainment and acupressure based compression therapy for insomnia. This device provides drug-free treatment of insomnia through a user friendly and portable device that enables relaxation of brain and muscles, with certain advantages such as low cost, and wide accessibility to a large number of people. Tools adapted towards the treatment of insomnia: -Audio -Continuous exposure to binaural beats of a particular frequency of audible range -Visual -Flash of LED light -Acupressure points -GB-20 -GV-16 -B-10

Keywords: insomnia, acupressure, entrainment, audio-visual entrainment

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15875 The Relevance of Smart Technologies in Learning

Authors: Rachael Olubukola Afolabi

Abstract:

Immersive technologies known as X Reality or Cross Reality that include virtual reality augmented reality, and mixed reality have pervaded into the education system at different levels from elementary school to adult learning. Instructors, instructional designers, and learning experience specialists continue to find new ways to engage students in the learning process using technology. While the progression of web technologies has enhanced digital learning experiences, analytics on learning outcomes continue to be explored to determine the relevance of these technologies in learning. Digital learning has evolved from web 1.0 (static) to 4.0 (dynamic and interactive), and this evolution of technologies has also advanced teaching methods and approaches. This paper explores how these technologies are being utilized in learning and the results that educators and learners have identified as effective learning opportunities and approaches.

Keywords: immersive technologoes, virtual reality, augmented reality, technology in learning

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15874 Comparison of Finite-Element and IEC Methods for Cable Thermal Analysis under Various Operating Environments

Authors: M. S. Baazzim, M. S. Al-Saud, M. A. El-Kady

Abstract:

In this paper, steady-state ampacity (current carrying capacity) evaluation of underground power cable system by using analytical and numerical methods for different conditions (depth of cable, spacing between phases, soil thermal resistivity, ambient temperature, wind speed), for two system voltage level were used 132 and 380 kV. The analytical method or traditional method that was used is based on the thermal analysis method developed by Neher-McGrath and further enhanced by International Electrotechnical Commission (IEC) and published in standard IEC 60287. The numerical method that was used is finite element method and it was recourse commercial software based on finite element method.

Keywords: cable ampacity, finite element method, underground cable, thermal rating

Procedia PDF Downloads 361
15873 Pattern Recognition Search: An Advancement Over Interpolation Search

Authors: Shahpar Yilmaz, Yasir Nadeem, Syed A. Mehdi

Abstract:

Searching for a record in a dataset is always a frequent task for any data structure-related application. Hence, a fast and efficient algorithm for the approach has its importance in yielding the quickest results and enhancing the overall productivity of the company. Interpolation search is one such technique used to search through a sorted set of elements. This paper proposes a new algorithm, an advancement over interpolation search for the application of search over a sorted array. Pattern Recognition Search or PR Search (PRS), like interpolation search, is a pattern-based divide and conquer algorithm whose objective is to reduce the sample size in order to quicken the process and it does so by treating the array as a perfect arithmetic progression series and thereby deducing the key element’s position. We look to highlight some of the key drawbacks of interpolation search, which are accounted for in the Pattern Recognition Search.

Keywords: array, complexity, index, sorting, space, time

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15872 Features Dimensionality Reduction and Multi-Dimensional Voice-Processing Program to Parkinson Disease Discrimination

Authors: Djamila Meghraoui, Bachir Boudraa, Thouraya Meksen, M.Boudraa

Abstract:

Parkinson's disease is a pathology that involves characteristic perturbations in patients’ voices. This paper describes a proposed method that aims to diagnose persons with Parkinson (PWP) by analyzing on line their voices signals. First, Thresholds signals alterations are determined by the Multi-Dimensional Voice Program (MDVP). Principal Analysis (PCA) is exploited to select the main voice principal componentsthat are significantly affected in a patient. The decision phase is realized by a Mul-tinomial Bayes (MNB) Classifier that categorizes an analyzed voice in one of the two resulting classes: healthy or PWP. The prediction accuracy achieved reaching 98.8% is very promising.

Keywords: Parkinson’s disease recognition, PCA, MDVP, multinomial Naive Bayes

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15871 Behaviours of Energy Spectrum at Low Reynolds Numbers in Grid Turbulence

Authors: Md Kamruzzaman, Lyazid Djenidi, R. A. Antonia

Abstract:

This paper reports an experimental investigation of the energy spectrum of turbulent velocity fields at low Reynolds numbers ( Rλ ) in grid turbulence. Hot wire measurements are carried out in grid turbulence with subjected to a 1.36:1 contraction of the wind tunnel. Three different grids are used: (i) large square perforated grid (mesh size 43.75 mm), (ii) small square perforated grid (mesh size 14 and (iii) woven mesh grid (mesh size 5mm). The results indicate that the energy spectrum at small Rλ does not follow Kolmogorov’s universal scaling. It is further found that the critical Reynolds number,Rλ,ϲ below which the scaling breaks down is around 25.

Keywords: energy spectrum, Taylor microscale, Reynolds number, turbulent kinetic energy, decay exponent

Procedia PDF Downloads 275
15870 Self-Tuning Robot Control Based on Subspace Identification

Authors: Mathias Marquardt, Peter Dünow, Sandra Baßler

Abstract:

The paper describes the use of subspace based identification methods for auto tuning of a state space control system. The plant is an unstable but self balancing transport robot. Because of the unstable character of the process it has to be identified from closed loop input-output data. Based on the identified model a state space controller combined with an observer is calculated. The subspace identification algorithm and the controller design procedure is combined to a auto tuning method. The capability of the approach was verified in a simulation experiments under different process conditions.

Keywords: auto tuning, balanced robot, closed loop identification, subspace identification

Procedia PDF Downloads 359
15869 Design and Analysis of Solar Powered Plane

Authors: Malarvizhi, Venkatesan

Abstract:

This paper summarizes about the design and optimization of solar powered unmanned aerial vehicle. The purpose of this research is to increase the range and endurance. It can be used for environmental research, aerial photography, search and rescue mission and surveillance in other planets. The ultimate aim of this research is to design and analyze the solar powered plane in order to detect lift, drag and other parameters by using cfd analysis. Similarly the numerical investigation has been done to compare the results of earth’s atmosphere to the mars atmosphere. This is the approach made to check whether the solar powered plane is possible to glide in the planet mars by using renewable energy (i.e., solar energy).

Keywords: optimization, range, endurance, surveillance, lift and drag parameters

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15868 The Second Column of Origen’s Hexapla and the Transcription of BGDKPT Consonants: A Confrontation with Transliterated Hebrew Names in Greek Documents

Authors: Isabella Maurizio

Abstract:

This research analyses the pronunciation of Hebrew consonants 'bgdkpt' in II- III C. E. in Palestine, through the confrontation of two kinds of data: the fragments of transliteration of Old Testament in the Greek alphabet, from the second column of Origen’s synopsis, called Hexapla, and Hebrew names transliterated in Greek documents, especially epigraphs. Origen is a very important author, not only for his bgdkpt theological and exegetic works: the Hexapla, synoptic six columns for a critical edition of Septuaginta, has a relevant role in attempting to reconstruct the pronunciation of Hebrew language before Masoretic punctuation. For this reason, at the beginning, it is important to analyze the column in order to study phonetic and linguistic phenomena. Among the most problematic data, there is the evidence from bgdkpt consonants, always represented as Greek aspirated graphemes. This transcription raised the question if their pronunciation was the only spirant, and consequently, the double one, that is, the stop/spirant contrast, was introduced by Masoretes. However, the phonetic and linguistic examination of the column alone is not enough to establish a real pronunciation of language: this paper is significant because a confrontation between the second column’s transliteration and Hebrew names found in Greek documents epigraphic ones mainly, is achieved. Palestine in II - III was a bilingual country: Greek and Aramaic language lived together, the first one like the official language, the second one as the principal mean of communication between people. For this reason, Hebrew names are often found in Greek documents of the same geographical area: a deep examination of bgdkpt’s transliteration can help to understand better which the real pronunciation of these consonants was, or at least it allows to evidence a phonetic tendency. As a consequence, the research considers the contemporary documents to Origen and the previous ones: the first ones testify a specific stadium of pronunciation, the second ones reflect phonemes’ evolution. Alexandrian documents are also examined: Origen was from there, and the influence of Greek language, spoken in his native country, must be considered. The epigraphs have another implication: they are totally free from morphological criteria, probably used by Origen in his column, because of their popular origin. Thus, a confrontation between the hexaplaric transliteration and Hebrew names is absolutely required, in Hexapla’s studies: first of all, it can be the second clue of a pronunciation already noted in the column; then because, for documents’ specific nature, it has more probabilities to be real, reflecting a daily use of language. The examination of data shows a general tendency to employ the aspirated graphemes for bgdkpt consonants’ transliteration. This probably means that they were closer to Greek aspirated consonants rather than to the plosive ones. The exceptions are linked to a particular status of the name, i.e. its history and origin. In this way, this paper gives its contribution to onomastic studies, too: indeed, the research may contribute to verify the diffusion and the treatment of Jewish names in Hellenized world and in the koinè language.

Keywords: bgdkpt consonants, Greek epigraphs, Jewish names, origen's Hexapla

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15867 Numerical Solution of 1-D Shallow Water Equations at Junction for Sub-Critical and Super-Critical Flow

Authors: Mohamed Elshobaki, Alessandro Valiani, Valerio Caleffi

Abstract:

In this paper, we solve 1-D shallow water equation for sub-critical and super-critical water flow at junction. The water flow at junction has been studied for the last 50 years from the physical-hydraulic point of views and for numerical computations need more attention. For numerical simulation, we need to establish an inner boundary condition at the junction to avoid an oscillation which rise from the waves interactions at the junction. Indeed, we introduce a new boundary condition at the junction based on the mass conservation, total head, and the admissible wave relations between the flow parameters in the three branches to predict the water depths and discharges at the junction. These boundary conditions are valid for sub-critical flow and super-critical flow.

Keywords: numerical simulation, junction flow, sub-critical flow, super-critical flow

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15866 Comparison of MODIS-Based Rice Extent Map and Landsat-Based Rice Classification Map in Determining Biomass Energy Potential of Rice Hull in Nueva Ecija, Philippines

Authors: Klathea Sevilla, Marjorie Remolador, Bryan Baltazar, Imee Saladaga, Loureal Camille Inocencio, Ma. Rosario Concepcion Ang

Abstract:

The underutilization of biomass resources in the Philippines, combined with its growing population and the rise in fossil fuel prices confirms demand for alternative energy sources. The goal of this paper is to provide a comparison of MODIS-based and Landsat-based agricultural land cover maps when used in the estimation of rice hull’s available energy potential. Biomass resource assessment was done using mathematical models and remote sensing techniques employed in a GIS platform.

Keywords: biomass, geographic information system (GIS), remote sensing, renewable energy

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15865 An Incremental Refinement Approach to a Development of Dynamic Host Configuration Protocol (DHCP) Using Event-B

Authors: Rajaa Filali, Mohamed Bouhdadi

Abstract:

This paper presents an incremental development of the Dynamic Host Configuration Protocol (DHCP) in Event-B. DHCP is widely used communication protocol, which provides a standard mechanism to obtain configuration parameters. The specification is performed in a stepwise manner and verified through a series of refinements. The Event-B formal method uses the Rodin platform to modeling and verifying some properties of the protocol such as safety, liveness and deadlock freedom. To model and verify the protocol, we use the formal technique Event-B which provides an accessible and rigorous development method. This interaction between modelling and proving reduces the complexity and helps to eliminate misunderstandings, inconsistencies, and specification gaps.

Keywords: DHCP protocol, Event-B, refinement, proof obligation, Rodin

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15864 Reliability Analysis of Partial Safety Factor Design Method for Slopes in Granular Soils

Authors: K. E. Daryani, H. Mohamad

Abstract:

Uncertainties in the geo-structure analysis and design have a significant impact on the safety of slopes. Traditionally, uncertainties in the geotechnical design are addressed by incorporating a conservative factor of safety in the analytical model. In this paper, a risk-based approach is adopted to assess the influence of the geotechnical variable uncertainties on the stability of infinite slopes in cohesionless soils using the “partial factor of safety on shear strength” approach as stated in Eurocode 7. Analyses conducted using Monte Carlo simulation show that the same partial factor can have very different levels of risk depending on the degree of uncertainty of the mean values of the soil friction angle and void ratio.

Keywords: Safety, Probability of Failure, Reliability, Infinite Slopes, Sand.

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15863 A United Nations Safety Compliant Urban Vehicle Design

Authors: Marcelo R. G. Duarte, Marcilio Alves

Abstract:

Pedestrians are the fourth group among road traffic users that most suffer accidents. Their death rate is even higher than the motorcyclists group. This gives motivation for the development of an urban vehicle capable of complying with the United Nations Economic Commission for Europe pedestrian regulations. The conceptual vehicle is capable of transporting two passengers and small parcels for 100 km at a maximum speed of 90 km/h. This paper presents the design of this vehicle using the finite element method specially in connection with frontal crash test and car to pedestrian collision. The simulation is based in a human body FE.

Keywords: electric urban vehicle, finite element method, global human body model, pedestrian safety, road safety

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15862 Comparative Exergy Analysis of Vapor Compression Refrigeration System Using Alternative Refrigerants

Authors: Gulshan Sachdeva, Vaibhav Jain

Abstract:

In present paper, the performance of various alternative refrigerants is compared to find the substitute of R22, the widely used hydrochlorofluorocarbon refrigerant in developing countries. These include the environmentally friendly hydrofluorocarbon (HFC) refrigerants such as R134A, R410A, R407C and M20. In the present study, a steady state thermodynamic model (includes both first and second law analysis) which simulates the working of an actual vapor-compression system is developed. The model predicts the performance of system with alternative refrigerants. Considering the recent trends of replacement of ozone depleting refrigerants and improvement in system efficiency, R407C is found to be potential candidate to replace R22 refrigerant in the present study.

Keywords: refrigeration, compression system, performance study, modeling, R407C

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15861 Adult Learners’ Code-Switching in the EFL Classroom: An Analysis of Frequency and Type of Code-Switching

Authors: Elizabeth Patricia Beck

Abstract:

Stepping into various English as foreign language classrooms, one will see some fundamental similarities. There will likely be groups of students working collaboratively, possibly sitting at tables together. They will be using a set coursebook or photocopies of materials developed by publishers or the teacher. The teacher will be carefully monitoring students’ behaviour and progress. The teacher will also likely be insisting that the students only speak English together, possibly having implemented a complex penalty and award systems to encourage this. This is communicative language teaching and it is commonly how foreign languages are taught around the world. Recently, there has been much interest in the codeswitching behaviour of learners in foreign or second language classrooms. It is a significant topic as it relates to second language acquisition theory, language teaching training and policy, and student expectations and classroom practice. Generally in an English as a foreign language context, an ‘English Only’ policy is the norm. This is based on historical factors, socio-political influence and theories surrounding language learning. The trend, however, is shifting and, based on these same factors, a re-examination of language use in the foreign language classroom is taking place. This paper reports the findings of an examination into the codeswitching behaviour of learners with a shared native language in an English classroom. Specifically, it addresses the question of classroom code-switching by adult learners in the EFL classroom during student-to-student, spoken interaction. Three generic categories of code switching are proposed based on published research and classroom practice. Italian adult learners at three levels were observed and patterns of language use were identified, recorded and analysed using the proposed categories. After observations were completed, a questionnaire was distributed to the students focussing on attitudes and opinions around language choice in the EFL classroom, specifically, the usefulness of L1 for specific functions in the classroom. The paper then investigates the relationship between learners’ foreign language proficiency and the frequency and type of code-switching that they engaged in, and the relationship between learners’ attitudes to classroom code-switching and their behaviour. Results show that code switching patterns underwent changes as the students’ level of English language proficiency improved, and that students’ attitudes towards code-switching generally correlated with their behaviour with some exceptions, however. Finally, the discussion focusses on the details of the language produced in observation, possible influencing factors that may affect the frequency and type of code switching that took place, and additional influencing factors that may affect students’ attitudes towards code switching in the foreign language classroom. An evaluation of the limitations of this study is offered and some suggestions are made for future research in this field of study.

Keywords: code-switching, EFL, second language aquisition, adult learners

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15860 The Review of Coiled Tubing Intelligent Sidetracking Steering Technology

Authors: Zhao Xueran, Yang Dong

Abstract:

In order to improve the problem that old wells in oilfields are shut down due to low oil recovery, sidetracking has become one of the main technical means to restore the vitality of old wells. A variety of sidetracking technologies have been researched and formed internationally. Among them, coiled tubing sidetracking horizontal wells have significant advantages over conventional sidetracking methods: underbalanced pressure operations; reducing the number of trips of tubing, while drilling and production, saving construction costs, less ground equipment and less floor space, orienter guidance to reduce drilling friction, etc. This paper mainly introduces the steering technology in coiled tubing intelligent sidetracking at home and abroad, including the orienter and the rotary steerable system.

Keywords: sidetracking, coiled tubing, orienter, rotary steering system

Procedia PDF Downloads 139
15859 Intelligent System for Diagnosis Heart Attack Using Neural Network

Authors: Oluwaponmile David Alao

Abstract:

Misdiagnosis has been the major problem in health sector. Heart attack has been one of diseases that have high level of misdiagnosis recorded on the part of physicians. In this paper, an intelligent system has been developed for diagnosis of heart attack in the health sector. Dataset of heart attack obtained from UCI repository has been used. This dataset is made up of thirteen attributes which are very vital in diagnosis of heart disease. The system is developed on the multilayer perceptron trained with back propagation neural network then simulated with feed forward neural network and a recognition rate of 87% was obtained which is a good result for diagnosis of heart attack in medical field.

Keywords: heart attack, artificial neural network, diagnosis, intelligent system

Procedia PDF Downloads 642