Search results for: double pipe heat exchangers
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4344

Search results for: double pipe heat exchangers

1884 Adapting Tools for Text Monitoring and for Scenario Analysis Related to the Field of Social Disasters

Authors: Svetlana Cojocaru, Mircea Petic, Inga Titchiev

Abstract:

Humanity faces more and more often with different social disasters, which in turn can generate new accidents and catastrophes. To mitigate their consequences, it is important to obtain early possible signals about the events which are or can occur and to prepare the corresponding scenarios that could be applied. Our research is focused on solving two problems in this domain: identifying signals related that an accident occurred or may occur and mitigation of some consequences of disasters. To solve the first problem, methods of selecting and processing texts from global network Internet are developed. Information in Romanian is of special interest for us. In order to obtain the mentioned tools, we should follow several steps, divided into preparatory stage and processing stage. Throughout the first stage, we manually collected over 724 news articles and classified them into 10 categories of social disasters. It constitutes more than 150 thousand words. Using this information, a controlled vocabulary of more than 300 keywords was elaborated, that will help in the process of classification and identification of the texts related to the field of social disasters. To solve the second problem, the formalism of Petri net has been used. We deal with the problem of inhabitants’ evacuation in useful time. The analysis methods such as reachability or coverability tree and invariants technique to determine dynamic properties of the modeled systems will be used. To perform a case study of properties of extended evacuation system by adding time, the analysis modules of PIPE such as Generalized Stochastic Petri Nets (GSPN) Analysis, Simulation, State Space Analysis, and Invariant Analysis have been used. These modules helped us to obtain the average number of persons situated in the rooms and the other quantitative properties and characteristics related to its dynamics.

Keywords: lexicon of disasters, modelling, Petri nets, text annotation, social disasters

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1883 Conservation of Sea Turtle in Cox’s Bazar- Teknaf Peninsula and Sonadia Island Ecologically Critical Area (ECA) of Bangladesh

Authors: Pronob Kumar Mozumder M. Nazrul Islam, M. Abdur Rob Mollah

Abstract:

This study was conducted in Cox’s Bazar-Teknaf Peninsula and Sonadia Island Ecologically Critical Areas during the period of October, 2011 to June, 2013. Six species of marine turtle are found in the Indian Ocean. Among them, olive ridley (Lepidochelys olivacea) listed as endangered in the IUCN Red List of Threatened Species. Marine turtle populations in the Indian Ocean have been depleted through long-term exploitation of eggs and adults, incidental capture (fisheries bycatch) and many other sources of mortality. The specific objective of the study was to conserve the sea turtles specially the olive ridley (Lepidochelys olivacea) with a view to contribute towards protection of the turtle species from extinction and to facilitate hatching of eggs through providing protection to turtle eggs or nest through ex-situ conservation efforts. In order to achieve the desired outputs and success, a total of five turtle hatcheries were established at Pechardwip, Khurermukh, Hazompara, Bodormokam, and Sonadia Eastpara sites. In total, 31,853 eggs were collected from 260 nests and were transferred to five hatcheries. The number of eggs/nest varied from 38 to 190 with an average clutch size of 122 eggs/ nest. Hatching of eggs took place during January to June with a peak in April. Sea turtle eggs were incubated by metabolic heat and the heat of the sun. The incubation period of turtle eggs in Cox’s Bazar-Teknaf Peninsula and Sonadia Island ECAs extended from 54 to 75 days depending on the month with an average of 66 days. During study period the temperature in the ECAs varied between 10.5-34.5°C. A total of 27,937 hatchlings of turtle were produced from the five hatcheries and all the hatchlings produced were released into the sea. Hatching rates varied from 74-98 % depending on the location and months with an average of 88 %. Sea turtles spend the majority of their lives in the sea, only emerging on beaches to nest. Despite the intense conservation efforts on the beaches, some populations have still declined to the edge of extinction. So proper conservation and awareness measure should be taken for prevention of turtle extinction.

Keywords: conservation of sea turtle, Bangladesh, ecologically critical area, ECA, Lepidochelys olivacea

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1882 Environmentally Adaptive Acoustic Echo Suppression for Barge-in Speech Recognition

Authors: Jong Han Joo, Jung Hoon Lee, Young Sun Kim, Jae Young Kang, Seung Ho Choi

Abstract:

In this study, we propose a novel technique for acoustic echo suppression (AES) during speech recognition under barge-in conditions. Conventional AES methods based on spectral subtraction apply fixed weights to the estimated echo path transfer function (EPTF) at the current signal segment and to the EPTF estimated until the previous time interval. We propose a new approach that adaptively updates weight parameters in response to abrupt changes in the acoustic environment due to background noises or double-talk. Furthermore, we devised a voice activity detector and an initial time-delay estimator for barge-in speech recognition in communication networks. The initial time delay is estimated using log-spectral distance measure, as well as cross-correlation coefficients. The experimental results show that the developed techniques can be successfully applied in barge-in speech recognition systems.

Keywords: acoustic echo suppression, barge-in, speech recognition, echo path transfer function, initial delay estimator, voice activity detector

Procedia PDF Downloads 354
1881 An Application of Sinc Function to Approximate Quadrature Integrals in Generalized Linear Mixed Models

Authors: Altaf H. Khan, Frank Stenger, Mohammed A. Hussein, Reaz A. Chaudhuri, Sameera Asif

Abstract:

This paper discusses a novel approach to approximate quadrature integrals that arise in the estimation of likelihood parameters for the generalized linear mixed models (GLMM) as well as Bayesian methodology also requires computation of multidimensional integrals with respect to the posterior distributions in which computation are not only tedious and cumbersome rather in some situations impossible to find solutions because of singularities, irregular domains, etc. An attempt has been made in this work to apply Sinc function based quadrature rules to approximate intractable integrals, as there are several advantages of using Sinc based methods, for example: order of convergence is exponential, works very well in the neighborhood of singularities, in general quite stable and provide high accurate and double precisions estimates. The Sinc function based approach seems to be utilized first time in statistical domain to our knowledge, and it's viability and future scopes have been discussed to apply in the estimation of parameters for GLMM models as well as some other statistical areas.

Keywords: generalized linear mixed model, likelihood parameters, qudarature, Sinc function

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1880 Protection of Human Rights in Europe: The Parliamentary Dimension

Authors: Aleksandra Chiniaeva

Abstract:

The following paper describes the activity of national and international parliamentary assemblies of the European region in protection and promotion of human rights. It may be said that parliamentarians have a “double mandate” — as members of the international assembly and of their respective national parliaments. In other words, parliamentarization at both international and national level provides a situation for parliamentarians, where they link people, national governments and international organizations. The paper is aimed towards demonstrating that the activity of the main international parliamentary assemblies of the European region have a real positive impact on the human rights situation in the European region. In addition, the paper describes the assemblies that include protection of human rights in their Agenda as one of the main subjects: the EP, the PACE, the OSCE PA and the IPA CIS. Co-operation activities such as joint election observation; participation in inter-parliamentary associations, such as the IPU; conclusion agreements allow assemblies to provide observation of human right situation in the states that are not members of the particular organization and as consequence make their impact broader.

Keywords: human rights, international parliamentary assembly, IPU, EP, PACE, OSCE, international election observation

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1879 “Double Layer” Theory of Hydrogenation

Authors: Vaclav Heral

Abstract:

Ideas about the mechanism of heterogeneous catalytic hydrogenation are diverse. The Horiuti-Polanyi mechanism is most often referred to, based on the idea of a semi-hydrogenated state. In our opinion, it does not represent a satisfactory explanation of the hydrogenation mechanism, because, for example: (1) It neglects the fact that the bond of atomic hydrogen to the metal surface is strongly polarized, (2) It does not explain why a surface deprived of atomic hydrogen (by thermal desorption or by alkyne) loses isomerization capabilities, but hydrogenation capabilities remain preserved, (3) It was observed that during the hydrogenation of 1-alkenes, the reaction can be of the 0th order to hydrogen and to the alkene at the same time, which is excluded during the competitive adsorption of both reactants on the catalyst surface. We offer an alternative mechanism that satisfactorily explains many of the ambiguities: It is the idea of an independent course of olefin isomerization, catalyzed by acidic atomic hydrogen bonded on the surface of the catalyst, in addition to the hydrogenation itself, in which a two-layer complex appears on the surface of the catalyst: olefin bound to the surface and molecular hydrogen bound to it in the second layer. The rate-determining step of hydrogenation is the conversion of this complex into the final product. We believe that the Horiuti-Polanyi mechanism is flawed and we naturally think that our two-layer theory better describes the experimental findings.

Keywords: acidity of hydrogenation catalyst, Horiuti-Polanyi, hydrogenation, two-layer hydrogenation

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1878 Triploid Rainbow Trout (Oncorhynchus mykiss) for Better Aquaculture and Ecological Risk Management

Authors: N. N. Pandey, Raghvendra Singh, Biju S. Kamlam, Bipin K. Vishwakarma, Preetam Kala

Abstract:

The rainbow trout (Oncorhynchus mykiss) is an exotic salmonid fish, well known for its fast growth, tremendous ability to thrive in diverse conditions, delicious flesh and hard fighting nature in Europe and other countries. Rainbow trout farming has a great potential for its contribution to the mainstream economy of Himalayan states in India and other temperate countries. These characteristics establish them as one of the most widely introduced and cultured fish across the globe, and its farming is also prominent in the cold water regions of India. Nevertheless, genetic fatigue, slow growth, early maturity, and low productivity are limiting the expansion of trout production. Moreover, farms adjacent to natural streams or other water sources are subject to escape of domesticated rainbow trout into the wild, which is a serious environmental concern as the escaped fish is subject to contaminate and disrupt the receiving ecosystem. A decline in production traits due to early maturity prolongs the culture duration and affects the profit margin of rainbow trout farms in India. A viable strategy that could overcome these farming constraints in large scale operation is the production of triploid fish that are sterile and more heterozygous. For better triploidy induction rate (TR), heat shock at 28°C for 10 minutes and pressure shock 9500 psi pressure for 5 minutes is applied to green eggs with 90-100% of triploidy success and 72-80% survival upto swim-up fry stage. There is 20% better growth in aquaculture with triploids rainbow trout over diploids. As compared to wild diploid fish, larger sized and fitter triploid rainbow trout in natural waters attract to trout anglers, and support the development of recreational fisheries by state fisheries departments without the risk of contaminating existing gene pools and disrupting local fish diversity. Overall, enhancement of productivity in rainbow trout farms and trout production in coldwater regions, development of lucrative trout angling and better ecological management is feasible with triploid rainbow trout.

Keywords: rainbow trout, triploids fish, heat shock, pressure shock, trout angling

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1877 High Temperature Volume Combustion Synthesis of Ti3Al with Low Porosities

Authors: Nese Ozturk Korpe, Muhammed H. Karas

Abstract:

Reaction synthesis, or combustion synthesis, is a processing technique in which the thermal activation energy of formation of a compound is sustained by its exothermic heat of reaction. The aim of the present study was to investigate the effect of high initial pressing pressures (420 MPa, 630 MPa, and 850 MPa) on porosity of Ti3Al which produced by volume combustion synthesis. Microstructure examinations were performed by optical microscope (OM) and scanning electron microscope (SEM). Phase analyses were performed with X-ray diffraction device (XRD). A significant decrease in porosity was obtained due to an increase in the initial pressing pressure.

Keywords: Titanium Aluminide, Volume Combustion Synthesis, Intermetallic, Porosity

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1876 Natural Convection between Two Parallel Wavy Plates

Authors: Si Abdallah Mayouf

Abstract:

In this work, the effects of the wavy surface on free convection heat transfer boundary layer flow between two parallel wavy plates have been studied numerically. The two plates are considered at a constant temperature. The equations and the boundary conditions are discretized by the finite difference scheme and solved numerically using the Gauss-Seidel algorithm. The important parameters in this problem are the amplitude of the wavy surfaces and the distance between the two wavy plates. Results are presented as velocity profiles, temperature profiles and local Nusselt number according to the important parameters.

Keywords: free convection, wavy surface, parallel plates, fluid dynamics

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1875 Optimizing Rectangular Microstrip Antenna Performance with Nanofiller Integration

Authors: Chejarla Raghunathababu, E. Logashanmugam

Abstract:

An antenna is an assortment of linked devices that function together to transmit and receive radio waves as a single antenna. Antennas occur in a variety of sizes and forms, but the microstrip patch antenna outperforms other types in terms of effectiveness and prediction. These antennas are easy to generate with discreet benefits. Nevertheless, the antenna's effectiveness will be affected because of the patch's shape above a thick dielectric substrate. As a result, a double-pole rectangular microstrip antenna with nanofillers was suggested in this study. By employing nano-composite substances (Fumed Silica and Aluminum Oxide), which are composites of graphene with nanofillers, the physical characteristics of the microstrip antenna, that is, the elevation of the microstrip antenna substrate and the width of the patch microstrip antenna have been improved in this research. The surface conductivity of graphene may be modified to function at specific frequencies. In order to prepare for future wireless communication technologies, a microstrip patch antenna operating at 93 GHz resonant frequency is constructed and investigated. The goal of this study was to reduce VSWR and increase gain. The simulation yielded results for the gain and VSWR, which were 8.26 dBi and 1.01, respectively.

Keywords: graphene, microstrip patch antenna, substrate material, wireless communication, nanocomposite material

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1874 Design of the Ice Rink of the Future

Authors: Carine Muster, Prina Howald Erika

Abstract:

Today's ice rinks are important energy consumers for the production and maintenance of ice. At the same time, users demand that the other rooms should be tempered or heated. The building complex must equally provide cooled and heated zones, which does not translate as carbon-zero ice rinks. The study provides an analysis of how the civil engineering sector can significantly impact minimizing greenhouse gas emissions and optimizing synergies across an entire ice rink complex. The analysis focused on three distinct aspects: the layout, including the volumetric layout of the premises present in an ice rink; the materials chosen that can potentially use the most ecological structural approach; and the construction methods based on innovative solutions to reduce carbon footprint. The first aspect shows that the organization of the interior volumes and defining the shape of the rink play a significant role. Its layout makes the use and operation of the premises as efficient as possible, thanks to the differentiation between heated and cooled volumes while optimising heat loss between the different rooms. The sprayed concrete method, which is still little known, proves that it is possible to achieve the strength of traditional concrete for the structural aspect of the load-bearing and non-load-bearing walls of the ice rink by using materials excavated from the construction site and providing a more ecological and sustainable solution. The installation of an empty sanitary space underneath the ice floor, making it independent of the rest of the structure, provides a natural insulating layer, preventing the transfer of cold to the rest of the structure and reducing energy losses. The addition of active pipes as part of the foundation of the ice floor, coupled with a suitable system, gives warmth in the winter and storage in the summer; this is all possible thanks to the natural heat in the ground. In conclusion, this study provides construction recommendations for future ice rinks with a significantly reduced energy demand, using some simple preliminary design concepts. By optimizing the layout, materials, and construction methods of ice rinks, the civil engineering sector can play a key role in reducing greenhouse gas emissions and promoting sustainability.

Keywords: climate change, energy optimization, green building, sustainability

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1873 3D Simulation of the Twin-Aperture IRON Superconducting Quadrupole for Charm-Tau Factory

Authors: K. K. Riabchenko, T. V Rybitskaya, A. A. Starostenko

Abstract:

Sper Charm-Tau Factory is a double ring e+e- collider to be operated in the center-of-mass energy range from 2 to 6 GeV, with a peak luminosity of about 1035 cm-2s-1 (Crab Waist collision) and with longitudinally polarized electrons at the IP (interaction point). One of the important elements of the cτ-factory is the superconducting two-aperture quadrupole of the final focus. It was decided to make a full-scale prototype quadrupole. The main objectives of our study included: 1) 3D modeling of the quadrupole in the Opera program, 2) Optimization of the geometry of the quadrupole lens, 3) Study of the influence of magnetic properties and geometry of a quadrupole on integral harmonics. In addition to this, the ways of producing unwanted harmonics have been studied. In the course of this work, a 3D model of a two-aperture iron superconducting quadrupole lens was created. A three-dimensional simulation of the magnetic field was performed, and the geometrical parameters of the lens were selected. Calculations helped to find sources of possible errors and methods for correcting unwanted harmonics. In addition to this, calculations show that there are no obstacles to the production of a prototype lens.

Keywords: super cτ-factory, final focus, twin aperture quadrupole lens, integral harmonics

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1872 Fabrication and Characterisation of Additive Manufactured Ti-6Al-4V Parts by Laser Powder Bed Fusion Technique

Authors: Norica Godja, Andreas Schindel, Luka Payrits, Zsolt Pasztor, Bálint Hegedüs, Petr Homola, Jan Horňas, Jiří Běhal, Roman Ruzek, Martin Holzleitner, Sascha Senck

Abstract:

In order to reduce fuel consumption and CO₂ emissions in the aviation sector, innovative solutions are being sought to reduce the weight of aircraft, including additive manufacturing (AM). Of particular importance are the excellent mechanical properties that are required for aircraft structures. Ti6Al4V alloys, with their high mechanical properties in relation to weight, can reduce the weight of aircraft structures compared to structures made of steel and aluminium. Currently, conventional processes such as casting and CNC machining are used to obtain the desired structures, resulting in high raw material removal, which in turn leads to higher costs and impacts the environment. Additive manufacturing (AM) offers advantages in terms of weight, lead time, design, and functionality and enables the realisation of alternative geometric shapes with high mechanical properties. However, there are currently technological shortcomings that have led to AM not being approved for structural components with high safety requirements. An assessment of damage tolerance for AM parts is required, and quality control needs to be improved. Pores and other defects cannot be completely avoided at present, but they should be kept to a minimum during manufacture. The mechanical properties of the manufactured parts can be further improved by various treatments. The influence of different treatment methods (heat treatment, CNC milling, electropolishing, chemical polishing) and operating parameters were investigated by scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX), X-ray diffraction (XRD), electron backscatter diffraction (EBSD) and measurements with a focused ion beam (FIB), taking into account surface roughness, possible anomalies in the chemical composition of the surface and possible cracks. The results of the characterisation of the constructed and treated samples are discussed and presented in this paper. These results were generated within the framework of the 3TANIUM project, which is financed by EU with the contract number 101007830.

Keywords: Ti6Al4V alloys, laser powder bed fusion, damage tolerance, heat treatment, electropolishing, potential cracking

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1871 Influence of Long-Term Variability in Atmospheric Parameters on Ocean State over the Head Bay of Bengal

Authors: Anindita Patra, Prasad K. Bhaskaran

Abstract:

The atmosphere-ocean is a dynamically linked system that influences the exchange of energy, mass, and gas at the air-sea interface. The exchange of energy takes place in the form of sensible heat, latent heat, and momentum commonly referred to as fluxes along the atmosphere-ocean boundary. The large scale features such as El Nino and Southern Oscillation (ENSO) is a classic example on the interaction mechanism that occurs along the air-sea interface that deals with the inter-annual variability of the Earth’s Climate System. Most importantly the ocean and atmosphere as a coupled system acts in tandem thereby maintaining the energy balance of the climate system, a manifestation of the coupled air-sea interaction process. The present work is an attempt to understand the long-term variability in atmospheric parameters (from surface to upper levels) and investigate their role in influencing the surface ocean variables. More specifically the influence of atmospheric circulation and its variability influencing the mean Sea Level Pressure (SLP) has been explored. The study reports on a critical examination of both ocean-atmosphere parameters during a monsoon season over the head Bay of Bengal region. A trend analysis has been carried out for several atmospheric parameters such as the air temperature, geo-potential height, and omega (vertical velocity) for different vertical levels in the atmosphere (from surface to the troposphere) covering a period from 1992 to 2012. The Reanalysis 2 dataset from the National Centers for Environmental Prediction-Department of Energy (NCEP-DOE) was used in this study. The study signifies that the variability in air temperature and omega corroborates with the variation noticed in geo-potential height. Further, the study advocates that for the lower atmosphere the geo-potential heights depict a typical east-west contrast exhibiting a zonal dipole behavior over the study domain. In addition, the study clearly brings to light that the variations over different levels in the atmosphere plays a pivotal role in supporting the observed dipole pattern as clearly evidenced from the trends in SLP, associated surface wind speed and significant wave height over the study domain.

Keywords: air temperature, geopotential height, head Bay of Bengal, long-term variability, NCEP reanalysis 2, omega, wind-waves

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1870 Thermal Buckling Response of Cylindrical Panels with Higher Order Shear Deformation Theory—a Case Study with Angle-Ply Laminations

Authors: Humayun R. H. Kabir

Abstract:

An analytical solution before used for static and free-vibration response has been extended for thermal buckling response on cylindrical panel with anti-symmetric laminations. The partial differential equations that govern kinematic behavior of shells produce five coupled differential equations. The basic displacement and rotational unknowns are similar to first order shear deformation theory---three displacement in spatial space, and two rotations about in-plane axes. No drilling degree of freedom is considered. Boundary conditions are considered as complete hinge in all edges so that the panel respond on thermal inductions. Two sets of double Fourier series are considered in the analytical solution process. The sets are selected that satisfy mixed type of natural boundary conditions. Numerical results are presented for the first 10 eigenvalues, and first 10 mode shapes for Ux, Uy, and Uz components. The numerical results are compared with a finite element based solution.

Keywords: higher order shear deformation, composite, thermal buckling, angle-ply laminations

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1869 Numerical Investigation of Wave Interaction with Double Vertical Slotted Walls

Authors: H. Ahmed, A. Schlenkhoff

Abstract:

Recently, permeable breakwaters have been suggested to overcome the disadvantages of fully protection breakwaters. These protection structures have minor impacts on the coastal environment and neighboring beaches where they provide a more economical protection from waves and currents. For regular waves, a numerical model is used (FLOW-3D, VOF) to investigate the hydraulic performance of a permeable breakwater. The model of permeable breakwater consists of a pair of identical vertical slotted walls with an impermeable upper and lower part, where the draft is a decimal multiple of the total depth. The middle part is permeable with a porosity of 50%. The second barrier is located at distant of 0.5 and 1.5 of the water depth from the first one. The numerical model is validated by comparisons with previous laboratory data and semi-analytical results of the same model. A good agreement between the numerical results and both laboratory data and semi-analytical results has been shown and the results indicate the applicability of the numerical model to reproduce most of the important features of the interaction. Through the numerical investigation, the friction factor of the model is carefully discussed.

Keywords: coastal structures, permeable breakwater, slotted wall, numerical model, energy dissipation coefficient

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1868 Simulation Study of Multiple-Thick Gas Electron Multiplier-Based Microdosimeters for Fast Neutron Measurements

Authors: Amir Moslehi, Gholamreza Raisali

Abstract:

Microdosimetric detectors based on multiple-thick gas electron multiplier (multiple-THGEM) configurations are being used in various fields of radiation protection and dosimetry. In the present work, microdosimetric response of these detectors to fast neutrons has been investigated by Monte Carlo method. Three similar microdosimeters made of A-150 and rexolite as the wall materials are designed; the first based on single-THGEM, the second based on double-THGEM and the third is based on triple-THGEM. Sensitive volume of the three microdosimeters is a right cylinder of 5 mm height and diameter which is filled with the propane-based tissue-equivalent (TE) gas. The TE gas with 0.11 atm pressure at the room temperature simulates 1 µm of tissue. Lineal energy distributions for several neutron energies from 10 keV to 14 MeV including 241Am-Be neutrons are calculated by the Geant4 simulation toolkit. Also, mean quality factor and dose-equivalent value for any neutron energy has been determined by these distributions. Obtained data derived from the three microdosimeters are in agreement. Therefore, we conclude that the multiple-THGEM structures present similar microdosimetric responses to fast neutrons.

Keywords: fast neutrons, geant4, multiple-thick gas electron multiplier, microdosimeter

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1867 Thermal Analysis of a Composite of Coco Fiber and Látex

Authors: Elmo Thiago Lins Cöuras Ford, Valentina Alessandra Carvalho do Vale

Abstract:

Given the unquestionable need of environmental preservation, the natural fibers have been seen as a salutary alternative for production of composites in substitution to the synthetic fibers, vitreous and metallic. In this work, the behavior of a composite was analyzed done with fiber of the peel of the coconut as reinforcement and latex as head office, when submitted the source of heat. The temperature profiles were verified in the internal surfaces and it expresses of the composite as well as the temperature gradient in the same. It was also analyzed the behavior of this composite when submitted to a cold source. As consequence, in function of the answers of the system, conclusions were reached.

Keywords: natural fiber, composite, temperature, latex, gradient

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1866 Opto-Thermal Frequency Modulation of Phase Change Micro-Electro-Mechanical Systems

Authors: Syed A. Bukhari, Ankur Goswmai, Dale Hume, Thomas Thundat

Abstract:

Here we demonstrate mechanical detection of photo-induced Insulator to metal transition (MIT) in ultra-thin vanadium dioxide (VO₂) micro strings by using < 100 µW of optical power. Highly focused laser beam heated the string locally resulting in through plane and along axial heat diffusion. Localized temperature increase can cause temperature rise > 60 ºC. The heated region of VO₂ can transform from insulating (monoclinic) to conducting (rutile) phase leading to lattice compressions and stiffness increase in the resonator. The mechanical frequency of the resonator can be tuned by changing optical power and wavelength. The first mode resonance frequency was tuned in three different ways. A decrease in frequency below a critical optical power, a large increase between 50-120 µW followed by a large decrease in frequency for optical powers greater than 120 µW. The dynamic mechanical response was studied as a function of incident optical power and gas pressure. The resonance frequency and amplitude of vibration were found to be decreased with increasing laser power from 25-38 µW and increased by1-2 % when the laser power was further increased to 52 µW. The transition in films was induced and detected by a single pump and probe source and by employing external optical sources of different wavelengths. This trend in dynamic parameters of the strings can be co-related with reversible Insulator to metal transition in VO₂ films which creates change in density of the material and hence the overall stiffness of the strings leading to changes in string dynamics. The increase in frequency at a particular optical power manifests a transition to a more ordered metallic phase which tensile stress onto the string. The decrease in frequency at higher optical powers can be correlated with poor phonon thermal conductivity of VO₂ in conducting phase. Poor thermal conductivity of VO₂ can force in-plane penetration of heat causing the underneath SiN supporting VO₂ which can result as a decrease in resonance frequency. This noninvasive, non-contact laser-based excitation and detection of Insulator to metal transition using micro strings resonators at room temperature and with laser power in few µWs is important for low power electronics, and optical switching applications.

Keywords: thermal conductivity, vanadium dioxide, MEMS, frequency tuning

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1865 Temperature Investigations in Two Type of Crimped Connection Using Experimental Determinations

Authors: C. F. Ocoleanu, A. I. Dolan, G. Cividjian, S. Teodorescu

Abstract:

In this paper we make a temperature investigations in two type of superposed crimped connections using experimental determinations. All the samples use 8 copper wire 7.1 x 3 mm2 crimped by two methods: the first method uses one crimp indents and the second is a proposed method with two crimp indents. The ferrule is a parallel one. We study the influence of number and position of crimp indents. The samples are heated in A.C. current at different current values until steady state heating regime. After obtaining of temperature values, we compare them and present the conclusion.

Keywords: crimped connections, experimental determinations, temperature, heat transfer

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1864 A Biologically Inspired Approach to Automatic Classification of Textile Fabric Prints Based On Both Texture and Colour Information

Authors: Babar Khan, Wang Zhijie

Abstract:

Machine Vision has been playing a significant role in Industrial Automation, to imitate the wide variety of human functions, providing improved safety, reduced labour cost, the elimination of human error and/or subjective judgments, and the creation of timely statistical product data. Despite the intensive research, there have not been any attempts to classify fabric prints based on printed texture and colour, most of the researches so far encompasses only black and white or grey scale images. We proposed a biologically inspired processing architecture to classify fabrics w.r.t. the fabric print texture and colour. We created a texture descriptor based on the HMAX model for machine vision, and incorporated colour descriptor based on opponent colour channels simulating the single opponent and double opponent neuronal function of the brain. We found that our algorithm not only outperformed the original HMAX algorithm on classification of fabric print texture and colour, but we also achieved a recognition accuracy of 85-100% on different colour and different texture fabric.

Keywords: automatic classification, texture descriptor, colour descriptor, opponent colour channel

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1863 Cogeneration Unit for Small Stove

Authors: Michal Spilacek, Marian Brazdil, Otakar Stelcl, Jiri Pospisil

Abstract:

This paper shows an experimental testing of a small unit for combustion of solid fuels, such as charcoal and wood logs, that can provide electricity. One of the concepts is that the unit does not require a qualified personnel for its operation. The unit itself is composed of two main parts. The design requires a heat producing stove and an electricity producing thermoelectric generator. After the construction the unit was tested and the results shows that the emission release is within the legislative requirements for emission production and environmental protection. That qualifies such unit for indoor application.

Keywords: micro-cogeneration, thermoelectric generator, biomass combustion, wood stove

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1862 Water Quality, Risk, Management and Distribution in Abeokuta, Ogun State

Authors: Ayedun Hassan, Ayadi Odunayo Peter

Abstract:

The ancient city of Abeokuta has been supplied with pipe borne water since 1911, yet, a continuous increase in population and unplanned city expansion makes water a very precious and scarce commodity. The government reserved areas (GRA’s) are well planned, and public water supply is available; however, the sub-urban areas consist of scattered structures with individuals trying to source water by digging wells and boreholes. The geology of the city consists of basement rock which makes digging wells and boreholes very difficult. The present study was conducted to assess the risk arising from the consumption of toxic elements in the groundwater of Abeokuta, Ogun State, Nigeria. Forty-five groundwater samples were collected from nine different areas of Abeokuta and analyzed for physicochemical parameters and toxic elements. The physicochemical parameters were determined using standard methods, while the toxic elements were determined using Inductively Coupled Plasma-Mass Spectrometer (ICP/MS). Ninety-six percent (96%) of the water sample has pH < 6.5, and 11% has conductivity > 250 µSCm⁻¹ limits in drinking water as recommended by WHO. Seven percent (7%) of the samples have Pb concentration >10 µgL⁻¹ while 75% have Al concentration >200 µgL⁻¹ recommended by WHO. The order for risk of cancer from different area of Abeokuta are Cd²⁺ > As³⁺ > Pb²⁺ > Cr⁶⁺ for Funaab, Camp and Obantoko; As³⁺ > Cd²⁺ > Pb²⁺ > Cr⁶⁺ for Ita Osin, Isale Igbein, Ake and Itoku; Cd²⁺ >As > Cr⁶⁺ > Pb²⁺ for Totoro; Pb²⁺ > Cd²⁺ > As³⁺ > Cr⁶⁺ for Idiaba. The order of non-cancer hazard index (HI) calculated for groundwater of Abeokuta City are Cd²⁺ > As³⁺ > Mn²⁺ > Pb²⁺ > Ni²⁺ and were all greater than one, which implies susceptibility to other illnesses. The sources of these elements are the rock and inappropriate waste disposal method, which leached the elements into the groundwater. A combination of sources from food will accumulate these elements in the human body system. Treatment to remove Al and Pb is necessary, while the method of water distribution should be reviewed to ensure access to potable water by the residents.

Keywords: Abeokuta, groundwater, Nigeria, risk

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1861 Mutagenicity Evaluation of Locally Produced Biphasic Calcium Phosphate Using Ames Test

Authors: Nur Fathin Alia Che Wahab, Thirumulu Ponnuraj Kannan, Zuliani Mahmood, Ismail Ab. Rahman, Hanafi Ismail

Abstract:

Locally produced Biphasic Calcium Phosphate (BCP) consists of hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) which is a promising material for dentin and bone regeneration as well as in tissue engineering applications. The study was carried out to investigate the mutagenic effect of locally produced BCP using Ames test. Mutagenicity was evaluated with and without the addition of metabolic activation system (S9). This study was performed on Salmonella typhimurium TA98, TA102, TA1537, and TA1538 strains using preincubation assay method. The doses tested were 5000, 2500, 1250, 625, 313 µg/plate. Negative and positive controls were also included. The bacteria were incubated for 48 hours at 37 ± 0.5 °C. Then, the revertant colonies were counted. Data obtained were evaluated using non-statistical method. The mean number of revertant colonies in strains with and without S9 mix treated with locally produced BCP was less than double when compared to negative control for all the tested concentrations. The results from this study indicate that the locally produced BCP is non-mutagenic under the present test conditions.

Keywords: ames test, biphasic calcium phosphate, dentin regeneration, mutagenicity

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1860 Heroin Withdrawal, Prison and Multiple Temporalities

Authors: Ian Walmsley

Abstract:

The aim of this paper is to explore the influence of time and temporality on the experience of coming off heroin in prison. The presentation draws on qualitative data collected during a small-scale pilot study of the role of self-care in the process of coming off drugs in prison. Time and temporality emerged as a key theme in the interview transcripts. Drug dependent prisoners experience of time in prison has not been recognized in the research literature. Instead, the literature on prison time typically views prisoners as a homogenous group or tends to focus on the influence of aging and gender on prison time. Furthermore, there is a tendency in the literature on prison drug treatment and recovery to conceptualize drug dependent prisoners as passive recipients of prison healthcare, rather than active agents. In building on these gaps, this paper argues that drug dependent prisoners experience multiple temporalities which involve an interaction between the body-times of the drug dependent prisoner and the economy of time in prison. One consequence of this interaction is the feeling that they are doing, at this point in their prison sentence, double prison time. The second part of the argument is that time and temporality were a means through which they governed their withdrawing bodies. In addition, this paper will comment on the challenges of prison research in England.

Keywords: heroin withdrawal, time and temporality, prison, body

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1859 Effects of Oral Resveratrol Supplementation on Inflammation and Quality of Life in Patients with Ulcerative Colitis

Authors: M. Samsami, A. Hekmatdoost, N. Ebrahimi Daryani, P. Rezanejad Asl

Abstract:

Ulcerative colitis (UC) is an inflammatory bowel disease in which immune and inflammatory factors are thought to be effective in this disease. Resveratrol is an antioxidant and anti-inflammatory compound. This study determined the effects of resveratrol compound on inflammatory factors in patients with ulcerative colitis. This study was a double-blind randomized clinical trial conducted on 50 patients with UC. Subjects received one capsule daily for 6 wk of either resveratrol (500 mg) or a placebo. Inflammatory factors, anthropometric measures, and IBDQ-9 (Inflammatory Bowel Disease Questionnaire-9) scores were assessed at baseline and at the end of the study. STATA12 software was used for data analysis. No significant differences were found in the background variables between the two groups at baseline. The results indicated that resveratrol supplementation for 6 week significantly decreased plasma levels of TNF-a and hs-CRP and the activity of NF-κB over the placebo group (p<0.001). Significant differences remained after adjustment for vitamin C (p<0.0001). The IBDQ-9 scores increased significantly in the resveratrol group over the placebo group (p<0.001). The findings of this study showed that resveratrol supplementation can be useful in patients with ulcerative colitis.

Keywords: IBD, inflammation, resveratrol, ulcerative colitis

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1858 'Sextually' Active: Teens, 'Sexting' and Gendered Double Standards in the Digital Age

Authors: Annalise Weckesser, Alex Wade, Clara Joergensen, Jerome Turner

Abstract:

Introduction: Digital mobile technologies afford Generation M a number of opportunities in terms of communication, creativity and connectivity in their social interactions. Yet these young people’s use of such technologies is often the source of moral panic with accordant social anxiety especially prevalent in media representations of teen ‘sexting,’ or the sending of sexually explicit images via smartphones. Thus far, most responses to youth sexting have largely been ineffective or unjust with adult authorities sometimes blaming victims of non-consensual sexting, using child pornography laws to paradoxically criminalise those they are designed to protect, and/or advising teenagers to simply abstain from the practice. Prevention strategies are further skewed, with sex education initiatives often targeted at girls, implying that they shoulder the responsibility of minimising the risks associated with sexting (e.g. revenge porn and sexual predation). Purpose of Study: Despite increasing public interest and concern about ‘teen sexting,’ there remains a dearth of research with young people regarding their experiences of navigating sex and relationships in the current digital media landscape. Furthermore, young people's views on sexting are rarely solicited in the policy and educational strategies aimed at them. To address this research-policy-education gap, an interdisciplinary team of four researchers (from anthropology, media, sociology and education) have undertaken a peer-to-peer research project to co-create a sexual health intervention. Methods: In the winter of 2015-2016, the research team conducted serial group interviews with four cohorts of students (aged 13 to 15) from a secondary school in the West Midlands, UK. To facilitate open dialogue, girls and boys were interviewed separately, and each group consisted of no more than four pupils. The team employed a range of participatory techniques to elicit young people’s views on sexting, its consequences, and its interventions. A final focus group session was conducted with all 14 male and female participants to explore developing a peer-to-peer ‘safe sexting’ education intervention. Findings: This presentation will highlight the ongoing, ‘old school’ sexual double standards at work within this new digital frontier. In the sharing of ‘nudes’ (teens’ preferred term to ‘sexting’) via social media apps (e.g. Snapchat and WhatsApp), girls felt sharing images was inherently risky and feared being blamed and ‘slut-shamed.’ In contrast, boys were seen to gain in social status if they accumulated nudes of female peers. Further, if boys had nudes of themselves shared without consent, they felt they were expected to simply ‘tough it out.’ The presentation will also explore what forms of supports teens desire to help them in their day-to-day navigation of these digitally mediated, heteronormative performances of teen femininity and masculinity expected of them. Conclusion: This is the first research project, within UK, conducted with rather than about teens and the phenomenon of sexting. It marks a timely and important contribution to the nascent, but growing body of knowledge on gender, sexual politics and the digital mobility of sexual images created by and circulated amongst young people.

Keywords: teens, sexting, gender, sexual politics

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1857 Growth of SWNTs from Alloy Catalyst Nanoparticles

Authors: S. Forel, F. Bouanis, L. Catala, I. Florea, V. Huc, F. Fossard, A. Loiseau, C. Cojocaru

Abstract:

Single wall carbon nanotubes are seen as excellent candidate for application on nanoelectronic devices because of their remarkable electronic and mechanical properties. These unique properties are highly dependent on their chiral structures and the diameter. Therefore, structure controlled growth of SWNTs, especially directly on final device’s substrate surface, are highly desired for the fabrication of SWNT-based electronics. In this work, we present a new approach to control the diameter of SWNTs and eventually their chirality. Because of their potential to control the SWNT’s chirality, bi-metalics nanoparticles are used to prepare alloy nanoclusters with specific structure. The catalyst nanoparticles are pre-formed following a previously described process. Briefly, the oxide surface is first covered with a SAM (self-assembled monolayer) of a pyridine-functionalized silane. Then, bi-metallic (Fe-Ru, Co-Ru and Ni-Ru) complexes are assembled by coordination bonds on the pre-formed organic SAM. The resultant alloy nanoclusters were then used to catalyze SWNTs growth on SiO2/Si substrates via CH4/H2 double hot-filament chemical vapor deposition (d-HFCVD). The microscopy and spectroscopy analysis demonstrate the high quality of SWNTs that were furthermore integrated into high-quality SWNT-FET.

Keywords: nanotube, CVD, device, transistor

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1856 Violence and Aggression of Women in Native Canada: A Postcolonial Feminist Study of The Rez Sisters and Rose by Tomson Highway

Authors: Sonia Sharma

Abstract:

In a multicultural country like Canada, Colonialism is still maintained in the form of Violence and Oppression. The Aboriginals are persistently facing Oppression and Marginalization in their own land owing to Colonial presence. Women in particular are getting most affected. They are facing double burden of patriarchy and their being Native. Tomson Highway, the Cree Canadian playwright has deftly exposed the theme of women violence and empowerment. In his plays (The Rez Sisters and Rose) taken from his Rez Septology, he has depicted Aboriginal women’s predicaments and sufferings. But simultaneously also talks about their empowerment and aggression refuting and fighting back to patriarchy and oppression. The Rez Sisters portrays women with shattering images and as a victim of both the male dominating society and the system. It represents the painful odyssey of the seven women facing several hardships. Rose represents women in entirely different light. They are shown more assertive and empowered raising their voice against the Violence and Discrimination meted out to them. The Aboriginal women in Canada are facing dual burden of Colonialism and Patriarchy which indeed is a Colonial construct. This paper is an attempt to explore the above facets Tomson Highway’s The Rez Sisters and Rose.

Keywords: violence, racism, discrimination, postcolonialism feminism

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1855 The Effect of Using Water Wireless Aqua Com System on the Development of Dolphin Kick Movements on the Female Swimming Team at the Faculty of Physical Education

Authors: Wisal Alrabadi

Abstract:

The study's goal was to see how the use of water wireless Aqua Com System and its accompanying music affected the Female Swimming Team at the Faculty of Physical Education's development of dolphin kick movements. To that end, a training program consisting of (12) training units spread out over four weeks, three units per week, was created and applied to a study sample of (10) students from the swimming pool enrolled in the first semester of the academic year 2022. Pre-measuring and timing the movements of dolphins kicking with and without fins above and below, measuring the water's surface over a distance of 25 meters. The results showed that there are statistically significant differences in favor of telemetry from the start within the limits of the area specified for a distance of 15 m after the comparison between the pre and post-measurement using the test (T) of the double samples, and this indicates the impact of the training program using the Aqua Com System in the swimming team(Female) at Faculty of Physical Education, and in light of this a set of recommendations was developed.

Keywords: aqua com system training program, accompanying music, dolphin kick movements, swimming team female

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