Search results for: surface displacement history
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9845

Search results for: surface displacement history

7565 Wettability of Superhydrophobic Polymer Layers Filled with Hydrophobized Silica on Glass

Authors: Diana Rymuszka, Konrad Terpiłowski, Lucyna Hołysz, Elena Goncharuk, Iryna Sulym

Abstract:

Superhydrophobic surfaces exhibit extremely high water repellency. The commonly accepted basic criterion for such surfaces is a water contact angle larger than 150°, low contact angle hysteresis and low sliding angle. These surfaces are of special interest, because properties such as anti-sticking, anti-contamination and self-cleaning are expected. These properties are attractive for many applications such as anti-sticking of snow for antennas and windows, anti-biofouling paints for boats, waterproof clothing, self-cleaning windshields for automobiles, dust-free coatings or metal refining. The various methods for the preparation of superhydrophobic surfaces since last two decades have been reported, such as phase separation, electrochemical deposition, template method, plasma method, chemical vapor deposition, wet chemical reaction, sol-gel processing, lithography and so on. The aim of the study was to investigate the influence of modified colloidal silica, used as a filler, on the hydrophobicity of the polymer film deposited on the glass support activated with plasma. On prepared surfaces water advancing (ӨA) and receding (ӨR) contact angles were measured and then their total apparent surface free energy was determined using the contact angle hysteresis approach (CAH). The structures of deposited films were observed with the help of an optical microscope. Topographies of selected films were also determined using an optical profilometer. It was found that plasma treatment influence glass surface wetting and energetic properties that is observed in higher adhesion between polymer/filler film and glass support. Using the colloidal silica particles as a filler for the polymer thin film deposited on the glass support, it is possible to produce strongly adhering layers of superhydrophobic properties. The best superhydrophobic properties were obtained for surfaces of the film glass/polimer + modified silica covered in 89 and 100%. The advancing contact angle measured on these surfaces amounts above 150° that leads to under 2 mJ/m2 value of the apparent surface free energy. Such films may have many practical applications, among others, as dust-free coatings or anticorrosion protection.

Keywords: contact angle, plasma, superhydrophobic, surface free energy

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7564 Behavior of Printing Inks on Historical Documents Subjected to Cold RF Plasma Discharges

Authors: Dorina Rusu, Emil Ghiocel Ioanid, Marta Ursescu, Ana Maria Vlad, Mihaela Popescu

Abstract:

During the last decades the cold plasma discharges made the subject of numerous studies concerning the applications in the cultural heritage field, especially concentrated on ecological and non-invasive aspect of these conservation procedures. The conservation treatment using cold plasma is based, on the one hand, on the well-known property of plasma discharges to inactivate the contaminant biological species and, on the other hand, on the surface cleaning effect. Moreover the plasma discharge produces the functionalization of the treated surface, allowing subsequent deposition of protective layers. The paper presents the behavior of printing inks on historical documents treated in cold RF plasma. Two types of printing inks were studied, namely red and black ink, used on a religious book published in 19 century. SEM-EDX analysis results in the identification of the two inks as carbon black ink (C presence in the EDX spectrum) and cinnabar based red ink (Hg and S lines in the spectrum), result confirmed by XRF analysis. The experiments have been performed on paper samples written with laboratory- made inks, of similar composition with the inks identified on historical documents. The samples were subjected to RF plasma discharge, operating in nitrogen gaseous medium, at 1.2 MHz frequency and low-pressure (0.5 mbar), performed in a self-designed equipment for the application of conservation treatments on naturally aged paper supports. The impact of plasma discharge on the inks has been evaluated by SEM, XRD and color analysis. The color analysis revealed a slight discoloration of cinnabar ink on the historical document. SEM and XRD analyses have been carried out in an attempt to elucidate the process responsable for color modification.

Keywords: RF plasma, printing inks, historical documents, surface cleaning effect

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7563 Self-Propelled Intelligent Robotic Vehicle Based on Octahedral Dodekapod to Move in Active Branched Pipelines with Variable Cross-Sections

Authors: Sergey N. Sayapin, Anatoly P. Karpenko, Suan H. Dang

Abstract:

Comparative analysis of robotic vehicles for pipe inspection is presented in this paper. The promising concept of self-propelled intelligent robotic vehicle (SPIRV) based on octahedral dodekapod for inspection and operation in active branched pipelines with variable cross-sections is reasoned. SPIRV is able to move in pipeline, regardless of its spatial orientation. SPIRV can also be used to move along the outside of the pipelines as well as in space between surfaces of annular tubes. Every one of faces of the octahedral dodekapod can clamp/unclamp a thing with a closed loop surface of various forms as well as put pressure on environmental surface of contact. These properties open new possibilities for its applications in SPIRV. We examine design principles of octahedral dodekapod as future intelligent building blocks for various robotic vehicles that can self-move and self-reconfigure.

Keywords: Modular robot, octahedral dodekapod, pipe inspection robot, spatial parallel structure

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7562 Optimum Design of Grillage Systems Using Firefly Algorithm Optimization Method

Authors: F. Erdal, E. Dogan, F. E. Uz

Abstract:

In this study, firefly optimization based optimum design algorithm is presented for the grillage systems. Naming of the algorithm is derived from the fireflies, whose sense of movement is taken as a model in the development of the algorithm. Fireflies’ being unisex and attraction between each other constitute the basis of the algorithm. The design algorithm considers the displacement and strength constraints which are implemented from LRFD-AISC (Load and Resistance Factor Design-American Institute of Steel Construction). It selects the appropriate W (Wide Flange)-sections for the transverse and longitudinal beams of the grillage system among 272 discrete W-section designations given in LRFD-AISC so that the design limitations described in LRFD are satisfied and the weight of the system is confined to be minimal. Number of design examples is considered to demonstrate the efficiency of the algorithm presented.

Keywords: firefly algorithm, steel grillage systems, optimum design, stochastic search techniques

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7561 The Genre Narrative in Beethoven's E-Flat Piano Sonata, Op.31/3

Authors: Yan Zou

Abstract:

Approach to the theory of Musical Narrative, as well as the three criteria of the 'explicit narrative', 'potential narrative' and 'image narrative' which are used to analyze the music, the author put Beethoven’s Piano Sonata in E-flat major, Op.31/3, into the context of the music genre and Western music history, and interpreted the programmatic contents that were embodied and hid in the special music genres.

Keywords: analysis, genre, narrative, rhetoric

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7560 Prediction Modeling of Compression Properties of a Knitted Sportswear Fabric Using Response Surface Method

Authors: Jawairia Umar, Tanveer Hussain, Zulfiqar Ali, Muhammad Maqsood

Abstract:

Different knitted structures and knitted parameters play a vital role in the stretch and recovery management of compression sportswear in addition to the materials use to generate this stretch and recovery behavior of the fabric. The present work was planned to predict the different performance indicators of a compression sportswear fabric with some ground parameters i.e. base yarn stitch length (polyester as base yarn and spandex as plating yarn involve to make a compression fabric) and linear density of the spandex which is a key material of any sportswear fabric. The prediction models were generated by response surface method for performance indicators such as stretch & recovery percentage, compression generated by the garment on body, total elongation on application of high power force and load generated on certain percentage extension in fabric. Certain physical properties of the fabric were also modeled using these two parameters.

Keywords: Compression, sportswear, stretch and recovery, statistical model, kikuhime

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7559 The Early Discovery and Confirmation of the Indus Valley Civilization

Authors: Muhammad Ishaqa, Quanchao Zhanga, Qian Wangb

Abstract:

The Indus Valley Civilization is predominantly found in the northeast of Afghanistan, Pakistan, and the northwest of India and is considered one of the four ancient civilizations of the Old World, as well as the first urban civilization in South Asia. In 1920, John Marshall and other archaeologists established the existence of this civilization. Over the course of a century, India and Pakistan have made significant advancements in their joint archaeological investigation and excavation, contributing to the study of the Indus Valley Civilization. Given the importance of early discovery and confirmation of this civilization, our research focuses on the academic history of its archaeology by gathering published research material. Our research begins by collecting research data associated with the Indus Valley Civilization and documenting the process of archaeological investigations and excavations from the 19th century until the present day. We also summarize the archaeological works conducted during different periods. Furthermore, we present the primary academic views on the Indus Civilization from the 19th century until the present, explaining their developmental process and highlighting recent research. This forms a foundation for further study. We discovered that the archaeological research of the Indus Civilization is significantly influenced by Western archaeology and has yet to establish an independent, local research system. We delve into the three primary sites of the Indus Valley Civilization - Harappa, Mohenjo-Daro, and Chanhudaro - discussing their history and archaeological excavation records. Our findings indicate that the Indus Civilization is solely dependent on archaeology, distinguishing it from the Sumerian Civilization and verifying that it originates from the Bronze Age of the Indus Valley. Lastly, we examine the primary academic issues associated with the Indus Civilization in greater depth. These issues include climate environment, political system, primitive religion, and academic contribution.

Keywords: Indus Valley civilization, archaeology, Harappa, Mohenjo-Daro

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7558 Precursor Muscle Cell’s Phenotype under Compression in a Biomimetic Mechanical Niche

Authors: Fatemeh Abbasi, Arne Hofemeier, Timo Betz

Abstract:

Muscle growth and regeneration critically depend on satellite cells (SCs) which are muscle stem cells located between the basal lamina and myofibres. Upon damage, SCs become activated, enter the cell cycle, and give rise to myoblasts that form new myofibres, while a sub-population self-renew and re-populate the muscle stem cell niche. In aged muscle as well as in certain muscle diseases such as muscular dystrophy, some of the SCs lose their regenerative ability. Although it is demonstrated that the chemical composition of SCs quiescent niche is different from the activated niche, the mechanism initially activated in the SCs remains unknown. While extensive research efforts focused on potential chemical activation, no such factor has been identified to the author’s best knowledge. However, it is substantiated that niche mechanics affects SCs behaviors, such as stemness and engraftment. We hypothesize that mechanical stress in the healthy niche (homeostasis) is different from the regenerative niche and that this difference could serve as an early signal activating SCs upon fiber damage. To investigate this hypothesis, we develop a biomimetic system to reconstitute both, the mechanical and the chemical environment of the SC niche. Cells will be confined between two elastic polyacrylamide (PAA) hydrogels with controlled elastic moduli and functionalized surface chemistry. By controlling the distance between the PAA hydrogel surfaces, we vary the compression forces exerted by the substrates on the cells, while the lateral displacement of the upper hydrogel will create controlled shear forces. To establish such a system, a simplified system is presented. We engineered a sandwich-like configuration of two elastic PAA layer with stiffnesses between 1 and 10 kPa and confined a precursor myoblast cell line (C2C12) in between these layers. Our initial observations in this sandwich model indicate that C2C12 cells show different behaviors under mechanical compression if compared to a control one-layer gel without compression. Interestingly, this behavior is stiffness-dependent. While the shape of C2C12 cells in the sandwich consisting of two stiff (10 kPa) layers was much more elongated, showing almost a neuronal phenotype, the cell shape in a sandwich situation consisting of one stiff and one soft (1 kPa) layer was more spherical. Surprisingly, even in proliferation medium and at very low cell density, the sandwich situation stimulated cell differentiation with increased striation and myofibre formation. Such behavior is commonly found for confluent cells in differentiation medium. These results suggest that mechanical changes in stiffness and applied pressure might be a relevant stimulation for changes in muscle cell behavior.

Keywords: C2C12 cells, compression, force, satellite cells, skeletal muscle

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7557 Effect of Distance Education Students Motivation with the Turkish Language and Literature Course

Authors: Meva Apaydin, Fatih Apaydin

Abstract:

Role of education in the development of society is great. Teaching and training started with the beginning of the history and different methods and techniques which have been applied as the time passed and changed everything with the aim of raising the level of learning. In addition to the traditional teaching methods, technology has been used in recent years. With the beginning of the use of internet in education, some problems which could not be soluted till that time has been dealt and it is inferred that it is possible to educate the learners by using contemporary methods as well as traditional methods. As an advantage of technological developments, distance education is a system which paves the way for the students to be educated individually wherever and whenever they like without the needs of physical school environment. Distance education has become prevalent because of the physical inadequacies in education institutions, as a result; disadvantageous circumstances such as social complexities, individual differences and especially geographical distance disappear. What’s more, the high-speed of the feedbacks between teachers and learners, improvement in student motivation because there is no limitation of time, low-cost, the objective measuring and evaluation are on foreground. In spite of the fact that there is teaching beneficences in distance education, there are also limitations. Some of the most important problems are that : Some problems which are highly possible to come across may not be solved in time, lack of eye-contact between the teacher and the learner, so trust-worthy feedback cannot be got or the problems stemming from the inadequate technological background are merely some of them. Courses are conducted via distance education in many departments of the universities in our country. In recent years, giving lectures such as Turkish Language, English, and History in the first grades of the academic departments in the universities is an application which is constantly becoming prevalent. In this study, the application of Turkish Language course via distance education system by analyzing advantages and disadvantages of the distance education system which is based on internet.

Keywords: distance education, Turkish language, motivation, benefits

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7556 Nitrate Removal from Drinking Water Using Modified Natural Nanozeolite

Authors: T. Meftah, M. M. Zerafat, S. Sabbaghi

Abstract:

Nitrate compounds are considered as groundwater contaminants, the concentration of which has been growing in these resources during recent years. As a result, it seems necessary to use effective methods to remove nitrate from water and wastewater. Adsorption process is generally considered more economical in water treatment. Natural clinoptilolite zeolite is one of the best absorbents because of its high capacity and low cost.In this research, we are going to modify zeolite nanoparticles as a chemical modification. Zeolite nanoparticles have been modified with a kind of organosilane, like 3-aminopropyltriethoxysilane. The advantage of this modification method, in comparison with physical modification, is the good stability in various environmental conditions. In this research, absorbent properties have been analyzed by PSA, FTIR and CHN elemental analysis. Also, nitrate adsorption by modified nanoparticles was examined by UV-Vis spectroscopy. There would be 〖NH〗_2 groups on the zeolite surface as a result of organosilane modification. In order to adsorption of nitrate, we need to convert 〖NH〗_2 groups to〖NH〗_4^+, that it is possible in acidic condition. As a result, the best nitrate removal is possible in the lowest concentration and pH. We obtained 80.12% nitrate removal in pH=3 and 50 mg⁄l nitrate concentration and 4 g⁄l absorbent optimum concentration.

Keywords: nitrate removal, zeolite, surface modification, organosilane

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7555 Numerical Evaluation of Deep Ground Settlement Induced by Groundwater Changes During Pumping and Recovery Test in Shanghai

Authors: Shuo Wang

Abstract:

The hydrogeological parameters of the engineering site and the hydraulic connection between the aquifers can be obtained by the pumping test. Through the recovery test, the characteristics of water level recovery and the law of surface subsidence recovery can be understood. The above two tests can provide the basis for subsequent engineering design. At present, the deformation of deep soil caused by pumping tests is often neglected. However, some studies have shown that the maximum settlement subject to groundwater drawdown is not necessarily on the surface but in the deep soil. In addition, the law of settlement recovery of each soil layer subject to water level recovery is not clear. If the deformation-sensitive structure is deep in the test site, safety accidents may occur. In this study, the pumping test and recovery test of a confined aquifer in Shanghai are introduced. The law of measured groundwater changes and surface subsidence are analyzed. In addition, the fluid-solid coupling model was established by ABAQUS based on the Biot consolidation theory. The models are verified by comparing the computed and measured results. Further, the variation law of water level and the deformation law of deep soil during pumping and recovery tests under different site conditions and different times and spaces are discussed through the above model. It is found that the maximum soil settlement caused by pumping in a confined aquifer is related to the permeability of the overlying aquitard and pumping time. There is a lag between soil deformation and groundwater changes, and the recovery rate of settlement deformation of each soil layer caused by the rise of water level is different. Finally, some possible research directions are proposed to provide new ideas for academic research in this field.

Keywords: coupled hydro-mechanical analysis, deep ground settlement, numerical simulation, pumping test, recovery test

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7554 Strengthening of Reinforced Concrete Beam-Column Joint by Reversible Mixed Technologies of FRP

Authors: Nasser-Eddine Attari

Abstract:

After the earthquake many structures were classified as slightly damaged and, being uneconomic to replace them, at least in the short term, suitable means of repairs of the beam column joint area are being studied. Furthermore there exist a large number of buildings that need retrofitting of the joints before the next earthquake. The paper reports the results of the experimental programme, constituted of three beam-column reinforced concrete joints at a scale of one to three (1/3) tested under the effect of a pre-stressed axial load acting over the column. The beams were subjected at their ends to an alternate cyclic loading under displacement control to simulate a seismic action. Strain and cracking fields were monitored with the help a digital recording camera. Following the analysis of the results, a comparison can be made between the performances in terms of ductility, strength and mode of failure of the different strengthening solution considered.

Keywords: fibrereinforced polymers, joints, reinforced concrete, beam columns

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7553 Historical Geography of Lykaonia Region

Authors: Asuman Baldiran, Erdener Pehlivan

Abstract:

In this study, the root of the name Lykaonia and the geographical area defined as Lykaonia Region are mentioned. In this context, information concerning the settlements of Paleolithic Age, Neolithic Age and Chalcolithic Age are given place. Particularly the settlements belonging to Classical Age are localized and brief information about the history of these settlements is provided. In the light of this information, roads of Antique period in the region are evaluated.

Keywords: ancient cities, central anatolia, historical geography, Lykaonia region

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7552 Evaluation of Erosive Wear Resistance of Commercial Hard Coatings with Plasma Nitride and Without Plasma Nitride in Aluminium Die Casting

Authors: A. Mohammed, R. Lewis, M. Marshall

Abstract:

Commonly used coatings to protect tools in die casting were used. A heat treatment and then surface coating can have a large effect on erosion damage. Samples have been tested to evaluate their resistances to erosive wear and to assess how this compares with behaviour seen for untreated material. Five commercial (PN + TiN), (PN + TiAlCN), (TiN X 2), (TiN), and (TiAlCN) coatings have been evaluated for their wear resistance. The objective was to permit an optimized selection of coatings to be used to give good resistance to erosive wear. A test-Rig has been developed to study the erosive wear in aluminium die casting and provide an environment similar to industrial operation that is more practical than using actual machines. These surfaces were analysed using a Scanning Electron Microscope (SEM) and Optical Microscopes each with a different level of resolution. Examination of coating materials revealed an important parameter associated with the failure of the coating materials.This was adhesion of the coating material to the substrate surface. A well-adhered coating withstands wear much better compared to the poorest-adhering coating.

Keywords: solid particle erosion, PVD-coatings, steel, erosion testing

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7551 Specification Requirements for a Combined Dehumidifier/Cooling Panel: A Global Scale Analysis

Authors: Damien Gondre, Hatem Ben Maad, Abdelkrim Trabelsi, Frédéric Kuznik, Joseph Virgone

Abstract:

The use of a radiant cooling solution would enable to lower cooling needs which is of great interest when the demand is initially high (hot climate). But, radiant systems are not naturally compatibles with humid climates since a low-temperature surface leads to condensation risks as soon as the surface temperature is close to or lower than the dew point temperature. A radiant cooling system combined to a dehumidification system would enable to remove humidity for the space, thereby lowering the dew point temperature. The humidity removal needs to be especially effective near the cooled surface. This requirement could be fulfilled by a system using a single desiccant fluid for the removal of both excessive heat and moisture. This task aims at providing an estimation of the specification requirements of such system in terms of cooling power and dehumidification rate required to fulfill comfort issues and to prevent any condensation risk on the cool panel surface. The present paper develops a preliminary study on the specification requirements, performances and behavior of a combined dehumidifier/cooling ceiling panel for different operating conditions. This study has been carried using the TRNSYS software which allows nodal calculations of thermal systems. It consists of the dynamic modeling of heat and vapor balances of a 5m x 3m x 2.7m office space. In a first design estimation, this room is equipped with an ideal heating, cooling, humidification and dehumidification system so that the room temperature is always maintained in between 21C and 25C with a relative humidity in between 40% and 60%. The room is also equipped with a ventilation system that includes a heat recovery heat exchanger and another heat exchanger connected to a heat sink. Main results show that the system should be designed to meet a cooling power of 42W.m−2 and a desiccant rate of 45 gH2O.h−1. In a second time, a parametric study of comfort issues and system performances has been achieved on a more realistic system (that includes a chilled ceiling) under different operating conditions. It enables an estimation of an acceptable range of operating conditions. This preliminary study is intended to provide useful information for the system design.

Keywords: dehumidification, nodal calculation, radiant cooling panel, system sizing

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7550 Magnetite Nanoparticles Immobilized Pectinase: Preparation, Characterization and Application for the Fruit Juices Clarification

Authors: Leila Mosafa, Majid Moghadam, Mohammad Shahedi

Abstract:

In this work, pectinase was immobilized on the surface of silica-coated magnetite nanoparticles via covalent attachment. The magnetite-immobilized enzyme was characterized by Fourier transform infrared spectroscopy, X-ray powder diffraction, scanning electron microscopy and vibrating sample magnetometry techniques. Response surface methodology using Minitab Software was applied for statistical designing of operating conditions in order to immobilize pectinase on magnetic nanoparticles. The optimal conditions were obtained at 30°C and pH 5.5 with 42.97 µl pectinase for 2 h. The immobilization yield was 50.6% at optimized conditions. Compared to the free pectinase, the immobilized pectinase was found to exhibit enhanced enzyme activity, better tolerance to the variation of pH and temperature, and improved storage stability. Both free and immobilized samples reduced the viscosity of apple juice from 1.12 to 0.88 and 0.92 mm2s-1, respectively, after 30 min at their optimum temperature. Furthermore, the immobilized enzyme could be reused six consecutive cycles and the efficiency loss in viscosity reduction was found to be only 8.16%.

Keywords: magnetite nanoparticles, pectinase enzyme, immobilization, juice clarification, enzyme activity

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7549 Transversal Connection Strengthening of T Section Beam Bridge with Brace System

Authors: Chen Chen

Abstract:

T section beam bridge has been widely used in China as it is low cost and easy to erect. Some of T section beam bridges only have end diagrams and the adjacent girders are connected by wet-joint along span, which leads to the damage of transversal connection becomes a serious problem in operation and maintenance. This paper presents a brace system to strengthen the transversal connection of T section beam bridge. The strengthening effect was discussed by experiments and finite element analysis. The results show that the proposed brace system can improve load transfer between adjacent girders. Based on experiments and FEA model, displacement of T section beam with proposed brace system reduced 14.9% and 19.1% respectively. Integral rigidity increased 19.4% by static experiments. The transversal connection of T section beam bridge can be improved efficiently.

Keywords: experiment, strengthening, T section beam bridge, transversal connection

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7548 The Influence of Substrate and Temperature on the Growth of Phytophthora palmivora of Cocoa Black Pod Disease

Authors: Suhaida Salleh, Tee Yei Kheng

Abstract:

Black pod is the most commonly destructive disease of cacao (Theobroma cacao) which cause major losses to global production of cocoa beans. The genus of Phytophthora is the important pathogen of this disease worldwide. The species of P. megakarya causes black pod disease in West Africa, whereas P. capsici and P. citrophthora cause the incident in Central and South America. In Malaysia, this disease is caused by P. palmivora which infect all stages of pod development including flower cushion, cherelle, immature and mature pods. This pathogen destroys up to 10% of trees yearly through stem cankers and causes 20 to 30% pod damages through black pod rot. Since P. palmivora has a high impact on cocoa yield, it is crucial to identify some of the abiotic factors that can constrain their growth. In an effort to evaluate the effect of different substrates and temperatures to the growth of P. palmivora, a laboratory study was done under a different range of temperatures. Different substrate for the growth of P. palmivora were used which are corn meal agar (CMA) media and detached pod of cocoa. An agar plug of seven days old of P. palmivora growth was transferred on both substrates and incubated at 24, 27, 30, 33 and 36ᵒC, respectively. The diameter of lesion on pod and the cultural growth of pathogen was recorded for 7 consecutive days. The optimum incubation temperature of P. palmivora on both substrates is at 27ᵒC. However, the growth tends to be inhibited as the temperature increases. No lesion developed on pod surface incubated at 36ᵒC and only a small lesion observed at 33ᵒC. The sporulation with the formation of white mycelial growth on pod surface was only visible at optimum temperature, 27ᵒC. On CMA, the pathogen grew over the entire range of temperatures tested. The study is, therefore, concluded that P. palmivora grow the best at temperature of 27ᵒC on both substrates and their growth begin to inhibit when the temperature rises to more than 27ᵒC. The growth pattern of this pathogen is similar on both pod surface and cultural media.

Keywords: cocoa, Phytophthora palmivora, substrate, temperature

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7547 Performance Study of Scraped Surface Heat Exchanger with Helical Ribbons

Authors: S. Ali, M. Baccar

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In this work, numerical simulations were carried out using a specific CFD code in order to study the performance of an innovative Scraped Surface Heat Exchanger (SSHE) with helical ribbons for Bingham fluids (threshold fluids). The resolution of three-dimensional form of the conservation equations (continuity, momentum and energy equations) was carried out basing on the finite volume method (FVM). After studying the effect of dimensionless numbers (axial Reynolds, rotational Reynolds and Oldroyd numbers) on the hydrodynamic and thermal behaviors within SSHE, a parametric study was developed, by varying the width of the helical ribbon, the clearance between the stator wall and the tip of the ribbon and the number of turns of the helical ribbon, in order to improve the heat transfer inside the exchanger. The effect of these geometrical numbers on the hydrodynamic and thermal behaviors was discussed.

Keywords: heat transfer, helical ribbons, hydrodynamic behavior, parametric study, SSHE, thermal behavior

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7546 Investigation on Flexural Behavior of Non-Crimp 3D Orthogonal Weave Carbon Composite Reinforcement

Authors: Sh. Minapoor, S. Ajeli

Abstract:

Non-crimp three-dimensional (3D) orthogonal carbon fabrics are one of the useful textiles reinforcements in composites. In this paper, flexural and bending properties of a carbon non-crimp 3D orthogonal woven reinforcement are experimentally investigated. The present study is focused on the understanding and measurement of the main bending parameters including flexural stress, strain, and modulus. For this purpose, the three-point bending test method is used and the load-displacement curves are analyzed. The influence of some weave's parameters such as yarn type, geometry of structure, and fiber volume fraction on bending behavior of non-crimp 3D orthogonal carbon fabric is investigated. The obtained results also represent a dataset for the simulation of flexural behavior of non-crimp 3D orthogonal weave carbon composite reinforcement.

Keywords: non-crimp 3D orthogonal weave, carbon composite reinforcement, flexural behavior, three-point bending

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7545 An Optimized Method for Calculating the Linear and Nonlinear Response of SDOF System Subjected to an Arbitrary Base Excitation

Authors: Hossein Kabir, Mojtaba Sadeghi

Abstract:

Finding the linear and nonlinear responses of a typical single-degree-of-freedom system (SDOF) is always being regarded as a time-consuming process. This study attempts to provide modifications in the renowned Newmark method in order to make it more time efficient than it used to be and make it more accurate by modifying the system in its own non-linear state. The efficacy of the presented method is demonstrated by assigning three base excitations such as Tabas 1978, El Centro 1940, and MEXICO CITY/SCT 1985 earthquakes to a SDOF system, that is, SDOF, to compute the strength reduction factor, yield pseudo acceleration, and ductility factor.

Keywords: single-degree-of-freedom system (SDOF), linear acceleration method, nonlinear excited system, equivalent displacement method, equivalent energy method

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7544 Rolling Contact Fatigue Failure Analysis of Ball Bearing in Gear Box

Authors: Piyas Palit, Urbi Pal, Jitendra Mathur, Santanu Das

Abstract:

Bearing is an important machinery part in the industry. When bearings fail to meet their expected life the consequences are increased downtime, loss of revenue and missed the delivery. This article describes the failure of a gearbox bearing in rolling contact fatigue. The investigation consists of visual observation, chemical analysis, characterization of microstructures using optical microscopes and hardness test. The present study also considers bearing life as well as the operational condition of bearings. Surface-initiated rolling contact fatigue, leading to a surface failure known as pitting, is a life-limiting failure mode in many modern machine elements, particularly rolling element bearings. Metallography analysis of crack propagation, crack morphology was also described. Indication of fatigue spalling in the ferrography test was also discussed. The analysis suggested the probable reasons for such kind of failure in operation. This type of spalling occurred due to (1) heavier external loading condition or (2) exceeds its service life.

Keywords: bearing, rolling contact fatigue, bearing life

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7543 Electronic Payment Recording with Payment History Retrieval Module: A System Software

Authors: Adrian Forca, Simeon Cainday III

Abstract:

The Electronic Payment Recording with Payment History Retrieval Module is developed intendedly for the College of Science and Technology. This system software innovates the manual process of recording the payments done in the department through the development of electronic payment recording system software shifting from the slow and time-consuming procedure to quick yet reliable and accurate way of recording payments because it immediately generates receipts for every transaction. As an added feature to its software process, generation of recorded payment report is integrated eliminating the manual reporting to a more easy and consolidated report. As an added feature to the system, all recorded payments of the students can be retrieved immediately making the system transparent and reliable payment recording software. Viewing the whole process, the system software will shift from the manual process to an organized software technology because the information will be stored in a logically correct and normalized database. Further, the software will be developed using the modern programming language and implement strict programming methods to validate all users accessing the system, evaluate all data passed into the system and information retrieved to ensure data accuracy and reliability. In addition, the system will identify the user and limit its access privilege to establish boundaries of the specific access to information allowed for the store, modify, and update making the information secure against unauthorized data manipulation. As a result, the System software will eliminate the manual procedure and replace with an innovative modern information technology resulting to the improvement of the whole process of payment recording fast, secure, accurate and reliable software innovations.

Keywords: collection, information system, manual procedure, payment

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7542 Parametric Study of 3D Micro-Fin Tubes on Heat Transfer and Friction Factor

Authors: Shima Soleimani, Steven Eckels

Abstract:

One area of special importance for the surface-level study of heat exchangers is tubes with internal micro-fins (< 0.5 mm tall). Micro-finned surfaces are a kind of extended solid surface in which energy is exchanged with water that acts as the source or sink of energy. Significant performance gains are possible for either shell, tube, or double pipe heat exchangers if the best surfaces are identified. The parametric studies of micro-finned tubes that have appeared in the literature left some key parameters unexplored. Specifically, they ignored three-dimensional (3D) micro-fin configurations, conduction heat transfer in the fins, and conduction in the solid surface below the micro-fins. Thus, this study aimed at implementing a parametric study of 3D micro-finned tubes that considered micro-fine height and discontinuity features. A 3D conductive and convective heat-transfer simulation through coupled solid and periodic fluid domains is applied in a commercial package, ANSYS Fluent 19.1. The simulation is steady-state with turbulent water flow cooling the inner wall of a tube with micro-fins. The simulation utilizes a constant and uniform temperature on the tube outer wall. Performance is mapped for 18 different simulation cases, including a smooth tube using a realizable k-ε turbulence model at a Reynolds number of 48,928. Results compared the performance of 3D tubes with results for the similar two-dimensional (2D) one. Results showed that the micro-fine height has a greater impact on performance factors than discontinuity features in 3D micro-fin tubes. A transformed 3D micro-fin tube can enhance heat transfer, and pressure drops up to 21% and 56% compared to a 2D one, respectfully.

Keywords: three-dimensional micro-fin tube, heat transfer, friction factor, heat exchanger

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7541 Characterization of Surface Suction Grippers for Continuous-Discontinuous Fiber Reinforced Semi-Finished Parts of an Automated Handling and Preforming Operation

Authors: Jürgen Fleischer, Woramon Pangboonyanon, Dominic Lesage

Abstract:

Non-metallic lightweight materials such as fiber reinforced plastics (FRP) become very significant at present. Prepregs e.g. SMC and unidirectional tape (UD-tape) are one of raw materials used to produce FRP. This study concerns with the manufacturing steps of handling and preforming of this UD-SMC and focuses on the investigation of gripper characteristics regarding gripping forces in normal and lateral direction, in order to identify suitable operating pressures for a secure gripping operation. A reliable handling and preforming operation results in a higher adding value of the overall process chain. As a result, the suitable operating pressures depending on travelling direction for each material type could be shown. Moreover, system boundary conditions regarding allowable pulling force in normal and lateral directions during preforming could be measured.

Keywords: continuous-discontinuous fiber reinforced plastics, UD-SMC-prepreg, handling, preforming, prepregs, sheet moulding compounds, surface suction gripper

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7540 The Shadowy History of Berlin Underground: 1939-45/Der Schattenmann: Tagebuchaufzeichnungen 1938-1945

Authors: Christine Wiesenthal

Abstract:

This paper asks how to read a particularly vexed and complicated life writing text. For over half a century, the wartime journals of Ruth Andreas Friedrich (1901-1977) circulated as among a handful of more or less authoritative and “authentic” first-hand accounts of German resistance under Hitler. A professional journalist, Andreas Friedrich is remembered today largely through her publications at the war’s end, which appeared in English as Berlin Underground (published by Henry Holt in 1947), just before their publication in Germany as Der Schattenmann “The Shadow Man” (also in 1947). A British edition by the now obscure Latimer House Limited (London) followed in 1948; it is based closely on but is not identical to, the Henry Holt American edition, which in turn differs significantly from its German counterpart. Both Berlin Underground and Der Schattenmann figure Andreas-Friedrich as a key figure in an anti-fascist cell that operated in Berlin under the code name “Uncle Emil,” and provide a riveting account of political terror, opportunism, and dissent under the Nazi regime. Recent scholars have, however, begun to raise fascinating and controversial questions about Andreas-Friedrich’s own writing/reconstruction process in compiling the journals and about her highly selective curatorial role and claims. The apparent absence of any surviving original manuscript for Andreas-Friedrich’s journals amplifies the questions around them. Crucially, so too does the role of the translator of the English editions of Berlin Underground, the enigmatic June Barrows Mussey, a subject that has thus far gone virtually unnoticed and which this paper will focus on. Mussey, a prolific American translator, simultaneously cultivated a career as a professional magician, publishing a number of books on that subject under the alias Henry Hay. While the record indicates that Mussey attempted to compartmentalize his professional life, research into the publishing and translation history of Berlin Underground suggests that the two roles converge in the fact of the translator’s invisibility, by effacing the traces of his own hand and leaving unmarked his own significant textual interventions, Mussey, in effect, edited, abridged, and altered Andreas Friedrich’s journals for the second time. In fact, it could be said that while the fictitious “Uncle Emil” is positioned as “the shadow man” of the German edition, Mussey himself also emerges as precisely that in the English rendering of the journals. The implications of Mussey’s translation of Andreas Friedrich’s journals are one of the most important un-examined gaps in the shadowy publishing history of Berlin Underground, a history full of “tricks” (Mussey’s words) and illusions of transparency. Based largely on archival research of unpublished materials and methods of close reading and comparative analysis, this study will seek to convey some preliminary insights and exploratory work and frame questions toward what is ultimately envisioned as an experimental project in poetic historiography. As this work is still in the early stages, it would be especially welcome to have the opportunity provided by this conference to connect with a community of life writing colleagues who might help think through some of the challenges and possibilities that lie ahead.

Keywords: women’s wartime diaries, translation studies, auto/biographical theory, politics of life writing

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7539 CAGE Questionnaire as a Screening Tool for Hazardous Drinking in an Acute Admissions Ward: Frequency of Application and Comparison with AUDIT-C Questionnaire

Authors: Ammar Ayad Issa Al-Rifaie, Zuhreya Muazu, Maysam Ali Abdulwahid, Dermot Gleeson

Abstract:

The aim of this audit was to examine the efficiency of alcohol history documentation and screening for hazardous drinkers at the Medical Admission Unit (MAU) of Northern General Hospital (NGH), Sheffield, to identify any potential for enhancing clinical practice. Data were collected from medical clerking sheets, ICE system and directly from 82 patients by three junior medical doctors using both CAGE questionnaire and AUDIT-C tool for newly admitted patients to MAU in NGH, in the period between January and March 2015. Alcohol consumption was documented in around two-third of the patient sample and this was documented fairly accurately by health care professionals. Some used subjective words such as 'social drinking' in the alcohol units’ section of the history. CAGE questionnaire was applied to only four patients and none of the patients had documented advice, education or referral to an alcohol liaison team. AUDIT-C tool had identified 30.4%, while CAGE 10.9%, of patients admitted to the NGH MAU as hazardous drinkers. The amount of alcohol the patient consumes positively correlated with the score of AUDIT-C (Pearson correlation 0.83). Re-audit is planned to be carried out after integrating AUDIT-C tool as labels in the notes and presenting a brief teaching session to junior doctors. Alcohol misuse screening is not adequately undertaken and no appropriate action is being offered to hazardous drinkers. CAGE questionnaire is poorly applied to patients and when satisfactory and adequately used has low sensitivity to detect hazardous drinkers in comparison with AUDIT-C tool. Re-audit of alcohol screening practice after introducing AUDIT-C tool in clerking sheets (as labels) is required to compare the findings and conclude the audit cycle.

Keywords: alcohol screening, AUDIT-C, CAGE, hazardous drinking

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7538 A Cultural Materialistic Approach to Toni Morrison’s Beloved and the Bluest Eye

Authors: Irfan Mehmood

Abstract:

The goal of this paper is to examine Toni Morrison's novels Beloved and The Bluest Eye from a cultural materialistic perspective. The history and society of African Americans provide the inspiration for the stories of Beloved and The Bluest Eye. The cultural materialist elements and characteristics of Morrison's literary text will be highlighted in this study. The topic covered in this paper will include racism, gender discrimination, social class differences, and slavery in the text. In other words, the study will focus on the underrepresented groups in society, including women, slaves, and Afro-Americans. In this aspect, Toni Morrison is a fantastic writer whose works are full of diverse races. Morrison uses her incredibly well-informed language and well-produced stories to attempt to illuminate many facets of American life. She establishes a distinctive style of writing that sharply contrasts the suffering and enslavement of Afro-Americans with the traditional writings of Euro-American authors. Morrison shows a profound understanding of the exploitation of Afro-Americans in terms of race, gender, and class conflict in Beloved and The Bluest Eye. A unique culture and the history of a typically ignored set of people whose minds and societies have been permanently changed by class, racial, and gender discrimination were introduced through the study of Morrison's chosen novels. Toni Morrison places a lot of emphasis on the marginalized members of society, particularly in terms of class, ethnicity, and gender, because the majority of the key characters in her book are black. Therefore, the purpose of this essay is to concentrate on the culturally materialistic elements of Morrison's Beloved and The Bluest Eye and to ascertain the author's position on these minorities.

Keywords: race, slavery, social class, Toni Morrison, African American culture

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7537 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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7536 Assessment of Chemical and Physical Properties of Surface Water Resources in Flood Affected Area

Authors: Siti Hajar Ya’acob, Nor Sayzwani Sukri, Farah Khaliz Kedri, Rozidaini Mohd Ghazi, Nik Raihan Nik Yusoff, Aweng A/L Eh Rak

Abstract:

Flood event that occurred in mid-December 2014 in East Coast of Peninsular Malaysia has driven attention from the public nationwide. Apart from loss and damage of properties and belongings, the massive flood event has introduced environmental disturbances on surface water resources in such flood affected area. A study has been conducted to measure the physical and chemical composition of Galas River and Pergau River prior to identification the flood impact towards environmental deterioration in surrounding area. Samples that have been collected were analyzed in-situ using YSI portable instrument and also in the laboratory for acid digestion and heavy metals analysis using Atomic Absorption Spectroscopy (AAS). Results showed that range of temperature (0C), DO (mg/L), Ec (µs/cm), TDS (mg/L), turbidity (NTU), pH, and salinity were 25.05-26.65, 1.51-5.85, 0.032-0.054, 0.022-0.035, 23.2-76.4, 3.46-7.31, and 0.01-0.02 respectively. The results from this study could be used as a primary database to evaluate the status of water quality of the respective river after the massive flood.

Keywords: flood, river, heavy metals, AAS

Procedia PDF Downloads 375