bluuebunny/crossref_metadata_2025 huggingface dataset:
Study about Stress-Strain Properties with Mini Specimen and Microstructure of Nuclear Fuel Element Cladding of Al-Alloy (98% Al + 1% Fe + 1% Ni) after Being Tempered at Temperatures between (100 – 650) °C
Authors: Sudjadi Usman , Hasa M. Husna Al
Published: April 2015

Stress-strain properties with mini specimen and micro structure of nuclear fuel elements cladding of Al-alloy (98% Al + 1% Fe + 1% Ni) after tempered at temperatures (100-650) °C, for 1 hour have been studied. Al-alloy (98% Al + 1% Fe + 1% Ni) was made for cladding nuclear fuel elements of research reactor. Al-alloy (98% Al + 1% Fe + 1% Ni) as cladding material has been on the rollers and then made a mini specimen tensile test samples. The mini specimen tensile test samples were tempered at temperatures of (100-650) °C, respectively 1 hour. Samples were tested to determine properties of tensile stress-strain with a mini-tensile test specimen. The tensile test equipment can attract maximum sample 5 kN, Shimadzu Autograph AGS-brand artificial 5kN, made in Japan. Then the samples were broken section micro structure observed by SEM (Scanning Electron Microscope). Quantitative results showed that the higher the tempering temperature, the maximum stress is decreased. The higher the tempering temperature cleavage fracture increasingly overlaps (small). This is due to the self-diffusion of Al atoms in the material when the sample tempered at (100-650) °C, for 1 hour. Observation of the microstructure by SEM (Scanning Electron Microscope) was visible presence of porosity in the sample.
The Experimental Research on Horizontal Underground Tank Magnetic Flux Leakage Testing
Authors: Zheng Mu Lin , Ling Zhang Wei , Wang Min , Kong Shuai , Guo Wei Can
Published: April 2015

Magnetic flux leakage (MFL) testing is widely used to inspect and characterize defects in storage tank floors, pipelines and other structures. In this paper, magnetic flux leakage testing technology is applied to the horizontal product oil underground tank wall inspection. The artificial defects were prefabricated on the tank wall such as corrosion pits, grooving and other artificial defects to simulate the corrosion, cracks and other actual defects in actual working conditions. The experimental research of the mutual influence between magnetic flux leakage and defects’ parameters were carried out, such as the depth and width of cracks, and depth and diameter of corrosion pits. Then the relationship between the defect’s parameter and magnetic field amplitude was obtained. The experimental results showed that, whether corrosion or crack, the depth is a very important factor affecting the leakage magnetic field amplitude. Especially for crack, width, length and the inclination angle between crack and magnetic field had great influence on the detection of the cracks, and too small angle to lead to misjudgment and undetected of crack. Therefore, single direction inspection may lead to undetected in engineering practice.
Modeling Design and Rapid Prototyping Manufacture of Cream Bottle Based on Handheld Laser Scanning
Authors: Wang Xing Xing , Wei Jin Dong , Pei Yi , Zhu Yu , Ni Hong Jun
Published: April 2015

Reverse Engineering (RE) and Rapid Prototyping (RP) were used for manufacturing cream bottle. Points cloud data of cream bottle was accessed by handheld laser scanner firstly. Then, points cloud data was handed by Imageware software and the three-dimensional model was formed by Solidworks software. Finally, the entity model was manufacturing by RP machine. In the research, rapid prototyping was combined with reverse engineering technology, manufacturing cycle was shorten, production requirements, improve efficiency and other advantages were met.
Development of a Knowledge Management System for the Basic Hand Tools and Machinery Using Ontology Technology
Authors: Sriprasert U Tit , Sriprasert A Tikit , Kalnaowakun Phuri , Yingsamcharoen Trinet
Published: April 2015

The purpose of this study was to develop a knowledge management system for basic hand tools and machinery using ontology technique for increasing information search efficiency and for practical use. Ontology technique was applied to help presenting the system in the form of semantic web using OWL and RAP languages that supported analyses in knowledge management process. The system was designed to meet users’ need. It was tested and evaluated by experts and users.The study showed that the system could help the users to efficiently use the right tools for the right jobs. According to the satisfaction evaluation, the experts and the users were very satisfied with the developed system. The satisfaction mean was 4.34 and the standard deviation was 0.54. This proved that the set hypothesis was true.
Morphology-Controlled CaCO3 Nanostructures by Modified Co-Precipitation in Pulsed Mode
Authors: Nassar M.M. , Farrag Taha Ebrahiem , Mahmoud M.S. , Abdelmonem Sayed
Published: April 2015

Calcium carbonate nanoparticles and nanorods were synthesized by precipitation from saturated sodium carbonate and calcium nitrate aqueous solutions through co precipitation method. A new rout of synthesis was done by both using pulsed mixing method and controlling the addition of calcium nitrate. The effect of the agitation speed, and the temperature on particle size and morphology were investigated. Particles were characterized using X-ray Microanalysis, X-ray analysis (XRD) and scanning electron microscopy (SEM). The results indicated that increasing the mixer rotation speed from 3425 to 15900 (rpm) decreases the average particle size to 64±7 nm. A rapid nucleation then aggregation induced by excessive shear force phenomena could explain this observation. Moreover, by increasing the reaction temperature, the products were converted from nanoparticle to nanorods. The maximum attainable aspect ratio was 6.23 at temperature of 75°C and rotation speed of 3425. Generally, temperature raise promoted a significant homoepitaxial growth in one direction toward the formation of calcite nanorods. Overall, this study can open new avenues to control the morphology of the calcium carbonate nanostructures.
Improvement of Surface Properties of Micro-Mold via SAM Coating for Fabrication of Microfluidic Device
Authors: Saha Biswajit , Lee Jung Hoon
Published: April 2015

N-octadecyltrichlorosilane [OTS, CH3(CH2)17SiCl3] self-assembled monolayer (SAM) coatings were deposited on Si micromolds by dip-coating. Chemical composition, surface roughness, friction coefficient, thermal stability and surface energy of coatings were investigated. OTS coated silicon (Si) micromolds were used to fabricate PMMA microfluidic devices by hot-embossed process. All OTS coatings were thermally stable up to 180 °C, which is higher than hot-embossing temperature of PMMA. OTS coated micromolds had low friction coefficient, adhesion and superior molding efficiency, which improved lifetime of a uncoated Si micromold from 3 to 27 times.
Properties and Peculiarities of WCCoCr Coatings Formed by Multi-Chamber Detonation Sprayer
Authors: Tyurin Yu.N. , Kovaleva M.G. , Vasilik N.J. , Kolisnichenko O.V. , Prozorova M.S. , Arseenko M.Yu. , Sirota V.V. , Pavlenko I.A.
Published: April 2015

Multi-chamber detonation sprayer (MCDS) was applied for deposition of WC-Co-Cr powder coatings on corrosion-resistant steel. Powder AMPERIT®554.074 WC-Co-Cr was used to deposit of a coatings. The coatings microstructures and phase compositions were characterized using SEM, OM and XRD techniques. Measurement of the microhardness of samples was done with a micro-hardness tester DM – 8B using a Vickers’s indenter with load on of 0.3 N. It was established that MCDS has provided the conditions for formation of a dense layer with porosity of less than 1.5 % and microhardness 750±50 HV0.3.
Strength Development of Fine Grained Mortar Containing Fly Ash and Rice Husk Ash
Authors: Jamellodin Zalipah , Hamidah Mohd Saman , Adnan Suraya Hani , Mohammad Noor Shuhada , Wan Yusof Wan Yuslinda
Published: April 2015

Fine grained mortar (FGM) offers a new innovative technology binder system. The innovative technique is achieved by using a small maximum grain size of 600μm for the mortars. Most of the previous studies have focused on the FA to be replaced in the FGM. There is still lacking of research of using other pozzolanas in making FGM. This paper presents a study of the strength of FGM with partially replacement of ordinary Portland cement (OPC) with fine fly ash (FA) and ground rice husk ash (RHA). Flexural and compressive strength of FGM were tested. The results show that the use of FA and RHA produces FGM with improved strength with the replacement up to 20% than that of the control FGM. The use of FA and RHA is very effective in enhancing strength at the later age of FGM.
Rutting Performance of Hot Mix Asphalt Mixture Using Nanopolyacrylate Polymer Modifier
Authors: Shaffie E. , Ahmad J. , Kamarun D.
Published: April 2015

Rutting is a common pavement failure in road pavement. Rutting occurs mainly due to several factors including increasing of vehicles numbers, environmental conditions and also due to construction and design errors. As a consequence the service life of asphalt pavement is affected and will be decreased. Various researches reported that using different types of polymers in bitumen modification could be a solution to delay deterioration of asphalt pavement. The main purpose of the study was to investigate the effect of the NPA polymer modifier on the rutting behaviour of the asphalt mixtures through Superpave designed mixtures. . Two different types of dense graded Superpave HMA mix were developed consists of Control mix and nanopolyacrylate (NPA) mix. Results showed that all the mixes passed the Superpave volumetric properties criteria which indicate that these mixtures were good with respect to durability and flexibility. Furthermore there is a significant difference between Control mix and NPA mix in terms of rutting in which rut depth after 8000 passes for Control mix was 5.94 mm while for NPA mix was 2.98 mm. The results of this investigation indicated that the Rutting test result of NPA demonstrates 3% better resistance to rutting than those prepared using Control mix. This is due to the addition of NPA to the bitumen has certainly improved the bitumen properties significantly and hence increase the resistant to rutting of the asphalt mixture. Therefore, it can be concluded that NPA polymer is feasible to be used as asphalt modifier and has potential for improvement in the field of pavement material and construction in future.
Effect of Si on the Thermal Stability of Ferritic Heat-Resistant Ductile Iron
Authors: Choe Kyeong Hwan , Lee Kyong Whoan , Kim Myung Ho
Published: April 2015

The effect of silicon (Si) on the stability of heat-resistant ductile iron having ferrite matrix in high temperature was investigated by dilatometric test. Microstructure of heat-resistant ferritic ductile iron consists of ferrite, eutectic carbide at eutectic cell boundaries, precipitated carbide in grain and graphite. Pearlite was found around eutectic carbide in some specimens, however, all pearlite was decomposed by the annealing treatment. As Si content was increased, the number and size of carbide decreased and full ferrite matrix were obtained. The starting temperature of ferrite-austenite transformation and the coefficient of thermal expansion increased with the increase of Si content. The growth of Si 6.0wt% specimen during held at 1,000 oC is lower than other specimens, and it is considered that in the case of Si 6.0wt% specimen, the carbon movement is restrained due to the low solubility of carbon in matrix. In the case of annealed specimens, the contraction during ferrite-austenite transformation was not found when heating. This is because the re-distribution of the graphite was happened through the movement of carbon during annealing treatment.
Polymer-Based Fluidic Devices Integrated with Perforated Conical Nanopores in Freestanding Polymer Membranes
Authors: Choi Jun Seo , Park Sung Gook
Published: April 2015

Although nanoimprint lithography (NIL) can successfully fabricate structures down to 10 nm [1], it is difficult to produce perforated pores with diameters less than 100 nm in freestanding polymer membranes. Since it requires molding using a stamp with extremely high aspect ratio to achieve high mechanical stability for the membrane fully released from a substrate. We utilized silicon microneedle structures as an imprinting mold that overcomes these issues. Also, pressed self-perfection (PSP) process was employed after nanoimprinting to further reduce the pore size. Additionally, the membranes were integrated with microfluidic devices to measure current-voltage curves in order to determine pore size indirectly.
Formation of Tobermorite at Different Materials Composition of Aerated Concrete
Authors: Venhodová Ester , Janovský Radek , Drochytka Rostislav
Published: April 2015

For the production of quality autoclaved aerated concrete product is necessary to know the chemical composition of raw materials and with regard to that optimize the recipe. This paper deals with the verification of the influence raw materials mixture ́s chemical composition, the reactivity of the silica source and the molar ratio C/S on the shape and amount of tobermorite crystals in autoclaved aerated concrete.
The Effect of Alkali Silica Gel Formation from Alkali Silica Reaction in Mesoscopic Scale
Authors: Tabet M. , Guettala Abdelhamid
Published: April 2015

In this article we treat a pathological problem for a better understanding of the phenomena of ASR; the modeling of ASR has been represented in a relative element of volume (REV) in mesoscopic scale. The method used to estimate the formation of ASG is the kinematic estimation of the ASR where it generates in the end an expansion, thus modeling leads to a better range of understanding of the rheological behavior of a concrete with ASR.The numerical model adopted to validate the effect of the expansion of alkali silica gel in terms of strain/stress is a phenomenological one, where it gives sustainable results with the rheological models.
Use of Theory of Hypothesis at Evaluation of Creep Curves
Authors: Reznicek Martin , Pata Vladimír , Manas David , Stanek Michal , Skrobak Adam , Ovsik Martin , Malochova Martina
Published: April 2015

This article focuses on the evaluation of tests with a small repeatability which are characterized by their financial or time demands. The beginning of the article assess the current state of the problem and different approaches to it, focusing on the evaluation of creep tests characterized especially by their very typical little repeatability. Then the article describes the method for testing the creep properties of the irradiated material at raised temperatures. Next, the results are graphically confronted with the subjective evaluation of the observer and using the Mann-Whitney test. This test is used to determine whether the measured data comes from the same basic set or originate with the chosen confidence level. The results show the significance of the use of this test which is calculated with a certain probability.
Ionizing Radiation Effect of PBT Measured by Nano-Indentation Test
Authors: Ovsik Martin , Manas David , Manas Miroslav , Stanek Michal , Skrobak Adam , Kratky Petr
Published: April 2015

The paper presents an experimental study of the effect of beta radiation on nanomechanical properties of surface layer of PBT. Irradiation of polymers initiates cross-linking process in the structure especially in nanolayers. Applied radiation doses (66, 132 and 198 kGy) caused different nanomechanical changes which have a significant effect on the final properties of the tested PBT. Beta irradiation of the examined thermoplastic caused the growth of values of material parameters as nanoindentation hardness, nanoindentation modulus or deformation work. The improvement of nanomechanical properties was measured by the nanoindentation test.
Influence of Content of Crosslinking Agent on the Micromechanical Properties of Glass-Filled Polyamide 6
Authors: Manas David , Ovsik Martin , Manas Miroslav , Stanek Michal , Spanhelova Marcela , Bednarik Martin , Senkerik Vojtech
Published: April 2015

The process of radiation crosslinking helps to improve some mechanical properties of polymer materials. Some types of polymers do not cross-link during radiation crosslinking but degrade. In order to create 3D net in the polymer structure it is necessary to add a crosslinking agent. The specimens were prepared by injection technology with the TAIC crosslinking agent at 0, 1, 2 and 3 %. The changes of micromechanical properties of the surface layer were measured by instrumented microhardness test. It was found that micromechanical properties of the surface layer of the tested polyamide changed.
Effects of Magnesium Content on Ballistic Performance of Al-8Zn-SiC Composite after Heat Treatment Process
Authors: Sofyan Bondan Tiara , Aksari Lita , Septiani Ardita , Rahmalina Dwi
Published: April 2015

SiC – reinforced aluminium composite - has been developed to improve the ballistic performance and mobility of the armour material. Critical to obtaining ballistic resistance is that the materials must be sufficiently hard and strong, especially at the surface where a projectile will first make impact. To achieve this resistance, aluminium alloys can be strengthened by adding Zn and Mg, and reinforced with silicon carbide. This research studied the ballistic properties of aluminium composites with varied Mg. The matrix used in this study was an Al-8Zn alloy with 3-5 wt. % Mg. Silicon carbide particulate of 15 % volume fraction was used as strengthening material, which was added to the liquid matrix by stirring at 5000 rpm. The liquid composite was then squeeze cast at a pressure of 72 MPa. Then the composites were heat-treated and coated to improve the ballistic performance. Ballistic testing was performed in accordance with ASTM F1233 by using 7.62 calibre projectiles. Microstructural observation was conducted in samples, performed with optical microscope. The results showed that the as-cast hardness of the composite increased with addition of Mg content of 3, 4 and 5 wt. %. The peak hardness after ageing at 200 °C also increased with Mg addition. However, the composites were not able to withstand the 7.62 mm calibre projectile.
Experimental Analysis on Heat Transfer Enhancement of Double Pipe Heat Exchanger Using Alumina/Water Nanofluid and Baffled Twisted Tape Inserts
Authors: Sreekumar P.C. , Krishnamoorthy K. , Ratheesh R.
Published: April 2015

Heat transfer augmentation techniques ultimately results in the reduction of thermal resistance in a conventional heat exchanger by generating higher convective heat transfer coefficient. Present study with the use of Alumina (Al2O3)/water nanofluid and baffled twisted tape inserts in double pipe heat exchanger as compound augmentation technique. Experiments were conducted to evaluate the heat transfer coefficient and friction factor for the flow through the inner tube of heat exchanger in turbulent flow range (8000<Re<60000). The effect of rectangular, circular, triangular baffled twisted tape having twist ratio (y/w) 4.2 and twisted tapes without baffles of twist ratio (y/w) 4.2 and 5.2 were studied. Experiments were conducted for both water and 0.1% volume concentration Alumina/water nanofluid. It is found that the enhancement of heat transfer coefficient by using rectangular baffled twisted tape and nanofluid is about 20%. Performance evaluation criteria were found for water and nanofluid and it was observed that rectangular baffled twisted tape performs better than other twisted tapes.
Finite Element Analysis of Residual Stress Level Prediction for TIG Welding Process
Authors: Baisukhan Adirek , Nakkiew Wasawat
Published: April 2015

Tungsten Inert Gas (TIG) welding process requires high heat input during the process, when the material is cooled down non-uniform distribution of thermal strain causes residual stress which can weaken the material and fatigue life of the material. The residual stress can be measured from method such as x-ray diffraction (XRD), using strain gage of drilled hole and so on. A numerical method of constructing a finite element analysis (FEA) model can be used for predicting the residual stress level of the welding process. This paper uses the TIG welding condition for stainless steel grade 304 that the material provided the highest level of tensile strength, obtained from previous study, as a condition for the FEA model. The residual stress results from the FEA predictive model and the results from XRD were compared. In the FEA model, the workpiece, heat affected zone (HAZ), and filler metal assumed to be the same. The results showed consistent residual profile between the model and the actual measurement from XRD, but there was some discrepancy of the magnitude of residual stress which can due to the type of filler material that was used.
Finite Element Modelling of Innovative Precast Cold-Formed Steel Ferrocement as Composite Beam
Authors: Saggaff Anis , Alhajri Talal , Ismail M. , Alenezi Khaled , Ragae Mohamad
Published: April 2015

This paper describes Finite Element Modeling (FEM) of a composite beam comprised of cold formed steel section and concrete slab designed as ferrocement. Software (ANSYS, version 11) was adopted to carry out the modeling of the proposed composite beam. Experimental tests were also been carried out for three simple supported composite beams. The proposed innovative precast composite beam specimens of cold-formed steel lipped channel sections (CFS) connected with ferrocement slab were tested till failure, under two point loads positioned atquarter length of the span from support. The results showed that close agreement was observed between the FEM and experimental results for ultimate loads and load-deflection responses.
Development of High-Volume High Temperature Fly Ash Concrete (HVFAC)
Authors: Hela Rudolf , Bodnárová Lenka
Published: April 2015

To ensure sustainable concrete building industry it is necessary to decrease consumption of natural resources for manufacture of concrete and reduce content of CO2 produced during production of cement. This approach has not only ecological impact on future activities but it can also considerably reduce cost of concrete. In the Czech Republic, about 6.5 million tons of high quality fly ash is produced during classic high temperature combustion of anthracite or brown coal for production of electric energy. Fly ash produced in such way has high content of SiO2 and low content of CaO, and it is ranked among co-called siliceous fly ash, which has outstanding pozzolanic properties. This paper describes experience from experimental development of High Volume Fly Ash Concrete (HVFAC), where over 50% of fly ash is used as substitution of Portland cement for binder. High proportion of replaced Portland cement were tested in this research; impacts on strength of concrete at the age of 7 – 180 days, consistency of concrete and other related properties were observed.
Ultrasonic Inspection of Thin Duplex Steel Weld Joints by TOFD
Authors: Hodúlová Erika , Kovaříková Ingrid , Šimeková Beáta , Ulrich Koloman
Published: April 2015

The use of non-destructive inspection techniques in conventional stainless steels is well established. However the non-destructive inspection of duplex and superduplex steels is a big challenge as those steels, being composed of ferrite and austenite, have some particularities. When using ultrasound, for instance, its waves propagate well in ferrite, but suffer strong attenuation, scattering and refraction in austenite. An extended research is proposed on the inspection of duplex steels, especially in welded joints, which presents the worst problems in those steels (incorrect ferrite/austenite balance and precipitation of deleterious phases). The aim of this work was to use the TOFD ultrasonic inspection method for the thin duplex steel weld joint inspection.
The Method of Separation of Variables in the Problem of Theory of Elasticity for Radially Inhomogeneous Cylinder
Authors: Andreev Vladimir I.
Published: April 2015

The article deals with the numerical-analytical method of solving problems in the theory of elasticity of inhomogeneous bodies in terms of displacements for a circular cylinder. We consider two-and three-dimensional problems. After separation of variables, the problem is reduced to the numerical solution of the system of differential equations of the first order.
Numerical-Analytical Solution of Two-Dimensional Problem for Elastic Radially Inhomogeneous Thick-Walled Cylinder
Authors: Andreev Vladimir I.
Published: April 2015

In the [1,2] was considered method of separating of variables in three-dimensional problem for radially inhomogeneous cylinder. This problem solves in terms of displacements and reduced to infinite system of ordinary differential equations. The paper deals with the partially case – two-dimensional axisymmetric problem of the calculation of thick-walled cylindrical shell loaded by non-uniform load on the outer surface.
Calculation and Reliability Assessment of Timber Structure Bolt Connection Subjected to Double Unequal Shears
Authors: Musílek Josef , Kubečka Karel
Published: April 2015

The paper shows the calculation and reliability assessment of bolted connections subjected to unequal double shear with thin plates as outer members and inner timber member. The concrete example is calculated and explained.
Performance Enhancement of the Existing Bridges due to Overweight Vehicles with Multi-Axle Loading
Authors: Suparp Suniti , Joyklad Panuwat
Published: April 2015

This article presented the analytical results focused on the responses of existing bridges in Thailand subjected to overweight vehicles. The bridges, span lengths ranging from 5 to 20 meters, were loaded by the overweight vehicles with multi-axle loading having gross weight of 400 tons. The rating factors of bridges were also performed. The bridge strengthening methods using carbon fiber reinforcement polymers and intended settlement technique were also presented.The results indicated that the load rating factors were increased and conformed to the load rating standards. The results of this study would be a reference data to establish an alternative plan of bridge strengthening to improve the safety of the bridges under a moving of overweight vehicles.
Load-Carrying Capacity of Timber Structure Bolt Connection Subjected to Double Unequal Shears
Authors: Musílek Josef , Kubečka Karel
Published: April 2015

The paper deals with load-carrying capacity of bolted connections subjected to unequal double shears with thin plates as outer members and inner timber member. There are derived equations which describe the load-carrying capacity of this connection type in the ultimate limit state.
Selection of Insulation Materials and Insulation Performance with Consideration of Building Energy when Designing a Building
Authors: Jeong Young Sun
Published: April 2015

Building designs should be reviewed from the aspects of both design aesthetics and energy performance. The installation of insulation materials in external walls, roofs, and floors is a basic method that could reduce energy losses from buildings. The purpose of this study is to investigate the types of insulation materials selected as building materials and the insulation performance of each building elements when designing new buildings in South Korea. The insulation performance of the external walls, roofs, and floors of buildings were compared with the insulation criteria of the Energy Saving Design Standards of Buildings in building energy code. The design documents, as well as drawings and building energy saving plan sheets, which are required to be submitted for buildings larger than a certain size in South Korea, were collected. The most widely used insulation material in multi-family housings and non-residential buildings was extruded polystyrene (XPS). The insulation performance of external walls, roofs, and floors were higher than that established by design criteria of building energy code. In particular, the external walls had roughly a 25.5% better insulation performance than the insulation criteria.
Influence of the Installation Lines to the Acoustic Properties of Dividing Wall
Authors: Winkler Jiří , Kubeckova Darja , Kucerova Lucie , Zdrazilova Nada
Published: April 2015

This article presents the results of long-term research of airborne sound insulation of a dividing wall. Specifically it shows how strong effect on the acoustic properties of the dividing walls has the line installation of technical equipment of building. The experimental structure was built from shaped hollow bricks where the influence of structural damage is in terms of the noise propagation essential. This type of structure was selected because it is one of the most commonly used structural systems and the acoustic properties are still neglected aspect.
Improvement of Acoustic Properties and Dynamic Characteristics of Temporary Bridge Structures
Authors: Skotnicova Iveta , Zdrazilova Nada , Fojtik Roman , Oravec Pavel
Published: April 2015

The article deals with dynamic and acoustic characteristics of the temporary steel bridge structures. Their construction is usually associated with the need of temporary replacement of the permanent bridge structures which were damaged or completely destroyed due to natural disasters or by human forces during the military operations or terrorist attacks. If some area is affected such this disaster, it usually gets into the difficult economic situation and it is not possible to recover the permanent construction in real time. In many cases there arises a situation that the temporary structure performs its function for years or permanently. In view of this fact, it is necessary to solve a number of defects, especially with regard to the long-term dynamic stresses in the structure and to excessive noise, which arises due to the traffic, because this structure is not primarily designed for it.
Analytical Homogenization for In-Plane Shear and Torsion of Honeycomb Sandwich Plates with Skin and Height Effects
Authors: Li Yu Ming , Hoang M.P. , Abbes Boussad , Abbes Fazilay , Guo Ying Qiao
Published: April 2015

Numerical modeling of honeycomb structures is too tedious and time consuming. The homogenization of these structures enables to obtain an equivalent homogeneous solid and its elastic stiffness thus to make very efficient simulations. In the present study, the skin effect is taken into consideration for the in-plane shear and torsion problems, in which the two skins are much more rigid than the honeycomb core. An analytic homogenization method, using trigonometric function series and based on the membrane plate theories, is proposed to study the influence of the honeycomb height on these properties, and the upper and lower bounds of the equivalent elastic stiffness of their curves are analyzed. A numerical H-model is established for the in-plane shear and torsion problems.
The Design and Research of Automatic Micro-Pressure Relief Valves Used in Mine Rescue Cabin
Authors: Zhou Nian Yong , Jiang Yan Long , Xu Lei , Li Jun , Wang He Xu
Published: April 2015

By analyzing the key technologies of pressure relief valve and comparing the advantages and disadvantages of existing products, liquid sealing automatic micro-pressure relief valve is designed with the properties of adjustable opening pressure, fast response rate, good sealing performance and long life, etc. Also, a reasonable mathematical model of liquid sealing automatic micro-pressure relief valve is developed, and the pressure relief valve’s opening pressure, reset pressure, relief rate and other key performance parameters is obtained. This work wil be helpful for the design and research of automatic micro-pressure relief valves used in mine rescue cabin.
An Innovative Method of Harnessing Hydraulic Energy for Mini Cost-Saving Water Treatment Plant Using Hydraulic Turbine: A Mathematical Approach towards Design and Analysis
Authors: Talib bin Din Abdul , Kher V.K. , Tan Chee Fai
Published: April 2015

River pollution has been a well-known worldwide issue and the impacts of polluted rivers are greatly affecting the health well-being of people worldwide. Meanwhile water treatment plants (WTP) have increasing energy cost. However, an abundance of hydraulic energy is stored in the flowing river water. The hydraulic energy can be harvested to be converted into mechanical energy to operate the WTP. This paper is focused on explaining an efficient and green method to harvest hydraulic energy to reduce the energy cost incurred by the usage of motorized equipment in conventional WTP. This product has dual purpose with dual benefit of restoring the quality of river water quality as well as harvesting readily available hydraulic energy to reduce energy cost.
Investigation of Sensitivity Effect Based on Mass and Stiffness Modification in Automobile Crankshaft
Authors: Zetty R.M.S. , Aminudin B.A. , Aung L.M. , Khalid M.K. , Norfazrina H.M.Y. , Raihan N.M.R.
Published: April 2015

A modeling through sensitivity analysis is one of the promising methods to investigate the dynamic characteristics of complex mechanical parts. This study aimed to investigate the effect of sensitivity based on mass and stiffness modification in automobile crankshaft as a function of natural frequency. Verification for the crankshaft model that is used in the experiment and simulation was done and both results showed good agreement and small errors percentage. The modification was also done by reducing the different percentage of crankshaft’s mass and stiffness. Partial differential analysis was used in the sensitivity analysis in order to figure out the natural frequency after every set of modification. According to the results, we also found that there were changes of sensitivity value by changes in mass value but the stiffness value remains unchanged. However, there is no significant effect of stiffness reduction on vibration was found in this research.
The Effects of Fluid Structure Interactions on the Dynamic Characteristics of the Reactor Internals Structure of SMART
Authors: Lee Jang Won , Lee Young Shin
Published: April 2015

The Korea Atomic Energy Research Institutes has been developing the SMART (System integrated Modular Advanced ReacTor), an environment-friendly nuclear reactor, for the generation of electricity, and to perform desalination. SMART reactors can be exposed to various external and internal loads caused by seismic and coolant flows. Reactor structures need to be maintained for the reactor’s safety and integrity against these loads during the operational time of the SMART. This paper presents two FE-models, 3-D solid models of the reactor internals in the air and in the coolant, and then compares the results of the dynamic characteristic for the two FE-models using a commercial Finite Element tool, ANSYS V12. A solver was selected by the Block Lanczos method. These FE-models are looking forward to being executed in various researches concerning the SMART in further studies.
Visualized Flow Structure inside an Odor-Removing Basin System with Multi-Stacked Porous Baffles
Authors: Lee Woo Hyeong , Kim Kyung Won , Lee Jae Heon , Yoon Jong Hwan , Kwak Moon Kyu , Park Cheol Woo
Published: April 2015

Baffles are frequently used to reduce flow speed and to change fluid passages by directly blocking oncoming flow. This study employed multi-stacked porous baffle obstructions to enhance the flow relaxations of water-soluble buoyant gases inside an odor removing basin system. We performed qualitative flow visualization by using tracing particles in working fluid to evaluate the effects of porous baffles. Particle image velocimetry technique was also employed to quantitatively analyze the flow field around the baffle regime. As a result, oncoming two-phase bubbly flow from the basin bottom regime was bent, passing the edge of a porous baffle plate. The main stream speed and momentum were effectively reduced by the installed porous flow obstruction devices.
Embedded Wireless Automatically Watering Plants Using UAV
Authors: Subpratatsavee Puchong , Kuha Peeyawal , Pudtuan Peerapon
Published: April 2015

In this paper is intended to study and develop embedded systems for use in controlling the operation of the Unmanned Aerial Vehicle (UVA) to work effectively under automatic control system. As well as to design flight control 4 blades, which uses an ATmega328 microcontroller controls the four motors and fly under equilibrium conditions. The embedded system is defined boundary conditions for UAV to suit the operation of the UAV. The Wi-Fi signal is used to transmit data in order to bring the instruction set processor to control the operation of UAV and displayed to the user immediately. Operation of the UAV based on the conditions that were set by the user to suit the scope of work that user need. Nowadays, high technology machines and robots for use in agriculture is very much in some areas. In order to reduce the work of human and still operates efficiently as well. Thus was born the idea to put apply including embedded systems and robotics in order to be used in agriculture to function effectively. Appropriate to the environment and work under human control.
Path Control for a Manipulator while Tracking a Given Trajectory
Authors: Lezhnina Yuliya A. , Ternovaya G.N. , Petrova I.Yu.
Published: April 2015

The paper propose to use robust control algorithm with disturbance compensation for management anthropomorphic robot PUMA type so as to ensure the movement of the robot manipulator along a predetermined path with a given accuracy. Necessary to generate a control signal for each degree of mobility without the use of velocities and accelerations of its relative coordinates measured output variables or other degrees of freedom. Thus, decentralized control is implemented to overcome the handling robot. For the formation of the control actions using the auxiliary circuit. This approach allows compensating for structural and parametric perturbations of the control object.
The Influence of Bone Cement Mixture Characteristics on Orthopedic Surgery
Authors: Liu Chien Wei , Wang Ching Sung , Wu Po Ching , Lo Chia Chi , Fang Chiang Lu , Kwok Tiew Guan
Published: April 2015

An important breakthrough of orthopedic surgery is to use bone cement to fill the space between an artificial joint and bone tissue, which allows the artificial joint to stabilize on human bone tissues. However, surgery failure cases due to bone cement utilization and side effects still exist at present. Therefore, the purpose of this study is to investigate bone cement characteristics, such as coagulation time, consolidation time, maximal exothermic temperature and anti-compressive strength, etc. under different mixture ratios. Our results showed that the smaller the ratio of polymethyl methacrylate and methyl methacrylate (PMMA/MMA), the lower exothermic temperature and the stronger anti-compressive resistance. These results are helpful to reduce incidences of post surgery side effects. Of note, bone cement supplement decreases corresponding to loading and operating time, which will become a major challenge for orthopedic surgery.
Solutions with Bessel Functions on Diffusion Modeling in Relation with Distance
Authors: Riza Ion , Popescu Marius Constantin , Opran Constantin Gheorghe
Published: April 2015

The diffusion phenomenon is widely spread in nature and bears a special importance for corrosion. Corrosion can have an impact on equipment and installation safety, from simple steel objects to nuclear reactors. As a result, it is extremely important to study corrosion and, indirectly, the phenomenon that sustains it, namely oxygen diffusion. The current paper analyses the mathematical model of diffusion based on differential equations. In this paper we use the diffusion that depends on a distance through a negative exponential function in order to explain the decrease of oxygen concentration, starting from the interface with atmosphere towards the inner layers of the oxides. The increase of the precision of the mathematical model can be done by adding new differential terms.
γ-Irradiation Induced Synthesis of Titanium Dioxide/Poly(acrylic acid) (TiO2/PAA) Nanocomposites and Layer-by-Layer Assembly on Glass Substrate
Authors: Trinidad Lawrence John Paulo L. , Usman Ken Aldren S. , Payawan Leon M.
Published: April 2015

Adsorption and encapsulation of the nanoparticles in polyelectrolytes impart stability to the nanometal by preventing aggregation through electrostatic and steric effects. Poly (acrylic acid) (PAA) was employed as a polymer cap to anatase titania nanoparticles. Cross-linking of the polymer was done via free-radical cross-linking using gamma-irradiation. The size of the nanocomposite produced ranged from 40-120 nm. SEM images showed that excess TiO2 in solution becomes nucleation sites for aggregation. Film assembly of the synthesized nanocomposite were done by layer-by-layer deposition with PDDA. Films formed with increasing thickness (5, 10, and 15 layers) were analyzed under AFM and shown to have a thickness of 0.25 μm, 1.1μm and 3.0 μm respectively.The average film layer thickness obtained ranged from 50-200 nm per TiO2/PAA-PDDA layer where as the number of layers deposited increase, the layer thickness increase while the roughness decreases.
Structural Study of Iron Oxide Thin Films Using Pre-Edge Feature of XANES
Authors: Dehipawala Sunil , Samarasekara Pubudu , Dahanayaka Rasika
Published: April 2015

Recently there has been a very high demand for small scale magnetic storage devices. The industry sector has consistently demanded sub micron or even nanometer scale magnets. Magnetic thin films often contain several layers of coating. For the purpose of this study, we prepared thin film magnets by spin coating a precursor containing iron into a glass substrate. The thickness of the films was controlled by the spin rate. Precursor films on the substrate were then annealed to 6000 C for 3 hours in air. The micro structure of iron in the films was investigated using the pre-edge feature that appears in the X-ray Absorption Near Edge Structure (XANES) for samples containing different iron layers. The main absorption edge peak position and pre-edge energy position were identical in all of the samples. This indicates that there was no change in the charge state of the iron regardless of the number of layers. However the intensity of the pre-edge feature decreases as number of layers increases which shows a decrease of Fe-O compounds as the number of layers increases.
Synthesis and Characterization of Poly(Glycerol Sebacate)-co-Lactic Acid via Gamma Irradiation
Authors: Dupio Michael Giles B. , Nunez Gandy M. , Abad Lucille V. , Aranilla Charito T. , Magdaluyo Eduardo R.
Published: April 2015

The gamma irradiation was utilized to facilitate the synthesis of poly (glycerol sebacate)-co-lactic acid (PGS-co-LA). The effect of methyl methacrylate (MMA) crosslinker and varying dosage of irradiation to the structural composition and thermal properties of the synthesized PGS-co-LA was investigated. Compositional analyses of the polymer materials using infrared spectroscopy confirm the covalent formation of ester linkage. The use of methyl methacrylate enhances the formation of the characteristic bonds in the polymer structure. The intensity of these peaks increases with increasing irradiation dosage and high amount of crosslinker. The melting temperature of the PGS-co-LA becomes more negative with the incorporation of high amount of MMA.
Production of Amorphous and Crystalline Silica from Philippine Waste Rice Hull
Authors: Mirasol Emie Salamangkit , Cervera Rinlee Butch M.
Published: April 2015

Rice husk is the covering of rice seeds and a by-product of milling rice grain. This study is conducted to investigate the production of silica (SiO2) formed from waste rice hull (RH) at different processing temperatures and study its structure, morphology, and thermal properties. Thermal analysis by thermogravimetric analysis (TGA) of the dried RH showed two mass-loss steps associated to the moisture desorption and thermal decomposition. Powder X-ray diffraction patterns of the rice hull calcined at 550 oC showed a purely amorphous SiO2 structure while those calcined for 900 oC for 1 hour and for 3 hours showed a glass-ceramics and crystalline SiO2 structure, respectively. This structural result is supported by the results obtained from the FTIR and Raman analyses of the samples. On the other hand, the Scanning electron microscopy (SEM) images showed the morphology of the samples revealing an increasing particle and grain size of the samples calcined at higher temperatures and longer heat treatment duration. In addition, Energy dispersive X-ray (EDX) spectra of both amorphous and crystalline SiO2 samples confirm that the sample contains mostly silicon and oxygen. Thus, in this study, the desired form of either amorphous or crystalline SiO2 from waste rice hull can be successfully obtained by controlled heat treatment.
Influence of the Structure of Glycidyl Methacrylate Copolymers on the Hydrophobic Properties of Cellulose Materials
Authors: Bryuzgin Evgeny , Klimov Victor , Zaytsev Sergey , Navrotskiy Alexander , Novakov Ivan
Published: April 2015

The modification of the surface of cellulose-containing materials by copolymers of polyglycidyl methacrylate (PGMA) obtained by means of two ways: acylation of PGMA by stearic acid and copolymerization of glycidyl methacrylate and lauryl methacrylate is proposed. It is demonstrated, that the use of obtained copolymers allows to get the superhydrophobic coatings on the surface of cellulose-containing materials with reaching of contact angles up to 161°. Such modified materials can be used as filters for the separation of the water-oil emulsions.
A New Reverse Engineering Method for the 3D Surface Reconstruction without Contact
Authors: Giraud-Moreau L. , Slysz R. , Borouchaki H.
Published: April 2015

In this paper, a new reverse engineering method is proposed for 3d surface reconstruction without contact. This method is based on the combination of stereovision and structure light methods. The originality of the proposed technique is that the pattern is a two-dimensional Delaunay triangulation. A key characterizing the vertices is computed for each vertex. The pattern matching between two images is reduced to the comparison of two meshes. The three dimensional triangulation of the surface can then be obtained by using the geometric properties of the acquisition devices.
Numerical Simulation of Composite Hemp Fibers Behavior for Aircraft Application
Authors: Cherouat Abel , Montay Guillaume , Ilczyszyn Florent
Published: April 2015

Hemp fibres are using as reinforcement for compounds based on polymer in different industrial manufacturing (aerospace and automotive) for their interesting mechanical and ecological properties. The hemp fibres present a non-constant cross section and complex geometry that can have a high effect on their mechanical properties. In this study, a micro-traction test coupled with a numerical imaging treatment and a finite elements method are used. The mechanical tensile test allows to determinate the evolution of the traction load in function of the displacement until the fibre crack. The used fiber are incorporate in plastic material is order to obtained PP/hemp reinforcement composite part. Static and dynamic tests are proposed in order to study trhe behaviour of green material subjected to tensile load.
Modeling the Residual Stress in Woven Thermoset Composites Parts for Aerospace Applications Using Finite Element Methods
Authors: Nawab Yasir , Park Chung Hae , Saouab Abdelghani , Agogué Romain , Beauchêne Pierre
Published: April 2015

Process induced residual stresses in thermoset composite parts is one of significant issue faced by the industry. Its Modelling is a coupled multiphysics phenomena. Precise information about the chemical shrinkage, thermal expansion coefficient, cure kinetics, heat transfer and constitutive equation are required for an accurate simulation. In this article, spring-in angle induced in woven carbon/epoxy composite bracket is modelled by solving the thermo-kinetics and thermo-mechanics coupling simultaneously in a commercial finite element software. The obtained values of spring-in angle using numerical simulation are compared with those found in the literature and both are found in agreement.