bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Microstructural Properties of PAN/MnO2 Nanofibers via Electrospinning Method
Authors: Binti Yusof Norhaniza , Affandi Ieqmal Emeer , Abdullah Norfadhilatuladha , Ismail Ahmad Fauzi , Jaafar Juhana
Published: April 2015

This paper reported the production of precursor PAN/MnO2 nanofibers via electrospinning method and studying its microstructural properties. The nanofibers were prepared by electrospun the polymer solution of polyacrylonitrile (PAN) and Manganese Oxide (MnO2) in, N, N-Dimethylformamide as its solvent. The factors considered in this study were polymer PAN/ MnO2 concentration which will significantly affect the specific surface area, nanofibers morphology, micropore volume and diameter of the nanofibers. The nanofibers were characterized using Scanning Electron Microscopy (SEM), Brunauer Emmett and Teller (BET) surface area, and Fourier Transmission Infrared Spectroscopy (FTIR). The addition of MnO2 in polymer solution increased the specific surface area of the nanofibers up to 3.5 wt % which found to be its optimum loading. In conclusion, the precursor PAN/ MnO2 -based ACNF were successfully produced with the optimization of metal oxide loading resulting to nanofibers with higher specific surface area which will further increased its adsorption performance.
Reliability Evaluation of Optical Fiber Protection Channels Based on Practical Coding and Logical Calculation
Authors: Fang Bi Wu , Liu Di Chen , Wang Bo , Ye Xiao Li , Jia Jun , Bian Chen Zhi
Published: April 2015

To solve the reliability assessment challenge of protection channels caused by elements multiplexing. The paper build a weighted-undirected graph of optical fiber protection channels, whose nodes measurement is SDH reliability and reliability of optical fiber as edge weights. Start from the information provided by the actual grid, encode the data according to the most close to the actual data format, developed an algorithm for channels and services reliability assessment based on logical "or" and "exclusive or". The result is verified in a 9-node and 19-channel network in central China Grid, showing that the proposed encoding method and model have good practicability and operability, which can offer grid reference to network optimization, scientific channels arrangement and the maintenance of the protection channels.
Transient Instantaneous Voltage Sag of Distributed Generation Bus in Muangxay Substation, Oudomxay Province, Laos
Authors: Phothilath Khamhyo , Tonmitr Kittipong , Artrit Pramin
Published: April 2015

This paper presents the transient instantaneous voltage sag analysis of distributed generation (DG) in distribution system. The behavior of voltage sag is analyzed by using DigSILENT power factory software (DPFS). As affected by unsymmetrical fault of feeder 2, the calculation of initial condition carries out through instantaneous values (electromagnetic transients). The simulation results show that instantaneous voltage sag affects the DG and operation of electrical equipment. The phase short circuit affects the voltage waveform, varies from the original waveform and caused the flicker transient problem.
A Comparative Study on the Noise between Floors of Apartment and Multiplex Housing
Authors: Kim Ji Hun , Shin Yoon Seok
Published: April 2015

Since recently almost all housing built in Korean have shared walls and floor, diverse problems are unavoidable including noise between floor arising from noise and vibration. Many efforts have been made by the Korean government, but the number of complaints related with the noise between floors has been gradually increasing. Therefore, through the field measurements by house type, the current state of noise was understood. To do this, the noise between floors was measured in an apartment household and a multiplex house to perform a comparative analysis. As the result, the differences in the noise between the two house types were clarified. The findings of this research are expected to contribute to reduction of the noise between floors in an apartment building in the future.
A Safety Management Method Based on Job Stress Analysis for Foreign Construction Laborers in Korea
Authors: Shin Yoon Seok
Published: April 2015

In Korea, construction accidents have been constantly increasing. Construction laborers have higher hazard rates and higher work intensity than other industries, which mean that they experience more job stress. The job stress has risk to have a negative impact on their safety at site. While the number of foreign laborers has increased, there are few studies about the stress of them. Therefore, this study proposed a safety management method based on job stress analysis for foreign construction laborers in Korea. A questionnaire to measure job stress was performed targeting foreign laborers, and the results were analyzed. The results of this study can be utilized to preventing construction accidents related to job stress in the future.
Application of Finite Element Analysis to the Interface Decohesion of CFRP/SMA Composite
Authors: Kim Noh Yu , Young Sung
Published: April 2015

In this work, finite element calculations were carried out to simulate wire pullout process of the shape memory alloy (SMA) wire/carbon fiber reinforced polymer (CFRP) hybrid composite. Three-dimensional cohesive zone model was used for the bonding interface between the SMA and the CFRP. Phase transformation behavior of the SMA wire was accounted for by using a multi-variant constitutive model. The numerical parameters were fitted using an experimental measurement reported by Jang and Kishi. Young’s modulus of the wire affected the force vs. elongation curve most effectively. It is shown that the actual shear stress profile is not constant but it varies significantly along the axial direction of the wire. Additional toughness due to the SMA wire was higher than the case of a purely elastic wire, and the toughness increment was approximately 21 kJ/m2. This value is comparable to the typical toughness value of CFRP.
Simulating Migration Properties of Aquifer Disposal of CO2 in Western Taiwan Basin
Authors: Tseng Chien Hao , Su Wei Chih , Kuo Chia Chen , Lai Chuan Lin
Published: April 2015

Geologic sequestration of carbon dioxide (CO2) in deep saline aquifers is one of the most feasible techniques for mitigating the greenhouse effect. However, over-optimistic design of CO2 injection scheme may adversely overwhelm the sealing capability of the cap-rock in the saline reservoir. In this study, we have developed a complex three-dimensional heterogeneous model to study the spatial and temporal distribution and storage of CO2 injection into the saline aquifer structure at Taiwan western offshore. For investigating the mechanisms of CO2 migration in a deep saline reservoir, which was hypothesized as a sequestration site, the result of numerical simulations was analyzed. Numerical simulation of CO2 migration in geologic formations can provide key information for predicting CO2 plumes before conducting field-scale operations or pilot tests. In order to avoid the problems of overpressure in the saline reservoir, the case study employs multi-well injection strategies. The sensitivity analyses based on the two different injection strategies in the western sea of Taiwan show that the locations of CO2 plume front might be from hundreds of meters to kilometers.
A Security of Circular Email in Manufacturing
Authors: Subpratatsavee Puchong , Chintho Chanchira , Tanaiadehawoot Suchai
Published: April 2015

In present, manufacturing organizations in some countries will have to submitinformation to both internal and external to the organization, called circular mail to report newswithin the organization or external relations. Administrative officer is responsibility about to senda circular mail for each organization and will be responsible for receiving letters in paper form orpublication or media message. Then the administrative officer will be read and extracted the letterand send a message in the form of emails to receivers as indicated on the letter. In mailings sendsuch potential attacks from disgruntled individuals; such as a change of email messages duringtransmission or identity thieves use a fake email address to send officials to the other party. If anattack occurs, the organization will make a loss. In terms of stability credibility and security in theuse of corporate email. This paper presents a model and how to send an email or letter online ina format that is more stable and secure by the applied technology of public key cryptography andhash function to encrypt the message to provide stability and security in the mail's circulars online.
Influence of Irradiation Doses on Mechanical Properties of Glass Fiber Filled PBT
Authors: Kratky Petr , Manas David , Manas Miroslav , Stanek Michal , Ovsik Martin , Senkerik Vojtech , Navratil Jan
Published: April 2015

The submitted paper compares mechanical properties of the hard surface layer of modified PBT filled by 35% of glass fibers. Hard surface layer was made by radiation cross-linking technology which allows polymer materials modification followed by the change of their end-use properties. The surface layer of polymer material is modified by β – radiation. When the polymer material is exposed to the β – radiation, it is possible to observe changes of the surface layer at applied load. The mechanical properties were measured by nanohardness test with using the DSI method (Depth Sensing Indentation).
Study for Development Directions and Real Application Cases of Korea Production System (KPS)
Authors: Kim Chong Man , Lee Jeong Cheol , Choi Seong Woo
Published: April 2015

This research introduces KPS (Korea Production System), which is a type of manufacturing innovation methodology. The KPS has been developed by KPC (Korea Productivity Center), which is a special corporation with the objective of industrial productivity improvement. In this paper, we show theoretical validity of the KPS, in which there are 6 principles (People Involvement, Field Standardization, Continuous Innovation, Flexibility of Production, Commercialization of production Information) and thirty core activities based on the above 6 principles, and the KPS has a list of 140 assessment items for evaluations of the above core activities. In addition, we summarize some differentiations between the KPS and other manufacturing innovation methodologies. During the past three years, the KPS has been used in productivity innovation partnership program between major companies and SMEs (small and mediums-sized enterprises) in Korea. In this program, the KPS has been applied in production lines of various SMEs, which are almost cooperative firms of global and major companies such as Samsung elec., POSCO, LG elec. and so on. To show the effectiveness of the KPS, we introduce outcomes of some real implementation cases in the production lines of SMEs, finally.
Hybrid Knowledge-Based System for Collaborative Green Automotive Manufacturing Management
Authors: Mohd Nawawi Mohd Kamal , Nik Mohamed Nik Mohd Zuki , Adli Aminuddin Adam Shariff
Published: April 2015

The objective of this research paper is to demonstrate the application of hybrid knowledge-based system, gauging absences of pre-requisites (GAP), and analytic hierarchy process (AHP) approaches for selecting the improvement programs for Collaborative Green Manufacturing Management (CGMM) system. In this research, a generic knowledge-based system is developed to measure the level of CGMM adoption in automotive manufacturers compared to the ideal system. Using the GAP and AHP tools, the key green manufacturing improvement programs can be prioritized and demonstrated with an illustrative example.
Quality Assurance of CIPP Liners According EN ISO 11296-4
Authors: Cigler Otakar , Kubečka Karel , Waldstein Petr
Published: April 2015

Using Cured-in-Place-Pipes for sewer renovation has developed to a common and widely used trenchless technology for pipes and especially sewer rehabilitation in different countries in last 20 years. This process was accelerated with the standardization of the CIPP liners and also due to intensive quality assurance which is highly developed especially in Germany. The quality control and quality assurance is generally ruled according EN ISO 11296-4 which is not fully sufficient as our research has shown.
Influence of Irradiation Doses on Mechanical Properties of PA6
Authors: Kratky Petr , Manas David , Manas Miroslav , Stanek Michal , Ovsik Martin , Skrobak Adam , Reznicek Martin
Published: April 2015

The presented article deals with influence of mechanical properties of the hard surface layer of modified polyamide 6. The mechanical properties were acquired by nanohardness test with using the DSI method (Depth Sensing Indentation). Hard surface layer was created by radiation cross-linking technology. This technology allows polymer materials modification followed by the change of their end-use properties. The surface layer of polymer material is modified by β - radiation. When the polymer material is exposed to the β radiation, it is possible to observe changes of the surface layer at applied load.
Mobile Factory Network (MFN) – Network of Flexible and Agile Manufacturing Systems in the Construction Industry
Authors: Rauch Erwin , Matt Dominik T. , Dallasega Patrick
Published: April 2015

The concept of the "On-site Factory" consists in the temporary use of fully functioning mobile mini-factories or production cells at the site of consumption. Mobile Factories are well suitable for situations in the construction industry with long distances and therefore high logistics costs. The advantage of this concept is its economic efficiency combined with a maximum of flexibility and a just-in-time supply. By a high degree of reconfigurability and scalability of the On-site Factory, it can be adapted to its individual mission and the quantity demand at the construction site. This research discusses the need for new and innovative JIT solutions for construction industry and addresses the specific case of networks of mobile on-site factories. The creation of a Mobile Factory Network (MFN) shows an interesting new and innovative business model for decentralized manufacturing on-site. The research shows a possible form of network structure and organization as well as its advantages and potential for the construction sector.
Traffic Simulation at Intersections with Cranked Priority
Authors: Krivda Vladislav , Petru Jan , Mahdalova Ivana , Skvain Vaclav
Published: April 2015

The article deals with problems of traffic simulation at cross intersection with cranked priority. For traffic simulation was used microsimulation software PTV VISSIM. In the article there is shown the brief description of traffic model creation and results of evaluation of travel times and delay times occurring during transit through the observed intersection.
Formation of High Aspect Ratio Nanostructures Using Focused Ion Beam Induced Deposition of Carbon
Authors: Ageev Oleg A. , Ilin Oleg I. , Kolomiytsev Alexei S. , Lisitsyn Sergey A. , Smirnov Vladimir A. , Zamburg Evgeny G.
Published: April 2015

This paper presents results of the formation of high aspect nanostructures by local deposition of carbon, stimulated by focused ion beam (FIB). The structures used in the modification of the probe sensors were cantilevers for atomic force microscopy (AFM). The FIB structure of 5 mm length and 50 mm radius of curvature formed on the surface of the cantilever tip has shown to improve the accuracy of measurement by AFM. The outcome of this study is useful for the development of manufacturing processes and modification of the probe sensor-cantilever AFM structures of field-electron emitters as well as in the studies of micro- and nanosystems technology.
Anisotropic Wetting Behavior on Injection Molded Polypropylene Parts Inspired by Surface Structure of Moss
Authors: Boruvka Martin
Published: April 2015

During the last years the carmakers interest is focused on polymer manufacturers to develop breakthrough solutions addressing the key drivers of reducing weight and cost. The use of polypropylene (PP) and other thermoplastic olefins is growing because of their low cost and good properties. Unfortunately, some of the same properties that make these plastics attractive to designers, also make them difficult to bond with adhesives or varnish. Non-polar character of PP results in poor surface properties and low wettability. Several methods of surface pretreatments have been used to improve its wettability, but all involves cost extending additional processing. Based on lessons from nature, one of the ways how to increase wettability is surface structuring. Injection mold insert designing and manufacturing process inspired by hydrophilic structure of the moss is presented. Due to cost reducing demands were used conventional processing methods.
The Liquid Condensation Conditions in the Dry Gas Seal System
Authors: Ma Ai Lin , Song Peng Yun
Published: April 2015

Dry gas seal is often used as the seal devices in centrifugal compressor and other high-speed rotating equipment, which requires seal gas clean and dry. If there is some liquid in the seal gas, the dry gas seal will rapidly fail. When the seal gas flows through the filters, valves, orifices, seal faces and so on, the gas temperature will decrease resulted from the Joule- Thomson effect. If the gas temperature is lower than the corresponding dew point, there will be liquid condensation in dry gas seal system. Wet air is taken as an example to show how to calculate the pressure and temperature relationship when it is adiabatic expansion. Dew point lines at different conditions are calculated by considering the vapor-liquid equilibrium. Liquid condensation conditions are acquired by comparing expansion lines and dew point lines, and the factors of influencing liquid condensation were analyzed. The results shows that decreasing gas humidity, increasing the gas temperature can effectively reduce the liquid condensation.
Corrosion of Fe-2.25Cr-1.6W-0.1Mo Steels in Na2SO4 Salts at 800 and 900°C
Authors: Yadav Poonam , Bak Sang Hwan , Lee Dong Bok
Published: April 2015

The ASTM T23 steel with a composition of Fe-2.25Cr-1.6W-0.1Mo in wt.% was corroded in the Na2SO4 salt at 800 and at 900°C, and its corrosion behavior was studied. It formed thick, porous oxide scales that consisted primarily of outer Fe-rich oxides and inner (Fe, Cr)-rich oxides. The corrosion of the T23 steel progressed mainly via oxidation.
Electret State in Composite Polymer Materials Based on Low Density Polyethylene and Polypropylene
Authors: Gorokhovatsky Yuri , Temnov Dmitry
Published: April 2015

The electret state stability in composite polymer materials based on polypropylene and polyethylene with various dispersed inclusions was investigated. It is shown that the surface potential relaxation time of a polymer increases significantly when hydrophilic inclusions are added into its composition. It is assumed that the surface potential relaxation in the initial films occurs due to the volume conductivity which is catalyzed by water molecules within the polymer volume. Introduction of hydrophilic inclusions decreases the volume conductivity of the films as a results of which the stability of their electret state increases.
Methylene Blue Adsorption onto NaOH Treated Leucaena leucocephala Leaf Power
Authors: Hanafiah Megat Ahmad Kamal Megat , Mansur Noor Fhadzilah , Wan Ab Rahman Wan Mohd Nazri , Ismail Mardhiah
Published: April 2015

The potential of sodium hydroxide (NaOH) modified Petai Belalang (Leucaenaleucocephala) leaf powder as a biosorbent for methylene blue removal from aqueous solutions was investigated. Adsorption parameters studied include initial dye concentration, pH, dosage, kinetics and isotherms. The pHzpc of chemically treated Leucaenaleucocephala leaf powder was 7.50 and adsorption equilibrium time was achieved after 60 min. The kinetic data was best represented by the pseudo-second order model. The maximum adsorption capacity predicted from Langmuir model was 208.33 mg g-1. This work indicated that NaOH treated Leucaenaleucocephala leaf powder can be an attractive biosorbent for MB removal from diluted industrial wastewater.
Corrosion of T92 Steels in Na2SO4 Salts at 800 and 900°C
Authors: Lee Dong Bok
Published: April 2015

The corrosion behavior of the ASTM T92 steel in the Na2SO4 salt was studied at 800 and 900°C. At 800°C, the T92 steel formed thin (Fe, Cr)-rich oxide scales, indicating a good corrosion resistance due to 9%Cr presented in the alloy. However, at 900°C, the T92 steel displayed poor corrosion resistance, because the scales dissolved off rapidly owing to the increased corrosion rate.
Residual Stress Effects on Fatigue Crack Growth in Directionally Solidified YAG/Spinel Eutectics
Authors: Abali Serkan
Published: April 2015

In this paper, yttrium aluminum garnet-magnesium aluminate spinel with good mechanical strength was fabricated by directional solidification, and its microstructure and mechanical properties were investigated. MgAl2O4-Y3Al5O12 eutectic rods were grown by a float zone method. The composition of the grown ingots was determined by the X-ray diffraction technique and electron probe microanalysis. The crack growth characteristics were examined in directionally solidified YAG/spinel eutectics. The residual stresses were determined in MgAl2O4/Y3Al5O12 eutectics using piezospectrosocopic probes. The crack growth behaviors show that residual stresses play a key role in the crack growth.
Study of Surface Segregation Defect of 7075 Aluminum Alloy in Semi-Solid Squeeze Casting
Authors: Umudee Nonanitta , Wannasin Jessada , Janudom Somjai , Canyook Rungsinee , Plookphol Thawatchai , Wisutmethangoon Sirikul
Published: April 2015

The objective of this present research was to study the surface liquid segregation (SLS) of 7075 aluminum alloy formed by semi-solid squeeze casting together with the gas induce semi-solid technique (GISS). The rheocasting times of 3, 5, 10, and 20 seconds, were used in GISS processes. The cross sectional areas of specimens near the mold were used to measure the surface segregation. The results revealed that longer rheocasting time gave higher amount of solid fraction in the semi-solid slurry. In addition, it was found that when solid fraction increased, the surface segregation increased.
Influence of Recycled Particle Size to Tensile Properties of Polyamide 6
Authors: Senkerik Vojtech , Stanek Michal , Manas David , Manas Miroslav , Skrobak Adam , Navratil Jan
Published: April 2015

The aim of this research is to show influence of particle size of recycled polymeric material to mechanical tensile properties. During grinding, the particles with various sizes are formed, from larger pieces to dust particles. This size variation can cause problems during subsequent processing. These particles of different sizes have distinct melting rate. That can cause an inhomogeneity of a melt and diverse structure of a solidified polymer. Several recycled mixtures with varied particle size after crushing were prepared. Tested polymer was polyamide 6 and the tests were performed at ambient temperature.
Recycling of Radiation Crosslinked Polyamide 6
Authors: Navratil Jan , Manas Miroslav , Stanek Michal , Manas David , Bednarik Martin , Mizera Ales
Published: April 2015

Growing usage of radiation crosslinked plastic materials and utilization of their advantageous properties might raise a question of their future recycling. This paper deals with utilization of recycled irradiated polyamide 6 (rPA6x) which is used as a filler into low and high-density polyethylene (LDPE/HDPE) in concentrations 10 and 30 %. Mechanical properties of such blends were investigated and compared. Both blends show similar trend at all observed material characteristics. Elastic modulus representing material stiffness grown with increasing amount of the filler. Ultimate tensile strength and impact toughness decreased and hardness slightly increased. All the obtained results show that it is possible to use recycled radiation crosslinked PA6 as a filler but it is necessary to count with properties change.
Surface Energy of Selected Polyolefins after Radiation Cross-Linking
Authors: Bednarik Martin , Manas David , Manas Miroslav , Stanek Michal , Navratil Jan , Mizera Ales
Published: April 2015

In this study there was found that radiation cross-linking increased the surface energy of high-density polyethylene (HDPE), and low-density polyethylene (LDPE). Surface energy affects the wettability of the surface and is very important for creating of high-quality bonded joints. The measurement results indicated that radiation cross-linking was a very effective tool for the improvement of adhesive properties and increased the surface energy of selected polyolefins. Surfaces of selected materials with ionizing beta radiation with doses of 0, 33, 66, 99, 132, 165, and 198 kGy were irradiated. The best results were achieved by irradiation at dose of 165 kGy. The surface energy after irradiation was increased up to 100 % compared to untreated material.
Corrosion of SUS 310 Steels at 600-800°C in N2/H2O/H2S Gases
Authors: Kim Min Jung , Lee Dong Bok
Published: April 2015

SUS 310 stainless steels were corroded at 600, 700 and 800°C for up to 30 h in 1 atm of N2/H2O/H2S-mixed gas. The formed scales consisted primarily of (Fe0.5Ni0.5)0.96S, FeNiS2, and FeCr2S4. They were fragile, porous, and susceptible to spallation. During corrosion, Fe, Ni, and Mn diffused outward, while sulfur and a lesser amount of oxygen diffused inward. The diffusion of Cr and Si was not conspicuous. The formation of sulfide scales and the presence of hydrogen and water vapor in the mixed gases made SUS 310 corrode fast.
Micromechanical Properties of Surface Layer of Electron Beam Irradiated of Glass-Filled PA6
Authors: Manas David , Ovsik Martin , Manas Miroslav , Stanek Michal , Fiala Petr , Bednarik Martin , Senkerik Vojtech
Published: April 2015

Micromechanical changes in the surface layer of glass-filled PA-6 modified by beta radiation were measured by instrumented test of microhardness. The specimens were prepared by injection technology and subjected to radiation doses of 0, 66, 99, 132 kGy. Measurements of microhardness showed considerable changes of behavior of surface layer in middle as well as high radiation doses with higher values of indentation hardness and stiffness.
Analysis of Materials Based on Inverse Modeling
Authors: Tomasek Pavel
Published: April 2015

This paper describes an interesting approach aimed at analysis of material properties. This work is based on simulated measurements of transmission coefficients of multi-layered materials. These measurements (in a waveguide) are taken as a product of a certain situation, therefore there is an inverse problem in which we try to estimate the original properties of the layers. This study employs analysis of closed-form solutions and numerical multi-parameter optimization.
The Evaluation of the Equations of State Used for the Joule-Thomson Effect Analysis in the Dry Gas Seal
Authors: Deng Cheng Xiang , Song Peng Yun
Published: April 2015

The Joule-Thomson (JT) effect will occur when the gas flows through the components of filters, valves, orifices and end faces in the system of the dry gas seal, which may cause the temperature of the seal gas to decrease, and even the emergence of liquid condensation. Generally, the Joule-Thomson effect is reflected by the Joule-Thomson coefficient. As to the hydrogen, nitrogen, carbon dioxide and air, which are often met in the dry gas seal, the corresponding Joule-Thomson (JT) coefficients were calculated by four classical equations of state (EOS) of VDW, RK, SRK and PR, which are compared with the experimental data in the literature. The results show that the JT coefficients calculated by RK equation are most close to the experimental data in the literature, whose relative error is lowest and less than 4%. When the JT effect of real gas in the dry gas seal is analyzed, the RK equation of state is recommend.
Surface Defects Formation in Grinding of Silicon Nitride Ceramics
Authors: Kuzin Valery V. , Grigoriev S.N. , Fedorov Sergey , Fedorov Mike
Published: April 2015

The effect of surface defects formation in grinding on two compositions of silicon nitride have been studied experimentally. The influence of composition of nitride ceramics, diamond wheels characteristics and grinding regimes on the grinding forces, final strength of samples and the degree of structure imperfection of their surfaces after grinding has been understood as a result of undertaken series of grinding tests.
Effect of Surface Shape on Light Absorption
Authors: Bilek Ondrej , Vašina Martin
Published: April 2015

This paper deals with influence of surface shape on light absorption. The study was performed on polyvinylchloride samples with different grooves. It was investigated the influence of shape, width, depth and number of grooves on light absorption. The investigated material samples were produced on CNC milling machine. Experimental measurements of light absorbance were performed under diffuse daylight on the basis of illuminance ratio. Different factors, that have influence on light absorption, are evaluated in the conclusion of this work. It was found that the lowest light absorbance was obtained in case of the smooth polyvinylchloride sample. The material machining causes multiple reflections of light from groove surfaces. For this reason the light absorbance of the groove surfaces is higher compared to the smooth material sample.
The Development of Bi-Ag Sandwich Sheets for Fire Assay Applications
Authors: Ruethaitananon P. , Praphairaksit Narong , Wongpreedee Kageeporn
Published: April 2015

A Fire assay is method to verify the fineness of gold with use lead in its process. In this research, Bi-Ag sandwich sheets for a lead-free fire assay method were developed. Bi-Ag sandwich sheets were produced by a hot-dipping method at temperature 300 °C and 400 °C. Samples were characterized the microstructure by SEM along the process. A fire assay method was used to verify and correlate the results of gold fineness to various kinds of wrapping sheets which are Bi-Ag sandwich sheets and lead. The Bi-Ag sandwich sheets shows the layer of 14-20 µm at 300 °C and 8.5-10.5 µm at 400 °C. After cupellation process, the metal beads were observed by SEM and mapping techniques to analyze the remained copper. XRF characterization was confirmed the results of compositions showing an increasing amount of copper as increasing temperature dipping on Bi-Ag sandwich of 0 wt%, 1.58 wt% and 1.34 wt% at S1, S2 and S3, respectively. Higher amounts of copper left on bead buttons consisted with the accuracy of fire assay results which were S1, S2 and S3 obtaining 99.99 wt%, 99.87 wt% and 100 wt% of gold, respectively.
The Analysis of Temperature and Strain Rate Influence on Flow Stress of Mg Alloy AZ31
Authors: Kapustova Maria , Balážová Mariana
Published: April 2015

This contribution analyses influence of thermo mechanical conditions of magnesium alloy - type AZ31 forming on its flow stress. Temperature and strain/deformation rate belong to the essential thermo mechanical parameters of strain/deformation process. A testing cylinder made of selected Mg alloy was strained using pressure at warm temperatures within defined two degrees of nominal strain 30% and 60% and strain rate of 5 s-1. The pressure test at warm temperatures was conducted at testing temperatures 250, 300 and 350°C. It is important to explore the temperature influence on AZ31 alloy flow stress in order to reduce energy consumption of formed pieces production. Surface quality and precision of required dimension will improve, as well. The experiment was aimed at graphic evaluation of temperature influence on flow stress of Mg alloy AZ31B. Resulting form flow stress curve it is possible to read out its value for particular strain. These values are essential for calculation of forming force and work. For magnesium alloy AZ31 warm forming at temperature interval of 230 - 425°C is typical. The pressure tests were realized within the temperature interval of 250 - 350°C, i. e. at temperatures belonging to lower limit of recommended temperature interval, with the aim of acquirement as much information as possible on Mg alloy behavior at low forming temperatures.
Femtosecond Ti:Sa Laser Processing of Silica
Authors: Babiy Michael , Biryukova Yuliya , Golik Sergey , Lisitsa Vladimir
Published: April 2015

The result of direct ablation of silicon by an 800 nm Ti:Sa femtosecond laser pulses are presented. Obtained slice of silicon with submicron roughness with tilt focused femtosecond laser pulses. Yaw cut more due to mechanical vibrations of the entire installation on a pneumatic table, but not the physics of the ongoing process. During processing, possibly thinning the silicon sample from the opposite edge (sharpening) to submicron values ​​(tens of nanometers).
Surface Modification of Zirconia (Y-TZP) Ceramics Induced by Pulsed Laser Machining
Authors: Kuzin Valery V. , Grigoriev S.N. , Fedorov Mike , Portnoy Mike , Ermolin Victor
Published: April 2015

Technological features of pulsed laser machining of yttriastabilized tetragonal zirconia polycrystal (Y-TZP) were studied. The connection between the laser power, scanning speed, laser beam steps and surface state of zirconia ceramic was established. The results of the research showed that pulsed laser machining of this material is an effective tool to control surface modification process and presents an attractive alternative to conventional techniques.
An Effective Jig for Friction Stir Welding of Pipe Butt Joint
Authors: Ismail Azman , Awang Mokhtar , Rojan Mohd Afendi
Published: April 2015

A dedicated or specialized friction stir welding (FSW) machine is quite costly especially for pipe joining. Therefore, not many institutions manage to conduct their research on FSW at their facilities. Besides that, the difficulty to design a jig that can hold the complex shape such as pipe section tightly and easily to be removed during and after the FSW process respectively will nullify the intentions. In many institutions, there was either conventional or CNC milling machine available in their workshops. Thus, a jig called orbital clamping unit (OCU) was designed to suit this milling machine. It acts as an additional device to enable this milling machine to run as FSW machine at a lower cost, hence fully utilized the available facility in the workshop. Several good samples were successfully produced by using this jig and milling machine
Structural Behavior of Reinforced Rubbercrete Beams in Shear
Authors: Mohammed Bashar S. , Loong Raymond Cheng Hsien
Published: April 2015

Rubbercrete is a concrete containing crumb rubber as partial replacement to fine aggregate. Advantages of rubbercrete have been reported by many researchers. In contrast to normal concrete, rubbercrete is a more ductile which can be used in areas prone to earthquake. In this paper seven reinforced rubbercrete beams without shear reinforcement are fabricated and tested up to failure. Three parameters are considered: beam width, effective depth and a/d. The experimental results are then compared with available shear quations. Available shear quations have produced conservative shear stress prediction for the reinforced rubbercrete beams.
Monitoring the Degradation of UHPC Boards
Authors: Kostelecká Michaela
Published: April 2015

In this article the hot water test is presented on thin UHPC slabs that are reinforced by a new type of armature. It is a textile armature, which should replace the classic metal (steel) armature. Textile armature should not only reduce the cost of production, but, because it is not susceptible to corrosion as conventional steel armature, panels can be designed with significantly less cover thickness in achieving similar or longer lifetime of these elements. The combination of UHPC concrete with a minimum thickness of cover and textile armature allows design elements weighing up to 70 % lower compared to conventional concrete elements with conventional armature. This can achieve significant savings and benefits not only in economic aspects, but also in environmental aspects.
Flexural Behavior of GFRP RC Beam Strengthened with Carbon Fiber Reinforced Polymer (CFRP) Plate: Cracking Behavior
Authors: Salleh Norhafizah , Mohd.Sam Abdul Rahman , Mohd Yatim Jamaludin
Published: April 2015

There has been much research conducted on the current performance of Fiber Reinforced Polymer (FRP) as reinforcement. It was due to FRP easier to maintain than steel during construction because of less weight. Laboratory works on the flexural behavior of concrete beams that with GFRP and CFRP use as a plate strengthening for the beam size 2800 x 200 x 250 millimeter. study of the pattern of cracking and failure modes of the beam will be compared between the ten types of beams consisting of steel reinforced beams , beam-reinforced GFRP and GFRP reinforced beams strengthened with CFRP with different lengths. Comparing between the beam bending performance was examined through the ultimate load, cracking and failure modes.
Application of Grid Approximation Method for the Calculation of Monolithic Reinforced Concrete Frame Taking into Account Construction Sequence and Concrete Creep
Authors: Zavyalova O.B. , Shein A.I.
Published: April 2015

The algorithm taking into account the concrete creep and changes of its modulus of instantaneous elasticity is defined. Such algorithm was based on formulas obtained by Harutyunyan (Harutyunyan, 1952). The program with the time factor taking into account both the specified events and the sequence of frames erection in a monolithic design was made.
Improved Surface Integrity during End Milling AISI 316L Stainless Steel Using Heat Assisted Machining
Authors: Alkali Adam Umar , Ginta Turnad Lenggo , Abdul-Rani Ahmad Majdi , Fawad Hasan
Published: April 2015

Different heat source had been investigated for thermally enhanced machining on various engineering materials. Even so, temperature control from the heat source remained a challenged to the process effectiveness.This study used oxyacetylene combustion flame as a heat source in heat assisted machining. The study focuses on the relationships between process conditions; maximum temperature distribution and the surface integrity of 316L stainless steel during preheat machining as compared to dry hard part machining. Two levels of cutting speed 1000rev/min, 630rev/min and feed rates 160mm/min and 100mm/min were investigated while the depth of cutting was maintained constant at 1mm. While preheat machining for 60seconds along the span of the work piece material at cutting speed 1000 rev/min and feedrate 100mm/rev, the average surface finish have improved by 94% over dry hard part machining. This corresponds to flank wear VB = 0.0644mm during heat assisted machining and 0.1425mm for dry hard part machining respectively. Such improvement was accompanied with longer tool life and secured surface integrity which improves the material’s life cycle.
Mold Issue in Details within the External Walled Structure
Authors: Sevcikova Hana , Rykalová Eva , Fabian Radek , Perina Zdenek , Halirova Marcela , Wolfova Marie
Published: April 2015

Article deals with the issue of mold in masonry structures. Attention was focused on the critical detail at expansion joint. Variants of solved detail are focused on the process of surface temperatures in the structure. This detail needs to be solved because of revitalization of the structure. Isotherms of the critical inner surface temperature and dew point temperature were used for the evaluation of the variants.
Wind Tunnel Experiments Focused on the Bridge Deck Stability Coefficients
Authors: Machacek Michael , Pospisil Stanislav , Krejsa Martin
Published: April 2015

An experimental study of an aeroelastic behavior of bridge deck under influence of the wind is carried out in a wind tunnel. Particular attention is paid to seldom analysed influence of the traffic upon the aeroelastic coefficients, known as flutter derivatives, characterising the dynamic response of a bridge deck. The results are compared to those of thin plate with high aspect ratio, which is proven to be aerodynamically stable.
Design and Analysis of Automobile Bonnet Using Natural Flax Composite Structure
Authors: Kong Chang Duk , Lee H.S. , Park G.L. , Park G.S. , Park Hyun Bum
Published: April 2015

In this work, a structural design on automobile bonnet using natural flax fiber composite is performed. The structural design results of flax/epoxy composite bonnet are compared with the design results of metal bonnet structure. Through the structural analyses using commercial FEM software, it is confirmed that the designed automobile bonnet using natural composite is acceptable for structural safety, deflection, structural stability and weight.
Indices for Fast Assessment of Bridge Condition in Taiwan
Authors: Yau Nie Jia , Liao Hsien Ke
Published: April 2015

Developed in 2000, the Taiwan Bridge Management System (TBMS) is an internet-based, nation-wide bridge management system used by all of the bridge management agencies in Taiwan. Currently, the TBMS has an inventory of more than 24,300 bridges with 14 years of visual inspection data and maintenance records. The inspection data of each bridge are input into the TBMS at least once per two years. In order to have a fast assessment of bridge condition in resisting natural disasters and traffic loads, five indices are established in this research: (1) Degree of flood resistance (DF), (2) Degree of mudflow resistance (DM), (3) Degree of earthquake resistance (DE), (4) Degree of loads resistance (DL), and (5) Degree of collapse resistance (DC). Calculation of these five indices is based on the inventory and visual inspection data of each bridge without further thorough site investigation. These indices are used for screening or sieving bridges out of the TBMS inventory that are potentially vulnerable to natural disasters or traffic loads, thus maintenance efforts can be put on such bridges to improve the efficiency of bridge management.
Changes in Floor Impact Sound Insulation Performance with Time
Authors: Kim Kyoung Woo , Yeon Jun Oh , Yang Kwan Seop
Published: April 2015

Floating floor structures installed with resilient materials are commonly used to reduce sound from floor impacts. Resilient materials minimize the transmission of vibrations by absorbing shock vibrations occurring on the upper part. The floor impact sound reduction performance of resilient materials is related to the dynamic stiffness, which is a physical characteristic of materials. However, the dynamic stiffness varies according to the increase in the loading time of the load that is installed on the upper part of resilient materials. The dynamic stiffness values increase with an increase in the loading time; an increased dynamic stiffness value decreases the vibration reduction effect. The present study focuses on a floor structure installed with resilient materials, and identifies the degree of reduction in floor impact sound insulation performance with the elapse of time. The insulation of sound from lightweight impact sound decreased with the elapse of time, whereas the heavyweight impact sound did not show significant changes.
The Development of Concrete Life Cycle Assessment System
Authors: Bok Young Jin , Tae Sung Ho , Kim Taeh Young , Yang Keun Hyeok
Published: April 2015

In the present study, a concrete life-cycle assessment system (CLAS) is developed that can easily and quantitatively assess green-house gas emissions during the production of concrete by applying life-cycle assessment techniques. The CLAS is divided into simple and detailed assessment methods; a database (DB) of a standard mix design and energy consumption amount, and basic green-house units applicable to each method, was constructed. A case assessment using the developed system showed that the green-house gas emission determined by the detailed assessment method differed from that by the simple assessment method by approximately 10%. These results show that the proposed method is suitable for estimating green-house gas emissions related to concrete.
Analysis of Floor Impact Sound Propagation around the Adjacent Houses
Authors: Kim Kyoung Woo , Chung Jin Yun , Yeon Jun Oh , Kim Myung Jun
Published: April 2015

The floor impact sound is a structure-borne sound that is propagated not only to the apartment directly below but also to various other locations. This study identifies how much floor impact sound, which is perceived as a problem for the whole apartment building rather than a problem for just the upper and lower floors, is propagated to surrounding apartments. Further, this study derives various variables for the cause of noise occurring in the apartment building. The measurement results indicate that most of the energy (38–54%) is propagated to the lower floor, which is an apartment directly underneath, for the noise produced when the floor slab is excited. Furthermore, it is found that the noise is propagated simultaneously to the apartments on the upper floor, as well as to the left and right sides.
The Composite Reinforcement of LLC «SK»
Authors: Kiski Svetlana , Teplova Zhanna , Sokolov Alexey
Published: April 2015

The review of the main physical and mechanical characteristics of steel and nonmetallic composite reinforcements is presented in the article. Also there are complex studying, analysis and synthesis of available information. Much attention is paid to recommendations for designing building constructions of different functions with nonmetallic composite reinforcements. Scopes of nonmetallic composite reinforcements in the construction industry in Russia and abroad are considered.Information about main producer and the official distributor of composite reinforcements is provided in the article. This company is the official distributor in the Northwest of the Russian Federation. Their production is successfully used on many objects under construction in Russia. Materials of the article are based on the real photographic materials provided by personal archive of the company.
Shear at the Interface between Composite Parts of Prestressed Concrete Section
Authors: Navrátil Jaroslav , Zvolánek Lukáš
Published: April 2015

Composite concrete beams made of prefabricated prestressed or non-prestressed element and cast-in-place reinforced concrete slab became very popular in present-day civil engineering practice. Two concrete composite parts of beam are cast at different times. Different moduli of elasticity, consecutive load application, and differential creep and shrinkage cause unequal strains and stresses in two adjacent fibers of construction joint. The requirement is to ensure that both parts act fully compositely, because the bending and shear designs of composite members are based on this assumption. Therefore the level of shear stresses at the interface between two parts must be limited. The objective of the paper is to review the methods for the calculation of shear stresses in construction joint, and to evaluate the influence of different age of two concrete composite parts on the level of shear stresses. Calculation method alternative to Eurocode 2 method is proposed and tested. It is recommended to calculate the shear stress from difference of normal forces acting on sectional components in two neighboring sections of the element. It was observed that differential shrinkage of concrete components can significantly affect the stress distribution. Numerical studies were performed based on real-life examples of composite beams.
Study on Finite Element Model for Impact Damage of Composite Structure
Authors: Park Hyun Bum
Published: April 2015

In this work, study on impact damage FEM model of composite sandwich structure was performed. Sandwich structure configuration is made of carbon-epoxy face sheets and foam cores. From the finite element method analysis results of sandwich composite structure, it was confirmed that the results of analysis was reasonable. The velocity of impactor to initiate damage was estimated, and in order to investigate the damage at the predicted velocity, impact analysis using finite element method was performed. According to the impact analysis results of sandwich structure, it was confirmed that the damage was generated at the estimated impact velocity. Finally, the comparison of the numerical results with those measured by the experiment showed good agreement.