bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Geometric Parameters on Mass Transfer Characteristics for Pulsatile Flow in Wavy-Walled Tubes
Authors: Bian Yong Ning , Li Chong Lin
Published: June 2014

In the experiment, three kinds of wavy-walled tubes with different wave factor Fw were applied to study the effect of geometric parameters on mass transfer characteristics. Results show that mass transfer characteristics are influenced significantly by the oscillatory frequency and the wavelength of the wavy-walled tube. The peak value of the mass transfer enhancement is obtained at the multiple order oscillatory frequency, and the effective mass transfer enhancement is occurred when the wave factor Fw = 0.58. For the same Re number, the mass transfer enhancement factor E increases with the oscillatory fraction P, and the optimal Strouhal number St corresponding to different peak E almost does not change with P.
Performance of Transient Temperature in Hot Spot Ignition
Authors: Gao Qun
Published: June 2014

This work presents a method to estimate probability initiating combustion and detonation by temperature load in void in energetic material. When a void is compressed its volume decreases and the temperature in the void increases. The local thermal source due to the void deformation in energetic material forms a temperature load which may initiate combustion and detonation. The temperature-time history in the void was called temperature load in this work. Its peak value and holding time are the necessary and sufficient condition initiating combustion or detonation of energetic material surrounding the void. Comparing with the energy acted on the unit area of hot spot, the performance of transient temperature which can better serve to reflect the physical essence in ignition. The main object of this work is to study transmitting process of temperature load from void to energetic material and probability initiating combustion and detonation by temperature load in void.
On the Influence of the Speed-Feed Interaction on the Wear Rate and Life of Multiple Coated Carbide Inserts Considering Rough Turning Process
Authors: Alajmi M.S. , Oraby S.E.
Published: June 2014

The impact of the cutting parameters; speed, feed, and depth of cut on the wear and the life of the cutting edge has long been a matter of debate among researchers. The cutting speed has long been agreed to have a prime influence in such a way that increasing speed leads to higher wear rate. Depth of cut has been concluded by majority of studies to have insignificant or negligible impact on edge wear and deformation. Despite its long established influence on the roughness of the machined surface, the effect of cutting feed on edge wear and deformation still requires more explanation. Cutting feed is a crucial parameter governing the product surface finish and dimensional accuracy and, therefore, its attitude during machining should be fully understood. This study presents experimental and modeling approach to detect the feed-wear functional interrelation considering various domains of the cutting speed. Results showed that the impact of the cutting feed is firmly associated with the level of cutting speed employed. Speed-feed interaction proved to be responsible for the performance of the cutting edge during machining.
Optimization of Milling Process for Aluminum Alloy Frame Part Based on Milling Force Analysis
Authors: Hao Yi Shu , Tang Guo Qing , Zhang Meng
Published: June 2014

In order to solve the problem of size guarantee related to thin-walled structure in traditional milling parameter selection, specific aluminum alloy frame part contains curved surface and thin-walled structure is studied. Numerical analysis is used in milling parameter selection method. Machining errors are calculated and checked based on milling force analysis. The milling process is simulated using finite element software. And aluminum alloy frame part processing is optimized from the angle of milling parameters according to the simulation results. Optimized milling parameters scheme is acquired, the results show that both machining precision and efficiency of the frame part are improved.
Characterization of Local Bolt (C= 0.071%) after Surface Hardened at a Temperature of 400 °C for 7 Hours with RF Plasma Nitrocarburizing Apparatus
Authors: Sudjadi Usman
Published: June 2014

Surface hardening on local bolt (C = 0.071%) with Radio Frequency (RF) - plasma nitrocarburizing apparatus has been carried out. Some local bolt component was cleaned with distilled water. The type of material of local bolt component was low carbon steel, carbon concentration 0.071%. After that the local bolt component was cleaned with acetone. The natural oxide layer on the surface of the local bolt material was etched with HF for 1 until 3 minutes. The local bolt component was cleaned again with distillation water. Then the local bolt component was sprayed with nitrogen gas. After that the local bolt component was hardened on the material surface with RF plasma nitrocarburizing at a temperature of 400 °C, for holding time 7 hours. Sample number 1 was sample before nitrocarburization. Sample number 2 was sample after nitrocarburization at a temperature of 400 °C, for 7 hours. Then the local bolt component was cut with mower as samples for microstructure observed. The samples were mounted, polished, and etched for microstructure observation with optical microscope. The surface hardness of the samples was tested with O.M.A.G micro-hardness Vickers, MHX 10, apparatus. The expenses tracking was 300 grf, and the times tracking was 15 seconds. The results show that the hardness of sample of bolt before nitrocarburization was 154.5 Kgf/mm2, after the sample was nitrocarburized at a temperature of 400 °C for 7 hours, the maximum hardness on the surface increased up to 205.6 Kgf/mm2. Matrixes on the base material were austenite, ferrite, and perlite.
Tensile Testing of Hybrid Composite Joints
Authors: Lamanna Giuseppe , Sepe Raffaele , Pozzi A.
Published: June 2014

In the present paper, results of experimental tests carried out on hybrid (bonded/bolted) and adhesive composite single-lap joints are showed. The laminate adherends were made by unidirectional carbon fiber/epoxy with symmetric stacking sequence. In particular, the tests were carried out to evaluate strength and failure mode of the different joints. These joints were subjected to quasi-static tensile displacement and tests were conducted using a universal testing machine. The maximum tension load that the specimen can bear is determined and the failure process is correlated to the lay-up of the composite and joint type.
Application of Bispectral Analysis in Vibration Fault Detection: A Review
Authors: Alfatih M.S. Somia , Leong M. Salman , Lim M.H.
Published: June 2014

Mechanical system degradation always leads to the unstable and nonlinear characteristics in the dynamic responses of the system to some extent. Conventional spectral methods based on Fourier transform have limited value in showing up fault information deviating from linearity. Higher order spectral analysis (HOSA) had been reported to be effective in providing information on nonlinear response. Bispectrum as one of higher order signal analysis tools found to be a useful tool in identifying nonlinear behavior of mechanical system due to vibration faults. This paper provides an introductory treatise of to Bispectrum, and reviews its applications in machinery vibration faults detection that includes misalignment, bearing and gear faults, and cracked shafts. The effectiveness and limitation of this technique are also reported for these faults based on published literature.
Response Surface Approach for Sensitivity Study of Neck Forces in Restrained Child Occupant during Side-Impact Crash
Authors: Shasthri S. , Kausalyah V. , Shah Q. , Abdullah Kassim A. , Idres Moumen , Wong S.V.
Published: June 2014

A study is undertaken to characterize the Neck Force (NF) of a CRS restrained 3 year old child occupant involved in lateral and oblique side impact. The Response Surface Method is used to map the parameter sensitivity upon the NF for impact speed of 32.2 km/h (20 mph) both individually as well as cross interactively. Design of Experiments is used with Latin Hypercube Sampling involving six predictors. A study of the response plots and statistical data obtained provide insights on the characteristic of each predictor with respect to the neck forces sustained. Greater parameter significance affecting neck forces is seen for narrow impact angles (φ ≤ 60°). Singularly, the impact angle parameter is revealed to be largely the most sensitive parameter to affect neck force especially at narrow angles. The critical range for this is identified to be between angles 50° and 70° while a secondary critical range is observed for angles below 34°.
Surface Morphology Study: Effect of Electrolyte pH on the Electrodeposited Sn-Ag-Cu (SAC) Solder Alloy
Authors: Yusof Sakinah Mohd , Jai Junaidah , Hashim Md Amin , Ismail Roslina , Hadi Abdul
Published: June 2014

pH control is significant in electrodeposition because they affect the characteristics of electrolyte and the deposit. This paper mainly analyses the processing conditions of electrolyte pH value on the electrodeposited SAC. Sn2+ ions will be obtained from the tin methane sulphonate acid while the Cu2+ and Ag+ ions will be obtained from their respective sulfate salts. Ammonium acetate helps in raising the pH of the bath. The FESEM analysis was carried out to examine the morphology of the electrodeposited nanocomposites. A variety of morphological patterns for the electrodeposits with different electrolyte pH is obtained. At low pH (2) electrolyte value, the electrodeposits show a very poor quality with rough surface. With increasing pH value (2.5), the averaged grain sizes decreased. The surfaces of the films electrodeposited at this pH value are generally quite smooth, uniform and compact. Later increment of pH values (3~4) has lead to the formation of porous and non-uniform electrodeposits. From the study, it is possible to observe that, even with the same composition, the deposits have different morphologies under different controlled parameter.
Application of Uniform Design and Kriging Interpolation in Optimization of ITI Dental Implant with Dynamic Chewing Loads
Authors: Cheng Yung Chang , Lin Deng Huei , Jiang Cho-Pei , Lee Cheng Kang
Published: June 2014

The aim of this paper is to present an integrated procedure for the optimization of dimensions of the ITI dental implant with dynamic chewing loads. The procedure is composed of uniform design of experiments, explicit dynamics finite element analysis, Kriging interpolation, and Nelder-Mead simplex local search optimization method. Firstly, uniform design method is employed to create a set of experiments. Then, explicit dynamics finite element analysis software ANSYS/LS-DYNA is used to analyze the micromotion of cortical and cancellous bones while the dynamic chewing loads acts on the implant. Next, Kriging interpolation is applied to construct the surrogate model of micromotion based on the input and output data of experiments. Finally, Nelder-Mead simplex local search method is applied to find the optimal solution of dimensions of dental implant under the goal of minimizing the micromotion. After performing the optimization procedure presented in this paper, the micromotion of the ITI dental implant system model can successfully be reduced by a rate of 29.7 %.
Study and Design of Checking and Testing Car for Whole Circuit
Authors: Ding Zai Ming , Liu Jin Feng
Published: June 2014

With the extensive application of electronic, computer and electromechanical integration technology in the automobile industry, the concept and mode of detecting and repairing to auto have a fundamental shift. So the corresponding professional teaching methods should be improved. In view of the present situation that automobile teaching equipment is not suitable for the new situation, we study and design the checking and testing car for whole circuit. The car based on a typical vehicle has a further development. And it has a new design, compact structure and convenient operating way, which also has the functions such as dynamic demonstrating all electrical appliances, circuit connection, fault setting, dynamic detection and ECU code query, reading out the fault code and data flow, waveform analysis and actuator testing by using computer diagnosis instrument. So it can help greatly to improve students’ technical skills and work ability.
Research on Project Site Sampling Method of Quality Supervision Sampling Inspection for Corrugated Sheet Steel Beams for Guardrail
Authors: Lu Yu Hong , Gong Bai Yan , He Jing Yi , Tan Gui Lin
Published: June 2014

By analyzing the component population and the requirements in the standards, we proposed sampling plan for project site. We can gain the lot acceptance by the minimum sample size.
Transport Parameters of Electrons in N2-O2 Streamer Discharge
Authors: Faraj Gulala Muhammad
Published: June 2014

Electron transport data been calculated numerically in mixture of molecular nitrogen and oxygen, using Monte Carlo simulation technique and a multi-term theory for solving the Boltzmann equation to investigate and obtaining the exact transport coefficients. It may serve the basis for modeling physical and chemical processes in streamer plasma discharges. Transport data influenced by the amount of O2in the mixture. The values of mean energy drift velocity reported.
Biofuels Produced from Hydrothermal Liquefaction of Rice Husk
Authors: Syamsul Hadi , Suyitno  , Kroda Kinastryan Jita , Arifin Zainal , Hery Kusbandriyo
Published: June 2014

This research is conducted for getting and examining bio-fuel from the process of hydrothermal liquefaction (HTL) using rice husk as raw material. The HTL process used ethanol as a solvent with concentration of 96%. Properties of the produced light fuels were examined on parameter such as water content, viscosity, calorific value, density, flash point, and gas chromatography-mass spectroscopy (GC-MS). The optimum yield 36.3 wt% of light fuel from HTL process of rice husk occurred at reactor temperature of 325°C and holding time of 45 minutes. Meanwhile, the optimum production of bio-fuel (light fuel + heavy fuel) was 69.3 wt% at reactor temperature of 325 °C and holding time of 30 minutes. The resulted light fuel has the calorivic value from 12.1 to 20.2 MJ/kg, viscosity from 1.11 to 1.6 cSt, and flash point from 14 to 29 °C. For the yield of bio-fuel from HTL process, the effect of reactor temperature was more pronounced than the effect of holding time. Further, the light fuels from HTL process with low water content are interesting objects as a fuel in internal combustion engines.
Faults Location of Cascaded Inverter Based on Artificial Intelligence
Authors: Liu Peng Kun , Jiang Wei , Ren Hui Jun
Published: June 2014

Cascaded H-bridges inverter has been gaining its ground in recent years because it can satisfy high voltage and power applications with medium volume semiconductors; however, it uses much more semiconductors than the traditional inverters which would increase the fault possibilities. Just because this case Cascaded H-bridges inverter is limited in many important industrial fields. In this paper, we, firstly, discussed the basic unit of Cascaded H-bridges inverter (namely, full-bridge inverter) and classify its inner faults, then we proposed a method to spot the faulty IGBT using neural network. We have also done lots of jobs on this fields which could be seen in the papers of our team.
A Small Concentrating Solar Power Tower System
Authors: Abu-Hamdeh Nidal H. , Alnefaie Khaled A.
Published: June 2014

A small scale prototype of functional R&D solar tower system (about 10 kW) to gather solar energy and store it in a molten salt tank will be designed, developed and built. The prototype tower system will be built at King Abdulaziz University in Jeddah, Saudi Arabia where direct irradiation is very high. Collectors of large mirrors (called heliostats) will be used to track the incident sunrays. The heliostats focus the energy flow towards solar receivers, where energy is transferred to a working thermal fluid. The proposed system consists of several heliostats directing incident solar rays to a tower of height about 20 meters. A solar receiver will be installed at the top of the tower to collect solar energy reflected from the heliostats. The heat transfer fluid (HTF) re-circulated in the receiver transfers the collected heat in the receiver to a storage tank. The storage tank contains molten salts.
The Potential Use of Tacca leontopetaloides as Green Material in Manufacturing Automotive Part
Authors: Mohd Makhtar Nurul Shuhada , Hamdan Noorhazila , Rodhi Miradatul Najwa Muhd , Musa Mohibah , Ku Hamid Ku Halim
Published: June 2014

The use of thermoplastic elastomers (TPE) in making parts of the vehicle such as a weather strip at the door and car window, floor mat, and dashboard is widespread. The commonly being used as in automotive parts manufacturing is styrene based TPE. Styrene based TPE released harmful gas, volatile organic compound (VOC) to the environment when it expose to the high temperature. Therefore, the new material with properties of thermoplastic elastomers is made from Natural rubber blend with localTacca leontopetaloidesstarch and silica extracted from rice husk (as filler). Investigation on the mechanical properties by using Universal Testing Machine (UTM) found that the green material produced has potential to replace the existing floor mat used in automotive production. Indeed, when the starch was plasticized by glycerol and the volume of Natural rubber was varies, the value of tensile strength of green material produced was higher compared with existing floor mat. The VOCs released when its expose to the high temperature was much lower than the existing floor mat used. On top of that,Tacca leontopetaloidesstarchhas potential to create low cost of new green materials in manufacturing of automotive parts.
Phase Change Material as Pump in an Organic Rankine Cycle
Authors: Hariharan Barghav Subramony , Suresh Kaushik
Published: June 2014

Organic Rankine Cycles (ORC) is predominantly used in waste heat recovery applications because of their low temperature working range. The main efficiency enhancement operation in an Organic Rankine Cycle is reducing the pump work .The pump converts electrical energy to flow energy. This input reduced and output maintained at the same level gives us a more efficient waste heat recovery system. The pump work can also be achieved by using a material that has the ability to expand on heating and revert back to its original state on cooling. The expansion property of the material is used to compress and drive the operating fluid through the cycle. Material that was observed to possess such properties was Phase Change Material. Conventionally PCM were used as thermal storage to preheat the working fluid in an ORC but a novel idea is to make the PCM utilize the heat rejected from the condenser and do the pump work. This paper discusses the various desirable properties of PCM to perform pump work efficiently and also the general layout and working of ORC system using PCM. The working fluid selected is toluene
Optimization Parameters and Synthesis of Fluorine Doped Tin Oxide for Dye-Sensitized Solar Cells
Authors: Suyitno  , Arifin Zainal , Ahmad Arif Santoso , Argatya Tara Setyaji , Ubaidillah
Published: June 2014

Transparent conductive oxide (TCO) is one of the important components in dye-sensitized solar cells. The main requirements of TCO for dye-sensitized solar cells are having a low electrical resistance and a high light transmittance. This study focuses on the synthesis of fluorine-doped tin oxide including its optimization. The synthesis of fluorine-doped tin oxide has been conducted under spray pyrolysis technique in which a precursor solution of SnCl2:F having concentration of 0.3, 0.5, 0.7, and 0.9 M. The spray pyrolysis was performed using a nebulizer with deposition time of 10 min. The glass substrate was heated at a temperature of 400, 450, and 500°C prior to deposition. The fluorine doped tin oxide was then measured the electrical resistivity for each area of ​​1 cm². Therefore, the mean and distribution of electrical resistivity of fluorine-doped tin oxide with an area of ​​10 x 10 cm then were predicted. In addition, the morphology and transmittance of fluorine-doped tin oxide are also examined. The optimization of the synthesis process of fluorine-doped tin oxide using spray pyrolysis was obtained at a concentration of 0.7 M with a sintering temperature of 400°C. The best fluorine-doped tin oxide has been also fabricated into the dye-sensitized solar cell and the performance has been studied.
The Effect of the Material of the Body of a Solar Still on its Performance
Authors: Srivastava Pankaj K. , Agrawal S.K. , Gupta K.M. , Pandey M.K.
Published: June 2014

An experimental study was conducted at Rewa, India (24°32′′N, 81°18′′E) in order to investigate the effect of the material of the body of a basin type solar still on its performance. Two single sloped basin type solar stills of G.I. sheet and F.R.P. respectively were constructed of equal basin area and size and were tested by keeping them side by side under identical conditions. Due to considerably lower thermal conductivity of F.R.P. as compared to that of G.I., around 30% higher productivity was observed in the former. The base heat loss as calculated with the help of the thermal model, in case of F.R.P. still was observed to be 36% which was much lower than 53% for G.I. still. The efficiency of the F.R.P. still was obtained as 32% whereas for G.I. still it was 26%.
The Numerical Analysis of the Thermo-Siphon Self-Injection Refrigeration System
Authors: Hu Ai Feng
Published: June 2014

The ejector performances were studied through simulation of solar thermosiphon injection refrigeration system. The influences of operating and structure parameters were analyzed on the eje-ctor performance. Some conclusions had been drawn: the optimum outlet and working pressure were 4241~5622Pa and 57803~70110Pa, the optimum ejector throat area ratio was 6.25, the ejector of 10 mm nozzle separation had maximum entrainment ratio and injecting flow. The influences of shock were analyzed on the ejector. The more shock number of nozzle exit, shock stagnation of the mixed chamber exit and the reflux of conical mixed chamber made the ejector performance decreased.
A Bank of Finite Memory Filters for Fault Detection and Adjusting Detection Latency
Authors: Kim Pyung Soo , Lee Eung Hyuk , Jang Mun Suck , Song Ki Sun
Published: June 2014

This paper proposes a new fault detection scheme using a bank of finite memory filters for discrete-time dynamic systems with multiple sensors. In the proposed scheme, fault detection is carried out by testing the consistency of two filtered estimates, which are obtained from the primary estimation filter and the auxiliary estimation filter using a bank of finite memory filters, respectively. Detection latency is considered as one of important performance criteria and focus on the improvement of detection latency even for high threshold value. Through extensive computer simulations for the F-404 engine system, it is shown that detection latency can be adjusted by the window length. Simulation results show that the trade-off between the fast detection performance and the noise-suppressing estimation performance should be needed for the proposed fault detection scheme in real applications.
Introduction of Fingerprint Recognition Method for Machinery Faults Diagnosis
Authors: Zakaria M. K. , Hee Lim Meng , Leong M. Salman , Hui K.H.
Published: June 2014

This paper presents a novel method to diagnose turbine blade faults by analysing wavelet result based on fingerprint recognition method. The study focuses on applying the fingerprint features extraction method to extract faults information from wavelet displays. Fingerprint recognition method studied in this paper is known as fingerprint bifurcations points. Experimental results show that this method could potentially be used as a features recognition method to identify the different types of machinery faults such as rubbing and rotor unbalance.
Process Sequencing Modeled as TSP with Precedence Constraints – A Genetic Algorithm Approach
Authors: Razali Noraini Mohd
Published: June 2014

This study addresses process sequencing subject to precedence constraints which arises as a sub-problem in scheduling, planning and routing problems. The process sequencing problem can be modeled as the travelling salesman problem with precedence constraints (TSPPC). In this study a new genetic algorithm (GA) procedure is developed which includes chromosome’s repairing strategy based topological sort to handle the precedence constraints and to generate only feasible solution during the evolutionary process. The procedure to select the task in sequence is based on “earliest position” techniques. This procedure is combined with roulette wheel selection, linear order crossover and inversion mutation. The effectiveness and the stability of the proposed GA are then evaluated against benchmark problems and the solutions are compared with the results obtained from research results published in the relevant literature. The developed GA procedure improved the performance of the algorithm with less number of generations and less convergence time in achieving optimal solutions. This result will greatly help to solve many real world sequencing problems especially in the field of assembly line design and management.
Research on Data Modeling for Management System of Alignment Information
Authors: Zhang Kai , Li Guo Xi , Gong Jing Zhong , Wu Bao Zhong , Zhang Meng , Yin Xin , Wan Fei
Published: June 2014

Due to lack of considering the non-geometric process parameters during assembly process planning, it is difficult to control the production cycle, cost, quality, reliability, stability and consistency of high-performance mechanical systems. To change this situation, a prototype software is developed by taking into account the non-geometric process parameters. Based on the alignment information, this paper concentrates on the data modeling of the system. With the system, the manufacturing process can achieve the assembly materials management, assembly process planning, alignment process monitoring, alignment data collection and statistical analysis. After analyzing the process data, design parameters will be refined and assembly performance will be optimized.
The Local Approximation Method for Structural Optimization
Authors: Nie Yi , Wang Yan , Sun Wei , He Yan , Hao Jing , Huang Tao
Published: June 2014

The local approximation method exhibits many advantage features and it is popular to a broad class of structural optimization problems. In this paper, both the mathematical modeling and case study of the local approximation method were studied. The theoretical analysis indicates that the primary optimization problem can be replaced with a sequence of explicit approximate problems by using the local approximation method. The explicit subproblems are convex and separable, which can be solved efficiently by using a dual method approach. The topology optimization of a guide rail design is then solved to testify the proposed method, which has been coded by Altair OptiStruct. The optimized design of a widely used guide rail with an “I” shape cross section is obtained and compared with the original design. The numerical results have shown that the local approximation method can effectively solve the structure optimization problems, especially the ones with hundreds of design variables or constraints.
Research of Information System Engineering
Authors: Lu Shan , Yang Yi Ping
Published: June 2014

Some traditional methods, such as NPV, now cannot afford appropriate decision assistance for information project. Information system project costs long time and need more complicated technologies, and it can be divided into phases. The real option of information project is playing an increasingly crucial role in the decision of investment. This paper considers the steps of information project, and the value project real option is descirte. Evaluate the real option of information project with improved binomial model which based on the characters of information project.
Measurement and Analysis Topological Characteristics of Video-Sharing Network
Authors: Ji Wen Li , Cao Xi Xi
Published: June 2014

Recently the fast-growing business of the Internet are Online Social networking services, Online Social networking sites also become the most popular sites. In order to establish future social network which is optimized, and to eventually exploit the user base for commercial purposes, in-depth understanding the social characteristic of these networks is important. In this paper, we present a large-scale measurement study and analysis on the social structure of YouKu. Our results validate the power-law, small-world and clustering coefficient properties, present the correlation and difference among four centrality properties. Finally we discuss the utilization of these structural properties for the commercial purposes.
Design and Analysis of Lean Production Planning and Control System for NPF Company
Authors: AL-Tahat Mohammad D.
Published: June 2014

Some of the important factors that are highly considered in NPF are; production processes, waste reeducation and optimization of raw materials. These concerns can be addressed through advance planning and scheduling and thoughtful programming for production, which reflects the goals, taking into account the different alternatives and the limited resources. On this basis the problem was formulated specifically, the problem specifically, taken into account the particular circumstances of NPF Company, special data was collected to configure a model for the planning and control of production processes. Implementation and analysis of all of that depended on brainstorming with the engineers of NPF, and then the marketing studies for finished productswere analyzed. We concluded after all to the study forecasts the future of the company products; based on the results an aggregate plan is designed. Then a production plans for all levels of planning and control of the proposed production quantities of all products are presented.
An Investigation for the Potential of Improving the Performance of Pattern Making Process in Steel Foundries: Case Study
Authors: Hayajneh Mohammad , AL-Tahat Mohammad D. , Alshobaki Salman , Khraisat Walid
Published: June 2014

This paper aims to examine the opportunities for possible improvement of the systems of pattern design and manufacturing, as well as the processes of casting design and technology in steel foundries. Solving these problems will improve the casting quality, and it will also standardize the work in one of the major bottlenecks in the production of steel casting. One big Jordanian foundry is selected as a case study. The foundry is referred to as GAZAL throughout this paper. A detailed flow process chart for the pattern making process with standardized times is developed, then possible improvements to the process are proposed. Several important milestones were developed and documented, among that; the development of a complexity classification and coding scheme of 6 levels to classify the products that GAZAL produced based on several criteria’s; the development of a mathematical model that relate the production time of the pattern with the complexity level. Finally conclusions are presented at the end of the paper.
Three-Dimensional Reconstruction of Three Real Roots Included Periodontal Ligament and Implant Study
Authors: Wang Qi , Chen Ling , Zhang Zhong , Niu Xing Hua
Published: June 2014

To investigate the periodontal ligament contains the real root of the three model cases, a combination of different implant and tooth variation of the stress distribution for the subsequent three root implant biomechanics analysis provides digital models. Methods: Mimics and Geomagic reverse engineering software for digital imaging method to obtain CT data processing. And the use of UG assembled in ANSYS workbench in finite element analysis. Results: A consistent with the real situation of three tooth root finite element model which contains periodontal ligament, and found that with the dental implant junction with the cross-sectional area decreases, where the stress amplitude fluctuations increases.
The Design of the Agricultural Equipment Integrated Device
Authors: Lin Yue Xiang , Wang Shu Peng , Du Hong Wei
Published: June 2014

This device is mainly designed for fertilization works for different kinds of fruit trees. It could simplify the traditional fertilizing methods, which are separately digging, fertilizing, and filling to one combined step. The simplified step is riding the device around the tree with three different operations easily done by one person. This advanced device is composed by rack, screwing handle, opener, wheel, filling devices and controlling sets. When operating, people just need to get the arc slot of the device rack stuck upon the root of the tree, then push screwing handle in order to ride the device around the tree. In this way, the digging, fertilizing combined with filling can be easily done together. By the help of controlling sets, we can change the amount, depth, height, and distance of the fertilization for different operators according to the size, growing condition and other condition of the tree. This device is capable saving efforts, labor and time, reducing the damage to the roots, fertilizing in a well-distributed way. Especially, it is suitable for hilly terrain and orchard where large-size machinery could not work.
The Head Injury Mitigation of an Adult and Child Pedestrian in a Frontal Vehicle Impact Using Response Surface Methodology
Authors: Venkatason Kausalyah , Sivaguru Shasthri , Abdullah Kassim A. , Idres Moumen M. , Shah Qasim H. , Wong S.V.
Published: June 2014

This work aims at achieving an optimized vehicle front-end profile for improved protection for both adult and child pedestrian groups. A seven parameter simplified vehicle front end model is used in which the Central Composite Design(CCD) is utilized to generate a Plan of Experiments for the adult and child pedestrian cases each. Head Injury Criteria (HIC) results from the simulations are tabulated as the response function f(y). The Response Surface method is used to obtain mathematical models for all cases for which optimization is carried out. A close correlation is obtained between the predicted response and the response observed via simulation for the optimized models. The optimized vehicle front-end profile for the adult pedestrian group is shown to be different than that of the optimized profile for the child pedestrian. Moreover, the study shows that both optimized profiles are not mutually applicable for safety. A simple weighted biasing method is used to obtain responses that minimize the response for both adult as well as child pedestrian groups mutually within a single profile. The final optimized model is shown to achieve a safe vehicle front-end profile which equally caters for both adult and child pedestrians.
A RSM Approximation in Probabilistic Nonlinear Analysis of Fire Resistance of Technology Support Structures
Authors: Králik Eng Juraj
Published: June 2014

This paper presents the methodology of the reliability analysis of the fire resistance of the steel structure of the cable way in NPP. The elastic and plastic solution of the steel structure under fire loads is discussed. The deterministic and probability analysis of the fire resistance of the steel structures are considered. The executed fire resistance analysis of the steel structures is investigated as the influence of temperature, permanent and variable loads. A Response Surface Method (RSM) for the nonlinear analysis of the fire structure reliability was used on program ANSYS. The advantages and disadvantages of the deterministic and probabilistic analysis of the fire safety are discussed.
Effect of Spontaneous Drying on Mechanical Parameters of Alkali-Activated Slag Mortar
Authors: Rovnaník Pavel , Topolář Libor , Schmid Pavel , Keršner Zbyněk
Published: June 2014

Alkali-activated slag is a material which has great potential for use in industrial applications. The main drawback of this material is the high level of autogenous and especially drying shrinkage that affects it, causing the deterioration of its mechanical properties. Mechanical and mechanical fracture parameter values show that an alkali-activated slag composite which is saturated with water is more brittle and exhibits lower strength in comparison with the same material after being surface-dried. These results are essential for the adjustment of testing conditions in order to obtain accurate and reproducible results.
Effect of the Extension of Basement Floor and the Importance of a Proper Design of Interaction between the Foundation and the Subsoil
Authors: Olekšáková Ivana , Ivánková Oľga
Published: June 2014

Proper design of structural system is the most important task for a structural engineer. Correct assessment of interaction of the building with the subsoil and its significant impact not only on the foundation structure but also on the entire building is very often forgotten. For design of all parts and for the whole structure the ultimate limit state (ULS) and serviceability limit state (SLS) are crucial. Static and dynamic analysis of the building has presently became an inevitable part of the design of difficult structure. In this paper both the changes, which are visible by the variations of the structural system, and the way of the foundation and necessity of knowing the properties of the foundation soil have been presented. Proper design of the interaction between the building and the subsoil is very difficult problem and therefore it is very important for experts to cooperate, mainly for structural engineer and geologist.
Fracture Mechanics Approach for Analysis of Delamination in Composite Plates
Authors: Žmindák Milan , Dekýš Vladimir , Novák Pavol
Published: June 2014

Delamination can be a substantial problem in designing composite structures. Modelling of delamination by finite element (FE) codes is limited. Previous efforts to model delamination and debonding failure modes using FE codes have typically relied on ad hoc failure criteria and quasi-static fracture data. Improvements to these modelling procedures can be made by using an approach based on fracture mechanics. A study of modelling delamination using the FE code ANSYS was conducted. This investigation demonstrates the modelling of composites through improved delamination modelling. Further developments to this approach may be improved.
Geometric and Static Analysis of the Historical Truss in Village Belá Dulice
Authors: Gocál Jozef , Krušinský Peter , Capková Eva , Kekeliak Miloš
Published: June 2014

Following a recently realized area structural-historical research on historical truss constructions in the regions of Liptov, Turiec, Orava and Kysuce, a project named Geometric analysis of historical truss constructions on the area of Slovak Republic has arisen. The first truss chosen for the analysis is the one of the Roman Catholic Church in Belá Dulice. This article presents its geometric analysis, as well as the results of the static analysis, focused on static behaviour of the roof superstructure. The attention is paid to the effect of slip in joints on the load redistribution in the structure as well as on the deformation of the main bearing members.
Influence of Fly Ash Type on Material Properties of Cement Paste
Authors: Padevět Pavel , Otcovská Tereza , Zobal Ondřej
Published: June 2014

Paper describes properties of cement paste included addition various kinds of the fly ash. Firstly is described the preparation of the cement paste. Next part is focused on the testing of the properties. Results of the testing are summarized in properties like a compression strength, Modulus of elasticity and tensile strength in bending. Finally the relation between material properties and volume weight is discussed. An article is described paste made from the same amount of cement and fly ash and water coefficient of 0.4.
Influence of the Age and Level of Concrete Fatigue on Prestressed Railway Sleeper Response: Parametric Study and Experiment
Authors: Šimonová Hana , Veselý Václav , Keršner Zbyněk , Culík Libor , Mosler Tomáš , Bilek Vlastimil
Published: June 2014

This paper presents a study on the influence of material parameters of concrete on the mechanical response of prestressed monoblock railway sleepers used on Czech railway tracks. The influence of selected mechanical/fracture parameters of concrete on the structural behaviour of the studied precast structural members is investigated by means of numerical modelling of standardized static loading tests, which are used as a tool for quality control during the manufacture of sleepers according to the European Standards for railway applications. The tests are numerically simulated using ATENA nonlinear finite element method software. The results of the simulations are compared with experimental data obtained via static loading tests performed on sleepers both before their use according to their designated purpose and after 17 years in operational service.
Numerical and Experimental Models of Load on Buldings from the Effects of the Atmospheric Wind
Authors: Michalcova Vladimira , Kuznetsov Sergej , Pospíšil Stanislav
Published: June 2014

The paper describes two different approaches of the solution of benchmark solution of bluff aerodynamic, which is the solution of wind pressures upon the cube exposed to the effects of air flow field. Two tasks are discussed in this article. One has the flow field with the constant wind velocity and low turbulence intensity, while the second one simulates the flow in the simulated Atmospheric Boundary Layer. Physical modelling is carried out at the wind tunnel of the Institute of Theoretical and Applied Mechanics in Telč. Numerical modelling is carried out at the Department of mechanics, Faculty of Civil Engineering, Technical University of Ostrava. Commercial code Ansys - Fluent has been used for the calculation.
Parameter Study of Asymptotic Sampling for Truss Structures Reliability
Authors: Hlobilová Adéla , Lepš Matěj
Published: June 2014

Sampling methods for predicting a reliability index such as Monte Carlo or Latin Hypercube Sampling are very time consuming thus advanced simulation techniques are frequently used. The asymptotic sampling is one of new techniques based on asymptotic results from reliability theory supported with a simple regression. Since the high sensitivity of the asymptotic sampling method to the control parameters has been reported, this contribution is focused on a study of the optimal parameter setting. The well-known truss structure is introduced and results with different parameter settings are presented.
Pilot Study of the Effect of Admixtures in Fine-Grained Cement-Based Composites on Volume Changes and Fracture Parameters
Authors: Bílek Jr. Vlastimil , Topolář Libor , Šimonová Hana , Kucharczyková Barbara , Havlíková Ivana , Pazdera Lubos , Keršner Zbyněk
Published: June 2014

The partial replacement of cement in concrete by an alternative admixture is a current topic in materials engineering. In order to examine the effect of replacing 20 % of the weight of Portland cement in fine-grained concrete using selected admixtures on volume changes and mechanical fracture parameter values, a set of specimens was fabricated from these quasi-brittle materials. Granulated blast-furnace slag, high-temperature fly ash, metakaolin and specially selected combinations of them were used as admixtures. Three-point bending fracture tests were conducted on these specimens and load versus crack mouth opening displacement (PCMOD) diagrams were recorded during the testing. In this paper, the outputs of the double-K fracture model were used for the prediction of beginning of stable crack propagation in fine-grained cement-based composites with admixtures.
Two Parameter Description of Crack Tip Stress Fields for Wedge Splitting Test Specimen: Influence of Wedge Angle
Authors: Seitl Stanislav , Bermejo Carlos , Sobek Jakub , Veselý Václav
Published: June 2014

Two parameter fracture mechanics uses for description of the crack tip stress fields, not only the stress intensity factor (SIF), but the second term of Williams expansion the T-stress. In the paper, the SIF and T-stress of typical wedge splitting specimens with usual loading arrangements varying in the wedge angle are directly computed using ANSYS finite element software. The influence of the wedge angle value is quantified.
Application of the Meshless Local Petrov-Galerkin Method for Subsoil Settlement Analysis
Authors: Mužík Juraj , Sitányiová Dana
Published: June 2014

The paper deals with use of the meshless method for soil stress-deformation analysis. There are many formulations of the meshless methods. The article presents the Meshless Local Petrov-Galerkin method (MLPG) local weak formulation of the equilibrium equations. The main difference between meshless methods and the conventional finite element method (FEM) is that meshless shape functions are constructed using randomly scattered set of points without any relation between points. The shape function construction is the crucial part of the meshless numerical analysis in the construction of shape functions. The article presents the radial point interpolation method (RPIM) for the shape functions construction.
Classification of Steel Mine Support Sections as per EC3 Classification
Authors: Janas Petr , Kološ Ivan , Fojtík Roman
Published: June 2014

The paper deals with classification of steel mine support sections according to Eurocode 3 section classification. Due to specific shapes of evaluated sections, the classification is based on experimental determination of rotation capacity.
Comparison of Fracture Energy Values Obtained from 3PB, WST and CT Test Configurations
Authors: Holušová Táňa , Seitl Stanislav , Canteli Alfonso Fernández
Published: June 2014

Modeling of concrete failure under fatigue loading is becoming a field of interest. Possible alternative testing solutions are now being searched. In this paper, the fracture energy for a certain concrete, resulting from three traditional fracture tests, namely three point bending test, wedge-splitting test and modified compact tension test, is investigated.
Isolation System Design and Noise Control of Roots Blower Room
Authors: Wang Zhong , Chen Chang Zheng , Kong Xiang Jun
Published: June 2014

With the actual case of isolation system design and noise control of roots blower room of a pharmaceutical factory in Shenyang taken into consideration, the overall computation was done on the basis of multi-vibration noise source. The vibration energy of equipments and noise propagation were analyzed both qualitatively and quantitatively with the spectral characteristics of vibration and wideband noise taken into account. Furthermore, the acoustic environment in the blower room was improved and the noise emission of the factory got down to the standard after the vibration isolation and noise reduction measures were applied. This work has important guiding significance and reference value for the projects on vibration isolation and noise control in the future.