bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of load carrying capacity and destruction mechanism of an intermediate anchorage steel plate for pillar jib crane
Authors: Gordziej-Zagórowska Małgorzata , Migda Wojciech
Published: October 2018

Pillar jib cranes are often mounted to existing floors with the use of an intermediate anchorage steel plate instead of using independent foundations. The process of designing such an intermediate plate for a pillar jib crane and a destruction pattern for plates of insufficient thickness are presented in this article. The required steps of the designing process are introduced and also the required level of detail for the numerical analysis. The aim of this paper is to provide a secure and safe approach to the design of such intermediate anchorage plates.
Investigation of natural frequencies of axially loaded thin-walled columns
Authors: Żmuda-Trzebiatowski Łukasz
Published: October 2018

The paper deals with correlation between natural frequencies of two steel thin-walled columns and the corresponding applied load. The structures are made of cold-formed lipped channel sections. The columns lengths were assumed to follow two buckling patterns – global flexural and flexural-torsional buckling. In the thicker structure two material models were considered – linearly-elastic and elastic-perfectly plastic. Numerical computations cover dynamic eigenvalue problem, linear buckling and geometrically (and materially) non-linear analysis. The correlation between squares of natural frequencies and the applied load is linear in both columns. The first natural frequencies drop to zero due to structural buckling. This method, called the Vibration Correlation Technique, allows to predict buckling loads on the basis of measured vibration frequencies of the structures. Plasticity does not affect the corresponding curves – the use of the presented technique is limited to the structures exhibiting elastic buckling behaviour.
Dynamic analysis of temporary steel grandstand equipped with different types of bracing system
Authors: Lasowicz Natalia , Falborski Tomasz
Published: October 2018

In the paper, behaviour of a temporary steel grandstand equipped with two different types of bracing system has been analysed through the numerical study. A typical solution concerning application of a diagonal tubular members has been compared with elements proposed by authors and called polymer dampers. A polymer element consists of two L-shape steel members bonded with polymer mass. The aim of the paper is to verify the effectiveness of polymer dampers in reduction of vibrations of temporary metal grandstands subjected to dynamic loads induced by spectators. The results of the study show that the response of structure equipped with two analysed bracing systems is different variable. The application of the polymer dampers results in substantial reduction in structural vibrations. Moreover, the decrease in values of accelerations of the grandstand with polymer dampers allows to maintain comfort of spectators at an acceptable level.
Soil-structure interaction effects on modal parameters of office buildings with different number of stories
Authors: Lasowicz Natalia , Falborski Tomasz
Published: October 2018

The paper summarizes the results of a numerical investigation designed to study the soil-structure interaction effects on modal parameters of three office buildings. The reinforced-concrete 4-storey, 8-storey, and 12-storey office buildings, each with additional two levels of embedded basements, represent low, medium, and high-rise structures, respectively. In order to conduct this research, detailed finite-element structure models were prepared. Soil-foundation flexibility was represented with the use of spring-based solutions, incorporating foundation springs and dashpots. The influence of diverse soil conditions (represented by their average effective profile velocities and shear moduli) on the dynamic characteristics of the analyzed three office buildings (e.g. fundamental vibration periods) was investigated and discussed.
Simplified method of applying loads to flat slab floor structural model
Authors: Tomasz Solarczyk Maciej , Ambroziak Andrzej
Published: October 2018

The article analyses the impact of the live load position on the surface of a reinforced concrete flat slab floor of 32.0 m × 28.8 m. Four variants of a live load position are investigated: located on the entire concrete slab, set in a chessboard pattern, applied by bands and imposed separately in each of the slab panels. Conclusions are drawn upon differences in bending moments, the time of calculation and the size of output files. The problems in the interpretation of results are presented too. A procedure is presented to model the reinforced concrete structures in computational programs. The recommendations of the Eurocodes are presented regarding to load combinations in the Ultimate Limit State (ULS). Convergence analysis of the finite element mesh is carried out to verify the obtained results. The law status on the implementation of the Building Information Modelling (BIM) technology in Poland points out significant time savings in the application of this technology.
Comparison of calculation models’ estimates with actual measured autogenous shrinkage in High-Performance Cement Composites
Authors: Zieliński Adam , Federowicz Karol , Kaszyńska Maria
Published: October 2018

There are several calculation models for estimation of shrinkage in concrete. The most popular ones are: ACI-209R-92 method, Bažant-Baweja model (B3), Gardner’a-Lockman’a model (GL 2000), CEB-FIP (CEB MC90-99), Spanish model (EHE), EuroCode method (EC-2) from 2004 and Tazawa–Miyazawa model (JSCE). Majority of aforementioned models do not include the deformation caused by the autogenous shrinkage. The methods assume the total deformation as a result of drying shrinkage action. Additionally, a non-standard method was proposed by Jonasson and Hedlund. However it only is used to determine the autogenous shrinkage of High-Performance Concretes (HPC). Tazawa-Miyazawa model and Jonasson-Hedlund method are based on the proportions and material properties such as water/cement ratio, water/binder ratio, type of the cement, or start of setting time. In contrary, the CEB MC90-99 and EC-2 models correlate the autogenous shrinkage with the overall compressive strength of concrete. The article presents the analysis of various calculation models in comparison to actual measurements. The autogenous shrinkage was measured in four cement composites starting at casting up till 28 days of curing.
Use of DMDA method for production of heavyweight concrete
Authors: Techman Mateusz , Skibicki Szymon
Published: October 2018

Waste materials are defined as all unwanted substances from manufacturing processes, including mining, industry, agriculture and others. One of the most commonly used waste product in concrete manufacturing is Fly Ash (FA). Studies have shown that the content of Fly Ash increases the workability of concrete, being useful in production of Self-Consolidating Concretes (SCC). One of the designing methods involving high amounts of fly ash is based on the Densified Mixture Design Algorithm (DMDA). This article attempts to work out HWSCC manufacturing method using the DMDA method with the use of barite and magnetite aggregates. The study integrates six concrete mixes. Concrete strength was tested on 10x10x10 cm samples after 3,7 and 28 days. The rheological properties were tested with Slump Test to find out if the mixes exhibit self-consolidating properties. Concretes with magnetite aggregate exhibit higher strength than concretes with barite aggregate. The study has shown that the DMDA method, designed to produce durable, low-cement concrete may not be applicable in the case of crushed aggregates. The study has shown that the method allows to decrease the cement amount and re-place it with pozzolan waste product to acquire concretes with similar properties to the ones acquired using different methods.
Use of radiography images and gray level co-occurrence matrix to investigate gravitational granular flow
Authors: Waktola Selam , Grudzień Krzysztof , Niedostatkiewicz Maciej , Babout Laurent
Published: October 2018

The paper presents analysis of granular gravitational flow based on radiography images processing. The investigations were conducted for silo model geometry with concentric/eccentric discharging modes. The continuous X-ray radiography scans of granular material distribution, acquired during flow, were obtained by means of an especially designed model silo with rectangular bin and different settings of hopper angles. Image processing involved texture analysis methods, the Gray-Level Co-Occurrence Matrix (GLCM). The texture analysis of radiography images provides information about changes of granular porosity in different silo zones during silo discharging process. This technique allows to divide the silo space into a number homogenous regions with similar porosity level. The proposed methodology was applied to analyse the flow in silo model with various hopper angles.
Multi-criteria analysis of the construction technologies in the aspect of sustainable development
Authors: Gicala Magdalena , Sobotka Anna
Published: October 2018

The complexity of sustainability complicates the design work and requires the implementation of Integrated Life Cycle Design. Due to the need of balance between environmental, social and economic aspects and the multitude of analysis indicators, the assessment of existing buildings is a multi-criteria problem too. The aim of the study is to compare three construction technologies – two traditional solutions and an innovative technology – in the aspect of sustainable development. The assessment was limited to the building envelope materials and included in entirety of 13 environmental, social and economic indicators, characteristic for the first stage of building life cycle. The absence of explicit dominance of one technology over another in terms of these factors was a starting point for the multi-criteria analysis. Based on the comparison of given technologies by WSM and TOPSIS methods, the multi-criteria analysis was carried out and the most advantageous technology was indicated. The results allow for an indirect selection of building materials to fulfil the sustainability requirements for the building.
Multicriteria assessment of selected types of the single-layer exterior walls
Authors: Plebankiewicz Piotr , Leśniak Agnieszka
Published: October 2018

The choice of technology for the construction of external walls and materials is made at the building design stage. This is one of the key decisions, any change after the beginning of construction is bound to cause serious consequences. It is therefore worth analysing various design solutions beforehand, taking into account the cost, quality, execution time, as well as the partition parameters obtained. The paper presents three variants of the solution for single-layer external walls that can be used in single-family buildings. Costs were calculated and selected technical parameters were listed. The evaluation of the proposed variants was made using the multi-criteria analysis method.
Transparent façades – selection of construction materials with the use of modified multi-criteria spider’s network analysis method
Authors: Zapała Oliwier , Wieczorek Damian
Published: October 2018

the main and most impressive elevations of the building. It also focuses on some issues related to high requirements placed on façade systems in terms of insulation from environmental conditions and comfort of the future users of the building. Due to the fact that there are many materials that can be used for the main structural elements (columns, spandrel beams and ribs) of load-bearing façade structures, the authors of the article attempted to do a multi-criteria comparative analysis of three different materials (safety glass, glulam and rolled steel) of a 6-meter-long reference column. The set of criteria, consisting of twelve elements, was adopted for comparative analysis. A combination of two methods was selected for performing the multi-criteria analysis: a geometric method of spider’s network and a mathematical method of the adjusted index of summation.
Multicriteria assessment of selected types of ceilings
Authors: Nowak Julia , Plebankiewicz Edyta
Published: October 2018

The paper compares three systems of the rib-and-slab ceiling: Vector, Rector and Teriva. The following comparison criteria were selected: the tare weight of ceiling beams, execution time, slab faulting, sound insulation, thermal insulation and aesthetics of the lower surface. The results of the multicriteria comparative analysis clearly indicated the advantage of the Vector ceiling, assuming the same weights for all criteria taken into account.
The influence of selected static and dynamic parameters of resilient mats on vibration reduction of railway tracks
Authors: Kraśkiewicz Cezary , Zbiciak Artur , Oleksiewicz Wojciech , Piotrowski Andrzej
Published: October 2018

The paper presents laboratory methods of testing the prototype resilient mats, used in rail track systems in order to reduce vibrations transmitted to the vicinity of the railroad and to improve the resistance of the railroad structure. The laboratory testing program was carried out for elastomeric materials (polyurethane based). The key parameters being investigated in the Warsaw University of Technology laboratory unit were used in order to determine the insertion loss vibration level by applying analytical method. The paper presents the influence of selected parameters i.e. static and dynamic moduli on the reduction of vibration and structure-borne sound level – i.e. the value of insertion loss parameters.
Hardening Curve Plotting and Determination of the Coating Limiting State Criterion based on the Continuous Indentation Method and Computational Modelling
Authors: Ivanchenko Alexander , Zhdanov Alexey , Morozov Valentin
Published: October 2018

The article describes the method of determining the parameters of the hardening curve of homogeneous and structured coatings (modulus of elasticity, tangential modulus of elasticity and yield strength) required for the strength analysis of parts with coatings that determine their basic performance and strength characteristics. The dependence for determination of tangential (tangential) modulus of elasticity using the results of nanoindentation is proposed. An algorithm for determining the yield strength of the coating material is developed based on solving the problem of elastic-plastic deformation of the coating during the introduction of the indenter by the finite element method. According to the proposed method, the parameters of the TiN/AlN in coating hardening curve were determined based on the results of indentation of the sample of tool high-speed steel with the appropriate coating.
A Method of Calculating Principal Stress Trajectories in Powder and Porous Materials Obeying a Piece-wise Linear Yield Criterion
Authors: Alexandrov Sergei , Lyamina Elena , Date Prashant
Published: October 2018

The present paper deals with the system of equations comprising the pyramid yield criterion together with the stress equilibrium equations under plane strain conditions. The stress equilibrium equations are written relative to a coordinate system in which the coordinate curves coincide with the trajectories of the principal stress directions. The general solution of the system is found giving a relation connecting the two scale factors for the coordinate curves. This relation is used for developing a method for finding the mapping between the principal lines and Cartesian coordinates with the use of a solution of a hyperbolic system of equations. In particular, the mapping between the principal lines and Cartesian coordinates is given in parametric form with the characteristic coordinates as parameters.
Bioconvection of Nanofluid Past Stretching Sheet in a Porous Medium in Presence of Gyrotactic Microorganisms with Newtonian Heating
Authors: Pourrajab Rashid , Noghrehabadi Aminreza
Published: October 2018

In this study, the effect of Newtonian heating on the boundary layer flow and heat transfer over a stretching surface in a porous medium in the presence of gyrotactic microorganisms and nanoparticle fractions are analysed. The governing equations are reduced to a system of couple non-linear ordinary differential equations, subjected to the Boussinesq approximation and asymmetric heat conditions. The reduced governing ordinary differential equations are then solved numerically. The solutions obtained are graphically represented. The effects of the controlling parameters on the flow, heat, nanoparticle concentration and the density of motile microorganisms have been examined. The results of the present study show the flow velocity, heat and mass transfer and motile microorganism characteristics on the stretching sheet are strongly influenced by the bioconvection parameters and Newtonian.
A Condition for Complete Flattening of Asperities in a Rough Contact
Authors: Murashov Mikhail V.
Published: October 2018

Considering rough surface profiles in a contact model is of decisive importance. In the up-to-date rough contact models there remained underexplored the opportunity of complete flattening of smaller asperities and therefore the need of using the multilevel roughness models, including fractal ones. If higher level asperities are not flattened completely when pressed, then they will be able to impact on the contact process. This paper considers model problems of elastic-plastic contact with hardening for a body with protrusions and two pyramids as the objects similar to asperities. Modeling results show that asperities are completely flattened only on condition of confined compression. For real contacting rough surfaces under low pressures, complete flattening of asperities will not occur. It is shown that roughness elements on the surface of the asperities do not disappear even at severe deformation of the latter. The reason is a combination of the asperity form and hardening of material, while the consequence is a reduction of the real contact area.
A Route Reservation Approach for an Autonomous Vehicles Routing Problem
Authors: Agafonov Anton , Borodinov Aleksandr
Published: October 2018

Autonomous vehicle development is one of many trends that will affect future transport demands and planning needs. Autonomous vehicles management in the context of an intelligent transportation system could significantly reduce the traffic congestion level and decrease the overall travel time in a network. In this work, we investigate a route reservation architecture to manage road traffic within an urban area. The routing architecture decomposes road segments into time and spatial slots and for every vehicle, it makes the reservation of the appropriate slots on the road segments in the selected route. This approach allows to predict the traffic in the network and to find the shortest path more precisely. We propose to use a rerouting procedure to improve the quality of the routing approach. Experimental study of the routing architecture is conducted using microscopic traffic simulation in SUMO package.
Research on Reliability Modeling, Allocation and Prediction of Chemical Production System
Authors: Miao Yongchun , Kang Rongxue , Chen Xuefeng
Published: October 2018

Reliability allocation and prediction play an important role in the chemical production system, controlling the significance of each production allocation and predicting system reliability to analyze the designs in each system or integrated system if meeting requirements or not. This paper takes an ethylene plant as an example to study reliability modeling, allocation and prediction of related system. It is aimed to allocate and predict each production system or unit. In terms of system reliability allocation, it finds out the reliability allocation R in integrated system is 0.76460 with improved fuzzy analytic hierarchy process (AHP). Due to the number higher than initial reliability value of 0.73886, it illustrates the integrated reliability allocation meets the design requirements. In terms of reliability prediction, the result is more accurate when using Bayes fuzzy reliability prediction to calculate system reliability level and it can reflect this kind of indeterminate small sample data better.
Distinctive Features of Altitude-velocity Characteristics of Detonation Gas Turbine Engines
Authors: Tkachenko Andrey , Rybakov Viktor , Filinov Evgeny
Published: October 2018

The paper describes the distinctive features of the altitude-velocity characteristics of detonation gas turbine engines. The necessity of developing a new type of gas turbine engines is substantiated and the main features of detonation engines are described. The principal constructive scheme of detonation gas turbine engines is presented. Developed the one-dimensional mathematical model of detonation gas turbine engine. This model describes a working process in a gas generator and a traction module. Its verification with a real prototype is performed. A number of studies were carried out using the developed mathematical model. A comparison of the pulsating engine with the classic afterburner was performed. From the obtained results it is concluded that detonation engines are more economical than the engines of traditional schemes. It was also revealed that it is possible to obtain a range of flight speeds depending on a certain height only by adjusting the gas generator according to different control laws. In this regard, the purpose of further work will be the development of a three-dimensional mathematical model of the detonation engine and the creation on its basis of a stand of virtual tests for further research.
Increase the Efficiency of a Gas Turbine Unit for Gas Turbine Locomotives by Means of Steam Injection into the Flow Section
Authors: Filinov Evgeny , Tkachenko Andrey , Omar Hewa Hussein , Rybakov Viktor
Published: October 2018

In the modern world of railways, electrification is given great importance. Currently, more than 50% of all freight traffic carried out by electric traction. However, today, about half of the railways are not electrified, so it is necessary to use thermal engines to drive the locomotive. One of the possible variant is use gas turbine unit. The power of the gas turbine unit is given to the electric generator, and the electric motors drive the locomotive. In the present paper, as a power plant of a gas turbine locomotive, considered gas turbine unit with a twin -shaft gas generator of two schemes: 1- with steam supply to the inlet of the high-pressure turbine (into the combustion chamber) and 2- with steam supply to inlet of the free turbine. By CAE system of ASTRA, Collaboration operation lines calculated for different variants of steam injection. When the steam injected into the inlet of a free turbine and a high-pressure turbine. in the case of steam supply to the input of the free turbine and the high-pressure turbine there is a significant shift in Collaboration operation lines, which can lead to a decrease in the gas-dynamical stability of the compressors, and efficiency. To maintain the position of Collaboration operation lines, was applied the correction of the throughput capacity of free turbine nozzle vanes (by 15%). In the case of steam supply to the inlet of a free turbine, to ensure gas-dynamic stability of the compressors, a change in the throughput capacity of its nozzle vanes is required.
An investigation of Outlier Detection Procedures for CMM Measurement Data
Authors: Chelishchev Petr , Popov Aleksandr , Sørby Knut
Published: October 2018

The paper analyses methods for outlier detection in dimensional measurement. The cross sections of an internal cylinder were inspected by CMM (coordinate measuring machine), and received data sets were employed for further investigation. The efficiency of Rosner’s and Grubbs’ methods for excluding outliers from the measuring data had been estimated. The method of Rosner had been defined as the most effective for this case study. The simulation results were confirmed by experimental verification.
Integrated Smart Plug Design
Authors: Nasution Tigor Hamonangan , Hanafi Muhammad , Tanjung Kasmir , Fahmi Kasmir
Published: October 2018

Smart plug technology currently for user providing one plug module that is able to monitor and control the state of electrical appliance. The addition of plug number gives some deficiencies such as from cost point of view. By looking at the disadvantage made the tool which is able to monitor and control electrical appliance so that smart plug more than one integrated plug module. The manufacture of plug modules includes system design, sensor type selection in module, data delivery process, comparison of measurement module with measuring instrument and system test. From the results of the design is known that the module can perform data transmission, display the monitoring page and do the control and obtained percent accuracy of current readings obtained between 91.50% to 99.61% and the percent accuracy of the voltage readings obtained are ranged between 98.95% to 99.90%.
The Tricycle Mobile Robot Movement Simulation
Authors: Larkin Eugene V. , Antonov Maxim A. , Privalov Alexander N.
Published: October 2018

The analytical model of three wheels mobile robot as the control object is worked out with use of the theoretical mechanics. Model includes two parts, part which describes longitudinal acceleration and dynamics of maneuvers on the azimuth angle and part which describes transverse oscillations of trunk relatively to the ground. For description of acceleration characteristics and maneuvering on the azimuth angle robot is considered as the trunk with installed two direct current motors at the base of the isosceles triangle and absolutely passive wheel installed in the vertex of the isosceles triangle. For description of transverse oscillations robot is considered as rigid trunk placed on viscose-elastic supports, and every support moves on its own land trajectory. It is shown that the result obtained may be used both for direct synthesis of mobile robot control system, and for evaluation of Nyquist frequency of sensors signal digitizing, which minimize information losses in mobile robot digital control system.
Noise Reduction on the Tilt Sensor for the Humanoid Robot Balancing System Using Complementary Filter
Authors: Maulana Rizal , Kurniawan Wijaya , Fahmi Hafizhuddin Zul
Published: October 2018

The aim of the research is to present the design of a system which is capable for noise reduction on the reading of the tilt sensor data used in a balancing system on humanoid robots. Humanoid robot is a robot that has body construction like a human. Humanoid robots can make a movement by walking with both legs. In order to walk properly, humanoid robot needs to have a proper balancing system. The humanoid robot balancing system consists of tilt sensors, either an accelerometer or a gyroscope sensor, main processing unit and actuator in the form of servo motors on each robot’s joint. The tilt sensor is used to detect tilt angle of the robot body. When sensor gives information about the robot is in a position of tilt angle that will cause the robot to fall, the main processor will send commands to the actuators to do the balancing action so the robot will go to a balancing position. Unfortunately, the tilt angle reading value obtained from tilt sensor, still contain noise. That noise makes the reading of the tilt angle of the robot body to be inaccurate. Therefore, a filtering method is required to reduce the noise. In this research, complementary filter is used to overcome this problem. From the test result, the complementary filter is able to reduce noise on the tilt sensor data value reading. The optimum filtering result was obtained with the use of filter coefficient of 0.96 and sampling time of 50ms, where the average tilt angle error value is 0.775° on the x-axis and 0.691° on the y-axis. In another test, the robot is able to perform a balancing action based on the output of the complementary filter. So the robot was always able to maintain its position on balanced condition.
Robust Adaptive Nonlinear Dynamic Inversion Control for an Air-breathing Hypersonic Vehicle
Authors: Wu Guanghui , Meng Xiuyun , Wang Jie
Published: October 2018

This paper presents a robust adaptive nonlinear dynamic inversion control approach for the longitudinal dynamics of an air-breathing hypersonic vehicle. The proposed approach adopts a fast adaptation law using high-gain learning rate, while a low-pass filter is synthesized with the modified adaptive scheme to filter out the high-frequency content of the estimates. This modified high-gain adaptive scheme achieves a good transient process and a nice robust property with respect to parameter uncertainties, without exciting high-frequency oscillations. Based on input-output linearization, the nonlinear hypersonic dynamics are transformed into equivalent linear systems. Therefore, the pole placement technique is applied to design the baseline nonlinear dynamic inversion controller. Finally, the simulation results of the modified adaptive nonlinear dynamic inversion control law demonstrate the proposed control approach provides robust tracking of reference trajectories.
Improved model of Advanced Heavy Water Reactor(AHWR)for Control studies
Authors: Gokul Girish , Shimjith Sreyas Rajgopal , Bandyopadhyay Bijnan
Published: October 2018

This paper presents a modified version of coupled neutronics - thermal hydraulics model of Advanced Heavy Water Reactor (AHWR) for control studies. Earlier reported models assume, for the sake of simplicity, that the steam drum level and pressure are being strictly regulated at their respective set points, thereby neglecting these dynamics. However, such models are not suitable for analysis / controller design for the normal mode (load following mode) of operation of AHWR wherein the demand power setpoint is adjusted with respect to fluctuations in steam pressure. The work reported in this paper bridges this gap by including the steam drum pressure and level dynamics in the model. This leads to a model suitable for investigating control related aspects of all operational modes of the reactor. Efficacy of the proposed model is demonstrated through nonlinear simulations.
Optimization of Molding Parameters Using Taguchi Method to Increase the Electrical Conductivity and Tensile Strength of Conductive Polymer Composites
Authors: Suherman H , Pulungan P , Yovial Y , Irmayani
Published: October 2018

The focus of this research is to increase the electrical conductivity and tensile strength of conductive polymer composites (CPCs) materials using Taguchi method. The efforts made is by optimizing the molding parameters, using two different size of conductive fillers, ie G25 (25 μm) and G13 (13 μm) in producing CPCs material. The molding parameters used are molding time and molding temperature. S/N ratio is use to obtain the optimum molding parameters, ie the larger is better. The results showed that Taguchi method L9 (23) succeeded in increasing the electrical conductivity and tensile strength of G25/G74/epoxy and G13/G74/epoxy composites. The highest electrical conductivity and tensile strength is on G13/G74/epoxy composites, ie 3.51 S/cm and 155.50 N/mm2 respectively.
Empirical Modeling of Average Cutting Speed during WEDM of Gas Turbine Alloy
Authors: Singh Bhupinder , Misra Joy Prakash
Published: October 2018

Cutting speed (CS) is a key performance measure to achieve optimal utilization of the WEDM process. However, input process parameters of WEDM and combination of wire and workpiece material greatly hamper CS and hence productivity and machining efficiency. Therefore, it is essential to pick the right combination of parameters and wire and workpiece material to obtain better CS. In this paper, four process parameters: Ton, Toff, Sv, and Ip were chosen to develop an empirical model for CS during WEDM of nimonic 263 to provide a guideline to the potential users of the technique. This paper describes the response surface methodology (RSM) based mathematical modeling for average cutting speed. Furthermore, analysis of variance (ANOVA) was applied to find out significant process parameters and it was depicted that pulse on time and peak current were the major parameters affecting CS. In addition, WEDMed surfaces were analysed through FE-SEM at various discharge energy levels. The WEDMed surfaces appeared in the form of micro-cracks, craters, spherical droplets and the lump of debris. It is obvious from the current investigation that input parameters have the significant influence on cutting speed. The key features of experimental procedure are also highlighted in this paper.
Interaction between plastic deformation and hydrogen damage behavior of 30CrMnSiNi2A steel
Authors: Fu Lei , Fang Hongyuan
Published: October 2018

The interaction between plastic deformation and hydrogen damage behavior of 30CrMnSiNi2A steel was investigated by pre-strain tensile tests and hydrogen charging by electrochemical method. This paper mainly contains two parts. The plastic deformation was restrained by hydrogen-charged, and the effect of hydrogen brittleness damage behavior was accelerated by pre-plastic deformation measure. Tensile pre-strian tests with hydrogen charging at current density from 0 to 50 mA/cm2 for 120 min were performed at room temperature. Both rate of reduction in areaand elongation were decreased due to the transition from ductile to brittle fracture by hydrogen charging, which meant the ability of plastic deformation was reduced by hydrogen. With hydrogen concentration increasing, yield strength also increased indicating that the plastic deformation forming conditions of steel were improved by hydrogen. Hydrogen content increased with pre-strain measured by glycerol gas collection method. Due to the pre-strain measure before hydrogen charging, the reduction of area and elongation were further reduced, while the strength was unexpectedly low. It was because pre-strain promoted the formation of hydrogen-induced crackings (HIC). This proved that the plastic deformation promoted the generation of hydrogen damage.
Material Characterization of Test Contact Pin
Authors: Ramamoorthy Praveen kumar , Fischer Florian , Guan Han , Hudda Murad
Published: October 2018

Test Contact Pin is used for testing the functionality and quality of the micro-devices at extreme temperatures before shipping to customers. The contact pin transfers current & signal to the device tested through dynamic contacting where the material resistance of the pin and the contact resistance between the pin and the device plays a significant role in influencing the effectiveness of the test process. Available material specifications for these pins in the market are for ambient temperature only. The test contact pin was characterized across temperatures onto matte Sn leadframe for its contact resistance and force with respect to number of touchdowns. Contact resistance and pin force are the key variables used to understand the mechanism of the process which is also used for determining the lifespan of the contact pin. An automated and sophisticated contact tester tool (CTT) was used to characterize the test contact pin on the mattes Tin leadframe across temperatures (-43°C, 25°C and 150°C) and at fixed pin deflection. Based on the results, it was observed that the contact resistance was higher at higher temperatures. Further data analysis revealed that this phenomenon was due to influence of various factors such as temperature, leadframe material type and the material migration of Sn from leadframe to the test contact pin tip.
Combining Time and Physical Workload Analysis on Cold Press Working Group for Operator Management in Manufacturing Company
Authors: Suryoputro Muhammad Ragil , Ginanjar Tresna Candra , Sari Amarria Dila
Published: October 2018

Efficiency improvement in manufacturing company is essential to ensure the cycle of continuous improvement. Prior decision was reducing 6 operators in the cold press team work into 5 workers. Thus significant changes, of course, would resulted in the change of the workload experienced by each operator. The research objective in this study is validating from the productivity of the reduction conducted by measuring the workload with combining Full Time Equivalent (FTE) and Cardiovascular Load Percentage (%CVL). The result states that there are differences in measurement results workload from both methods. Based on the FTE method, all Cold Press operator’s workload has an index in average of 1.4128 with all was above 1.28 indicating the “Overload” condition. On the other hand, based on the physical workload method obtained that % CVL in average was 8.272% with all operator was below 30% which indicates the workload of all Cold Press operators were in a not experiencing fatigue category. Keywords: Workload, FTE, %CVL, productivity, Physical Workload.
A Study for New Balance Sports Products to Analyze and Design
Authors: Huang Yu-Che , Huang Tai-Shen
Published: October 2018

In recent years, under the influence of globalization, more and more different needs have created different sports products. In general, they are mainly used for cardio training and muscular endurance training, and their products for human balance training are few. Balance training has always been one of the most important exercises, but most exercise training is often overlooked. In this study, we searched for sports product patents and related literature that improve balance training and determined the direction of innovative design based on the different patent categories. Based on the results of the analysis, we have redesigned a model that can effectively provide innovative sports products with different angular misalignments and different displacements. In this research, we search, analyze and summarize the related patents and further identify the methods of innovative design to accomplish the required technologies for this design. The relevant design of this study is to use SolidWorks to draw 3D models for motion simulation and size checking. Then use the ANSYS11.0 command module to analyze the body structure of the force situation, to determine the strength and safety. Finally, make the original. Finally, this study hopes to provide a design reference for future sports product design engineers through this design process.
Derivation of Life Cycle Cost Model for Selecting Optimum Decisions in Engineering Asset Management
Authors: Cahyo W.N.
Published: October 2018

It is common that interdepartmental conflict may arise in an organisation to select which decision to be taken, especially in the area of engineering asset management. In this paper, an engineering asset management related case study is discussed and a derivation of a life cycle cost model is proposed to assist finding the optimum decision. Another challenge in this study is a situation that the data and information required to calculate the total cost is unavailable. To deal with this situation, a cost comparison approach is proposed as well as a sensitivity analysis in order to select the optimum decision if the uncontrolled variable in the system nature changes. The result shows that the total cost model derived from the life cycle cost model is capable to assist selecting the optimum decision. A simple spreadsheet based Monte Carlo model is also developed to represent the randomness of the time to failure during the five years of time horizon of the analysis.
Automated programming robot component transfer system utilizing machine vision as detection interface
Authors: Vermaak H J , Rogers L
Published: October 2018

Modern day automation systems rely on fixed programming routines to carry out their operations. If an automated flexible system is introduced onto such a production line, the complete reprogramming process required for new products needs could be automated with limited loss in production time. Therefore, instead of reprogramming each new position for the robot system the system takes over real-time control of the robot and carries out the required steps autonomously. The benefit with such a system would be that the robot would not need to be reprogrammed for every new routines but is controlled in a real-time environment to carry out new procedures based on external vision sensors. Using a real-time system could remove the need for a fixed programming environment and replace it with an automated changing programming setup. This could result in a system automatically adapting to a new product introduction through real-time machine vision processing techniques.
A novel geometric error identification methodology for the tilting head of five-axis machine tools based on double ball bar
Authors: Fan Jinwei , Wu Changjun , Li Zhongsheng
Published: October 2018

The paper proposes a novel geometric error identification methodology for the tilting head of five-axis machine tools using double ball bar(DBB).Firstly, based on the motion condition of the tilting head of five-axis machine tools, three measurement patterns in Y direction, X direction and Z direction are proposed respectively. Then, the relative displacement equations of two balls of DBB in three measurement patterns are established respectively on the basis of homogeneous transform matrix (HTM) and multi-body system (MBS) theory. Finally, the geometric error parameters of the tilting head are identified totally. The presented method is universal and provides a reference for the error identification for the tilting head of five-axis machine tools.
Motion Error Analysis and Modeling Technology of CNC Camshaft Grinder
Authors: Fan Jinwei , Tao Haohao , Wu Changjun , Tang Yuhang
Published: October 2018

Taking certain CNC camshaft grinder as the subject its motion error analysis and modeling were studied. The movement forms and types of errors between the moving parts were analysed, the movement between coordinate systems of the adjacent bodies was used to express the movement between the two adjacent bodies, and the ideal motion equation and actual motion equation in case of errors between the adjacent bodies were set up. Actual motion equation between adjacent bodies was made and further extended to analyse arbitrary low-order body arrays, which provides a theoretical basis for studying the multi-branch CNC camshaft grinding machine error modeling. Complex multi-branch chain CNC camshaft grinder simplified was made as a simple multibody system, and corresponding body coordinate systems and motion reference coordinate systems for moving parts were established to calculate the corresponding transformation matrix between adjacent bodies. Moving parts of the machine were divided into “workpieces-bed” and “wheel-bed” two kinematic chains. The precision constraint equation of the machine is Pt = Pw in case of using errors influence, and the constraint equation was solved. It provides necessary conditions for study of CNC camshaft grinder error compensation. Results show that the machine precision is significantly improved after error compensation.
An Improvement in Welded Joint Using Vibration Assisted Arc Welding
Authors: Habib Mohammad Ahsan , Patwari Anayet U , Rakib Nuruzzaman , Pavel Mahmudul H. , Sanin Ahmed Y. , Salman Asif , Alam Fahrial
Published: October 2018

Welding is one of the important processes in mechanical engineering. In engineering sector, welding is a common phenomenon. To improve the quality of joining process, essential changes are necessary in regular welding process. According to the research in welding process, it has been found that vibration can improve mechanical properties of the joining section. However, welding joint quality varies with different ranges of parameters in different conditions. This study has performed to analyze those ranges of parameters in some selected conditions. Here are some input parameters like vibration amplitude, vibration frequency, welding speed and electrode angle are selected to analyze the variation in welded joint. For analyzing the results, output parameters – hardness and deposition rate are calculated. It can be seen that welding process assisted by vibration increases strength and quality of welding joint.
Extremely Thin Metal Foil Blades as Cutting Tools for Hard and Brittle Materials
Authors: Sakamoto Satoshi , Akaoka Sanshiro , Gemma Masaya , Kondo Yasuo , Yamaguchi Kenji , Yamaguchi Mitsugu , Yakou Takao
Published: October 2018

The manufacturing costs of semiconductor products such as silicon wafers can be reduced by decreasing the kerf loss. In addition, a decrease in the kerf loss leads to an effective utilization of rare materials, which is environmentally beneficial from the viewpoint of saving resources. This study aims to reduce the kerf loss during slicing hard and brittle materials. Therefore, the possibility of using an extremely thin metal foil blade instead of a wire tool in slicing was examined. Initially, grooving characteristics using a metal foil blade (thickness: 50 μm or less) was investigated. The main conclusions are that grooving with a metal foil blade is possible and kerf loss can be reduced. The groove depth tends to increase as the machining time and particle size of abrasives increase. The groove width is smaller when a thin metal foil blade is used and vice versa. However, if the abrasive particle size is too large, grooving becomes impossible. Since the wear of metal foil blade increases with an increase in the particle size of the abrasive, it is necessary to use an abrasive with a particle size that is suitable for the thickness of the metal foil blade.
Stress Analysis and Design of Main Reducer Housing Using Finite Element Method
Authors: Wang S.
Published: October 2018

The main reducer housing takes over the shaft loads from gear engagement and transmits to other components, such as differential, semiaxle and driving wheels, so the main reducer housing with enough strength and stiffness is very important. Some factors preventing it from failure need to be taken into consideration when design it. To design a main reducer housing with better performance, in this paper, FEA (Finite Element Analysis) is used to analysis the main reducer housing and to find out some big stress regions. Then, some modifications are proposed to eliminate those big stress regions and obtain a reliable main reducer housing. During the analysis process, an annulus model is built and the reaction forces between the differential bearing seats and axle housing are calculated to determine whether they contact with each other. Finally, some design methods and improvements of the original design main reducer housing are proposed. And numerical comparison results of the stress distribution of the original and improved main reducer housing validate the effectiveness of the proposed methods and modifications in this paper. Those stress analysis and modifications in this paper are time-saving and money-saving before mass production.
Increase of Critical Mach Number by Local Linearization Method and Airfoil Construction at Subsonic and Transonic Regimes
Authors: Bazgir Ali. S. , Takovitskii Sergey. A.
Published: October 2018

A symmetrical airfoil has been constructed by local linearization method. A single-point objective function is defined to check the convergence of the method. As an example, the nose and tail zone of supercritical airfoil is fixed and a flat line is placed between them. The optimizable element of the airfoil contour was conjoined with the nose and tail elements of fixed shape at the sections with coordinates xs1= 0.11 and xs2= 0.66, respectively. The optimizable part of airfoil (the fixed chord line) is divided into N=55 segments. The convergence of this method has been shown with the airfoil constructed with higher critical Mach number rather than the initial airfoil. Finally, this airfoil has been compared with the supercritical airfoil NASA SC (2)-0012 at M∞=0.76. At the second part, several airfoils have been constructed and simulated over different Subsonic and Transonic Mach numbers. Finally, the drag coefficient on constructed airfoils have been compared with supercritical airfoil.