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This paper study applicability of non-destructive method of impact echo for diagnosis of high temperature degraded plain concrete. Impact echo method is often used for detection of defects, cracks, and non-homogeneity in constructions. It's based on impact-generated mechanical wave that propagate through the mass of testing specimen and is reflected and partially absorbed by voids and surface. In this paper, we present results of an experiment where test specimens of dimension 0.1 x 0.1 x 0.4 m were created with usage of coarse aggregate 11/22 mm. Specimens has been divided to 7 sets. First set of test specimens were kept at laboratory conditions as a reference. Next six sets were heated up to 1200 ° C. After this heating, the specimens were cooled spontaneously and then tested by impact echo method. We used a steel hammer as an exciter of mechanical wave, which has been transferred to signal by the piezoelectric sensor. Then we analyzed this signal and we focused on transverse waves. Results from non-destructive tests were compared with results from destructive tests.

This paper illustrates how the amplitude and phase of back focal plane distribution can be recovered in a confocal microscope system from several intensity images in the image plane. These will have a wide range of uses for imaging and sensing. We believe this method is complementary to the V(z) technique where the sample is defocused. The field generated in the back focal plane may be processed by virtual propagation which averages noise in a highly efficient manner. In this paper, we demonstrate that the phase information on the back focal plane can be recovered using ptychography with no need to modify the optical configuration and employ an interferometer. This phase information plays a crucial role in sensitivity of surface plasmons resonance biosensing systems.

This paper studies the relationship between the value of temperature variation and the resistance value of each type of general resistors as well as also determines the temperature coefficient value of each resistor type. All obtained results will be compared to build a guideline for selecting the resistor to apply in any applications accurately and properly. Each type of 1 k-ohm resistor that has different power is used to study its properties and is controlled its temperature variation to be in range of 20 to 30 degree Celsius. An experimental setup to control the temperature variation of the resistors in this paper is that the resistors are put into an oil bath controlled its temperature after that measuring the changed resistance value of the resistors following oil temperature in the bath. The experimental result demonstrates that the temperature variation affects to change the resistance value of Carbon Film type the most but affects to change the resistance value of Wire Wound type with low power the least.

In this paper, we firstly explain the concept of surface plasmon resonance imaging and a main key issue in the field of localized SPR imaging, which is the trade-off between resolution and sensitivity. We will then explain how V(z) scanning confocal microscope can overcome the trade-off and enable us to make a localized detection of multiple analytes in small quantities. This paper provides a brief review on a chronological development of the confocal surface plasmon embedded interferometric microscope and highlights the key idea behind each developments. Theoretical detection limit of the confocal system is within a single molecule detection regime, where 100kD molecule can be detected with 100μJ of light in the confocal system. We also discuss some key challenges in achieving the theoretical limit, such as, microphonic vibration and slow scanning speed of the system and how to get around these challenges. Lastly, we discuss some possible future developments to improve the system.

The paper presents the background and objectives of a new research project carried out in the field of in situ gas turbine combustion. An extensive literature review highlighting the state-of-the-art in the field is presented. Several possible solutions for the turbine burner are also included. The objectives and the expected original contributions of the projects conclude the paper.

This paper shows the results of a project that investigated the humidity of the air in the ventilation gap of a green façade system. The systems which were investigated are made of aluminium troughs, aluminium modules, or fleece. These systems are mounted on metal rails. The metal rails connect the façade with the plants. This creates a curtain façade that is ventilated by air. The humidity of the air in the gap was investigated, and this paper shows the results of the investigation.

The overall energy performance of buildings is determined not only based on structural and material solutions of the building. Boundary conditions affect the results of evaluation of the energy performance too. This paper deals with buildings in the Czech Republic. The paper is devoted to the evaluation of energy performance of buildings under changing boundary conditions. This means the change of the intensity of ventilation, changes in the structures’ accumulation and influence of thermal connections.

In order to break through the limitation of the width of river, depth of water, channel and etc., it is an optimal choice to construct a long-span suspension bridge. In a suspension bridge, the main cable is the major bearing member; and the use of super high strength cable wire can lighten the dead weight and obtain an economical design. 1960 Mpa cable wire is adopted by an under-construction suspension bridge, namely Ni-Zhou Channel Bridge, for the first time in China. In this paper, taking the Ni-Zhou Channel Bridge as a case-study, comparative analyses on dynamic characteristic and seismic response of long-span suspension bridge with 1960 Mpa cable wire are performed. Firstly, dynamic calculating model for Ni-Zhou Channel Bridge is built and its dynamic characteristics are studied; then by using response spectrum and time history analysis method, seismic response of Ni-Zhou Channel Bridge is investigated on the basis of design response spectrum and artificial seismic ground motions; finally, the energy dissipation performances of a seismic protection devices (viscous damper) are also discussed. The results show that long-span suspension bridge with 1960 Mpa cable wire has a longer natural vibration period; the use of viscous damper can effectively reduce the peak value of bending moment in stiffening girder. This paper can provide references for the project’s construction.

In this paper an attempt has been reported to bring out the development and testing features of a laboratory scale induction system suited to bottled (fixed composition) PG powered IC engine. A four stroke, single cylinder, spark ignited engine was tested with a bottled PG at a Compression Ratio (CR) of 11:1 and engine speed of 1500 rpm from no-load to full load engine operation. Using suitable throttling devices, a 130 bar supply gas cylinder pressure was conditioned along with other devices to operate engine at Naturally Aspirated (NA) mode. The engine was operated close to stoichiometry condition. The engine supported a peak load of 85 % amounting to a torque of 11.89 N-m and brake power of 1.86 kW against a 2.2 kW gasoline mode. A power loss of 15 % was observed and it was attributed to 25 % lower mixture heating value and 13.33 % lower product to reactant conversion ratio of PG. Overall engine operation was found to be satisfactory. This paper also addresses the need for customizing PG-air mixer and zero pressure regulator.

Primary water stress corrosion cracking (PWSCC) has been observed in CRDM nozzles, BMI nozzles and other penetration nozzles. The industry has used the repair method of replacement of nozzles fabricated of Alloy 690. After the replacement of the nozzle, the structural integrity analysis of new nozzle and welds should be performed to ensure the pressure boundary compliance with the original design requirement. In this paper, the pressurizer top head instrument nozzle of PWR nuclear power plant is evaluated as a typical pressure vessel penetration nozzle. The results showed that the repaired nozzle satisfies the ASME Code design requirement and the crack growth of the postulated flaw in 40 years of the nuclear plant life is acceptable.PWSCC degradation mechanism has been observed in CRDM nozzles, BMI nozzles and other penetration nozzles [1]. In some nuclear power plants built in China earlier, such as DAYABAY nuclear power plant and QINSHAN nuclear power plant, PWSCC degradation mechanism has been found in CRDM nozzle welds which manufactured of Alloy 600 and welded of Alloy 82/182[2]. The repair of the degraded nozzles is the popular choice for the nuclear power plant owners. After the replacement of the nozzle, the structural integrity analysis of new nozzle and welds should be performed to ensure the pressure boundary compliance with the original design requirement. In this paper, the pressurizer top head nozzle of PWR nuclear power plant is evaluated as a typical pressure vessel penetration nozzle. Stress intensities were conservatively determined for pressure and applicable thermal transients and compared to the allowable values of the ASME Code, Section III. Thermal stress of the transients was obtained from 3D finite element model (FEM). Residual stress of J-groove weld was obtained from 2D FEM analysis and used for fracture mechanics analysis. All of the analysis showed that the repaired nozzle satisfies the ASME Code design requirement and the crack growth of the postulated flaw in 40 years of the nuclear plant life is acceptable.

Creep crack within weldments are very common in engineering practices, and the cracking location in these welding structures always appears at the HAZ location. The mismatch effect on the mixed mode creep crack is still not clear in these available literatures. The aim of this paper is to investigate the mismatch influence on the creep crack of mixed mode thoroughly. A mixed mode creep crack within HAZ is established in this paper. The leading factor that dominates the creep crack tip field under mixed loading mode is studied. The influences of mismatch effect on mode mixity, stress distribution and stress triaxiality are proposed. The difference of mixed mode creep crack and normal mode I or mode II creep crack are compared. The influence of mixity factor on the transient and steady state creep of crack tip are also analyzed.

Super capacitor, as a new type of power storage device, has been applied to various fields. This paper divides composite electrode materials of super capacitor into three main types. For each type, this paper analyses its performance, advantages and prospect. At last, a conclusion is drawn that it is a tendency to apply composite electrode materials to use for better performance capacitors.

Bearing fault signal presents obvious nonlinear and non-stationary characteristics, and local mean decomposition (LMD) method can adaptively process nonlinear and non-stationary signal. Quadratic phase coupling is one of the commonest nonlinear phenomena, and three-order cumulant diagonal slice spectrum is suitable for the extraction of the frequency components involved in quadratic phase coupling. In order to effectively detect the fault features of rolling bearing, a fault feature detection method of rolling bearing based on LMD and diagonal slice spectrum was proposed in the paper. Diagonal slice spectrum was applied in the extraction of the frequency components involved in quadratic phase coupling from the simulation signal, and it successfully extracted the quadratic phase coupling frequency components of the , and . The method was finally used in the detection of the bearing inner race fault features, and the results demonstrated that compared with diagonal slice spectrum of the PF component signals, the diagonal slice spectrum of the PF component envelope signals can identify fault characteristics much clearer and brighter. Meanwhile, the effective extraction of the inner race fault features verified the effectiveness and practicability of the method proposed in this paper.

This paper covers design diagrams and algorithms for determining the strain state of soil mass in case of its underworking. When tunnels are constructed in restrained urban conditions peculiar to megapolises, there is an acute problem related to the assessment of their influence on the existing above-and underground facilities. The strains of buildings and structures that occur as a result of underground construction work may have an impact on the operation reliability of these facilities. Russian regulatory documents in the area of underground urban construction strictly govern the basic parameters of the subsidence trough, such as maximum vertical subsidence, curvature, inclination, etc., for most of the existing underworked structures. Such facilities include both buildings and structures of various purposes above ground and different types of utilities (roads and railways, pipelines, cable lines, etc.). The method described in the paper offers the use of an integral quantity of "volume loss" when tunneling is performed by tunnel-boring machines. The "volume loss" term shall be understood to mean the distance between tunnel lining and soil mass, which initially occurs due to the difference between rotor diameter and lining outside diameter. There are also a number of other technology factors affecting the increase of this parameter, and their quantitative assessment is given in this paper. The method proposed in this paper makes it possible to promptly assess the impact of tunneling operations on the existing underworked structures with account of basic influencing factors.

Robotics has lots of use in the industrial world and has lots of development since the industrial revolution, due to its qualities of high precision and accuracy. This paper is designed to display the qualities in a form of a writing robot. The aim of this study is to construct the system based on data gathered and to develop the control system based on the model. There are four aspects studied for this project, namely image processing, character recognition, image properties extraction and inverse kinematics. This paper served as discussion in modelling the robotic arm used for writing robot and generating theta for end effector position. Training data are generated through meshgrid, which is the fed through anfis.

Published paper on modelling of propeller turbine blade and runner is not commonly found, especially those using Autodesk Inventor. One of them is titled CAD Modelling of Axial Turbine Blade using Autodesk Inventor. However, the road taken is quite complicated and should be repeated from the beginning whenever new geometrical characteristics of a new axial propeller turbine will be modelled. Currently, Autodesk Inventor has introduced the new tool that help sketching the spline lines either in 2D plane or 3D space simplifying the task of 3D modelling of propeller turbine blade, called Equation Curve. The Equation Curve tool requires the codes for creating the spline lines. To create the codes, two sources have been used: NACA report no. 460 and modelling methodology proposed by Milos in his paper. In NACA report no. 460, it is explained that NACA 4 Digit Series is created by combining mean line with the thickness variation curve of Gottingen 398 and Clark Y. This airfoil has 4 different lines with their own equation. The equations can be used for sketching in 2D plane. However, the solid model of the runner blade is formed from the airfoils in cylindrical surface. Then, as explained by Milos in his paper, the procedure is as follows: sketch the airfoil in 2D plane that is the tangent of cylindrical surface, move the airfoil to its center, rotate to its stagger angle, and project it to cylindrical surface. The result of this process will be the equations of lines in 3D space. Transform them to the Inventor codes. Input these codes to 3D Equation Curve tool to create the 4 lines for each cylindrical surface section of blade. Making the solid model of runner the following step is required: use loft command to create blade surfaces, use the stitch command to solidify, use the pattern command to create other blades, create hub, and lastly combine blades and hub. The solid model of the runner then is tested by simulating it using ANSYS Fluent. The hydraulic efficiency of the model is 85%.

Twin engines turboprop aircraft provides the most beneficial solution to meet the needs of short distance flight due to high fuel efficiency [1]. One of the emergency conditions which has to be considered for this type of the aircraft when one engine is out operating or one engine inoperative because it involves the safety of flight. Furthermore, a safe flight with one engine inoperative is regulated by FAR/CASR Part 25 and has to be complied during certification .Stability and control characteristics of a turboprop aircraft will change significantly if one engine inoperative condition occurs during cruise phase. The rudder and/or aileron deflections to counter the yawing and rolling moments due to the thrust of the operating engine must satisfy. Recognizing the importance of that consideration, this research will estimate the stability and control characteristics of lateral/directional in one engine inoperative condition on new turboprop 80-pax aircraft design concept.This paper presents procedures for estimating the lateral/directional static stability characteristics of a 80-pax turboprop aircraft during the conceptual design phase. The size of the rudder and aileron have to be iterated to fullfil the requirements at a condition when one engine is not operative. The rudder and the aileron deflections are estimated as functions of airspeed, roll angle, side slip angle and thrust setting. It will be shown in this paper that the required rudder deflection as well as aileron deflection can satisfy to balance the forces and moments due to asymmetrical thrust condition and the minimum control speed of the aircraft can be maintained as well.

The present paper proves the feasibility of a semi-automatic control system of high frequency ultrasound for welded plastic pipes, by ultrasonic methods. The paper presents the main existing types of plastic materials, the technological joining possibilities, the problems that may occur in welding and control and the reasoning of the chosen examination method. The theoretical size of the reference ultrasonic parameters for the propagation of ultrasounds through the flawless juncture. The samples were welded using electro fusion (EF) under different working conditions. The samples were assessed circumferentially, every 10 degrees, on different working frequencies. A semi-automatic control system was designed and developed. For the optimal working frequency, a set of 10 measurements was done, in similar working conditions, on the automatic control stand, in order to test the systems’ capability and the results’ repeatability. The measured values were compared with the limits considered to be admissible using Shewhart statistic control charts.

The present paper highlights the ultrasonic methods that can be used to detect the problems that can occur in special braze cladding. For this purpose, the sample production technology is described and the nonconformities that can arise during welding have been reviewed. The main nondestructive testing techniques are briefly presented motivating the chosen method for this study. Further, in the paper, the experimental procedure, materials and equipment used for welding are detailed. In the end, a comparison has been made between various parameters resulted from the nondestructive ultrasonic investigation. A validation for the presented method has been made through destructive examination by electron microscopy.

Stirling engine is a device that produces mechanical energy using heat from any source of energy, without the need of combustion of any fuel inside the device. Renewable energy sources, which are mostly low-temperature energy sources, can be used to produce mechanical and electrical energy in Stirling engines. The paper presents an overview of the existing prototype Stirling engines designed for using of low-temperature energy sources, including renewable energy sources. Commercial devices for electric power generation offered for use in home, usually do not exceed 1 kW. Using the Schmidt model, the analyze of influence of temperature working fluid in the expansion space (heater) on the efficiency and the electric power generated in the Stirling engine of alpha type has been presented in the paper.

This paper deals with an experimental analysis of hard rubber dynamic tests under finite torsion deformations. The experimental test rig was designed and composed for torsion loading of rubber under defined amplitudes, frequencies and temperatures. The present paper brings an amplitude-temperature analysis of isoprene-butadiene rubber ascertained by the use of the test rig. The mathematical rheological model of rubber was designed for phenomenological description and parametric identification of rubber.

The paper is oriented on the analysis of the ventilation systems in schoolrooms. Correct and sufficient ventilation of schoolrooms is very important because students and pupils spend in the schoolrooms the majority of their time in school. In our schools the ventilation is incorrect and insufficient. The biggest problem is winter period when the ventilation is provided only by opening the doors to corridor. This way, there is insufficient intake of oxygen, which causes distractibility and feeling of tiredness of pupils. In current schoolrooms we can use only natural ventilation and thus the schoolrooms have to be ventilated using windows. Therefore this research was focused on the comparison and the analysis of different systems of natural ventilation in schoolrooms. The experimental measurements were carried out in schoolroom, where the parameters of thermal comfort were measured in the different systems of natural ventilation with device Testo 480 which was connected to computer. Gained values of air temperature, air velocity and index PMV are presented in graphs. On the base of analysis of measured values were evaluated the systems of natural ventilation for schoolrooms. In the future, the mechanical ventilation in schoolrooms can be assumed, therefore the recommendation on modern energy saving system of mechanical ventilation is in the end of this paper.

Lightning has been the major cause of power interruptions in Malaysia. Malaysia is located near the equator having approximately 200 thunder days per year. It is known to be among the highest lightning activity country worldwide. TNB as the main power supply utility in Malaysia has made an effort to reduce the power interruptions via installation of Lightning Detection Network (LDN) in 1994. This paper presents the history leading to modern LDN that capture lightning radiation fields at multiple remote sensors. The network has undergone a series of improvement between 2004 and 2009 in response to evolving detection technologies and requirements. Recent analyses on actual performance of the current LDN are also summarized. The paper includes short and long term requirements for improving the lightning measurements needed to address some open scientific questions and fill the needs of emerging applications.

Distribution and power transformer is the essential part of electrical power transmission system. Abnormalities occur at the transformer can be interpreted and analysed to get the cause of faults, thus it can be further studied for monitoring ageing and condition of the transformer. A lot of studies have been done to detect as many abnormalities that can possibly arise in a transformer. For inexperienced user, it can be a bit of overwhelming to choose which studies that they can refer to. Numerous techniques and methods has been used for transformer monitoring till date and still being improved which includes: Common Electrical Tests, Power and Dissipation Factor Measurement, Partial Discharge (PD) Analysis, Frequency Response Analysis (FRA), Dielectric Response Analysis (DRA), Dissolved Gas Analysis (DGA), Dielectric Breakdown Voltage, Oil Resistivity, and Karl Fischer Titration. These techniques and methods are developed to monitor and analyse the common part of transformer which are winding, core, bushing, insulation oil, and insulation paper. This paper reviews the current improved techniques and methods in transformer monitoring according to the technology, accuracy, complexity, and cost for the past five years. A few methods and techniques can be appointed to each of classified user as a beginner, intermediate and competent. Finally, this paper suggests more improvement to be studied on the existing established methods. Some of the techniques can be combined to create a better accuracy and efficiency for fault identification, ageing estimation and condition monitoring.

One of the most important elements of a stand for measurement of a thrust generated by an underwater vehicle UV is a microprocessor measurement system. The system is responsible for processing signals from a force sensors and then for delivering processed data to a measurement system. The paper describes the microprocessor system which was built for measurement of a thrust generated by a biomimetic underwater vehicle BUV [4].The paper includes an introduction, technical description of the measurement system and at the end, selected results of its working.

Wireless network used in office is much cheaper than industrial-type devices. Using of office-type WiFi communication in industrial environment for exchange data between mobile platform (AGV) and base station is the core of this paper. The scope of research is data limitation flow in function of distance between system nodes and usability of office-type (low cost) equipment for establishes stable communication on industrial environment. Paper describes two experiments in two types of production environment. First one was realized in condition where several disturbance sources were active (like metal forming machine-tools, constant energy welding machines, electric overhead crane, high power electric motors, electronic inverters etc. All this machines contaminate radio environment around them and make serious obstacles for WiFi data exchange. Second experiment was executed in assembling hall of automobile production plant in which radio contamination is significantly lower.

This paper presents the analysis of the variety of methods regarding aerial guided bomb control during the ground attack on a moving target. Based on this method there was an earlier research regarding motion control of the three degrees of freedom gyroscope axis [1,2] during space exploration and discovered target tracking. Positive results obtained during that research led to conclusion that the proposed control method will be accurate to establish a control force for aerial bomb guiding. This method is based on the use of phase trajectories control deviations. Switching of the control forces in the particular phase plane points causes the deviations to decrease to zero and facilitates the proper trajectory of the bomb. This paper presents a switching algorithm, equations of kinematics and dynamics of a bomb flight-path and the variety of examples of a numerical simulations. Obtained results were presented in the graphic form.

This paper introduces a novel two-sleeve rotary compressor (TSRC) concept. The compressor mechanism is basically that of a rotary motion whereby the novelty lies in the usage of two rotating sleeves and a secured vane that has one end fixed to an outer sleeve and the other end to a rotor, respectively. The paper introduces the working principle and thermodynamic model of the TSRC compressor. The swept volume, the delivered pressure, the work and the power of the TSRC are formulated and analyzed. The compressor configuration and thermodynamic analysis are based on the 174 cm3.rev-1 swept volume with R134a as the compressed gas. The thermodynamic analysis reveals that the TSRC will perform well as refrigerant compressor and can be reliably adopted for refrigeration and air-conditioning applications.

The combination of solid insulation (usually cellulose paper) and liquid insulation (usually mineral oil) yield good dielectric properties at fair cost. However, arising concerns on environmental effect of mineral oil when leakage and its risk of fire has force researches for alternative fluids. One of the suitable options for replacement of mineral oil is biodegradable oil that is plant-based, high biodegradability, non-toxicity and high fire point. Some refining and modification to crude vegetable oils resulting to suitable transformer dielectric fluid such as BIOTEMP®, ENVIROTEMP® FR3 and PFAE (palm fatty acid ester). Application of these oils in small scale distribution transformers give positive feedback so far, hence, led to development of biodegradable oil-based large power transformer. Monitoring of the oil for power transformer is important to ensure its reliability and avoid unnecessary cost of failure. Dissolved Gas Analysis (DGA) is one of the methods for oil monitoring of transformer. This method analyzes oil condition to detect incipient faults so that relevant actions can be made before actual failures occur. This paper will review the hydrocarbon gases or known as faults gases for monitoring and faults diagnosis for mineral and biodegradable oil-filled transformer. Past works about DGA on biodegradable oil such as sunflower, soybean, and corn oil are analyzed. Any different on gases production of oil through different tests will be discuss further in this paper.

This paper investigates the possibility to individually balance the specific shaking forces and shaking moment of the slider-crank mechanism. The most common mean of balancing the slider crank mechanism is to use a counter mass. This solution is applied for almost every slider-crank mechanism used in commercial mechanical devices. However the nature of the mechanism does not allow a perfect balancing in such a way. The different nature of motions that govern the piston displacement and crank rotation imply that a counter mass can only statically balance the mechanism. An ideal dynamic balancing cannot be achieved this way. Therefore in this paper the excitations that act on the mechanism are split by the nature of motion that generates them and balanced accordingly. Two motions are defined, respectively the motion of the piston and the motion of the crank. The inertia force associated with the crank motion is balanced by building a dynamically equivalent system around the axis of the crankshaft while the excitation associated with the motion of the piston is balanced with a progressive spring with two rates.

This article describes a complex and generally applicable computational model for solving the frictional losses of directionally oriented and non-oriented sliding surfaces working under mixed lubrication regime. In the primary phase of this paper are described ways to get characteristics data describing rough surfaces together with the formula for determination of surface pattern directional dependence. Furthermore, formulae describing used contact model are listed and also the structure of the whole powertrain dynamics solution is briefly explained. In the closing section of this paper are shown and discussed results of several types of slide bearing analysis.

This Paper deals with the study of the potential substitution of Animal Tallow Methyl Ester (ATME) Blends for diesel as fuel for automobiles and other industrial purpose.The objective of this paper is to analyse the performance and emission characteristics of the animal tallow methyl esters and comparing them with petroleum diesel. The tests were carried out on a 3.5 KW, single cylinder, and direct injection engine. Engine tests have been carried out on 20% increase in steps of ATME blends with the aim of obtaining comparative measures of brake power, specific fuel consumption and emissions such as CO2, CO, HC, smoke density and NOx to study the behavior of the diesel engine. The performance and emission characteristics affected by various parameters like compression ratio which shows the major impact on engine performance by fuelling with biodiesel.Tests are also carried out on Variable Compression Ratio Engine B20 (ATME) which results in minor decrease in thermal efficiency with significant improvement in reduction of carbon monoxide and hydrocarbons when compared to diesel. The experimental result shows that 20% of blend shows better performance with reduced pollution on V.C.R engine.

In this paper are presented and analyzed a series of problems that are appearing during the CFRP machining. Due to their properties, the composite materials began to replace traditional materials (ferrous and non-ferrous) in a lot of industries leading out the development of new methods of machining or adaptation of the classic. Unlike traditional material, drilling in CFRP is more difficult due to inhomogeneity of the material, its high hardness but also due to lack of knowledge relating to how these materials behave. This paper investigates different types of tool wears as corner wear, welding, crater wear that are appearing in drilling operation due to the highly abrasive nature of the carbon fibers. Also, here is presented an evaluation that refers to the machined hole quality and describe defects as delamination, pull outs, fibers projections, pyrolysis and shape errors. The main goal of this paper is to verify the current status of technique in CFRP drilling in order to develop and produce a new drill geometry in a cooperation between the Technical University of Cluj-Napoca and the cutting tool company Gühring KG.

The aim of this paper is to highlight a method for improving laser beam efficiency. The laser weld bead profile depends on various parameters such as beam power, welding speed, wavelength of the laser radiation or the initial temperature of the material. Taking into account that laser beam welding efficiency is usually limited by synchronization of the laser source parameters, new methods were developed. In this paper is analyzed the influence of preheating the material and of the wavelength of laser radiation on the laser weld bead profile. Improvement in penetration depth was noted for preheating the material to around 140°C.

Friction Stir Welding (FSW) is the latest innovative and most complex process which is widely applied to the welding of lightweight alloys, such as aluminum and magnesium alloys, and most recently, titanium alloys, copper alloys, steels and super-alloys. Friction stir welding is a highly complex process comprising several highly coupled physical phenomena. The experiments are often time consuming and costly. To overcome these problems, numerical analysis has frequently been used in the last ten years. In this paper is presented a brief review of scientific papers in recent years on numerical simulation of Friction Stir Welding of aluminum alloys. The main elements analyzed by FSW simulation, and briefly in this paper are: temperature and residual stress distribution; work tool geometry (size and shape of the pin); distribution of equivalent plastic deformation; main areas resulted after welding; distribution of microstructure (grain size); parameters and optimization of the FSW process.

In the paper, we experimentally analyze a pneumatic actuator and possibilities of piston positioning. Paper shows mathematical model of pneumatic actuator. Actuator is experimentally tested and therefor experimental stand is assembled for the purposes of positioning of actuator piston. The changing parameters during the experiment are weight of load and pneumatic pressure. The results show how these parameters can have influence on precise positioning of pneumatic actuator. For experiment there is purposely used open loop control system. The aim of the study is not to show control method for positioning but to show influence of mentioned parameters.

The specific objectives of rehabilitation medicine are maintaining and recovering human body functions, as well as preventing dysfunctionalities by means of kinetic and orthotic techniques and a variety of equipment for support and adaptation. The latter are medical systems facilitating the exercise of muscles at constant or variable speeds according to professional recommendations. The paper presents and discusses the control of rehabilitation equipment designed for the passive mobilisation exercises of joints. The novelty of such equipment resides in its actuation by pneumatic muscles, as well as in its control by means of an SPC 200 controller and WinPISA software. The paper presents a number of examples of rehabilitation programmes and the corresponding motion graphs of the rehabilitation equipment sliding block.

This paper describes the basic characteristic of the in-pipe micromachine. Themicromachine is based on two masses impact principle. Its diameter is 10 mm, length is 45 mm andweight is 10g. The micromachine is composed of a electromagnet, a permanent magnet, a adjustingunit, a guide rod, a damping spring and bristles. The paper represents the methods of friction forcesidentification

In contextual evolution of the global economy and new technologies, quality, competitiveness, and cost engage companies to focus on continuous improvement and innovation. This approach is highly visible in the bearing industry, due to the emergence and improvement of existing and new types of bearings.The authors of the paper are engaged in a long-term research, which aims to improve the performance of heavy bearings, including identification of new constructive solution. The study is focused on the characteristics and constructive structure of the bearings cages in discussion.In this context, it is logical that the research focuses upon known bearings cages that are currently used [1], as well as unknown or unapplied constructive solutions which are the subject of patents.The critical analysis of various constructive cage solutions for bearings, intended or not for heavy bearings, is a valuable source of inspiration and information towards identification of constructive elements and characteristics useful to develop new technical solutions, by applying integrations, combinations, innovations and development processes [2].In the presented paper several patents are analyzed critically [3, 4, 5], in terms of constructive solutions, manufacturing complexity and presumptive operational energy consumption.

This article deals about the challenges of structural changes in manufacturing conditions. The objective of this paper is to present the modular workstations concept based on miniaturization and re-configurability trends. The article is aimed at problems of designing of production systems with a modular construction structure. The modular structure allows an individual and flexible adaptation to varying requirements but also the realization of low-cost solutions for creation of new or modernized production base. The goal is to present the example of modular workstations solutions that correspond with new designing approach. The specification of basics principles, which should help to designing flexible manufacturing systems, discussed in this paper are: modularity; integrability; convertibility; diagnosability; customization. The theoretical part provides an overview of fundamental design principles in manufacturing structures. In the first part of this article are discussed the specification of basic flexibility types in production system and the main impacts influencing design of manufacturing structures. The closing section of the article provides the specification of example solution of adjustable production platform with modular frame (called desktop factory).

The FDM technology is an easy solution when someone need freedom of design but with a high precision of manufacturing and so, one can built conceptual models or molds, engineering models, manufacturing tools, and functional testing prototypes. The problem addressed in this paper is to identify and investigate the possibility of design and the achieving sustainability of a temporary hand prosthesis used for supporting and immobilizing a broken bone. The research tries to highlight some common and distinct aspects specific to FDM printing technology. One of the objectives of this paper is to use the FDM technology in order to achieve a modern version of the classics splints or of the orthopedic cast. The prototype models proposed can be made vertically on a 3D printer with small motherboard and are easy to wear, attractive to children through its colors and can be made with a manufacturing low price.

In manufacturing industry there are many applications for the permanent joint of components of different shapes, but they are also very different in terms of chemical composition and structure [1, 2]. This paper is trying to find technological solutions of assembling by welding of two steels with totally different chemical composition, i.e. carbon steel S235JR + AR and austenitic stainless 316L. The process used for making the heterogeneous joint was Metal Inert Gas (MIG) with flux cored wire, numerically coded 137. The paper presents the effects of welding technology, through heat input, such as hardness. Variations of hardness values determined in the joint areas are presented, as well as the chemical composition of the welded joint obtained using the flux cored wire T 23 12 LPM 1/C1, according to EN ISO 17633 - A.

In the current automated high-tech world the applications and use of robot has become the vital role in all areas in industries and in common social applications. The mechanical design process essentials to improve and also it is a way to capable of giving consistent and fast efficient products. One way of altering the process is through reducing the manual work by systematizing the repetitive tasks using static analysis ways in the computer software. With a view to meet the purpose of inspecting the outer surface weldments in steel storage canister used to store the High-level fuel waste at nuclear industry with the help of Non-destructive testing (NDT) equipment. In this research work the new mechanical configuration of the robot arm was designed, and this arm was utilized to carry the vision camera at the end effector to capture the weld surfaces. This paper focuses the mechanical modeling of the manipulator mechanism and finite element (FE) method and analysis of the designed arm with different positions and specific load condition. From this study the statically balanced design of the robot was determined with three different positional conditions. The largest value of displacement and stress produced in the arm also discussed with clear FEA simulation results. In this paper mechanism of seven degrees of freedom robot arm is discussed.

Roll to roll process is one of the famous printing techniques that are possible to create graphic and electronic device on variable substrate by using conductive ink. Graphene is an example of material that can be used as printing ink which usually used in producing micro-scale electronic devices. Here, it is proposed that extending roll to roll printing technique into the multiple micro-scale printing fine solid line onto substrate by using graphene as a printing ink. Flexography is a high speed roll to roll printing technique commonly used in paper printing industry. And this study elaborates the feasibility of graphene as a printing ink use in combination of flexography and micro-contact or micro-flexo printing for micro fine solid line. This paper will illustrates the review of graphene in producing multiple micro-solid lines printing capability for the application of printing electronic, graphic and bio-medical.

This paper presents a new mechanical design of mobile robot which can travel in the condition of continuous varying environment, such as colon of human body. Especially, the human colon environment contains an intense diameter change. The suggested mechanical design is capable to adapt in wide diameter changing system by generating two basic motions, rotational and linear motion, with a single actuator. Prototypes is fabricated, and tested result is presented in this paper. Also, experimental result is compared with the mathematical model of the mechanism to verify the feasibility of the proposed mechanism.

This paper presents a case study of water flow over the chute spillway type for the Mengkuang Dam expansion project. It governs the surplus water from the dam to the downstream area. However, flows were driven by gravity along the curvature and vertical direction which cause unpredictable flow direction along the chute. Its cause’s thickening of turbulence, changing the velocity, pressure and depth of the water along the spillway. This study was simulated using a physical model with geometrical scale of 1:20. After some test conducted on the spillway, eleven locations on the spillway were selected for the test based on observation for the study. For each location, there were five points in a line with equal distance. Manometers were installed on six locations of the spillway. The water level, velocity and pressure were measured at every point for 100, 1000, 10000 years and PMF design discharge of the spillway. Several critical occurrences on the spillway such as turbulent and cross-wave were presented in this paper.

This paper discusses the implementation of an adaptive fuzzy autopilot for a scale ship model using a Fuzzy Model Reference Learning Controller (FMRLC). Initially, a fuzzy singleton model of the scale ship model is obtained from experimental input and output data gathered from the turning circle manoeuvre. After that, the paper describes how to design a Fuzzy Model Reference Learning Controller (FMRLC) for controlling the directional heading of the scale ship model. At the end, results of the implementation of the adaptive ship autopilot are showed.

When using the laser displacement sensor to measure distance, there is a deflection angle which exites between the direction of the laser beam and the direction of axis, this deflection angle has an impact on the final measurement result. This paper presented a calibration method of the laser beam’s direction, designed calibration device and ceramic calibration plate. In the process of calibrating, laser displacement sensor moves along Z-axis and Y-axis of machine, CCD camera takes the image of the spot projected by laser beam on the calibration plate, then calculate the laser beam’s direction based on the movement distance of laser displacement sensor and the spot’s position on calibration plate. Depend on the Mikron five-axis CNC machine tools, this paper describes the whole calibration process in details, the feasibility and accuracy of the method has been verified by experiment. Experimental results show that when the machine tool’s accuracy is within 0.002mm, the calibration error of laser beam’s direction can be controlled within the range of 0.05°.

An experimental investigation was presented in this paper on reinforced concrete box beams subjected to shear, torsion, and bending moment strengthened by carbon fiber reinforced polymer (CFRP). Eight box beams were cast and separated into two groups according to two different torque-to-shear and torque-to-bending moment ratios. Three box beams from each group strengthened by CFRP in different configurations and one control box beam were tested. The main parameters of this experiment were the different ratios and configurations, including U-jacket layers and U-jacket strips with or without longitudinal strips. The cracking and failure mode, effect of wrapping configuration, torsional capacity, and behavior of the different torque-to-shear and torque-to-bending moment ratios were studied in the paper.

The model for the analysis of the gear pump work designed for the hydraulic systems was made for the 3D non-stationary two-phase flow using CFD software. In this paper, we made the simulation calculation of the pressure surge when opened between gear space in the discharge tube while the liquid is pumped. At the same time, we detected the pressure, velocity fields and the volume fraction of the steam in the gear pump space. The paper presents the resultant of the forces and the moments acting on the gears and possible sites of cavitation in the area of the gear pump and on its bearings. All the obtained results have been examined in the practical manufacturing processes.