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The results of impact testing of welded joint specimens taken from a welded plate made of P460NL1 steel are presented in this paper, and analysed with regards to the cooling time t8/5, that was previously calculated. The aim was to determine how the cooling times that were measured, some of which were below the minimum required values, affected the toughness, in terms of total impact energy and its components, crack initiation and crack propagation energy. In addition, this analysis included the effects of temperatures measured at the opposite ends of the plate during the welding process, since this had also affected the cooling times for each welding pass. After observing the differences in total, crack initiation and propagation energy between the tested specimens taken from different parts of the welded plate, it was determined that the specimens from the part where the higher temperatures were measured had shown better, more uniform results, whereas the average total impact energy for specimens from both groups were very similar. It was also noticed that the ratio of crack propagation to crack initiation was more favourable (greater) in the case of specimens from the second group (with higher temperature), as the values of crack initiation energy decreased slightly and the crack propagation energy increased.

The paper presents studies carried out in order to determine the causes of destruction, by cracking, of a crankshaft from the composition of a tractor used to process soil.Experiments were carried out in two directions, namely a step by step study on the degraded area and a investigation into the operating conditions of the machine, on that specific work cycle.The degraded shaft was investigated visually at a magnification of 10x and by hardness tests on the areas with embrittlement cracking.Hardness test enfolded large variations (in hardness), of up to 40%, leading to a high sensitivity to cracking by mechanical fatigue, induced by the structural tension concentrators. However, hardness examination did not reveal areas of shaft degradation due to fatigue, which determined us to study the operating conditions. The shaft cracking occurred during soil processing, using a multilayered plow and in difficult exploitation conditions.Variations of mechanical characteristics of soils in the area of ​​operation of the machine, is relatively large, fact which corroborated with the lack of safety elements when overloaded, of the endowment of the tractor-plow system, led to the overcoming of the permissible load, which on a background of high hardness material, determined the embrittlement cracking of the crankshaft. Research performed highlighted, for the area in which the machine activates, the necessity of introducing in the power-generating system of safety and protection elements to prevent the destruction of components.

Research conducted aimed to compare the hybrid ultrasonic-thermal cutting technology with the classic thermal cutting one. The experimental program was carried out on the ISIM designed hybrid equipment, operating at a frequency of 35 KHz, with a cutting geometry of the ultrasonic horn - sonotrode and the thermal anvil designed specifically for the task at hand; the first phase of the experimental program was developed on the thermal cutting module, the second one was performed on the US-thermal hybrid module, both modules being part of the hybrid cutting equipment designed and patented by ISIM Timisoara. The research performed in this present paper, intends to highlight the benefits of the hybrid cutting technology when compared to classical thermal cutting, in order to process two types of materials with different specifications and dimensions. After visually inspection cut materials have been then compared with automotive seatbelt quality standard IATF - International Automotive Task Force 16949. Experiments highlighted that hybrid ultrasonic-thermal cutting process has a significant influence on the quality of processed materials when compared to classic thermal cutting process, which in some cases makes the materials unsuitable for use in the automotive industry. The paper further presents two types of technology data sets suitable for 2 types of materials and up to automotive industry requirements.

A grapple is a device that includes at least one gripping arrangement. The gripping arrangement is configured to grip and traverse objects so as to reach a desired location on site and to anchor it, therefore allowing the work to be carried out. [1] A method for controlling the fill volume of a grapple, such as a bulk-material crane grapple which includes at least one hoist-and-closure unit, may include adjusting the fill volume of the grapple is during the grapple closure process by adjusting/controlling the grapple hoist height. The grapple hoist speed and/or grapple hoist height may be the controlling parameter for the adjustment of the fill volume of the grapple. [2]Grapples geometric configuration is established by calculating the useful load mass. In the experiments performed in the present paper the load mass was 3000 kg. In exploitation, in cases where relatively low density materials, if compared to standard materials, are being moved/processed, changes to the volume capacity must be done; [3] changes that need to be correlated with the new materials and the exploitation conditions.The tractor attachment is a grapple assembly, and the grapple assembly kit includes a mounting assembly, a plurality of clamping units, and a plurality of support units. [4] A connection system for coupling an claw to a work vehicle includes a receiver assembly that needs to be implement and configured to a connector assembly of an arm of the work vehicle. [5]The solution developed by the authors consists in prolonging and consolidating the active elements of the grapple, by equipping it with additional elements that take and process load tensions, in the present case hard wood logs; and a consolidation and protection system that protects it from wear, that mostly appears when the hook crane repeatedly hits the ground in order to collect the deposited logs.The additional elements for handling and processing logs are made out of low alloyed steel, thus by configuring the tips we assure the good gliding of processed materials on the active/used surfaces. The self-protection system to wear is made out of boron micro-alloyed steel sheets that have hardness values up to 500 HB. Joining the grapple ensemble with specialized elements was performed through welding.

The paper presents technologies for the manufacturing of modulated bi-metal elements, used as interchangeable reinforcement, according to patent RO129865. The bi-metal was developed by surface build-up of functional layers that have increased hardness, on a low alloyed steel substrate, so as to ensure maximum lifespan in exploitation. Welded layers deposited on active areas has a thickness of 3 mm and have high hardness (about 50-60 HRC) in order to ensure a good resistance to wear by abrasion, possibly combined with fatigue, erosion or corrosion. The modulated elements sizes are equal to or higher than the wear additions, up to 10%, being dimensioned on the principles of preventive-repetitive maintenance. The interchangeable bi-metal elements are welded on the steel components of machines, used for hot or cold processing of parts and semi-finished products manufactured in series.

Accidents, such as storm surge, typhoon, non-normal impacting and other abnormal operating conditions will all cause damage to the structure of piled wharf. To improve the bearing capacity of structure and extend service life, it is need to detect, evaluate and reinforce the piled wharf. This paper analyzes different reasons and ways of destruction then puts up some detection methods for piled wharf’s different components. The evaluation procedures and steps of piled wharf are also disused and mechanism of various reinforcement methods are researched in the same time. The results of this study can provide reference for the detection, assessment and reinforcement of piled wharf structures.

A self-study harmony search (SSHS) algorithm for solving unconstrained optimization problems has presented in this paper . SSHS employs a novel self-study strategy to generate new solution vectors which can enhance accuracy and convergence rate of harmony search (HS) algorithm. SSHS algorithm as proposed, the harmony memory consideration rate (HMCR) is dynamically adapted to the changing of objective function value in the current harmony memory. a large number of experiments improved that SSHS has demonstrated stronger convergence and stability than original harmony search (HS) algorithm and its two improved algorithms (IHS and NGHS)

Aim of this paper is to present a numerical method for modeling of the so-called “equivalent box section fiber beam concrete element”. By comparing hysteresis curves of specimen of the concrete structure plotted with rebar beam with those plotted with the equivalent box section beam under a set of loading cases, the following conclusions are obtained: 1) The modeling technology of equivalent box section beam can overcome the difficulty which the rebar in beam can only be used in static calculation, and the fiber beam element can be applied to dynamic explicit analysis; 2) By comparing hysteresis curves which are plotted by the rebar beam with those obtained with model of equivalent box section beam, it is found that results are in good agreement for a specific typical loading case; 3) By comparing hysteresis curves of the equivalent box section beam with experimental data under given loading case, numerical results indicate that numerical results obtained with proposed modeling technology can fit the experiment phenomena very well.

Service-Oriented architecture (SOA) has increasingly becoming an architectural evolution as one of the software design principles. This paper proposes an architecture design of an online collaborative agreement signing system based on SOA. The advantages over traditional designs are loose coupling, scalability and flexible combination of services. Web service model of the proposed solution is also described. Electronic seal and digital watermark are discussed as the domain knowledge as well. Sample software based on Windows Communication Foundation (WCF) technology on .NET platform is introduced in the last part of the paper.

This paper expounds the applications of WPC in the design of multimedia speaker box, and analyzes the advantages of WPC as the material of multimedia speaker box from three aspects: excellent acoustic performance, easily processing and environmentally friendly. It puts forth effective theoretical support for the applications of WPC in the design of multimedia speaker box.

In this paper, the hot compression tests were performed to study on deformation-induced pearlite transformation in vanadium microalloyed eutectoid steel. The results showed that volume fraction of deformation -induced pearlite were higher and the pearlite were spheroidized better under lower strain rate and higher strain in vanadium microalloyed steel. Ferrite grains and granular cementites were further refined through vanadium microalloying combined with deformation-induced pearlite transformation .Vanadium dissolved in γmatrix could retard deformation-induced pearlite transformation under low strain, vanadium carbides precipitated due to strain-induced precipitation eliminate the retardation when the strain was increased to a certain extent. Under heavy deformation, ferrite grains and granular cementites in vanadium microalloyed steel were finer compared with vanadium free steel.

This paper represents a comparative study of the different weave structures of jute woven fiber reinforced unsaturated polyester resin (UPR) composites. The weave structures were selected as plain (1/1), twill (2/1), twill (3/1) and basket (2/2). Composites (50% fiber by wt.) were prepared by using hand lay-up technique. The mechanical properties such as tensile strength (TS), bending strength (BS) and impact strength (IS) of the composites were evaluated and compared. It was found that basket weave/UPR based composite showed the highest mechanical properties. The optimum value of TS, BS, TM, BM and IS of the composite were found to be 47 MPa, 80 MPa, 1.4 GPa, 4.8 GPa and 27 KJ/m2.To find out the effect of yarn density on mechanical properties of the composites, 2/1 twill structure was selected and found significant improvement in the mechanical properties with the increase of Ends/Inch (EPI) and Picks/Inch (PPI) in the fabric. Water uptake and degradation behavior in aqueous medium of the composites was also observed.

Dredging is the available method to clarify eutrophic lake water for some engineers in recent years. This engineering may cause at least two negative influences on water environment, (a) pollution by dredging would occur during the operation, and (b) long-term effect degrade with some lake become dirty subsequently. Changes of the concentration of TP after the engineering of dredging are the focus in this paper. The content of total carbon (TC) and total nitrogen (TN) change at the same time for different original concentration of TP. Five grade original concentration of TP was simulated and the changing law was presented with the process of duration (D) and the change of temperature (T) as the independent variables. The results indicated that the concentration of TP decreased almost to 50% of their original ones respectively. But the changes of concentrations of TN and TC abide by the distinguished rule.

CVD diamond films have been used in many high-tech fields with the industrial and scientific developments, while the lagging of the polishing technology for the CVD diamond films has limited their widely applications. This paper presents a high-efficient low-cost wheel-grinding technology for CVD diamond polishing, and the two key techniques of this technology are introduced in detail based on thermo-chemical polishing technology. Furthermore, wheel grinding technology exhibits a promising perspective for the widely application in the diamond films.

In this paper is presented a study regarding the possibilities of commandinga virtual robot using a haptic interface. In order to demonstrate the functionality of this concept, a dedicated device with 1 DOF was developed. This device consists of twin motor-gearbox able to acquire and transmit the angular data of the shaft and return a haptic feedback corresponding to the robot movement. The proposed haptic device makes it possible to command one joint of an industrial robot and can be used as an essential component for the development of an exoskeleton for human arm and is able to generate a haptic interaction for all the joints. The exoskeleton solution will allow a structural similarity between the haptic device and an articulated robot arm. The test results with haptic feedback scenarios show that the proposed system can help inexperienced users to handle robot operation and programming tasks in an intuitive way.

With the example of the parametric CAD system of the rolling bearing, the parametric design method to the second development of the AutoCAD system based on VB by using extra database is introduced in this paper. This system can visit the extra database by ADO technique, complete the total design of the system, create the system database, realize the parametric design and parametric drawing.

This paper proposes a robust position controller for a precision mechatronics system, based on the quantitative feedback theory (QFT), to achieve high accuarcy and consistent tracking performance even in presence of considerable structural dynamic uncertainties and external disturbances. Tthe dynamic characteristic of precision mechatronics system is experimentally identified with close-looped identification method, taking account of system uncertainties, and then a QFT controller is designed. Simulations are carried out to validate the efficience and effectiveness of the proposed controller.

The hydraulic cylinder should be safety released in high-pressure situations, the release valve system is presented under such situation in this paper, which can release the high pressure from the hydraulic cylinder, in order to validate its feasibility, the simulation model of pressure release system is established in AMESim, the pressure release process of which is studied, the results show that the pressure relief system can release the high pressure of hydraulic cylinder smoothly, the pressure release system verifies the pressure control performance of control system, some of the parameters or factors of pressure release system are analyzed.

This paper examines and present the findings of the physical and mechanical properties of concrete containing rice husk ash (RHA), and the blend of rice husk ash with calcium carbide waste (RHA-CCW). Concrete cubes, cylindrical and beam specimens containing different percentages of RHA and RHA-CCW by weight of cement (5, 10, 15 and 20 %) were cast. Compressive strength test was carried out after the specimens were cured in water for 7, 14, 28 and 56 days. Test for tensile and flexural strength was carried out after 28 days curing. Initial and final setting time test was carried out on mortar specimens with the same percentage of RHA and RHA-CCW. Bogues model was used to determine the elemental and compound composition of cement when blended with the RHA and RHA-CCW. From the results obtained, the compressive strength of RHA-CCW concrete increases as cement is partially replaced with RHA-CCW content, with the maximum strength attained at 5 % replacement. RHA concrete attains it maximum strength at 10 % replacement. The maximum compressive strength results obtained for both RHA and RHA-CCW concrete were higher than the strength of plain concrete (0 % replacement) by 1.1 % and 14.7 % respectively. Interestingly, results obtained for the tensile strength also shows a similar pattern of strength development with that of compressive strength. The flexural strength properties of concrete was improved upon when RHA-CCW was used in concrete compared to RHA. The results of setting time test for RHA mortar showed a decrease in setting time, while the reverse was the case for RHA-CCW mortar. In conclusion, provided adequate curing is maintained, the used of RHA-CCW gives a better performance in concrete than RHA. However, they both perform better in concrete than the plain, and can be used as additives in concrete production.

The paper systematically analyzed the relationships between geological conditions including strata and magmatic rock, etc and lead-zinc deposits, and found out their control action and features on Pb-Zn and Fe-Sn deposits, then established the comprehensive prospecting model for Pb-Zn and Fe-Sn deposits that consisted of geological, geochemical and mineralization information, which will provide theoretical basis for predicting the lead-zinc metallogenic deposits within this metallegenic belt.

This paper aims to explore the construction of monitoring system of autonomous learning for college English. Dynamic development of autonomous learning was explained briefly. It also discussed connotation and features of the monitoring of autonomous learning. Finally, the monitoring system of autonomous learning was created after analyzing the current situation of students’ autonomous learning activities. It points out that interaction between inner and external monitoring system is beneficial to the progress for English learners; Joint efforts of all of the elements in the system contribute to the efficiency of college English teaching.

Studies have revealed that wood ash cement concrete just like other pozzolanic cement concrete has lower early strength compared to plain cement concrete. Nanoparticles have been found to improve the early strength of concrete due to its small size and large surface area. This paper reports the findings on influence of nanosilica on the workability and compressive strength of wood ash cement concrete. Wood ash was obtained as a waste product from Ladoke Akintola University of Technology (LAUTECH) bread bakery, Ogbomoso. Biological synthesis of nanosilica using kola pod extract and silica precursor (1:5) was conducted at Nanotechnology research group laboratory at LAUTECH. The chemical composition, specific gravity and grading of wood ash, fine and coarse aggregate used were determined. Concrete with 10% wood ash replacement for cement was produced using 1:2:4 mix proportion and water to binder ratio of 0.5. Nanosilica was added at 0.5, 1.0, 1.5 and 2.0% levels. Concrete with no wood ash and nanosilica served as the control. Workability and compressive strength of the plain and composite concrete were determined. The results showed that concrete workability was enhanced with introduction of nanosilica. The compressive strength also increased with the addition of nanosilica. Maximum compressive strength of 27.53MPa was achieved at 90 days with 1.5% nanosilica addition. It was concluded that nanosilica enhanced workability and improved both early and later strength development in wood ash concrete with 1.5% as the optimum addition.

The papers aim is to detail temper bead realization, as a possible solution to the removal of heat treatments. Applying temper beads could be a solution for repair, in case surface heat treatments are required, provided they are correctly applied. The paper presents the main ways of applying temper beads, presenting in the same time what the outcomes could be in case of not respecting the prescribed work sequence.

The paper will try to evidence the importance and the role of the Welded Structural Designer and explain also the critical joints to the dynamically loaded welded structures susceptible to fatigue. In case of the important structures the decision of the Welded Structural Designer is essential, because his decision allows the change the type of joints, the type of materials.

In recent years, due to its extraordinary qualities, friction stir welding process FSW has found its utility in more and more industrial applications in fields such as: aerospace, aeronautics, naval, automotive and railway. The paper summarizes several achievements in the FSW joining of couples of similar and dissimilar materials used in the automotive industry. There are presented aspects regarding the welding of ferrous metal materials (DD13), couples of non-ferrous metallic materials (Al Cu range) and steels with aluminum. The behavior of FSW of material couples in terms of analysis of microstructural improvements and mechanical characteristics is analyzed. The preliminary results obtained have shown that the FSW process can be successfully applied to the joining of the approached material couples, but with the use of optimized welding tools and technologies.

Turbine and generator rotors and shafts undergo high stresses during regular working life and, from a safety and operational aspect, are the most significant components of a power generation system. Depending on the appropriate operating conditions, like temperature and/or corrosion the, shafts can be fabricated out of low/high alloy heat resistance material or of low alloyed, highly toughened material for different application. Despite known good practice and developed operation procedures, the failures of shafts sometimes occur. The right and well-defined failure analysis is the basis for feasibility analysis of repair method in the power generating industry. The analysis of direct and indirect costs of repair after the failure analysis as well as the analysis of the repair and post-repair conditions of the repaired element is the vital for decision on the key question. Is it possible to repair this element and what is the optimal repair strategy? This paper compares and analyses two approaches, by weldability analysis and weld cycle simulation, in order to determine welding feasibility analysis of cracked hydro turbine shafts.

The paper presents the current state of researches carried out in order to improve homogeneity of mixtures for metallic powders; our priority is those with different participation in the mixture, by mechanical alloying. Mixtures of this type are used in the production of welding and related materials.Recently, research has been done to improve deposited metal properties by welding with coated electrodes, by depositing nanostructures, with uncertain results due to the low degree of homogeneity of blends involved in the electrode coating.The performance enhancement method for coated rods, developed by introducing in their coat activating precursors, used for brazing, is well known. The solution to improve the degree of homogeneity of alloying systems by mechanical alloying has been successfully applied for the manufacture of coated electrodes and those tubular with a composite core which are deposited by manual welding or TIG welding, type Fe25% Cr-4% W-V-Ti-La. The grouping of powder components for mechanical alloying was done in such a way that, finally, we have groups with the granulation, respectively specific weight, close and a low potential of segregation.The method of mechanical alloying of the components was used in the manufacture of coated rods in order to improve the fluidity of silver-rich buffer layers deposited in order to favor the diffusion phenomena of brazing alloys in the base materials.Testing the homogeneity of the alloying systems was performed indirectly by metallographic analysis and sclerometric tests.

The ultrasound processing is in continuous development, always bringing better technological solutions. Ultrasonic welding occupies an important place within this category of processing. The present study focuses on some piezoceramic materials that represent the active elements in the structure of the required energy generator on which ultrasonic welding is based in fact. Using the analytical method of investigation, several aspects of piezoceramic material structural behavior during the exploitation were followed, both at macroscopic and microscopic level. Some causes and effects of changes to their functionality have been analyzed. The paper concludes with observations and recommendations on optimizing the manufacture and use of piezoceramic materials intended for converter construction for ultrasonic welding.

Existing equipment units in specialized industry market, used to process composite polymeric materials, are made with constructive solutions dedicated to specific applications, actual cutting operation are being achieved by thermal effect often resulting in burns of the material on the working area, the version proposed in this paper, a hybrid technology using ultrasonic energy assisted thermic energy, proved to be an excellent solution.The technical problem solved by solution presented by our technology is represented by real market necessity of providing clean processing – in this case cutting and sealing, of composite polymeric materials, in the form of strips, which must correspond in dimensional and qualitative terms to specifications in product documentation, textile tape, used in the textile, food, medical and army industries.

We approached a new hybrid technology that integrates ultrasonic energy with FSW welding. By integrating ultrasound in the FSW process, a number of benefits are expected in terms of welding quality, forces and tool life. Our research aimed at developing a new technique of friction stir welding assisted by ultrasonic energy, namely FSW-US, which can improve the process, it can contribute to the decrease of forces that develop during the welding process and can increase the quality of welded joints. Metal welding and processing technologies that use ultrasonic vibrations, either as a primary source to achieve prescribed performance, or as a source of assistance to improve the efficiency of the operation and product quality, are currently being researched or discussed in the international scientific environment. The present paper analyzes the effects of overlapping ultrasonic vibrations with heat generation, temperature distribution and material flow generated by applying the FSW process. Mechanical effect plays a dominant role in the welding process assisted by ultrasonic vibrations, while thermal effects are insignificant. Overlapping ultrasonic vibrations on the friction stir welding process can produce a stream of improved plasticized material, increases the welding speed and efficiency, it can also improve weld quality by increasing the flow / volume of plastic material around the tool. [1]

In certain welded constructions (e g. trails pipes) the weld root is no longer accessible after its completion. As a result, the weld root defects cannot be visually observed. Under these circumstances the root must be examined with ultrasounds on the other accessible side of the seam. The paper .presents the results of the flaw examination which was subject to an pipe, butt welded, made it with coated electrodes

This paper presents experiments regarding the welding with electron beam of Ni based amorphous ribbons produced by "Planar flow casting" method with the aid of "Politehnica" University of Timisoara equipment. Welded samples were performed in partnership with Graz University of Technology, Institute of Materials Science, Joining and Forming, using the electron beam welding equipment “Chamber Machine EBG 45-150 K14”. The welded joints were analyzed by SEM, EDX, XRD in order to optimize some technological parameters to avoid deterioration of the amorphous ribbons during the welding process.