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The series resistance (Rs) controls the device performance significantly and for organic diode, the typical value of Rs is quite high. There are not many reports on the investigation of the high value of resistance in organic diodes. In this paper, we report that the trapping of charge carriers which is an important parameter to control the charge transport mechanism in organic solids is responsible for this high value of series resistance. In this paper effect of trap energy on Rs has been studied in the presence of TiO2 and ZnO nanoparticles on Phenosafranine (PSF) dye-based organic diode. It is already reported that by incorporating nanoparticles, trap energy is reduced which in turn increases the conductivity and efficiency of the device. So it is expected that trap energy has a strong influence on Rs. In this work we have measured Rs by using the Cheung Cheung method and the trap energy is also measured by analyzing the dc current. The value of Rs is related to trap energy. The extracted values of Rs are about 250.8 KΩ, 108.0 KΩ, and 98.4 KΩ respectively for only PSF, PSF+ZnO, and PSF+TiO2. It is also been observed that by incorporating nanoparticles the trap energy is reduced. The estimated values of the trap energy are about 0.090eV, 0.078eV ,0.072eV respectively for only PSF, PSF+ZnO, and PSF+TiO2. It has been observed that lowering of trap energy by incorporating TiO2 and ZnO reduces the value of Rs.

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.

The purpose of this research is to analyse the technological and economical aspects of making 3D print pieces to produce functional parts and subassemblies for abrasive waterjet processing equipment. The authors of this paper intend to make a clarification on the technological and economic approaches of material that can be used to make such a reference in terms of economic efficiency and technology. In the paper are analysed all the aspects involved in generating the necessary elements on the mechanical side of them by FDM (Fused Deposition Modelling). The paper is structured in a five chapters in which it is presented in a logical order the analysis of the materials that can be used in the mentioned technological field, the technological parameters specific to the analysed process, the method of generating the parts and their realization from a practical point of view and presenting the main economic aspects that involve the manufacturing costs of specific parts through 3D printing technology for components of water jet processing equipment with suspension abrasive media.

The isogeometric formulation seems to be advantageous especially when it comes to curved geometries such as curved beams and shells. In this paper, the NURBS isogeometric formulation of beam element is presented. The same basis functions are used for both geometry description and unknown approximations so there is no accuracy loss caused by a geometry approximation. The element is based on Timoshenko beam theory which enables the use of the element for both thick and thin beams, nevertheless in case of thin beams the shear-locking phenomena is observed. In the paper it is shown that the reduced integration is insufficient for locking removal and capability of Discrete Shear Gap (DSG) method to unlock the elements is examined. For clear demonstration of locking-removal techniques the implemented element is first tested for the case of straight beam, then the performance is demonstrated on the curved geometry.

This paper presents a computer vision algorithm for achieving fast collision detection. This paper presents a solution for a highly adaptable solution. The acquired depth images are used to calculate a possible collision with industrial machines. Using a robot model and marked cells on the floor any robot cinematic configurations can be checked for collisions with human detected in the workspace. The proposed approach is applicable to a variety of industrial applications where operators are under threat of accidents.

The topic of this paper focuses on the virtual interactive prototyping and augmented reality prototyping. The prototyping of the manufacturing systems is of utmost importance. The prototyping phase is also important for maintenance for manufacturing systems. The paper propose a new approach taking into account several key ideas concerning the manufacturing machine components. The overall objectives of this paper are to propose new models and techniques for virtual prototyping and augmented reality.

Worker information systems provide the right information at the right time in a lean way. In this paper, the need for an integrated feedback system with formalised text parts is exposed. To meet the disadvantages of a lack of feedback, two important points are identified: involving of workers and guaranteeing a high information quality. Several approaches show that workers have to be included into an early stage of product development process to improve product details and especially assembly scenarios. Also, workers get an idea of their contribution to a zero-waste production. If more information is created, the quality gets more important. It is explained what quality criteria should be considered. Technical realisations for a feedback system close this paper.

This paper presents an introduction aboutC3Botsproject which aims to design collaborative, cross and carry mobile robots. In this project it is considered to design an innovative robotic system based on modular entities with a simple mechanical architecture able to collaborate to ensure object co-manipulation and transport. The resulting multi-robot system is calledC3Bots. In this paper we present the first version of this system using a parallelogram mechanism for co-manipulation and the realized prototypes which are going to be used for first experiments.

The paper reports on the activities of the RILEM technical committee “Reinforcement of Timber Elements in Existing Structures”. The main objective of the committee is to coordinate the efforts to improve the reinforcement practice of timber structural elements. Recent developments related to structural reinforcements can be grouped into three categories: (i) addition of new structural systems to support the existing structure; (ii) configuration of a composite system; and (iii) incorporation of elements to increase strength and stiffness. The paper specifically deals with research carried out at the Bern University of Applied Sciences Switzerland (BFH), the University of Minho Portugal (UniMinho), and the University of Trento Italy (UNITN). Research at BFH was devoted to improve the structural performance of rounded dovetail joints by means of different reinforcement methods: i) self-tapping screws, ii) adhesive layer, and iii) a combination of selftapping screws and adhesive layer. Research at UNITN targeted the use of “dry” connections for timber-to-timber composites, specifically reversible reinforcement techniques aimed at increasing the load-bearing capacity and the bending stiffness of existing timber floors. At UniMinho, double span continuous glulam slabs were strengthened with fibre-reinforced-polymers. All three examples demonstrate the improved structural performance of timber elements after reinforcing them., The research on RDJ was funded by BFH and supported by the staff at the BFH " tech-park" Huesser Holzbau AG and ArundaR. The research at UNITN was carried out by the Timber Research Group (in particular by M. Piazza, R. Tomasi, I. Giongo) within the framework of the RELUIS Project 2011-2013, which is financed by the Italian Emergency Management Agency (Dipartimento della Protezione Civile) and supported by Rothoblaas srl.

The use of analysis techniques for industrial controller’s analysis, such as Simulation and Formal Verification, is sometimes complex on industrial context. This complexity is due to the fact that such techniques require sometimes big investment in highly qualified human resources that have sufficient theoretical knowledge in those domains. This paper aims, mainly, to show that it is possible to improve the implementation and industrial using of such techniques, by facilitating their application. As any mechatronic system needs to be modeled by using CAD models, these models could be used, in a systematic way, by these companies in order to increase the use of such techniques for the analysis of industrial controllers. For this purpose, it is discussed, in the paper, the best way to systematize these procedures, and this paper describes, only, the first step of a complex process and promotes a discussion of the main difficulties that can be found and a possibility for handle those difficulties is presented. A case study is presented in order to illustrate how to obtain a plant model for formal verification purposes from an original 3D CAD model.

In this paper is analyzed the behavior of parameters that characterize the process of a dynamic crack growth along the interface between the two orthotropic materials. The emphasis is placed on the application of the fracture mechanics concept for the interfacial crack that propagates dynamically, at high speed. In this work is considered the behavior of the oscillation index, the traction resolution factor and the energy factor depending on the crack tip speed and the stifnesses ratio. The oscillatory index increases with the crack tip speed and tends to infinity when the crack speed approaches the Rayleigh wave speed of the less stiff of the two materials. The traction resolution factor depends strongly on the crack speed but weakly on the stiffness ratio. The behavior of the energy factor is completely different from the behavior of the traction resolution factor. Results provided in this paper can be used as a guide for micromechanical modeling of materials.

This paper discusses the problems of identifying external loads of multibucket machines for mechanization. External loads are dominantly dynamic with distinguished stochasticity in certain cases. The paper presents the procedures for determining external loads caused by resistance-to-excavation (for bucket wheel excavators) or grabbing soil (for bridge-type coal stacker-reclaimers), as well as a short description of the model upon which is based and defined the response of the stacker-reclaimer to the external changeable load. It points to the significance of the problem of identifying the external load, as well as to the potentially very detrimental and dangerous consequences of eventual shortcomings during solving the mentioned problem.

The paper is related to the San Torcato Church, in Guimarães, Portugal. At the moment, the church has significant structural problems due to soil settlements. Cracks can be observed on the main and the lateral façades, the bell-towers are leaning, and the arches in the nave exhibit a failure mechanism with cracks and vertical deformations. Non-stabilized phenomena are present in the structure. To stabilize the damage, a structural intervention is planned to occur soon and the church is already monitored to follow the intervention. The paper clearly presents the problem with emphasis to the dynamic analysis carried out before the structural strengthening, namely: the experimental tests with output-only techniques for frequencies, damping and mode shapes estimation, FE model updating analysis and dynamic monitoring

Since earthquakes such as Northbridge (1994) and Kobe (1995) gave the impetuous for the development of performance-based design methods, engineers have been strenuously working to the improvement of the seismic behaviour of structures; in fact, high ductility frames, as well as damping and isolation systems, are nowadays common practice in seismic prone areas. Heritage buildings constitute an odd case: many historic centres are still considerably affected by seismic events (L’Aquila, 2009) due to the lack of a methodical retrofit and this, where applied, is still largely based on the increase of stiffness and capacity, without the due care for precious finishings. In order to address the lack of specific passive systems for heritage buildings, the authors have developed two typologies of dissipative devices that can be integrated in traditional steel anchors and installed within the masonry at the joints of perpendicular walls, where out-of-plane mechanisms are likely to form due to poor quality connections. Both prototypes, one based on the plasticity of steel, the other relying on friction, were tested as isolated elements in pseudo-static regime for proofing and fine tuning, and in a dynamic range typical of the seismic frequency content to validate the stability of dissipative loops. The paper focuses on pull-out tests aimed to analyse the behaviour of the hysteretic prototype in respect to traditional steel anchors in masonry panels with low shear capacity. Finite Element (FE) models were also developed and calibrated applying the data from tests. Experimental and computational results are discussed in the following; the need for further theoretical work concludes the paper.

The paper presents a series of experimental researches performed using the design of experiments method RSD (Response Surface Design) for modeling and optimizing the welding process of PE 100 pipelines, used in natural gas distribution. In this sense, the aim was to analyze the influence of controllable factors such as pressure, temperature and time on the objective functions, aiming to obtain certain characteristics of the welded joint. By modeling the welding process, based on the results obtained, an optimal welding procedure was established and validated to meet the conditions imposed on the objective functions.

Developing a non-destructive method which delivers fast, accurate and non-invasive results regarding the concrete compressive strength, is an important issue, currently investigated by many researchers all over the world. Different methodologies, like using the simple non-destructive testing (NDT) or the fusion of different techniques approach, were taken into consideration in order to find the optimal, most suitable method. The purpose of this paper is to present a new approach in this direction. The methodology consists in predicting the concrete compressive strength through ultrasonic testing, for non-destructive determination of the dynamic and static moduli of elasticity. One important, basic assumption of the proposed methodology considers values provided by technical literature for concrete dynamic Poisson’s coefficient. The air-dry density was experimentally determined on concrete cores. The dynamic modulus of elasticity was also experimentally determined by using the ultrasonic pulse velocity (UPV) method on concrete cores. Further on, the static modulus of elasticity and the concrete compressive strength can be mathematically calculated, by using the previously mentioned parameters. The experimental procedures were performed on concrete specimens, namely concrete cores extracted from the raft foundation of a multistorey building; initially they were subjected to the specific NDT, namely ultrasonic testing, and the validation of the results and the proposed methodology derives from the destructive testing of the specimens. The destructive testing is generally recognized as the most trustable method. The precision of the proposed method, established with respect to the destructive testing, revealed a high level of confidence, exceeding 90% (as mean value). It was noticed that even the cores with compressive strength outside of mean range interval (minimum and maximum values) presented high rate of precision, not influencing the overall result. The high rate of accuracy makes this method a suitable research background for further investigations, in order to establish a reliable NDT methodology which could substitute the very invasive and less convenient, destructive method.

Lattice structures can be highly complex imitating natural cellular materials. By the wide adoption of additive manufacturing technologies, lattice structures are a popular design element with many advantages for lightweight and highly functional parts. A detailed examination and an intense inspection of this type of new design element and this new production method is necessary to enable a broad industrialization. In this study we demonstrate how to use x-ray based industrial CT to measure lattice structures in additive manufacturing. This paper shows certain challenges and approaches for metrology on lattice structures. The results show significant deviations between designed and built parts, highlighting the need for quantification and non-destructive inspection.

In this paper, heat affected zone characteristics of DP1000 steels was investigated during diode laser beam welding (LBW). A butt-welded joint of specimen in dimension of 300 x 150 mm each (according to EN15614-11:2002) with 1 mm thickness is used for the experimental purpose. The welding thermal cycle and the cooling circumstances in the HAZ was determined by real experiment and the physical simulation. A Gleeble 3500 thermo-physical simulator was used to physically simulate the coarse grain heat affected zone (CGHAZ) on the base material specimens by the utilization of the thermal cycles for t8/5 =2.5 s. The results of the physical simulation were validated by real welding experiments. The properties of the simulated and the real HAZ was examined by optical microscopic, scanning electron microscope and hardness tests.

This paper discusses the potentials of different wood constructions for the renovation and extension of existing buildings for sustainable urban renewal. The renovation and extension of existing buildings with wood constructions can contribute significantly to sustainable urban redevelopment. The renovation of building envelopes, such as façades and roofs, with highly insulated wooden components, can reduce the transmission heat losses and related heating energy demand of existing buildings significantly. The extension of existing buildings contributes to the redensification of urban areas and can create synergies with the improvement of existing buildings’ performances. The manifold advantages of specific wooden constructions can be related to different aspects, such as construction type and material properties, building execution, design, logistic and sustainability. The results of this research discuss the architectural design and planning relevant properties of specific timber construction types, such as wood frame, cross-laminated timber (CLT), massive timber, and hybrid timber-concrete, considering the properties of different soft (such as spruce) and hard (such as beech) construction timber species. Timber constructions are compared with conventional massive constructions out of concrete and steel. The results confirm the significant advantages of timber constructions regarding all aspects.

Advancements in computational tools are offering designers the possibility to change their relationship with materials and establishing new synergies between matter, form and behaviour. This work explores this paradigm by introducing the use of auxetic metamaterials, specifically engineered to obtain properties beyond those found in nature, to generate structures with adaptive curvature obtained from planar construction elements. It is discussed how through programming an initial geometry with the strategic negotiation of several geometrical parameters it is possible to control finely the structural and morphological features of a structure. The paper presents approach, tools and methods for designing auxetics for large scale applications, and use them to create heterogeneous active-bending structures.

The paper presents methods for testing the composite materials using two types of fiber-optic sensors as well as a method for using radiation of the vertical-cavity emitting laser radiation (VCSEL) for checking the material deformation and its performances. The deformation checking sensor is a fiber Bragg grating (FBG) with a spectrum width of 50 pm, which is interrogated by the VCSEL. A new algorithm for modulating the laser diode current is proposed for the FBG interrogation providing a dynamic range of at least 3 nm. A new interrogation method of impulse Fabry-Perot interferometer was proposed. The interrogation method was applied for a fiber-optic acoustic emission sensor manufacturing. The sensor was experimentally investigated by the impact of a 6 mm diameter steel ball and compared to a reference piezoelectric acoustic emission transducer.

In the paper are presented some preliminary results regarding the possibilities of using of the friction stir welding process (FSW) and FSW assisted with TIG (FSW – TIG) welding for joining of the electrical components in the automotive industry. Couples of dissimilar materials approached in experiments were Aluminium EN AW 1200 and Copper Cu99, with thicknesses in conformity with real cases in the production process. The results obtained for butt welding an overlap welding of different thicknesses of materials (aluminium thickness s1 = 2mm and copper thickness s2 = 5mm) are presented. There are some general conclusions regarding the possibilities of joining the two materials under the specified conditions.

The paper is described experiment that is measured the level of vibration at a football stadium in Prague's Eden. The vibrations were monitored in the stadium, where is located the most active fans of the home team SK Slavia Praha. Measurement is based on similar experiments, which realized at a football stadium in Letná in Prague and hockey stadium in Pilsen in 2013 and 2015. The main part of the article is nearing the level of vibration grandstand (acceleration and excitation frequency) in characteristic events during the match.

Numerical analysis of masonry structures is a complex task requiring deep knowledges about the problematics. This paper deals with concentrically compressed brick masonry column reinforced by fiber reinforced polymer (FRP) wrapping. The experimental research across the world has proved that FRP external sheets are an efficient tool for stabilization or strengthening of masonry structures. A combination of several types of column’s failure were observed during the experimental testing – failure in masonry, rupture of FRP sheet or failure at interface between reinforcement and masonry support. The rupture of sheet occurs close to sharp corners under the assumption of sheets’ perfect overlap. The rounded corners result in an enlargement of the FRP-masonry contact and reduction of the stress concentration. The increasing of an effective area causes a greater influence of FRP wrapping. For all 3D simulations the commercial software package ABAQUS was used and the obtained results are discussed.

This paper is focused on testing in mode II. In this article there is presented the double-edge notched specimen based on the theory of the infinite plate to determine the critical factor KII. There are three approaches to this testing here. Firstly, the real test documented by photos and measured data to determine the value of the critical stress intensity was carried out. Secondly, the real test evaluated by the digital image correlation and finally the numerical model in Adina was made. The success of the testing was lower than has been expected (only 24 %). All three prescriptions were used for all 55 specimens. The highest value of KII is reached with the prescription without fly ash.

The paper addresses the development of advanced welding technologies with two and three solid wires for joining of HSLA API-5l X70 (High-strength low-alloy) steel plates with thickness of 19.1 mm. The experiments were performed using a multi-wire Submerged Arc Welding (SAW) system that was developed for welding of steels with solid, tubular and cold wires, in different combinations. The main goal of the research was to assess the mechanical performances of the welded joints achieved by multi-wire SAW technology and then to compare them with the single wire variant, as reference system. The welded samples were firstly subjected to NDT control by examinations with liquid penetrant, magnetic particle, ultrasonic and gamma radiation, with the aim of detecting the specimens with flaws and afterwards to reconsider and redesign the corresponding Welding Procedure Specifications (WPS). The defect-free welded samples were subjected to tensile, Charpy V-notch impact and bending testing in order to analyse and report the mechanical behaviour of API-5l X70 steel during multi-wire SAW process. The experimental results were processed and comparatively discussed. The challenge of the investigation was to find the appropriate welding technology which responds simultaneously to the criteria of quality and productivity. Further research on metallurgical behaviour of the base material will be developed, in order to conclude the complete image of the SAW process effects and to understand how the multi-wire technologies affect the mechanical and metallurgical characteristics of the API-5L X70 steel used in pipelines fabrication.

The paper presents some results on the effect of the metal electrode deposition on the electrical performance of amorphous polymthylmetacrylate (PMMA) thin films, measured in a MIM structure consisting of metal (Al)-insulator (PMMA)-metal (Ta). Aluminium (Al) electrode was deposited by physical vapor deposition method (PVD) on the top of PMMA film with the deposition rate of 5 and 10Å/s. The effect of aluminium deposition rate and post deposition annealing temperature on the morphology of the interface between Al electrode (100 or 300 nm thick) and PMMA thin film (40 or 70 nm thick) has been investigated by cross-section scanning electron microscopy (SEM). Based on SEM data, I-V characteristic measurements and dielectric constant values of insulating films, the deposition parameters of Al top-electrode was optimised. Our results showed that when the deposition of the Al electrode take place at a rate of 10 Å/s, no inter-diffusion or interfacial reaction at the interface between Al electrode and PMMA films were observed and the best delectric parameters of PMMA thin film were measured, which led to the best dielectric performance of PMMA layer in TFT configuration.

In this paper the influence cell honeycomb geometry on the mechanical behaviour of a composite sandwich plate is analyzed. Three cell geometries (circular, hexagonal and square) are static analysed so that to select the best type of honeycomb that will be used in the manufacturing the sandwich plate core. The main aim is to develop approach models of equivalent orthotropic materials to replace the real model of honeycomb core with their properties so that to quickly calculate the sandwich plate made out of composite when is used a finite element analysis code. Geometry and material properties of the honeycomb are delivered by the material provider. Comparative analysis, by using Finite element analysis is performed for all geometries, in the same boundary conditions. Since in the impact loading of the composite sandwich plate the core is mainly loaded to compression, comparative study of the three cell geometries honeycomb was performed for this type of compressive loading. Since the cell is the basic element of the honeycomb core, the calculus is performed for one unit volume of sandwich, concerning also the part of skins.

In this paper a parametric static and torsion analysis on a catamaran ship structure made out of composites materials is performed. The best solution for material selection is based on specific criteria for certain analysis. For dynamic analysis, the main criteria is to obtain the structure natural frequencies in a range, far from the resonance frequencies produced by the ship propulsion installation, wave loads etc. For static analysis the comparative criteria is to obtain the lowest weight of structure for the same strength. Also, buckling item is other criteria for comparative analysis. The comparative analysis is performed between rule based scantling structure and a FEM based structure for a composite material twin hull deck, in order to reduce the total hull weight. Material used for ship deck structure of the analyzed ship is e-glass polyester.

This paper presents the experiment-based mathematical modelling of fluidized bed carbonitriding process for 1C 25 steel meant to optimize this type of thermochemical processing.Based on experimental results, the mathematical model was developed, which is a second order equation with three unknown terms (parameters): temperature, depth of carbonitrided layer, the percentage of ammonia.The mathematical model allowed the simulation of the fluidized layer carbonitriding process according to its parameters and the thermal energy optimization for obtaining HV hardness values in the range 300-400 MPa.Using the software package Matlab a graphical interface was done, through which all the combinations of technological parameters of the carbonitriding process are determined, leading to obtaining values of microhardness between 300 and 400 MPa, as well as the amount of energy consumed for each variant. The variant consuming the lowest energy is considered optimal.

This paper presents the FEM approach of fatigue life estimation of a layered composite plate having a central elliptical cut-out subjected to time variation loads. Some properties and material data, such as data used for the S-N curve / Wöhler curve of the material, represented in cyclic stress versus number of cycles to failure coordinates, which is required for starting the fatigue analysis, were taken from the OPTIMAT database.The plate analysis was parameterized and modeled with the Shell281 element type. This type of element can be used in a triangular form more efficiently than other types of shell elements available in version 15 of ASYS APDL.Initially, the static analysis was performed to identify the node with the maximum principal stress (hot spots). This node was used for performing the fatigue analysis. The fatigue parameter to estimate fatigue life is cumulative fatigue usage factor. This factor is obtained by adding together all individual usage factors calculated for each variable load that is applied to the analyzed plate. The fatigue usage factor is used to estimate the percentage of life that is consumed after applying the fatigue loads. The value of the usage factor is in the range from 0 to 1.

Carbon fiber reinforced silicon carbide composite (Cf/SiC) is the new high temperature ceramic composite developed in recent years, widely used in the aviation, aerospace and other high-tech fields. In this paper, a variety of joining methods of Cf/SiC composite to metallic materials, including active filler brazing, solid phase diffusion welding, liquid infiltration joining, as well as chemical vapor deposition of niobium transition joining technology were introduced. At the same time, the features and disadvantages of each technique were evaluated. This review is intended to provide a comprehensive guide to the design and application of Cf/SiC composite joining to metals.

The use crowd of escalators involves a wide range of people. Therefore, the safety research of escalator is concerned and should be pay more attention to continuously. In the present paper, the multiple material damage modes of escalator drive chain were analyzed. The material damage modes mainly contain the micro cracking, the wear damage and the decarburization defect. The tensile tests and friction&wear experiments were performed to investigate the influence of the material damage modes on the performance of the escalator drive chains in service. The tensile properties of the new drive chains without material damages were superior to those with decarburization defect and wear damage. The friction&wear experimental results indicated that the decarburization defects reduced the wear resistance of the escalator drive chain. The research results implied that the strict quality control and improved maintenance of the escalator drive chain was meaningful for the escalator using security.

Ceramsite cellular concrete (CCC for short) is a kind of lightweight aggregate concrete. In this paper, the selection of materials and design of mix proportion have been discussed, and basic property tests has been done. The compressive strength was proved up to the National Standards of P. R. GB50003-2001(code for design of masonry structures), furthermore, elastic modulus and Poisson's ratio were also introduced. Questions remain regarding the quality control of the product, and further work is needed to resolve this contradiction.

Sawing with bandsaws is a fast and efficient process for cutting semi-finished parts out of bar stock in the metalworking industry. However, the produced surface quality on the workpiece is low due to the unguided length of the saw blade during the engagement in the workpiece. The kinematic correlation between the thin, unstable structure of the saw blade, only pre-stressed in the cutting direction, and the distance of the two saw blade guides according to the workpiece dimensions leads to an indefinite behaviour of the saw blade in the kerf. Apart from the surface quality, this cutting behaviour also causes a great wear of the tool. With increasing wear of the tool, the process becomes more and more unstable and the cutting loss increases. For an optimization of the sawing process, the influences on the stability of the process are investigated by experiment on a test bandsaw equipped with extensive measurement equipment. This paper examines how the saw blade tension influences the stability of sawing processes subject to tool wear. For this purpose, the saw blade tension is varied in a wide range and the stability of the process is assessed. The results obtained show a great influence of the saw blade tension on the sawing process and form the basis for developing a stand-alone stability control system to automatically adjust the sawing parameters.

In this paper a high loaded hot forging die, which is oriented towards an industrial forging process, is developed with assistance of finite element analysis. In serial hot forging tests and process accompanying analysis methods the designed die geometry gets investigated concerning occurring wear mechanisms. Within the investigation it could be shown, that calculated results of the wear condition are corresponding to the experiments. Abrasion, plastic deformation and mechanical cracking could be detected. The variety of occurring wear mechanisms on the designed die allows a promising approach of further investigations on the valuation of different wear reducing strategies.

The predicted results of production simulations often differ considerably from those of the practice. Among other things, reasons for that can be found in the inadequate consideration of the socio-technical system of the real manufacturing. The paper addresses this problem and shows how even complex manufacturing principles such as semi-autonomous groups can be simulated with the help of agent systems using an adapted Belief-Desire-Intention (BDI) architecture concept.

Machine vision systems need to cope with harsh environmental conditions, when used for guiding robots. To increase the reliability of these systems, they are either shielded from their environment or highly advanced, using sophisticated mathematical algorithms. In this paper the effects of external illumination on machine vision systems are investigated. For this the pose and the brightness of the external illumination and the internal illumination of the camera and its exposure time are varied. In a next step the correlation between the parameters of the external illumination and reliability of the machine vision system is analysed. Finally requirements are derived for further development of machine vision systems.

Generally, hard finishing is the final step in manufacturing cylindrical gears. The most established processes for hard finishing are continuous generation grinding and discontinuous profile grinding [1]. Despite the wide industrial application of the continuous generation grinding process, only few scientific investigations exist. One possible reason for this are the complex contact conditions between tool and gear flank. Modelling the complex contact conditions between grinding worm and gear to calculate cutting forces, characteristic values as well as micro- and macroscopic gear geometry are the topics of this paper. The approaches are introduced and results for validation are presented and discussed.

Startups can substantially contribute to the industrial development in the early and newly industrialized countries by transforming technological inventions into products and services. By means of the market dynamics of cooperation and competition in global value creation and knowledge networks, new products and services can conduce to a global industrial development. Hence, in pursuance of an efficient and effective startup development, this paper will present a new methodology for the integrated development of the product and of the business model for a hardware startup. Hardware startups address the development of innovative tangible products. The hardware product itself may consist of mechanical, electronical, and software components. The methodology is based on a micro cycle for the problem-solving procedure on the level of single process steps as well as on a macro cycle as procedure for the overall integrated development of the startup. For each phase of the macro cycle, specific modelling methods for the product and business model are proposed. Finally, a proof of concept on the basis of a student startup, which is developing a micro wind turbine, will be presented.

Due to the limitations of other processes in joining different types of material, mechanical joining methods can be alternatively used. Joining by upset bulging can be employed for joining tubes with other structures such as sheets, plates, tubes or profiles as well as for joining different materials. In spite of successful industrial applications of this joining process, material damage is still a challenge. This damage affects the resistance of the created joint to service loads. Thus, in this paper, a local heating is studied, which aims at avoiding pre-damage or failure of the joint. A parametric FE model is developed to analyse the influence of local heating on the bulging process. It is found that the process window set by the bulge length suitable for joining is widened, but only to a minor extent. The marginal influence of local heating on the bulge geometry allows designing the process in the same way as room temperature processes. Metallographic investigations confirm the damage-free bulging of tubes by forming at elevated temperatures. Another important result is that tubes can be equipped with predefined bulge zones by local heating zones to 700 °C for 15 seconds for example. This enables bulging of tubes during joining by applying an axial load only, without using tools to define the location of the bulge or its length, thus enabling joining operations with limited access.

Today’s manufacturing companies are exposed to the challenge of fulfilling constantly growing and heterogeneous customer expectations. Simultaneously, the demand for delivering the highest quality in shortest time increases strongly. One way to handle these requirements is the highly iterative product development approach. By distributing development processes in short and iterative sub-processes, this method generates customer oriented and marketable products. However, most producing companies fail by trying to adopt the short-cycled concept without considering the suitability of these methods for the respective project. According to that fact, this paper aims at the presentation of a methodology which shows how to evaluate and select highly iterative product development methods for individual development scopes. A first application of this methodology indicated affirmative results regarding to the practicability within a startup enterprise. Still, there is need for further research, especially in the field of implementation.

Today's sandwich structures and materials offer a high potential for lightweight design and are being used in various industrial applications. However, the material and manufacturing costs for structural sandwich structures in aerospace and automotive industry are comparatively high. Furthermore the production of lightweight and functional composite-sandwich components is usually characterised by long manufacturing lead times and a high level on manual workload. In this context the production of lightweight, functional and geometric complex sandwich structures consisting of SMC layers and closed cell rigid foams as core material in a single-step compressing moulding process is very promising. By using such a process new design approaches, a high level of functional integration as well as excellent cost, material and resource efficiencies can be realised. This paper deals with the new manufacturing approach, first experimental investigations on the mechanical properties and the estimated potentials for using these high-efficient, lightweight sandwich structures in aviation and automotive industry.

The production of irregularly shaped deep drawing parts with high quality requirements, which are common in today’s automotive body shell production, consistently challenge production processes. This challenge results from the high design requirements and automotive lightweight design, and hence the necessary use of high strength steels. Metal forming technology deals with these challenges using highly sophisticated methods to control the material flow. Several control loop methods have existed already in order to control the material flow in deep drawing processes, but only methods with a control intervention between two strokes. However, this kind of control method merely allows control intervention on measurements on the previous part or on measurements of material properties before the actual process. The method developed at the Institute for Metal Forming Technology in Stuttgart makes a control intervention possible during the deep drawing stroke. The used reference variable is the part wall stress and the control variable is the blankholder force, which is manipulated by using the segment elastic blankholder as an actuator. In this paper the experimental setup, the control methods, and the control loop itself will be presented. Furthermore, the developments of the new method will be described.

The chip formation mechanisms during grinding are not yet fully understood. The abrupt interruption of the grinding process with a quick stop device is a suitable method to analyze the chip formation mechanisms during grinding. However, there is no device available that enables a reproducible interruption at cutting speeds above vc = 5 m/s. Therefore a new method for the interruption of face grinding processes in order to analyze the chip formation mechanisms is presented in this paper. A quick stop device is designed and constructed based on the advantages and disadvantages of former approaches of other researchers. Grinding experiments with different rotational speeds confirm the potential of this new device. Interruptions of the grinding process at cutting speeds of vc = 5 m/s, 15 m/s, 25 m/s and 35 m/s are successfully accomplished. A detailed analysis of the contact zone with the help of SEM pictures impressively shows the interaction of hundreds of cutting edges along the contact zone.

Lithium-ion batteries are a key technology for energy storage not only in consumer electronics but also in e-mobility and stationary applications. However, in order to guarantee the success of lithium-ion batteries in the long term, improvements related to performance, lifetime and production costs need to be made. Mastery of the highly interlinked process chain in lithium-ion battery manufacturing is a challenge and often acquired on the basis of experience. This paper illustrates the complexity of this process chain with a special focus on the roll-to-roll manufacturing of electrodes and discusses the application of a quality management system in lithium-ion battery production.

In sheet metal forming, the fixation of tools in presses has not been considered to be variable for process optimization yet. Every clamping point fixes the tool. Tool areas without a fixation point have a vertical degree of freedom, respectively. Against this background, it seems to be evident that the kind of tool fixation can influence its static and dynamic beahviour. In shear cutting processes, tool vibration is an important phenomenon, as it affects tool wear on the one hand and influences part quality on the other hand. In this paper, a methodology for influencing the tool vibration by specific setups of the clamping situation is introduced.

The increasing customisation of products, which leads to higher numbers of product variants with smaller lot sizes, requires a high flexibility of manufacturing systems. These systems are subject to dynamic influences and need increasing effort for the generation of the production schedules and for the control of the processes. This paper presents an approach that addresses these challenges. First, scheduling is done by coupling an optimisation heuristic with a simulation model to handle complex and stochastic manufacturing systems. Second, the simulation model is continuously adapted by real-time data from the shop floor. If, e.g., a machine breakdown or a rush order appears, the simulation model and consequently the scheduling model is updated and the optimisation heuristic adjusts an existing schedule or generates a new one. This approach uses real-time data provided by future cyber-physical systems to integrate scheduling and control and to manage the dynamics of highly flexible manufacturing systems.

Seamless rings are applied in several industrial sectors and are mainly produced by radial-axial ring rolling. Ring climbing is one of the most occurring process errors leading to a distortion of the ring’s cross section. This paper presents the determination of the influencing factors and their impact and correlations on the process error of ring climbing via Design of Experiment. The highest impact on the climbing height of a ring has the adjustment of the rolling table and the guide rolls. Relatively low but still noticeable is the influence of the process parameters of the rings displacement and the unequal axial rolling speeds. With this knowledge it will be possible to develop, test and implement a rolling strategy that may reduce or avoid ring climbing successfully.

Nowadays, the finite element method is still the first choice of researchers in metal extrusion analysis. However, recent published papers have also supported that metal plastic flow can be modelled by the flow formulation, employing the finite volume method. In this work, the numerical scheme presented by Martins et al. [16] based on finite volume method together with the explicit MacCormack numerical method, was used to analyse aluminum axisymmetric direct extrusion in a 90° die. A structured, fixed and collocated mesh and numerical convergence based on the SIMPLE method were employed to attain pressure-velocity coupling. The main goal of present numerical scheme was to obtain the axial and radial velocities and pressure distributions. From these results, it was possible to obtain and identify the dead zone inside the billet deformation region in direct extrusion of aluminum in a 90° die. The field variables results shown in present work had good agreement when compared with those from literature.