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In the present paper, the effects of cake thickness and time on the efficiency of brown stock washer of the paper mill are studied by using mathematical model of pulp washing for the species of sodium and lignin ions. The mechanism of the diffusion‐ dispersion washing of the bed of the pulp fibers is mathematically modeled by the basic material balance and adsorption isotherm is used to describe the equilibrium between the concentration of the solute in the liquor and concentration of the solute on the fibers. To study the parametric effect, numerical solutions of the axial domain of the system governed by partial differential equations (transport and isotherm equations) for different boundary conditions are obtained by the “pdepe” solver in MATLAB source code. The effects of both the parameters are shown by three dimensional graphical representation as well as concentration profiles.

In response to published reports about the decline in funding for space nuclear power, the Board of Directors of the American Institute of Aeronautics and Astronautics (AIAA) approved a position paper in March 1995 that recommends (1) development and support of an integrated space nuclear power program by DOE, NASA and DoD; (2) Congressional support for the program; (3) advocacy of the program by government and industry leaders; and (4) continuation of cooperation between the U.S. and other countries to advance nuclear power source technology and to promote safety. This position paper has been distributed to various people having oversight of the U.S. space nuclear power program.

Prior work has established the existence of a color-performance relationship in achievement contexts and has demonstrated its presence in some undergraduate course examinations. This study examines the manifestation of such a relationship in an introductory, 430-student, calculus-based electricity and magnetism course during which the paper color used in examinations was varied. In this report, we analyze three separate exams and differentiate between students’ multiple choice, written response, conceptual, and computational performances. Also considered are factors such as the time students require to complete exams and their confidence levels prior to and immediately following assessment. Performance in all categories appears to be independent of paper color.

In this paper we present an application of two Computational Intelligence Algorithms, namely Particle Swarm Optimization (PSO) Algorithm and Differential Evolution (DE) for finding and optimal solution to two optimization problems that occur in a paper industry. The first problem deals with the economic optimization of a hypothetical but realistic Kraft pulping process and in the second problem we have considered the optimization of Boiler load allocation problem. Both the problems form an integral part of paper making process. The simulation results show the efficiency and time effectiveness of DE and PSO.

The work concerns the parameter estimation in the context of the mechanistic modelling of a pulp digester. The problem is cast as a box bounded nonlinear global optimization problem in order to minimize the mismatch between the model outputs with the experimental data observed at a real pulp and paper plant. MCSFilter and Simulated Annealing global optimization methods were used to solve the optimization problem. While the former took longer to converge to the global minimum, the latter terminated faster at a significantly higher value of the objective function and, thus, failed to find the global solution.The work concerns the parameter estimation in the context of the mechanistic modelling of a pulp digester. The problem is cast as a box bounded nonlinear global optimization problem in order to minimize the mismatch between the model outputs with the experimental data observed at a real pulp and paper plant. MCSFilter and Simulated Annealing global optimization methods were used to solve the optimization problem. While the former took longer to converge to the global minimum, the latter terminated faster at a significantly higher value of the objective function and, thus, failed to find the global solution.

Papers produced from oil palm empty fruit bunches (EFB) via Alkaline Peroxide Pulping (APP) was preceded by three main steps; dewaxing of EFB, alkaline peroxide (AP) impregnation into EFB and refining of biomass to generate pulp. The experiment was carried by varying chemical level and number of impregnation stages. For 2:2.5% AP level, two-stage impregnation improved hand sheets tear index by 45%, 164% boost in tensile index, 26% enhancement in zero span index and more than 5% in burst index. By applying 8:10% AP level, significant improvements were gained at the third and fourth stages of AP impregnation. Although there was no significant change in hand sheet strength with multiple impregnation for 4:5% AP level, improvement in brightness of hand sheets was apparent, analogous to the effect of increasing AP level. The found paper properties development show that alkaline peroxide pulping of EFB could be adapted to various targeted properties by adjustment of AP level and impregnation stages.

The pulp extracted from the alkaline peroxide pulping (APP) of EFB was beaten from 500 revolutions to 10000 revolutions using PFI mill to investigate the morphological changes undergone by the pulp and the resultant effect on paper sheet properties. As a result of beating, pulp elements were observed as intensely fibrillated, reducing the amounts of fibre bundles and thus, reducing interruption in the inter-fiber bonding. To a defined extent, beating was also seen as unwinding the structure of vessel element to a single strand of loose spiral body. These fibrillated vessel elements of APP pulp from EFB, plus the fines element germinating from further segmentation of the vessels, were the factors contributing to the overall strength improvement of the produced EFB pulp network. The applied increment in beating revolution had apparently widened the known broad spectrum quality of APP pulp from EFB. This demonstrates EFB potential for application in specialty paper production.

Biomass seems to have a great potential as a source of renewable energy compared with other sources. The use of biomass as a source of energy could help to reduce the wastes and also to minimize the dependency on non-renewable energy, hence minimize environmental degradation. Among other types of biomass, oil palm wastes are the major contribution for energy production in Malaysia since Malaysia is one of the primary palm oil producers in the world. Currently, Malaysia’s plantation area covers around 5 million hectares. In the oil palm mill, only 10% palm oil is produced and the other 90% is in the form of wastes such as empty fruit bunches (EFB), oil palm shells (OPS), oil palm fibre (OPFb) and palm oil mill effluent (POME). If these wastes are being used as a source of renewable energy, it is believed that it will help to increase the country’s economy. Recently, the most potential and efficient thermal energy conversion technology is pyrolysis process. The objective of this paper is to review the current research on pyrolysis of oil palm wastes in Malaysia. The scope of this paper is to discuss on the types of pyrolysis process and its production. At present, most of the research conducted in this country is on EFB and OPS by fast, slow and microwave-assisted pyrolysis processes for fuel applications.

Development of the desired pulp-based products eco-properties are governed by factors like choice and suitability of raw material, the design and operation of pulping process and choice of additives. Fines recovered during refining discharge of an alkaline peroxide pulping system were collected based on their retention on varying mesh-sizes screens. Analysis shows that 12% of the 400-mesh fines added to the web enhances paper tensile strength by 100%. This defines the usefulness of fibrillar particles whose cell wall collapsibility increases the web density by increasing bonding ability and thus, strength of pulp-based products such as paper. The study acknowledges fines functioning as natural filler in pulp network and collection of fines from the refining discharge was found to reduce 70% turbidity and this improvement will help reduce the costs pertinent to generation of whitewater from the pulping system.

EFB (empty fruit bunch) was subjected to alkaline peroxide pulping for generation of fibrous mass as raw material for the making of pulp-based products. During refining, co-produced fines were collected by fractionation on square-mesh screens of 200-, 250-, 300- and 400- mesh sizes, placed at the refining discharge by order of increasing mesh. Each set of the produced paper was incorporated with 12% fines for microscopic analysis. It appears that sheared vessel elements and fibrils were predominant and they make up the mass rendering collapsibility of cell wall for good product formation. The study acknowledged the form of fines functioning as natural filler in pulp network and worthy of utilization for reduction of total suspended solid.

In our present work, we describe a simple method for uniform coating of Graphite oxide (GO) onto flexible polyurethane (PU) foams. These PU foams loaded with GO were made electrically conducting by converting insulating GO to conducting graphene by chemical reduction process without damaging the foam properties. These PU foams loaded with graphene were characterized by SEM and TGA. The morphology, thermal properties and pressure dependent electrical conductivity of these foams was studied. The electric current increased by five orders of magnitude due to applied pressure.

Composite materials were modified in order to increase their wear resistance when in contact with raw-cotton. It is found that the friction pairs increases their efficiency and durability to 2.0-2.2 times.

This work presents a preliminary study on the carbon isotope signature and trace metal content investigated on the soil-plant-fruit pulp chain. The samples were collected from two Transylvanian areas namely Alba and Salaj. The average value of the δ13C at the soil surface was around δ13C ≈ −27%o and important differences of the δ13C values between the two studied areas were not observed. Meanwhile, differences between fruit pulp of grape juice and the pulp of pear juice relived a difference of about 1.5%o for δ13C values.

The present study is focused on development of environmentally friendly intumescent/char forming coatings for wood and polymeric materials. For this purpose we have developed the method of oxidation of raw materials: polysaccharides, seeds and lignin by oxygen in the presence of catalyst. The main products of oxidation of such substrates are the salts of polyoxy- and polyphenoxy acids. The efficiency of fireproofing action of novel surface protecting intumescent coating for wood and polymeric materials based on modified renewable raw materials was studied. Flammability tests of wood and polymers samples treated by oxidized raw materials confirm their high-performance fire protection.

The waste fly ash and shell fish are added to base material of cement (clinker, gypsum, trash and lime stone), for environmental reason. The ratio fly ash and shell fish was varied respectively 375:125; 250:250; 125:375, in grams weight for 2500 grams of total material. The chemical composition of raw material was determined by using x-rays fluorescence (XRF). Physical properties of sample match with Standar Nasional Indonesia (SNI). The physical properties of the best sample is made from composition of fly ash and shell fish as a substitution material on cement was 10% in weight, with ratio 250:250 in grams weight.

The quantity of polymetric materials in the form of plastics, synthetic fibers and rubber derived from petrochemicals produced in the U.S. in 1974 amounted to about 18 million tons. This is modest compared to the approximately 50 million tons of wood pulp consisting essentially of cellulose produced, and in fact all our polymer needs could be met by conversion of the cellulose and lignin of wood. Cellulose can be hydrolyzed to glucose which can then be fermented to ethanol. The production of ethanol and its dehydration to ethylene, the most important petrochemical building block, proceed in high yield. However, the hydrolysis of cellulose whether by enzymes or by acid gives poor yields of glucose. Quantitative conversion of cellulose to glucose would improve the economics markedly. The high crystalline structure of cellulose limits access of the hydrolyzing agents except under conditions of acidity and temperature under which the glucose formed is destroyed. Futhermore the presence lignin prevents access of hydrolytic enzymes to the cellulose. Disruption of the cellulose crystal lattice by radiation or swelling agents has provided increased accessibility and higher glucose yields. Increasing the surface area of exposed cellulose by ball milling lignified cellulose has allowed enhanced enzymatic hydrolysis. However, more efficient techniques for removing these barriers to cellulose hydrolysis are needed.

In this paper designing of microstrip patch antenna has been done. Further to improve the results obtained from single layer patch stack arrangement has been done. This paper presents a stack arrangement of microstrip patch antenna to improve the bandwidth for communication. For this purpose IE3D software has been taken for experimental study. Planer designs are mostly preferred for these structures, due to their advantages of small size, low manufacturing cost and conformabilty. Microstrip patch antenna of 20mm×20 mm size is designed on a FR4 substrate of thickness 1.59mm and relative permittivity of 4.4 and mounted above the ground plate at a height of 6mm. A stack of size 18×18mm is fabricated with air gap between them. High Bandwidth is obtained with stable pattern characterization, such as gain and polarization within its bandwidth. Impedance matching is also observed for this case. Details of the measured and simulated results are presented and discussed in this paper.

This paper focuses on the commissioning process of pipeline on hilly areas (for short, hereinafter referred to as hilly pipeline). Quasi-steady model is established to simulate the hydraulic characteristics of it. Liquid holdup in pipeline with various parameters such as diameter, flow rate, inclination is calculated and analyzed. Variation trend of liquid height of slug and gas pressure of air pocket is emphatically studied and entrainment effect is further considered in the model. According to the calculation result, although entrainment effect can counterbalance the increase of gas pressure of the air pocket to a certain extent, its effect is not significant. The proposed model and research results quantitatively obtained in this paper may provide guidance for the practical commissioning process.

The design of control systems in large-scale CPV power plants will be more challenging in the future. Reasons are the increasing size of power plants, the requirements of grid operators, new functions, and new technological trends in industrial automation or communication technology. Concepts and products from fixed-mounted PV can only partly be adopted since control systems for sun-tracking installations are considerable more complex due to the higher quantity of controllable entities. The objective of this paper is to deliver design considerations for next generation control systems. Therefore, the work identifies new applications of future control systems categorized into operation, monitoring and maintenance domains. The key-requirements of the technical system and the application layer are identified. In the resulting section, new strategies such as a more decentralized architecture are proposed and design criteria are derived. The contribution of this paper should allow manufacturers and research institutes to consider the design criteria in current development and to place further research on new functions and control strategies precisely.

Wrinkling is one of the major defects in forming processes of auto-body panels. This paper focuses on application of universal formability technology to analyze and eliminate wrinkling defect. To analyze refinedly and eliminate efficiently, universal formability technology is introduced into finite element environment. This paper presents a procedure of formability simulation analysis for wrinkles appeared on an auto fender model. The analysis results provide the approaches to eliminating wrinkles, which demonstrates the effectiveness of universal formability technology to analyze wrinkling phenomenon. The study also shows the feasibility of universal formability technology introduced into finite element environment.

Two phase titanium alloy-TC11 alloy and Superalloy-IN718 alloy are being considered for high-temperature structural applications in aero-engine because of their excellent mechanical properties at elevated temperatures. The mechanical properties of their forgings are sensitive to the microstructure. Therefore, it is crucial to obtain a corresponding microstructure by controlling the hot working process. For the forging of TC11 alloy, the ingot break down in the subtransus region is an important process which acted as the primary role in the transformation of lamellar structure to equiaxed one as well as its poor formability because of lower deformation temperature. In this paper, the lamellar globularization kinetics and fracture behavior during forging are studied and modeled. For the hot forging of IN718 alloy. the grain size evolution is an important process. As the δ phase in the alloy can control grain growth through the strong pinning effect, the effect of δ phase on the microstructure evolution during hot working has been considered in this paper, and the microstructure evolution model has been established. As a applications, The lamellar globularization and fracture during the subtransus cogging process of large size TC11 alloy billet, and the microstructure development during the hot forging process of IN718 alloy turbine disk have been investigated commercial FE Software with user subroutines. The prediction results showed good agreement with the actual ones.

As advancing application of soft computation technique in oil and gas industry, Genetic Algorithm (GA) also shows contribution in geophysical inverse problems in order to achieve better results and efficiency in computational process. In this paper, I would like to show the progress of my work in inverse modeling of time-lapse gravity data uses value encoding with alphabet formulation. The alphabet formulation designed to provide solution of characterization positive density change (+Δρ) and negative density change (-Δρ) respect to reference value (0 gr/cc). The inversion that utilize discrete model parameter, computed with GA as optimization algorithm. The challenge working with GA is take long time computational process, so the step in designing GA in this paper described through evaluation on GA operators performance test. The performances of several combinations of GA operators (selection, crossover, mutation, and replacement) tested with synthetic model in single-layer reservoir. Analysis on sufficie...

This paper is a review of the LDA(GGA)-1/2 method for band calculation. We review the many applications of the method: band gaps, semiconductor interfaces, semiconductor alloys. The number of applications where the method fails is minimal. Leading to results with a precision comparable to Hedin’s GW method, LDA-1/2 has the advantage of being orders of magnitude faster. The paper begins by a short theoretical review in which we try not repeat what is already published. Then we present some results that are scattered in the literature. We find that LDA(GGA)-1/2 is the recommended method for excited state energy calculations.

Operator allocation is one of the most important decisions that can affect productivity in labor-intensive manufacturing system. Improper decision on operator allocation will reduce company's throughput and increase waste. Therefore, all factors such as operators' performance and operational constraints need to be considered in making the best operator allocation decision. Most of previous studies used two phases methodology. In two phases methodology, they used operational constraints and treated all operators to have the same level of performance for making decision on operator allocation. Therefore, in this paper a three-phase methodology is proposed to determine the optimal operator allocation. This methodology advances the existing approach on operator allocation by combining operators' performance and operational constraints. The methodology starts with evaluating the operators' performance. Then, it is followed with determining inputs and outputs for operator allocation alternatives and it ends with determining the optimal operator allocation. This paper will give ideas and directions to the management of the manufacturing company in determining the optimal operator allocation decision.

With high level of business competition, it is vital to have flexible staff that are able to adapt themselves with work circumstances. However, staff selection process is not an easy task to be solved, even when it is tackled in a simplified version containing only a single criterion and a homogeneous skill. When multiple criteria and various skills are involved, the problem becomes much more complicated. In adddition, there are some information that could not be measured precisely. This is patently obvious when dealing with opinions, thoughts, feelings, believes, etc. One possible tool to handle this issue is by using fuzzy set theory. Therefore, the objective of this paper is to review the existing fuzzy techniques for solving staff selection process. It classifies several existing research methods and identifies areas where there is a gap and need further research. Finally, this paper concludes by suggesting new ideas for future research based on the gaps identified.

In the present paper, the main factors which influence the accuracy of springback simulation are discussed, and the optimized parameters, which aim at obtaining an accurate springback simulation, and the full cycle simulation, which aims at the closest boundary condition between simulation and practice, are discussed. As a verification and comparison, an experimental part, Aluminum hood outer, is used and some good results are achieved. Based on the result of the springback verification, the minimum clamping concept for springback compensation is discussed and the compensation strategy is determined according to the springback behavior in different operations. Moreover, the springback in the car position and in the inspection tool is compared and a methodology of springback compensation without gravity is put forward. In the end, the basic principles of the rebuilding of class A surface is discussed and the comparison of geometrical deviation of the final part in tryout is given in this paper.

The use of analysis techniques for industrial controller's analysis, such as Simulation and Formal Verification, is complex on industrial context. This complexity is due to the fact that such techniques require sometimes high investment in specific skilled human resources that have sufficient theoretical knowledge in those domains. This paper aims, mainly, to show that it is possible to obtain a timed automata model for formal verification purposes, considering the CAD model of a mechanical component. This systematic approach can be used, by companies, for the analysis of industrial controllers programs. 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. A library for formal verification purposes is obtained from original 3D CAD models using Software as a Service platform (SaaS) that, nowadays, has become a common deliverable model for many applications, because SaaS is typically accessed by users via internet access.

We showed our work on modeling turbine blade crack detection in Sonic Infrared (IR) Imaging with a method of creating flat crack surface in finite element analysis (FEA) in last year's QNDE paper. This modeling has been carried out continuously as part of model-assisted study on crack detection in aircraft engine turbine blades. We have presented that Sonic IR Imaging NDE is a viable method to detect defects in various structures. It combines ultrasound excitation for frictional heating in defects and infrared imaging to sense this heating, and thus to identify the defects. It is a fast wide-area imaging technology. It only takes a second to image a large area of a target sample. When an aircraft is in flight, the turbine engine blades operate under high temperature and high cyclic stresses. Thus, fatigue cracks can form after many hours of operation. Sonic IR Imaging can be used to detect such cracks. However, we still need to better understand contributions of parameters/factors in the crack detection process with Sonic IR Imaging. FEA modeling can help us to reveal certain aspects through the data it produces where experimental work cannot achieve. Upon the model we presented last year, a two-step simulation process was designed to simulate the important aspects in our experiments. These include a newly designed model for the ultrasound transducer which delivers mechanical energy to the sample and the implementation of static force while engaging the transducer to the sample. In this paper, we present the ideas and the results from the new model.

Thermal Barrier Coatings (TBC) are used to reduce the working temperature of the high pressure turbine blade metal surface and hence permit engines to operate at higher temperatures/ efficiencies. A sensor TBC is an adaptation of existing TBCs to enhance their functionality, such that they become sensors and allow measurement of component temperatures. The sensing capability is introduced by embedding optically active materials into the TBC and by illuminating these coatings with excitation light phosphorescence can be observed. The phosphorescence carries temperature and structural information about the coating. This paper describes the first ever implementation of a sensor coating system on a full-scale jet engine. The system consists of three main components: industrially manufactured coatings, advanced remote detection optics with large stand-off distances and tailored control and readout software. The majority of coatings were based on yttrium stabilized zirconia doped with Dy and Eu, although other coatings were manufactured, too. Coatings were produced on a production line using atmospheric plasma spraying. An advanced optical system was designed, manufactured and operated permitting scanning of coated components using a wide acceptance angle. Successful measurements were taken from the nozzle guide vanes at the inlet to the turbine section and are reported in the paper.

This new session at QNDE reflects the growing interest in inspection automation. Our paper describes a newly developed platform that makes the complex NDE automation possible without the need for software programmers. Inspection tasks that are tedious, error-prone or impossible for humans to perform can now be automated using a form of drag and drop visual scripting. Our work attempts to rectify the problem that NDE is not keeping pace with the rest of factory automation. Outside of NDE, robots routinely and autonomously machine parts, assemble components, weld structures and report progress to corporate databases. By contrast, components arriving in the NDT department typically require manual part handling, calibrations and analysis. The automation examples in this paper cover the development of robotic thickness gauging and the use of adaptive contour following on the NRU reactor inspection at Chalk River.

In paper industry, refining the pulp suspension is a costly operation due to the high energy consumed. Nevertheless, this operation is necessary to develop the mechanical properties of the future sheet of paper. Refiners look like hydrodynamic bearing loads, consequently the lubrication theory may be applied. We add to the pioneering work of Rance and Steenberg, the numerical resolution of the Reynolds equation when the local geometry of the bearing load is defined. The validation of this approach was obtained comparing the experimental and theoretical data of the friction coefficient versus the average gap clearance.

This paper identifies the influence variables affecting the resolution of thermometry resistance bridges. The theoretical limit to the resolution is determined by the spectral density of all noise sources, including the thermal noise from the resistors and amplifiers, quantization noise, and the equivalent noise bandwidth. Optimization of resolution is equivalent to minimization of measurement time, which has a Heisenberg-uncertainty-like relationship with equivalent noise bandwidth. Bridge design has a major influence on the compromises between the different noise sources, as well as influencing compromises with respect to measurement time. The paper explains the concept of an ideal averaging filter and illustrates the use of the Allan variance to evaluate the dependence of the resolution on measurement time.

The paper describes different studies linked to extrusion problems encountered during production in the cable industry. Extrusion simulation or rheology analysis can be used to understand the origin of the problems in cable manufacturing and to set up durable industrial solutions by selecting the appropriate compounds, optimizing screw profiles, modifying the geometries of the tooling or adapting the processing conditions. Our investigations based on the COMPUPLAST® Virtual Extrusion Laboratory™ software, have brought large understanding and these investigations are cheaper and faster alternatives to real experiments (trials/errors) when analyzing and optimizing extrusion processes. Three examples are presented in the paper.

Phased array ultrasonic reconstruction techniques are often presented as a prospect for better and enhanced diagnosis. However to date few applications of these techniques can be found in the industry, partly because of questions on sizing but also because they often require heavy acquisitions. A way forward is then to propose techniques requiring less intensive data acquisition to make them broadly affordable in practice. Several approaches ranging from full matrix capture to paintbrush acquisitions are presented in this paper in combination with associated reconstruction processing like the Total Focusing Method (TFM) and the Time Domain Topological Energy (TDTE) techniques. Emphasis is given to their relative relevancies and practical applicability on typical configurations of interest for industries. The paper also presents recent efforts made on the acceleration of processing computation times, in particular through the use of GPU architectures.

Guided wave structural health monitoring (SHM) has been proposed as a technique to allow permanently attached sensors to provide information about the state of a structure. Typical approaches rely on gathering information about the baseline state of the structure and using this data with subtraction to highlight changes to the system. This relies on the baseline data accurately representing the conditions that the system will experience. In reality this is difficult to ensure and may result in either large periods out of service or poor performance. In addition the size of the baseline set can become prohibitively large. This paper describes an alternative approach that produces an efficient continuously evolving baseline. The paper considers how damage detection performance can be characterized within this framework and presents a series of metrics to do this. The result is a new way of considering the baseline problem with practical applications to the long term inspection of structures.

Road Infrastructure (RI) project evaluation and selection is concern with the allocation of scarce organizational resources. In this paper, it is suggest an improved RI project selection methodology which reflects interdependencies among evaluation criteria and candidate projects. Fuzzy Delphi Method (FDM) is use to evoking expert group opinion and also to determine a degree of interdependences relationship between the alternative projects. In order to provide a systematic approach to set priorities among multi-criteria and trade-off among objectives, Analytic Network Process (ANP) is suggested to be applied prior to Zero-One Goal Programming (ZOGP) formulation. Specifically, this paper demonstrated how to combined FDM and ANP with ZOGP through a real-world RI empirical example on an ongoing decision-making project in Johor, Malaysia.

The appearance of automotive skin panels creates desirability for a product and differentiates it from the competition. Because of the importance of skin panels, considerable care is taken in minimizing defects such as the 'hollow' defect that occur around door-handle depressions. However, the inspection process is manual, subjective and time-consuming. This paper describes the development of an objective and inspection scheme for the 'hollow' defect. In this inspection process, the geometry of a panel is captured using a structured lighting system. The geometry data is subsequently analyzed by a purpose-built wavelet-based algorithm to identify the location of any defects that may be present and to estimate the perceived severity of the defects without user intervention. This paper describes and critically evaluates the behavior of this physically-based algorithm on an ideal and real geometry and compares its result to an actual audit. The results show that the algorithm is capable of objectively locating and classifying 'hollow' defects in actual panels.

In this paper authors present the set of data on the factors affecting the implementation of construction projects in Poland. To develop that data, surveys were conducted among companies and engineers working in construction industry. The result of the paper is classification of the factors affecting the implementation of construction projects, due to the degree of significance. Elements of the fuzzy sets theory were applied, to order those factors, and to develop their formal description. Authors also describe possibility of using ordered factors, to determine the potential risk of variability of the implementation factors. This could be the basis for the design of construction projects in Polish conditions.

This paper presents a simple way to form non-diffracting narrow beams, also called bessel beams, with phased arrays. Normally non-diffracting beams are generated by using axiconi-cal lenses. The axiconical lens is simulated by phased array ultrasonic technique using a delay time distribution that is chosen according to the sound path in axiconical lenses. The phased array probe is a 2D matrix array with 121 elements. Each element is driven by another delay time. The delay times which are usually used for this probe to focus in different depth of the material are distributed spherical-ly over the area of the probe. To form a non-diffracting beam the distribution of the time delays is linearly increasing to the center of the probe. In the paper the results of the simulation are given. By varying the parameters in the simulation the best setting is chosen. With this an experiment is done and the expe-rimental results are compared to the simulation results. Considerations on the best probe to form non-diffracting beams with phased array are described.

The world-wide ageing and deteriorating civil infrastructure network has necessitated the development of new Structural Health Monitoring (SHM) approaches that are capable of producing quantitative feedback on fracture mechanisms in critical civil structures such as bridges in real-time. In this paper, we present a methodology that combines techniques applied in quantitative seismological analyses with the enabling capabilities of the Acoustic Emission (AE) technique in order to gain insight into ongoing fracture processes in concrete structures. The proposed methodology employs the technique of Moment Tensor Inversion (MTI), a key analysis tool in seismology, in order to develop a full understanding of the physics of the source of fracture and infer its properties. The MTI technique is simple in concept but solution accuracy is highly dependent on the sampling of the wavefield in 3-D, especially in the case where the sensors are all uniaxial. For accuracy purposes, all our experiments were performed using high-fidelity Glaser/NIST point-contact sensors that show a flat response for frequencies between 20 kHz and 1 MHz. In this paper, we provide a general description of the proposed methodology with emphasis on the so-called hybrid MTI technique. Finally, we present a set of initial experiments conducted in the laboratory using repeatable artificial AE sources and we discuss the results.

During the recent 10-15 years, Computer Aided Process Planning and Die Design evolved as one of the most important engineering tools in sheet metal forming, particularly in the automotive industry. This emerging role is strongly emphasized by the rapid development of Finite Element Modeling, as well. The purpose of this paper is to give a general overview about the recent achievements in this very important field of sheet metal forming and to introduce some special results in this development activity. Therefore, in this paper, an integrated process simulation and die design system developed at the University of Miskolc, Department of Mechanical Engineering will be analyzed. The proposed integrated solutions have great practical importance to improve the global competitiveness of sheet metal forming in the very important segment of industry. The concept described in this paper may have specific value both for process planning and die design engineers.

The performance of thermal control systems has, in recent years, improved in numerous ways due to developments in control theory and information technology. The shell-and-tube heat exchanger (STHX) is a medium where heat transfer process occurred. The accuracy of the heat exchanger depends on the performance of both elements. Therefore, both components need to be controlled in order to achieve a substantial result in the process. For this purpose, the actual dynamics of both shell and tube of the heat exchanger is crucial. In this paper, optimal reliability-based multi-objective Pareto design of robust state feedback controllers for a STHX having parameters with probabilistic uncertainties. Accordingly, the probabilities of failure of those objective functions are also considered in the reliability-based design optimization (RBDO) approach. A new multi-objective uniform-diversity genetic algorithm (MUGA) is presented and used for Pareto optimum design of linear state feedback controllers for STHX problem. In this way, Pareto front of optimum controllers is first obtained for the nominal deterministic STHX using the conflicting objective functions in time domain. Such Pareto front is then obtained for STHX having probabilistic uncertainties in its parameters using the statistical moments of those objective functions through a Hammersley Sequence Sampling (HSS) approach. It is shown that multi-objective reliability-based Pareto optimization of the robust state feedback controllers using MUGA includes those that may be obtained by various crisp threshold values of probability of failures and, thus, remove the difficulty of selecting suitable crisp values. Besides, the multi-objective Pareto optimization of such robust feedback controllers using MUGA unveils some very important and informative trade-offs among those objective functions. Consequently, some optimum robust state feedback controllers can be compromisingly chosen from the Pareto frontiers.The performance of thermal control systems has, in recent years, improved in numerous ways due to developments in control theory and information technology. The shell-and-tube heat exchanger (STHX) is a medium where heat transfer process occurred. The accuracy of the heat exchanger depends on the performance of both elements. Therefore, both components need to be controlled in order to achieve a substantial result in the process. For this purpose, the actual dynamics of both shell and tube of the heat exchanger is crucial. In this paper, optimal reliability-based multi-objective Pareto design of robust state feedback controllers for a STHX having parameters with probabilistic uncertainties. Accordingly, the probabilities of failure of those objective functions are also considered in the reliability-based design optimization (RBDO) approach. A new multi-objective uniform-diversity genetic algorithm (MUGA) is presented and used for Pareto optimum design of linear state feedback controllers for STHX problem....

This paper presents a study regarding the experimental validation of a mathematical model used to simulate the electric arc behavior, taking into consideration a technological phase of the electric arc furnace process. In order to do this, the mathematical model of the electric arc was implemented in Simulink software. In this paper were presented results obtained in the meltdown stage of the charging material. This model can be useful from the point of view of power quality analysis and electric arc control. Results obtained by simulation were compared with measured data.

This paper provides a study and analysis of the extremely busy booking counters at the Megaplex in Dubai using the queuing model and simulation. Dubai is an emirate in UAE with a multicultural population. Majority of the population in Dubai is foreign born. Cinema is one of the major forms of entertainment. There are more than 13 megaplexes each with a number of screens ranging from 3 to 22. They screen movies in English, Arabic, Hindi and other languages. It has been observed that during the weekends megaplexes attract a large number of crowd resulting in long queues at the booking counters. One of the busiest megaplex was selected for the study. Queuing theory satisfies the model when tested in real time situation. The concepts of arrival rate, service rate, utilization rate, waiting time in the system, average number of people in the queue, using Little's Theorem and M/M/s queuing model along with simulation software have been used to suggest an empirical solution. The aim of the paper is twofold-To assess the present situation at the Megaplex and give recommendations to optimize the use of booking counters.

Springback compensation is one of the key topics in current die face engineering. The accuracy of the springback simulation, the robustness of method planning and springback are considered to be the main factors which influences the effectiveness of springback compensation. In the present paper, the basic principles of springback compensation are presented firstly. These principles consist of an accurate full cycle simulation with final validation setting and the robust process design and optimization are discussed in detail via an industrial example, a decklid inner. Moreover, an effective compensation strategy is put forward based on the analysis of springback and the simulation based springback compensation is introduced in the phase of process design. In the end, the final verification and comparison in tryout and production is given in this paper, which verified that the methodology of robust springback compensation is effective during the die development.

Dynamic Gas Bearing Turbines - although applied for helium refrigerators and liquefiers for decades - experienced limitations for hydrogen applications due to restrictions in axial bearing capacity. With a new design concept for gas bearing turbines developed in 2004, axial bearing capacity was significantly improved enabling the transfer of this technology to hydrogen liquefiers. Prior to roll-out of the technology to industrial plants, the turbine bearing technology passed numerous tests in R&D test benches and subsequently proved industrial scale demonstration at Linde Gas' hydrogen liquefier in Leuna, Germany. Since its installation, this turbine has gathered more than 16,000 successful operating hours and has outperformed its oil bearing brother in terms of performance, maintainability as well as reliability. The present paper is based on Linde Kryotechnik AG's paper published in the proceedings of the CEC 2009 concerning the application of Dynamic Gas Bearing Turbines in hydrogen applications. In contrast to the former paper, this publication focuses on the steps towards final market launch and more specifically on the financial benefits of this turbine technology, both in terms of capital investment as well as operating expenses.

Jordan has significant oil shale deposits occurring in 26 known localities. Geological surveys indicate that the existing deposits underlie more than 60% of Jordan's territory. The resource consists of 40 to 70 billion tones of oil shale, which may be equivalent to more than 5 million tones of shale oil. Since the 1960s, Jordan has been investigating economical and environmental methods for utilizing oil shale. Due to its high organic content, is considered a suitable source of energy. This paper introduces a circulating fluidized bed combustor that simulates the behavior of full scale municipal oil shale combustors. The inside diameter of the combustor is 500 mm, the height is 3000 mm. The design of the CFB is presented. The main parameters which affect the combustion process are elucidated in the paper. The size of the laboratory scale fluidized bed reactor is 3 kW, which corresponds to a fuel-feeding rate of approximately 1.5 kg/h.

A new scanning laser hear has been designed for measuring up to 6 degrees of freedom at a point. The scanning head is supported by a rotating hallowed shaft, which allows the laser beam to travel up to the scanning head. A set of two mirrors deflects the laser beam with an angle and the rotation of the scanning head produces a conical scan. This work shows that this device can perform a conical scan whose the very small circle scan, before and after the focus point, can measure up to 6 degrees of freedom; the paper focuses on the in-plane rotation. A validation of the novel scanning head is performed. This paper concludes with the presentation of a more compact design for the 6DOF scanning head, which is aimed for complex engineering applications.

This paper describes an approach for measuring material degradation using nonlinear acoustics. The importance of this measurement is that prior efforts have shown that the degree of acoustic nonlinearity increases as a function of fatigue damage accumulation. By exploiting this physical mechanism, there is the potential to develop methods for measuring the remaining life of critical components. The challenge with existing approaches for measuring acoustic nonlinearity is that primarily they have only been shown to be successful in a laboratory setting. This paper presents a potential approach for field measurement of acoustic nonlinearity that utilizes Rayleigh waves generated from electromagnetic acoustic transducers (EMATs). Rayleigh waves have unique advantages because the sound propagates along the surface, allowing for application on complex engineering structures. EMATs were used in place of traditional piezoelectric transducers because the sound is generated directly in the metallic structure, eliminating the need for sound coupling fluids that are a source of variability. Custom EMATs were developed and nonlinearity measurements were performed on 410 stainless steel specimens that were subjected to a fatigue process. Some experiments showed an increase in the acoustic nonlinearity of up to 500% compared to the unfatigued value. Other experiments had too much scatter and did not show this relationship consistently due to unanticipated challenges in producing repeatable measurements. Lessons learned from the project effort will be presented to potentially improve the repeatability of the measurement approach. If the scatter can be reduced, this EMAT-based technique could result in a field deployable prognosis tool.