bluuebunny/crossref_metadata_2025 huggingface dataset:
Electromagnetic Examination of Hydrogen Attack in AISI 4340 Steel
Authors: Grimberg Raimond  , Savin Adriana  , Rebello Joao
Published: February 2025

This paper presents an electromagnetic method for detection of cracks with micrometric features, created in ferromagnetic AISI 4340 steel block by the hydrogen attack. The proposed method is based on the absolute send-receive electromagnetic transducer having a rectangular frame circulated by a high frequency current as emission and a metamaterials lens that has optimal functioning at the same frequency as the excitation current as reception. Cracks with 5μm width and approximate 205μm depth have been detected. The simulations effectuated have shown the impossibility to use classical eddy current transducers for this problem.
Evaluation of Phases Proportions in Welded Joints of Duplex Stainless Steel by Ferritoscope and Metallographic Replica Analyses
Authors: Tavares Sérgio S.M.  , Pardal Juan M.  , de Souza Guttemberg C.  , Cindra Fonseca Maria P.  , Martins José L.F.  , Moura Elineudo P.  , Cardote Filho Ismael
Published: February 2025

Duplex stainless steels are high strength and corrosion resistant alloys, whose properties are devoted to the fine microstructure composed by similar amounts of ferrite and austenite and also to the high concentrations of Cr, Mo and N in solid solution. Not for coincidence, duplex steels are extensively used in chemical and petrochemical industries. However, welding operations conditions can promote the unbalance of the ferrite/austenite proportions mainly in the welding metal, with decrease of the properties mentioned. For this reason, non destructive measurements of ferrite content, by ferritoscope, is used after welding pipes. Ferritoscope is a commercial instrument which uses the initial magnetic permeability to analyze the ferrite content in duplex and austenitic stainless steels. The inspection with ferritoscope is a procedure commonly used in building and assembly of spools of duplex and superduplex stainless steels. The objective of this work was to evaluate the amounts of phases in the welding metal for different spools welded in the field by use of ferritoscope and metallographic replica techniques. The results showed that the two techniques measured similar values of ferrite and austenite, but ferritoscope analysis can be influenced by shape and surface conditions of the welded joint.
Nondestructive Investigation Based on THz Waves
Authors: Thomas D.H.  , Cordes A.H.  , von Der Weid J.P.
Published: February 2025

THz waves can indeed become a powerful tool for NDE of non-metallic industrial equipment. We show how a standard THz-TDS system in the transmission configuration can be used to evaluate the quality of glued joints in non-metallic samples.
Uncertainties of MFL Signal Inversion and Worst-Case Defect Depth Estimation using a Numerical Model
Authors: Priewald Robin H.  , Ledger Paul D.  , Pearson Neil R.  , Mason John S.D.
Published: February 2025

The Magnetic flux leakage (MFL) method is commonly employed for the non-destructive evaluation (NDE) of steel plates used in the construction of oil storage tanks and pipelines, where large areas have to be covered within a short time. Due to fundamental characteristics of the MFL method, very narrow and deep pipe-type defects can produce very similar signals to wide and shallow lake-type defects. This inherent uncertainty of MFL can cause dangerous misinterpretations of the measurement data as crucially deep defects could remain unnoticed.
Three-dimensional Numerical Investigations of Lorentz Force Eddy Current Testing
Authors: Zec Mladen  , Uhlig Robert P.  , Ziolkowski Marek  , Brauer Hartmut
Published: February 2025

In this work, we perform three-dimensional finite element simulations of a solid electrically conducting bar with pre-defined material defects moving across static magnetic field lines of a permanent magnet. This study is motivated by the novel non-destructive testing technique called Lorentz force eddy current testing (LET), which is based on the measurement of the Lorentz forces acting on the magnet. In particular, we perform parametric studies to quantify the effect of various parameters on perturbations of the Lorentz force, such as: defect depth, testing speed, electrical conductivity, and magnet position. The analyses provide reference results to understand the feasibility and testing capabilities of LET. The experimental validation of the numerical results is presented as well.
Large Scale 3D FEM Electromagnetic Simulations and Validations for FBR Steam Generator Tubes
Authors: Mihalache Ovidiu  , Yamaguchi Toshihiko  , Ueda Masashi
Published: February 2025

This paper presents 3D finite element simulations of the In-Service Inspection of ferromagnetic steam generator tubes of Fast Breeder Reactors. 3D FEM models, resulting in large scale electromagnetic eddy current computations with up to 5,100,000 2nd order tetrahedrons are analyzed using parallel simulations with 1024 CPUs on Fujitsu BX900 and using an in-house developed code 3D-RFECT. Validations of FEM simulations with experimental measurements for helical tubes are conducted for a large model of SG tubes support plate and three SG tubes attached to it at various frequencies. ISI of SG tubes using ECT and detection of defects for large SP models are validated trough 3D FEM simulations.
Threats to Energy Resources and Infrastructure
Authors: Staff
Published: February 2025

The world energy infrastructure is vulnerable to a variety of man-made and natural disasters. Cyberattacks are an emerging threat that grows daily in its ability to create energy shortages on a grand scale. War, both conventional and unconventional, has the possibility to cause huge energy disruptions in a region or even in the whole world. Crime, both economic and political, rages from the small, localized stealing to the piracy (and often ransom) or large tanker ships. The world needs to come together to be able to address these threats in a comprehensive manner.
Protecting Pipelines - BTC as a Case Study
Authors: Staff
Published: February 2025

Energy security does not depend upon just the supply but also the transportation infrastructure, much of which are pipelines. Pipelines can be vulnerable to attack, particularly in Turkey where 22,000 km of pipelines carry 4% of the world’s daily oil production. In addition to terrorism, there are other threats to pipelines. Unless it is willing to post guards at every ten meters, a company will have to take measures to allocate resources to meet the highest risk. This article discusses the BTC approach to pipeline security.
Valuable and Vulnerable: Protecting Maritime Infrastructure
Authors: Wilson Brian
Published: February 2025

For nations bordering on oceans, security of the sea borders is a must. The oceans are not the only place where illicit activity occurs, but they are uniquely vast, jurisdictionally challenging, and operationally complex. Merchant vessels do not strictly move in controlled channels or according to fixed time parameters like planes and can carry potentially legitimate cargo capable of causing great destruction. Not every threat manifests itself clearly: the scope of maritime security challenges is immense. Maritime infrastructure protection consists of risk management and maritime domain awareness (MDA). Protecting maritime infrastructure is particularly challenging because threats are not always clear and are often preceded by ambiguous signals, uncertain events and incomplete information.
Computer Network Defense: New Threats and Trends
Authors: Rigoni Andrea  , Lindstrom Gustav
Published: February 2025

New technology trends invariably impact prospects for computer network defense (CND) – including the protection of critical infrastructures and services. Three evolving trends that stand out in particular include: 1) critical infrastructures' increasing reliance on commercial off the shelf (CoTS) technologies; 2) societies' growing reliance on mobile technologies coupled with a movement towards the ‘Internet of Things;’ and 3) the advent of cloud computing and big data. While these ICT trends contribute to economic growth and development, they will also generate new vulnerabilities, many of which may negatively impact segments of society. While policymakers play an important role in strengthening cyber security and resiliency, they may not always fully grasp the security implications of these and other technology trends – including the potential for ripple effects across different critical services and sectors. Minimizing this knowledge gap, as well as bringing tighter alignment and shared understanding of the operational realities and policy implications associated with new trends, is essential to promote effective computer network defense.
Characterizing Performance of Applications on Blue Gene/Q
Authors: Baumeister Paul F  , Boettiger Hans  , Hater Thorsten  , Knobloch Michael  , Maurer Thilo  , Nobile Andrea  , Pleiter Dirk  , Vandenbergen Nicolas
Published: February 2025

Recently the latest generation of Blue Gene machines became available. In this paper we introduce general metrics to characterize the performance of applications and apply it to a diverse set of applications running on Blue Gene/Q. The applications range from regular, floating-point bound to irregular event-simulator like types. We argue that the proposed metrics are suitable to characterize the performance for a larger set of computational science applications running on today's massively-parallel systems. They therefore do not only allow to assess usability of the Blue Gene/Q architecture for the considered (types of) applications. They also provide more general information on application requirements and valuable input for evaluating the usability of various architectural features, i.e. information, which is needed for future co-design efforts aiming for exascale performance.
An Efficient Pipelined Implementation of Space-Time Parallel Applications
Authors: Takami Toshiya  , Fukudome Daiki
Published: February 2025

Efficient ways to implement space-time parallel applications based on the parareal-in-time algorithm are studied with a pipelined communication pattern. After analyzing the standard one, a simplified implementation of the parareal-in-time algorithm is introduced for scientific computing problems, where an identity transformation is used as a coarse solver and the pipelined communications are used to resolve dependencies. Based on analysis of the convergence property and expected performance, it is shown that this new implementation is valid for explicit time-evolution calculations. Through performance measurements of time-parallel applications, strategies for the further tuning toward postpeta-scale computing is discussed.
Numerical Simulation of the Low Compressible Viscous Gas Flows on GPU-based Hybrid Supercomputers
Authors: Davydov Alexander A.  , Shilnikov Evgeny V.
Published: February 2025

The paper presents some results of modeling low compressible gas flows on GPU-based hybrid computer systems. Finite difference scheme is based on the Quasi Gas Dynamic (QGD) equations system. The successful experience in solving a wide variety of gas dynamic problems by means of QGD based schemes showed that they describe viscous heat conducting flows as good as schemes for Navier-Stokes equations, where the latter are applicable. To improve the stability condition of the explicit scheme described here the flux relaxation approach was used, which permits to achieve practically Courant like stability condition even for very low Mach numbers. So, it is very convenient for computer systems with hybrid architecture. Parallel realization is based on shmem programming technology. The calculation results show good parallelization efficiency.
NEMORB's Fourier Filter and Distributed Matrix Transposition on Petaflop Systems
Authors: Ribeiro Tiago  , Haefele Matthieu
Published: February 2025

The work presented refers to the calculation of two-dimensional Fourier transforms of distributed data, of which matrix transposition is a major ingredient. The motivation stems from a well-known parallel scalability bottleneck related to Fourier filtering within the global gyrokinetic NEMORB code, whose aim is to simulate plasma turbulence within a Tokamak fusion device. Since this pure MPI code is very HPC-resource demanding, with good scaling up to 65536 tasks, such a bottleneck naturally impairs further parallel scalability. To overcome this limitation the filtering algorithm is modified. Firstly, exploring the Fourier transform Hermitian symmetry of the purely real-valued input data to discard the redundant Fourier modes. This not only reduces the amount of needed computing power but also the amount of communication between MPI tasks during the transpose phase. Secondly, several distributed transpose algorithms are tested and the high count of zeros yielded by the NEMORB's low pass filter is used to further reduce the inter-task data exchange by avoiding communicating zeros. Finally, the behavior of the transpose at the scale of a full petaflop system is explored. Execution time, MPI initialization and memory footprint can become critical on such large runs. Four implementation strategies have been tested and scaling results are shown on four petaflop systems, among which two belong to the PRACE Research Infrastructure.
Numerical Experiments with New Algorithms for Parallel Decomposition of Large Computational Meshes
Authors: Golovchenko Evdokia  , Dorofeeva Elizaveta  , Gasilova Irina  , Boldarev Alexey
Published: February 2025

The paper presents new algorithms for parallel decomposition of large computational meshes. The problem of load balancing arises in parallel mesh-based numerical solution of problems of continuum mechanics, pulsed-power energetics, electrodynamics etc. on high-performance computing systems. Geometric parallelism is commonly used in most of the applications for large-scale 3D simulations of the problems listed above. It implies that every branch of an application code processes a subset of computational mesh (a subdomain), while data exchanges provide a possibility of computations in the vicinity of subdomain borders. In order to increase processors efficiency it is necessary to provide rational domain decomposition, taking into account the requirements of making balanced mesh distribution among processors and reducing interprocessor communications, that depend on the number of bonds between subdomains. A principal goal of the presented work was to design rational parallel decomposition algorithms, working with unstructured meshes with up to 1 billion elements with irregular structure whose cells may be tetrahedrons, triangular or quadrilateral prisms. To this end, the program package for parallel mesh decomposition GRIDSPIDERPAR was developed. The complex includes two algorithms: parallel incremental algorithm of graph partitioning and parallel geometric algorithm of mesh partitioning. The developed algorithms were investigated experimentally in two stages. First we examined a number of “finite volume” meshes built in different geometric domains. For each test mesh we constructed a dual graph and carried out a comparative partitioning into the equal number of subdomains with use of the methods incorporated into PARMETIS, PT-SCOTCH and ZOLTAN versus the techniques of our tool GRIDSPIDERPAR. Second, we performed computer simulations of some problems of magnetohydrodynamics to evaluate the efficiency of the developed algorithms. The results of numerical experiments are presented in this paper.
Compiling a Dataflow-based Language Abstraction onto an FPGA
Authors: Burrows Eva
Published: February 2025

When compiling for reconfigurable hardware from high-level languages, the early phase of the compilation process is concerned with the building of the dataflow graph. This plays a key role in the circuit generation process. Building the dataflow graph automatically is a non-trivial compiler task. Depending on the complexity of the computation, the compiler may not yield the fine-grained solution needed for efficient circuit generation. In this paper, we argue that a suitable dataflow-based language abstraction at the level of the algorithmic description of a computation, i.e., program code, allows the straightforward generation of circuit descriptions. The framework should suit computations with static, scalable data dependencies, certain recursions and dynamic programming methods. Addressing FPGA programming productivity, the approach also provides an intuitive way to reformulate parts of a computation to be realised as hardware circuit.
Interactive Graph Cuts using FPGA
Authors: Kobori Daichi  , Maruyama Tsutomu
Published: February 2025

In this paper, we describe an FPGA system for interactive graph cuts. With this system, a whole image is divided into two regions, objects and their background, based on the regions specified as the objects or background by the user. This procedure can also be applied to video sequences. For the division, a directed graph is generated for each image, the graph is divided using the max-flow algorithm and only the objects are shown to the user. For accelerating these procedures which require irregular memory accesses in nature using an FPGA, efficient data management methods are required. By caching a part of the image data, and by processing the graph on a deeply pipelined circuit, the system achieved 20-30 fps for standard benchmark images.
An Image Filter System based on dynamic partial reconfiguration on FPGA
Authors: Kurita Hisaaki  , Maruyama Tsutomu
Published: February 2025

In this paper, we describe a filter system on FPGA for stream image processing. By the dynamic partial reconfiguration, any new filters can be reconfigured on the FPGA on demand. However, the simple reconfiguration of a new filter may disturb the output stream, because it is not guaranteed that the filter works as designed during its reconfiguration. In our approach, the system consists of two parts; N filters and two networks to connect them. By limiting the number of the active filters to N – 1, and using one of the networks in turn, any combination of the filters can be realized without disturbing the output stream.
Managing Complexity in the Parallel Sparse Grid Combination Technique
Authors: Larson J.W.  , Strazdins P.E.  , Hegland M.  , Harding B.  , Roberts S.  , Stals L.  , Rendell A.P.  , Ali Md.M.  , Southern J.
Published: February 2025

Parallel implementation of the sparse grid combination technique in high dimensions presents many complexity challenges. We enumerate these challenges, classifying them respectively as computational, algorithmic, and software complexity. We discuss strategies for overcoming the individual complexity barriers. We describe our architecture for a software framework that will allow its users to build complex multiple grid solver applications.
Empirical performance modeling of GPU kernels using active learning
Authors: Balaprakash Prasanna  , Rupp Karl  , Mametjanov Azamat  , Gramacy Robert B.  , Hovland Paul D.  , Wild Stefan M.
Published: February 2025

We focus on a design-of-experiments methodology for developing empirical performance models of GPU kernels. Recently, we developed an iterative active learning algorithm that adaptively selects parameter configurations in batches for concurrent evaluation on CPU architectures in order to build performance models over the parameter space. In this paper, we illustrate the adoption of the algorithm when concurrent evaluations are not possible, which is particularly useful in the absence of GPU clusters. We present an empirical study of the algorithm on a diverse set of GPU kernels and hardware. We show that even when concurrent evaluations are not possible, the default batch mode of the algorithm yields better models and the iterative active learning algorithm reduces the overall time required to obtain high-quality empirical performance models for GPU kernels.
Crowdtuning: systematizing auto-tuning using predictive modeling and crowdsourcing
Authors: Memon Abdul  , Fursin Grigori
Published: February 2025

Software and hardware co-design and optimization of HPC systems has become intolerably complex, ad-hoc, time consuming and error prone due to enormous number of available design and optimization choices, complex interactions between all software and hardware components, and multiple strict requirements placed on performance, power consumption, size, reliability and cost.
Potentials and Limitations for Energy Efficiency Auto-Tuning
Authors: Schöne Robert  , Knüpfer Andreas  , Molka Daniel
Published: February 2025

With an objective target of 20 MW for an Exascale system, the power budget for future super computers has a severe restriction. Fortunately, current hardware and runtime environments feature various adjustable parameters that can be changed at runtime in order to confine the power usage. We present an overview of the potentials and limitations of several power saving mechanisms and describe the integration of energy efficiency optimizations in existing performance analysis tools. We also introduce an energy efficiency tuning cycle and exemplify its usage.
Towards Petaflops Capability of the VERTEX Supernova Code
Authors: Marek Andreas  , Rampp Markus  , Hanke Florian  , Janka Hans-Thomas
Published: February 2025

The VERTEX code is employed for multi-dimensional neutrino-radiation hydrodynamics simulations of core-collapse supernova explosions from first principles. The code is considered state-of-the-art in supernova research and it has been used for modeling for more than a decade, resulting in numerous scientific publications. The computational performance of the code, which is currently deployed on several high-performance computing (HPC) systems up to the Tier-0 class (e.g. in the framework of the European PRACE initiative and the German GAUSS program), however, has so far not been extensively documented. This paper presents a high-level overview of the relevant algorithms and parallelization strategies and outlines the technical challenges and achievements encountered along the evolution of the code from the gigaflops scale with the first, serial simulations in 2000, up to almost petaflops capabilities, as demonstrated lately on the SuperMUC system of the Leibniz Supercomputing Centre (LRZ). In particular, we shall document the parallel scalability and computational efficiency of VERTEX at the large scale and on the major, contemporary HPC platforms. We will outline upcoming scientific requirements and discuss the resulting challenges for the future development and operation of the code.
Scaling of the GROMACS 4.6 molecular dynamics code on SuperMUC
Authors: Kutzner Carsten  , Apostolov Rossen  , Hess Berk  , Grubmüller Helmut
Published: February 2025

Here we report on the performance of GROMACS 4.6 on the SuperMUC cluster at the Leibniz Rechenzentrum in Garching. We carried out benchmarks with three biomolecular systems consisting of eighty thousand to twelve million atoms in a strong scaling test each. The twelve million atom simulation system reached a performance of 49 nanoseconds per day on 32,768 cores.
Execution Schemes for the NPB-MZ Benchmarks on Hybrid Architectures: A Comparative Study
Authors: Dümmler Jörg  , Rünger Gudula
Published: February 2025

Modern high performance platforms increasingly exhibit a hybrid system architecture with two types of execution resources: multicore CPUs and additional GPUs. To obtain the maximum performance on these CPU+GPU architectures, it is important to structure parallel applications in such a way that all execution resources can be exploited efficiently. This includes the decomposition of the application into subtasks and the selection of appropriate execution resources for these subtasks.
Cudagrind: A Valgrind Extension for CUDA
Authors: Baumann Thomas M.  , Gracia José
Published: February 2025

Valgrind [1], and specifically the included tool Memcheck, offers an easy and reliable way for checking the correctness of memory operations in programs. This works in an unintrusive way where Valgrind translates the program into intermediate code and executes it on an emulated CPU. The heavy weight tool Memcheck uses this to keep a full shadow copy of the memory used by a program and tracking accesses to it. This allows the detection of memory leaks and checking the validity of accesses.
Profiling Hybrid HMPP Applications with Score-P on Heterogeneous Hardware
Authors: Schlütter Marc  , Philippen Peter  , Morin Laurent  , Geimer Markus  , Mohr Bernd
Published: February 2025

In heterogeneous environments with multi-core systems and accelerators, programming and optimizing large parallel applications turns into a time-intensive and hardware-dependent challenge. To assist application developers in this process, a number of tools and high-level compilers have been developed. Directive-based programming models such as HMPP and OpenACC provide abstractions over low-level GPU programming models,such as CUDA or OpenCL. The compilers developed by CAPS automatically transform the pragma-annotated application code into low-level code, thereby allowing the parallelization and optimization for a given accelerator hardware. To analyze the performance of parallel applications, multiple partners in Germany and the US jointly develop the community measurement infrastructure Score-P. Score-P gathers performance execution profiles, which can be presented and analyzed within the CUBE result browser, and collects detailed event traces to be processed by post-mortem analysis tools such as Scalasca and Vampir.
Programming in Paragon
Authors: van Delft Bart  , Broberg Niklas  , Sands David
Published: February 2025

This tutorial provides an introduction to Paragon, a programming language that allows specification of security concerns on the data that is manipulated, as an integral part of the code. The target audience are programmers, as the end users of the programming language. The goal of the tutorial is to learn how to write information-flow secure programs in Paragon, without prior knowledge of theories, enforcement mechanisms and meta-properties underlying the field of information flow research.
On Risk-Averse Weighted k-Club Problems
Authors: Rysz Maciej  , Mahdavi Pajouh Foad  , Krokhmal Pavlo  , Pasiliao Eduardo
Published: February 2025

In this work, we consider a risk-averse maximum weighted k-club problems. It is assumed that vertices of the graph have stochastic weights whose joint distribution is known. The goal is to find the k-club of minimum risk contained in the graph. A stochastic programming framework that is based on the formalism of coherent risk measures is used to find the corresponding subgraphs. The selected representation of risk of a subgraph ensures that the optimal solutions are maximal k-clubs. A combinatorial branch-and-bound solution algorithm is proposed and solution performances are compared with an equivalent mathematical programming counterpart problem for instances with k = 2.
Security in Wireless Networks: A Tutorial
Authors: Vadlamani Satish  , Medal Hugh  , Ekşioğlu Burak
Published: February 2025

The open nature of wireless networks makes them vulnerable to attacks by external or internal users of the network. Wireless networks have applications in military, disaster and commercial areas. It is important to find ways to defend against such attacks. While there are many studies dealing with different types of attacks and defense strategies, there are no tutorials available in literature that introduces the security issues in wireless networks to an operations research audience. In this paper we provide an introduction to the different attacks and defense strategies in wireless networks. We also discuss modeling constructs and give several modeling examples aimed to help new researchers become acquainted with this area of research.
Evidence on the need of housing renovation in the next decades
Authors: Shiue Ivy
Published: February 2025

Housing inequalities have posed significant social and health problems in every society. Sick building syndrome has been known to be related to human health. However, the role of housing age, which is related to construction materials and duration maintenance, has not been explored. Therefore, we aimed to determine the relationship of housing built year and individual health and wellbeing in a national and population-based setting. Data were retrieved from United States National Health and Nutrition Examination Surveys, 2009–2010 including demographics, housing characteristics, self-reported health status, biomarkers, and urinary environmental chemical concentrations. Adults aged 20 and above were included for statistical analysis. Analysis involved chi-square test, t-test, and survey-weighted logistic regression modelling. People who resided in housing built before 1990 had higher risks of high blood pressure, asthma, chronic bronchitis, liver problems, emphysema, and cardiovascular disease including stroke, heart failure, angina, and heart attack. Higher values in C-reactive protein, blood lead, blood cadmium, and positive hepatitis B, C, and E antibodies responses and environmental chemical concentrations were observed as well. People who reported an older housing age also reported poorer health outcomes including cardiovascular and respiratory health problems and abnormal values in certain biomarkers. A health and housing policy on housing renovation to improve health and wellbeing of occupants in a more sustainable in the coming decades might need to be considered.
The web as a site of intractable governance
Authors: Giannoumis G. Anthony
Published: February 2025

To what extent does the demand and development of online anonymity interact with efforts to achieve universal design and preserve copyright protections? Based on original research, currently in progress, this article establishes a rational choice model for policy actors involved in the adoption of online anonymity technology. The analysis then compares the model to qualitative data collected from a document analysis of media and government publications and quantitative data on web search trends. The results demonstrate the importance of a universal design approach to web content, the limitations of current legislative approaches to accessibility, and the unintended effects of intellectual property laws. The paper concludes by identifying opportunities for extending the empirical examination of the web as a site of intractable governance.
Challenges and Opportunities for Inclusive Design in Graduate Architecture
Authors: Tauke Beth  , Steinfeld Edward  , Basnak Megan
Published: February 2025

Inclusive Design is one of the most important design movements of this era; as demographics change throughout the world, it promises to gain increasing significance. Despite this global trend, architecture programs in U.S. universities have been slow to incorporate inclusive design into curricula. The State University of New York at Buffalo is an exception, and has offered a formal Master of Architecture – Inclusive Design since 2006. This paper describes obstacles to starting UD graduate programs, challenges and successes of the Buffalo program, and recommendations for ways to grow additional UD programs in architecture.
A Tangible Interface for Information Exchange Addressing Deaf-Blind Users
Authors: Bieling Tom  , Martins Tiago  , Joost Gesche
Published: February 2025

The LormHand is a public installation allowing deaf-blind individuals to post messages on Twitter or other social networks. This is achieved by means of a tangible interface in the shape of a hand, designed to recognize the tactile patterns of the Lorm Alphabet. It was originally developed for a deaf-blind protest march in Berlin and addresses the condition of isolation imparted by deaf-blindness.
Challenges with assistive technology compatibility in universal design
Authors: Fuglerud Kristin Skeide  , Halbach Till  , Skotkjerra Stein Erik
Published: February 2025

Compatibility with assistive technology (AT) such as screen readers is a precondition for universal design of ICT. This is also a requirement in the W3C WCAG guidelines. Experience shows that providing compatibility with one screen reader does not necessarily ensure compatibility with other screen readers from different vendors. It is therefore necessary to test an ICT solution with different AT from different vendors to ensure accessibility for all AT users. In this work, we investigate compatibility challenges with AT in depth and explore the potential for an online tool for AT compatibility testing.
Experimental Measurements and Simulations of ECT Signal for Ferromagnetic SG Tubes Covered by a Sodium Layer
Authors: Yamaguchi Toshihiko  , Mihalache Ovidiu  , Ueda Masashi
Published: February 2025

This paper presents experimental measurements and 3D finite element simulations of the In-Service Inspection (ISI) of ferromagnetic steam generator (SG) tubes covered by a sodium layer. The ISI of SG tubes is using remote field eddy current technique (RF-ECT) and detect defects located near or between tube support plates and SG tube. Large scale electromagnetic eddy current computations are performed using parallel simulations with up to 1024 CPUs on Fujitsu BX900 based on in-house developed/parallelized code 3D-RFECT. Validations of FEM simulations with experimental measurements for helical tubes are conducted for a large model of SG tubes support plate and three SG tubes attached to it.
Numerical Simulation of EMAT Signals for Detection of Debonding in HIP Welding of Multilayer Tubes
Authors: Zhou Haiqiang  , Li Yong  , Chen Zhenmao
Published: February 2025

Divertor, one of the most challenging in-vessel components facing to plasma in a Tokamak device, is composed of tungsten or carbon fiber composites (CFC) mono-block of multilayer tube structure to withstand huge heat and particle flux. The multilayer tube bonded with hot isostatic pressing (HIP) welding technology is one of the key components for removing heat in divertor. The debonding defect in HIP welding surface may occurs due to fabrication and heat fatigue reason and may significantly reduce the heat transfer ability of the tubes. The debonding defect needs to be inspected in a nondestructive way to prevent local over heat and structural failure. In this paper, two kinds of EMAT probes are proposed to detect debonding defect in the multilayer tubes and their validity is valuated numerically by using a simulation code based on the formulation of reduce vector potential (Ar) method and the time domain difference scheme for wave propagation simulation.
Development of Automated Tube Deposit Measurement System For Steam Generator Tubing of Nuclear Power Plant
Authors: Kim Min-Kyoung  , Jung Nam-Du  , Yim Chang-Jae  , Park Young-Woo
Published: February 2025

As operating time of nuclear power plants increase, corrosion products in secondary water are built up as scaled deposits on the outside of steam generator tubes, increasing potentials for the corrosion of tube materials with fluid flow restrictions and heat transfer efficiency problems. Several experiences in nuclear power plants have shown that the heat fouling by corrosion product formations in secondary side cause water level oscillation, degrading the thermal performance of steam generators. It is necessary to assess the extent and location of scaled deposits on steam generator tubes for the effective management and maintenance of steam generator. In prior work, tube mock-ups with various thicknesses of scaled deposits have been set up to provide information about the overall deposit condition of steam generator tubes, deriving methodologies to automatically measure deposit thicknesses [1]. In this paper, another tube mock-up with different deposit simulation method is used to improve the similarity in deposit densities of field data and eddy current signal behaviors from the new tube mock-up are correlated to the deposit thicknesses. Using the correlation as a reference, the automatic scaled deposit measurement system has been developed with 3 dimensional mappings of deposit distributions and the overall estimation of the scaled deposit amount. The developed system has been applied to actual plant data of 2 outages and showed similarities with heat transfer distributions of steam generators. Historical comparisons of 2 outage data revealed actual increase of deposit formations and provided useful information as an analysis tool for steam generator deposit formation monitoring and maintenance.
Biomaterial Real Defects Evaluation Using Advanced Detection Sensors
Authors: Pernisova Viera  , Capova Klara  , Smetana Milan  , Strapacova Tatiana
Published: February 2025

The paper deals with biomaterial electromagnetic non-destructive testing with an emphasis on real defects identification. Various modifications of eddy current testing (ECT) detection sensors will be compared and discussed from the desired detected signal characteristics points of view. Advanced magnetic sensors such as giant magneto-resistance (GMR) sensors and fluxgate sensors and probe coils are presented in the paper. These advanced sensors are characterized by their sensitivity, frequency range and sensors dimensions. The measurements for detection of stress corrosion cracks (SCC) in implants materials using magnetic sensors will be presented and their responses will be compared.
High Frequency Eddy-Current and Induction Thermography Inspection Techniques for Turbine Components
Authors: Frąckowiak Wojciech  , Bruchwald Oliver  , Reimche Wilfried  , Bach Friedrich-Wilhelm  , Jürgen Maier Hans
Published: February 2025

Conventional non-destructive eddy-current testing and induction-based thermographic techniques do not allow for the characterization and evaluation of a turbine blade's substrate material and the thin corrosion protective layer (20...50 μm) separately, because of the low electrical conductivity of 0.5–1.5 MS/m and the relatively large eddy-current penetration depth at standard testing frequencies. Using testing frequencies in the megahertz range limits the inductively excited volume to the near-subsurface region and enables the layer and substrate materials to be individually studied. Within the Collaborative Research Centre 871, novel high frequency, non-destructive eddy-current and induction thermography inspection techniques are being developed and used for material characterization and damage detection in turbine blades [1], [2]. Experiments were carried out using high-pressure turbine blades of the first and second stage made of René 142 and PWA 1426 with metallic PtAl-, MCrAlY-, and ceramic (YSZ) thermal barrier coatings. The high-frequency eddy-current inspection technology with test frequencies in the megahertz range up to 100 MHz reduces the standard penetration depth to less than 50 μm. This allows for the detection of local damages and defects, as well as the characterization of the materials' condition separately from the substrate material with emphasis on the condition of the thin PtAl- and MCrAlY-coatings. Delamination and chemical changes in the coating such as oxidation or sulfidation lead to altered local electrical conductivities and magnetic properties and can be identified by using high frequency, eddy-current testing techniques while the lift-off effect is simultaneously used to measure the thermal barrier's coating thickness. The high frequency induction thermography inspection technology with pulsed excitation up to 3 MHz focuses on fast and sensitive detection of the surface and near subsurface damages in the turbine blade's coating and the substrate material. The relevant surface defects are distinguished from other microstructural imperfections as well as from changes of infrared spectral emissivity due to surface impurities and geometric effects by using a series of sequential excitation pulses followed by a pixel-wise analysis of the thermal response in the component with respect to the excitation. With this multiscale approach the inspection time and resolution can be varied by using exchangeable infrared optics with various focal lengths. Global component inspection can be achieved with a wide angle lens, which is suitable for fast detection of larger damages (>1 mm2) such as cracks, chipping, spalling and delamination of the coating. The evaluation of micro-damage occurs subsequently on a local scale with a higher resolution macro lens scan and a resolution of up to 15 μm/px, but longer measurement time per surface area.
Low Level Data Fusion of NDT Methods Results for Inspection of Stress Subjected Composite Materials
Authors: Psuj Grzegorz  , Baniukiewicz Piotr  , Lopato Przemyslaw  , Szymanik Barbara  , Chady Tomasz
Published: February 2025

In this paper the inspection of stress subjected composite materials was carried out using three nondestructive methods: radiography, infrared thermography and terahertz. In order to combine the information about the defects arising in examined materials the low-level data fusion algorithms were applied. The results are presented and discussed.
Barkhausen Noise Testing of Residual Stresses Introduced by Surface Hardening Techniques
Authors: Stupakov Oleksandr  , Takagi Toshiyuki  , Kolařík Kamil
Published: February 2025

Several industrial steels were ground and shot peened. X-ray diffraction measurements were performed for accurate determination of the surface residual stresses. Magnetic Barkhausen noise method was tested for applicability to determine these stresses as well. A modified attached probe with a Hall sensor array for accurate measurement of the surface magnetic field was used. Good linear correlations between the Barkhausen noise parameters and the residual stresses measured by the X-ray diffraction technique were obtained.
Evaluation of Wall Thinning in Carbon Steel Piping Based on Magnetic Saturation Pulsed Eddy Current Testing Method
Authors: Xie Shejuan  , Chen Zhenmao  , Zhou Haiqiang  , Cai Wenlu  , Takagi Toshiyuki  , Uchimoto Tetsuya  , Dobmann Gerd
Published: February 2025

Quantitative non-destructive evaluation of wall thinning in carbon steel piping is a difficult and urgent issue for safety of nuclear power plants. In this study, a magnetic saturation PECT (pulsed eddy current testing) method is proposed for this purpose, where a magnetic yoke is utilized to generate strong static magnetic field to saturate the piping material and to increase the skin depth, and the PECT is applied then in the magnetic saturation environment. The feasibility of the magnetic saturation PECT method for wall thinning detection in carbon steel piping is validated through numerical simulations. Firstly, the simulated polarization approach is adopted for the calculation of the static magnetic field distribution generated by the electromagnetic magnet, then the material permeability distribution is predicted according to the B-H curve of the targeted material. Finally the efficient PECT forward simulation tool is updated for the carbon steel based on the Ar(reduced A) method and the Fourier series strategy to validate the wall thinning detection in carbon steel material.
Electromagnetic Metamaterial Sensors for Structural Health Monitoring
Authors: Grimberg Raimond  , Tian Gui-Yun  , Savin Adriana  , Steigmann Rozina  , Dobrescu Gabriel Silviu
Published: February 2025

The monitoring of large structures typically require a variety of sensors based on different physical principles combined with set an appropriate set of diagnosis and prognosis methods. The monitoring is in tightly coupled aspect of nondestructive examination. This paper presents a new type of passive wireless sensors for monitoring of strain-stress. The sensor employs a special type of metamaterial named split ring resonator. In order to increase the sensitivity and the tuning of the desired interrogation frequency, the sensor use a self-assembled layer-by-layer single wall carbon nanotubes/graphene as well as an RFID tag. The key essential element for the wireless sensors, can be realized using a split ring resonator.
Three-Dimensional Reconstruction of Partially Conductive Cracks from ECT Response Signals
Authors: Janousek Ladislav  , Rebican Mihai  , Smetana Milan  , Strapacova Tatiana  , Duca Anton
Published: February 2025

This paper presents a novel approach for diagnosis of real cracks from two-dimensional eddy current testing signals by means of a stochastic method, such as tabu search. A new testing probe driving uniformly distributed eddy currents is employed for the inspection. Three spatial components of the perturbation field due to partially conductive cracks are sensed as the response signals in order to enhance information level of the inspection. The signals are simulated by a fast forward FEM-BEM solver using a database. Two crack models are proposed for the inversion: a crack with cuboid shape and a crack with more complex shape. In the both cases, the cracks have uniform conductivity. The length, depth, width and conductivity of the crack are unknown in the inversion process. Numerical results of the 3D reconstruction of partially conductive cracks from simulated 2D signals with added noise are presented and discussed.
Using Tikhonov Regularization to Determine the Eddy Current Density in a Plate
Authors: Ribeiro A. Lopes  , Pasadas Dário J.  , Ramos Helena G.  , Rocha Tiago J.
Published: February 2025

In this paper we present a method to determine the current density inside an aluminum plate. The general idea consists in generating eddy currents in the plate which, in the case of flawless material, must be of uniform density, pointing along a pre-defined direction inside a given area on the plate surface. These currents are produced using a plane coil with parallel circuit lines capable of producing a spatially constant excitation magnetic field inside a given area. Using this method the aluminum plate senses an excitation field that is invariant under limited translations. A giant magneto-resistor shall measure the magnetic field perturbations originated by material inhomogeneity. From this field the eddy currents are determined using Tikhonov regularized inversion.
Pulsed Eddy Current Technique for Testing of Stainless Steel Plates
Authors: Rao K. Sambasiva  , Jayakumar T.  , Sekhar A. Chandra  , Rao B. Purnachandra
Published: February 2025

Pulsed eddy current (PEC) technique is attractive for detection of surface defects and wall-thinning in covered electrically conductive materials. This paper discusses development of PEC technique and two different types of self-nulling probes (differential Hall sensors and Double-D differential coils) for detection of surface notches in a thick stainless steel plate. PEC testing of covered objects is attempted. In this regard, the influence of lift-off on the PEC signal due to insulation shims and thin aluminum layer is studied using the peak amplitude and the performance of the two probes is compared. The results showed that the PEC instrument, probes and scanner developed can be used for detection as well as imaging of defects in stainless steel plates covered with insulation.