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Moving is the key to modern life. Most things are in moving such as vehicles and user mobiles, so the need for high-speed wireless networks to serve the high demand of the wireless application becomes essential for any wireless network design. The use of web browsing, online gaming, and on-time data exchange like video calls as an example means that users need a high data rate and fewer error communication links. To satisfy this, increasing the bandwidth available for each network will enhance the throughput of the communication, but the bandwidth available is a limited resource which means that thinking about techniques to be used to increase the throughput of the network is very important. One of the techniques used is the spectrum sharing between the available networks, but the problem here is when there is no available channel to connect with. This encourages researchers to think about using scheduling as a technique to serve the high capacity on the network. Studying scheduling techniques depends on the Quality-of-Service (QoS) of the network, so the throughput performance is the metric of this paper. In this paper, an improved Best-CQI scheduling algorithm is proposed to enhance the throughput of the network. The proposed algorithm was compared with three user scheduling algorithms to evaluate the throughput performance which are Round Robin (RR), Proportional Fair (PF), and Best-CQI algorithms. The study is performed under Line-of-Sight (LoS) link at carrier frequency 2.6 GHz to satisfy the Vehicular Long Term Evolution (LTE-V) with the high-speed scenario. The simulation results show that the proposed algorithm outperforms the throughput performance of the other algorithms.

Funding Information: The research was funded by The Finnish Research Programme on Nuclear Power Plant Safety 2019 – 2022 (SAFIR-2022). Funding Information: The flawed and unflawed mock-ups for this study were provided by SQC, EPRI and PNNL. The manufacturing of additional flaws and eFlaw data manipulation was provided by Trueflaw. These contributions are gratefully acknowledged. The research was funded by The Finnish Research Programme on Nuclear Power Plant Safety 2019 ? 2022 (SAFIR-2022). Publisher Copyright: © 2021 The Author(s) Round robin exercises have traditionally been difficult to arrange in the field of non-destructive testing (NDT). To create a representative round robin exercise, representative mock-ups with representative flaws are needed. The mock-ups are costly and transporting them around the world to facilitate testing by numerous laboratories is difficult. The few round robins that have been completed have often contributed significantly to our understanding on the capability of the used NDT methods and procedures. Recently, the increased use of automated inspections together with the development of virtual flaws (independently by Trueflaw and EPRI) has enabled a new type of round robin, where instead of moving samples around the world, the round robin is focused on the data analysis and only pre-acquired data files are distributed. This makes conducting a round robin much more cost-effective both in terms of arrangement and in terms of inspection effort from the participating companies. In addition, the virtual flaw technology allows unprecedented number and variety of flaws to be included. With high number of flaws included, the results present statistically meaningful sample and can be further analyzed to estimate the probability of detection (POD) with standard statistical tools. In connection with the international project “PIONIC”, such a virtual round robin was arranged for the first time. The exercise showed, that virtual flaws and virtual round robins can be used to extract important information about NDT reliability and performance. Also, some points of development were identified for further studies: the sizing and detection files should be better optimized for their respective uses and the data could be further obfuscated to avoid any possibility of inspectors learning to recognize repeating signal patterns. 12 inspectors submitted results to the virtual round robin. The results showed a90/95 ranging from 1.2 to 7.0 mm – a significant variation in performance. The difference was mainly attributed to different inspection strategies. In addition, an unexplained tendency to miss big cracks was noted on some result sets. One of the data files did not contain any flaws. None of the inspectors correctly identified the file as flawless.

As ever-increasing amounts of renewable electricity enter the energy supply mix on a regional, national and international basis, greater emphasis is being placed on energy conversion and storage technologies to deal with the oscillations, excess and lack of electricity. Hydrogen generation via proton exchange membrane water electrolysis (PEMWE) is one technology that offers a pathway to store large amounts of electricity in the form of hydrogen. The challenges to widespread adoption of PEM water electrolyzers lie in their high capital and operating costs which both need to be reduced through R&D. An evaluation of reported PEMWE performance data in the literature reveals that there are excessive variations of in situ performance results that make it difficult to draw conclusions on the pathway forward to performance optimization and future R&D directions. To enable the meaningful comparison of in situ performance evaluation across laboratories there is an obvious need for standardization of materials and testing protocols. Herein, we address this need by reporting the results of a round robin test effort conducted at the laboratories of five contributors to the IEA Electrolysis Annex 30. For this effort a method and equipment framework were first developed and then verified with respect to its feasibility for measuring water electrolysis performance accurately across the various laboratories. The effort utilized identical sets of test articles, materials, and test cells, and employed a set of shared test protocols. It further defined a minimum skeleton of requirements for the test station equipment. The maximum observed deviation between laboratories at 1 A cm−2 at cell temperatures of 60 °C and 80 °C was 27 and 20 mV, respectively. The deviation of the results from laboratory to laboratory was 2–3 times higher than the lowest deviation observed at one single lab and test station. However, the highest deviations observed were one-tenth of those extracted by a literature survey on similar material sets. The work endorses the urgent need to identify one or more reference sets of materials in addition to the method and equipment framework introduced here, to enable accurate comparison of results across the entire community. The results further imply that cell temperature control appears to be the most significant source of deviation between results, and that care must be taken with respect to break-in conditions and cell electrical connections for meaningful performance data.

With this external quality assessment (EQA) scheme, we aim to investigate the diagnostic performance of the currently available methods for the detection of ALK alterations in non-small cell lung cancer on a national scale, namely, in situ hybridization (ISH), immunohistochemistry (IHC), and RNA/DNA sequencing (NGS). The EQA scheme cohort consisted of ten specimens, including four ALK positive and six ALK negative samples, which were thoroughly pretested using IHC, ISH, and RNA/DNA NGS. Unstained tumor sections were provided to the 57 participants, and the results were retrieved via an online questionnaire. ISH was used by 29, IHC by 38, and RNA/DNA sequencing by 19 participants. Twenty-eight institutions (97%) passed the ring trial using ISH, 33 (87%) by using IHC, and 18 (95%) by using NGS. The highest sensitivity and interrater agreement (Fleiss ‘ kappa) was observed for RNA/DNA sequencing (99%, 0.975), followed by ISH (94%, 0.898) and IHC (92%, 0.888). However, the proportion of samples that were not evaluable due to bad tissue quality was also higher for RNA/DNA sequencing (4%) compared with ISH (0.7%) and IHC (0.5%). While all three methods produced reliable results between the different institutions, the highest sensitivity and concordance were observed for RNA/DNA sequencing. These findings encourage the broad implementation of this method in routine diagnostic, although the application might be limited by technical capacity, economical restrictions, and tissue quality of formalin-fixed samples. Supplementary Information The online version contains supplementary material available at 10.1007/s00428-021-03106-5.

Cloud computing has emerged as the primary choice for developers in developing applications that require high-performance computing. Virtualization technology has helped in the distribution of resources to multiple users. Increased use of cloud infrastructure has led to the challenge of developing a load balancing mechanism to provide optimized use of resources and better performance. Round robin and least connections load balancing algorithms have been developed to allocate user requests across a cluster of servers in the cloud in a time-bound manner. In this paper, we have applied the round robin and least connections approach of load balancing to HAProxy, virtual machine clusters and web servers. The experimental results are visualized and summarized using Apache Jmeter and a further comparative study of round robin and least connections is also depicted. Experimental setup and results show that the round robin algorithm performs better as compared to the least connections algorithm in all measuring parameters of load balancer in this paper.

Cloud computing is a ubiquitous network access model to a shared pool of configurable computing resources where available resources must be checked and scheduled using an efficient task scheduler to be assigned to clients. Most of the existing task schedulers, did not achieve the required standards and requirements as some of them only concentrated on waiting time or response time reduction or even both neglecting the starved processes at all. In this paper, we propose a novel hybrid task scheduling algorithm named (SRDQ) combining Shortest-Job-First (SJF) and Round Robin (RR) schedulers considering a dynamic variable task quantum. The proposed algorithms mainly relies on two basic keys the first having a dynamic task quantum to balance waiting time between short and long tasks while the second involves splitting the ready queue into two sub-queues, Q1 for the short tasks and the other for the long ones. Assigning tasks to resources from Q1 or Q2 are done mutually two tasks from Q1 and one task from Q2. For evaluation purpose, three different datasets were utilized during the algorithm simulation conducted using CloudSim environment toolkit 3.0.3 against three different scheduling algorithms SJF, RR and Time Slice Priority Based RR (TSPBRR) Experimentations results and tests indicated the superiority of the proposed algorithm over the state of art in reducing waiting time, response time and partially the starvation of long tasks.

We study Age of Information (AoI) in a random access channel where a number of devices try to send status updates over a common medium. Assuming a time-slotted scenario where multiple transmissions result in collision, we propose a threshold-based lazy version of Slotted ALOHA and derive the time average AoI achieved by this policy. We demonstrate that the average AoI performance of the lazy policy is significantly better than Slotted ALOHA, and close to the ideal round robin benchmark. This work was funded in part by Huawei and by TUBITAK Grant 117E215. Publisher's Version

Powder metallurgy processes rely on powder flowability. However, flowability is not an intrinsic property and depends on the measurement conditions. Standards have been developed to adjust measurement methods to various flow conditions but there is presently questions whether current methods are adapted to the specific requirements of powder bed additive manufacturing. Rheology has been used to assess powder flowability but there is still limited information available on the robustness of the method. This paper presents the flow characteristics measured in five laboratories with a powder rheometer. Attempts were made to understand the sources of intra and inter laboratory variations and find ways to reduce them. The variations do not seem to be associated with sampling or environmental conditions. Experimental setup, calibration and/or the modification of the powder during handling could be associated with the variations observed. However, additional tests would be required to confirm the sources and improve the repeatability of the measurements.

Cloud Computing and Big Data are the upcoming Information Technology (IT) computing models. These groundbreaking paradigms are leading IT to a new set of rules that aims to change computing resources delivery and exploitation model, thus creating a novel business market that is exponentially growing and attracting more and more investments from both providers and end users that are looking forward to make profits from these innovative models of computing. In the same context, researchers and investigators are wrestling time in order to develop, test and optimize Cloud Computing and Big Data platforms, whereas several studies are ongoing to determine and enhance the essential aspects of these computing models especially compute resources allocation. The processing power scheduling is crucial when it comes to Cloud Computing and Big Data because of the data growth management and delivery design proposed by these new computing models, that requires faster responses from platforms and applications. Hence originates the importance of developing high efficient scheduling algorithms that are compliant with these computing models platforms and infrastructures requirement., Cloud Computing et Big Data sont les prochains modèles informatiques. Ces paradigmes révolutionnaires conduisent l'informatique à un nouveau jeu de règles qui vise à changer la livraison des ressources informatiques et le modèle d'exploitation, créant ainsi un monde d'affaires nouveau qui croît de façon exponentielle et attire de plus en plus d'investissements des fournisseurs et des utilisateurs finaux qui attendent Amener profit de ces modèles innovants de l'informatique. Dans le même contexte, les chercheurs combattent pour développer, tester et optimiser les plates-formes Cloud Computing et Big Data, alors que plusieurs études sont en cours pour déterminer et améliorer les aspects essentiels de ces modèles informatiques, en particulier l'allocation des ressources. La planification de la puissance de traitement est cruciale quand il s'agit de Cloud Computing et Big Data en raison de la gestion de la croissance des données et la conception de livraison proposée par ces nouveaux modèles informatiques, qui nécessite des réponses plus rapides des plates-formes et des applications. D'où l'origine de l'importance de développer des algorithmes d'ordonnancement efficaces qui sont conformes à ces plates-formes de modèles informatiques et aux exigences d'infrastructure.

Journal of synchrotron radiation 25(4), 935 - 943 (2018). doi:10.1107/S1600577518003752, Round robin studies have been used across fields of science for quality control testing and to investigate laboratory dependencies and cross-platform inconsistencies as well as to drive forward the improvement of understanding of experimental systems, systematic effects and theoretical limitations. Here, following the Q2XAFS Workshop and Satellite to IUCr Congress 2017 on `Data Acquisition, Treatment, Storage – quality assurance in XAFS spectroscopy', a mechanism is suggested for a suitable study across XAFS (X-ray absorption fine-structure) beamlines and facilities, to enable each beamline to cross-calibrate, provide representative test data, and to enable collaborative cross-facility activities to be more productive., Published by Wiley-Blackwell, [S.l.]

Round Robin based Intermittent Periodic Transmit (RR-IPT) has been proposed which achieves highly efficient multi-hop relays in multi-hop wireless backhaul networks (MWBN) where relay nodes are 2-dimensionally deployed. This paper newly investigates multi-channel packet scheduling and forwarding scheme for RR-IPT. Downlink traffic is forwarded by RR-IPT via one of the channels, while uplink traffic and part of downlink are accommodated in the other channel. By comparing IPT and carrier sense multiple access with collision avoidance (CSMA/CA) for uplink/downlink packet forwarding channel, IPT is more effective in reducing packet loss rate whereas CSMA/CA is better in terms of system throughput and packet delay improvement.

This study addresses the issue of poor intercomparability of measurements of organic photovoltaic (OPV) devices among different laboratories. We present a round robin performance testing of novel OPV devices among 16 laboratories, organized within the framework of European Research Infrastructure Project (SOPHIA) and European Energy Research Alliance (EERA). Three types of OPVs with different structures, dimensions and encapsulations are studied and compared with reference Si solar cells certified by accredited laboratories. The agreement of the measurements of these among different laboratories is analyzed by focusing on testing procedures, testing equipment and sample designs. A number of deviations and pitfalls are revealed and based on the analyses, a set of recommendations are suggested for improving the agreement among the measurements of such OPV technologies. European Commission's FP7 programme; European Energy Research Alliance (EERA); EUDP; UK Department for Business, Innovation and Skills

A round robin for parabolic trough receiver heat loss and optical efficiency in the laboratory was performed between five institutions using five receivers in 2015/2016. Heat loss testing was performed at three cartridge heater test benches and one Joule heating test bench in the temperature range between 100 °C and 550 °C. Optical efficiency testing was performed with two spectrometric test bench and one calorimetric test bench. Heat loss testing results showed standard deviations at the order of 6% to 12 % for most temperatures and receivers and a standard deviation of 17 % for one receiver at 100 °C. Optical efficiency is presented normalized for laboratories showing standard deviations of 0.3 % to 1.3 % depending on the receiver. © 2017 Author(s).

This paper proposes a software and hardware solution for real time condition monitoring applications. The proposed device, called XpertTrack, exchanges data through the GPRS protocol over a GSM network and monitories temperature and vibrations of critical merchandise during commercial shipments anywhere on the globe. Another feature of this real time tracker is to provide GPS and GSM positioning with a precision of 10 m or less. In order to interpret the condition of the merchandise, the data acquisition, analysis and visualization are done with 0.1 °C accuracy for the temperature sensor, and 10 levels of shock sensitivity for the acceleration sensor. In addition to this, the architecture allows increasing the number and the types of sensors, so that companies can use this flexible solution to monitor a large percentage of their fleet.

Accurate characterization and reporting of organic photovoltaic (OPV) device performance remains one of the important challenges in the field. The large spread among the efficiencies of devices with the same structure reported by different groups is significantly caused by different procedures and equipment used during testing. The presented article addresses this issue by offering a new method of device testing using >suitcase sample> approach combined with outdoor testing that limits the diversity of the equipment, and a strict measurement protocol. A round robin outdoor characterization of roll-to-roll coated OPV cells and modules conducted among 46 laboratories worldwide is presented, where the samples and the testing equipment were integrated in a compact suitcase that served both as a sample transportation tool and as a holder and test equipment during testing. In addition, an internet based coordination was used via plasticphotovoltaics.org that allowed fast and efficient communication among participants and provided a controlled reporting format for the results that eased the analysis of the data. The reported deviations among the laboratories were limited to 5% when compared to the Si reference device integrated in the suitcase and were up to 8% when calculated using the local irradiance data. Therefore, this method offers a fast, cheap and efficient tool for sample sharing and testing that allows conducting outdoor measurements of OPV devices in a reproducible manner., This work has been supported by the EUDP (j.no. 64012-0202), the Danish National Research Foundation, the Eurotech Universities Alliance project “Interface science for photovoltaics (ISPV)”, the European Research Infrastructure (SOPHIA), the European Energy Research Alliance (EERA), the Danish Ministry of Science, Innovation and Higher Education under a Sapere Aude Top Scientist Grant no.( DFF – 1335-00037A), an Elite Scientist Grant no.( 11-116028), MICINN-Spain(Grant # MAT2010-21267-C02-02) including FEDER funds, the UK Department for Business, Innovation & Skills, the Royal Society and the EPSRC for grants EP/G031088, EP/J500021 and EP/K030671. MN and SAC acknowledge co-funding by the European Regional Development Fund and the Republic of Cyprus through the Research Promotion Foundation (Strategic Infrastructure Project ΝΕΑ ΥΠΟΔΟΜΗ/ΣΤΡΑΤΗ/0308/06). A. E. G., R. K. M. and E.A.K. thank a financial support from the European Commission׳s Seventh Framework Program under Grant agreement no. 261936.

Background Interferon-beta (IFNB) therapy for multiple sclerosis can lead to the induction of neutralizing antibodies (NAbs) against IFNB. Various methods are used for detection and quantification of NAbs. Methods Blood samples from 125 IFNB-1b–treated patients, which were tested NAb negative or NAb positive after conclusion of a clinical study, were retested three years after first being assessed in four different laboratories that offer routine NAb testing to practicing neurologists. The myxovirus protein A (MxA) induction assay, the cytopathic effect (CPE) assay (two laboratories), or the luciferase assay were used. Intra- and inter-laboratory agreement between assays with respect to NAb detection and NAb titer quantification were evaluated. Results High agreement for NAb detection (kappa coefficient, 0.86) and for titer levels was observed for the intra-laboratory comparison in the laboratory using the MxA induction assay performed three years ago and now. A similarly high agreement for NAb detection (kappa coefficient, 0.87) and for titer quantification was noted for the MxA assay of this laboratory with one of two laboratories using the CPE assay. All other inter-laboratory comparisons showed kappa values between 0.57 and 0.68 and remarkable differences in individual titer levels. Conclusions There are considerable differences in the detection and quantification of IFNB-induced NAbs among laboratories offering NAb testing for clinical practice using different assay methods. It is important that these differences are considered when interpreting NAb results for clinical decision-making and when developing general recommendations for potentially clinically meaningful NAb titer levels.

In this paper, we propose a multi-level round-robin multicast scheduling (MLRRMS) algorithm with look-ahead (LA) mechanism for N×N input-queued switches. Fan-out splitting is applied, where a multicast cell can be transferred to all its destinations over any number of cell times. The scheduler constructs the Traffic Matrix before each cell transmission based on the fan-out vectors of the cells in the queues. A scheduling pointer independently moves on each column of the Traffic Matrix in a round-robin fashion and returns the decision to the Decision Matrix. The sync procedure is carried out to reduce the unnecessary transmissions of a cell. The look-ahead mechanism is executed to reduce the head-of-line blocking problem resulting in increased the throughput and reduced cell delay.

19 páginas, 16 figuras, 16 tablas.-- El pdf del artículo es la versión pre-print.-- Trabajo presentado al "3rd International Summit on OPV Stability".-- et al., A large number of flexible polymer solar modules comprising 16 serially connected individual cells was prepared at the experimental workshop at Risø DTU. The photoactive layer was prepared from several varieties of P3HT (Merck, Plextronics, BASF and Risø DTU) and two varieties of ZnO (nanoparticulate, thin film) were employed as electron transport layers. The devices were all tested at Risø DTU and the functional devices were subjected to an inter-laboratory study involving the performance and the stability of modules over time in the dark, under light soaking and outdoor conditions. 24 laboratories from 10 countries and across four different continents were involved in the studies. The reported results allowed for analysis of the variability between different groups in performing lifetime studies as well as performing a comparison of different testing procedures. These studies constitute the first steps toward establishing standard procedures for an OPV lifetime characterization., This work was supported by: the Danish Strategic Research Council (DSF2104-07-0022), EUDP(j.nr.64009-0050), PV-ERA-NET (project acronym POLYSTAR),the Spanish Ministry of Science and Innovation, MICINN for the project ENE2008-04373 and CSIC for the PIE-200860I134. Financial support by the Austrian Research Promotion Agency (FFG), the Christian Doppler Research Association (CDG), the Austrian Federal Ministry of Economy, Family and Youth (BMWFJ) and the ISOVOLTAIC Gmb His gratefully acknowledged. Part of this work was supported by the PCCL(ProjectIV-1.02) with in the frame-work of the COMET-program of the Austrian Government. MH, TM, KL and MR would like to thank the Bundesministerium fuer Bildung und Forschung in the frame works of the InnoProfile project (03IP602), the OPEG project(13N9720) and the OPA project (13N9872). HH gratefully acknowledges funding with in the frame of BMBFOPV program. This work was partially supported by the King Abdullah University of Science and Technology and the Department of Energy, by KIST internal research fund under the Contract no. of 2E21831; by the European Commission as part of the Framework 7ICT2009 collaborative project HIFLEX(Grant Agreement no. 248678). RR, MS&HH acknowledge financial support from German Federal Ministry of Education and Research (BMBF)within‘‘Polymer Photovoltaics Processing’’(PPP) project (support code 13N9843).Part of this work was supported by the Victorian Organic Solar Cell Consortium.

Chemical analysis of ancient residues of pharmaceutical or cosmetic preparations such as balms or ointments is made problematic by the high complexity of these mixtures, composed of organic and inorganic materials. Consequently, a multi-analytical approach and special caution in the interpretation of the results are necessary. In order to contribute to the improvement of analytical strategies for the characterization of complex residues and to reconstruct ancient medical practices, a replica of a pharmaceutical formulation of the seventeenth century was prepared in the laboratory according to a historically documented recipe. In a round robin exercise, a portion of the preparation was analysed as a blind sample by 11 laboratories using various analytical techniques. These included spectroscopic, chromatographic and mass spectrometric methods. None of the laboratories was able to completely reconstruct the complex formulation, but each of them gave partial positive results. The round robin exercise has demonstrated that the application of a multi-analytical approach can permit a complete and reliable reconstruction of the composition. Finally, on the basis of the results, an analytical protocol for the study of residues of ancient medical and pharmaceutical preparations has been outlined. © 2011 Springer-Verlag.

10 páginas, 7 figuras, 6 tablas.-- Trabajo presentado al ICCP-TSOP joint meeting 2008: International conference on coal and organic petrology.-- et al., This paper describes an assessment of char classification system by the Combustion Working Group in Commission III of the International Committee for Coal and Organic Petrology (ICCP). The work of the group culminated in the production of a char atlas after a final round robin exercise. This round robin involved 21 analysts and was an electronic exercise using digitally captured images of individual char particles, rather than actual char blocks. A software program featuring 170 char images was specifically designed to allow operators to identify each char based on a classification system with 9 individual char types; tenuisphere, crassisphere, tenuinetwork, crassinetwork, mixed porous, mixed dense, fusinoid, solid and mineroid. The program electronically recorded all decisions as well as the time taken for each decision to be made. From 170 chars, 128 chars were identified by a majority (> 70%) and these chars were then compiled in a char atlas that is now available for download (www.nottingham.ac.uk/~eczehl/charatlas). As would be expected all analysts appeared to become more confident in identifying chars during the exercise, taking less time per image, but with no clear evidence of improvement. Without exception, analysts took longer to make an incorrect decision.

This paper presents the design and implementation of an efficient sensor network (SN) over standard powerlines. As an application of the proposed SN, a home security and surveillance system was designed and implemented. The SN consists of a array of various types of security and surveillance sensors such as passive infrared motion detectors, glass/window break sensors, chemical/toxic gas sensors and smoke sensors. All the sensors will be connected to a gateway and a control panel through the pre installed powerlines. The gateway communicates with the sensors array using a medium access control (MAC) protocol which is created by combining the common Round Robin MAC and the Stop-and-Wait flow control protocol. The practical experiments conducted on the system have confirmed that the proposed design is robust, efficient and has several advantages over wireless and twistedpair wired sensor networks. The proposed network is implemented using the low-cost TDA5051A powerline modem and the 16F628A peripheral interface controller. 2010 IEEE. Scopus

Quality may be defined as a set of requirements a system should satisfy in order to meet customer’s needs. Control of these requirements assures satisfaction of relevant standards, and consequently the performance levels of a manufacturing/transactional stream. In this context it is fundamental to define control procedures and reliable measurement systems adequate for adopting improvement action as soon as anomalies and dysfunctions are detected. This paper deals with a study of measurement variability occurring during practical exploitation of CMMs (Coordinate Measuring Machines). These measurement systems are designed to probe selected points of workpiece surface, and compare the relevant coordinates or derived quantities with specified values; capability and versatility of CMMs justify their widespread use in industry. Evaluation of CMM measurement variability is however often awkward owing to a number of factors, such as e.g. measurement task, environment, operator and measurement procedures. A round robin exercise involving two industrial laboratories was planned in order to address these issues. Three typical machine tool parts were circulated among participants, who were asked to measure linear dimensions as well as tolerances at specified locations, according to an agreed upon schedule. Results of measurements, performed by experienced CMM industrial users, were analyzed in order to bring out discrepancies, and suggest remedial actions in the light of information gathered. Several factors involving metrological as well as other aspects were observed to cause major discrepancies, yielding in turn information on where to look for potential sources of trouble. Conclusions were drawn in terms of operating procedure, leading to improved information on origin and components of variability.

Today there exist different commercial and proprietary micro-optics measurement instruments for the characterization of micro-optical components and microlenses in particular. However there is often a lack of a complete quantitative optical characterization of the latter components. Therefore we will focus in this paper on the optical characterization of spherical microlenses. Moreover the results of the performed round robin within the European 6th FP Network of Excellence on Micro-optics "NEMO" will allow us to select the most appropriate instrumentation tools for characterizing refractive spherical microlenses.

The round robin "measurement of subwavelength diffractive elements" tackles the metrology problems related to the measurement of diffraction gratings by AFM. It aims at quantifying the absolute precision and the uncertainty of the measurement considering some features of such structures like the depth, the peri od, the fill factor and the shape of the profile. This round robin involved four partners within NEMO. Each partner has measured three different samples: one 2D small depth grating, one 1D small depth grating and one 1D high aspect ratio grating. In order to get rid of the samples inhomogeneity, the measurements were performed exactly at the same location on each sample by all partners. This was achieved by using a multiscale resist pattern transferred on the gratings which precisely defined a 5x5 µm² area. The paper will sum up the experimental values obtained by all the partners, draw general conclusions and make suggestions to improve the ac curacy of AFM measurements. keywords : atomic force microscopy, diffraction grating, metrology, round robin

International audience; In this paper we give an overview of the results obtained after benchmarking instrumentation tools for the characterization of micro-optics within the EC Network of Excellence on Micro-Optics NEMO. After a call within the NEMO network six different partners decided to organize a round robin. In this paper we will give an overview of all the experimental values obtained in the 6 different round robins, then we will comment on these results by explaining the measurement differences and the uncertainties for all measurands.

Lahsen Assoufid, Amparo Rommeveaux, Haruhiko Ohashi, Kazuto Yamauchi, Hidekazu Mimura, Jun Qian, Olivier Hignette, Tetsuya Ishikawa, Christian Morawe, Albert Macrander, Ali Khounsary, and Shunji Goto "Results of x-ray mirror round-robin metrology measurements at the APS, ESRF, and SPring-8 optical metrology laboratories", Proc. SPIE 5921, Advances in Metrology for X-Ray and EUV Optics, 59210J (16 September 2005); https://doi.org/10.1117/12.623209., Optics and Photonics 2005, 2005, San Diego, California, United States, This paper presents the first series of round-robin metrology measurements of x-ray mirrors organized at the Advanced Photon Source (APS) in the USA, the European Synchrotron Radiation Facility in France, and the Super Photon Ring (SPring-8) (in a collaboration with Osaka University,) in Japan. This work is part of the three institutions' three-way agreement to promote a direct exchange of research information and experience amongst their specialists. The purpose of the metrology round robin is to compare the performance and limitations of the instrumentation used at the optical metrology laboratories of these facilities and to set the basis for establishing guidelines and procedures to accurately perform the measurements. The optics used in the measurements were selected to reflect typical, as well as state of the art, in mirror fabrication. The first series of the round robin measurements focuses on flat and cylindrical mirrors with varying sizes and quality. Three mirrors (two flats and one cylinder) were successively measured using long trace profilers. Although the three facilities' LTPs are of different design, the measurements were found to be in excellent agreement. The maximum discrepancy of the rms slope error values is 0.1 μrad, that of the rms shape error was 3 nm, and they all relate to the measurement of the cylindrical mirror. The next round-robin measurements will deal with elliptical and spherical optics.

Cluster systems are leading architectures for building popular Web sites that have to guarantee scalable services when the number of accesses grows exponentially. The most common Web cluster systems consist of replicated back-end and Web servers and a Web switch that routes client requests among the nodes. We propose a new scheduling policy, namely Multi-Class Round Robin (MC-RR) for Web switches operating at layer 7 of the OSI protocol stack. Its goal is to improve load sharing in recent Web clusters that provide multiple services such as static and dynamic information. We demonstrate through a wide set of simulation experiments that other dispatching policies aiming to improve locality in server caches give best results for traditional Web publishing sites providing static information and some simple database searches. On the other hand, when we consider more recent Web sites providing highly dynamic services, MC-RR is much more effective than state-of-the-art Web switch policies. The proposed algorithm has the additional benefit of guaranteeing stable results because its performance does not depend on several parameters that are very hard to tune in highly variable Web systems.

3rd Symposium on Thermo‐Mechanical Fatigue Behavior of Materials, NORFOLK, VA, NOV 04‐05, 1998; International audience; Test blankets of a thermo‐nuclear fusion reactor are subjected during service to alternating thermal and mechanical stresses as a consequence of the pulsed reactor operation. Of particular concern is the thermo‐mechanical fatigue (TMF) endurance of 9% Cr low activation ferrite‐martensite steels. To design such blankets operating under the above loading conditions, for the time being fatigue life is predicted using design codes based on isothermal fatigue material data, but these codes will be verified with TMF data. Within the European Materials Long Term Programme for fusion research several laboratories are involved in performing TMF experiments using different facilities and samples. Results of a TMF‐round robin of four European laboratories will be reported. Comparison of the various test data obtained will give a better understanding for these kinds of tests and enable an in‐depth discussion of the scatter of the results, of its reason and what the implications are in terms of a TMF standard.

In 2011, a round robin test was initiated within the group of CIRP Research Affiliates. The aim was to establish a platform for linking interdisciplinary research in order to share the expertise and experiences of participants all over the world. This paper introduces a test part which has been designed to allow an analysis of different manufacturing technologies, simulation methods, machinery and metrology as well as process and production planning aspects. Current investigations are presented focusing on the machining and additive processes to produce the geometry, simulation approaches, machine analysis, and a comparison of measuring technologies. Challenges and limitations regarding the manufacturing and evaluation of the testpart features by the applied methods are discussed ispartof: pages:106-112 ispartof: Procedia CIRP vol:28 issue:28 pages:106-112 ispartof: 3rd CIRP Global Web Conference on Production Engineering Research - Advancement Beyond State of the Art (CIRPe) location:Naples, Italy date:3 Jun - 5 Jun 2014 status: published

The European project INCEFA-PLUS will characterize environmental fatigue in pressurized water reactor (PWR) conditions. The aim is to develop new guidelines for assessing environmental fatigue damage susceptibility of nuclear power plant (NPP) components. The consortium consists of 16 public and private organizations from across Europe. The project is structured in two phases: The first phase is an extensive fatigue testing program; in the second phase, a procedure for estimating the environmental fatigue degradation of the materials will be formulated. During the test phase, a selection of austenitic stainless steels used in NPPs will be characterized with regard to fatigue. The test matrix will focus on the effects of mean strain, strain amplitude, hold time periods, and surface roughness on fatigue life. Sensitivities to these parameters will be tested in PWR environments with additional tests in air for reference purposes. The study of hold time effects will lead to very long testing times, limiting the total number of tests. It is therefore crucial to establish a test matrix that allows the study of the principal effects of interest while taking into account the nuisance effects, such as different specimen geometries, particular material microstructures, and other laboratory-dependent factors that may not be well-controlled. Methods and considerations for establishing a single test matrix are presented in this work.

A distributed Web system, consisting of multiple servers for data retrieval and a Domain Name Server (DNS) for address resolution, can provide the scalability necessary to keep up with growing client demand at popular sites. However, balancing the requests among these atypical distributed servers opens interesting new challenges. Unlike traditional distributed systems in which a centralized scheduler has full control of the system, the DNS controls only a small fraction of the requests reaching the Web site. This makes it very difficult to avoid overloading situations among the multiple Web servers. We adapt traditional scheduling algorithms to the DNS, propose new policies, and examine their impact. Extensive simulation results show the advantage of using strategies that schedule requests on the basis of the origin of the clients and very limited state information, such as whether a server is overloaded or not. Conversely, algorithms that use detailed state information often exhibit the worst performance.