Search

This study introduces an innovative approach to optimize cloud computing job distribution using the Improved Dynamic Johnson Sequencing Algorithm (DJS). Emphasizing on-demand resource sharing, typical to Cloud Service Providers (CSPs), the research focuses on minimizing job completion delays through efficient task allocation. Utilizing Johnson's rule from operations research, the study addresses the challenge of resource availability post-task completion. It advocates for queuing models with multiple servers and finite capacity to improve job scheduling models, subsequently reducing wait times and queue lengths. The Dynamic Johnson Sequencing Algorithm and the M/M/c/K queuing model are applied to optimize task sequences, showcasing their efficacy through comparative analysis. The research evaluates the impact of makespan calculation on data file transfer times and assesses vital performance indicators, ultimately positioning the proposed technique as superior to existing approaches, offering a robust framework for enhanced task scheduling and resource allocation in cloud computing. [ABSTRACT FROM AUTHOR]

Blockchain is one of the leading technologies, and it has already begun to transform several industries and areas, including banking, business, healthcare, smart homes, and the Internet of Things. Its benefits include a decentralized network, robustness, availability, stability, anonymity, audibility, and accountability. As Blockchain applications proliferate, it becomes clear that most of the effort is focused on their engineering implementation. However, there has yet to be much focus on the theoretical side. This paper simulated the mining process in Blockchain-based systems using queuing theory. In order to simulate Bitcoin, one of the most well-known cryptocurrencies, we used actual data from Bitcoin and JSIMgraph's M/M/n/L queuing system. We used genuine Bitcoin data and JSIMgraph's M/M/n/L queuing system to replicate Bitcoin, one of the most well-known cryptocurrencies. We produced realistic results that are applicable and will pave the way for future theoretical research on Blockchain-based Queuing systems. Our study implemented both non-preemptive algorithms (such as First Come First Serve, Longest Job First, Shortest Job First, and Last Come First Serve) and preemptive algorithms (such as Round Robin). Further, the average queue waiting time of transactions under these algorithms is also compared. [ABSTRACT FROM AUTHOR]

Image analysis techniques have been applied and shown to be a valuable tool in nuclear forensics analysis. The interlaboratory exercise reported here has tested quantitative and qualitative approaches for characterizing nuclear materials. Particle size, surface features and morphology descriptions were compared by four laboratories on a common image set generated by Scanning Electron Microscopy and Digital Light Microscopy. Quantitative analysis of the image sets through the Morphological Analysis for MAterials software highlighted the strength of image analysis, but also that the application of the software alone can introduce significant bias in the analysis. Qualitative morphology descriptions following the process outlined by Tamasi et al. (J Radioanal Nuclear Chem 307:1611–1619, 2015) were compared with a discussion on the robustness and reproducibility of the results. Future work should continue to focus on proficiency and standardization of image analysis through continued exercises within the extended nuclear forensics community. [ABSTRACT FROM AUTHOR]

Salt crystallization is a major cause of damage in porous building materials. Accelerated salt weathering tests carried out in the laboratory are among the most common methods to assess the durability of material to salt decay. However, existing standards and recommendations for salt weathering tests have limitations in terms of effectiveness and/or reliability. In the framework of the RILEM Technical Committee 271-ASC, a procedure has been developed which proposes a new approach to salt crystallization tests. It starts from the consideration that salt damage can be seen as a process developing in two phases: accumulation of the salt in the material and propagation of the decay. In the first phase, salts are introduced in the material and accumulate close to the evaporation surface, while in the second phase damage propagates because of repeated dissolution and crystallization cycles, induced by re-wetting with liquid water and by relative humidity changes. In this paper, the procedure is described and the results of a first round robin validation of the test, carried out on 7 materials and involving 10 laboratories, are presented. The results show that the procedure is effective to cause decay within the time period of the test (about 3 months) and that the decay increases with subsequent cycles. The decay observed differs in type and severity depending on the salt type and concentration and on the type of substrate. The decay types detected in the laboratories are generally representative of those observed in the field for the selected substrates. The differences in durability between the various substrates, as assessed at the end of the test, are in line with the durability expected based on field observation. The reproducibility of the results in terms of decay type is good; some differences have been observed in terms of material loss. These are more significant in the case of NaCl contaminated specimens. Based on the results, proposals for fine-tuning of the procedure are given. [ABSTRACT FROM AUTHOR]

Cloud computing is a platform that provides many applications based on cloud infrastructure. It provides the facility of using different resources such as data storage, databases, networking, etc. The main problem in the cloud computing environment is task scheduling which plays an important role in optimizing the total execution time. In this paper, a comparison of scheduling algorithms such as First Come First Serve, Round Robin, min–min and max–min is done based on makespan using workflows as datasets. Comparison is done in by increasing the number of virtual machines Workflowsim environment. Experimental results show a decrease in makespan as the number of Virtual Machines is increased. For CyberShake workflow First Come First Serve algorithm has performed 3.69% better than Round Robin, outperformed 13.38% than min–min, and has given 22.68% better results than max–min. In the case of Montage workflow, max–min has performed 26.73% better than First Come First Serve, 17.73% than Round Robin, and has given 4.63% better results than min–min. [ABSTRACT FROM AUTHOR]

With the increasing growth in the network and latest technologies by which people communicates via voice or data and modifies the radio devices easily and cost effectively. Software defined radio brings the flexibility, power and efficiency including cloud and big data, control and management of the traditional networks has raised the challenges for the development of multimedia applications. Multimedia applications require to handle the large amount of data at the servers which has increased the load on them. To resolve this issue, Software Defined Networking (SDN) came into existence which makes the management of the network more conformable. To satisfy the constraints of Quality of Service (QoS) and Quality of Experience (QoE) with the limited network availability, one of the keynotes that have been taken into consideration is the load balancing. Therefore, many servers can be used with the load balancers which behave as the front end. The present paper aims to reflect impact on the efficiency of the usage of software-defined networks service in various multimedia applications. A genetic load balancing algorithm (GLBA) is proposed and is implemented on POX controller with mininet emulator in python language to compute its effectiveness and efficiency. Validation of GLBA for 100 to 600 users over server load, weighted round robin, round robin, dynamic server and LBBSRT algorithms with parameters, throughput, response time, memory and CPU utilization has proved the significance of proposed algorithm. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The purpose of LTE-A technology is to provide high spectral efficiency, lower delay and stronger intercell interference control for a multi- user environment. The architecture of LTE basically contains E-UTRAN and evolved packet core. E-UTRAN is the combination of UE and ENodeB (enhanced node B) used to control the radio network. EPC provide end to end connection and backward capability with previous networks. Major entities included in EPC are P-GW, S-GW, HSS and MME. This new architecture fulfil the requirement of next-generation mobile networks for high connectivity and multiple type of networks. Heterogeneous network is one of them in which different power base stations like femtocell, picocell, and radio remote head deployed in a geographical area with in macrocell cell. It is one of the cost effective solution to provide high throughput and spectral efficiency and fairness for cell edge user. Deployment of femtocell improved the data rate and coverage in small regions like office, home, shopping mall and dense areas. Along with this an efficient fair sharing of resource allocation plays an important role in improving the performance of networks. This paper analysed the performance of round robin, resource fair, Max-throughput, best CQI and proportional fair LTE-A resource scheduling techniques on homogeneous networks. For heterogeneous networks a new cluster based proportional fair resource scheduling technique is proposed, which provides an efficient resource to the most sufferer user and improved fairness and cell edge user throughputs. In heterogeneous networks multiple femto cell were deployed in macro cell area. Access policies are applied on open and closed group. The performance is measured in terms of cell edge throughputs, peak throughputs, average throughputs, wideband SINR, spectral efficiency, and fairness index for homogeneous, heterogeneous networks and for user mobility. The performance result showed that Best CQI and MaxTP scheduler outperforms in throughput level and attains highest average cell throughput of 83 Mbps and UE average throughput of 20 mbps in homogeneous networks and approximately 43 Mbps in heterogeneous networks. Comparative result in heterogeneous network indicates that the proposed scheduler increases 2% gain in fairness and 1–1.89% gains in edge throughputs with respect to proportional fair scheduler and allocates 79% fair share resources among UE. Round robin scheduler delivered very poor throughput and fairness index in both homogeneous and heterogeneousnetworks. [ABSTRACT FROM AUTHOR]

Many standardised durability testing methods have been developed for Portland cement-based concretes, but require validation to determine whether they are also applicable to alkali-activated materials. To address this question, RILEM TC 247-DTA ‘Durability Testing of Alkali-Activated Materials’ carried out round robin testing of carbonation and chloride penetration test methods, applied to five different alkali-activated concretes based on fly ash, blast furnace slag or metakaolin. The methods appeared overall to demonstrate an intrinsic precision comparable to their precision when applied to conventional concretes. The ranking of test outcomes for pairs of concretes of similar binder chemistry was satisfactory, but rankings were not always reliable when comparing alkali-activated concretes based on different precursors. Accelerated carbonation testing gave similar results for fly ash-based and blast furnace slag-based alkali-activated concretes, whereas natural carbonation testing did not. Carbonation of concrete specimens was observed to have occurred already during curing, which has implications for extrapolation of carbonation testing results to longer service life periods. Accelerated chloride penetration testing according to NT BUILD 443 ranked the tested concretes consistently, while this was not the case for the rapid chloride migration test. Both of these chloride penetration testing methods exhibited comparatively low precision when applied to blast furnace slag-based concretes which are more resistant to chloride ingress than the other materials tested. [ABSTRACT FROM AUTHOR]

We investigated the ability of undergraduate students to detect psychopathic personality traits in their new peers, after engaging in limited, naturalistic contact. Research has demonstrated that personality traits can be socially recognised in others. However, this research has not yet explored the recognition of psychopathic personality traits in newly encountered peers. This is important as some of these traits, such as manipulation, can have important social consequences in forming friendships. At the same time, manipulative tendencies only work best when not seen as such. To study the salience of psychopathic personality traits, undergraduate students (N = 101) took part in a round robin judgment paradigm during their orientation period of university. We found that participants were able to detect the Triarchic Psychopathy Measure's traits of Boldness and Disinhibition but not Meanness in their groups, using typical social judgments. However, Meanness was the only trait that notably related to judges reporting that they would not make friends with targets who showed more psychopathic personality traits. These results highlight the importance of psychopathic personality traits when students form first impressions and intentions to make friends. Future research should consider the influence of 'hidden' meanness even in sub-clinical populations. [ABSTRACT FROM AUTHOR]

Technology behind every communication systems, especially commercial applications requires periodic modifications to satisfy the subscriber's desires. A bulk of handheld radio access devices are emerging in the market every day. Since radio resources are limited and expensive, Device to device communication underlying New Radio (NR-gNodeB) access network is encouraged in fifth generation (5G) systems. But such system may be a catalyst for interference. At present, the research hotspot is to find ideal solution for resource allocation and interference management. This paper emphasis the requirements of 5G system and its physical layer design. Further the intention is to mitigate interference in such system so that functionalities of scheduling schemes such as Greedy, Round Robin and Proportional fair algorithms are analyzed for efficient resource allocation. The simulation results explore that, the coded generalized frequency division multiplexing (GFDM) system results in higher transmission rate. Also, coded GFDM with proportional fair scheduler results in high throughput and reduced latency with no compromise in its fairness. In summary, the proposed scheme could be a wise choice for reliable communication in smart cities. [ABSTRACT FROM AUTHOR]

In this paper, we evaluate the theoretical bit error probability (BEP) of round robin, centralized and distributed relay selection for cooperative systems. Centralized relay selection activates the relay with the largest end-to-end signal-to-noise ratio (SNR) using a central node that will collect and compare these SNRs. In distributed relay selection, each relay compares its SNR to a predefined threshold T and is activated only when its SNR is larger than T. The threshold T is numerically optimized to have the lowest BEP. The network contains three nodes: one node acting as a source and the other two as destination. One of the destinations is selected to relay the signal to other destination node. Round robin relay selection consists to alternatively assign a node as relay. We also study relay selection for cognitive radio networks. The relay node should generate interference to primary receiver lower than a predefined threshold β. [ABSTRACT FROM AUTHOR]

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 Q or Q are done mutually two tasks from Q and one task from Q. 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. [ABSTRACT FROM AUTHOR]

Cognitive radio (CR) is a popular wireless technology for efficient utilization of spectrum. CR network senses the unused frequency bands of the primary users (PUs) and assign them to the unlicensed secondary users (SUs). One of the major challenges in cognitive network is the allocation of available spectrum which indirectly contributes to the efficient spectrum utilization. A novel intelligent dynamic spectrum allocation with bandwidth flexibility is presented in this paper. Fuzzy inference system has been used to evaluate and rate the channel (CH) quality and the SU. The quality based spectrum allocation has been carried out. As the primary CH bandwidth differ from the SU and in the case, the SU bandwidth is lower to PU, accommodation of more than one secondary CH into primary is possible. To utilize this facility, bandwidth flexibility is incorporated in the intelligent spectrum allocation. The intelligent spectrum allocation techniques are compared with the sequence based method of spectrum allocation and priority based allocation. The quality measures utilized for comparison are service rate, average packet loss and average delay. On these measures intelligent dynamic bandwidth flexible spectrum allocation method is found to be better, compared to other three methods. [ABSTRACT FROM AUTHOR]

Six different organizations participated in this interlaboratory study to quantify the variability in the tensile properties of Inconel 625 specimens manufactured using laser powder bed fusion-additive manufacturing machines. The tensile specimens were heat treated and tensile tests were conducted until failure. The properties measured were yield strength, ultimate tensile strength, elastic modulus, and elongation. Statistical analysis revealed that between-participant variability for yield strength, ultimate tensile strength, and elastic modulus values were significantly higher (up to four times) than typical within-participant variations. Only between-participant and within-participant variability were both similar for elongation. A scanning electron microscope was used to examine one tensile specimen for fractography. The fracture surface does not have many secondary cracks or other features that would reduce the mechanical properties. In fact, the features largely consist of microvoid coalescence and are entirely consistent with ductile failure. [ABSTRACT FROM AUTHOR]

A round robin on GPC of a wide range of different pulp samples was conducted among leading groups in cellulose analysis. The aim was to survey the status quo of the methods available to date. The pulp samples covered not only fully-bleached dissolving pulps but also bleached paper pulps and one unbleached sample. The methods applied were current state-of-the-art GPC with RI, MALLS, and viscosimetry detectors. Different dissolution protocols were compared as well. Following from the obtained results, more standardized protocols were proposed for approaches with different equipment (RI or MALLS/RI) and solvent systems (direct dissolution or derivatization). Major influencing factors, such as derivatization compared to direct solution, calibration versus light scattering and in-between lab variation, were discussed. [ABSTRACT FROM AUTHOR]

Hierarchical Modulation (HM) is a means to enhance the spectral efficiency of a system by superposing, in terms of modulation, an additional stream for a given user with good radio conditions on a basic stream of a user with worse radio conditions. This, in turn, increases the throughput of the former user and hence the overall performance of the whole system. We consider, in this work, such a performance at the flow level, for a realistic dynamic setting where users come to the system and leave it after a finite duration corresponding, for instance, to the completion of a file transfer. We specifically model and quantify, both analytically and via simulations, the gain thus achieved and propose two extensions to the basic HM algorithm: a first one in which a user with bad radio conditions is also superposed on one with better radio conditions and a second one in which a user of one type is further superposed on a user of the same type as well. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The carry-over effects value is one of the various measures one can consider to assess the quality of a round robin tournament schedule. We introduce and discuss a new, weighted variant of the minimum carry-over effects value problem. The problem is formulated by integer programming and an algorithm based on the hybridization of the Iterated Local Search metaheuristic with a multistart strategy is proposed. Numerical results are presented. [ABSTRACT FROM AUTHOR]

Seven algae samples, five purchased from food stores and two reference algae (BCR 279 Sea Lettuce) were distributed as blind samples to 13 laboratories from which five labs attempted a full characterisation of the water-soluble fraction with respect to their arsenic species. The extraction efficiency is largely dependant on the algae and varied from 3% to 96%. Besides inorganic arsenic (mainly as As(V)) DMA(V) and, in particular, several arsenosugars were identified in all samples. From the five labs, three labs gave agreeable results in respect of the arsenic species identification and its quantification, although different chromatographic methods were used. Different Hijiki samples seem to contain largely different arsenic concentration (67–113 mg As/kg) which may also have an influence on the distribution of inorganic arsenic and arsenosugars. [ABSTRACT FROM AUTHOR]

A new approximation of fair queuing called Compensating Round Robin (CRR) is presented in this paper. The algorithm uses packet-by-packet scheduler with a compensating measure. It achieves good fairness in terms of throughput, requires only O(1) time complexity to process a packet, and is simple enough to be implemented in hardware. After the performances are analyzed, the fairness and packet loss rate of the algorithm are simulated. Simulation results show that the CRR can effectively isolate the effects of contending sources. [ABSTRACT FROM AUTHOR]

Fairness, latency and computational complexity are three important factors in evaluating the performance of a scheduling algorithm. Fairness must be satisfied so that service can be distributed according to the reserved rate. Only when latency is irrelevant to the number of connections, is it possible to minimize the end-to-end delay through controlling the reserved rate. Among existing scheduling algorithms, Round Robin is the least complex. However, conventional Round Robin is unable to ensure fairness, and the improved round robin algorithms like Deficit Round Robin, Weighted Round Robin and Virtual Round Robin are unable to ensure that their latencies are irrelevant to the number of connections although they guarantee fairness. Potential Round Robin developed for analysis of fairness and latency reduction is thus proposed. It is based on the introduction of a new concept, Round Potential Function. The function splits service time into a number of service round periods to guarantee fairness regardless of the serving process used in the period. In the analysis of latency, service round periods are re-split into multiple scanning cycles for further service distribution with approximate sorting between scanning cycles. As a result, latency is no longer relevant to the number of connections while the low complexity of round robin is kept. [ABSTRACT FROM AUTHOR]

The RILEM technical committee TC 247-DTA 'Durability Testing of Alkali-Activated Materials' conducted a round robin testing programme to determine the validity of various durability testing methods, originally developed for Portland cement based-concretes, for the assessment of the durability of alkali-activated concretes. The outcomes of the round robin tests evaluating sulfate resistance, alkali-silica reaction (ASR) and freeze–thaw resistance are presented in this contribution. Five different alkali-activated concretes, based on ground granulated blast furnace slag, fly ash, or metakaolin were investigated. The extent of sulfate damage to concretes based on slag or fly ash seems to be limited when exposed to an Na2SO4 solution. The mixture based on metakaolin showed an excessive, very early expansion, followed by a dimensionally stable period, which cannot be explained at present. In the slag-based concretes, MgSO4 caused more expansion and visual damage than Na2SO4; however, the expansion limits defined in the respective standards were not exceeded. Both the ASTM C1293 and RILEM AAR-3.1 test methods for the determination of ASR expansion appear to give essentially reliable identification of expansion caused by highly reactive aggregates. Alkali-activated materials in combination with an unreactive or potentially expansive aggregate were in no case seen to cause larger expansions; only the aggregates of known very high reactivity were seen to be problematic. The results of freeze–thaw testing (with/without deicing salts) of alkali-activated concretes suggest an important influence of the curing conditions and experimental conditions on the test outcomes, which need to be understood before the tests can be reliably applied and interpreted. [ABSTRACT FROM AUTHOR]

The aim of RILEM TC 247-DTA 'Durability Testing of Alkali-Activated Materials' is to identify and validate methodologies for testing the durability of alkali-activated concretes. To underpin the durability testing work of this committee, five alkali-activated concrete mixes were developed based on blast furnace slag, fly ash, and flash-calcined metakaolin. The concretes were designed with different intended performance levels, aiming to assess the capability of test methods to discriminate between concretes on this basis. A total of fifteen laboratories worldwide participated in this round robin test programme, where all concretes were produced with the same mix designs, from single-source aluminosilicate precursors and locally available aggregates. This paper reports the mix designs tested, and the compressive strength results obtained, including critical insight into reasons for the observed variability in strength within and between laboratories. [ABSTRACT FROM AUTHOR]