3,994 results on '"mpi"'
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2. To Share or Not to Share: A Case for MPI in Shared-Memory
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Adam, Julien, Besnard, Jean-Baptiste, Roussel, Adrien, Jaeger, Julien, Carribault, Patrick, Pérache, Marc, Goos, Gerhard, Series Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Blaas-Schenner, Claudia, editor, Niethammer, Christoph, editor, and Haas, Tobias, editor
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- 2025
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3. Stream Support in MPI Without the Churn
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Schuchart, Joseph, Gabriel, Edgar, Goos, Gerhard, Series Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Blaas-Schenner, Claudia, editor, Niethammer, Christoph, editor, and Haas, Tobias, editor
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- 2025
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4. MPI-BugBench: A Framework for Assessing MPI Correctness Tools
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Jammer, Tim, Saillard, Emmanuelle, Schwitanski, Simon, Jenke, Joachim, Vinayagame, Radjasouria, Hück, Alexander, Bischof, Christian, Goos, Gerhard, Series Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Blaas-Schenner, Claudia, editor, Niethammer, Christoph, editor, and Haas, Tobias, editor
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- 2025
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5. Understanding GPU Triggering APIs for MPI+X Communication
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Bridges, Patrick G., Skjellum, Anthony, Suggs, Evan D., Schafer, Derek, Bangalore, Purushotham V., Goos, Gerhard, Series Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Blaas-Schenner, Claudia, editor, Niethammer, Christoph, editor, and Haas, Tobias, editor
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- 2025
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6. Annotation of Compiler Attributes for MPI Functions
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Jammer, Tim, Schmidt, Adrian, Bischof, Christian, Goos, Gerhard, Series Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Blaas-Schenner, Claudia, editor, Niethammer, Christoph, editor, and Haas, Tobias, editor
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- 2025
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7. Proteo: a framework for the generation and evaluation of malleable MPI applications.
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Martín-Álvarez, Iker, Aliaga, José I., Castillo, Maribel, and Iserte, Sergio
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POSSIBILITY - Abstract
Applying malleability to HPC systems can increase their productivity without degrading or even improving the performance of running applications. This paper presents Proteo, a configurable framework that allows to design benchmarks to study the effect of malleability on a system, and also incorporates malleability into a real application. Proteo consists of two modules: SAM allows to emulate the computational behavior of iterative scientific MPI applications, and MaM is able to reconfigure a job during execution, adjusting the number of processes, redistributing data, and resuming execution. An in-depth study of all the possibilities shows that Proteo is able to behave like a real malleable or non-malleable application in the range [0.85, 1.15]. Furthermore, the different methods defined in MaM for process management and data redistribution are analyzed, concluding that asynchronous malleability, where reconfiguration and application execution overlap, results in a 1.15 × speedup. [ABSTRACT FROM AUTHOR]
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- 2024
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8. EFFECTIVENESS OF MANNHEIM PERITONITIS INDEX IN PREDICTING MORTALITY IN PATIENTS WITH PERFORATION PERITONITIS.
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Dudeja, Devyani, Das, Nabajyoti, and Bhuyan, S.
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ABDOMEN , *PERITONITIS , *SURGICAL emergencies , *HOSPITAL emergency services , *SEPSIS - Abstract
Background: Peritonitis is defined as inflammation of the serous membrane that lines the abdominal cavity and the organs contained therein. It is still one of the most important and common infectious problems that a surgeon must face. In this study we have taken into account all the parameters of Mannheim’s peritonitis index for predicting mortality and we have found the positive correlation among them. Aims And Objectives: To evaluate the outcome of patients using MPI and to confirm its predictive value. Materials And Method: It is a prospective study done in department of surgery for an approximate period of two years including patients attending surgery emergency department with features of peritonitis and excluding patients with primary and tertiary peritonitis. The sampling method used is nonrandomised sampling. Results And Observations: In our study we found max. patients in age of 25-35 i.e, 56(37%). Male sex (65%) has predominance. Most common site of perforation was found to be duodenal 53 (35%) and the most common clinical feature was pain in abdomen in 97% and not passing flatus and feces in 80%. Evidence of organ failure was seen in approx. 20% (30) of patients. Presentation of patients within 24 hrs was just 12% (18). Presence of malignancy was found in 12(8%) patients. 79% (118) patients had generalised peritonitis with 56% (84) having purulent exudate. Origin of sepsis was noncolonic in 128(85%) patients. maximum patients had MPI score of <21 i.e, 55% (83). 15(10%) patients expired with maximum patients had MPI of >29. Conclusions: Mannheim Peritonitis index is a useful method to determine study group outcome in patients with peritonitis. All the MPI variables of adverse outcome namely, presence of organ failure; time elapsed > 24hrs; presence of malignancy; age>50 years, generalized extension of peritonitis and type of exudate behaved as expected, except the noncolonic origin of sepsis in peritonitis and female sex. As our study differs in two adverse outcome variables, female sex & noncolonic origin of sepsis, we advocate need for further studies on Mannheim Peritonitis index to include colonic origin of sepsis and to remove female sex as variables of adverse outcome in Mannheim Peritonitis index. [ABSTRACT FROM AUTHOR]
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- 2024
9. Network states-aware collective communication optimization.
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Wang, Jingyuan, Zhao, Tianhai, and Wang, Yunlan
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MESSAGE passing (Computer science) , *TELECOMMUNICATION systems , *ALGORITHMS , *HETEROGENEITY , *DEFAULT (Finance) - Abstract
Message Passing Interface (MPI) is the de facto standard for parallel programming, and collective operations in MPI are widely utilized by numerous scientific applications. The efficiency of these collective operations greatly impacts the performance of parallel applications. With the increasing scale and heterogeneity of HPC systems, the network environment has become more complex. The network states vary widely and dynamically between node pairs, and this makes it more difficult to design efficient collective communication algorithms. In this paper, we propose a method to optimize collective operations by using real-time measured network states, specifically focusing on the binomial tree algorithm. Our approach employs a low-overhead method to measure the network states, and the binomial tree with small latency is constructed based on the measurement result. Additionally, we take into account the disparities between the two underlying MPI peer-to-peer communication protocols, eager and rendezvous, and design tailored binomial tree construction algorithms for each protocol. We have implemented hierarchical MPI_Bcast, MPI_Reduce, MPI_Gather and MPI_Scatter, utilizing our network states-aware binomial tree algorithm at the inter-node level. The benchmark results demonstrate that our algorithm effectively enhances performance in small and medium message communication when compared to the default binomial tree algorithm in Open MPI. Specifically, for MPI_Bcast, we observe an average performance improvement of over 15.5% when the message size is less than 64KB. Similarly, for MPI_Reduce, there is an average performance improvement of over 12.1% when the message is below 2KB. In addition, there is an average performance improvement of over 10% for MPI_Gather when the message ranging from 64B to 512B. For MPI_Scatter, our algorithm achieved performance improvement only for certain message sizes. [ABSTRACT FROM AUTHOR]
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- 2024
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10. Is It Diabetes or Just Macrosomia? Fetal Myocardial Performance Index in Large-for-Gestational Age Fetuses.
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Ayhan, Işıl and Uygur, Lütfiye
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FETAL macrosomia , *CEREBRAL arteries , *POLYHYDRAMNIOS , *DIABETES , *FETUS - Abstract
Our aim in this study was to investigate whether there is an association between large-for-gestational age (LGA) fetuses and myocardial performance index (MPI). This is a cross-sectional study conducted from July 2022 to July 2023. Prospectively gathered data from 65 LGA cases and 65 age and gestational-age (GA)-matched controls were analyzed. Presence of polyhydramnios and diabetes were recorded in the study group. Fetal left ventricular mod-MPI, peak systolic velocity (PSV) of E and A waves, umbilical and middle cerebral artery (MCA) pulsatility indexes (PI) were sonographically measured. Association between these sonographic measures and LGA fetuses were sought. The LGA group had 33 diabetic cases (22 GDM and 11 PGDM). The LGA group had greater mod-MPI (0.51 vs. 0.45, p = 0.0048). The LGA group also had prolonged isovolumetric contraction time (ICT), compared to controls (37 ms vs. 33 ms, p = 0.008). ICT was longer in LGA fetuses with non-diabetic mothers (38 ms vs. 33 ms, p = 0.009). LGA fetuses with polyhydramnios but without diabetic mothers had also longer ICT (39 ms vs. 33 ms, p = 0.002). Mod-MPI was similar in controls and LGA without diabetes/LGA with polyhydramnios but without diabetes subgroups. Our results indicate that fetal mod-MPI values are higher in LGA fetuses and ICT is prolonged among LGA fetuses irrespective of presence of maternal diabetes. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Risk Management of Physical Assets Supported by Maintenance Performance Indicators.
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da Silva, Renan Favarão, Melani, Arthur Henrique de Andrade, Michalski, Miguel Angelo de Carvalho, Souza, Gilberto Francisco Martha de, and Nabeta, Silvio Ikuyo
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Many asset-intensive organizations implement risk management strategies to mitigate potential hazards associated with physical asset failures, such as infrastructure deterioration or mechanical breakdown. As these physical assets' risks can be treated with maintenance activities, properly evaluating the performance of maintenance management is of interest for risk management. Accordingly, this paper proposes a framework for the determination of Maintenance Performance Indicators (MPIs) to support the risk management of physical assets. The proposed framework included four main processes: Integrate performance evaluation guidelines, Review the maintenance management strategy, Define the performance indicators, and Assess maintenance across the MPIs. The ISO 55000 series for asset management and the Balanced Scorecard (BSC) approach were the guidelines considered. The ISO 55001 standard provides three assessment domains for performance evaluation: asset portfolio, asset management, and asset management system. The BSC approach identifies four performance evaluation perspectives that were integrated to address the requirements of one of these asset management domains. Then, the MPIs were defined for each of the performance evaluation domains in line with the maintenance management strategy toward the risk management of physical assets. Through a case study, the proposed framework was demonstrated considering the operational context of a Brazilian hydroelectric power plant. As a result, the proposed framework was shown to be consistent in systematically determining the MPIs that support risk management in organizations. [ABSTRACT FROM AUTHOR]
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- 2024
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12. Analysis and prediction of performance variability in large-scale computing systems.
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Salimi Beni, Majid, Hunold, Sascha, and Cosenza, Biagio
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COMPUTER systems , *SUPERCOMPUTERS , *COMMUNICATION patterns , *JOB performance , *RESOURCE management , *TOPOLOGY - Abstract
The development of new exascale supercomputers has dramatically increased the need for fast, high-performance networking technology. Efficient network topologies, such as Dragonfly+, have been introduced to meet the demands of data-intensive applications and to match the massive computing power of GPUs and accelerators. However, these supercomputers still face performance variability mainly caused by the network that affects system and application performance. This study comprehensively analyzes performance variability on a large-scale HPC system with Dragonfly+ network topology, focusing on factors such as communication patterns, message size, job placement locality, MPI collective algorithms, and overall system workload. The study also proposes an easy-to-measure metric for estimating network background traffic generated by other users, which can be used to estimate the performance of our job accurately. The insights gained from this study contribute to improving performance predictability, enhancing job placement policies and MPI algorithm selection, and optimizing resource management strategies in supercomputers. [ABSTRACT FROM AUTHOR]
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- 2024
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13. PARamrfinder: detecting allele-specific DNA methylation on multicore clusters.
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Fernández-Fraga, Alejandro, González-Domínguez, Jorge, and Martín, María J.
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DNA methylation , *SINGLE nucleotide polymorphisms , *GENOMIC imprinting , *DYNAMIC balance (Mechanics) , *MULTICORE processors , *SOURCE code , *PARALLEL programming - Abstract
The discovery of Allele-Specific Methylation (ASM) is an important research field in biology as it regulates genomic imprinting, which has been identified as the cause of some genetic diseases. Nevertheless, the high computational cost of the bioinformatic tools developed for this purpose prevents their application to large-scale datasets. Hence, much faster tools are required to further progress in this research field. In this work we present PARamrfinder, a parallel tool that applies a statistical model to identify ASM in data from high-throughput short-read bisulfite sequencing. It is based on the state-of-the-art sequential tool amrfinder, which is able to detect ASM at regional level from Bisulfite Sequencing (BS-Seq) experiments in the absence of Single Nucleotide Polymorphism information. PARamrfinder provides the same Allelically Methylated Regions as amrfinder but at significantly reduced runtime thanks to exploiting the compute capabilities of common multicore CPU clusters and MPI RMA operations to attain an efficient dynamic workload balance. As an example, our tool is up to 567 times faster for real data experiments on a cluster with 8 nodes, each one containing two 16-core processors. The source code of PARamrfinder, as well as a reference manual, is available at https://github.com/UDC-GAC/PARamrfinder. [ABSTRACT FROM AUTHOR]
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- 2024
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14. MPI-Based Methods for Network Reliability Calculation.
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Migov, D. A.
- Abstract
The paper considers the problem of exact network reliability calculation. We assume that a network has unreliable communication links and perfectly reliable nodes. The reliability for such network is defined as a probability that every pair of nodes of network is connected by an operational path. The problem of computing this characteristic is known to be NP-hard. For supercomputers with distributed memory, we study the ways of parallelization of the well-know recursive factoring method. The best parallel algorithm among approaches considered is the algorithm based on a Master-Slave scheme using a threshold for the minimal size of a graph for sending it to a new process without recursion backtracking. This algorithm has a linear or even superlinear speedup up to 768 cores. The numerical results show that the scalability depends on the chosen threshold for the minimal size of a graph for sending to a new process, which, in turn, depends on the density of the graph. [ABSTRACT FROM AUTHOR]
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- 2024
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15. MPI/OpenMP-Based Parallel Solver for Imprint Forming Simulation.
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Yang Li, Jiangping Xu, Yun Liu, Wen Zhong, and Fei Wang
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COMMEMORATIVE coins ,MESSAGE passing (Computer science) ,COINS ,COMPUTER simulation ,TETRAHEDRA ,PARALLEL algorithms - Abstract
In this research, we present the pure open multi-processing (OpenMP), pure message passing interface (MPI), and hybrid MPI/OpenMP parallel solvers within the dynamic explicit central difference algorithm for the coining process to address the challenge of capturing fine relief features of approximately 50 microns. Achieving such precision demands the utilization of at least 7 million tetrahedron elements, surpassing the capabilities of traditional serial programs previously developed. To mitigate data races when calculating internal forces, intermediate arrays are introduced within the OpenMP directive. This helps ensure proper synchronization and avoid conflicts during parallel execution. Additionally, in the MPI implementation, the coins are partitioned into the desired number of regions. This division allows for efficient distribution of computational tasks across multiple processes. Numerical simulation examples are conducted to compare the three solvers with serial programs, evaluating correctness, acceleration ratio, and parallel efficiency. The results reveal a relative error of approximately 0.3% in forming force among the parallel and serial solvers, while the predicted insufficient material zones align with experimental observations. Additionally, speedup ratio and parallel efficiency are assessed for the coining process simulation. The pureMPI parallel solver achieves a maximum acceleration of 9.5 on a single computer (utilizing 12 cores) and the hybrid solver exhibits a speedup ratio of 136 in a cluster (using 6 compute nodes and 12 cores per compute node), showing the strong scalability of the hybrid MPI/OpenMP programming model. This approach effectively meets the simulation requirements for commemorative coins with intricate relief patterns. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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16. MPI System with Bore Sizes of 75 mm and 100 mm Using Permanent Magnets and FMMD Technique.
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Jeong, Jae Chan, Kim, Tae Yi, Cho, Hyeon Sung, Seo, Beom Su, Krause, Hans Joachim, and Hong, Hyo Bong
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MAGNETIC particle imaging , *MECHANICAL movements , *IMAGE reconstruction , *SUPERCONDUCTING coils , *FERRIC oxide , *ENERGY consumption - Abstract
We present two magnetic particle imaging (MPI) systems with bore sizes of 75 mm and 100 mm, respectively, using three-dimensionally arranged permanent magnets for excitation and frequency mixing magnetic detection (FMMD) coils for detection. A rotational and a translational stage were combined to move the field free line (FFL) and acquire the MPI signal, thereby enabling simultaneous overall translation and rotational movement. With this concept, the complex coil system used in many MPI systems, with its high energy consumption to generate the drive field, can be replaced. The characteristic signal of superparamagnetic iron oxide (SPIO) nanoparticles was generated via movement of the FFL and acquired using the FMMD coil. The positions of the stages and the occurrence of the f1 + 2f2 harmonics were mapped to reconstruct the spatial location of the SPIO. Image reconstruction was performed using Radon and inverse Radon transformations. As a result, the presented method based on mechanical movement of permanent magnets can be used to measure the MPI, even for samples as large as 100 mm. Our research could pave the way for further technological developments to make the equipment human size, which is one of the ultimate goals of MPI. [ABSTRACT FROM AUTHOR]
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- 2024
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17. Prognostic Features of Sarcopenia in Older Hospitalized Patients: A 6-Month Follow-Up Study.
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Ferring, Anne, Mück, Luisa, Stegemann, Jill, Wiebe, Laura, Becker, Ingrid, Benzing, Thomas, Meyer, Anna Maria, and Polidori, Maria Cristina
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SARCOPENIA , *GERIATRIC Depression Scale , *OLDER people , *BIOELECTRIC impedance , *GERIATRIC assessment - Abstract
Background: Sarcopenia is associated with adverse health outcomes. Understanding the association between sarcopenia, multidimensional frailty, and prognosis is essential for improving patient care. The aim of this study was to assess the prevalence and prognostic signature of sarcopenia in an acute hospital setting co-led by internists and geriatricians. Methods: Sarcopenia was assessed by applying the European Working Group on Sarcopenia in Older People (EWGSOP2) algorithm, including the SARC-F score, handgrip strength, bioelectrical impedance analysis (BIA), and Timed Up and Go (TUG) test, to 97 older multimorbid inpatients (76.5 ± 6.8 years, 55% women). The patients underwent a Comprehensive Geriatric Assessment (CGA) including an evaluation of Geriatric Syndromes (GSs) and Resources (GR) and prognosis calculation using the CGA-based Multidimensional Prognostic Index (MPI), European Quality of life—5 Dimensions (EQ-5D-5L) scale, Rosenberg Self-Esteem Scale (RSES), and Geriatric Depression Scale (GDS). Information on survival and rehospitalizations was collected 1, 3, and 6 months after discharge. Results: Sarcopenia was present in 63% (95% CI: 54–72%) of patients and categorized as probable (31%), confirmed (13%), and severe sarcopenia (18%). Sarcopenic patients showed significantly higher median MPI-values (p < 0.001), more GSs (p = 0.033), fewer GR (p = 0.003), lower EQ-5D-5L scores (p < 0.001), and lower RSES scores (p = 0.025) than non-sarcopenic patients. Six months after discharge, being sarcopenic at baseline was predictive of falls (p = 0.027) and quality of life (p = 0.043), independent of age, gender, and MPI. Conclusions: Sarcopenia is highly prevalent in older hospitalized multimorbid patients and is associated with poorer prognosis, mood, and quality of life up to 6 months after discharge, independent of age, sex, and MPI as surrogate markers of biological age. [ABSTRACT FROM AUTHOR]
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- 2024
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18. Automatic Discovery of Collective Communication Patterns in Parallelized Task Graphs.
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Knorr, Fabian, Salzmann, Philip, Thoman, Peter, and Fahringer, Thomas
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COMMUNICATION patterns , *DEGREES of freedom , *HIGH performance computing - Abstract
Collective communication APIs equip MPI vendors with the necessary context to optimize cluster-wide operations on the basis of theoretical complexity models and characteristics of the involved interconnects. Modern HPC runtime systems with a programmability focus can perform dependency analysis to eliminate the need for manual communication entirely. Profiting from optimized collective routines in this context often requires global analysis of the implicit point-to-point communication pattern or tight constrains on the data access patterns allowed inside kernels. The Celerity API provides a high degree of freedom for both runtime implementors and application developers by tieing transparent work assignment to data access patterns through user-defined range-mapper functions. Canonically, data dependencies are resolved through an intra-node coherence model and inter-node point-to-point communication. This paper presents Collective Pattern Discovery (CPD), a fully distributed, coordination-free method for detecting collective communication patterns on parallelized task graphs. Through extensive scheduling and communication microbenchmarks as well as a strong scaling experiment on a compute-intensive application, we demonstrate that CPD can achieve substantial performance gains in the Celerity model. [ABSTRACT FROM AUTHOR]
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- 2024
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19. Performance Evaluation of Recursive Mean Filter Using Scilab, MATLAB, and MPI (Message Passing Interface) †.
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Andreeva, Hristina and Bosakova-Ardenska, Atanaska
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DIGITAL image processing ,MESSAGE passing (Computer science) ,IMAGE intensifiers ,COMPUTER systems ,INFORMATION processing - Abstract
As a popular linear filter, the mean filter is widely used in different applications as a basic tool for image enhancement. Its main purpose is to reduce the noise in an image and thus to prepare the picture for other image-processing operations depending on the current task. In the last decade, the amount of data, particularly images, that has to be processed in a variety of applications has increased significantly, and thus the usage of effective and fast filtering algorithms has become crucial. The aim of the present research is to identify what type of software (MATLAB, Scilab, or MPI-based) is preferred for reducing the filtering time and consequently save energy. Thus, the aim of the present research corresponds to actual trends in information processing and corresponds to green computing concepts. A set of experimental images divided into two groups—one for small images and a second one for big images—is used for performance evaluation of the recursive mean filter. This type of linear filter was chosen due to its very good denoising characteristics. The filter is implemented in MATLAB and Scilab environments using their specific commands and it is also implemented using the C language with the MPI library to provide the opportunity for parallel execution. Two mobile computer systems are used for experimental performance evaluation and the results indicate that the slowest filtering execution is registered when Scilab is used and the fastest execution is achieved when MPI is used with the C implementation. Depending on the amount and size of the images that have to be filtered, this study formulates advice for achieving effective performance throughout the whole process of working with images. [ABSTRACT FROM AUTHOR]
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- 2024
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20. Impact on cardiovascular outcome of coronary revascularization-induced changes in ischemic perfusion defect and myocardial flow reserve.
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Assante, Roberta, Zampella, Emilia, D'Antonio, Adriana, Mannarino, Teresa, Gaudieri, Valeria, Nappi, Carmela, Arumugam, Parthiban, Panico, Mariarosaria, Buongiorno, Pietro, Petretta, Mario, Cuocolo, Alberto, and Acampa, Wanda
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MYOCARDIAL perfusion imaging , *POSITRON emission tomography , *PERFUSION , *MYOCARDIAL infarction , *BLOOD flow , *HEART failure - Abstract
Purpose: We evaluated the impact on cardiovascular outcome of coronary revascularization-induced changes in ischemic total perfusion defect (ITPD) and myocardial flow reserve (MFR) as assessed by 82Rb positron emission tomography (PET)/computed tomography (CT) imaging. Methods: The study included 102 patients referred to 82Rb PET/CT myocardial perfusion imaging before and after coronary revascularization. All patients were followed for the occurrence of cardiovascular events (cardiac death, nonfatal myocardial infarction, repeated revascularization, and heart failure) after the second imaging study. Results: During a median follow-up of 20 months, 21 events occurred. The clinical characteristics were comparable between patients with and without events. In the overall study population, after revascularization, there was a significant reduction (P < 0.001) of ITPD, while hyperemic myocardial blood flow (MBF) (P < 0.01) and MFR (P < 0.05) significantly improved. Event rate was higher in patients with ITPD (P < 0.005) or MFR (P < 0.001) worsening compared to those with unchanged or improved ITPD or MFR. At Cox univariable analysis, ITPD and MFR worsening resulted in predictors of events (both P < 0.05). Patients with worsening of both ITPD and MFR had the worst event-free survival (log-rank 32.9, P for trend < 0.001). Conclusions: In patients with stable CAD, worsening of ITPD and MFR after revascularization procedures is associated with higher risk of cardiovascular events. Follow-up MPI with 82Rb PET/CT may improve risk stratification in patients submitted to coronary revascularization. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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21. Ventricular Functions in Congenital Heart Diseases: A Tissue Doppler Study.
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Raouf El Sharawy, Sahar Abd El, Khalifa, Naglaa Ali, Ahmed El Lithy, Eman Mohamed, and uzeid, Heba Abo
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CONGENITAL heart disease , *VENTRICULAR septum , *DOPPLER echocardiography , *PULMONARY artery , *RIGHT ventricular dysfunction - Abstract
Background: Congenital heart diseases (CHD) account for one third of all congenital anomalies. Doppler and Tissue Doppler evaluate cardiac performance and diagnose CHD. Study aim: evaluation ventricular functions in congenital heart diseases using tricuspid plane systolic excursion TAPSI and tissue Doppler-derived left ventricular myocardial performance index MPI. Methods: The study was performed at Pediatric Cardiology Unit of Zagazig University Hospitals on 70 age and sex matched children classified into case group included 35 patients with CHD and control group included 35 healthy children underwent complete history, conventional echocardiographic and tissue Doppler examination. Results: There was increase in cases regarding interventricular septum (IVS) and decrease in left ventricular diameter at end diastole (LVDd), left ventricular diameter at end systole (LVDs), right pulmonary artery diameter (RPA) and left atrium diameter more than control group with no difference in between regarding: posterior wall diameter (PW), fractional shortening (FS), main pulmonary artery diameter, left pulmonary artery diameter (LPA) and aorta diameter. There was a highly significant decrease in TAPSE in case more than control group and significant decrease in ejection time (ET) with no significant difference between case and control group regarding LV MPI. Conclusions: TAPSE is lower in cases compared with control group indicating longitudinal RV dysfunction. The value of LV MPI was slightly higher than that of control that need further studies with a larger number of patients.LV FS did not show any abnormality in cases pointing out ability of tissue Doppler echocardiography to measure segmental LV dysfunction compared to conventional echocardiography. [ABSTRACT FROM AUTHOR]
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- 2024
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22. An overview of the Legio fault resilience framework for MPI applications.
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Rocco, Roberto, Boella, Elisabetta, Gregori, Daniele, and Palermo, Gianluca
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FAULT tolerance (Engineering) ,BASIC needs ,EXPERTISE ,EXECUTIONS & executioners - Abstract
While the computational power of HPC clusters breached through the exascale milestone, it highlighted the need for some critical features like fault management. The current de facto standard for inter-process communication at scale, MPI, lacks proper fault management functionalities, precluding result production in the presence of faults. Many efforts have already addressed the problem, with the ULFM extension and Reinit proposal being the two works receiving the most attention. While powerful and effective, they require expertise from the user and significantly impact the application code. For this reason, we presented the Legio fault resilience framework, which can introduce graceful degradation properties in MPI applications with minimal changes. This work summarises the development and evolution of Legio, highlighting successful use cases and providing some tips for users who want to leverage it for their executions. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
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23. Not all applications have boring communication patterns: Profiling message matching with BMM
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Groves, Taylor, Ravichandrasekaran, Naveen, Cook, Brandon, Keen, Noel, Trebotich, David, Wright, Nicholas J, Alverson, Bob, Roweth, Duncan, and Underwood, Keith
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message matching ,MPI ,offload NIC ,tag matching ,Artificial Intelligence and Image Processing ,Computer Software ,Distributed Computing - Abstract
Message matching within MPI is an important performance consideration for applications that utilize two-sided semantics. In this work, we present an instrumentation of the CrayMPI library that allows the collection of detailed message-matching statistics as well as an implementation of hashed matching in software. We use this functionality to profile key DOE applications with complex communication patterns to determine under what circumstances an application might benefit from hardware offload capabilities within the NIC to accelerate message matching. We find that there are several applications and libraries that exhibit sufficiently long match list lengths to motivate a Binned Message Matching approach.
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- 2023
24. Premorbid frailty, stress hyperglycemia ratio, and functional outcome in patients with acute ischemic stroke
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Marialuisa Zedde, Simona Lattanzi, Andrea Pilotto, Daniel Janitschke, Jakob Stögbauer, Fatma Merzou, Rosario Pascarella, Alessandro Padovani, Andrea Morotti, and Piergiorgio Lochner
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SHR ,frailty ,stroke ,IVT ,MPI ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
BackgroundFrailty, defined as multidimensional prognostic index (MPI), has been recently identified as strong predictor of disability and mortality in the elderly with acute ischemic stroke (AIS). The stress hyperglycemia ratio (SHR) is a recently introduced biomarker significantly associated with poor outcome in AIS.ObjectivesThis study aimed to investigate in what extent frailty, measured by MPI, and SHR affects the 3-months outcome of patients > 65 years-old with AIS.MethodsConsecutive patients with AIS >65 years-old who underwent intravenous thrombolysis (IVT) from 2015 to 2019 were enrolled in a German and an Italian Stroke Unit. The SHR was calculated by dividing the fasting plasma glucose at admission with glycated hemoglobin. Demographics and clinical premorbid data, stroke-related variables, including baseline and post-treatment NIHSS score were included in a logistic regression model. The 3-months functional outcome was evaluated by using modified Rankin scale (mRS); good outcome was defined as mRS 0–2, poor as mRS ≥ 3.ResultsOne hundred and fifty-five AIS patients were enrolled in the study. Median MPI was 0.19 [0.13–0.31]; 118 (76.1%) patients were classified as “robust” and 37 (23.9%) as “frail.” In regression analysis, age, NIHSS, and MPI demonstrated as the most significant predictor of 3-months good outcome in the whole cohort. In robust patients, SHR values were significantly associated with the outcome.ConclusionsMPI is associated with the 3-months outcome in our cohort, in particular with good outcome. Conversely, SHR seems to be associated with a 3-months poor outcome in “robust” patients but not in frail patients.
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- 2024
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25. Open-loop narrowband magnetic particle imaging based on mixed-frequency harmonic magnetization response
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Hongli Yu, Ping Huang, Xiting Peng, Zheyan Wang, Zhichuan Qiu, Kewen Li, Tianshu Li, Zhiyao Liu, Hao Cui, and Shi Bai
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MPI ,SNR ,superparamagnetic nanoparticles ,mixed-frequency harmonic magnetization response ,narrowband ,Medical technology ,R855-855.5 - Abstract
IntroductionMagnetic particle imaging (MPI), a radiation-free, dynamic, and targeted imaging technique, has gained significant traction in both research and clinical settings worldwide. Signal-to-noise ratio (SNR) is a crucial factor influencing MPI image quality and detection sensitivity, and it is affected by ambient noise, system thermal noise, and the magnetization response of superparamagnetic nanoparticles. Therefore to address the high amplitude system and inherent thermal noise present in conventional MPI systems is essential to improve detection sensitivity and imaging resolution.MethodThis study introduces a novel open-loop, narrow-band MPI signal acquisition system based on mixed-frequency harmonic magnetization response. Allowing superparamagnetic nanoparticles to be excited by low frequency, high amplitude magnetic fields and high frequency, low amplitude magnetic fields, the excitation coil generates a mixed excitation magnetic field at a mixed frequency of 8.664 kHz (fH + 2fL), and the tracer of superparamagnetic nanoparticles can generate a locatable superparamagnetic magnetization signal with rich harmonic components in the mixed excitation magnetic field and positioning magnetic field. The third harmonic signal is detected by a Gradiometer coil with high signal-to-noise ratio, and the voltage cloud image is formed.ResultThe experimental results show that the external noise caused by the excitation coil can be effectively reduced from 12 to about 1.5 μV in the imaging area of 30 mm × 30 mm, which improves the stability of the detection signal of the Gradiometer coil, realizes the detection of high SNR, and makes the detection sensitivity reach 10 μg Fe. By mixing excitation, the total intensity of the excitation field is reduced, resulting in a slight improvement of the resolution under the same gradient field, and the spatial resolution of the image reconstruction is increased from 2 mm under the single frequency excitation (20.7 kHz) in the previous experiment to 1.5 mm under the mixed excitation (8.664 kHz).ConclusionsThese experimental results highlight the effectiveness of the proposed open-loop narrowband MPI technique in improving signal detection sensitivity, achieving high signal-to-noise ratio detection and improving the quality of reconstructed images by changing the excitation magnetic field frequency of the excitation coil, providing novel design ideas and technical pathways for future MPI systems.
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- 2024
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26. Towards a Scalable and Efficient PGAS-Based Distributed OpenMP
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Shan, Baodi, Araya-Polo, Mauricio, Chapman, Barbara, Goos, Gerhard, Series Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Espinosa, Alexis, editor, Klemm, Michael, editor, de Supinski, Bronis R., editor, Cytowski, Maciej, editor, and Klinkenberg, Jannis, editor
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- 2024
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27. PET Myocardial Perfusion Imaging: 82Rb
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De Rimini, Maria Luisa, Borrelli, Giovanni, Calabria, Ferdinando, editor, and Schillaci, Orazio, editor
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- 2024
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28. MPR: An MPI Framework for Distributed Self-adaptive Stream Processing
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Löff, Júnior, Griebler, Dalvan, Fernandes, Luiz Gustavo, Binder, Walter, Goos, Gerhard, Series Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Carretero, Jesus, editor, Shende, Sameer, editor, Garcia-Blas, Javier, editor, Brandic, Ivona, editor, Olcoz, Katzalin, editor, and Schreiber, Martin, editor
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- 2024
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29. Collective Contracts for Message-Passing Parallel Programs
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Luo, Ziqing, Siegel, Stephen F., Goos, Gerhard, Series Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Gurfinkel, Arie, editor, and Ganesh, Vijay, editor
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- 2024
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30. Teaching High–performance Computing Systems – A Case Study with Parallel Programming APIs: MPI, OpenMP and CUDA
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Czarnul, Pawel, Matuszek, Mariusz, Krzywaniak, Adam, Hartmanis, Juris, Founding Editor, van Leeuwen, Jan, Series Editor, Hutchison, David, Editorial Board Member, Kanade, Takeo, Editorial Board Member, Kittler, Josef, Editorial Board Member, Kleinberg, Jon M., Editorial Board Member, Kobsa, Alfred, Series Editor, Mattern, Friedemann, Editorial Board Member, Mitchell, John C., Editorial Board Member, Naor, Moni, Editorial Board Member, Nierstrasz, Oscar, Series Editor, Pandu Rangan, C., Editorial Board Member, Sudan, Madhu, Series Editor, Terzopoulos, Demetri, Editorial Board Member, Tygar, Doug, Editorial Board Member, Weikum, Gerhard, Series Editor, Vardi, Moshe Y, Series Editor, Goos, Gerhard, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Woeginger, Gerhard, Editorial Board Member, Franco, Leonardo, editor, de Mulatier, Clélia, editor, Paszynski, Maciej, editor, Krzhizhanovskaya, Valeria V., editor, Dongarra, Jack J., editor, and Sloot, Peter M. A., editor
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- 2024
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31. Parallel-EvoCluster: An Open-Source Parallel Nature-Inspired Optimization Clustering
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Alvarez-Mamani, Edwin, Yarahuaman-Rojas, Milagros, Huillca-Huallparimachi, Raul, Filipe, Joaquim, Editorial Board Member, Ghosh, Ashish, Editorial Board Member, Zhou, Lizhu, Editorial Board Member, Lossio-Ventura, Juan Antonio, editor, Ceh-Varela, Eduardo, editor, Vargas-Solar, Genoveva, editor, Marcacini, Ricardo, editor, Tadonki, Claude, editor, Calvo, Hiram, editor, and Alatrista-Salas, Hugo, editor
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- 2024
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32. MPI4All: Universal Binding Generation for MPI Parallel Programming
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Piñeiro, César, Vazquez, Alvaro, Pichel, Juan C., Hartmanis, Juris, Founding Editor, van Leeuwen, Jan, Series Editor, Hutchison, David, Editorial Board Member, Kanade, Takeo, Editorial Board Member, Kittler, Josef, Editorial Board Member, Kleinberg, Jon M., Editorial Board Member, Kobsa, Alfred, Series Editor, Mattern, Friedemann, Editorial Board Member, Mitchell, John C., Editorial Board Member, Naor, Moni, Editorial Board Member, Nierstrasz, Oscar, Series Editor, Pandu Rangan, C., Editorial Board Member, Sudan, Madhu, Series Editor, Terzopoulos, Demetri, Editorial Board Member, Tygar, Doug, Editorial Board Member, Weikum, Gerhard, Series Editor, Vardi, Moshe Y, Series Editor, Goos, Gerhard, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Woeginger, Gerhard, Editorial Board Member, Franco, Leonardo, editor, de Mulatier, Clélia, editor, Paszynski, Maciej, editor, Krzhizhanovskaya, Valeria V., editor, Dongarra, Jack J., editor, and Sloot, Peter M. A., editor
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- 2024
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33. ExaNBody: A HPC Framework for N-Body Applications
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Carrard, Thierry, Prat, Raphaël, Latu, Guillaume, Babilotte, Killian, Lafourcade, Paul, Amarsid, Lhassan, Soulard, Laurent, Goos, Gerhard, Founding Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Zeinalipour, Demetris, editor, Blanco Heras, Dora, editor, Pallis, George, editor, Herodotou, Herodotos, editor, Trihinas, Demetris, editor, Balouek, Daniel, editor, Diehl, Patrick, editor, Cojean, Terry, editor, Fürlinger, Karl, editor, Kirkeby, Maja Hanne, editor, Nardelli, Matteo, editor, and Di Sanzo, Pierangelo, editor
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- 2024
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34. Algorithm Selection of MPI Collectives Considering System Utilization
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Salimi Beni, Majid, Hunold, Sascha, Cosenza, Biagio, Goos, Gerhard, Founding Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Zeinalipour, Demetris, editor, Blanco Heras, Dora, editor, Pallis, George, editor, Herodotou, Herodotos, editor, Trihinas, Demetris, editor, Balouek, Daniel, editor, Diehl, Patrick, editor, Cojean, Terry, editor, Fürlinger, Karl, editor, Kirkeby, Maja Hanne, editor, Nardelli, Matteo, editor, and Di Sanzo, Pierangelo, editor
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- 2024
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35. Optimization, Performance and Scalability Experiments of a Large Air Pollution Model by Using the EuroHPC Petascale Supercomputer DISCOVERER
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Ostromsky, Tzvetan, Kacprzyk, Janusz, Series Editor, and Fidanova, Stefka, editor
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- 2024
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36. Performance Evaluation of Spark, Ray and MPI: A Case Study on Long Read Alignment Algorithm
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Ran, Kun, Cui, Yingbo, Wang, Zihang, Peng, Shaoliang, Goos, Gerhard, Founding Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Tari, Zahir, editor, Li, Keqiu, editor, and Wu, Hongyi, editor
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- 2024
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37. The Implementation and Optimization of FFT Calculation Based on the MT-3000 Chip
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Cheng, Dong, Li, Guilan, Song, Aochuang, Xu, Bangjian, Filipe, Joaquim, Editorial Board Member, Ghosh, Ashish, Editorial Board Member, Prates, Raquel Oliveira, Editorial Board Member, Zhou, Lizhu, Editorial Board Member, Cruz, Christophe, editor, Zhang, Yanchun, editor, and Gao, Wanling, editor
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- 2024
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38. Parallel Programming in the Hybrid Model on the HPC Clusters
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Rak, Tomasz, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Tan, Kay Chen, Series Editor, Malhotra, Ruchika, editor, Sumalatha, L., editor, Yassin, S. M. Warusia, editor, Patgiri, Ripon, editor, and Muppalaneni, Naresh Babu, editor
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- 2024
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39. Using MPIs Non-Blocking Allreduce for Health Checks in Dynamic Simulations
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Gericke, Jana, Klimach, Harald, Ebrahimi Pour, Neda, Roller, Sabine, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Tan, Kay Chen, Series Editor, Park, Ji Su, editor, Takizawa, Hiroyuki, editor, Shen, Hong, editor, and Park, James J., editor
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- 2024
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40. Comparative analysis of the rapid intensification of two super cyclonic storms in the Arabian Sea
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Longsheng Liu, Yiwu Huang, and Lian Liu
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Super cyclonic storm ,Rapid intensification ,Upper-level outflow ,Potential vorticity ,MPI ,Physical geography ,GB3-5030 ,Environmental sciences ,GE1-350 - Abstract
A comparative analysis of the rapid intensification (RI) of super cyclonic storms Chapala (2015) and Kyarr (2019) in the Arabian Sea is conducted using the North Indian Ocean tropical cyclone data, microwave sounding images, the NOAA OISST data and the ERA5 reanalysis data. Results show that the subtropical westerly jet stream and the Southern Hemisphere anticyclonic circulation led to the formation of an obvious double-channel outflow from the northern and southern sides of the two storm centers, and the substantial inflow appeared at the eastern boundary layer of both storms. These promoted the vertical ascent motion and release of the latent heat of condensation. A warm sea surface is a necessary but not dominant factor for the RI of cyclonic storms in the Arabian Sea. During the RI of Chapala and Kyarr, the deep vertical wind shear was less than 10 m s−1; moreover, the mid-level humidity conditions favored the RI of the two cyclonic storms. Chapala had a single warm core, whereas Kyarr had double warm cores in the vertical direction. The impacts of the latent heat of fusion is more obvious for Chapala, and the potential vorticity in its inner core increases from 4.4 PVU to 8.8 PVU, whereas the potential vorticity and vorticity in the inner core of Kyarr do not change significantly. Microwave detection images show that both Chapala and Kyarr were accompanied by the formation of eyewalls during the RI phase, and the radius of maximum wind decreased and the maximum wind speed increased during the eyewall-thinning process. Both Chapala and Kyarr passed through a positive anomaly region of maximum potential intensity during the RI phase, which increases the possibility to develop to higher intensity after genesis.
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- 2024
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41. Numba-MPI v1.0: Enabling MPI communication within Numba/LLVM JIT-compiled Python code
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Kacper Derlatka, Maciej Manna, Oleksii Bulenok, David Zwicker, and Sylwester Arabas
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Python ,MPI ,Numba ,JIT ,Multi-threading ,LLVM ,Computer software ,QA76.75-76.765 - Abstract
The numba-mpi package offers access to the Message Passing Interface (MPI) routines from Python code that uses the Numba just-in-time (JIT) compiler. As a result, high-performance and multi-threaded Python code may utilize MPI communication facilities without leaving the JIT-compiled code blocks, which is not possible with the mpi4py package, a higher-level Python interface to MPI. For debugging or code-coverage analysis purposes, numba-mpi retains full functionality of the code even if the JIT compilation is disabled. The numba-mpi API constitutes a thin wrapper around the C API of MPI and is built around Numpy arrays including handling of non-contiguous views over array slices. Project development is hosted at GitHub leveraging the mpi4py/setup-mpi workflow enabling continuous integration tests on Linux (MPICH, OpenMPI & Intel MPI), macOS (MPICH & OpenMPI) and Windows (MS MPI). The paper covers an overview of the package features, architecture and performance. As of v1.0, the following MPI routines are exposed and covered by unit tests: size/rank, [i]send/[i]recv, wait[all|any], test[all|any], allreduce, bcast, barrier, scatter/[all]gather & wtime. The package is implemented in pure Python and depends on numpy, numba and mpi4py (the latter used at initialization and as a source of utility routines only). The performance advantage of using numba-mpi compared to mpi4py is depicted with a simple example, with entirety of the code included in listings discussed in the text. Application of numba-mpi for handling domain decomposition in numerical solvers for partial differential equations is presented using two external packages that depend on numba-mpi: py-pde and PyMPDATA-MPI.
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- 2024
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42. MPI+CUDA联合加速重力场反演的并行算法.
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赵锴坤, 朱炬波, 谷德峰, and 韦春博
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Copyright of Journal of Geodesy & Geodynamics (1671-5942) is the property of Editorial Board Journal of Geodesy & Geodynamics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2024
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43. Temporal-Logic-Based Testing Tool Architecture for Dual-Programming Model Systems.
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Saad, Salwa, Fadel, Etimad, Alzamzami, Ohoud, Eassa, Fathy, and Alghamdi, Ahmed M.
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C++ ,LOGIC design ,MESSAGE passing (Computer science) ,PROGRAMMING languages ,SYSTEMS software - Abstract
Today, various applications in different domains increasingly rely on high-performance computing (HPC) to accomplish computations swiftly. Integrating one or more programming models alongside the used programming language enhances system parallelism, thereby improving its performance. However, this integration can introduce runtime errors such as race conditions, deadlocks, or livelocks. Some of these errors may go undetected using conventional testing techniques, necessitating the exploration of additional methods for enhanced reliability. Formal methods, such as temporal logic, can be useful for detecting runtime errors since they have been widely used in real-time systems. Additionally, many software systems must adhere to temporal properties to ensure correct functionality. Temporal logics indeed serve as a formal frame that takes into account the temporal aspect when describing changes in elements or states over time. This paper proposes a temporal-logic-based testing tool utilizing instrumentation techniques designed for a dual-level programming model, namely, Message Passing Interface (MPI) and Open Multi-Processing (OpenMP), integrated with the C++ programming language. After a comprehensive study of temporal logic types, we found and proved that linear temporal logic is well suited as the foundation for our tool. Notably, while the tool is currently in development, our approach is poised to effectively address the highlighted examples of runtime errors by the proposed solution. This paper thoroughly explores various types and operators of temporal logic to inform the design of the testing tool based on temporal properties, aiming for a robust and reliable system. [ABSTRACT FROM AUTHOR]
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- 2024
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44. Graphical Representation of Multidimensional Poverty: Insights for Index Construction and Policy Making.
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García Arancibia, Rodrigo and Girela, Ignacio
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ISING model , *UNDIRECTED graphs , *POVERTY , *POVERTY areas , *RANDOM fields , *PROBABILISTIC databases - Abstract
By means of probabilistic graphical models, in this paper, we present a new framework for exploring relationships among indicators commonly included in the Multidimensional Poverty Index (MPI). In particular, we propose an Ising model with covariates for modeling the MPI as an undirected graph. First, we prove why Ising models are consistent with the theoretical distribution of MPI indicators. Then, a comparison between our estimates and the association measures typically used in the literature is provided. Finally, we show how undirected graphs can complement the MPI policy-relevant properties, apart from discovering further insightful patterns that can be useful for policy purposes. This novel approach is illustrated with an empirical application for the global MPI indicators of Guinea and Ecuador, taking living areas and monetary poverty as covariates, respectively. [ABSTRACT FROM AUTHOR]
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- 2024
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45. PeriLab — Peridynamic Laboratory
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Christian Willberg, Jan-Timo Hesse, and Anna Pernatii
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Peridynamics ,Fracture ,HPC ,Computational science ,MPI ,Julia ,Computer software ,QA76.75-76.765 - Abstract
This paper introduces PeriLab, a modern Peridynamics solver developed in the Julia programming language. Emphasizing easy installation, usability, and implementation of new features, the code’s structure is detailed, accompanied by illustrative examples illustrating some of the code’s core functionality. The fully Message Passing Interface (MPI) parallelized code undergoes a separate benchmark problem with two million degrees of freedom, revealing large scale capabilities and analyzing the communication cost occurring in such analysis. The paper highlights key considerations for the adoption of Peridynamics, including the need for a straightforward installation process, user-friendly interfaces, efficient research code development, and well-documented as well as tested functionalities. Overcoming these challenges is crucial for Peridynamics’ widespread acceptance in engineering applications, and PeriLab serves as a valuable contribution to addressing these issues.
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- 2024
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46. Low-Power Scalable TSPI: A Modular Off-Chip Network for Edge AI Accelerators
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Seunghyun Park and Daejin Park
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TSPI ,off-chip network ,edge device ,subset mapping algorithm ,low power ,MPI ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
In this paper, we present a novel off-chip network architecture, the Tile Serial Peripheral Interface (TSPI), designed for low-power, scalable edge AI accelerators. Our approach modifies the conventional SPI to support a modular network structure that facilitates the scalable connection of multiple accelerators. The TSPI network employs a subset mapping algorithm for efficient routing and integrates the message passing interface (MPI) protocol to ensure rapid data distribution and aggregation. This modular architecture significantly reduces power consumption and improves processing speed. Experimental results demonstrate that our proposed TSPI network achieves a 54.7% reduction in power consumption and an 82.3% decrease in switching power compared to traditional SPI networks, along with a 23% increase in processing speed when utilizing 16 nodes. These advancements make the TSPI network an effective solution for enhancing AI performance in edge computing environments.
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- 2024
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47. Glucose-Regulated Protein 78 Targeting ICG and DOX Loaded Hollow Fe3O4 Nanoparticles for Hepatocellular Carcinoma Diagnosis and Therapy
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Jin Y, Cheng Z, Yuan Z, Du Y, Tian J, and Shao B
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porous hollow structure ,magnetic particle imaging ,mpi ,fluorescence imaging ,synergistic treatment ,theranostics ,Medicine (General) ,R5-920 - Abstract
Yushen Jin,1 Zhongquan Cheng,2 Zhu Yuan,2 Yang Du,3 Jie Tian,3 Bing Shao1,4 1Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Centre for Disease Prevention and Control, Beijing, 100013, People’s Republic of China; 2Department of General Surgery, Capital Medical University, Beijing Friendship Hospital, Beijing, 100050, People’s Republic of China; 3CAS Key Laboratory of Molecular Imaging, Key Laboratory of Molecular Imaging, Institute of Automation, Chinese Academy of Sciences, Beijing, 100190, People’s Republic of China; 4College of Veterinary Medicine, China Agricultural University, Beijing, 100193, People’s Republic of ChinaCorrespondence: Bing Shao; Jie Tian, Email shaobingch@sina.com; jietian@ia.ac.cnPurpose: Liver cancer is considered as the third leading cause of cancer-related deaths, with hepatocellular carcinoma (HCC) accounting for approximately 90% of liver cancers. Improving the treatment of HCC is a serious challenge today. The primary objective of this study was to construct SP94-Fe3O4@ICG&DOX nanoparticles and investigate their potential diagnosis and treatment effect benefits on HCC.Methods: Firstly, we synthesized and characterized SP94-Fe3O4@ICG&DOX nanoparticles and confirmed their in vitro release behavior, photothermal and photodynamic performance. Moreover, the in vivo imaging capability was also observed. Finally, the inhibitory effects on Hepa1-6 in vitro and in vivo were observed as well as biosafety.Results: SP94-Fe3O4@ICG&DOX nanoparticles have a size of ~22.1 nm, with an encapsulation efficiency of 45.2% for ICG and 42.7% for DOX, showing excellent in vivo MPI and fluorescence imaging capabilities for precise tumor localization, and synergistic photo-chemotherapy (pH- and thermal-sensitive drug release) against tumors under irradiation. With the assistance of a fluorescence molecular imaging system or MPI scanner, the location and contours of the tumor were clearly visible. Under a constant laser irradiation (808 nm, 0.6 W/cm2) and a set concentration (50 μg/mL), the temperature of the solution could rapidly increase to ~45 °C, which could effectively kill the tumor cells. It could be effectively uptaken by HCC cells and significantly inhibit their proliferation under the laser irradiation (100% inhibition rate for HCC tumors). And most importantly, our nanoparticles exhibited favorable biocompatibility with normal tissues and cells.Conclusion: This versatile agent can serve as an intelligent and promising nanoplatform that integrates multiple accurate diagnoses, precise positioning of cancer tissue, and effective coordination with synergistic tumor photodynamic therapy. Keywords: porous hollow structure, magnetic particle imaging, fluorescence imaging, synergistic treatment, theranostics
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- 2024
48. Inter-Node Message Passing Through Optical Reconfigurable Memory Channel
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Mauricio G. Palma, Jorge Gonzalez, Martin Carrasco, Ruth Rubio-Noriega, Keren Bergman, and Rodolfo Azevedo
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Inter-node message passing ,MPI ,message passing ,optical interconnection ,photonic ,disaggregated memory ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
Efficient data movement between nodes in a data center is essential for optimal performance of distributed workloads. With advancements in computing interconnection and memory, new opportunities have emerged. We propose a novel inter-node architecture and protocol called Flexible Memory Units (FMU) that uses optically disaggregated memory. FMUs can be dynamically allocated to different nodes during runtime using optical switches. The primary objective of FMUs is to use the disaggregated memory as temporary buffers during inter-node communication. We have implemented Simplecomm, an open-source simulator, to evaluate real MPI benchmarks using FMU. Our evaluation demonstrates significant speedups of up to $5.18\times $ in communication-bound applications and $1.22\times $ on computing-intensive applications, compared to a 100 Gbps InfiniBand interconnect.
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- 2024
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49. Comparative Analysis of OpenMP and MPI Parallel Computing Implementations in Team Sort Algorithm
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Eko Dwi Nugroho, Ilham Firman Ashari, Muhammad Nashrullah, Muhammad Habib Algifari, and Miranti Verdiana
- Subjects
mpi ,openmp ,parallel computation ,parallelization ,team sort algorithm ,Electronic computers. Computer science ,QA75.5-76.95 - Abstract
Tim Sort is a sorting algorithm that combines Merge Sort and Binary Insertion Sort sorting algorithms. Parallel computing is a computational processing technique in parallel or is divided into several parts and carried out simultaneously. The application of parallel computing to algorithms is called parallelization. The purpose of parallelization is to reduce computational processing time, but not all parallelization can reduce computational processing time. Our research aims to analyse the effect of implementing parallel computing on the processing time of the Tim Sort algorithm. The Team Sort algorithm will be parallelized by dividing the flow or data into several parts, then each sorting and recombining them. The libraries we use are OpenMP and MPI, and tests are carried out using up to 16 core processors and data up to 4194304 numbers. The goal to be achieved by comparing the application of OpenMP and MPI to the Team Sort algorithm is to find out and choose which library is better for the case study, so that when there is a similar case, it can be used as a reference for using the library in solving the problem. The results of research for testing using 16 processor cores and the data used prove that the parallelization of the Sort Team algorithm using OpenMP is better with a speed increase of up to 8.48 times, compared to using MPI with a speed increase of 8.4 times. In addition, the increase in speed and efficiency increases as the amount of data increases. However, the increase in efficiency that is obtained by increasing the processor cores decreases.
- Published
- 2023
- Full Text
- View/download PDF
50. Performance Evaluation of Recursive Mean Filter Using Scilab, MATLAB, and MPI (Message Passing Interface)
- Author
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Hristina Andreeva and Atanaska Bosakova-Ardenska
- Subjects
digital image processing ,Scilab ,MATLAB ,MPI ,multi-core architectures ,Engineering machinery, tools, and implements ,TA213-215 - Abstract
As a popular linear filter, the mean filter is widely used in different applications as a basic tool for image enhancement. Its main purpose is to reduce the noise in an image and thus to prepare the picture for other image-processing operations depending on the current task. In the last decade, the amount of data, particularly images, that has to be processed in a variety of applications has increased significantly, and thus the usage of effective and fast filtering algorithms has become crucial. The aim of the present research is to identify what type of software (MATLAB, Scilab, or MPI-based) is preferred for reducing the filtering time and consequently save energy. Thus, the aim of the present research corresponds to actual trends in information processing and corresponds to green computing concepts. A set of experimental images divided into two groups—one for small images and a second one for big images—is used for performance evaluation of the recursive mean filter. This type of linear filter was chosen due to its very good denoising characteristics. The filter is implemented in MATLAB and Scilab environments using their specific commands and it is also implemented using the C language with the MPI library to provide the opportunity for parallel execution. Two mobile computer systems are used for experimental performance evaluation and the results indicate that the slowest filtering execution is registered when Scilab is used and the fastest execution is achieved when MPI is used with the C implementation. Depending on the amount and size of the images that have to be filtered, this study formulates advice for achieving effective performance throughout the whole process of working with images.
- Published
- 2024
- Full Text
- View/download PDF
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