Academic literature on the topic 'Standard MPI-2 RMA'

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Journal articles on the topic "Standard MPI-2 RMA"

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Hu, Yulan, Dagang Liu, Laqun Liu, Huihui Wang, and Qiang Li. "Research on parallel algorithm of high-power microwave devices simulation based on MPI-3." AIP Advances 12, no. 7 (July 1, 2022): 075313. http://dx.doi.org/10.1063/5.0094850.

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Simulation of high-power microwave source devices generally uses parallel algorithms to speed up the operation. In recent years, with the upgrade of parallel technology, the parallel efficiency of the particle simulation software has been further improved. Existing MPI-2 parallel technology of particle simulation software CHIPIC realizes the access to the local memory space of other processes through message passing. The new version of the MPI-3 standard provides the shared memory feature, which allows the data to be directly called by each process in the shared memory window, which reduces the information transmission. In this paper, based on the shared memory feature of MPI-3, the electromagnetic particle simulation parallel algorithm and dynamic load balancing algorithm are designed in the particle simulation software. The implementation of the two algorithms can improve the parallel efficiency from different aspects. The RKA and magnetic isolation oscillator high-power microwave devices are used as the test models. The test results show that the electromagnetic particle simulation parallel algorithm based on the shared memory feature of MPI-3 can improve the efficiency of the software by up to 44%. The efficiency of the dynamic load balancing algorithm based on MPI-3 can also be improved by up to 38%.
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Majumder, Sanhita, Shamim Momtaz Ferdousi Begum, Ankan Kumar Paul, and Chayan Singha. "Myocardial Perfusion Imaging in the Evaluation of Outcome of Coronary Intervention in Coronary Artery Disease Patients." Bangladesh Journal of Nuclear Medicine 22, no. 1 (December 11, 2019): 23–29. http://dx.doi.org/10.3329/bjnm.v22i1.40500.

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Background: Coronary artery disease (CAD) is an important medical and public health issue because it is one of the leading causes of death and disability throughout the world and is rapidly emerging as a major cause of mortality in developing countries including Bangladesh. SPECT-MPI is a cost- effective and non invasive means of identifying ischemic and viable myocardium along with its vascular distribution. This study is aimed to evaluate prospectively the ability of MPI to predict the outcome of Coronary Intervention in CAD patients of Bangladesh who are referred to National Institute of Nuclear Medicine & Allied Sciences (NINMAS) for performing MPI. Patients and Methods: This prospective longitudinal and observational type of study was carried out in National Institute of Nuclear Medicine & Allied Sciences (NINMAS) located at Bangabandhu Sheikh Mujib Medical University (BSMMU) campus, from July 2017 to June 2018with 12 CAD patients who were referred here. Gated SPECT MPI was performed on the selected patients before any coronary intervention to predict myocardial viability & probable outcome of intervention. A follow up MPI of the same patients was performed after minimum 3 to 4 months of revascularization procedure to determine the outcome of intervention and to detect in stent restenosis or new onset ischemia if present which can be prevented by additional revascularization procedure. Finally pre and post intervention MPI results were analyzed by standard statistical analysis by using the Statistical Package for Social Sciences version 20.0 for Windows (SPSS Inc., Chicago, Illinois, USA). P values <0.05 was considered as statistically significant. Results: The sensitivity of MPI for the initial evaluation and risk stratification by diagnosing perfusion defect in the enrolled 12 CAD patients have been found to be 90%,77.8% and 81.8% in case of LAD, LCX and RCA territories respectively. Whereas the specificity and positive predictive value have been found 100% for LAD and RCA territories. About 16.67% patients were found to have restenosis in this study diagnosed by early post-intervention MPI. It was observed that majority of the patients had perfusion defect in LAD territory. 3(25.0%) patients had fixed defect, 5(41.7%) patients had partial reversible defect and 4(33.3%) patients had complete reversible defect in pre intervention MPI. In post intervention MPI, 4(33.3%) patients had partially reversible perfusion defect, 2(16.7%) patients had fixed perfusion defect, 1(3.3%) patient was found with completely reversible perfusion defect and 5(41.7%) patients had normal MPI findings. The result was found statistically significant (P value <0.05) in case of partially reversible perfusion defect and normal MPI findings when before and after intervention MPI results were compared. The difference of mean percentage of involved myocardium by fixed defect between pre and post intervention MPI was found statistically significant (P<0.05) in case of LAD territory and total LV myocardium involvement. 33.3% patients were in high risk before undergoing intervention, whereas it was found to be 25% after intervention which was calculated on the basis of their pre and post intervention SSS(Summed Stress Score) result. Conclusion: The results of this study have indicated that SPECT MPI provides significant independent information concerning the outcome of coronary intervention in CAD patients. Furthermore, early SPECT MPI after intervention successfully identified significant improvement of myocardial viability after revascularization in patients having complete or reversible perfusion defects found in pre intervention MPI along with identifying those having restenosis. It could also depict the reduction of percentage of myocardial fixed defects within 3-4 months after intervention which is also a positive outcome of coronary revascularization. Bangladesh J. Nuclear Med. 22(1): 23-29, Jan 2019
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AJWAD, Ali, Sameel AHMAD, ABDULLAH, Syed Taseer Abbas JAFFAR, Usman ILYAS, and Muhammad Ahmad ADNAN. "Effect of Using Rice Husk Ash as Partial Replacement of Cement on Properties of Fresh and Hardened Concrete." Architecture, Civil Engineering, Environment 15, no. 2 (June 1, 2022): 85–94. http://dx.doi.org/10.2478/acee-2022-0017.

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Abstract Rice husk disposal has become a great challenge for Pakistan being one of the largest rice producer across the globe. Rice Husk Ash (RHA) contains sufficient pozzolanic properties which opens up opportunities for its usage as cementitious material as partial replacement of Ordinary Portland Cement (OPC). In this research RHA was added as cement replacement in different percentages by weight of cement i.e. 0%, 6%, 12%, 18% and 24% at constant mix ratio of 1:2:4 and water-cement ratio of 0.6 that is M15 grade concrete with a target strength of 15-20 MPa. The properties of concrete like workability, compressive strength, tensile strength, flexure strength, and water permeability were investigated by casting standard concrete samples in the form of cubes, cylinders and beams in addition to cost comparison study The outcomes show that workability of fresh concrete increases with an increase in RHA content and almost all concrete properties studied in this research gave more favorable results at 6% replacement level compared with the control mix.
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Kalaw, Martin Ernesto L., Alvin B. Culaba, Hoc Thang Nguyen, Khoi Nguyen, Hirofumi Hinode, Winarto Kurniawan, Susan M. Gallardo, and Michael Angelo B. Promentilla. "Mechanical and Thermal Properties of Geopolymers from Mixtures of Coal Ash and Rice Hull Ash using Water Glass Solution as Activator." ASEAN Journal of Chemical Engineering 15, no. 2 (April 19, 2016): 51. http://dx.doi.org/10.22146/ajche.49686.

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Geopolymers, from industrial wastes such as blast furnace slag, red mud, and coal ash, among others, have emerged as technically viable, economically competitive, and environmentally attractive supplements and even alternatives to ordinary Portland cement (OPC). Furthermore, while the most impact shall be achieved with large-scale use in the general building and structural sector, as replacement or supplement to OPC, the properties of these geopolymers may be optimized for special niche applications. One of these applications is for light weight, low thermal conductivity, heat resistant, and moderate strength cement binder for low rise residential buildings. In this study, compressive strength, heat resistance, volumetric weight, mass loss, water absorption and thermal conductivity of geopolymers formed from mixtures of coal bottom ash and rice hull ash (CBA-RHA) and coal fly ash and rice hull ash (CFA-RHA) with sodium silicate solution (modulus 2.5) as activator were evaluated. Using mixture design and the JMP statistical software, the CBA-RHA combination at a mass ratio of 46% CBA, 32% RHA with 22% WGS gave properties at maximum desirability of 17.6 MPa compressive strength, 1640 kg/m3 volumetric weight, 273 kg/m3 water absorption, 28 MPa compressive strength after high temperature exposure (1000oC for 2 hours) with 4.4% mass loss, and 0.578 W/m-K thermal conductivity. On a performance basis, even as the geopolymers are formed as paste, these properties fall within the standards for lightweight OPC based-concrete with strength requirements for residential buildings. The low thermal conductivity and higher strength after high temperature exposure vis-à-vis OPC are additional advantages for consideration.
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Polk, D. F., F. C. Swift, and M. Cantarella. "Apple, Evaluation of Experimental Insecticide Ac-303630 24 Sc, 1991." Insecticide and Acaricide Tests 17, no. 1 (January 1, 1992): 35. http://dx.doi.org/10.1093/iat/17.1.35.

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Abstract Treatments were applied to 5 tree plots replicated 4 times in a randomized complete block design. The orchard block consisted of'Red Delicious' on Mill planted in 1970 on a 20' by 20' spacing. Sprays were applied with an FMC handgun sprayer using a 5 HP diaphragm pump at 280 psi until run off, with approx. 4 gal of spray applied to each tree. There were 5 treatments in this test; 1) = AC-303630 50.9 g AI/100 gal, 2) = AC-303630 101.8 g AI/100 gal, 3) = AC-303630 203.7 g AI/100 gal, 4) = Standard Program, and 5) = untreated control. The Standard Program consisted of: Pink—Thiodan 50 WP 454 g/100 gal, Petal Fall—Imidan 50 WP 454 g/100 gal + Carzol 92 SP 60 g/ 100 gal, 1st Cover—Imidan 454 g/100 gal, 2nd Cover—Imidan 454 g/100 gal + Lannate 1.8 L 235 ml/100 gal, 3rd Cover—Imidan 454 g/100 gal, 4th Cover— Imidan 454 g/100 gal, 5th Cover—Imidan 454 g/100 gal, and 6th Cover—Imidan 454 g/100 gal. Spray dates for all treatments and conditions were: Pink— 12 Apr 57°F, 2 mph wind & clear, Petal Fall—2 May 62°F, 0-2 mph wind & clear, 1st Cover—20 May 65°F, 0-2 mph wind & clear, 2nd Cover—10 Jun 85°F, 5 mph wind & clear, 3rd Cover—1 Jul 75°F 0-2 mph wind & cloudy, 4th Cover—17 Jul 83°F, 5 mph wind & clear, 5th Cover—6 Aug 75°F, 2-3 mph wind & clear, and 6th Cover—28 Aug 75°F, 0-2 mph wind & clear. All treatments received regular fungicide cover sprays of Captan or Captan + Rubigan. Mite and mite predator counts were done on a weekly basis, with each mite sample consisting of 25 leaves per tree, brushed and counted with a binocular scope. SP counts are reported as a 3 min count per tree. SJS counts were done on 1 Aug, and reported as the number damaged per 100 fruit per tree and as the number of sites present in the 20 maximally infested fruit per tree. AA counts were made on 6 Jun and 14 Jun. Data are reported as average aphis per colony of the 10 maximally infested colonies per tree. STLM, WALH, EAS, and RAA counts were done on 21 May. STLM counts are reported as mines per 3 min count per tree. WALH counts are reported as damaged leaves out of 300 leaves per tree. EAS counts are reported as infestations per 300 fruit. RAA counts are reported as colonies per tree. A post-harvest fruit evaluation was done, using 100 fruit per tree and reported as percent damage by AM, CM, EAS, PC, SJS, TABM/LR, and TPB. A postharvest fruit finish evaluation consisted of 30 fruit per tree. Each fruit was rated on a 0 to 5 scale for percent russet. Values used were as follows: 0 = no russet, I = raised lenticels, 2 = 1-10% russeted, 3 = 11-15% russeted, 4 = 16-50% russeted, and 5 = &gt;51% russeted. Mean values of each replicate were used for calculations. Data were transformed to log(x + 1) for analysis at P = 0.01 except on the 15 Jul mite count where P = 0.05.
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Long, Hoang Vinh. "Optimizing Mixtures of Alkali Aluminosilicate Cement Based on Ternary By-Products." Civil Engineering Journal 7, no. 7 (July 1, 2021): 1264–74. http://dx.doi.org/10.28991/cej-2021-03091724.

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Portland cement is a popular binder but causes many adverse effects on the environment. That is due to the large consumption of raw materials and energy during production while emitting vast amounts of CO2. In recent years, Alkali Aluminosilicate Cement (AAC) has drawn much attention in research and development and promises to become a binder that can replace the traditional cement. In many studies of this binder, the content of the ingredients is often gradually changed to determine the optimal composition. The object of this paper is to optimize the composition of AAC using a combination of three by-products as the primary raw material, including Rush Husk Ash (RHA), Fly Ash (FA), and Ground Granulated Blast-Furnace Slag (GGBS). The investigation was conducted based on the critical parameter SiO2/Al2O3, and the D-optimal design. The FA and the GGBS were industrial product form, while the RHA was ground in a ball mill for 2 hours before mixing. The results show that this type of binder has setting time and soundness to meet standard cement requirements. While comparing to Portland cement, the AAC has a faster setting time, slower development of compressive strength in the early stages but a higher strength at the age of 56 days. According to the highest compressive strength at 28 days and high fly ash content, the optimal composition was RHA of 27.8%, FA of 41.8%, and GGBS of 15.4%, corresponding to the ratio SiO2/Al2O3 of 3.83. In addition, compressive strength at 28 days of the mortar specimens with the optimal binder and the ratio of water/ cement at 0.32 reached 63 MPa. Doi: 10.28991/cej-2021-03091724 Full Text: PDF
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Kruszewski, Francis H., Laura H. Hearn, Kyle T. Smith, Janice J. Teal, Virginia C. Gordon, and Michael S. Dickens. "Application of the EYTEX™ System to the Evaluation of Cosmetic Products and their Ingredients." Alternatives to Laboratory Animals 20, no. 1 (January 1992): 146–63. http://dx.doi.org/10.1177/026119299202000120.

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465 cosmetic product formulations and raw ingredients were evaluated with the EYTEX™ system to determine the potential of this in vitro alternative for identifying eye irritation potential. The EYTEX™ system is a non-animal, biochemical procedure developed by Ropak Laboratories, Irvine, CA, that was designed to approximate the Draize rabbit eye irritation assay for the evaluation of ocular irritation. Avon Products Inc. provided all the test samples, which included over 30 different product types and represented a wide range of eye irritancy. All the EYTEX™ protocols available at the time of this study were used. Samples were evaluated double-blind with both the membrane partition assay (MPA) and the rapid membrane assay (RMA). When appropriate, the standard assay (STD) and the alkaline membrane assay (AMA) were used, as well as specific, documented protocol modifications. EYTEX™ results were correlated with rabbit eye irritation data which was obtained from the historical records of Avon Products Inc. A positive agreement of EYTEX™ results with the in vivo assay was demonstrated by an overall concordance of 80%. The assay error was 20%, of which 18% was due to an overestimation of sample irritancy (false positives) and 2% was attributed to underestimation (false negatives). Overestimation error in this study was due in part to the inability of the protocols to accurately classify test samples with very low irritation potential. Underestimation of sample irritancy was generally associated with ethoxylated materials and high concentrations of specific types of surfactants. 100% sensitivity and 85% predictability were described by the data, indicating the efficiency of EYTEX™ in identifying known irritants. A specificity rate of 39% showed the EYTEX™ assay to be weak in discerning non-irritants. However, the EYTEX™ protocols used in this study were not designed to identify non-irritants. A compatibility rate of 99% proved the effectiveness of the EYTEX™ assay in accommodating a diversity of product types. The EYTEX™ system protocols, when used appropriately, can provide a conservative means of assessing the irritant potential of most cosmetic formulations and their ingredients.
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Stein, Robert, Andreas Makris, Iain Macpherson, Luke Hughes-Davies, Andrea Marshall, Georgina Dotchin, David A. Cameron, et al. "Abstract OT3-32-01: OPTIMA, a prospective randomized trial to validate the clinical utility and cost-effectiveness of gene expression test-directed chemotherapy decisions in high clinical risk early breast cancer." Cancer Research 83, no. 5_Supplement (March 1, 2023): OT3–32–01—OT3–32–01. http://dx.doi.org/10.1158/1538-7445.sabcs22-ot3-32-01.

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Abstract Background: Multi-parameter tumor gene expression assays (MPAs) are used to estimate individual patient risk and guide chemotherapy use in hormone-sensitive, HER2-negative early breast cancer. The TAILORx trial supports MPA use in a node-negative population. Evidence for MPA use in postmenopausal node-positive breast cancer has been provided by the RxPONDER trial interim analysis but this relies on the absence of superiority in an analysis where &gt;50% of events were unrelated to breast cancer. There is much uncertainty about MPA use for premenopausal patients. OPTIMA (Optimal Personalised Treatment of early breast cancer usIng Multi-parameter Analysis) (ISRCTN42400492) is a prospective international randomized controlled trial designed to validate MPAs as predictors of chemotherapy sensitivity in a largely node-positive breast cancer population. Methods: OPTIMA is a partially blinded study with an adaptive two-stage design. The trial recruits women and men age 40 or older with resected ER-positive, HER2-negative invasive breast cancer and up to 9 involved axillary lymph nodes. Randomization is to standard management (chemotherapy and endocrine therapy) or to MPA-directed treatment using the Prosigna (PAM50) test. Those with a Prosigna tumor Score (ROR_PT) &gt;60 receive standard management whilst those with a low score (≤60) tumor are treated with endocrine therapy alone. Endocrine therapy for pre-menopausal women includes ovarian suppression for all participants unless they experience a chemotherapy-induced menopause. Adjuvant abemaciclib is permitted. The trial will be analyzed for (1) non-inferiority of recurrence according to randomization and (2) cost-effectiveness. The key secondary outcome is non-inferiority of recurrence for patients with low ROR_PT score tumors. The efficacy analyses will be performed Per Protocol using Invasive Breast Cancer Free Survival (IBCFS) as the primary outcome measure to limit the risk of a false non-inferiority conclusion. Recruitment of 4500 patients over 8 years will permit demonstration of up to 3% non-inferiority of test-directed treatment with at least 83% power, assuming 5-year IBCFS is 87% with standard management. An integrated qualitative recruitment study addresses challenges to consent and recruitment, building on experience from the feasibility study which found that a multidisciplinary approach is important for recruitment success. OPTIMA is strongly supported by a patient group which has helped design all patient documents and which is represented on the TMG. Results: The OPTIMA main trial opened in January 2017 and has continued to recruit throughout the COVID-19 pandemic. Overall recruitment as of 1 July 2022 was 2814 (2593 from UK, 221 from Norway). Patient characteristics are well balanced between the trial arms. Currently 95% of randomized participants are eligible for inclusion in the PP analysis. 66% of the MPA-directed arm participants have been allocated to endocrine therapy only. The test failure rate is &lt; 1%. Conclusion: OPTIMA will provide robust unbiased evidence on test-directed chemotherapy safety for both postmenopausal and premenopausal women with 1-3 involved nodes as well as for patients with 4-9 involved nodes and for patients treated with abemaciclib. Funding: OPTIMA is funded by the UK NIHR HTA Programme (10/34/501) and in Norway by KLINBEFORSK and the Norwegian Cancer Society. Views expressed are those of the authors and not those of the HTA Programme, NIHR, NHS or the Department of Health. Trial Inquiries: OPTIMA@warwick.ac.uk Patient characteristics Citation Format: Robert Stein, Andreas Makris, Iain Macpherson, Luke Hughes-Davies, Andrea Marshall, Georgina Dotchin, David A. Cameron, Belinda E. Kiely, Caroline Wilson, Anne Armstrong, Helena M. Earl, Christopher J. Poole, Janice Tsang, Bjørn Naume, Daniel Rea, Hege Ohnstad, Peter S. Hall, Stuart A. McIntosh, Bethany Shinkins, Christopher McCabe, Adrienne Morgan, John MS Bartlett, Janet A. Dunn. OPTIMA, a prospective randomized trial to validate the clinical utility and cost-effectiveness of gene expression test-directed chemotherapy decisions in high clinical risk early breast cancer. [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr OT3-32-01.
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Pytlik, Andrzej. "Process Characteristics Of Hydraulic Legs Equipped With Safety Valves At Dynamic Load Caused By A Mining Tremor." Archives of Mining Sciences 60, no. 2 (June 1, 2015): 595–612. http://dx.doi.org/10.1515/amsc-2015-0039.

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Abstract The article presents process characteristics of hydraulic legs, a powered roof support and an individual roof support that are equipped with pressure relief valves and additional safety valves protecting the legs against dynamic loads caused by mining tremors. A two-telescopic hydraulic leg ϕ330 type was tested using dynamic pile testing, equipped with a valve bank with pressure relief valve and an additional safety valve. The tests included the following models of safety valves described in references (Gwiazda, 1997; Irresberger et al., 2008): – slide-piston with a roller spring, – seat-cone with gas spring, – slide-piston with a roller spring, – two-stage valve (a control valve and a main valve connected in one support). Using pressure charts in time function it is possible to determine how fast the amplitudes of pressure increase with the h height of a ram increase, thereby, Ek kinetic energy of ram’s stroke and p momentum impacting the leg equipped with the valve. Maximum pressure in the leg with the slide-piston valve raised to 64 MPa (with impact mass drop at h = 0.25 m) up to 129 MPa (h = 0.3 m) i.e. by 100%. Pressure increase to pmax = 158 MPa was noted during a test of the slide-piston leg equipped with the valve and with a drop of h = 0.5 m This poses a great hazard that can destroy the valve and therefore cause a loss of load-bearing capacity. Conducted research of SHC hydraulic legs of an individual roof support showed that (Pytlik & Pacześniowski, 2012; Pytlik & Rabsztyn, 2011) quick relief valves had higher efficiency than standard valves mounted in SHC legs, which resulted in lower pressure in the leg by 7 MPa. It has an essential importance for stability of leg’s cylinder and its sealing. The test of the leg with a valve battery was based on its dynamic load impacted by a ram (impact mass) of m1 = 4,000 kg relieved at the leg placed between a cross-bar of m2 = 3,300 kg and post’s foundation. Recording of p pressure of the fluid in its space under piston was made with sampling frequency of 9.6 kHz, Moreover, the research also included test of the same type of SHC leg with BZG-2FS battery (equipped with gas spring) using ram’s mass of m1 = 2,0000 kg and the cross-bass of m2 = 6,600 kg. The leg transferred the load, stroke type, of Ek = 29,5 kJ kinetic energy without any damages. A time-lapse analysis of photos showing the opening moment of the safety valve indicated that its opening had taken place 8 ms after the moment when the leg was impacted and indicated propagation of the hydraulic fluid stream’s front with maximum velocity of about 60 m/s, and maximum momentary intensity of fluid flowing through a bypass valve amounted to Qc max = 683 l/min. The tests of work characteristics of safety valves (Pytlik, 2013, 2014) included valves with M40×2 terminal thread of the following designs: – slide-piston – with three rows of fluid outlets, – slide-piston – with two rows of fluid outlets, – seat-cone – with a single row of fluid outlets. The tests of valves were conducted on the basis of capacity research methodology based on fluid increase of fluid stream caused by mass stroke impacting the leg equipped with the valve, up to twice the working pressure adjusted value of the valve. Such test simulates dynamic load of the hydraulic leg with the valve during mining tremors. Tests results of capacity and valve opening time may be used to determine yielding of an individual powered roof support and to optimize valve construction in order to improve capacity and working time. On the basis of carried out research concerning momentary intensity of Qc flow of safety valves with M40×2 terminal, it may be stated that the valves are characterised by a high level of capacity, presented on charts, and short working time – 3 up to 5 ms. The best technical parameters had a prototype seat-cone valve.
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Cesarini, Paul. "‘Opening’ the Xbox." M/C Journal 7, no. 3 (July 1, 2004). http://dx.doi.org/10.5204/mcj.2371.

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“As the old technologies become automatic and invisible, we find ourselves more concerned with fighting or embracing what’s new”—Dennis Baron, From Pencils to Pixels: The Stage of Literacy Technologies What constitutes a computer, as we have come to expect it? Are they necessarily monolithic “beige boxes”, connected to computer monitors, sitting on computer desks, located in computer rooms or computer labs? In order for a device to be considered a true computer, does it need to have a keyboard and mouse? If this were 1991 or earlier, our collective perception of what computers are and are not would largely be framed by this “beige box” model: computers are stationary, slab-like, and heavy, and their natural habitats must be in rooms specifically designated for that purpose. In 1992, when Apple introduced the first PowerBook, our perception began to change. Certainly there had been other portable computers prior to that, such as the Osborne 1, but these were more luggable than portable, weighing just slightly less than a typical sewing machine. The PowerBook and subsequent waves of laptops, personal digital assistants (PDAs), and so-called smart phones from numerous other companies have steadily forced us to rethink and redefine what a computer is and is not, how we interact with them, and the manner in which these tools might be used in the classroom. However, this reconceptualization of computers is far from over, and is in fact steadily evolving as new devices are introduced, adopted, and subsequently adapted for uses beyond of their original purpose. Pat Crowe’s Book Reader project, for example, has morphed Nintendo’s GameBoy and GameBoy Advance into a viable electronic book platform, complete with images, sound, and multi-language support. (Crowe, 2003) His goal was to take this existing technology previously framed only within the context of proprietary adolescent entertainment, and repurpose it for open, flexible uses typically associated with learning and literacy. Similar efforts are underway to repurpose Microsoft’s Xbox, perhaps the ultimate symbol of “closed” technology given Microsoft’s propensity for proprietary code, in order to make it a viable platform for Open Source Software (OSS). However, these efforts are not forgone conclusions, and are in fact typical of the ongoing battle over who controls the technology we own in our homes, and how open source solutions are often at odds with a largely proprietary world. In late 2001, Microsoft launched the Xbox with a multimillion dollar publicity drive featuring events, commercials, live models, and statements claiming this new console gaming platform would “change video games the way MTV changed music”. (Chan, 2001) The Xbox launched with the following technical specifications: 733mhz Pentium III 64mb RAM, 8 or 10gb internal hard disk drive CD/DVD ROM drive (speed unknown) Nvidia graphics processor, with HDTV support 4 USB 1.1 ports (adapter required), AC3 audio 10/100 ethernet port, Optional 56k modem (TechTV, 2001) While current computers dwarf these specifications in virtually all areas now, for 2001 these were roughly on par with many desktop systems. The retail price at the time was $299, but steadily dropped to nearly half that with additional price cuts anticipated. Based on these features, the preponderance of “off the shelf” parts and components used, and the relatively reasonable price, numerous programmers quickly became interested in seeing it if was possible to run Linux and additional OSS on the Xbox. In each case, the goal has been similar: exceed the original purpose of the Xbox, to determine if and how well it might be used for basic computing tasks. If these attempts prove to be successful, the Xbox could allow institutions to dramatically increase the student-to-computer ratio in select environments, or allow individuals who could not otherwise afford a computer to instead buy and Xbox, download and install Linux, and use this new device to write, create, and innovate . This drive to literally and metaphorically “open” the Xbox comes from many directions. Such efforts include Andrew Huang’s self-published “Hacking the Xbox” book in which, under the auspices of reverse engineering, Huang analyzes the architecture of the Xbox, detailing step-by-step instructions for flashing the ROM, upgrading the hard drive and/or RAM, and generally prepping the device for use as an information appliance. Additional initiatives include Lindows CEO Michael Robertson’s $200,000 prize to encourage Linux development on the Xbox, and the Xbox Linux Project at SourceForge. What is Linux? Linux is an alternative operating system initially developed in 1991 by Linus Benedict Torvalds. Linux was based off a derivative of the MINIX operating system, which in turn was a derivative of UNIX. (Hasan 2003) Linux is currently available for Intel-based systems that would normally run versions of Windows, PowerPC-based systems that would normally run Apple’s Mac OS, and a host of other handheld, cell phone, or so-called “embedded” systems. Linux distributions are based almost exclusively on open source software, graphic user interfaces, and middleware components. While there are commercial Linux distributions available, these mainly just package the freely available operating system with bundled technical support, manuals, some exclusive or proprietary commercial applications, and related services. Anyone can still download and install numerous Linux distributions at no cost, provided they do not need technical support beyond the community / enthusiast level. Typical Linux distributions come with open source web browsers, word processors and related productivity applications (such as those found in OpenOffice.org), and related tools for accessing email, organizing schedules and contacts, etc. Certain Linux distributions are more or less designed for network administrators, system engineers, and similar “power users” somewhat distanced from that of our students. However, several distributions including Lycoris, Mandrake, LindowsOS, and other are specifically tailored as regular, desktop operating systems, with regular, everyday computer users in mind. As Linux has no draconian “product activation key” method of authentication, or digital rights management-laden features associated with installation and implementation on typical desktop and laptop systems, Linux is becoming an ideal choice both individually and institutionally. It still faces an uphill battle in terms of achieving widespread acceptance as a desktop operating system. As Finnie points out in Desktop Linux Edges Into The Mainstream: “to attract users, you need ease of installation, ease of device configuration, and intuitive, full-featured desktop user controls. It’s all coming, but slowly. With each new version, desktop Linux comes closer to entering the mainstream. It’s anyone’s guess as to when critical mass will be reached, but you can feel the inevitability: There’s pent-up demand for something different.” (Finnie 2003) Linux is already spreading rapidly in numerous capacities, in numerous countries. Linux has “taken hold wherever computer users desire freedom, and wherever there is demand for inexpensive software.” Reports from technology research company IDG indicate that roughly a third of computers in Central and South America run Linux. Several countries, including Mexico, Brazil, and Argentina, have all but mandated that state-owned institutions adopt open source software whenever possible to “give their people the tools and education to compete with the rest of the world.” (Hills 2001) The Goal Less than a year after Microsoft introduced the The Xbox, the Xbox Linux project formed. The Xbox Linux Project has a goal of developing and distributing Linux for the Xbox gaming console, “so that it can be used for many tasks that Microsoft don’t want you to be able to do. ...as a desktop computer, for email and browsing the web from your TV, as a (web) server” (Xbox Linux Project 2002). Since the Linux operating system is open source, meaning it can freely be tinkered with and distributed, those who opt to download and install Linux on their Xbox can do so with relatively little overhead in terms of cost or time. Additionally, Linux itself looks very “windows-like”, making for fairly low learning curve. To help increase overall awareness of this project and assist in diffusing it, the Xbox Linux Project offers step-by-step installation instructions, with the end result being a system capable of using common peripherals such as a keyboard and mouse, scanner, printer, a “webcam and a DVD burner, connected to a VGA monitor; 100% compatible with a standard Linux PC, all PC (USB) hardware and PC software that works with Linux.” (Xbox Linux Project 2002) Such a system could have tremendous potential for technology literacy. Pairing an Xbox with Linux and OpenOffice.org, for example, would provide our students essentially the same capability any of them would expect from a regular desktop computer. They could send and receive email, communicate using instant messaging IRC, or newsgroup clients, and browse Internet sites just as they normally would. In fact, the overall browsing experience for Linux users is substantially better than that for most Windows users. Internet Explorer, the default browser on all systems running Windows-base operating systems, lacks basic features standard in virtually all competing browsers. Native blocking of “pop-up” advertisements is still not yet possible in Internet Explorer without the aid of a third-party utility. Tabbed browsing, which involves the ability to easily open and sort through multiple Web pages in the same window, often with a single mouse click, is also missing from Internet Explorer. The same can be said for a robust download manager, “find as you type”, and a variety of additional features. Mozilla, Netscape, Firefox, Konqueror, and essentially all other OSS browsers for Linux have these features. Of course, most of these browsers are also available for Windows, but Internet Explorer is still considered the standard browser for the platform. If the Xbox Linux Project becomes widely diffused, our students could edit and save Microsoft Word files in OpenOffice.org’s Writer program, and do the same with PowerPoint and Excel files in similar OpenOffice.org components. They could access instructor comments originally created in Microsoft Word documents, and in turn could add their own comments and send the documents back to their instructors. They could even perform many functions not yet capable in Microsoft Office, including saving files in PDF or Flash format without needing Adobe’s Acrobat product or Macromedia’s Flash Studio MX. Additionally, by way of this project, the Xbox can also serve as “a Linux server for HTTP/FTP/SMB/NFS, serving data such as MP3/MPEG4/DivX, or a router, or both; without a monitor or keyboard or mouse connected.” (Xbox Linux Project 2003) In a very real sense, our students could use these inexpensive systems previously framed only within the context of entertainment, for educational purposes typically associated with computer-mediated learning. Problems: Control and Access The existing rhetoric of technological control surrounding current and emerging technologies appears to be stifling many of these efforts before they can even be brought to the public. This rhetoric of control is largely typified by overly-restrictive digital rights management (DRM) schemes antithetical to education, and the Digital Millennium Copyright Act (DMCA). Combined,both are currently being used as technical and legal clubs against these efforts. Microsoft, for example, has taken a dim view of any efforts to adapt the Xbox to Linux. Microsoft CEO Steve Ballmer, who has repeatedly referred to Linux as a cancer and has equated OSS as being un-American, stated, “Given the way the economic model works - and that is a subsidy followed, essentially, by fees for every piece of software sold - our license framework has to do that.” (Becker 2003) Since the Xbox is based on a subsidy model, meaning that Microsoft actually sells the hardware at a loss and instead generates revenue off software sales, Ballmer launched a series of concerted legal attacks against the Xbox Linux Project and similar efforts. In 2002, Nintendo, Sony, and Microsoft simultaneously sued Lik Sang, Inc., a Hong Kong-based company that produces programmable cartridges and “mod chips” for the PlayStation II, Xbox, and Game Cube. Nintendo states that its company alone loses over $650 million each year due to piracy of their console gaming titles, which typically originate in China, Paraguay, and Mexico. (GameIndustry.biz) Currently, many attempts to “mod” the Xbox required the use of such chips. As Lik Sang is one of the only suppliers, initial efforts to adapt the Xbox to Linux slowed considerably. Despite that fact that such chips can still be ordered and shipped here by less conventional means, it does not change that fact that the chips themselves would be illegal in the U.S. due to the anticircumvention clause in the DMCA itself, which is designed specifically to protect any DRM-wrapped content, regardless of context. The Xbox Linux Project then attempted to get Microsoft to officially sanction their efforts. They were not only rebuffed, but Microsoft then opted to hire programmers specifically to create technological countermeasures for the Xbox, to defeat additional attempts at installing OSS on it. Undeterred, the Xbox Linux Project eventually arrived at a method of installing and booting Linux without the use of mod chips, and have taken a more defiant tone now with Microsoft regarding their circumvention efforts. (Lettice 2002) They state that “Microsoft does not want you to use the Xbox as a Linux computer, therefore it has some anti-Linux-protection built in, but it can be circumvented easily, so that an Xbox can be used as what it is: an IBM PC.” (Xbox Linux Project 2003) Problems: Learning Curves and Usability In spite of the difficulties imposed by the combined technological and legal attacks on this project, it has succeeded at infiltrating this closed system with OSS. It has done so beyond the mere prototype level, too, as evidenced by the Xbox Linux Project now having both complete, step-by-step instructions available for users to modify their own Xbox systems, and an alternate plan catering to those who have the interest in modifying their systems, but not the time or technical inclinations. Specifically, this option involves users mailing their Xbox systems to community volunteers within the Xbox Linux Project, and basically having these volunteers perform the necessary software preparation or actually do the full Linux installation for them, free of charge (presumably not including shipping). This particular aspect of the project, dubbed “Users Help Users”, appears to be fairly new. Yet, it already lists over sixty volunteers capable and willing to perform this service, since “Many users don’t have the possibility, expertise or hardware” to perform these modifications. Amazingly enough, in some cases these volunteers are barely out of junior high school. One such volunteer stipulates that those seeking his assistance keep in mind that he is “just 14” and that when performing these modifications he “...will not always be finished by the next day”. (Steil 2003) In addition to this interesting if somewhat unusual level of community-driven support, there are currently several Linux-based options available for the Xbox. The two that are perhaps the most developed are GentooX, which is based of the popular Gentoo Linux distribution, and Ed’s Debian, based off the Debian GNU / Linux distribution. Both Gentoo and Debian are “seasoned” distributions that have been available for some time now, though Daniel Robbins, Chief Architect of Gentoo, refers to the product as actually being a “metadistribution” of Linux, due to its high degree of adaptability and configurability. (Gentoo 2004) Specifically, the Robbins asserts that Gentoo is capable of being “customized for just about any application or need. ...an ideal secure server, development workstation, professional desktop, gaming system, embedded solution or something else—whatever you need it to be.” (Robbins 2004) He further states that the whole point of Gentoo is to provide a better, more usable Linux experience than that found in many other distributions. Robbins states that: “The goal of Gentoo is to design tools and systems that allow a user to do their work pleasantly and efficiently as possible, as they see fit. Our tools should be a joy to use, and should help the user to appreciate the richness of the Linux and free software community, and the flexibility of free software. ...Put another way, the Gentoo philosophy is to create better tools. When a tool is doing its job perfectly, you might not even be very aware of its presence, because it does not interfere and make its presence known, nor does it force you to interact with it when you don’t want it to. The tool serves the user rather than the user serving the tool.” (Robbins 2004) There is also a so-called “live CD” Linux distribution suitable for the Xbox, called dyne:bolic, and an in-progress release of Slackware Linux, as well. According to the Xbox Linux Project, the only difference between the standard releases of these distributions and their Xbox counterparts is that “...the install process – and naturally the bootloader, the kernel and the kernel modules – are all customized for the Xbox.” (Xbox Linux Project, 2003) Of course, even if Gentoo is as user-friendly as Robbins purports, even if the Linux kernel itself has become significantly more robust and efficient, and even if Microsoft again drops the retail price of the Xbox, is this really a feasible solution in the classroom? Does the Xbox Linux Project have an army of 14 year olds willing to modify dozens, perhaps hundreds of these systems for use in secondary schools and higher education? Of course not. If such an institutional rollout were to be undertaken, it would require significant support from not only faculty, but Department Chairs, Deans, IT staff, and quite possible Chief Information Officers. Disk images would need to be customized for each institution to reflect their respective needs, ranging from setting specific home pages on web browsers, to bookmarks, to custom back-up and / or disk re-imaging scripts, to network authentication. This would be no small task. Yet, the steps mentioned above are essentially no different than what would be required of any IT staff when creating a new disk image for a computer lab, be it one for a Windows-based system or a Mac OS X-based one. The primary difference would be Linux itself—nothing more, nothing less. The institutional difficulties in undertaking such an effort would likely be encountered prior to even purchasing a single Xbox, in that they would involve the same difficulties associated with any new hardware or software initiative: staffing, budget, and support. If the institutional in question is either unwilling or unable to address these three factors, it would not matter if the Xbox itself was as free as Linux. An Open Future, or a Closed one? It is unclear how far the Xbox Linux Project will be allowed to go in their efforts to invade an essentially a proprietary system with OSS. Unlike Sony, which has made deliberate steps to commercialize similar efforts for their PlayStation 2 console, Microsoft appears resolute in fighting OSS on the Xbox by any means necessary. They will continue to crack down on any companies selling so-called mod chips, and will continue to employ technological protections to keep the Xbox “closed”. Despite clear evidence to the contrary, in all likelihood Microsoft continue to equate any OSS efforts directed at the Xbox with piracy-related motivations. Additionally, Microsoft’s successor to the Xbox would likely include additional anticircumvention technologies incorporated into it that could set the Xbox Linux Project back by months, years, or could stop it cold. Of course, it is difficult to say with any degree of certainty how this “Xbox 2” (perhaps a more appropriate name might be “Nextbox”) will impact this project. Regardless of how this device evolves, there can be little doubt of the value of Linux, OpenOffice.org, and other OSS to teaching and learning with technology. This value exists not only in terms of price, but in increased freedom from policies and technologies of control. New Linux distributions from Gentoo, Mandrake, Lycoris, Lindows, and other companies are just now starting to focus their efforts on Linux as user-friendly, easy to use desktop operating systems, rather than just server or “techno-geek” environments suitable for advanced programmers and computer operators. While metaphorically opening the Xbox may not be for everyone, and may not be a suitable computing solution for all, I believe we as educators must promote and encourage such efforts whenever possible. I suggest this because I believe we need to exercise our professional influence and ultimately shape the future of technology literacy, either individually as faculty and collectively as departments, colleges, or institutions. Moran and Fitzsimmons-Hunter argue this very point in Writing Teachers, Schools, Access, and Change. One of their fundamental provisions they use to define “access” asserts that there must be a willingness for teachers and students to “fight for the technologies that they need to pursue their goals for their own teaching and learning.” (Taylor / Ward 160) Regardless of whether or not this debate is grounded in the “beige boxes” of the past, or the Xboxes of the present, much is at stake. Private corporations should not be in a position to control the manner in which we use legally-purchased technologies, regardless of whether or not these technologies are then repurposed for literacy uses. I believe the exigency associated with this control, and the ongoing evolution of what is and is not a computer, dictates that we assert ourselves more actively into this discussion. We must take steps to provide our students with the best possible computer-mediated learning experience, however seemingly unorthodox the technological means might be, so that they may think critically, communicate effectively, and participate actively in society and in their future careers. About the Author Paul Cesarini is an Assistant Professor in the Department of Visual Communication & Technology Education, Bowling Green State University, Ohio Email: pcesari@bgnet.bgsu.edu Works Cited http://xbox-linux.sourceforge.net/docs/debian.php>.Baron, Denis. “From Pencils to Pixels: The Stages of Literacy Technologies.” Passions Pedagogies and 21st Century Technologies. Hawisher, Gail E., and Cynthia L. Selfe, Eds. Utah: Utah State University Press, 1999. 15 – 33. Becker, David. “Ballmer: Mod Chips Threaten Xbox”. News.com. 21 Oct 2002. http://news.com.com/2100-1040-962797.php>. http://news.com.com/2100-1040-978957.html?tag=nl>. http://archive.infoworld.com/articles/hn/xml/02/08/13/020813hnchina.xml>. http://www.neoseeker.com/news/story/1062/>. http://www.bookreader.co.uk>.Finni, Scott. “Desktop Linux Edges Into The Mainstream”. TechWeb. 8 Apr 2003. http://www.techweb.com/tech/software/20030408_software. http://www.theregister.co.uk/content/archive/29439.html http://gentoox.shallax.com/. http://ragib.hypermart.net/linux/. http://www.itworld.com/Comp/2362/LWD010424latinlinux/pfindex.html. http://www.xbox-linux.sourceforge.net. http://www.theregister.co.uk/content/archive/27487.html. http://www.theregister.co.uk/content/archive/26078.html. http://www.us.playstation.com/peripherals.aspx?id=SCPH-97047. http://www.techtv.com/extendedplay/reviews/story/0,24330,3356862,00.html. http://www.wired.com/news/business/0,1367,61984,00.html. http://www.gentoo.org/main/en/about.xml http://www.gentoo.org/main/en/philosophy.xml http://techupdate.zdnet.com/techupdate/stories/main/0,14179,2869075,00.html. http://xbox-linux.sourceforge.net/docs/usershelpusers.html http://www.cnn.com/2002/TECH/fun.games/12/16/gamers.liksang/. Citation reference for this article MLA Style Cesarini, Paul. "“Opening” the Xbox" M/C: A Journal of Media and Culture <http://www.media-culture.org.au/0406/08_Cesarini.php>. APA Style Cesarini, P. (2004, Jul1). “Opening” the Xbox. M/C: A Journal of Media and Culture, 7, <http://www.media-culture.org.au/0406/08_Cesarini.php>
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Dissertations / Theses on the topic "Standard MPI-2 RMA"

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Mba, Mathieu Leonel. "Génération automatique de plate-forme matérielles distribuées pour des applications de traitement du signal." Electronic Thesis or Diss., Sorbonne université, 2023. http://www.theses.fr/2023SORUS341.

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Les langues locales ou langues maternelles propres aux individus jouent un rôle important pour leur épanouissement dans leurs différentes activités socio-économiques. Les langues africaines, et spécifiquement les langues camerounaises sont exposées à la disparition au profit des langues étrangères adoptées comme langues officielles au lendemain des indépendances. C’est la raison pour laquelle il est primordial de les numériser et les intégrer dans la majorité des services dématérialisés pour leur pérennisation. La reconnaissance vocale, largement utilisée comme interface d'interaction homme machine, peut être non seulement un outil d'intégration des langues locales dans les applications, mais aussi un outil de collecte et de numérisation des corpus. Les systèmes embarqués sont l'environnement par excellence de déploiement des applications qui exploitent cette interface d'interaction homme machine. Cela implique qu'il est nécessaire de prendre des mesures (à travers la réduction du temps de réponse) pour satisfaire la contrainte de temps réel très souvent rencontrée dans ce type d'application. Deux approches existent pour la réduction du temps de réponse des applications à savoir la parallélisation et l'usage des architectures matérielles efficaces. Dans cette thèse, nous exploitons une approche hybride pour réduire le temps de réponse d'une application. Nous le faisons par la parallélisation de cette application et sa mise en œuvre sur architecture reconfigurable. Une architecture dont les langages de mise en œuvre sont connus pour être de bas niveau. De plus, au vu de la multitude des problématiques posées par la mise en œuvre des systèmes parallèles sur architecture reconfigurable, il se pose un problème de productivité de l'ingénieur. Dans cette thèse, en vue de mettre en œuvre un système de reconnaissance vocale temps réel sur système embarqué, nous proposons, une approche de mise en œuvre productive d'applications parallèles sur architecture reconfigurable. Notre approche exploite MATIP un outil de conception orienté plateforme, comme FPGA Overlay basé sur la synthèse de haut niveau. Nous exploitons cette approche pour mettre en œuvre un modèle parallèle d'un algorithme d'extraction des caractéristiques pour la reconnaissance des langues à tons (caractéristique de la majorité des langues camerounaises). L'expérimentation de cette solution sur des mots isolés de la langue Kóló, en comparaison à d'autres propositions (version logicielle et IP matérielles), montre que, notre approche est non seulement productive en temps de mise en œuvre, mais aussi l'application parallèle obtenue est efficace en temps de traitement. C’est la raison pour laquelle nous avons mis en œuvre XMATIP une extension de MATIP pour rendre cette approche compatible à la co-conception et co-synthèse matérielle logicielle
Local languages or mother tongues of individuals play an essential role in their fulfillment in their various socio-economic activities. African languages and specifically Cameroonian languages are exposed to disappearance in favor of foreign languages adopted as official languages after independence. This is why it is essential to digitalize and integrate them into the majority of dematerialized services for their sustainability. Speech recognition, widely used as a human-machine interface, can be not only a tool for integrating local languages into applications but also a tool for collecting and digitizing corpora. Embedded systems are the preferred environment for deploying applications that use this human-machine interface. This implies that it is necessary to take measures (through the reduction of the reaction time) to satisfy the real-time constraint very often met in this type of application. Two approaches exist for the reduction of the application's response time, namely parallelization and the use of efficient hardware architectures. In this thesis, we exploit a hybrid approach to reduce the response time of an application. We do this by parallelizing this application and implementing it on a reconfigurable architecture. An architecture whose implementation languages are known to be low-level. Moreover, given the multitude of problems posed by the implementation of parallel systems on reconfigurable architecture, there is a problem with design productivity for the engineer. In this thesis, to implement a real-time speech recognition system on an embedded system, we propose an approach for the productive implementation of parallel applications on reconfigurable architecture. Our approach exploits MATIP, a platform-based design tool, as an FPGA Overlay based on high-level synthesis. We exploit this approach to implement a parallel model of a feature extraction algorithm for the recognition of tonal languages (characteristic of the majority of Cameroonian languages). The experimentation of this implementation on isolated words of the Kóló language, in comparison to other implementations (software version and hardware IP), shows that our approach is not only productive in implementation time but also the obtained parallel application is efficient in processing time. This is the reason why we implemented XMATIP an extension of MATIP to make this approach compatible with hardware-software co-design and co-synthesis
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Conference papers on the topic "Standard MPI-2 RMA"

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Peelukhana, Srikara Viswanath, Kranthi K. Kolli, Hanan Kerr, Mohamed Effat, Imran Arif, Mariano Fernandez-Ulloa, and Rupak K. Banerjee. "Improved Assessment of Coronary Flow Impairment Using N-13 Ammonia Positron Emission Tomography." In ASME 2013 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/sbc2013-14351.

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Non-invasive diagnosis of coronary artery disease (CAD) is achieved using rest and stress myocardial perfusion imaging (MPI) techniques. Currently, the MPI technique that is a standard of care is the Single Photon Emission Computed Tomography (SPECT). However, comparatively accurate and reliable MPI diagnostic test known as Positron Emission Tomography (PET) is also available and gaining increasing popularity. In this study, a comparison is made between the impairments and left ventricular (LV) ejection fraction (EF) reported by SPECT and PET. In addition, using PET data, flow defects were quantified using coronary flow reserve (CFR: ratio of flow at stress to the rest) in four coronary territories, left ventricle (LV), left circumflex (LCX), right coronary artery (RCA) and left anterior descending (LAD). Three patients with previous SPECT and suspected CAD were consented and further assessed with a PET cardiac N-13 ammonia scan according to the study protocol. The comparisons of the two imaging modalities showed discordance for patients 1 and 2 while they concurred for the patient 3. More importantly, quantification of the extent of defect showed an abnormal CFR value (< 2) of 1.67 (LCX) and 1.57 (RCA) for the patient 1 and 1.67 (LAD) and 1.75 (RCA) for patient 2. For the third patient, CFR value was abnormal at 0.85 for the RCA. Therefore, in contrast to SPECT, quantification of flow impairment using PET MPI in individual coronary territories will aid in better diagnosis of CAD.
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