compression data
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2022 ◽  
Vol 2022 ◽  
pp. 1-15
Author(s):  
Sávio Melo ◽  
Felipe Oliveira ◽  
Cícero Silva ◽  
Paulo Lopes ◽  
Gibeon Aquino

IoT devices deployed in Smart Cities usually have significant resource limitations. For this reason, offload tasks or data to other layers such as fog or cloud is regularly adopted to smooth out this issue. Although data offloading is a well-known aspect of fog computing, the specification of offloading policies is still an open issue due to the lack of clear guidelines. Therefore, we propose OffFog—an approach to guide the definition of data offloading policies in the context of fog computing. In order to evaluate OffFog, we extended the well-known simulator iFogSim and conducted an experimental study based on an urban surveillance system. The results demonstrated the benefits of implementing data offloading based on OffFog recommended policies. Furthermore, we identified the best configuration involving design decisions such as data compression, data criticality, and storage thresholds. The best configuration produced at least 76% improvement in network latency and 5% in the average execution time compared to the iFogSim default strategy. We believe these results represent a significant step towards establishing a systematic decision framework for data offloading policies in the context of fog computing.


Minerals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 608
Author(s):  
Pei-Lun Lee ◽  
Eugene Huang ◽  
Jennifer Kung

In situ high-pressure synchrotron X-ray diffraction and Raman spectroscopic experiments of scottyite, BaCu2Si2O7, were carried out in a diamond anvil cell up to 21 GPa at room temperature. X-ray diffraction patterns reveal four new peaks near 3.5, 3.1, 2.6 and 2.2 Å above 8 GPa, while some peaks of the original phase disappear above 10 GPa. In the Raman experiment, we observed two discontinuities in dν/dP, the slopes of Raman wavenumber (ν) of some vibration modes versus pressure (P), at approximately 8 and 12 GPa, indicating that the Si-O symmetrical and asymmetrical vibration modes change with pressure. Fitting the compression data to Birch–Murnaghan equation yields a bulk modulus of 102 ± 5 GPa for scottyite, assuming Ko′ is four. Scottyite shows anisotropic compressibility along three crystallographic axes, among which c-axis was the most compressible axis, b-axis was the last and a-axis was similar to the c-axis on the compression. Both X-ray and Raman spectroscopic data provide evidences that scottyite undergoes a reversible phase transformation at 8 GPa.


2020 ◽  
Vol 2 (2) ◽  
pp. 109-114
Author(s):  
Nadia Fariza Rizky ◽  
Surya Darma Nasution ◽  
Fadlina Fadlina

File size or large files are not only a problem in terms of storage, but also another problem when communication between computers. Data usage with a larger size will take longer transfer times compared to data that has a smaller size. Therefore to overcome this problem you can use data compression. Seeing the compression of data compression, data compression is needed that can reduce the size of the data, so that it gains the advantage of reducing the use of external storage media space, accelerating the process of transferring data between storage media, data utilization used in this study is the elias delta codes algorithm. Compression is a method used to reduce the bit or data from the original result to a new result. Where this compression will be applied into the algorithm, the elias delta codes algorithm. After getting the results of the compression it will be designed into Microsoft Visual Studio 2008


2020 ◽  
Author(s):  
Sahar. Mokhtari ◽  
Anthony.W. Wren

AbstractThis study addresses issues with currently used bone adhesives, by producing novel glass based skeletal adhesives through modification of the base glass composition to include copper (Cu) and by characterizing each glass with respect to structural changes. Bioactive glasses have found applications in fields such as orthopedics and dentistry, where they have been utilized for the restoration of bone and teeth. The present work outlines the formation of flexible organic-inorganic polyacrylic acid (PAA) – glass hybrids, commercial forms are known as glass ionomer cements (GICs). Initial stages of this research will involve characterization of the Cu-glasses, significant to evaluate the properties of the resulting adhesives. Scanning electron microscopy (SEM) of annealed Cu glasses indicates the presence of partial crystallization in the glass. The structural analysis of the glass using Raman suggests the formation of CuO nanocrystals on the surface. X-ray diffraction (XRD) pattern and X-ray photoelectron spectroscopy (XPS) further confirmed the formation of crystalline CuO phases on the surface of the annealed Cu-glass. The setting reaction was studied using Fourier transform infrared spectroscopy (ATR-FTIR). The mechanical properties of the Cu containing adhesives exhibited gel viscoelastic behavior and enhanced mechanical properties when compared to the control composition. Compression data indicated the Cu glass adhesives were efficient at energy dissipation due to the reversible interactions between CuO nano particles and PAA polymer chains.


2020 ◽  
pp. 102490792095886
Author(s):  
Kadir Küçükceran ◽  
Mustafa Kürşat Ayrancı ◽  
Zerrin Defne Dündar

Background: CPR model of a resuscitation to be ventilated with a bag valve mask constitutes a discussion when evaluated with the current guidance. Objective: This study aims to compare the synchronous (30–2) ventilation–compression method with asynchronous 110/min compression–10/min ventilation in cardiac arrests where an advanced airway management is not applied and where ventilation is provided by a bag valve mask on a mannequin. Methods: This simulation trial was performed using two clinical cardiopulmonary resuscitation scenarios: an asynchronous scenario with 10 ventilations per minute asynchronously when compression is applied as 110 compression per minute and a synchronous scenario in which 30 compressions:2 ventilations were performed synchronously. A total of 100 people in 50 groups applied these two scenarios on mannequin. Ventilation and compression data of both scenarios were recorded. Results: Evaluating the compression criteria in both the scenarios performed by 50 groups in total, in terms of all criteria except compression fraction, there was no statistically difference between the two scenarios (p > 0.05). Compression fraction values in the asynchronous scenario were found to be statistically significantly higher than the synchronous scenario (96.02 ± 2.35, 81.34 ± 4.42, p < 0.001). Evaluating the ventilation criteria in both the scenarios performed by 50 groups in total; there was a statistically significant difference in all criteria. Mean ventilation rate of the asynchronous scenario was statistically higher than the synchronous scenario (7.22 ± 2.42, 5.08 ± 0.75, p < 0.001). Mean ventilation volume of the synchronous scenario was statistically higher than the asynchronous scenario (353.24 ± 45.46, 527.40 ± 96.60, p < 0.001). Ventilation ratio in sufficient volume of the synchronous scenario was statistically higher than the asynchronous scenario (36.84 ± 14.47, 75.00 ± 21.24, p < 0.001). Ventilation ratio below the minimum volume limit of the asynchronous scenario was statistically higher than the synchronous scenario (62.48 ± 14.72, 17.86 ± 19.50, p < 0.001). Conclusion: In our study, we concluded that the cardiopulmonary resuscitation applied by the synchronous method reached better ventilation volumes. Evaluating together with any interruption in compression, comprehensive studies are needed to reveal which patients would benefit from this result.


2020 ◽  
Vol 105 (9) ◽  
pp. 1365-1374
Author(s):  
Mingda Lv ◽  
Jiachao Liu ◽  
Eran Greenberg ◽  
Vitali B. Prakapenka ◽  
Susannah M. Dorfman

Abstract Calcium carbonate (CaCO3) is one of the most abundant carbonates on Earth's surface and transports carbon to Earth's interior via subduction. Although some petrological observations support the preservation of CaCO3 in cold slabs to lower mantle depths, the geophysical properties and stability of CaCO3 at these depths are not known, due in part to complicated polymorphic phase transitions and lack of constraints on thermodynamic properties. Here we measured thermal equation of state of CaCO3-Pmmn, the stable polymorph of CaCO3 through much of the lower mantle, using synchrotron X-ray diffraction in a laser-heated diamond-anvil cell up to 75 GPa and 2200 K. The room-temperature compression data for CaCO3-Pmmn are fit with third-order Birch-Murnaghan equation of state, yielding KT0 = 146.7 (±1.9) GPa and K′0 = 3.4(±0.1) with V0 fixed to the value determined by ab initio calculation, 97.76 Å3. High-temperature compression data are consistent with zero-pressure thermal expansion αT = a0 + a1T with a0 = 4.3(±0.3)×10-5 K-1, a1 = 0.8(±0.2)×10-8 K-2, temperature derivative of the bulk modulus (∂KT/∂T)P = –0.021(±0.001) GPa/K; the Grüneisen parameter γ0 = 1.94(±0.02), and the volume independent constant q = 1.9(±0.3) at a fixed Debye temperature θ0 = 631 K predicted via ab initio calculation. Using these newly determined thermodynamic parameters, the density and bulk sound velocity of CaCO3-Pmmn and (Ca,Mg)-carbonate-bearing eclogite are quantitatively modeled from 30 to 80 GPa along a cold slab geotherm. With the assumption that carbonates are homogeneously mixed into the slab, the results indicate the presence of carbonates in the subducted slab is unlikely to be detected by seismic observations, and the buoyancy provided by carbonates has a negligible effect on slab dynamics.


Author(s):  
Larry Seiler ◽  
Daqi Lin ◽  
Cem Yuksel

We propose a method to reduce the footprint of compressed data by using modified virtual address translation to permit random access to the data. This extends our prior work on using page translation to perform automatic decompression and deswizzling upon accesses to fixed rate lossy or lossless compressed data. Our compaction method allows a virtual address space the size of the uncompressed data to be used to efficiently access variable-size blocks of compressed data. Compression and decompression take place between the first and second level caches, which allows fast access to uncompressed data in the first level cache and provides data compaction at all other levels of the memory hierarchy. This improves performance and reduces power relative to compressed but uncompacted data. An important property of our method is that compression, decompression, and reallocation are automatically managed by the new hardware without operating system intervention and without storing compression data in the page tables. As a result, although some changes are required in the page manager, it does not need to know the specific compression algorithm and can use a single memory allocation unit size. We tested our method with two sample CPU algorithms. When performing depth buffer occlusion tests, our method reduces the memory footprint by 3.1x. When rendering into textures, our method reduces the footprint by 1.69x before rendering and 1.63x after. In both cases, the power and cycle time are better than for uncompacted compressed data, and significantly better than for accessing uncompressed data.


Cartilage ◽  
2020 ◽  
pp. 194760352092858
Author(s):  
Adele Changoor ◽  
Martin Garon ◽  
Eric Quenneville ◽  
Shelley B. Bull ◽  
Karen Gordon ◽  
...  

Objective We aimed to demonstrate that electroarthrography (EAG) measures streaming potentials originating in the cartilage extracellular matrix during load bearing through electrodes adhered to skin surrounding an articular joint. Design Equine metacarpophalangeal joints were subjected to simulated physiological loads while (1) replacing synovial fluid with immersion buffers of different electrolyte concentrations and (2) directly degrading cartilage with trypsin. Results An inverse relationship between ionic strength and EAG coefficient was detected. Compared to native synovial fluid, EAG coefficients increased ( P < 0.05) for 5 of 6 electrodes immersed in 0.1X phosphate-buffered saline (PBS) (0.014 M NaCl), decreased ( P < 0.05) for 4 of 6 electrodes in 1X PBS (0.14 M NaCl), and decreased ( P < 0.05) for all 6 electrodes in 10X PBS (1.4 M NaCl). This relationship corresponds to similar studies where streaming potentials were directly measured on cartilage. EAG coefficients, obtained after trypsin degradation, were reduced ( P < 0.05) in 6 of 8, and 7 of 8 electrodes, during simulated standing and walking, respectively. Trypsin degradation was confirmed by direct cartilage assessments. Streaming potentials, measured by directly contacting cartilage, indicated lower cartilage stiffness ( P < 10−5). Unconfined compression data revealed reduced Em, representing proteoglycan matrix stiffness ( P = 0.005), no change in Ef, representing collagen network stiffness ( P = 0.15), and no change in permeability ( P = 0.24). Trypsin depleted proteoglycan as observed by both dimethylmethylene blue assay ( P = 0.0005) and safranin-O stained histological sections. Conclusion These data show that non-invasive EAG detects streaming potentials produced by cartilage during joint compression and has potential to become a diagnostic tool capable of detecting early cartilage degeneration.


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