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1.
Adam Prout Joanne M. Atlee Nancy A. Day Pourya Shaker 《Software and Systems Modeling》2012,11(2):251-272
We are investigating semantically configurable model-driven engineering (MDE). The goal of this work is a modelling environment that supports flexible, configurable modelling
notations, in which specifiers can configure the semantics of notations to suit their needs and yet still have access to the
types of analysis tools and code generators normally associated with MDE. In this paper, we describe semantically configurable code generation for a family of behavioural modelling notations. The family includes variants of statecharts, process algebras, Petri Nets,
and SDL88. The semantics of this family is defined using template semantics, which is a parameterized structured operational semantics in which parameters represent semantic variation points. A specific notation is derived
by instantiating the family’s template semantics with parameter values that specify semantic choices. We have developed a
code-generator generator (CGG) that creates a suitable Java code generator for a subset of derivable modelling notations.
Our prototype CGG supports 26 semantics parameters, 89 parameter values, and 7 composition operators. As a result, we are
able to produce code generators for a sizable family of modelling notations, though at present the performance of our generated
code is about an order of magnitude slower than that produced by commercial-grade generators. 相似文献
2.
Pourya Sarvari Pouya Sarvari Ivonne Ramírez-Díaz Frouzandeh Mahjoubi Karla Rubio 《International journal of molecular sciences》2022,23(17)
Epigenetic modifications are known to regulate cell phenotype during cancer progression, including breast cancer. Unlike genetic alterations, changes in the epigenome are reversible, thus potentially reversed by epi-drugs. Breast cancer, the most common cause of cancer death worldwide in women, encompasses multiple histopathological and molecular subtypes. Several lines of evidence demonstrated distortion of the epigenetic landscape in breast cancer. Interestingly, mammary cells isolated from breast cancer patients and cultured ex vivo maintained the tumorigenic phenotype and exhibited aberrant epigenetic modifications. Recent studies indicated that the therapeutic efficiency for breast cancer regimens has increased over time, resulting in reduced mortality. Future medical treatment for breast cancer patients, however, will likely depend upon a better understanding of epigenetic modifications. The present review aims to outline different epigenetic mechanisms including DNA methylation, histone modifications, and ncRNAs with their impact on breast cancer, as well as to discuss studies highlighting the central role of epigenetic mechanisms in breast cancer pathogenesis. We propose new research areas that may facilitate locus-specific epigenome editing as breast cancer therapeutics. 相似文献
3.
Study of morphology and gas separation properties of polysulfone/titanium dioxide mixed matrix membranes 下载免费PDF全文
Pourya Moradihamedani Nor Azowa Ibrahim Wan Md Zin Wan Yunus Nor Azah Yusof 《Polymer Engineering and Science》2015,55(2):367-374
Polysulfone (PSf)‐based mixed matrix membranes (MMMs) with the incorporation of titanium dioxide (TiO2) nanoparticles were prepared. Distribution and agglomeration of TiO2 in polymer matrix and also surface of membranes were observed by scanning electron microscopy, transmission electron microscopy, and energy dispersive X‐ray. Variation in surface roughness of MMMs with different TiO2 loadings was analyzed by atomic force microscopy. Physical properties of membranes before and after cross‐linking were identified through thermal gravimetric analysis. At low TiO2 loadings (≤3 wt%), both CO2 and CH4 permeabilities decreased and consequently gas selectivity improved and reached to 36.5 at 3 bar pressure. Interestingly, PSf/TiO2 3 wt% membrane did not allow to CH4 molecules to pass through the membrane and this sample just had CO2 permeability at 1 bar pressure. Gas permeability increased considerably at high filler contents (≥5 wt%) and CO2 permeance reached to 37.7 GPU for PSf/TiO2 7 wt% at 7 bar pressure. It was detected that, critical nanoparticle aggregation has occurred at higher filler loadings (≥5 wt%), which contributed to formation of macrovoids and defects in MMMs. Accordingly, MMMs with higher gas permeance and lower gas selectivity were prepared in higher TiO2 contents (≥5 wt%). POLYM. ENG. SCI., 55:367–374, 2015. © 2014 Society of Plastics Engineers 相似文献
4.
N. Movahedi S. M. H. Mirbagheri S. R. Hoseini 《Metals and Materials International》2014,20(4):757-763
In this study an attempt was carried out to determine the effect of production temperature on the mechanical properties and energy absorption behavior of closed-cell A356 alloy foams under uniaxial compression test. For this purpose, three different A356 alloy closed-cell foams were synthesized at three different casting temperatures, 650 °C, 675 °C and 700 °C by adding the same amounts of granulated calcium as thickening and TiH2 as blowing agent. The samples were characterized by SEM to study the pore morphology at different foaming temperatures. Compression tests of the A356 foams were carried out to assess their mechanical properties and energy absorption behavior. The results indicated that increasing the foaming temperature from 650 °C to 675 °C and 700 °C reduces the relative density of closed cell A356 alloys by 18.3% and 38% respectively and consequently affects the compressive strength and energy absorption of cellular structures by changing them from equiaxed polyhedral closed cells to distorted cells. Also at 700 °C foaming temperature, growth of micro-pores and coalescence with other surrounding pores leads to several big voids. 相似文献
5.
Karuppaiah Geetha Veerasamy Anitha Mohamed Elhoseny Shankar Kathiresan Pourya Shamsolmoali Mahmoud M. Selim 《Expert Systems》2021,38(1)
Recently, medical image compression becomes essential to effectively handle large amounts of medical data for storage and communication purposes. Vector quantization (VQ) is a popular image compression technique, and the commonly used VQ model is Linde–Buzo–Gray (LBG) that constructs a local optimal codebook to compress images. The codebook construction was considered as an optimization problem, and a bioinspired algorithm was employed to solve it. This article proposed a VQ codebook construction approach called the L2‐LBG method utilizing the Lion optimization algorithm (LOA) and Lempel Ziv Markov chain Algorithm (LZMA). Once LOA constructed the codebook, LZMA was applied to compress the index table and further increase the compression performance of the LOA. A set of experimentation has been carried out using the benchmark medical images, and a comparative analysis was conducted with Cuckoo Search‐based LBG (CS‐LBG), Firefly‐based LBG (FF‐LBG) and JPEG2000. The compression efficiency of the presented model was validated in terms of compression ratio (CR), compression factor (CF), bit rate, and peak signal to noise ratio (PSNR). The proposed L2‐LBG method obtained a higher CR of 0.3425375 and PSNR value of 52.62459 compared to CS‐LBG, FA‐LBG, and JPEG2000 methods. The experimental values revealed that the L2‐LBG process yielded effective compression performance with a better‐quality reconstructed image. 相似文献
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7.
S. A. Hoseini M. R. Hantehzadeh P. Salavati Dezfooli Sadjad Salavati Dezfooli S. Najmodein Hoseini 《Journal of Fusion Energy》2013,32(4):488-495
TiO2 films have been deposited on BK7 substrates by DC cylindrical magnetron sputtering setup in ambient temperature. The samples were fabricated at various O2/Ar reactive gas mixtures. The effects of changing O2 amount in O2/Ar reactive gas mixture on structural, morphological and optical properties of films were studied. The thickness of films was measured by surface profile meter. Thickness of films decreases with increasing the O2 amount in gas mixture. XRD studies shows that the films are amorphous. Atomic Force Microscopy was used to evaluate and compare the surface roughness and morphologies. The optical properties (transmission and reflection) of the samples were measured by UV–Vis–NIR spectrophotometer. Results show that increasing the O2 amount in O2/Ar mixture changes the surface morphologies and optical properties of films. All films exhibit a transmittance higher than 65 % in the visible region. The band gap of films was calculated from the optical measurements. The band gap of TiO2 thin films increases from 3.471 to 3.526 for different O2/Ar amounts. 相似文献
8.
S. M. Hoseini M. Farrokhi A. J. Koshkouei 《International Journal of Adaptive Control and Signal Processing》2010,24(1):65-82
This paper presents an adaptive output feedback stabilization method based on neural networks (NNs) for nonlinear non‐minimum phase systems. The proposed controller comprises a linear, a neuro‐adaptive, and an adaptive robustifying parts. The NN is designed to approximate the matched uncertainties of the system. The inputs of the NN are the tapped delays of the system input–output signals. In addition, an appropriate reference signal is proposed to compensate the unmatched uncertainties inherent in the internal system dynamics. The adaptation laws for the NN weights and adaptive gains are obtained using Lyapunov's direct method. These adaptation laws employ a linear observer of system dynamics that is realizable. The ultimate boundedness of the error signals are analytically shown using Lyapunov's method. The effectiveness of the proposed scheme is shown by applying to a translation oscillator rotational actuator model. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
9.
Ali Reza GHANIZADEH Hakime ABBASLOU Amir Tavana AMLASHI Pourya ALIDOUST 《Frontiers of Structural and Civil Engineering》2019,13(1):215
Plastic concrete is an engineering material, which is commonly used for construction of cut-off walls to prevent water seepage under the dam. This paper aims to explore two machine learning algorithms including artificial neural network (ANN) and support vector machine (SVM) to predict the compressive strength of bentonite/sepiolite plastic concretes. For this purpose, two unique sets of 72 data for compressive strength of bentonite and sepiolite plastic concrete samples (totally 144 data) were prepared by conducting an experimental study. The results confirm the ability of ANN and SVM models in prediction processes. Also, Sensitivity analysis of the best obtained model indicated that cement and silty clay have the maximum and minimum influences on the compressive strength, respectively. In addition, investigation of the effect of measurement error of input variables showed that change in the sand content (amount) and curing time will have the maximum and minimum effects on the output mean absolute percent error (MAPE) of model, respectively. Finally, the influence of different variables on the plastic concrete compressive strength values was evaluated by conducting parametric studies. 相似文献
10.
Tahereh Zadeh Mehrizi Mehdi Shafiee Ardestani Ali Khamesipour Mostafa Haji Molla Hoseini Nariman Mosaffa Ali Anissian Amitis Ramezani 《Journal of materials science. Materials in medicine》2018,29(8):125
Amphotericin B (A) as an antileishmanial drug has limited clinical application owing to severe side-effects and low-water solubility. This is the first study reported using Anionic Linear Globular Dendrimer (ALGD) as A carrier for the increase of A solubility rate, decrease its toxicity, and improve its therapeutic effects. ALGD was synthesized and A was loaded into nanoparticles for the first time with the drug-loading efficiency of 82%. Drug loading was confirmed using characterization methods. The drug solubility rate was increased by 478-folds. The results of the study showed that the A toxicity was significantly decreased by 95% in vitro and in vivo environments, which was confirmed by pathology findings and enzymatic evaluation. Furthermore, the nanodrug caused that mortality rate was reached to zero. Moreover, the nanodrug was as potent as the free drug and glucantime (GUL) in reducing the parasite burden and parasite number. These findings indicated the potency of ALGD to decrease the drug side-effects, increase the drug solubility rate, and improve the drug efficacy. Moreover, the nanoformulation was a non-toxic and cost-effective formulation. The conformity between in vitro and in vivo results suggested that the A-loaded ALGD could be considered as a promising candidate in reducing the side-effects of A in leishmaniasis treatment. 相似文献