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101.
Vishal Garg Akshey Jawa Jyotirmay Mathur Aviruch Bhatia 《Journal of Building Performance Simulation》2014,7(3):179-191
This paper describes how the EPparallel tool splits a single annual simulation into 12 simulations of one month each and runs them in parallel. The paper also describes the methodology to prepare input files, enable file sharing between nodes, collate results generated by the nodes, and ensure quality check on the simulations. The EPparallel tool uses Message Passing Interface library and runs on Linux. The tool has been tested on 16 commercial reference buildings over 16 US weather files. The results of these 256 runs which include the run times, computing time overheads, speed gains and accuracy of results are presented in this paper. The speed gain ranged from 2.9×to 7.8×and deviation (percentage of output values obtained in parallel simulation which were off by more than 1% as compared to output values obtained in annual simulation) ranged from 0% to 4%. 相似文献
102.
Anuj Kumar K. V. Sharma Arun Gupta Jan Tywoniak Petr Hajek 《Holz als Roh- und Werkstoff》2017,75(2):203-213
In the present work, medium density fiberboard (MDF) panels were produced using multiwalled carbon nanotubes (MWCNT) reinforced urea formaldehyde resin. Response surface methodology was employed to optimize the relationship between the three variables, viz. pressing time, percentage of UF resin and percentage of MWCNT, used in the fabrication of MDF, and the influence of variables on the internal bonding (IB) and modulus of rupture (MOR) was studied. The optimum conditions based on the IB strength were determined as 8.18 % of UF resin, pressing time of 232 s, and MWCNT of 3.5 %. Similarly, the optimized conditions for MOR are also reported in this paper. 相似文献
103.
Srinivasan Arjun Tekalur Arun Shukla Martin Sadd K. Wayne Lee 《Construction and Building Materials》2009,23(5):1795-1802
There are various methods to determine the compressive and tensile strength of asphalt concrete under static loading conditions and most studies on asphalt strength and fracture have been conducted under such loading conditions. However, pavement materials also have to withstand a wide variety of loading and temperature conditions which may vary from quasi-static to high-strain rate impact, and pavement breakdown may occur due to fracture and/or fatigue failure. In the present study, a bituminous mix with 30% RAP has been characterized under quasi-static (10?3–10?4 strain/s) and high-strain rate (200–700 strain/s) regimes. The experimental studies have been performed to better understand the compressive, tensile and fracture response of bituminous mixes. Split Hopkinson pressure bar (SHPB) and its modifications were used for high-strain rate characterization of this bituminous mixture. It was observed that the mechanical properties of the hot mix asphalt (HMA) changed significantly under high-strain rate testing. Also, the failure mechanisms observed under the high-strain rate loading were found to be considerably different from those obtained in static testing, where failure of binder was a predominant mechanism. It was observed that high-strain rate loading caused trans-aggregate failures in the specimens; in addition to failure of the binder. 相似文献
104.
A 2D model for the potential distribution in silicon film is derived for a symmetrical double gate MOSFET in weak inversion. This 2D potential distribution model is used to analytically derive an expression for the subthreshold slope and threshold voltage. A drain current model for lightly doped symmetrical DG MOSFETs is then presented by considering weak and strong inversion regions including short channel effects, series source to drain resistance and channel length modulation parameters. These derived models are compared with the simulation results of the SILVACO (Atlas) tool for different channel lengths and silicon film thicknesses. Lastly, the effect of the fixed oxide charge on the drain current model has been studied through simulation. It is observed that the obtained analytical models of symmetrical double gate MOSFETs are in good agreement with the simulated results for a channel length to silicon film thickness ratio greater than or equal to 2. 相似文献
105.
Naira V. Margaryan Alina Gilgur Elisabeth A. Seftor Chad Purnell Nicoleta C. Arva Arun K. Gosain Mary J. C. Hendrix Luigi Strizzi 《International journal of molecular sciences》2016,17(3)
Expression of Nodal, a Transforming Growth Factor-beta (TGF-β) related growth factor, is associated with aggressive melanoma. Nodal expression in adult dysplastic nevi may predict the development of aggressive melanoma in some patients. A subset of pediatric patients diagnosed with giant or large congenital melanocytic nevi (LCMN) has shown increased risk for development of melanoma. Here, we investigate whether Nodal expression can help identify the rare cases of LCMN that develop melanoma and shed light on why the majority of these patients do not. Immunohistochemistry (IHC) staining results show varying degree of Nodal expression in pediatric dysplastic nevi and LCMN. Moreover, median scores from Nodal IHC expression analysis were not significantly different between these two groups. Additionally, none of the LCMN patients in this study developed melanoma, regardless of Nodal IHC levels. Co-culture experiments revealed reduced tumor growth and lower levels of Nodal and its signaling molecules P-SMAD2 and P-ERK1/2 when melanoma cells were grown in vivo or in vitro with normal melanocytes. The same was observed in melanoma cells cultured with melanocyte conditioned media containing pigmented melanocyte derived melanosomes (MDM). Since MDM contain molecules capable of inactivating radical oxygen species, to investigate potential anti-oxidant effect of MDM on Nodal expression and signaling in melanoma, melanoma cells were treated with either N-acetyl-l-cysteine (NAC), a component of the anti-oxidant glutathione or synthetic melanin, which in addition to providing pigmentation can also exert free radical scavenging activity. Melanoma cells treated with NAC or synthetic melanin showed reduced levels of Nodal, P-SMAD2 and P-ERK1/2 compared to untreated melanoma cells. Thus, the potential role for Nodal in melanoma development in LCMN is less evident than in adult dysplastic nevi possibly due to melanocyte cross-talk in LCMN capable of offsetting or delaying the pro-melanoma effects of Nodal via anti-oxidant effects of MDM. 相似文献
106.
107.
Silicon - Tunnel Field Effect Transistor can be introduced as an emerging alternate to MOSFET which is energy efficient and can be used in low power applications. Due to the challenge involved in... 相似文献
108.
Three alternate dying methods—vacuum drying (VD), vacuum microwave drying (VMD), and pulse-spouted vacuum–microwave drying (PSVMD)—were examined experimentally for their potential as an industrial scale technology to produce granules of fish. Drying kinetics as well as key quality parameters such as expansion ratio, texture, color, sensory characteristics, and microstructure of crispy granules produced by these drying techniques were examined. Results showed that the drying time is reduced with an increase in microwave power level and with reduced pressure as expected. The quality of the granules is affected by the drying method and the operating parameters employed. Granules obtained using PSVMD at a microwave power density of 6.0 W/g displayed optimal quality required for the commercial product accepted by consumers. 相似文献
109.
Non-uniform heating is a major issue in microwave applications, mainly due to inherently uneven distribution of electromagnetic energy in the microwave applicator. In this work, our aim is to improve electric field distribution uniformity by utilizing microwave reflection from electrically conductive beads placed in the microwave oven. The effects of position, size, and number of electrically conductive beads on the electric field distribution were numerically investigated, and validated through water-load experiments in the cavity. It is found that uniform electric field distribution was realized to some extent by appropriate placement of electrically conductive beads; meanwhile, average electric field intensity in the microwave oven was increased. 相似文献
110.
The drying homogeneity of the microwave–pulsed spouted bed drying (MPSBD) method was studied via preparing tubers granules by MPSBD under different predefined conditions. The effects of three parameters (microwave power, moisture content transition point, and loading) on the homogeneity of prepared tubers granules were studied. Based on response surface analysis results, it was concluded that the optimum conditions for tuber granules prepared by MPSBD method is 1.10 W/g microwave power, 80% moisture content transition point, and 90 g material loading. It was proven that the experimental result from the predicted optimal condition agreed with the model-predicted results, which evidenced the accuracy of the response surface analysis. Furthermore, the brighter color and higher rehydration capacity of samples prepared by MPSBD indicates that MPSBD is a promising method that can be applied in the food dehydration industry. 相似文献