Building energy modeling,also known as building energy simulation,has developed rapidly in recent years and plays a crucial role in building life-cycle analysis.It can be employed in the design phase to predict the en...Building energy modeling,also known as building energy simulation,has developed rapidly in recent years and plays a crucial role in building life-cycle analysis.It can be employed in the design phase to predict the energy consumption of different design schemes and evaluate various control and retrofitting measures at the operation stage.In such simulations,it is commonly understood and accepted that the simulated relative differences are more reliable than the predictions of absolute energy results.However,whether this common understanding is true is yet to be thoroughly investigated.In this study,we investigate the simulated relative differences and the extent to which they are affected by the degree of model input deviation.Simulation and Monte Carlo approaches are adopted for the analysis.The results indicate that the simulated relative differences are not as reliable as expected,and the outputs strongly depend on the degree of the model input deviation.When the degree of deviation is less than 15%or the model inputs are within reasonable ranges,the simulated relative differences match the baseline obtained using Monte Carlo simulations.Moreover,the model’s error indicators meet the requirements of the ASHRAE Guideline 14–2014 when the degree of input deviation is below 15%.展开更多
We report on the properties of strong pulses from PSR B0656＋14 by analyzing the data obtained using the Urumqi 25-m radio telescope at 1540 MHz from August 2007 to September 2010.In 44 h of observational data,a total...We report on the properties of strong pulses from PSR B0656＋14 by analyzing the data obtained using the Urumqi 25-m radio telescope at 1540 MHz from August 2007 to September 2010.In 44 h of observational data,a total of 67 pulses with signal-to-noise ratios above a 5σthreshold were detected.The peak flux densities of these pulses are 58 to 194 times that of the average profile,and their pulse energies are 3 to 68 times that of the average pulse.These pulses are clustered around phases about 5-ahead of the peak of the average profile.Compared with the width of the average profile,they are relatively narrow,with the full widths at half-maximum ranging from 0.28 ° to 1.78 °.The distribution of pulse-energies follows a lognormal distribution.These sporadic strong pulses detected from PSR B0656＋14 have different characteristics from both typical giant pulses and its regular pulses.展开更多
Fast pyrolysis bio-oils(fpBO)were extracted with two alternative commercial transportation fuels,hydrocarbon diesel and bio-diesel.The extraction of fpBO with commercial diesel fuel provided a yield of 4.3 wt%,but the...Fast pyrolysis bio-oils(fpBO)were extracted with two alternative commercial transportation fuels,hydrocarbon diesel and bio-diesel.The extraction of fpBO with commercial diesel fuel provided a yield of 4.3 wt%,but the yield increased significantly to 26.6 wt%when bio-diesel was the extractant.The molecular weight of fpBO before and after extraction were consistent with the loss of a more soluble,low molecular weight fraction from the crude fpBO.The relative energy difference(RED),based on the Hansen solubility parameter(HSP),is used to examine the extraction efficiency of specific compounds in the two different‘solvents’.Differences in the RED values could be used to rationalize differences in the partitioning of common fpBO phenolics.展开更多
基金supported by the“Urban Carbon Neutral”Science and Technology Innovation Fund Project from Beijing University of Technology and Beijing Postdoctoral Research Foundation.
文摘Building energy modeling,also known as building energy simulation,has developed rapidly in recent years and plays a crucial role in building life-cycle analysis.It can be employed in the design phase to predict the energy consumption of different design schemes and evaluate various control and retrofitting measures at the operation stage.In such simulations,it is commonly understood and accepted that the simulated relative differences are more reliable than the predictions of absolute energy results.However,whether this common understanding is true is yet to be thoroughly investigated.In this study,we investigate the simulated relative differences and the extent to which they are affected by the degree of model input deviation.Simulation and Monte Carlo approaches are adopted for the analysis.The results indicate that the simulated relative differences are not as reliable as expected,and the outputs strongly depend on the degree of the model input deviation.When the degree of deviation is less than 15%or the model inputs are within reasonable ranges,the simulated relative differences match the baseline obtained using Monte Carlo simulations.Moreover,the model’s error indicators meet the requirements of the ASHRAE Guideline 14–2014 when the degree of input deviation is below 15%.
基金funded by the National Natural Science Foundation of China(Grant No.10973026)
文摘We report on the properties of strong pulses from PSR B0656＋14 by analyzing the data obtained using the Urumqi 25-m radio telescope at 1540 MHz from August 2007 to September 2010.In 44 h of observational data,a total of 67 pulses with signal-to-noise ratios above a 5σthreshold were detected.The peak flux densities of these pulses are 58 to 194 times that of the average profile,and their pulse energies are 3 to 68 times that of the average pulse.These pulses are clustered around phases about 5-ahead of the peak of the average profile.Compared with the width of the average profile,they are relatively narrow,with the full widths at half-maximum ranging from 0.28 ° to 1.78 °.The distribution of pulse-energies follows a lognormal distribution.These sporadic strong pulses detected from PSR B0656＋14 have different characteristics from both typical giant pulses and its regular pulses.
基金IBSS project funded by Agriculture and Food Research Initiative Competitive Grant no.2011-68005-30410 from the USDA National Institute of Food and Agriculture.
文摘Fast pyrolysis bio-oils(fpBO)were extracted with two alternative commercial transportation fuels,hydrocarbon diesel and bio-diesel.The extraction of fpBO with commercial diesel fuel provided a yield of 4.3 wt%,but the yield increased significantly to 26.6 wt%when bio-diesel was the extractant.The molecular weight of fpBO before and after extraction were consistent with the loss of a more soluble,low molecular weight fraction from the crude fpBO.The relative energy difference(RED),based on the Hansen solubility parameter(HSP),is used to examine the extraction efficiency of specific compounds in the two different‘solvents’.Differences in the RED values could be used to rationalize differences in the partitioning of common fpBO phenolics.
