Gas-solid two-phase flow theory was used to predict dust distribution and movement at the working face of a mine.The software package FLUENT was used to numerically simulate dust motion and the results were compared t...Gas-solid two-phase flow theory was used to predict dust distribution and movement at the working face of a mine.The software package FLUENT was used to numerically simulate dust motion and the results were compared to observed data.The simulation agrees with the data taken from an actual working face,which confirms the choice of mathematical model and numerical simulation method. Using the model we predict a set of conditions optimum for reducing dust concentrations at the mine working face.展开更多
It's a subject that gets not only animal rights activists hot under the collar, but also the vast majority of caring people concerned about cruelty to animals. At a press conference in early 2006, the world's ...It's a subject that gets not only animal rights activists hot under the collar, but also the vast majority of caring people concerned about cruelty to animals. At a press conference in early 2006, the world's attention was once again drawn to the fate of Asiatic black bears (or moon bears) in China, so long tortured in the cruel practice of bile extraction. Only this展开更多
This paper investigates the use of daylight in three architecturally successful buildings.The aim is to discuss the challenges and opportunities of architectural daylight strategies in relation to integrated design.Al...This paper investigates the use of daylight in three architecturally successful buildings.The aim is to discuss the challenges and opportunities of architectural daylight strategies in relation to integrated design.All these buildings were designed with the focus on a strategy of using daylight to create well-lit,exciting spaces and spatial sequences.The original ideas,thoughts,and decisions behind the designs and daylight strategy are compared with answers in questionnaires from test subjects who have experienced the space and lighting conditions created.The results indicate that the architectural daylight strategies formulated by the architects and engineers at the beginning of the design process are actually experienced by the“users”in the existing buildings.The architectural daylight strategy was different in each of the three libraries,and analysis of the results shows that daylight strategies that include spatial considerations received more positive evaluations.Furthermore,the study showed that designs aimed at achieving an even distribution of daylight with an illuminance target of 200 lx did not result in higher evaluation of the daylight design.展开更多
Observations of sampling are often subject to rounding, but are modeled as though they were unrounded. This paper examines the impact of rounding errors on parameter estimation with multi-layer ranked set sampling. It...Observations of sampling are often subject to rounding, but are modeled as though they were unrounded. This paper examines the impact of rounding errors on parameter estimation with multi-layer ranked set sampling. It shows that the rounding errors seriously distort the behavior of covariance matrix estimate, and lead to inconsistent estimation. Taking this into account, we present a new approach to implement the estimation for this model, and further establish the strong consistency and asymptotic normality of the proposed estimators. Simulation experiments show that our estimates based on rounded multi-layer ranked set sampling are always more efficient than those based on rounded simple random sampling.展开更多
基金supported by the Special Foundation for Doctor Degree of the Ministry of Education(No.2006008001)the Construction Project of Beijing Municipal Education Committee (No.XK100080432)the Joint Development Project of Beijing.
文摘Gas-solid two-phase flow theory was used to predict dust distribution and movement at the working face of a mine.The software package FLUENT was used to numerically simulate dust motion and the results were compared to observed data.The simulation agrees with the data taken from an actual working face,which confirms the choice of mathematical model and numerical simulation method. Using the model we predict a set of conditions optimum for reducing dust concentrations at the mine working face.
文摘It's a subject that gets not only animal rights activists hot under the collar, but also the vast majority of caring people concerned about cruelty to animals. At a press conference in early 2006, the world's attention was once again drawn to the fate of Asiatic black bears (or moon bears) in China, so long tortured in the cruel practice of bile extraction. Only this
文摘This paper investigates the use of daylight in three architecturally successful buildings.The aim is to discuss the challenges and opportunities of architectural daylight strategies in relation to integrated design.All these buildings were designed with the focus on a strategy of using daylight to create well-lit,exciting spaces and spatial sequences.The original ideas,thoughts,and decisions behind the designs and daylight strategy are compared with answers in questionnaires from test subjects who have experienced the space and lighting conditions created.The results indicate that the architectural daylight strategies formulated by the architects and engineers at the beginning of the design process are actually experienced by the“users”in the existing buildings.The architectural daylight strategy was different in each of the three libraries,and analysis of the results shows that daylight strategies that include spatial considerations received more positive evaluations.Furthermore,the study showed that designs aimed at achieving an even distribution of daylight with an illuminance target of 200 lx did not result in higher evaluation of the daylight design.
基金The second author is supported by National Natural Science Foundation of China （Grant No. 10871036）
文摘Observations of sampling are often subject to rounding, but are modeled as though they were unrounded. This paper examines the impact of rounding errors on parameter estimation with multi-layer ranked set sampling. It shows that the rounding errors seriously distort the behavior of covariance matrix estimate, and lead to inconsistent estimation. Taking this into account, we present a new approach to implement the estimation for this model, and further establish the strong consistency and asymptotic normality of the proposed estimators. Simulation experiments show that our estimates based on rounded multi-layer ranked set sampling are always more efficient than those based on rounded simple random sampling.
