Uncertainty on the geological contacts and the block volumes of the models along boundaries is often a major part of the global uncertainty of reserve estimation.This work introduces a geostatistical technique that ha...Uncertainty on the geological contacts and the block volumes of the models along boundaries is often a major part of the global uncertainty of reserve estimation.This work introduces a geostatistical technique that has been developed and tested in an iron ore deposit at Bafq mining district,in central Iran,and that,based on a probability criterion,helps to objectively model the geometry of this iron ore deposit.The main problem in reserve estimation of this ore body is its geometrical modeling and uncertainty in geological boundaries.This work deals with the geostatistical method of multiple indicator kriging,which is used to determine the real boundaries of ore body in different categories.This approach has potential to improve project performance and decrease operational risk.For this purpose,the ore body is separated into two categories including rich iron zone(w(Fe)>45%)and poor iron zone(20%<w(Fe)<45%).It significantly benefits to decrease the risk of reserve evaluation in the deposit.This case study also highlights the value of multiple indicator kriging as a tool for estimates the position of grade boundaries within the deposit.Comparison of the resultant probability maps with the real ore/waste contacts on the extracted levels shows that the first indicator model could separate the whole ore body(poor plus rich)from the waste zone by probability of more than 0.35,which concludes the total reserve of 53 million tons.The second indicator model applied to separate the rich and poor domains and the results show that the blocks with the estimated probability of equal to or more than 0.4 lay within the rich ore zone consisting of 15.8 million tons reserve.展开更多
为系统研究心理潜在因素与外生因素对短距离下小汽车出行向自行车出行转移意向的影响,提出了转移意向多指标多原因(multiple indicators and multiple causes,MIMIC)模型.以计划行为理论为框架拓展潜在因素,研究外部障碍、个人障碍、骑...为系统研究心理潜在因素与外生因素对短距离下小汽车出行向自行车出行转移意向的影响,提出了转移意向多指标多原因(multiple indicators and multiple causes,MIMIC)模型.以计划行为理论为框架拓展潜在因素,研究外部障碍、个人障碍、骑行态度、骑行偏好、主观规范与转移意向潜在变量间的相互影响关系,并分析社会人口特征、出行特征、客观环境、小汽车限制措施等外生变量与潜在变量间的因果关系.结果表明:通过外部障碍、个人障碍、骑行偏好、骑行态度和主观规范能够有效解释小汽车出行向自行车出行转移意向,转移意向受到外部障碍、个人障碍、骑行偏好和主观规范的直接影响,以及外部障碍、主观规范和骑行态度的间接影响;外生变量对转移意向不产生直接影响,而是通过其他潜在变量对转移意向产生间接影响;外部障碍、骑行态度是客观环境与转移意向间的完全中介变量,骑行态度、骑行偏好是小汽车限制措施与转移意向间的完全中介变量,说明通过干预措施提升人们对环境的感知至关重要,通过小汽车限制措施提升态度与偏好是推进转移的重要手段.展开更多
针对煤矿井下无线信道的信号传播模型,提出将接收信号强度复合滤波器、一元线性回归测距模型和多边定位方法相结合的改进接收信号强度指示(Received Signal Strength Indicator,RSSI)值的井下定位技术,通过利用基于无线传感器网络操作系...针对煤矿井下无线信道的信号传播模型,提出将接收信号强度复合滤波器、一元线性回归测距模型和多边定位方法相结合的改进接收信号强度指示(Received Signal Strength Indicator,RSSI)值的井下定位技术,通过利用基于无线传感器网络操作系统TinyOS的节点进行离线建模、在线测算,实现煤矿井下人员及设备的实时定位。井下巷道试验表明,该技术提高了定位精度,增强了定位系统的鲁棒性,适用于煤矿井下定位。展开更多
基金supported by Iron Ore Research Center of Yazd University
文摘Uncertainty on the geological contacts and the block volumes of the models along boundaries is often a major part of the global uncertainty of reserve estimation.This work introduces a geostatistical technique that has been developed and tested in an iron ore deposit at Bafq mining district,in central Iran,and that,based on a probability criterion,helps to objectively model the geometry of this iron ore deposit.The main problem in reserve estimation of this ore body is its geometrical modeling and uncertainty in geological boundaries.This work deals with the geostatistical method of multiple indicator kriging,which is used to determine the real boundaries of ore body in different categories.This approach has potential to improve project performance and decrease operational risk.For this purpose,the ore body is separated into two categories including rich iron zone(w(Fe)>45%)and poor iron zone(20%<w(Fe)<45%).It significantly benefits to decrease the risk of reserve evaluation in the deposit.This case study also highlights the value of multiple indicator kriging as a tool for estimates the position of grade boundaries within the deposit.Comparison of the resultant probability maps with the real ore/waste contacts on the extracted levels shows that the first indicator model could separate the whole ore body(poor plus rich)from the waste zone by probability of more than 0.35,which concludes the total reserve of 53 million tons.The second indicator model applied to separate the rich and poor domains and the results show that the blocks with the estimated probability of equal to or more than 0.4 lay within the rich ore zone consisting of 15.8 million tons reserve.
文摘为系统研究心理潜在因素与外生因素对短距离下小汽车出行向自行车出行转移意向的影响,提出了转移意向多指标多原因(multiple indicators and multiple causes,MIMIC)模型.以计划行为理论为框架拓展潜在因素,研究外部障碍、个人障碍、骑行态度、骑行偏好、主观规范与转移意向潜在变量间的相互影响关系,并分析社会人口特征、出行特征、客观环境、小汽车限制措施等外生变量与潜在变量间的因果关系.结果表明:通过外部障碍、个人障碍、骑行偏好、骑行态度和主观规范能够有效解释小汽车出行向自行车出行转移意向,转移意向受到外部障碍、个人障碍、骑行偏好和主观规范的直接影响,以及外部障碍、主观规范和骑行态度的间接影响;外生变量对转移意向不产生直接影响,而是通过其他潜在变量对转移意向产生间接影响;外部障碍、骑行态度是客观环境与转移意向间的完全中介变量,骑行态度、骑行偏好是小汽车限制措施与转移意向间的完全中介变量,说明通过干预措施提升人们对环境的感知至关重要,通过小汽车限制措施提升态度与偏好是推进转移的重要手段.
文摘针对煤矿井下无线信道的信号传播模型,提出将接收信号强度复合滤波器、一元线性回归测距模型和多边定位方法相结合的改进接收信号强度指示(Received Signal Strength Indicator,RSSI)值的井下定位技术,通过利用基于无线传感器网络操作系统TinyOS的节点进行离线建模、在线测算,实现煤矿井下人员及设备的实时定位。井下巷道试验表明,该技术提高了定位精度,增强了定位系统的鲁棒性,适用于煤矿井下定位。
