The standalone Global Positioning System (GPS) does not meet the higher accuracy requirements needed for approach and landing phase of an aircraft. To meet the Category-I Precision Approach (CAT-I PA) requirements of ...The standalone Global Positioning System (GPS) does not meet the higher accuracy requirements needed for approach and landing phase of an aircraft. To meet the Category-I Precision Approach (CAT-I PA) requirements of civil aviation, satellite based augmentation system (SBAS) has been planned by various countries including USA, Europe, Japan and India. The Indian SBAS is named as GPS Aided Geo Augmented Navigation (GAGAN). The GAGAN network consists of several dual frequency GPS receivers located at various airports around the Indian subcontinent. The ionospheric delay, which is a function of the total electron content (TEC), is one of the main sources of error affecting GPS/SBAS accuracy. A dual frequency GPS receiver can be used to estimate the TEC. However, line-of-sight TEC derived from dual frequency GPS data is corrupted by the instrumental biases of the GPS receiver and satellites. The estimation of receiver instrumental bias is particularly important for obtaining accurate estimates of ionospheric delay. In this paper, two prominent techniques based on Kalman filter and Self-Calibration Of pseudo Range Error (SCORE) algorithm are used for estimation of instrumental biases. The estimated instrumental bias and TEC results for the GPS Aided Geo Augmented Navigation (GAGAN) station at Hyderabad (78.47°E, 17.45°N), India are presented.展开更多
考虑系数矩阵含非随机元素和不同位置含相同随机元素的结构化特征,PEIV (partial errors-in-variables)模型较一般的EIV模型更为严格。现有PEIV模型加权整体最小二乘(weighted total least squares,WTLS)估计算法需多次迭代,影响计算效...考虑系数矩阵含非随机元素和不同位置含相同随机元素的结构化特征,PEIV (partial errors-in-variables)模型较一般的EIV模型更为严格。现有PEIV模型加权整体最小二乘(weighted total least squares,WTLS)估计算法需多次迭代,影响计算效率。通过利用观测值误差和系数矩阵误差的统计性质构造非线性目标函数,并以此推导了新的PEIV模型WTLS估计的计算公式,同时设计了相应的Fisher-Score算法。算例分析结果表明,相比较而言,Fisher-Score算法迭代次数较少,计算效率得到大大提升。展开更多
针对传统鱼糕货架期短、运输条件苛刻、食用方法单一等问题,本研究通过配方优化与真空冷冻干燥技术开发新型鱼糕产品,旨在延长其保质期、提升营养均衡性并拓展即食化、多场景应用潜力,同时为水产制品的工业化加工提供工艺参考。以鲢鱼...针对传统鱼糕货架期短、运输条件苛刻、食用方法单一等问题,本研究通过配方优化与真空冷冻干燥技术开发新型鱼糕产品,旨在延长其保质期、提升营养均衡性并拓展即食化、多场景应用潜力,同时为水产制品的工业化加工提供工艺参考。以鲢鱼为主要原料,基于层次分析-熵权法构建综合评分模型,选择猪肥肉、鸡肉、玉米淀粉和蛋清添加量进行单因素实验,并在单因素实验基础上通过遗传算法结合Box-Behnken响应面法对鱼糕冻干配方进行优化。通过扫描电子显微镜(scanning electron microscopy,SEM)分析微观结构,测定蛋白质、脂肪、水分、灰分等理化指标,并基于Arrhenius方程预测货架期。确定了鱼糕冻干最优配方为:相对碎鱼肉用量,猪肥肉添加量10%(质量分数),鸡肉添加量20%,玉米淀粉添加量11%,蛋清添加量8%,综合评分达0.87±0.34。微观结构显示孔隙分布均匀,真空冷冻干燥处理前后关键理化指标无显著变化。基于Arrhenius方程的货架期模型预测25℃贮藏期为77 d,较鲜切鱼糕(4~7 d)延长11倍。本研究得到了色泽均匀、口感酥脆、货架期长以及营养均衡的鱼糕冻干制品,为鱼糕制品常温储运与即食化应用提供借鉴。展开更多
Quality of experience ( QoE ) based scheduling algorithm of long term evalution ( LTE ) network with various traffics is studied. Utility functions are adopted to estimate mean opinion score (MOS) for different ...Quality of experience ( QoE ) based scheduling algorithm of long term evalution ( LTE ) network with various traffics is studied. Utility functions are adopted to estimate mean opinion score (MOS) for different traffics and a new MOS metric called normalized MOS is defined. A scheduling algorithm based on normalized MOS and greedy algorithm is proposed, aiming at maximizing the entirety MOS level of the whole users in the cell. We compare the performance of the proposed algorithm with other typical scheduling algorithms and the simulation results show that the algorithm pro- posed outperform other ones in term of QoE and fairness.展开更多
In order to improve the fitting accuracy of college students’ test scores, this paper proposes two-component mixed generalized normal distribution, uses maximum likelihood estimation method and Expectation Conditiona...In order to improve the fitting accuracy of college students’ test scores, this paper proposes two-component mixed generalized normal distribution, uses maximum likelihood estimation method and Expectation Conditional Maxinnization (ECM) algorithm to estimate parameters and conduct numerical simulation, and performs fitting analysis on the test scores of Linear Algebra and Advanced Mathematics of F University. The empirical results show that the two-component mixed generalized normal distribution is better than the commonly used two-component mixed normal distribution in fitting college students’ test data, and has good application value.展开更多
The structure and function of proteins are closely related, and protein structure decides its function, therefore protein structure prediction is quite important.β-turns are important components of protein secondary ...The structure and function of proteins are closely related, and protein structure decides its function, therefore protein structure prediction is quite important.β-turns are important components of protein secondary structure. So development of an accurate prediction method ofβ-turn types is very necessary. In this paper, we used the composite vector with position conservation scoring function, increment of diversity and predictive secondary structure information as the input parameter of support vector machine algorithm for predicting theβ-turn types in the database of 426 protein chains, obtained the overall prediction accuracy of 95.6%, 97.8%, 97.0%, 98.9%, 99.2%, 91.8%, 99.4% and 83.9% with the Matthews Correlation Coefficient values of 0.74, 0.68, 0.20, 0.49, 0.23, 0.47, 0.49 and 0.53 for types I, II, VIII, I’, II’, IV, VI and nonturn respectively, which is better than other prediction.展开更多
文摘The standalone Global Positioning System (GPS) does not meet the higher accuracy requirements needed for approach and landing phase of an aircraft. To meet the Category-I Precision Approach (CAT-I PA) requirements of civil aviation, satellite based augmentation system (SBAS) has been planned by various countries including USA, Europe, Japan and India. The Indian SBAS is named as GPS Aided Geo Augmented Navigation (GAGAN). The GAGAN network consists of several dual frequency GPS receivers located at various airports around the Indian subcontinent. The ionospheric delay, which is a function of the total electron content (TEC), is one of the main sources of error affecting GPS/SBAS accuracy. A dual frequency GPS receiver can be used to estimate the TEC. However, line-of-sight TEC derived from dual frequency GPS data is corrupted by the instrumental biases of the GPS receiver and satellites. The estimation of receiver instrumental bias is particularly important for obtaining accurate estimates of ionospheric delay. In this paper, two prominent techniques based on Kalman filter and Self-Calibration Of pseudo Range Error (SCORE) algorithm are used for estimation of instrumental biases. The estimated instrumental bias and TEC results for the GPS Aided Geo Augmented Navigation (GAGAN) station at Hyderabad (78.47°E, 17.45°N), India are presented.
文摘考虑系数矩阵含非随机元素和不同位置含相同随机元素的结构化特征,PEIV (partial errors-in-variables)模型较一般的EIV模型更为严格。现有PEIV模型加权整体最小二乘(weighted total least squares,WTLS)估计算法需多次迭代,影响计算效率。通过利用观测值误差和系数矩阵误差的统计性质构造非线性目标函数,并以此推导了新的PEIV模型WTLS估计的计算公式,同时设计了相应的Fisher-Score算法。算例分析结果表明,相比较而言,Fisher-Score算法迭代次数较少,计算效率得到大大提升。
文摘针对传统鱼糕货架期短、运输条件苛刻、食用方法单一等问题,本研究通过配方优化与真空冷冻干燥技术开发新型鱼糕产品,旨在延长其保质期、提升营养均衡性并拓展即食化、多场景应用潜力,同时为水产制品的工业化加工提供工艺参考。以鲢鱼为主要原料,基于层次分析-熵权法构建综合评分模型,选择猪肥肉、鸡肉、玉米淀粉和蛋清添加量进行单因素实验,并在单因素实验基础上通过遗传算法结合Box-Behnken响应面法对鱼糕冻干配方进行优化。通过扫描电子显微镜(scanning electron microscopy,SEM)分析微观结构,测定蛋白质、脂肪、水分、灰分等理化指标,并基于Arrhenius方程预测货架期。确定了鱼糕冻干最优配方为:相对碎鱼肉用量,猪肥肉添加量10%(质量分数),鸡肉添加量20%,玉米淀粉添加量11%,蛋清添加量8%,综合评分达0.87±0.34。微观结构显示孔隙分布均匀,真空冷冻干燥处理前后关键理化指标无显著变化。基于Arrhenius方程的货架期模型预测25℃贮藏期为77 d,较鲜切鱼糕(4~7 d)延长11倍。本研究得到了色泽均匀、口感酥脆、货架期长以及营养均衡的鱼糕冻干制品,为鱼糕制品常温储运与即食化应用提供借鉴。
基金Supported by China National S&T Major Project(2013ZX03003002-003)Beijing Natural Science Foundation(4152047)National High Technology Research and Development Program of China(863Program)(2014AA01A701)
文摘Quality of experience ( QoE ) based scheduling algorithm of long term evalution ( LTE ) network with various traffics is studied. Utility functions are adopted to estimate mean opinion score (MOS) for different traffics and a new MOS metric called normalized MOS is defined. A scheduling algorithm based on normalized MOS and greedy algorithm is proposed, aiming at maximizing the entirety MOS level of the whole users in the cell. We compare the performance of the proposed algorithm with other typical scheduling algorithms and the simulation results show that the algorithm pro- posed outperform other ones in term of QoE and fairness.
文摘In order to improve the fitting accuracy of college students’ test scores, this paper proposes two-component mixed generalized normal distribution, uses maximum likelihood estimation method and Expectation Conditional Maxinnization (ECM) algorithm to estimate parameters and conduct numerical simulation, and performs fitting analysis on the test scores of Linear Algebra and Advanced Mathematics of F University. The empirical results show that the two-component mixed generalized normal distribution is better than the commonly used two-component mixed normal distribution in fitting college students’ test data, and has good application value.
文摘The structure and function of proteins are closely related, and protein structure decides its function, therefore protein structure prediction is quite important.β-turns are important components of protein secondary structure. So development of an accurate prediction method ofβ-turn types is very necessary. In this paper, we used the composite vector with position conservation scoring function, increment of diversity and predictive secondary structure information as the input parameter of support vector machine algorithm for predicting theβ-turn types in the database of 426 protein chains, obtained the overall prediction accuracy of 95.6%, 97.8%, 97.0%, 98.9%, 99.2%, 91.8%, 99.4% and 83.9% with the Matthews Correlation Coefficient values of 0.74, 0.68, 0.20, 0.49, 0.23, 0.47, 0.49 and 0.53 for types I, II, VIII, I’, II’, IV, VI and nonturn respectively, which is better than other prediction.