为了提高用于更新代理模型的解集的多样性和收敛性以提高代理模型准确度,提出一种基于行列式点过程(determinantal point process,DPP)的代理模型辅助多目标进化算法(surrogate-assisted evolutionary algorithm,SAEA)。首先,提出一种...为了提高用于更新代理模型的解集的多样性和收敛性以提高代理模型准确度,提出一种基于行列式点过程(determinantal point process,DPP)的代理模型辅助多目标进化算法(surrogate-assisted evolutionary algorithm,SAEA)。首先,提出一种基于行列式点过程的模型管理方法,从非支配解集基于行列式点过程选取子集并用真实目标函数评估,再从所有经真实目标函数评估的解中选取子集用于更新代理模型。另一方面,提出一种基于自适应行列式点过程的环境选择方法,在进化过程的早期侧重于提高种群的收敛性,在进化过程的后期侧重于提高种群的多样性。最后,基于DTLZ、WFG、MAF测试问题验证算法的有效性。将所提算法与K-RVEA、KTA2、CSEA等常用算法进行比较,使用IGD+指标进行评估。实验结果显示所提出的算法能得到更优的解集,从而证明了其高计算代价多目标优化问题上的有效性。展开更多
A new method was developed for determination of 407 pesticide residues in complex matrix by using LC-MS with triple quadrupole(QQQ).Comparing with regular method,the method has high sensitivity and repeativity,and was...A new method was developed for determination of 407 pesticide residues in complex matrix by using LC-MS with triple quadrupole(QQQ).Comparing with regular method,the method has high sensitivity and repeativity,and was applied for the determination of peticide in real sample with satisfactory results.展开更多
Various trace elements, especially potential toxic trace elements such as As, Cd, Cr, Cu, Hg, Pb, Ni, Se, Tl, Zn, would be concentrated in processing of coal. Determination of these elements in coal is very important ...Various trace elements, especially potential toxic trace elements such as As, Cd, Cr, Cu, Hg, Pb, Ni, Se, Tl, Zn, would be concentrated in processing of coal. Determination of these elements in coal is very important for identification of coal quality. A method is developed for determination of 49 trace elements in coal by high resolution inductively coupled plasma mass spectrometry (HR-ICPMS). Microwave acid digestion and low-temperature airproof acid digestion for sample preparation were investigated. It is shown that the low-temperature airproof acid digestion method is of lower blank, and more suitalbe for the coal sample preparation. The on-line internal standard (Rh) sample introduction is applied to compensate matrix effects in measurement by ICPMS. The method gives low detection limits (0.002-1.60 μg/g) and better relative standard deviations (0.60%-4.78%) for the determined 49 elements in coal.展开更多
A GC-MS method was established for determination of 10 pyrethroids in apple juice concentrate.The sample was extracted by acetone and hexane,and the 10 pyrethroids were separated on a capillary column(DB-5,30 m×2...A GC-MS method was established for determination of 10 pyrethroids in apple juice concentrate.The sample was extracted by acetone and hexane,and the 10 pyrethroids were separated on a capillary column(DB-5,30 m×250 μm×0.25 μm) and determined by GC-MSD.The recoveries of pyrethroids were range of 84%-96% with the detection limits of 3-46 μg/kg.The relative standard deviations were range of 0.68%-5.11%.展开更多
A direct determination method for the atrazine residue on the vegetable was developed by using desorption electrospray ionization mass spectrometry (DESI MS) without any sample pretreatment.Acetonitrile-water (1:1,v/v...A direct determination method for the atrazine residue on the vegetable was developed by using desorption electrospray ionization mass spectrometry (DESI MS) without any sample pretreatment.Acetonitrile-water (1:1,v/v),which contained 0.1% formic acid,was used as the spray solvent.The working conditions,such as ESI gas inlet pressure,ESI flow rate,ESI spray voltage,spray-to-sample distance,spray-to-cone-hole distance and the collision induced dissociation (CID) voltage for MS/MS,were optimized for both DESI and esquires 6 000 mass spectrometer.The linear range of atrazine on cabbage leaves was 25.25-2 525 pg/mm2,the R2 was 0.991 6,and the relative standard deviations were between 3.37% and 26.17%.The LOD of atrazine calculated by S/N=3 was 2.50 pg/mm2.展开更多
A high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICPMS) was combined, and the chromatography conditions were optimized. The stability and homogeneity of a trimethyllead refer...A high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICPMS) was combined, and the chromatography conditions were optimized. The stability and homogeneity of a trimethyllead reference material were determined using this method.展开更多
In human subjects,morphine is extensively metabolized to form(M3G)and morphine-6-glucuronide(M6G).This article established a sensitive LC-MS/MS method that allows the quantification of morphine and its glucuronide met...In human subjects,morphine is extensively metabolized to form(M3G)and morphine-6-glucuronide(M6G).This article established a sensitive LC-MS/MS method that allows the quantification of morphine and its glucuronide metabolites.展开更多
A method for simultaneous determination of oxytetracycline,tetracycline,chlortetracycline in animal tissue was successfully established by HPLC-ESI MS/MS.The tetracycline antibiotics in animal tissue were extracted by...A method for simultaneous determination of oxytetracycline,tetracycline,chlortetracycline in animal tissue was successfully established by HPLC-ESI MS/MS.The tetracycline antibiotics in animal tissue were extracted by liquid-solid extraction and cleaned up by SPE.The mass spectrometer was operated in the positive-ion mode using selected reaction monitoring(SRM).The results showed that three tetracycline antibiotics were well separated under the optimal conditions.The detection limits of oxytetracycline,tetracycline and chlortetracycline were 0.16 ng/g,0.1 ng/g and 0.1 ng/g,respectively.The spiked recoveries were range of 84%-94% and the relative standard deviations were 2.4%-2.9%.展开更多
Background&Objective Tumor-associated macrophages(TAM)are induced by many cytokines,such as IL-4,IL-10,IL-13,and are considered to be of the M2 phenotype,which provides an immunosuppressive microenvironment for tu...Background&Objective Tumor-associated macrophages(TAM)are induced by many cytokines,such as IL-4,IL-10,IL-13,and are considered to be of the M2 phenotype,which provides an immunosuppressive microenvironment for tumor growth.However,biomechanistssuggest that cells in the tumor microenvironment are affected not only by chemical signals but also mechanical factors,of which the stiffness of tissues is a major determinant.Compared with normal tissues,including the peri-tumor tissues,tumor tissues are more rigid.Heretofore,the influence,on the differentiation and function of macrophages,of the differences in such physical aspect between展开更多
针对现有的作战需求表征与作战方案评价存在不确定性信息、作战方案设计中经验积累与重用以及作战方案推荐中相关性与多样性权衡问题,提出了一种不确定信息下考虑相关性与多样性的作战方案推荐方法。首先,将粗糙集理论融入最优最劣法(be...针对现有的作战需求表征与作战方案评价存在不确定性信息、作战方案设计中经验积累与重用以及作战方案推荐中相关性与多样性权衡问题,提出了一种不确定信息下考虑相关性与多样性的作战方案推荐方法。首先,将粗糙集理论融入最优最劣法(best-worst method,BWM)中对各作战能力属性进行赋权;其次,给出了不确定信息下作战方案与任务需求之间的相关性、作战方案之间的多样性计算模型;然后,提出了权衡相关性和多样性的行列式点过程(determinantal point process,DPP)模型,在此基础上,给出了贪婪最大后验概率(maximum a posterior,MAP)推断算法和贪婪Trade-off推断算法以获得作战方案最优推荐子集;最后,通过案例分析验证了所提模型和方法的适用性和可行性。展开更多
A method for the simultaneous determination of β2-agonists residues was developed by LC-MS/MS.The results indicated that the calibration curves showed good linear range from 0.1 g/L to 10 g/L for 11 β2-agonists.The ...A method for the simultaneous determination of β2-agonists residues was developed by LC-MS/MS.The results indicated that the calibration curves showed good linear range from 0.1 g/L to 10 g/L for 11 β2-agonists.The spiked recoveries were between 79% and 110%.The method was rapid,accurate,and was suitable for the determination of β2-agonists in animal food.展开更多
针对大多数的图像自动标注结果中含有冗余标签、信息量不够丰富的问题,本文提出了一种基于级联网络和语义层次结构的图像自动标注方法(CNSH)。首先,输入数据集的图片和标签列表,采用级联的VGG网络提取图像特征,训练条件行列式点过程(DPP...针对大多数的图像自动标注结果中含有冗余标签、信息量不够丰富的问题,本文提出了一种基于级联网络和语义层次结构的图像自动标注方法(CNSH)。首先,输入数据集的图片和标签列表,采用级联的VGG网络提取图像特征,训练条件行列式点过程(DPP)算法模型,计算标签的质量分数确定候选标签列表;其次,利用WordNet检索数据集标签得到语义层次结构和同义词,进而构建加权语义路径;最后,利用DPP算法在候选标签集中采样,得到最终的标注结果。与传统的图像标注任务相比,本文方法得到的标注结果能准确描述图片内容,且不含冗余标签。许多评估指标已用于图像标注和多标签学习,但是它们只专注于评估代表性,忽略了多样性。为了解决上述问题,本文采用了基于语义层次结构的语义指标来共同评估代表性和多样性。在IAPRTC-12和ESP Game 2个基准数据集上的实验表明,与现有方法相比本文方法能够产生更具代表性和多样性的标签。展开更多
文摘为了提高用于更新代理模型的解集的多样性和收敛性以提高代理模型准确度,提出一种基于行列式点过程(determinantal point process,DPP)的代理模型辅助多目标进化算法(surrogate-assisted evolutionary algorithm,SAEA)。首先,提出一种基于行列式点过程的模型管理方法,从非支配解集基于行列式点过程选取子集并用真实目标函数评估,再从所有经真实目标函数评估的解中选取子集用于更新代理模型。另一方面,提出一种基于自适应行列式点过程的环境选择方法,在进化过程的早期侧重于提高种群的收敛性,在进化过程的后期侧重于提高种群的多样性。最后,基于DTLZ、WFG、MAF测试问题验证算法的有效性。将所提算法与K-RVEA、KTA2、CSEA等常用算法进行比较,使用IGD+指标进行评估。实验结果显示所提出的算法能得到更优的解集,从而证明了其高计算代价多目标优化问题上的有效性。
文摘A new method was developed for determination of 407 pesticide residues in complex matrix by using LC-MS with triple quadrupole(QQQ).Comparing with regular method,the method has high sensitivity and repeativity,and was applied for the determination of peticide in real sample with satisfactory results.
文摘Various trace elements, especially potential toxic trace elements such as As, Cd, Cr, Cu, Hg, Pb, Ni, Se, Tl, Zn, would be concentrated in processing of coal. Determination of these elements in coal is very important for identification of coal quality. A method is developed for determination of 49 trace elements in coal by high resolution inductively coupled plasma mass spectrometry (HR-ICPMS). Microwave acid digestion and low-temperature airproof acid digestion for sample preparation were investigated. It is shown that the low-temperature airproof acid digestion method is of lower blank, and more suitalbe for the coal sample preparation. The on-line internal standard (Rh) sample introduction is applied to compensate matrix effects in measurement by ICPMS. The method gives low detection limits (0.002-1.60 μg/g) and better relative standard deviations (0.60%-4.78%) for the determined 49 elements in coal.
文摘A GC-MS method was established for determination of 10 pyrethroids in apple juice concentrate.The sample was extracted by acetone and hexane,and the 10 pyrethroids were separated on a capillary column(DB-5,30 m×250 μm×0.25 μm) and determined by GC-MSD.The recoveries of pyrethroids were range of 84%-96% with the detection limits of 3-46 μg/kg.The relative standard deviations were range of 0.68%-5.11%.
文摘A direct determination method for the atrazine residue on the vegetable was developed by using desorption electrospray ionization mass spectrometry (DESI MS) without any sample pretreatment.Acetonitrile-water (1:1,v/v),which contained 0.1% formic acid,was used as the spray solvent.The working conditions,such as ESI gas inlet pressure,ESI flow rate,ESI spray voltage,spray-to-sample distance,spray-to-cone-hole distance and the collision induced dissociation (CID) voltage for MS/MS,were optimized for both DESI and esquires 6 000 mass spectrometer.The linear range of atrazine on cabbage leaves was 25.25-2 525 pg/mm2,the R2 was 0.991 6,and the relative standard deviations were between 3.37% and 26.17%.The LOD of atrazine calculated by S/N=3 was 2.50 pg/mm2.
文摘A high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICPMS) was combined, and the chromatography conditions were optimized. The stability and homogeneity of a trimethyllead reference material were determined using this method.
文摘In human subjects,morphine is extensively metabolized to form(M3G)and morphine-6-glucuronide(M6G).This article established a sensitive LC-MS/MS method that allows the quantification of morphine and its glucuronide metabolites.
文摘A method for simultaneous determination of oxytetracycline,tetracycline,chlortetracycline in animal tissue was successfully established by HPLC-ESI MS/MS.The tetracycline antibiotics in animal tissue were extracted by liquid-solid extraction and cleaned up by SPE.The mass spectrometer was operated in the positive-ion mode using selected reaction monitoring(SRM).The results showed that three tetracycline antibiotics were well separated under the optimal conditions.The detection limits of oxytetracycline,tetracycline and chlortetracycline were 0.16 ng/g,0.1 ng/g and 0.1 ng/g,respectively.The spiked recoveries were range of 84%-94% and the relative standard deviations were 2.4%-2.9%.
文摘Background&Objective Tumor-associated macrophages(TAM)are induced by many cytokines,such as IL-4,IL-10,IL-13,and are considered to be of the M2 phenotype,which provides an immunosuppressive microenvironment for tumor growth.However,biomechanistssuggest that cells in the tumor microenvironment are affected not only by chemical signals but also mechanical factors,of which the stiffness of tissues is a major determinant.Compared with normal tissues,including the peri-tumor tissues,tumor tissues are more rigid.Heretofore,the influence,on the differentiation and function of macrophages,of the differences in such physical aspect between
文摘针对现有的作战需求表征与作战方案评价存在不确定性信息、作战方案设计中经验积累与重用以及作战方案推荐中相关性与多样性权衡问题,提出了一种不确定信息下考虑相关性与多样性的作战方案推荐方法。首先,将粗糙集理论融入最优最劣法(best-worst method,BWM)中对各作战能力属性进行赋权;其次,给出了不确定信息下作战方案与任务需求之间的相关性、作战方案之间的多样性计算模型;然后,提出了权衡相关性和多样性的行列式点过程(determinantal point process,DPP)模型,在此基础上,给出了贪婪最大后验概率(maximum a posterior,MAP)推断算法和贪婪Trade-off推断算法以获得作战方案最优推荐子集;最后,通过案例分析验证了所提模型和方法的适用性和可行性。
文摘A method for the simultaneous determination of β2-agonists residues was developed by LC-MS/MS.The results indicated that the calibration curves showed good linear range from 0.1 g/L to 10 g/L for 11 β2-agonists.The spiked recoveries were between 79% and 110%.The method was rapid,accurate,and was suitable for the determination of β2-agonists in animal food.
文摘针对大多数的图像自动标注结果中含有冗余标签、信息量不够丰富的问题,本文提出了一种基于级联网络和语义层次结构的图像自动标注方法(CNSH)。首先,输入数据集的图片和标签列表,采用级联的VGG网络提取图像特征,训练条件行列式点过程(DPP)算法模型,计算标签的质量分数确定候选标签列表;其次,利用WordNet检索数据集标签得到语义层次结构和同义词,进而构建加权语义路径;最后,利用DPP算法在候选标签集中采样,得到最终的标注结果。与传统的图像标注任务相比,本文方法得到的标注结果能准确描述图片内容,且不含冗余标签。许多评估指标已用于图像标注和多标签学习,但是它们只专注于评估代表性,忽略了多样性。为了解决上述问题,本文采用了基于语义层次结构的语义指标来共同评估代表性和多样性。在IAPRTC-12和ESP Game 2个基准数据集上的实验表明,与现有方法相比本文方法能够产生更具代表性和多样性的标签。
