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布莱克—斯科尔斯期权定价模型的研究

贵阳学院学报（自然科学版） 2010年第2期5卷 13-18页

作者：胡春生贵阳学院经济管理系贵州贵阳550005

期权的价格变化是一个随机过程,B—S模型的创立开创了以无套利原理为基础的现代金融理论的大规模发展,使金融实践产生了革命性的变化。B—S模型的开创性表现在三个方面——使用瞬间无风险的自我融资交易技术;用无套利方法,获得具有普遍... 详细信息

期权的价格变化是一个随机过程,B—S模型的创立开创了以无套利原理为基础的现代金融理论的大规模发展,使金融实践产生了革命性的变化。B—S模型的开创性表现在三个方面——使用瞬间无风险的自我融资交易技术;用无套利方法,获得具有普遍意义、不包含任何风险因素的B—S偏微分方程;诱发了对于公司金融和实际投资领域内问题的或有权益分析方法以及真实期权方法的深入研究和大量运用。分别利用随机偏微分方程方法和鞅方法,着重对B—S模型进行了证明。最后对B—S模型进行了评价。

关键词：布莱克-斯科尔斯模型期权定价鞅伊藤定理欧式看涨期权标准维纳过程

用于深海作业的激光陀螺高精度定位定向系统的仿真与实验

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热带海洋学报 2009年第4期28卷 22-27页

作者：胡春生秦石乔王省书黄宗升国防科学技术大学光电科学与工程学院湖南长沙410073 国防科学技术大学理学院湖南长沙410073

定位定向技术是深海作业系统的主要关键技术之一。本文基于激光陀螺提出了一种用于深海作业的高精度定位定向系统研究方案,建立了一套相应的系统分析方法,对该方案的姿态、速度、位置误差进行了详细的仿真分析。进行了72h静态定位定向实... 详细信息

定位定向技术是深海作业系统的主要关键技术之一。本文基于激光陀螺提出了一种用于深海作业的高精度定位定向系统研究方案,建立了一套相应的系统分析方法,对该方案的姿态、速度、位置误差进行了详细的仿真分析。进行了72h静态定位定向实验,结果表明系统的俯仰角和横滚角误差小于0.006°,航向角误差小于0.035°,速度误差小于0.9m·s-1,定位误差小于29.9km。实验结果与仿真分析结果基本一致,验证了该研究方案的可行性。和采用动力调谐陀螺的定位定向系统相比,本系统具有精度高和可靠性好等优点。

关键词：定位定向深海作业激光陀螺加速度计

Chinese herbal medicine decreases incidence of hepatocellular carcinoma in diabetes mellitus patients with regular insulin management

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 716-731页

作者： Hsiang-chun Lai Ju-Chien Cheng Hei-Tung Yip Long-Bin Jeng sheng-Teng huang Graduate Institute of Chinese Medicine School of Chinese MedicineCollege of Chinese MedicineChina Medical UniversityTaichung 404328TaiwanChina Department of Medical Laboratory Science and Biotechnology China Medical UniversityTaichung 404TaiwanChina Management Office for Health Data China Medical University HospitalTaichung 404327TaiwanChina Organ Transplantation Center China Medical University HospitalTaichung 40447TaiwanChina Department of Chinese Medicine China Medical University HospitalSchool of Chinese MedicineChina Medical UniversityTaichung 40447TaiwanChina

BACKGROUND Type 2 diabetes mellitus(DM)is an independent risk factor for hepatocellular carcinoma(HCC),while insulin is a potent *** a new therapeutic modality for preventing insulin users from developing HCC is a critical goal for *** To investigate whether regular herbal medicine use can decrease HCC risk in DM patients with regular insulin *** We used data acquired from the Taiwan,Chinaese National Health Insurance research database between 2000 and *** identified patients with DM who were prescribed insulin for>3 *** herb user group was further defined as patients prescribed herbal medication for DM for>3 months per annum during RESULTS We initially enrolled 657144 DM patients with regular insulin use from 2000 to *** these,46849 patients had used a herbal treatment for DM,and 140547 patients were included as the matched control *** baseline variables were similar between the herb users and *** patients with regular herb use had a 12%decreased risk of HCC compared with the control group[adjusted hazard ratio(aHR)=0.88,95%CI=0.80–0.97].The cumulative incidence of HCC in the herb users was significantly lower than that of the *** with a herb use of>5 years cumulatively exhibited a protective effect against development of HCC(aHR=0.82,Phuang Qi)plus Salvia miltiorrhiza Bunge(Dan Shen),and Astragalus propinquus(huang Qi)plus Trichosanthes kirilowii Maxim.(Tian hua Fen)were the most frequent combination of single ***,Ji sheng Shen Qi Wan plus Dan Shen was the most frequent combination of herbs and *** This large-scale retrospective cohort study reveals th

关键词： Hepatocellular carcinoma Diabetes mellitus Insulin Herb Taiwan,Chinaese National health insurance research database

Better use of experience from other reservoirs for accurate production forecasting by learn-to-learn method

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Petroleum Science 2024年第1期21卷 716-728页

作者： Hao-Chen Wang Kai Zhang Nancy Chen Wen-sheng Zhou Chen Liu Ji-Fu Wang Li-Ming Zhang Zhi-Gang Yu Shi-Ti Cui Mei-chun Yang China University of Petroleum(East China) 66 Changjiang West RoadQingdao West Coast New AreaQingdao266580ShandongChina University of Calgary 2500 University Dr NWCalgaryT2N 1N4AlbertaCanada Qingdao University of Technology Qingdao266071ShandongChina State Key Laboratory of Offshore Oil Exploitation Beijing100028China CNOOC Research Institute Ltd. Beijing100028China CNPC Tarim Oilfield Branch Company Korla841000XinjiangChina National Engineering Laboratory for Exploration and Development of Low-Permeability Oil and Gas Fields Xi'an710000ShaanxiChina Sinopec Matrix Co. LTDQingdao266000ShandongChina

To assess whether a development strategy will be profitable enough,production forecasting is a crucial and difficult step in the *** development history of other reservoirs in the same class tends to be studied to make predictions ***,the permeability field,well patterns,and development regime must all be similar for two reservoirs to be considered in the same *** results in very few available experiences from other reservoirs even though there is a lot of historical information on numerous reservoirs because it is difficult to find such similar *** paper proposes a learn-to-learn method,which can better utilize a vast amount of historical data from various ***,the proposed method first learns how to learn samples before directly learning rules in ***,by utilizing gradients from networks with independent parameters and copied structure in each class of reservoirs,the proposed network obtains the optimal shared initial parameters which are regarded as transferable information across different *** on that,the network is able to predict future production indices for the target reservoir by only training with very limited samples collected from reservoirs in the same *** cases further demonstrate its superiority in accuracy to other widely-used network methods.

关键词： Production forecasting Multiple patterns Few-shot learning Transfer learning

Whole-volume histogram analysis of spectral-computed tomography iodine maps characterizes HER2 expression in gastric cancer

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World Journal of Gastroenterology 2024年第38期30卷 4211-4220页

作者： Wei-Ling Zhang Jing Sun Rong-Fang huang Yi Zeng Shu Chen Xiao-Peng Wang Jin-hu Chen Yun-Bin Chen chun-Su Zhu Zai-sheng Ye You-Ping Xiao Department of Radiology Clinical Oncology School of Fujian Medical University&Fujian Cancer Hospital(Fujian Branch of Fudan University Affiliated Cancer Hospital)Fuzhou 350014Fujian ProvinceChina Department of Pathology Clinical Oncology School of Fujian Medical University&Fujian Cancer Hospital(Fujian Branch of Fudan University Affiliated Cancer Hospital)Fuzhou 350014Fujian ProvinceChina Department of Gastric Surgery Clinical Oncology School of Fujian Medical University&Fujian Cancer Hospital(Fujian Branch of Fudan University Affiliated Cancer Hospital)Fuzhou 350014Fujian ProvinceChina Department of Epidemiology Clinical Oncology School of Fujian Medical University&Fujian Cancer Hospital(Fujian Branch of Fudan University Affiliated Cancer Hospital)Fuzhou 350014Fujian ProvinceChina

BACKGROUND Although surgery remains the primary treatment for gastric cancer(GC),the identification of effective alternative treatments for individuals for whom surgery is unsuitable holds ***2 overexpression occurs in approximately 15%-20%of advanced GC cases,directly affecting treatment-related ***-computed tomography(sCT)enables the quantification of material compositions,and sCT iodine concentration parameters have been demonstrated to be useful for the diagnosis of GC and prediction of its invasion depth,angioge-nesis,and response to systemic *** existing report describes the prediction of GC HER2 status through histogram analysis based on sCT iodine maps(IMs).AIM To investigate whether whole-volume histogram analysis of sCT IMs enables the prediction of the GC HER2 *** This study was performed with data from 101 patients with pathologically confirmed GC who underwent preoperative sCT *** parameters were extracted via sCT IM histogram analysis:The minimum,maximum,mean,standard deviation,variance,coefficient of variation,skewness,kurtosis,entropy,percentiles(1st,5th,10th,25th,50th,75th,90th,95th,and 99th),and lesion *** correlations of the parameters with the HER2 status and clinicopathological parameters were *** operating characteristic curves were used to evaluate the parameters’diagnostic *** Values for the histogram parameters of the maximum,mean,standard deviation,variance,entropy,and percentiles were significantly lower in the HER2+group than in the HER2–group(all P<0.05).The GC differentiation and Lauren classification correlated significantly with the HER2 status of tumor tissue(P=0.001 and 0.023,respectively).The 99th percentile had the largest area under the curve for GC HER2 status identification(0.740),with 76.2%,sensitivity,65.0%specificity,and 67.3%*** sCT IM histogram parameters correlated positively with the GC HER2 status(r=0.

关键词： Gastric cancer Spectral computed tomography Iodine map Histogram analysis

基因治疗用质粒DNA生产面临的问题及研究进展

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中国生物工程杂志 2011年第4期31卷 119-123页

作者：胡春生张庆林张通军事医学科学院放射与辐射医学研究所北京100850 内蒙古工业大学化工学院呼和浩特010051

基因治疗已成为21世纪一些重大疾病的有效治疗策略,目前携带治疗基因的重组质粒已作为基因药物进入临床研究。对用于基因治疗的生物制品的生产与质量控制都有相当严格的要求。虽然已建立大规模符合药学规格的质粒DNA生产工艺,能满足临... 详细信息

基因治疗已成为21世纪一些重大疾病的有效治疗策略,目前携带治疗基因的重组质粒已作为基因药物进入临床研究。对用于基因治疗的生物制品的生产与质量控制都有相当严格的要求。虽然已建立大规模符合药学规格的质粒DNA生产工艺,能满足临床需求,但在这些生产工艺中还存在一些难以克服的瓶颈,如:载体构建、细胞裂解、细菌染色体DNA去除、细菌内毒素去除、生产过程中质量控制等。就近年来大规模生产临床用质粒DNA遇到的相关问题及解决方案作一综述。

关键词：基因治疗质粒DNA 大规模碱裂解纯化

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喷灌条件下不同灌水处理冬小麦的叶水势特征

土壤 2005年第4期37卷 410-414页

作者：高鹭胡春胜陈素英中国科学院地理科学与资源研究所中国科学院遗传与发育生物学研究所石家庄050021

在喷灌区一季冬小麦的试验表明,冬小麦叶水势值在各生育期每天的1400左右发生明显变化;从生育期看,返青期叶水势低谷值出现较晚,持续时间短且恢复较快;孕穗和开花期低谷出现有提前和持续时间延长趋势;叶水势不完全随生育进程与土壤水分... 详细信息

在喷灌区一季冬小麦的试验表明,冬小麦叶水势值在各生育期每天的1400左右发生明显变化;从生育期看,返青期叶水势低谷值出现较晚,持续时间短且恢复较快;孕穗和开花期低谷出现有提前和持续时间延长趋势;叶水势不完全随生育进程与土壤水分同步变化,原因为同一时期内土壤水分是造成叶水势差异的主导因素,但同时外界条件的变化也对叶水势的变化有一定的影响作用。前期叶水势在黎明前和中午都与浅层土壤水分关系密切;到开花和灌浆期叶水势则变为只在中午与浅层土壤水分关系密切,黎明前更多依赖深层土壤水分状况,表现为与深层土壤水分关系密切。喷灌条件下,当返青后灌水量超过150mm时,灌水量对叶水势的影响减小。

关键词：喷灌冬小麦叶水势土壤含水量

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喷灌条件下冬小麦冠层温度的试验研究

干旱地区农业研究 2005年第2期23卷 1-5页

作者：高鹭陈素英胡春胜中国科学院地理科学与资源研究所中国科学院遗传与发育生物学研究所河北石家庄050021

研究了喷灌条件下冬小麦冠层温度在不同土壤水分条件下的变化规律及其随作物生长发育期的变化状况。结果表明,在喷灌条件下,冠层温度的变化规律同普通灌溉的变化规律基本相同。当灌水量达一定程度后,冠层温度不再下降,反而呈现上升趋势... 详细信息

研究了喷灌条件下冬小麦冠层温度在不同土壤水分条件下的变化规律及其随作物生长发育期的变化状况。结果表明,在喷灌条件下,冠层温度的变化规律同普通灌溉的变化规律基本相同。当灌水量达一定程度后,冠层温度不再下降,反而呈现上升趋势;土壤水分对冠层温度的影响程度相对减小,不为主要决定因子;对于冬小麦,当灌溉量增加到一定程度时,反而不利于冬小麦的生长,水分利用效率也下降,在灌足底墒水和返青、拔节期均灌溉的情况下,小麦生长期间每次灌水量不宜过大,以每次灌水量不超过300m3/hm2为宜。

关键词：冠层温度冬小麦喷灌灌水量土壤水分灌溉量作物生长发育条件下降增加

喷灌条件下冬小麦根系分布与土壤水分条件的关系

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华南农业大学学报 2006年第1期27卷 5-8页

作者：高鹭胡春胜陈素英中国科学院遗传与发育生物学研究所河北石家庄050021

根据喷灌水分在土壤中的分布特点,研究了不同灌水定额下冬小麦根系生长规律和分布状况.结果表明:同地面灌相比,喷灌条件下作物根系相对集中于表层,有上移现象,喷灌更适合作物生长需要,可提高水分的利用率;根长密度不论是在拔节期还是在... 详细信息

根据喷灌水分在土壤中的分布特点,研究了不同灌水定额下冬小麦根系生长规律和分布状况.结果表明:同地面灌相比,喷灌条件下作物根系相对集中于表层,有上移现象,喷灌更适合作物生长需要,可提高水分的利用率;根长密度不论是在拔节期还是在收获时其最大值总是在20 cm深度,在剖面上的垂直分布随深度增加而递减;不同灌水处理下根系的衰亡速率出现差异,灌水量大根系的衰亡速率较小,在灌水总量相近的情况下,表层能较长时间保持湿润的处理,其根系衰亡速率要小,总体根系的衰亡主要表现为表层根系的衰亡;在该试验的3个灌溉水平下,小麦拔节期和收获时各处理不同层次的根干质量无显著性差异.

关键词：喷灌冬小麦根系生长根系分布