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一种新的拟合地震动衰减关系的分步回归法 被引量:13
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作者 肖亮 俞言祥 《地震学报》 CSCD 北大核心 2010年第6期725-732,共8页
提出了拟合地震动衰减关系的一种新的分步回归法.该方法首先确定近场饱和项,再获得距离衰减项,最后确定震级项.作为算例,采用NGA项目美国西部地区的强震观测资料,对基岩场地自由地表加速度反应谱平台高度值衰减关系进行了回归.结果表明... 提出了拟合地震动衰减关系的一种新的分步回归法.该方法首先确定近场饱和项,再获得距离衰减项,最后确定震级项.作为算例,采用NGA项目美国西部地区的强震观测资料,对基岩场地自由地表加速度反应谱平台高度值衰减关系进行了回归.结果表明,采用此方法对实际资料的拟合不存在系统偏差,结果稳定,能反映强震地震动在近场的距离饱和与震级饱和特性.对远场数据考虑截尾效应,能使回归结果正确反映地震动的远场衰减特征. 展开更多
关键词 衰减关系 地震动 分步回归 近场饱和 截尾效应
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基于分步回归策略的霍脱尔气体发射率数学模型 被引量:1
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作者 童长仁 吴金财 +1 位作者 李明周 刘道斌 《冶金能源》 北大核心 2008年第1期23-25,61,共4页
针对冶金炉窑燃烧释热场、温度场计算机仿真过程中气体发射率的动态计算问题,采用计算机图形处理技术从霍脱尔发射率曲线图中智能提取数据,并基于分步回归策略,建立了CO2、SO2、H2O等气体的发射率数学模型。模型检验和误差分析表明,该... 针对冶金炉窑燃烧释热场、温度场计算机仿真过程中气体发射率的动态计算问题,采用计算机图形处理技术从霍脱尔发射率曲线图中智能提取数据,并基于分步回归策略,建立了CO2、SO2、H2O等气体的发射率数学模型。模型检验和误差分析表明,该模型回归结果误差小,满足辐射换热工程计算精度要求。 展开更多
关键词 气体发射率 霍脱尔曲线 辐射换热 温度场仿真 分步回归
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论我国外汇储备规模的影响因素——基于分步回归法的实证分析 被引量:3
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作者 武晋 《福建金融》 2013年第1期49-51,共3页
加入WTO后,我国外汇储备余额持续快速增长,迄今已稳居世界第一位,反映出我国国际支付能力空前宽裕。然而外汇储备规模过大,会造成外汇资源的闲置浪费以及国内货币供给的过快,冲击宏观经济稳定。本文运用多元线性模型的分步回归法,对我... 加入WTO后,我国外汇储备余额持续快速增长,迄今已稳居世界第一位,反映出我国国际支付能力空前宽裕。然而外汇储备规模过大,会造成外汇资源的闲置浪费以及国内货币供给的过快,冲击宏观经济稳定。本文运用多元线性模型的分步回归法,对我国外汇储备规模的影响因素进行实证分析,进而提出实行外汇储备适度规模管理的政策建议。 展开更多
关键词 外汇储备 分步回归 影响因素 实证分析
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煤矿企业安全人力资本开发对安全绩效影响的实证研究 被引量:8
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作者 刘良灿 李鲁林 +1 位作者 王邦兆 张同建 《贵州师范大学学报(社会科学版)》 2020年第5期82-91,共10页
安全是煤矿生产的核心。我国煤矿行业的事故率较高,是阻碍煤矿生产率提高的重要因素。安全人力资本开发是煤矿企业安全管理的关键。安全人力资本开发包括多种行为要素。基于我国煤矿企业的样本数据,借助于分步回归分析法,基于安全绩效... 安全是煤矿生产的核心。我国煤矿行业的事故率较高,是阻碍煤矿生产率提高的重要因素。安全人力资本开发是煤矿企业安全管理的关键。安全人力资本开发包括多种行为要素。基于我国煤矿企业的样本数据,借助于分步回归分析法,基于安全绩效改进的目标,经验性的研究发现,安全文化培育和安全技能改进发挥了较大的作用。安全资金投入、安全经验推广、安全素质开发发挥了一般性的作用。而强化安全意识、安全培训质量、安全心理疏导没有发挥相应的作用。研究结论为我国煤矿企业安全人力资本的开发提供了现实性的理论借鉴。 展开更多
关键词 煤矿企业 安全人力资本 安全文化 安全心理疏导 分步回归分析
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阿里亚斯强度衰减关系分析 被引量:8
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作者 李伟 俞言祥 肖亮 《地震学报》 CSCD 北大核心 2017年第6期921-929,共9页
本文选取美国NGA强震数据库中与我国大陆构造环境相近的美国西部、中亚和我国台湾地区的自由地表强震记录,计算其水平向阿里亚斯强度;采用分步回归法依次求取近场饱和项、距离衰减项、震级项、断层类型项和场地类别项的系数,得出衰减模... 本文选取美国NGA强震数据库中与我国大陆构造环境相近的美国西部、中亚和我国台湾地区的自由地表强震记录,计算其水平向阿里亚斯强度;采用分步回归法依次求取近场饱和项、距离衰减项、震级项、断层类型项和场地类别项的系数,得出衰减模型,并基于回归结果与实际数据的对比,分析了残差随距离或震级的分布.与前人工作得出的全球活动板块边界、新西兰和我国台湾地区的3种阿里亚斯强度衰减模型进行的比较显示,在MW6.5或远场区域4种模型的结果较接近,近场区域在高震级和低震级时有一定差异.最后,选取2008年汶川M W7.9和2013年芦山M W6.8两次地震的强震记录对模型进行检验,结果显示本文衰减关系均与实际数据拟合得很好,表明本文的模型适用于我国大陆地区的相关研究. 展开更多
关键词 阿里亚斯强度 衰减关系 分步回归 震级饱和 距离饱和
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Variation characteristics of stable isotopes in atmospheric precipitation in Adelaide,Australia
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作者 WANG Dizhou ZHANG Xinping +2 位作者 LIU Zhongli LI Guang GUAN Huade 《地球环境学报》 CSCD 2024年第4期641-652,共12页
Background,aim,and scope Stable isotope in water could respond sensitively to the variation of environment and be reserved in different geological archives,although they are scarce in the environment.And the methods d... Background,aim,and scope Stable isotope in water could respond sensitively to the variation of environment and be reserved in different geological archives,although they are scarce in the environment.And the methods derived from the stable isotope composition of water have been widely applied in researches on hydrometeorology,weather diagnosis,and paleoclimate reconstruction,which help well for understanding the water-cycle processes in one region.Here,it is aimed to explore the temporal changes of stable isotopes in precipitation from Adelaide,Australia and determine the influencing factors at different timescales.Materials and methods Based on the isotopic data of daily precipitation over four years collected in Adelaide,Australia,the variation characteristics of dailyδD,δ^(18)O,and dexcess in precipitation and its relationship with meteorological elements were analyzed.Results The results demonstrated the local meteoric water line(LMWL)in Adelaide,wasδD=6.38×δ^(18)O+6.68,with a gradient less than 8.There is a significant negative correlation between dailyδ^(18)O and precipitation amount or relative humidity at daily timescales in both the whole year and wither/summerhalf year(p<0.001),but a significant positive correlation between dailyδ^(18)O and temperature in the whole year and the winter half-year(p<0.001).Discussion The correlation coefficients betweenδ^(18)O and daily mean temperature didn’t show a significant positive correlation,which may be attributed to that the precipitation in Adelaide area in January was mainly influenced by strong convective weather,and the stable isotope values in precipitation were significantly negative.Furthermore,this propose was also evidenced by the results from dexcess of precipitation with larger value in the winter half-year than that in the summer half-year,which may be resulted from the precipitation events in winter are mostly influenced by oceanic water vapor,while the sources of water vapor in summer precipitation events are more complicated and influenced by strong convective weather.On the other hand,the slope and intercept of theδ^(18)O—P regression lines in the summer months(-0.41 and 0.50‰)are larger and smaller than those in the winter months(-0.22 and-2.15‰),respectively,indicating that the precipitation stable isotopes have a relatively stronger rainout effect in the summer months than in the winter months.Besides,the measured values ofδ^(18)O in daily precipitation have a good linear relationship with our simulated values ofδ^(18)O,demonstrating the established regression model could provide a reliable simulation for theδ^(18)O values in daily precipitation in Adelaide area.It’s worth noting that the precipitation events with low precipitation amount,low relative humidity and high temperature,usually had relatively small slope and intercept of MWL,implying that raindrops may be strongly affected by sub-cloud secondary evaporation in the falling process.Conclusions The variation ofδ^(18)O in daily precipitation from Adelaide region was controlled by different factors at different timescales.And the water vapor sources and the meteorological conditions of precipitation events(such as the degree of sub-cloud secondary evaporation)also played an important role on the variation ofδ^(18)O.Recommendations and perspectives Stable isotope in daily precipitation can provide more accurate information about water-cycle and atmosphere circulation,it is therefore necessary to continue to collect and analyze daily-scale precipitation data over a longer time span.The results of this study will provide the basis for the fields of hydrometeorology,meteorological diagnosis and paleoclimate reconstruction in Adelaide,Australia. 展开更多
关键词 Adelaide PRECIPITATION stable isotopes meteoric water line stepwise regression analysis
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Application of cluster analysis and stepwise regression in predicting the traffic volume of lanes 被引量:5
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作者 张赫 王炜 顾怀中 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期359-362,共4页
Because of the difficulty to obtain the traffic flow information of lanes at non-detector intersections in most metropolises of the world,based on the relationships between the lanes of signal-controlled intersections... Because of the difficulty to obtain the traffic flow information of lanes at non-detector intersections in most metropolises of the world,based on the relationships between the lanes of signal-controlled intersections,cluster analysis and stepwise regression are integrated to predict the traffic volume of lanes at non-detector isolated controlled intersections.First cluster analysis is used to cluster the lanes of non-detector isolated signal-controlled intersections and the lanes of all signal-controlled intersections with detectors.Then, by the results of cluster analysis,the traffic volume samples are selected randomly and stepwise regression is used to predict the traffic volume of lanes at non-detector isolated signal-controlled intersections.The method is tested by the traffic volume data of lanes of the road network of Nanjing city.The problem of predicting the traffic volume of lanes at non-detector isolated signal-controlled intersections was resolved and can be widely used in urban traffic flow guidance and urban traffic control in cities without enough intersections equipped with detectors. 展开更多
关键词 intelligent transportation systems (ITS) cluster analysis stepwise regression
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我国本土技术创新对工业TFP的影响研究
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作者 常春梅 姚笑秋 刘信 《全球科技经济瞭望》 2020年第12期12-21,共10页
本文通过Malmquist TFP指数测算分析我国工业2008—2017年TFP指数技术效率、技术进步,通过分步回归计量模型研究了我国本土技术创新对工业技术进步的影响。结果显示,我国TFP指数的进步源自技术进步的影响;我国本土技术创新投入对工业技... 本文通过Malmquist TFP指数测算分析我国工业2008—2017年TFP指数技术效率、技术进步,通过分步回归计量模型研究了我国本土技术创新对工业技术进步的影响。结果显示,我国TFP指数的进步源自技术进步的影响;我国本土技术创新投入对工业技术进步的影响程度仅为2.6%。我国工业仍处于吸收模仿的中低端水平,并未充分利用已有资源进行自主科技创新。 展开更多
关键词 工业TFP 技术进步 技术创新 分步回归
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后金融危机下我国企业“走出去”的挑战与对策分析 被引量:1
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作者 武晋 《金融经济(下半月)》 2013年第1期29-30,共2页
自2008年金融海啸的全球蔓延,西方发达国家经济受到严重冲击,以中国为代表的新兴市场国家面临空前复杂的外部环境,金融危机造成世界范围内的资产价格重估,发达经济体的资产价格泡沫受到了充分的挤压,与此同时,金融危机后的国际市场发展... 自2008年金融海啸的全球蔓延,西方发达国家经济受到严重冲击,以中国为代表的新兴市场国家面临空前复杂的外部环境,金融危机造成世界范围内的资产价格重估,发达经济体的资产价格泡沫受到了充分的挤压,与此同时,金融危机后的国际市场发展前景仍然并不明朗。本文就后金融危机下的复杂形势,针对当前中资企业"走出去"的机遇和挑战展开分析,并提出支持中资企业"走出去"的政策建议。 展开更多
关键词 外汇储备 分步回归 影响因素 实证分析
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Relationship between Rice Planthopper Occurrence Area in China and Atmospheric Circulation Indices 被引量:3
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作者 季璐 朱敏 《Agricultural Science & Technology》 CAS 2012年第9期2006-2011,共6页
[Objective] This study aimed to establish models based on atmospheric cir- culation indices for forecasting the area attacked by rice planthopper every year, and to provide guide for preventing and controlling plantho... [Objective] This study aimed to establish models based on atmospheric cir- culation indices for forecasting the area attacked by rice planthopper every year, and to provide guide for preventing and controlling planthopper damage. [Method] The data related to rice planthopper occurrence and atmospheric circulation were collected and analyzed with the method of stepwise regression to establish the prediction models. [Result] The factors significantly related to the area attacked by rice plan-thopper were selected. Two types of prediction models were established. One was for Sogatella furcifera (Horvath), based on Atlantic-Europe circulation pattern W in October in that year, Pacific polar vortex area index in October in that year, North America subtropical high index in August in that year, Atlantic-Europe circulation pattern W in June in that year, northern boundary of North America subtropical high in February in that year, Atlantic-Europe polar vortex intensity index in October in that year and Asia polar vortex intensity index in November in the last year; the other type of prediction models were for Nilaparvata lugens (Stal), based on the Eastern Pacific subtropical high intensity index in July in that year, northern hemi- sphere polar vortex area index in October in the last year, Asia polar vortex strength index in November in the last year, north boundary of North America-At- lantic subtropical high in September in that year, north boundary of North Africa-At- lantic-North America subtropical high in January in that year, sunspot in September of the last year and eastern Pacific subtropical high area index in September in that year. [Conclusion] With the stepwise regression, the forecasting equations of the rice planthopper occurrence established based on the atmospheric circulation indices could be used for actual forecast. 展开更多
关键词 Rice planthopper Atmospheric circulation Prediction models
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Physiological Changes during the Process of Pericarp Browning in the Postharvest Litchi 被引量:9
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作者 王家保 王向社 +1 位作者 徐碧玉 金志强 《Agricultural Science & Technology》 CAS 2010年第5期10-16,共7页
[Objective] Pericarp browning in the postharvest litchi significantly reduced its commercial value and limited the expanding of litchi markets. Physiological changes during the process of pericarp browning were determ... [Objective] Pericarp browning in the postharvest litchi significantly reduced its commercial value and limited the expanding of litchi markets. Physiological changes during the process of pericarp browning were determined in order to identify the underlying mechanisms. [Method] Matured Feizixiao fruits were stored at 25 ℃ and 70%±5% relative humidity. The physiological changes happened in pericarp during storage were tested at an 8-hour interval. [Result] The fruit of Feizixiao (Litchi chinensis Sonn. cv Feizixiao) turned completely brown within 72 h after being harvested under the experimental conditions. Sharp increase of the browning index occurred from 48 to 64 hours after harvest (HAH). With the browning of pericarp,water content of the whole fruit and pericarp decreased continuingly. In contrast,there were no significant changes in the water content of pulp during the same period. MDA content,pH value and relative leakage rate of pericarp were increased during storage. Most of pigment contents including anthocyanin,flavonoid,phenols,chlorophyll a and total chlorophyll decreased. POD activity was initially increased in 32 HAH and then decreased afterwards. PPO activity was decreased continuously,while the activities of catalase and superoxide dismutase exhibited the pattern of 'increasing-decreasing-increasing' as the storage time progressed. Correlation,stepwise regression and path analyses showed that water loss of pericarp was the major factor of pericarp browning. Principal and cluster analyses showed that there were two stages of pericarp browning during the course of litchi storage. [Conclusion] Water status of pericarp was the most important factor affecting pericarp browning. The pericarp browning happened by stages,which was mainly determined by the water loss of pericarp. 展开更多
关键词 Litchi (Litchi chinensis Sonn.) Pericarp browning Physiological changes Principal analysis:Cluster analysis
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Correlation and path analysis of morphological and weight traits in marine gastropod Glossaulax reiniana 被引量:11
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作者 赵力强 何阳阳 +2 位作者 杨凤 聂鸿涛 闫喜武 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第4期821-827,共7页
Using correlation and path analysis, the genetic correlation between weight traits and morphological traits was determined in the marine gastropod Glossaulax reiniana. A total of 100 G. reiniana individuals from a wil... Using correlation and path analysis, the genetic correlation between weight traits and morphological traits was determined in the marine gastropod Glossaulax reiniana. A total of 100 G. reiniana individuals from a wild population were used. Shell width (X1), shell height (X2), umbo-callus height (X3), body width (X4), operculum length (X5), operculum width (X6), body weight (Y1) and soft-tissue weight (Y2) were measured, and the correlation coefficient matrix calculated. Morphological traits were used as independent variables and weight traits as dependent variables for path coefficient analysis. Path coefficients, correlation indices and determination coefficients were also determined. Results indicate that the correlation coefficients associated with each morphological and weight trait were all highly significant (P〈0.01). After deleting redundant independent variables, the following optimum multiple regression equations were obtained using stepwise multiple regression analysis: Y1=-29.317+0.362X2+0.349X4+ 1.190)(5 for body weight; and Y2=-17.292+0.166X1+0.171X2+0.703X5, for soft-tissue weight. Operculum height had the highest positive direct correlation with both body weight and soft-tissue weight, which was in accordance with the test results obtained from determinate coefficient analysis. The indication of high genetic correlations between weight traits and morphological traits will provide valuable information for G. reiniana breeding programs. 展开更多
关键词 Glossaulax reiniana correlation and path analysis morphological traits weight traits
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Association of glomerular filtration rate with arterial stiffness in Chinese women with normal to mildly impaired renal function 被引量:4
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作者 Su-Yan Bian Hong-Yang Guo +6 位作者 Ping Ye Lei-Ming Luo Hong-Mei Wu Wen-Kai Xiao Li-PingQi He-Peng Yu Liu-Fa Duan 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2012年第2期158-165,共8页
Objective Both decreased glomemlar filtration rate (GFR) and arterial stiffness were considered as risk factors for atherosclerosis. Previous studies have suggested the association between central arterial stiffness... Objective Both decreased glomemlar filtration rate (GFR) and arterial stiffness were considered as risk factors for atherosclerosis. Previous studies have suggested the association between central arterial stiffness and the degree of GFR loss. Whether decreased GFR contributes to peripheral artery stiffness remains controversial. Moreover, data analyzed from a cohort of Chinese women are rare. Our aim was to explore the relationship between GFR and regional arterial stiffness in Chinese women. Methods In this cross-sectional study, we randomly recruited 1131 adult women residents with GFR 〉 60 mL/min per 1.73 m2 estimated by the Chinese Modification of Diet in Renal Disease equation from three large communities. Central and peripheral arterial stiffness were estimated simultaneously by measuring carotid-femoral pulse wave velocity (PWVcf) and carotid-radial PWV (PWVcr) using a validated automatic device. Augmentation Index at heart rate 75 beats/minutes (AIx-75) was measured by pulse wave analysis as a composite parameter reflecting both large and distal arterial properties. Results The mean estimated GFR (eGFR) of the study group was 100.05 + 23.26 mL/minute per 1.73 m2. Subjects were grouped by tertiles of eGFR level. PWVef and AIx-75 increased ongoing from the top to the bottom eGFR tertile, while the values of PWVcr were comparable. Both univariate Pearson correlations and multiple stepwise regression analyses showed that eGFR significantly correlated to PWVcf, but not to PWVcr and AJx-75. Conclusions In Chinese women with normal to mildly impaired renal function, decreased eGFR affected carotid-to-femoral rather than carotid-to-radial stiffening. This provides rational to conduct future prospective studies to investigate predictors of atherosclerosis in this population. 展开更多
关键词 Arterial stiffness Augmentation index Pulse wave velocity Glomerular filtration rate Chinese women
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A rabbit model of pediatric nonalcoholic steatohepatitis: The role of adiponectin 被引量:10
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作者 Jun-Fen Fu Yan-Lan Fang Li Liang Chun-Lin Wang Fang Hong Guan-Ping Dong 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第8期912-918,共7页
AIM: To create a rabbit model of pediatric nonalcoholic steatohepatitis (NASH) and to evaluate the role of adiponectin in the process. METHODS: Thirty-two specific pathogen-free male New Zealand rabbits were divid... AIM: To create a rabbit model of pediatric nonalcoholic steatohepatitis (NASH) and to evaluate the role of adiponectin in the process. METHODS: Thirty-two specific pathogen-free male New Zealand rabbits were divided randomly into three groups: (1) the normal control group (n = 10) was fed with standard diet for 12 wk; (2) the model group A (n = 11); and (3) model group B (n = 11) were fed with a highfat diet (standard diet + 10% lard + 2% cholesterol) for 8 and 12 wk, respectively. Hepatic histological changes were observed and biochemical parameters as well as serum levels of adiponectin, interleukin (IL)-6, IL-10 and tumor necrosis factor (TNF)-α were measured. RESULTS: Typical histological hepatic lesions of NASH were observed in both model groups described as liver steatosis, liver inflammatory infiltration, cytologic ballooning, perisinusoidal fibrosis and overall fibrosis. Compared with the normal control group, there were significant increases in model groups A and B in weight gain (1097.2 ± 72.3, 1360.5± 107.6 vs 928.0 ±58.1, P 〈 0.05, P 〈 0.01), liver weight (93.81±6.64, 104.6±4.42 vs 54.4±1.71, P 〈 0.01), Lg (ALT) (1.9±0.29, 1.84± 0.28 vs 1.60±0.17, P 〈 0.01), and Lg (TG) (1.03 ±0.24, 1.16 ±0.33 vs 0.00 ±0.16, P 〈 0.01). Weight gain was much more in model group B than in model group A (1360.5± 107.6 vs 1097.2 ±72.3, P 〈 0.05). But, there was no significant difference between the two groups concerning the other indexes. Pro-inflammatory cytokines (IL-6 and TNF-α) increased in model group B compared with that of control and model group A (IL-6:1.86±0.21 vs 1.41 ±0.33, 1.38± 0.42, P 〈 0.01; TNF-α: 1.18±0.07 vs 0.66 ±0.08, 0.86 ±0.43, P 〈 0.01, P 〈 0.05), whereas serum adiponectin and IL-10 decreased in model groups compared with that in the control (adiponectin: A: 21.87±4.84 and B: 21.48 ±4.60 vs 27.36 ±7.29, P 〈 0.05. IL-10: A: 1.72± 0.38 and B: 1.83 ±0.39 vs 2.26±0.24, P 〈 0.01). Lg (TC) and the degree of liver fatty infiltration was an independent determinant of serum adiponectin level analyzed by stepwise multiple regressions, resulting in 29.4% of variances. CONCLUSION: This rabbit model produces the key features of pediatric NASH and may provide a realistic model for future studies. Adiponectin level partially reflects the severity of liver steatosis, but not the degree of liver inflammation. 展开更多
关键词 Nonalcoholic steatohepatitis Pediatricanimal model ADIPONECTIN Interleukin 6 Tumornecrosis factor
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Psychological evaluation of patients after breast cancer surgery and care strategies improvement 被引量:1
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作者 Yanjun Zhang Caigang Liu Feng Jin 《The Chinese-German Journal of Clinical Oncology》 CAS 2011年第10期584-587,共4页
Objective: The aim of the study was to investigate the level of self-image of patients after breast cancer surgery, and explore factors influencing self-image among patients who have experienced different types of sur... Objective: The aim of the study was to investigate the level of self-image of patients after breast cancer surgery, and explore factors influencing self-image among patients who have experienced different types of surgeries, and set out a foundation for the improvement of care strategies. Methods: The 538 patients with primary breast cancer who underwent surgery in the Department of Breast Surgery, First Hospital of China Medical University, Shenyang, China, from January 2004 to January 2009 were included in the study. The psychological status of the patients was evaluated by body image after breast cancer questionnaire (BIBCQ), social support rating scale (SSRS), self-rating anxiety scale (SRAS), depression rating scale (DRS), and general information questionnaire. The factors influencing the self-image were selected by a stepwise regression analysis. Results: The patients who underwent breast-conserving surgery were the most satisfied with their body image, followed by those underwent surgery of modified radical mastectomy with reconstruction. However, cases treated by modified radical mastectomy without reconstruction had negative outcomes. Regardless of operation type, the self-image was influenced by anxiety, level of abuse by husband, and sexual satisfaction after operation. Conclusion: The self-image of patients who underwent different breast cancer surgeries was influenced by different factors, and individualized nursing should be offered in accordance with the specific situation. 展开更多
关键词 breast cancer operation NURSING SELF-IMAGE ANXIETY influencing factors
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Distribution and Abundance of Pelagic Tunicates in the North Yellow Sea 被引量:3
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作者 Pietro Franco CHEN Hongju LIU Guangxing 《Journal of Ocean University of China》 SCIE CAS 2014年第5期782-790,共9页
In this paper, the distribution patterns and abundance of pelagic tunicates in the North Yellow Sea of China during the period 2006-2007 were analyzed. Zooplankton samples were obtained with vertical towing from botto... In this paper, the distribution patterns and abundance of pelagic tunicates in the North Yellow Sea of China during the period 2006-2007 were analyzed. Zooplankton samples were obtained with vertical towing from bottom to surface using a WP2 plankton net(200 μm mesh size; mouth area: 0.25 m2). Five species belonging to two classes were identified: Oikopleura dioica, O. longicauda and Fritillaria borealis belonging to class Appendicularia; Salpa fusiformis and Doliolum denticulatum of class Thaliacea. O. dioica and O. longicauda were the dominant species, occurring in the samples of all four seasons, with different distribution patterns. Their maximum abundance were 1664.7 ind. m-3(spring) and 1031.7 ind. m-3(spring) respectively. Following Oikopleura spp. were D. denticulatum, which was found only in autumn with an average abundance of 149.6 ind. m-3, and S. fusiformis, which was detected all the year long except for autumn with low abundance(max. abundance 289.4 ind. m-3 in summer). Only a very small amount of F. borealis was detected in summer samples, with an average abundance of 2.7 ind. m-3. The relationship between tunicates abundances and the environmental factors was analyzed using the stepwise regression model for each species. The variation of appendicularian abundance showed a significant correlation with the surface water temperature and with the concentration of Chl-a. No relationship was found between tunicates abundance and salinity, likely due to the slight changes in surface salinity of the studied area during the four seasons. Salps abundance and that of doliolids were significantly correlated to bottom water temperature, indicating that these two species(S. fusiformis and D. denticulatum) migrate vertically in the water column. In particular D. denticulatum, known to be a warm water species, showed not only an important correlation with water temperature, but also a spatial distribution connected to the warm currents in the North Yellow Sea. The occurrence of D. denticulatum represents an interesting result never found in past research work. Water temperature, algal distribution and currents were the most relevant environmental factors influencing the tunicate abundance and distribution in the North Yellow Sea. Further research is needed in order to get more information on the ecology of these organisms and to better understand their role in the ecosystem including the oceanic food web. 展开更多
关键词 North Yellow Sea pelagic tunicates ABUNDANCE DISTRIBUTION sea surface temperature
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Accuracy Analysis on Bundle Adjustment of Remote Sensing Images Based on Dual Quaternion 被引量:1
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作者 盛庆红 费利佳 +2 位作者 柳建锋 陈姝文 王惠南 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2015年第5期523-529,共7页
A bundle adjustment method of remote sensing images based on dual quaternion is presented,which conducted the uniform disposal corresponding location and attitude of sequence images by the dual quaternion.The constrai... A bundle adjustment method of remote sensing images based on dual quaternion is presented,which conducted the uniform disposal corresponding location and attitude of sequence images by the dual quaternion.The constraint relationship of image itself and sequence images is constructed to compensate the systematic errors.The feasibility of this method used in bundle adjustment is theoretically tested by the analysis of the structural characteristics of error equation and normal equation based on dual quaternion.Different distributions of control points and stepwise regression analysis are introduced into the experiment for RC30 image.The results show that the adjustment accuracy can achieve 0.2min plane and 1min elevation.As a result,this method provides a new technique for geometric location problem of remote sensing images. 展开更多
关键词 photogrammetry bundle adjustment geometric correction dual quaternion geometric imaging model
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Effect of Deficit Irrigation at Different Growth Stages on Wheat Growth and Yield 被引量:1
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作者 Seyed Abdolreza Kazemeini Mohsen Edalat 《Journal of Life Sciences》 2011年第1期35-38,共4页
In order to evaluate the effect of deficit irrigation at various growth stages on wheat growth and yield, a field experiment was conducted in the 2008-2009 growing season based on the completely randomized block with ... In order to evaluate the effect of deficit irrigation at various growth stages on wheat growth and yield, a field experiment was conducted in the 2008-2009 growing season based on the completely randomized block with four replications at the experimental farm of the College of Agriculture, Shiraz University, Shiraz, Iran, located at Badjgah. Treatments involved 13 irrigation regimes which applied in stem elongation, heading and grain filling growth stages. The highest seed yield (4,333 kg-ha-1) and the lowest ones (1,377 kg'hal) were obtained from T1 (100% field capacity (FC) in all growth stages) and T13 (50% FC in all growth stages), respectively. With limitation in water amount seed yield was diminished, but this trend was not significant at T4 (100%, 100% and 50% FC) and TI 1 (100%, 100% and 75~/0 FC). Stepwise regression results revealed that, seed number per spike had the largest contribution (partial R2 = 0.72) in seed yield variation. Also at TI, T4, and TI 1 treatments (well water treatments) as well as TI3 (sever stress) head number m2 contribute most in seed yield determination (partial R2 = 0.96). It can be concluded that water shortage during the grain filling period and its allocation to the other consecutive crop, can increase crop production in southern regions of Iran. 展开更多
关键词 Deficit irrigation yield components WHEAT stepwise regression.
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Comparative Analysis of the Determinants of Residential Land Values 被引量:1
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作者 Ilechukwu Victor Uju Salau Taofik Iyanda 《Chinese Business Review》 2012年第2期187-192,共6页
City development is a result of many factors, of which land value is one of the major determinants. The past urban economics studies have shown that land value is largely determined by location factors such as distanc... City development is a result of many factors, of which land value is one of the major determinants. The past urban economics studies have shown that land value is largely determined by location factors such as distance from Central Business District (CBD) ignoring the non-location factors like time of purchase and neighbourhood infrastructures. Therefore, this paper attempts to establish the relative importance of location and non-location factors in the determination of residential land value by positing Onitsha, Nigeria as a case study. Eight hundred and fifty residential housing units were selected and questionnaire administered to the landlords through multi-stage sampling technique. The stepwise regression analysis results showed that non-location factors, especially, time of land purchase, contribute more to the variation in residential land values. The paper suggests the revision of the classical economic theories to represent the conditions of urban areas in developing countries . 展开更多
关键词 residential land value location factors non-location factors
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Tolerance, Oxygen Consumption and Ammonia Excretion of Ophiopholis sarsii vadicola in Different Temperatures and Salinities
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作者 FANG Jinghui ZHANG Jihong +5 位作者 JIANG Zengjie ZHAO Xuewei JIANG Xu DU Meirong GAO Yaping FANG Jianguang 《Journal of Ocean University of China》 SCIE CAS 2015年第3期549-556,共8页
There are more than 2000 species of brittle stars in the world. For most of them, many scientific questions including basic characteristics of eco-physiology are still unknown. In the present study, Ophiopholis sarsii... There are more than 2000 species of brittle stars in the world. For most of them, many scientific questions including basic characteristics of eco-physiology are still unknown. In the present study, Ophiopholis sarsii vadicola acclimated at 15 ℃, salinity 31, were assessed for temperature monia excretion were studied at different temperatures (5, 10, and salinity tolerance. Its oxygen consumption and am- 15, 20, 25℃) and salinities (25, 30, 35). O. sarsii vadi- cola could tolerate 0-24℃ and no brittle star was dead in the salinity range of 19-48 in the experimental situation. Two-way ANOVA showed that the oxygen consumption and ammonia excretion normalized with both dry mass and wet mass, Q10, which is used to describe the temperature sensitivity of respiration, and moisture content were significantly affected by temperature and salinity, and the combined effects of the two factors were significant. Stepwise multiple regression analysis revealed that logarithmic oxygen consumption and ammonia excretion showed a significant positive relationship with logarithmic temperature and salinity. The logarithmic moisture content of the brittle stars showed an inverse relationship with logarithmic salinity, but a positive relationship with logarithmic temperature. This suggests that the tolerance of temperature and salinity of brittle stars is closely related to their living environment, and that the effects of temperature on oxygen consumption are more significant at higher salinity, and that the ammonia excretion is less affected by salinity at lower temperatures. 展开更多
关键词 Ophiopholis sarsii vadicola TOLERANCE oxygen consumption ammonia excretion TEMPERATURE SALINITY
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