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从“归物”看王维山水诗歌
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作者 赖爱清 《四川理工学院学报(社会科学版)》 2008年第5期111-114,共4页
"归物"不是自然的人化而是自然的自然化,人类要以观照而不是改造的态度去面对自然,这就是自然的"自然化",也就是我们所说的"归物"。人类要与自然协调共在,达到一种审美化的人生,就必须保持一种使自然&qu... "归物"不是自然的人化而是自然的自然化,人类要以观照而不是改造的态度去面对自然,这就是自然的"自然化",也就是我们所说的"归物"。人类要与自然协调共在,达到一种审美化的人生,就必须保持一种使自然"自然化"的距离。王维笔下的山水是超越功利,摆脱主体情感的纯任自然的山水,是达到"无我之境"的最高审美境界。以"无欲之我"观物,方能达"无我之境","以物观物"是以万物之理观物,王维笔下的自然是以物观物的自然,是自然化而非人化的自然,是"天机清妙者"的无我之境,体现了人与自然的和谐共处,臻于优美之至境。 展开更多
关键词 归物 自然 无我之境
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基于微信平台的寻物归物系统的创业探索 被引量:1
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作者 唐伟杰 叶凤娇 刘露 《信息系统工程》 2019年第4期156-156,共1页
在日常生活中丢失物品已经是一种普遍存在的现象了,物品的丢失会影响到人们的日常生活,对工作也会造成一定的影响。目前已有的寻物系统存在诸多问题,在互联网技术高速发展背景下,很多传统行业都与新兴的互联网技术相结合,从而形成了一... 在日常生活中丢失物品已经是一种普遍存在的现象了,物品的丢失会影响到人们的日常生活,对工作也会造成一定的影响。目前已有的寻物系统存在诸多问题,在互联网技术高速发展背景下,很多传统行业都与新兴的互联网技术相结合,从而形成了一种新的发展形态,为人们的生活及工作提供了便利。鉴于此,论文提出了一种基于微信平台的智能寻物归物系统,并进行了创业的分析与探索。 展开更多
关键词 智能寻归物 创业
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Normalized edge detection, and the horizontal extent and depth of geophysical anomalies 被引量:2
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作者 李丽丽 韩立国 黄大年 《Applied Geophysics》 SCIE CSCD 2014年第2期149-157,252,253,共11页
Edge detection is an image processing technique for finding the boundaries of objects within images. It is typically used to interpret gravity and magnetic data, and find the horizontal boundaries of geological bodies... Edge detection is an image processing technique for finding the boundaries of objects within images. It is typically used to interpret gravity and magnetic data, and find the horizontal boundaries of geological bodies. Large deviations between model and true edges are common because of the interference of depth and errors in computing the derivatives; thus, edge detection methods cannot provide information about the depth of the source. To simultaneously obtain the horizontal extent and depth of geophysical anomalies, we use normalized edge detection filters, which normalize the edge detection function at different depths, and the maxima that correspond to the location of the source. The errors between model and actual edges are minimized as the depth of the source decreases and the normalized edge detection method recognizes the extent of the source based on the maxima, allowing for reliable model results. We demonstrate the applicability of the normalized edge detection filters in defining the horizontal extent and depth using synthetic and actual aeromagnetic data. 展开更多
关键词 geophysical anomalies normalized edge detection normalized total horizontal derivative regularization tilt angle theta map
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On the Biomass of Four Major Tree Species in Vegetation Restoration Pattern Area of Beichuan Nature Reserve
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作者 冯永林 沈金亮 +6 位作者 张建设 邓东周 邵文 王刚 孙志鹏 苏春英 王刚 《Agricultural Science & Technology》 CAS 2015年第10期2337-2340,2346,共5页
In the experiment, by taking Quercus engleriana Seem., Betula albo- sinensis Burk., Abies faxoniana Rehd. and Fargesia rufa Yi, in the vegetation restoration pattern area of Beichuan Nature Reserve as the research obj... In the experiment, by taking Quercus engleriana Seem., Betula albo- sinensis Burk., Abies faxoniana Rehd. and Fargesia rufa Yi, in the vegetation restoration pattern area of Beichuan Nature Reserve as the research objects, the study on the biomass models, the biomass distribution law of single plant and the growth rule of every organ of the four tree species was made. The results indicated that in the compositions of all of the species, the proportion of trunk biomass was the highest, while that of trunk biomass was the lowest, the proportions of branch and root biomasses varied depending on species; in the comparison of correlativity between the proportions of biomasses of all nutrition organs and biomass of single plant, the relations were generally significant, the tree trunks were positively related while the roots were negatively related; the proportion of trunk biomass of all species was significantly and negatively related to the proportions of leaf and branch biomasses, while the biomass of leaves was significantly and positively related to the biomass of branches. 展开更多
关键词 Beichuan Nature Reserve BIOMASS Regression model Allocation pro- portion
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Lamé parameters inversion based on elastic impedance and its application 被引量:23
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作者 Wang Baoli Yin Xingyao Zhang Fanchang 《Applied Geophysics》 SCIE CSCD 2006年第3期174-178,共5页
The Connolly (1999) elastic impedance (EI) equation is a function of P-wave velocity, S-wave velocity, density, and incidence angle. Conventional inversion methods based on this equation can only extract P-velocit... The Connolly (1999) elastic impedance (EI) equation is a function of P-wave velocity, S-wave velocity, density, and incidence angle. Conventional inversion methods based on this equation can only extract P-velocity, S-velocity, and density data directly and the elastic impedance at different incidence angles are not at the same scale, which makes comparison difficult. We propose a new elastic impedance equation based on the Gray et al. (1999) Zoeppritz approximation using Lamé parameters to address the conventional inversion method's deficiencies. This equation has been normalized to unify the elastic impedance dimensions at different angles and used for inversion. Lamé parameters can be extracted directly from the elastic impedance data obtained from inversion using the linear relation between Lamé parameters and elastic impedance. The application example shows that the elastic parameters extracted using this new method are more stable and correct and can recover the reservoir information very well. The new method is an improvement on the conventional method based on Connolly's equation. 展开更多
关键词 Gray approximation elastic impedance inversion NORMALIZATION and Lamé parameter.
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Comprehensive tests on rising height of capillary water for coarse grained soil 被引量:4
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作者 GUO Qingsong LI Xin LI Min 《Global Geology》 2013年第1期54-58,共5页
According to the comprehensive tests on the rising height of capillary water for seven kinds of differ- ent coarse grained soil by use of the method of standpipe, the relationship between the rising height of capillar... According to the comprehensive tests on the rising height of capillary water for seven kinds of differ- ent coarse grained soil by use of the method of standpipe, the relationship between the rising height of capillary water and time was obtained, and the influencing factors and rules were analyzed. The data of the steady rising height of capillary water were obtained, and the regression equation of coarse grained soil on steady height and physical indexes (effective grain dl0 and porosity n) was found. Compared with Hazen's and other expressions that could estimate the steady height of capillary water of coarse grained soil, the proposed method is satisfactory and the defects of the latter were pointed out. 展开更多
关键词 method of standpipe coarse grained soil rising height of capillary water degree of compaction
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Beak Measurements of Octopus (Octopus variabilis) in Jiaozhou Bay and Their Use in Size and Biomass Estimation 被引量:2
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作者 XUE Ying REN Yiping +4 位作者 MENG Wenrong LI Long MAO Xia HAN Dongyan MA Qiuyun 《Journal of Ocean University of China》 SCIE CAS 2013年第3期469-476,共8页
Cephalopods play key roles in global marine ecosystems as both predators and preys.Regressive estimation of original size and weight of cephalopod from beak measurements is a powerful tool of interrogating the feeding... Cephalopods play key roles in global marine ecosystems as both predators and preys.Regressive estimation of original size and weight of cephalopod from beak measurements is a powerful tool of interrogating the feeding ecology of predators at higher trophic levels.In this study,regressive relationships among beak measurements and body length and weight were determined for an octopus species(Octopus variabilis),an important endemic cephalopod species in the northwest Pacific Ocean.A total of 193 individuals(63 males and 130 females) were collected at a monthly interval from Jiaozhou Bay,China.Regressive relationships among 6 beak measurements(upper hood length,UHL;upper crest length,UCL;lower hood length,LHL;lower crest length,LCL;and upper and lower beak weights) and mantle length(ML),total length(TL) and body weight(W) were determined.Results showed that the relationships between beak size and TL and beak size and ML were linearly regressive,while those between beak size and W fitted a power function model.LHL and UCL were the most useful measurements for estimating the size and biomass of O.variabilis.The relationships among beak measurements and body length(either ML or TL) were not significantly different between two sexes;while those among several beak measurements(UHL,LHL and LBW) and body weight(W) were sexually different.Since male individuals of this species have a slightly greater body weight distribution than female individuals,the body weight was not an appropriate measurement for estimating size and biomass,especially when the sex of individuals in the stomachs of predators was unknown.These relationships provided essential information for future use in size and biomass estimation of O.variabilis,as well as the estimation of predator/prey size ratios in the diet of top predators. 展开更多
关键词 Octopus variabilis Jiaozhou Bay beak measurement body size hood length crest length
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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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Several boundary identification methods of gravity data and application in Vientiane of Laos area 被引量:2
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作者 LI Lin WU Yangang +2 位作者 YANG Changbao HUAN Hengfei GUO Cancan 《Global Geology》 2014年第1期55-61,共7页
The authors studied the potential field boundary identification of the new technology in order to find out the possible fractures or contact zones using the following methods such as tilt derivative,horizontal derivat... The authors studied the potential field boundary identification of the new technology in order to find out the possible fractures or contact zones using the following methods such as tilt derivative,horizontal derivative of tilt derivative,normalized standard deviation and normalized differential method. Combined with Euler deconvolution and small subdomain filtering,the actual data processing results show that these methods are all able to identify wider range extending fractures and obtain abundant geological information. The horizontal derivative of tilt derivative and normalized differential method have a better resolution for the small cutting fractures and lacunae in the studied area. They provide a reliable basis for study of the cutting relationship between fractures. 展开更多
关键词 potential field boundary identification fracture detect Vientiane Laos
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Synthesis,algal inhibition activities and QSAR studies of novel gramine compounds containing ester functional groups 被引量:2
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作者 李霞 于良民 +2 位作者 姜晓辉 夏树伟 赵海洲 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第2期309-316,共8页
2,5,6-Tribromo-l-methylgramine (TBG), isolated from bryozoan Zoobotryon pellucidum was shown to be very efficient in preventing recruitment of larval settlement. In order to improve the compatibility of TBG and its ... 2,5,6-Tribromo-l-methylgramine (TBG), isolated from bryozoan Zoobotryon pellucidum was shown to be very efficient in preventing recruitment of larval settlement. In order to improve the compatibility of TBG and its analogues with other ingredients in antifouling paints, structural modification of TBG was focused mainly on halogen substitution and N-substitution. Two halogen-substitute gramines and their derivatives which contain ester functional groups at N-position of gramines were synthesized. Algal inhibition activities of the synthesized compounds against algae Nitzschia cIosterium were evaluated and the Median Effective Concentration (EC50) range was 1.06-6.74 lag ml^-1. Compounds that had a long chain ester group exhibited extremely high antifouling activity. Quantitive Structure Activity Relationship (QSAR) studies with multiple linear regression analysis were applied to fred correlation between different calculated molecular descriptors and biological activity of the synthesized compounds. The results show that the toxicity (log (I/EC50)) is correlated well with the partition coefficient log P. Thus, these products have potential function as antifouling agents. 展开更多
关键词 gramine derivative SYNTHESIS algal inhibition activity QSAR
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Shape and Mechanical Behavior of Geotextile Tubes 被引量:6
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作者 张文斌 谭家华 《Journal of Donghua University(English Edition)》 EI CAS 2006年第2期8-12,共5页
Nowadays, geotextile tubes hydraulically filled with dredged materials have been used in the application of cofferdam, sea reclamation and deepwater channel regulation in China. The shape and mechanical behaviors duri... Nowadays, geotextile tubes hydraulically filled with dredged materials have been used in the application of cofferdam, sea reclamation and deepwater channel regulation in China. The shape and mechanical behaviors during the process of filling, consolidation and stacked are one of the main problems concemed by designers and researchers.This paper uses the method of elliptic integrals to study the behaviors of filling and deduces the regressive formulas of shape features and circumferential tension. The results show that the proposal regressive formulas are only the function of pressure at bottom; they are very convenient and suitable for the filling design. When the filling materials are sandy, the shape and mechanical behaviors nearly remain during the process of consolidation. The behaviors of stacked geotextile tubes are very complex, because they are involved in the properties of the filling material, geotextile and foundation.Using the commercial finite element analysis program ABAQUS, this paper establishes the entire 2- D finite element load model to investigate, which include the part of filling material, geotextile and foundation. The numerical results suggest that the maximun circumferential tension varies with the properties of filling materials and foundations, whereas the largest tensile force occurs during the filling process. 展开更多
关键词 geotextile tubes regressive formulas ABAQUS mechanical behaviors.
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Abundance and spatial dynamics of bacterioplankton in the Seven Rila Lakes,Bulgaria 被引量:2
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作者 Silvena BOTEVA Ivan TRAYKOV +1 位作者 Anelia KENAROVA Valentin BOGOEV 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第3期451-458,共8页
In the high mountain oligotrophic Seven Rila Lakes (2 095–2 535 m a.s.l.) bacterial abundance was recorded in July and September 2006. In July, bacterial abundance (average (3.32±2.5)×105 cell/ml) in the la... In the high mountain oligotrophic Seven Rila Lakes (2 095–2 535 m a.s.l.) bacterial abundance was recorded in July and September 2006. In July, bacterial abundance (average (3.32±2.5)×105 cell/ml) in the lakes correlated negatively with elevation, while in September (average (26.39±7.1)×105 cell/ml) this pattern was altered and the greatest abundance of bacteria occurred at the highest ((39.05±1.5)×105 cell/ml) and the lowest ((30.63±6.0)×105 cell/ml) elevated lakes. Regression analyses suggested that the principal factor controlling bacterial abundance, in both July and September, was inorganic nitrogen (NO3-N and NH4-N; R2=0.70, P<0.05). Other major regulating factors were temperature (R2=0.66, P<0.03) in July and filter-feeding zooplankton (R2=0.95, P<0.01) in September. All factors, except NO3-N, had a positive effect on bacterial abundance. 展开更多
关键词 bacterial abundance high mountain lake Rila Mountain environmental factor bottom-up control
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Estimation of the Above-ground Biomass of Tamarix Species along a Transect at the Tarim River's Middle Reaches 被引量:3
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作者 努尔比亚.阿布力米提 努尔巴依.阿布都沙力克 +1 位作者 于苏云江.吗米提敏 Niels Thevs 《Agricultural Science & Technology》 CAS 2011年第2期301-304,共4页
[Objective] The purpose was to research the distribution characteristics of Tamarix species above-ground biomass of Tarim River's middle reaches and to find out best-fit linear-regression model of Tamarix species in ... [Objective] The purpose was to research the distribution characteristics of Tamarix species above-ground biomass of Tarim River's middle reaches and to find out best-fit linear-regression model of Tamarix species in this area.[Method] By dint of the most common sampling method PCQ,five samples in the middle reaches of Tarim River were collected.The best-fit linear-regression model of Tamarix species of this area was set up,based on the fieldwork and the model of Evangelista and obtained the distribution rules of Tamarix species of Tarim River's middle reaches.[Result] The result indicated that this model fitted for the estimation of aboveground biomass of the study area.According to the distribution rules of aboveground biomass,it was clear that underground water was the major element which decided the distribution of aboveground biomass.[Conclusion] The study provided theoretical basis for the calculation of biomass of Tamarix. 展开更多
关键词 Above-ground biomass Tamarix species Linear-regression analysis
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STUDY ON THE INTERACTION BETWEEN NDVI PROFILE AND THE GROWING STATUS OF CROPS 被引量:16
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作者 JIANGDong WANGNai-bin +1 位作者 YANGXIao-huan WANGJi-hua 《Chinese Geographical Science》 SCIE CSCD 2003年第1期62-65,共4页
Daily and ten-day Normalized Difference Vegetation Index( NDVI) of crops were retrieved from meteorological satellite NOAA AVHRR images. The temporal variations of the NDVI were analyzed during the whole growing seaso... Daily and ten-day Normalized Difference Vegetation Index( NDVI) of crops were retrieved from meteorological satellite NOAA AVHRR images. The temporal variations of the NDVI were analyzed during the whole growing season, and thus the principle of the interaction between NDVI profile and the growing status of crops was discussed. As a case in point, the relationship between integral NDVI and winter wheat yield of Henan Province in 1999 had been analyzed. By putting integral NDVI values of 60 sample counties into the winter wheat yield-integral NDVI coordination, scattering map was plotted. It demonstrated that integral NDVI had a close relation with winter wheat yield. These relation could be described with linear, cubic polynomial, and exponential regression, and the cubic polynomial regression was the best way. In general, NDVI reflects growing status of green vegetation, so crop monitoring and crop yield estimation could be realized by using remote sensing technique on the basis of time serial NDVI data together with agriculture calendars. 展开更多
关键词 NDVI PROFILE growing status CROP
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Estimation of surface tension of organic compounds using quantitative structure-property relationship 被引量:2
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作者 戴益民 刘又年 +3 位作者 李浔 曹忠 朱志平 杨道武 《Journal of Central South University》 SCIE EI CAS 2012年第1期93-100,共8页
A novel quantitative structure-property relationship (QSPR) model for estimating the solution surface tension of 92 organic compounds at 20℃ was developed based on newly introduced atom-type topological indices. Th... A novel quantitative structure-property relationship (QSPR) model for estimating the solution surface tension of 92 organic compounds at 20℃ was developed based on newly introduced atom-type topological indices. The data set contained non-polar and polar liquids, and saturated and unsaturated compounds. The regression analysis shows that excellent result is obtained with multiple linear regression. The predictive power of the proposed model was discussed using the leave-one-out (LOO) cross-validated (CV) method. The correlation coefficient (R) and the leave-one-out cross-validation correlation coefficient (Rcv) of multiple linear regression model are 0.991 4 and 0.991 3, respectively. The new model gives the average absolute relative deviation of 1.81% for 92 substances. The result demonstrates that novel topological indices based on the equilibrium electro-negativity of atom and the relative bond length are useful model parameters for QSPR analysis of compounds. 展开更多
关键词 surface tension quantitative structure-property relationship (QSPR) topological indice organic compound
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Establishment and Analysis of Regression Models between Sowing Time and Plant Productivity, Biological Yield of Forage Sorghum in Autumn Idle Land 被引量:1
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作者 ZHOU Han-zhang LIU Hong-xia +4 位作者 LIU Huan ZHOU Xin-jian WEI Zhi-min HOU Sheng-lin LI Shun-guo 《Agricultural Science & Technology》 CAS 2018年第1期51-58,共8页
[Objective]The aim was to establish the linear regression prediction models between sowing time and plant productivity, biological yield of forage sorghum in autumn idle land.[Method]The relationships between sowing t... [Objective]The aim was to establish the linear regression prediction models between sowing time and plant productivity, biological yield of forage sorghum in autumn idle land.[Method]The relationships between sowing time and plant productivity, biological yield of forage sorghum were simulated and compared by using field experiment and linear regression analysis.[Result] The sowing time had an important influence on the plant productivity and biological yield of forage sorghum in autumn idle land. The plant productivity and biological yield of forage sorghum both decreased with the delay of sowing time.The regression model between plant fresh weight and sowing time was ?fresh=0.618-0.015x; the regression model between plant dry weight and sowing time was ?dry=0.184-0.005x; and the regression model between biological yield and sowing time was yield=29 126.461-711.448x. During July 23rd to August 30th, when the sowing time was delayed by 1 day, the plant fresh weight of forage sorghum was reduced by 0.015 g, the plant dry weight was reduced by 0.005 g, and the yield was reduced by 711.448 kg/hm2. [Conclusion] The three regression models established in this study will provide theoretical support for the production of forage sorghum. 展开更多
关键词 Autumn idle land Forage sorghum Sowing time Plant productivity Biological yield Regression model Regression analysis
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Sharing Culture and Belonging Through Cross-Cultural Collaborative Painting
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作者 Vanessa Maree Barbay 《Journal of Literature and Art Studies》 2014年第6期483-488,共6页
The topic of this paper is animals in painting and the investigative process undertaken by the artist Vanessa Barbay during her practice--led Ph.D.. Her aim was to discover a way to present deceased animals that retai... The topic of this paper is animals in painting and the investigative process undertaken by the artist Vanessa Barbay during her practice--led Ph.D.. Her aim was to discover a way to present deceased animals that retained their agency as individuals by challenging the objectifying nature of representation. The foundation of this method was the collaboration between artist and dead animal subjects through harnessing the natural decomposition of the subject in order to generate their image. A related stream of Barbay's research was learning about the art and culture of Kunwinjku speaking artists living in Kunbarlanja Western Amhem Land where artists have painted images of animals on rock shelters and on bark from ancient through to contemporary times. The significance of their form of animal representation is a mythopoeic relationship between locally found pigments and animal bodies. Paintings are considered as collaboration between matter, subject, and artist, which Barbay extends in her current work centred on collaborative painting involving more than one artist. 展开更多
关键词 PAINTING ANIMALS PIGMENTS Kunwinjku SHROUD decomposition
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Kinetics of Atmospheric Corrosion of Mild Steel in Marine and Rural Environments 被引量:4
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作者 S. Palraj M. Selvaraj K. Maruthan M. Natesan 《Journal of Marine Science and Application》 CSCD 2015年第1期105-112,共8页
In continuation of the extensive studies carried out to update the corrosion map of India, in this study, the degradation of mild steel by air pollutants was studied at 16 different locations from Nagore to Ammanichat... In continuation of the extensive studies carried out to update the corrosion map of India, in this study, the degradation of mild steel by air pollutants was studied at 16 different locations from Nagore to Ammanichatram along the east coast of Tamilnadu, India over a period of two years. The weight loss study showed that the mild steel corrosion was more at Nagapattinam site, when compared to Ammanichatram and Maravakadu sites. A linear regression analysis of the experimental data was attempted to predict the mechanism of the corrosion. The composition of the corrosion products formed on the mild steel surfaces was identified by XRD technique. The corrosion rate values obtained are discussed in the light of the weathering parameters, atmospheric pollutants such as salt content & SO2 levels in the atmosphere, corrosion products formed on the mild steel surfaces. 展开更多
关键词 KINETICS atmospheric corrosion mild steel XRD weight loss
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Sedentary behavior and physical activity predicting depressive symptoms in adolescents beyond attributes of health-related physical fitness 被引量:1
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作者 gene l.farren tao zhang +1 位作者 xiangli gu katherine t.thomas 《Journal of Sport and Health Science》 SCIE 2018年第4期489-496,共8页
Background: Sedentary behavior (SB), physical activity (PA), and attributes of physical fitness have been shown to be related to depressive symptoms in adolescents. The purpose of the present study was to investi... Background: Sedentary behavior (SB), physical activity (PA), and attributes of physical fitness have been shown to be related to depressive symptoms in adolescents. The purpose of the present study was to investigate whether SB and fitness-producing activity predicted depression in active adolescents over and above gender and fitness attributes. Methods: Participants were 249 adolescents (age: 12.85 ± 0.89 years, mean ± SD) from 3 public middle schools who wore Actical accelerometers to assess their SB and PA. Participants also completed the FITNESSGRAM health-related fitness assessment and a brief depression questionnaire. A 3-step hierarchical regression analysis was conducted with gender and fitness attributes (i.e., body mass index (BMI), maximal volume oxygen uptake (VO2max), curlups, and pushups), moderate- and vigorous-intensity activity, and SB entered in respective steps. Results: Regression analysis indicated activity variables (i.e., moderate- and vigorous-intensity activity) significantly predicted depression (△R^2= 0.12, p 〈 0.01) beyond gender and fitness attributes. Overall, gender, fitness attributes, activity variables, SB explained 31% of the variance in depression. Structure coefficients revealed VO2max (rs= -0.77), moderate-intensity activity (rs= -0.67), vigorous-intensity activity (rs = -0.81), and SB (rs = 0.57) were substantially correlated with the criterion variable; thus, they were the strongest predictors of depression. Conclusion: The findings of the current study indicated SB and PA were both significant predictors of depression; however, sufficient fitness-producing activity and adequate cardiorespiratory fitness may nullify the negative influence of SB on depressive symptoms in active adolescents.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 Accelerometers Adolescent health Cardiorespiratory fitness FITNESSGRAM Mental health Moderate-to-vigorous-intensity activity
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Evaluation of the diagnostic value of tumor markers with ROC and logistic regression in gastrocolic tumors
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作者 Jinbo Liu Mingsu Zhou Yonglun Hang Meizhu Cai Min Song Ting Ye Kaizheng Wang 《The Chinese-German Journal of Clinical Oncology》 CAS 2011年第11期650-653,共4页
Objective: The aim of the study was to evaluate the clinical significance of multiple tumor markers (CEA, AFP, CA72-4 and CA19-9) in patients with gastrocolic tumors by receiver operating characteristic (ROC) curve an... Objective: The aim of the study was to evaluate the clinical significance of multiple tumor markers (CEA, AFP, CA72-4 and CA19-9) in patients with gastrocolic tumors by receiver operating characteristic (ROC) curve and stepwise logistic regression (LR) analysis. Methods: The serum concentrations of CEA, AFP, CA72-4 and CA19-9 were measured with electrochemiluminescence immunoassay in 126 patients with gastrocolic tumors, 137 patients with benign gastrocolic disorders and 109 healthy controls. The area under the ROC curve (AUC) of CEA, AFP, CA72-4 and CA19-9 and stepwise LR results were compared by sensitivity, specificity, Youden's index and positive likelihood ratio/negative likelihood ratio. Results: The levels of four tested tumor markers in patients with gastrocolic tumors were significantly higher than those in benign gastrocolic group and normal controls. In the benign gastrocolic group, the AUC from stepwise logistic regression was larger than the AUC of four tumor markers respectively. Sensitivity, Youden's index and positive likelihood ratio/negative likelihood ratio were the highest in the combination assay of CA72-4, CEA, and CA19-9, as compared with one of the tumor markers alone. Conclusion: The use of ROC established by LR analysis model improved the diagnostic accuracy of gastrocolic tumors. For the screening of gastrocolic tumors, the AUC value of the combination probability index (sensitivity and specificity) was significantly higher than the values of the different tumour markers. 展开更多
关键词 gastrocolic tumor tumor marker (TM) receiver operating characteristic (ROC) curve logistic regression (LR)analysis diagnosis
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