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Censored Composite Conditional Quantile Screening for High-Dimensional Survival Data
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作者 LIU Wei LI Yingqiu 《应用概率统计》 CSCD 北大核心 2024年第5期783-799,共17页
In this paper,we introduce the censored composite conditional quantile coefficient(cC-CQC)to rank the relative importance of each predictor in high-dimensional censored regression.The cCCQC takes advantage of all usef... In this paper,we introduce the censored composite conditional quantile coefficient(cC-CQC)to rank the relative importance of each predictor in high-dimensional censored regression.The cCCQC takes advantage of all useful information across quantiles and can detect nonlinear effects including interactions and heterogeneity,effectively.Furthermore,the proposed screening method based on cCCQC is robust to the existence of outliers and enjoys the sure screening property.Simulation results demonstrate that the proposed method performs competitively on survival datasets of high-dimensional predictors,particularly when the variables are highly correlated. 展开更多
关键词 high-dimensional survival data censored composite conditional quantile coefficient sure screening property rank consistency property
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Induced Expression of Cytochrome P450 CYP305 B1V1 Gene in Different Tissues of Wild Mulberry Silkworm(Bombyx mandarina) 被引量:6
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作者 路爱成 卫正国 +1 位作者 李兵 沈卫德 《Agricultural Science & Technology》 CAS 2009年第2期54-58,共5页
[ Objective] The aim of this study was to investigate effects of various inducers on the expression of cytochrome P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm. [ Method] Referring to the mRNA ... [ Objective] The aim of this study was to investigate effects of various inducers on the expression of cytochrome P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm. [ Method] Referring to the mRNA sequence of CYP305 B1 V1 Gene published in GenBank for wild mulberry silkworm, one pair of primers was designed, and the expression of cytochrome P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm treated by NaF, rutin, cypermethrin and ecdysone was also analyzed by the semi - quantitative RT - PCR. Furthermore, homology comparison and phylogenetic analysis for amino acid sequences of this gene were studied. [ Result] Rutin, cypermethrin and NaF had effects on the expression of P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm, while ecdysone had no significant effect. Homology comparison for amino acids indicated that the amino acid sequence of this gene was the most similar to that of CYP305 B1 gene in Bombyx mori with 100% amino acid identity, and highly similar to those of Tribolium casmneum CYP305A1, Apis mellifera CYP305A1, Drosophi- la melanogaster CYP305A1, Anopheles gambiae CYP305A2and Culex pipiens quinquefasciatus CYP2LI. [ Conclusion] CYP305 B1 V1 Gene of wild mulberry silkworm is likely to mainly take part in the metabolism of exogenous compounds, which is of great significance for revealing the function of cytochrome P450 and the metabolic mechanism of different drugs. 展开更多
关键词 Wild mulberry silkworm CYP305B1V1 INDUCE EXPRESSION Phylogenetic analysis
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Soil Physical and Chemical Properties of Five Subtropical Forests in Lingao of Hainan
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作者 薛杨 宿少锋 +1 位作者 王小燕 林之盼 《Agricultural Science & Technology》 CAS 2017年第8期1459-1464,共6页
With 5 types of typical forests as research object, the physical and chemical properties of different types of forests were analyzed by sample plot investigation method. The results showed that: the soil total porosi... With 5 types of typical forests as research object, the physical and chemical properties of different types of forests were analyzed by sample plot investigation method. The results showed that: the soil total porosity was the highest in the Casuarina equisetifolia forest (46.168%), but the lowest in the Encalyptus robusta forest (39.46%). The soil capillary porosity was the highest in the Acacia mangium forest (22.57%), but the lowest in the secondary forest (18.95%). The soil water content was the highest in the C. equisetifolia forest, with a mean value of 27.85%, but the lowest in the secondary forest, with a mean value of 4.34%. The soil pH values were in the range of 4.81-6.59, the soils in the A. mangium forest, C. equisetifolia forest and E. robusta forest were strongly acidic (pH 4.5-5.5), and the soils in the secondary forest and C. nucifera forest were weakly acidic. The soils had organic matter contents in the range of 0.34-28.68 g/kg, and showed an order of A. mangium forest〉C. equisetifolia forest〉E. robusta forest〉secondary forest〉C. nucifera forest, with a decreasing trend with the soil depth increasing. The soil total N contents were in the range of 0.10-1.63 g/kg, the A. mangium forest showed the highest soil total N contents, while the C. nucifera forest exhibited the lowest soil total N contents; the soil total P contents were in the range of 0.21-1.74 g/kg, and the E. robusta forest had the highest soil total P contents; and the soil total K contents were in the range of 0.16-2.15 g/kg, and the A. mangium forest exhibited the highest soil total K contents. The soil available P contents were in the range of 0.98-132.46 mg/kg; and the secondary forests had the highest soil available P contents; and the soil rapidly available K contents were in the range of 3.03-27.35 mg/kg, and the C. nucifera forest exhibited the highest soil rapidly available K contents. The soil ammonium N contents were in the range of 1.38-5.15 mg/kg, and the nitrate N contents were in the range were in the range of 0.56 -3.51 mg/kg. The A. mangium forest showed the highest soil nitrate N contents (with a mean value of 2.29 mg/kg) and ammonium N contents (with a mean value of 3.93 mg/kg). For the same forest type, with the increase of soil depth, the nitrate nitrogen and ammonium nitrogen content also showed a decreasing trend. 展开更多
关键词 Lingao County Coastal platform Different forest types Soil physical and chemical properties COMPARISON
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Studies of Soil Physical Properties and Community Characteristics of Different Abandoned Lands in the Minqin Oasis,Downstream of the Shiyang River
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作者 郭春秀 何芳兰 +6 位作者 马剑平 安富博 马俊梅 袁宏波 赵鹏 刘克彪 申国峰 《Agricultural Science & Technology》 CAS 2016年第7期1697-1701,共5页
[Objective] The aim was to explore physical properties and community characteristics of abandoned lands in different years in Minqin Oasis, downstream of the Shiyang River, [Method] The evolution of environment and pl... [Objective] The aim was to explore physical properties and community characteristics of abandoned lands in different years in Minqin Oasis, downstream of the Shiyang River, [Method] The evolution of environment and plant community characteristics in different abandoned lands were analyzed after abandonment for 1, 2, 3, 4, 5, 8, 15, 24 and 31 years, and the plant community characteristics, water content, bulk density, porosity and mechanical composition of soil in the different a- bandoned lands were also researched in the Minqin Oasis, downstream of the Shiyang River. [Result] Plant of 32 species spread over 14 family live through fifty years appeared in abandoned lands in the study area. Shrubs was 6 species, herbs was 26 species among them, which were 18.75%, 81.25% respectively. The goose- foot family (6 species), the composite family(4 species),the grass family(4 species), caltrop family(3 species) were 53.13% among them. Within the range of 0-40 cm of different abandoned Land, the soil moisture content showed a trend of first increase and then decrease with the increase of soil depth changes in soil bulk density and porosity of less obvious. In the range of 0-40 cm soil depth, the largest proportion of fine sand, followed by silt and clay and the smallest proportion of coarse sand in every plot, but the proportion of the each silt size varies little with the years aban- doned. [Conclusion] The research provides references for vegetation reconstruction and eco-environment construction in abandoned lands in downstream of Shiyang River. 展开更多
关键词 Minqin Oasis Abandoned land Years abandoned Soil physical proper- ties Vegetation characteristics
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Analysis of a Class of Logical Functions over Galois and Z_m Rings 被引量:1
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作者 陈卫红 曾洪杰 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第4期105-110,共6页
In this paper, the author analyzed some cryptographic properties of a class of logical functions, f(x,y)=(q(x),...,q(x))·y+h(x),over Galois rings and residue rings, presented the relationship between the characte... In this paper, the author analyzed some cryptographic properties of a class of logical functions, f(x,y)=(q(x),...,q(x))·y+h(x),over Galois rings and residue rings, presented the relationship between the character spectrum of f(x,y) and the character speetrum of q(x),h(x) and the relationship between the cryptographic properties of f(x,y) and the cryptographic properties of h(x). 展开更多
关键词 logical function character spectrum cryptographic properties
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Learning compact binary code based on multiple heterogeneous features
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作者 左欣 罗立民 +1 位作者 沈继锋 于化龙 《Journal of Southeast University(English Edition)》 EI CAS 2013年第4期372-378,共7页
A novel hashing method based on multiple heterogeneous features is proposed to improve the accuracy of the image retrieval system. First, it leverages the imbalanced distribution of the similar and dissimilar samples ... A novel hashing method based on multiple heterogeneous features is proposed to improve the accuracy of the image retrieval system. First, it leverages the imbalanced distribution of the similar and dissimilar samples in the feature space to boost the performance of each weak classifier in the asymmetric boosting framework. Then, the weak classifier based on a novel linear discriminate analysis (LDA) algorithm which is learned from the subspace of heterogeneous features is integrated into the framework. Finally, the proposed method deals with each bit of the code sequentially, which utilizes the samples misclassified in each round in order to learn compact and balanced code. The heterogeneous information from different modalities can be effectively complementary to each other, which leads to much higher performance. The experimental results based on the two public benchmarks demonstrate that this method is superior to many of the state- of-the-art methods. In conclusion, the performance of the retrieval system can be improved with the help of multiple heterogeneous features and the compact hash codes which can be learned by the imbalanced learning method. 展开更多
关键词 hashing code linear discriminate analysis asymmetric boosting heterogeneous feature
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合同纠纷与合同诈骗罪辨析 被引量:4
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作者 吴小军 《华北电力大学学报(社会科学版)》 2006年第3期78-81,共4页
合同纠纷与合同诈骗是两类既相似又本质不同的法律行为。这两者往往容易混淆,不仅在生活中而且在司法实践中也容易引起歧义。因此,对两者进行认真、全面的分析,把握两者的本质属性和具体特征,分清违法与犯罪的区别,以有利于经济交往、... 合同纠纷与合同诈骗是两类既相似又本质不同的法律行为。这两者往往容易混淆,不仅在生活中而且在司法实践中也容易引起歧义。因此,对两者进行认真、全面的分析,把握两者的本质属性和具体特征,分清违法与犯罪的区别,以有利于经济交往、司法活动和法制建设。 展开更多
关键词 合同纠纷 合同诈骗 构成理论 性质:特征
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Effects of micrite microtextures on the elastic and petrophysical properties of carbonate reservoirs 被引量:2
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作者 Pan Jian-Guo Deng Ji-Xin +4 位作者 Li Chuang Wang Hong-Bin Zhang Hu-Quan Zhao Jian-Guo Tang Gen-Yang 《Applied Geophysics》 SCIE CSCD 2019年第4期399-413,559,共16页
Apparent differences in sedimentation and diagenesis exist between carbonate reservoirs in different areas and affect their petrophysical and elastic properties.To elucidate the relevant mechanism,we study and analyze... Apparent differences in sedimentation and diagenesis exist between carbonate reservoirs in different areas and affect their petrophysical and elastic properties.To elucidate the relevant mechanism,we study and analyze the characteristics of rock microstructure and elastic properties of carbonates and their variation regularity using 89 carbonate samples from the different areas The results show that the overall variation regularities of the physical and elastic properties of the carbonate rocks are controlled by the microtextures of the microcrystalline calcite,whereas the traditional classification of rock-and pore-structures is no longer applicable.The micrite microtextures can be divided,with respect to their morphological features,into porous micrite,compact micrite,and tight micrite.As the micrites evolves from the first to the last type,crystal boundaries are observed with increasingly close coalescence,the micritic intercrystalline porosity and pore-throat radius gradually decrease;meanwhile,the rigidity of the calcite microcrystalline particle boundary and elastic homogeneity are enhanced.As a result,the seismic elastic characteristics,such as permeability and velocity of samples,show a general trend of decreasing with the increase of porosity.For low-porosity rock samples(φ<5%)dominated by tight micrite,the micritic pores have limited contributions to porosity and permeability and the micrite elastic properties are similar to those of the rock matrix.In such cases,the macroscopic physical and elastic properties are more susceptible to the formation of cracks and dissolution pores,but these features are controlled by the pore structure.The pore aspect ratio can be used as a good indication of pore types.The bulk modulus aspect ratio for dissolution pores is greater than 0.2,whereas that of the intergranular pores ranges from 0.1 to 0.2.The porous and compact micrites are observed to have a bulk modulus aspect ratio less than 0.1,whereas the ratio of the tight micrite approaches 0.2。 展开更多
关键词 carbonate rock micrite microtextures rock physical properties petrophysical properties pore aspect ratio
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Effect of industrial microwave irradiation on the physicochemical properties and pyrolysis characteristics of lignite 被引量:5
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作者 Guoshun Zhou Qunxing Huang +3 位作者 Ben Yu Hui Tong Yong Chi Jianhua Yan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第5期1171-1178,共8页
The surface functional groups and pyrolysis characteristics of lignite irradiated by microwave were comparatively studied to evaluate the feasibility of using industrial 915 MHz for lignite drying. The drying kinetics... The surface functional groups and pyrolysis characteristics of lignite irradiated by microwave were comparatively studied to evaluate the feasibility of using industrial 915 MHz for lignite drying. The drying kinetics, micro structure, chemical functional groups, re-adsorption properties, and pyrolysis characteristics of the dried coal were respectively analyzed. Results indicated that for typical Chinese lignite studied in this paper, 915 MHz microwave drying was 7.8 times faster than that of the hot air drying. After industrial microwave drying, the sample possessed much higher total specific surface area and specific pore volume than that of air dried sample. The oxygen functional groups and re-adsorption ratio of microwave irradiated coal decreased, showing weakened hydrophilicity. Moreover, during the pyrolysis of the coal dried by hot air and microwave, the yield of tar largely increased from 1.3% to 8.5% and the gas production increased correspondingly. The composition of the tar was also furtherly analyzed, results indicated that Miscellaneous hydrocarbons(HCs) were the main component of the tar, and microwave irradiation can reduce the fraction of polycyclic aromatic hydrocarbons(PAHs) from 26.4% to 22.7%. 展开更多
关键词 LIGNITE Industrial microwave Physicochemical properties Pyrolysis characteristics
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Clinical features of coronary artery ectasia in the elderly 被引量:2
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作者 Qiao-Juan HUANG Yan ZHANG +7 位作者 Xiao-Lin LI Sha LI Yuan-Lin GUO Cheng-Gang ZHU Rui-Xia XU Li-Xin JIANG Meng-Hua CHEN Jian-Jun LI 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2014年第3期185-191,共7页
Objective To investigate the incidence, imaging and clinical characteristics in elderly patients with coronary artery ectasia (CAE). Methods A retrospective analysis was conducted on patients with CAE who underwent ... Objective To investigate the incidence, imaging and clinical characteristics in elderly patients with coronary artery ectasia (CAE). Methods A retrospective analysis was conducted on patients with CAE who underwent coronary angiography between January 2006 and December 2012. According to age, the enrolled patients were divided into two groups (elderly group, age≥ 65 years; non-elderly group, age 〈 65 years). The clinical feature, imaging characteristics and the 5-year survival rate of the two groups were compared.Results The preva-lence of CAE in elderly patients was 0.33%. Patients in elderly group were found to have significantly higher proportion of female (30.1%vs. 10.1%,P〈 0.001), three-vessel disease (60.5%vs. 45.2%,P = 0.003) and localized ectasia (55.0%vs. 40.2%,P = 0.003). In addition, body mass index (20.90 ± 2.71 kg/m2vs. 22.31 ± 2.98 kg/m2,P 〈 0.001) and percentage of current smokers (45.0%vs. 64.6%,P 〈 0.001) were significantly lower in elderly group. Cumulative survival curves demonstrated reduced 5-year cumulative survival at the follow-up in the elderly group compared with the non-elderly group (88.0%vs. 96.0%,P = 0.002). But the 5-year event free survival rate failed to show a significant difference between the two groups (31.0%vs. 35.0%,P= 0.311).ConclusionThe prevalence of CAE in elderly patients was 0.33%, which was about 1/3 of the entire numbers of CAE patients. There were significant differences between the elderly and the non-elderly patients with CAE in terms of coronary artery disease risk factors and coronary artery ectatic characteristics. CAE might be asso-ciated with increased mortality risk in the elderly. 展开更多
关键词 Coronary artery ectasia Elderly patients Clinical feature
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Analysis of the psychological conditions and related factors of breast cancer patients 被引量:4
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作者 Guilin Huang Yiping Wu +2 位作者 Guiqing Zhang Pinghua Zhang Jie Gao 《The Chinese-German Journal of Clinical Oncology》 CAS 2010年第1期53-57,共5页
Sufferers of breast cancer are often plagued by various psychological problems. Mastectomy, which has a serious influence on the female sex characteristics, can bring about especially serious psychological problems. T... Sufferers of breast cancer are often plagued by various psychological problems. Mastectomy, which has a serious influence on the female sex characteristics, can bring about especially serious psychological problems. These problems affect not only the patients’ quality of life but also the beginning, development, and end of the disease. This paper reviewed the relationships between the patients’ personal factors, the disease itself, treatment factors, and other socio-psychological factors and psychological conditions so as to provide new ideas for the psychological intervention on breast cancer patients, comprehensive clinical diagnosis and treatment, and prevention and cure. 展开更多
关键词 breast cancer psychological conditions related factors
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Vegetation Traits and Soil Properties in Response to Utilization Patterns of Grassland in Hulun Buir City, Inner Mongolia, China 被引量:16
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作者 LIU Miao LIU Guohua +2 位作者 WU Xing WANG Hao CHEN Li 《Chinese Geographical Science》 SCIE CSCD 2014年第4期471-478,共8页
Numerous studies have focused on vegetation traits and soil properties in grassland, few of which concerned about effects of human utilization patterns on grassland yet. Thus, this study hypothesized that human distur... Numerous studies have focused on vegetation traits and soil properties in grassland, few of which concerned about effects of human utilization patterns on grassland yet. Thus, this study hypothesized that human disturbance(e.g., grazing, mowing and fencing) triggered significant variation of biomass partitioning and carbon reallocation. Besides, there existed some differences of species diversity and soil fertility. To address these hypotheses of grassland with diverse utilization patterns in Hulun Buir City, Inner Mongolia, China, we sampled in situ about aboveground biomass(AGB) and belowground biomass(BGB) to evaluate their biomass allocation. Species diversity and soil properties were also investigated. Subsequently, we discussed the relationship of species diversity with environmental conditions, using data collected from 23 sites during the ecological project period of Returning Grazing Lands to Grasslands(RGLG) program. The results were as follows: 1) both AGB and BGB were lower on grazing regime than those on fencing and mowing, but the ratio of root-to-shoot(R/S) was higher on grazing regime than the other two utilization patterns; 2) neither of evenness and Simpson Index was different significantly among all grassland utilization patterns in desert, typical, and meadow grassland at 0.05. In meadow grassland, species richness of fencing pattern was significantly higher than that of grazing pattern(p < 0.05); 3) both of soil organic carbon content and soil available phosphorous content were increased significantly on fencing pattern than grazing pattern(p < 0.05) in desert grassland, and mowing patterns increased the soil nutrients(soil organic carbon, soil total phosphorous, soil available phosphorous, and soil total nitrogen) significantly compared with grazing patterns(p < 0.05) in typical grassland. However, there were no significant differences among utilization patterns in meadow grassland. In conclusion, both of AGB and BGB were increased significantly by fencing. Moreover, species diversity and soil nutrients can be promoted via mowing and fencing. This study suggested that implementation of Ecological Project played a positive role in sustainable grassland utilization of Hulun Buir City and a strong positive influence on the entire temperate grassland. 展开更多
关键词 grassland utilization pattems biomass allocation species diversity soil properties temperate grassland Hulun Buir City
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Characteristics of Fin Baffle Packing Used in Rotating Packed Bed 被引量:23
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作者 栗秀萍 刘有智 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第1期55-60,共6页
For an alcohol/water system and with fin baffle packing,continuous distillation experiments were carried out in a rotating packed bed(RPB)system at atmospheric pressure.The effects of the average high gravity factor(... For an alcohol/water system and with fin baffle packing,continuous distillation experiments were carried out in a rotating packed bed(RPB)system at atmospheric pressure.The effects of the average high gravity factor(β),liquid reflux ratio(R)and feedstock flux(F)on the momentum transfer and mass transfer were investigated. The gas phase pressure drop of RPB increased with the average high gravity factor,liquid reflux ratio and feedstock flux,which was 13.55-64.37 Pa atβof 2.01-51.49,R of 1.0-2.5,and F of 8-24 L·h1for a theoretical tray in the RPB with fin baffle packing.The investigation on the mass transfer in the RPB with different packings showed that the number of transfer units of RPB with a packing also increased with the average high gravity factor,reflux ratio and feedstock flux.It is found that the fin baffle packing(packing III)presents the best mass transfer performance and lowest pressure drop for the height equivalent to a theoretical plate(HETP),which is 6.59-9.84 mm. 展开更多
关键词 CHARACTERISTIC fin baffle packing DISTILLATION rotating packed bed
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Effects of Normalized Difference Vegetation Index and Related Wavebands′ Characteristics on Detecting Spatial Heterogeneity Using Variogram-based Analysis 被引量:4
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作者 WEN Zhaofei ZHANG Ce +5 位作者 ZHANG Shuqing DING Changhong LIU Chunyue PAN Xin LI Huapeng SUN Yan 《Chinese Geographical Science》 SCIE CSCD 2012年第2期188-195,共8页
Spatial heterogeneity is widely used in diverse applications, such as recognizing ecological process, guiding ecological restoration, managing land use, etc. Many researches have focused on the inherent scale multipli... Spatial heterogeneity is widely used in diverse applications, such as recognizing ecological process, guiding ecological restoration, managing land use, etc. Many researches have focused on the inherent scale multiplicity of spatial heterogeneity by using various environmental variables. How these variables affect their corresponding spatial heterogeneities, however, have received little attention. In this paper, we examined the effects of characteristics of normalized difference vegetation index (NDVI) and its related bands variable images, namely red and near infrared (NIR), on their corresponding spatial heterogeneity detection based on variogram models. In a coastal wetland region, two groups of study sites with distinct fractal vegetation cover were tested and analyzed. The results show that: l) in high fractal vegetation cover (H-FVC) area, NDV! and NIR variables display a similar ability in detecting the spatial he- terogeneity caused by vegetation growing status structure; 2) in low fractal vegetation cover (L-FVC) area, the NIR and red variables outperform NDVI in the survey of soil spatial heterogeneity; and 3) generally, NIR variable is ubiquitously applicable for vegetation spatial heterogeneity investigation in different fractal vegetation covers. Moreover, as variable selection for remote sensing applications should fully take the characteristics of variables and the study object into account, the proposed variogram analysis method can make the variable selection objectively and scientifically, especially in studies related to spatial heterogeneity using remotely sensed data. 展开更多
关键词 spatial variation spatial structure NDVI characteristic semivariogram model semivariogram analysis
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Rapeseed Breeding for Quality Character in Hunan Province 被引量:1
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作者 Guan Chunyun Li Sun (Department of Agronomy, Hunan Agricultural University, Changsha, China, 410128) 《Hunan Agricultural Science & Technology Newsletter》 2000年第3期12-13,共2页
Eight single-low or double-low rapeseed cultivars were bred from 1980 to 2000 in Hunan Province. In this paper, characters and breeding method of these cultivars are introduced.
关键词 Rapeseed Breeding for quality improvement Transgenic rapeseed line
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Value of Multi-slice spiral CT in diagnosis of malignant gastrointestinal stromal tumors 被引量:5
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作者 Zhongheng He Fajin Lv +1 位作者 Zhaofei Cao Mingxia Qian 《The Chinese-German Journal of Clinical Oncology》 CAS 2009年第8期443-446,共4页
Objective: The aim of this study was to investigate the value of multi-slice spiral CT (MSCT) in the diagnosis of malignant gastrointestinal stromal tumors (GISTs). Methods: Twenty-seven cases of MSCT images of ... Objective: The aim of this study was to investigate the value of multi-slice spiral CT (MSCT) in the diagnosis of malignant gastrointestinal stromal tumors (GISTs). Methods: Twenty-seven cases of MSCT images of malignant GIST proved by surgery and pathology were retrospectively analyzed. Both plain and enhanced CT scan was performed and multiplanar reconstruction was made in all cases. Results: The lesions originated from the stomach (n = 11), small intestine (n = 9), colon (n = 4), rectum (n = 1), and mesentery (n = 2). The transverse diameters of mass were 4.2-22 cm, the edges clearly (n = 12), unclearly (n = 15). The mass were mainly irregular in shape Iobulated (n = 19). The lesions were mainly heterogeneity on plain scan, moderate to marked enhancement in arterial phase and durative enhanced in venous phase. Cystic necrosis were observed in all the lesions, 9 cases were cystic and solid mixed mass. Hepatic metastases (n = 4), pulmonary metastasis (n = 1), lymphatic metastasis (n = 2) were detected. The accuracy rate of MSCT diagnosis for location and pathologic features of GISTs were 85.2% (23/27) and 77.8% (21/27). Conclusion: Two-phase MSCT examination and axial images combined with multiplanar reconstruction images have important value for diagnosis of malignant GIST. 展开更多
关键词 gastrointestinal tract stromal tumor tomography X-ray computed multiplanar reconstruction
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Investigation of Structural System Safety
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作者 Cemal Eyyubov Mehmet Hasnalbant Isa Eyyubov 《Journal of Civil Engineering and Architecture》 2018年第8期586-604,共19页
In order to investigate the behavior of buildings and engineering structures during earthquakes, based on the data of seismic observation devices mounted on constructions with typical characteristics, results of inves... In order to investigate the behavior of buildings and engineering structures during earthquakes, based on the data of seismic observation devices mounted on constructions with typical characteristics, results of investigating the change of mechanical properties of building structural system over time and the results of examination of structural rigidity and safety change over time, depending on the dynamic characteristics of the building, determined by experimental investigations made at intervals are mentioned in this article. In addition, evaluation of earthquake acceleration acting on structures due to earthquake-induced damage characteristics of buildings and engineering constructions which are made earthquake resistant is also included here. 展开更多
关键词 Earthquake intensity macro seismic investigation structural system safety RIGIDITY ground acceleration.
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China's Industries in the Beginning of Its 12th Five-Year Plan Period
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作者 金碚 《China Economist》 2012年第6期4-18,共15页
Complex international and domestic economic scenarios and the short cyclical nature of macroeconomic policies characterizes the beginning year of the 12th Five- Year Plan period, it reflects the difficult policy choic... Complex international and domestic economic scenarios and the short cyclical nature of macroeconomic policies characterizes the beginning year of the 12th Five- Year Plan period, it reflects the difficult policy choices that arise among three major regulatory targets ,for growth, structure, and prices. In the transitional period of intertwined challenges, a spirit of commitment and dedication to real industries will allow China to occupy vantage points in world manufacturing and become an industrial power in the real sense. To a certain extent the beginning year of the 12th Five-Year Plan period (2011-2015), while.fraught with challenges and pain, marks a departure from cutthroat competition to quality growth for Chinese enterprises and entrepreneurs. From 2012, China's industrial and market economic systems will both head towards more sophisticated stages of development. China "s industries will develop along environmentally sustainable, delicate, high-end, IT-based and service-oriented paths, while expediting the country's economic restructuring, industrial upgrade capabilities and its pursuit of innovative industrialization, and it will do so with strides more remarkable than ever before in its history. 展开更多
关键词 12th Five-Year Plan new approach of industrialization industrial transformation and upgrade
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Elementary Research on Activity Behavior of the Crust in Funan-Huoqiu Area, Southern Border of the North China Active Block Region
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作者 Yao Daquan Liu Jiacan 《Earthquake Research in China》 2005年第4期371-380,共10页
The Funan-Huoqiu area is located in the border tectonic belt between the North China and South China active block regions. By means of seismological and geological surveys and synthetic analysis, evidences of tectonic... The Funan-Huoqiu area is located in the border tectonic belt between the North China and South China active block regions. By means of seismological and geological surveys and synthetic analysis, evidences of tectonic deformation in lower intensity have been found in the area since Late Pleistocene, where small earthquakes are distributed linearly along the main faults, conjugate shear joints are developed in the Upper Pleistocene nearby the faults. In the south of the studied region, fissures with different lengths, widths and directions occurred successively in Gushi, Huoqiu, Funan and other places of the area, in the 1970’s, and the direction of the fissures is approximately consistent with that of the Feizhong fault and Wanglaorenji fault. The authors hold that the clustering of small earthquakes, the conjugate shear joints developed in the Upper Pleistocene, the crumpled deformation of materials on fault plane, and the development of modern surface fissures in the area all reflect that the energy in the crust was slowly released, and that the weak deformation took place in corresponding faults. There was only one destructive earthquake taking place in the area (the Jiangkouji {M_S43/4} earthquake). Altogather, there has been weak activity in the area since the Late Quaternary, and it is mainly shown as a creep-slip. 展开更多
关键词 North China Active block region Funan- Huoqiu Activity behavior Activity level
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Reservoir lithology stochastic simulation based on Markov random fields 被引量:2
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作者 梁玉汝 王志忠 郭建华 《Journal of Central South University》 SCIE EI CAS 2014年第9期3610-3616,共7页
Markov random fields(MRF) have potential for predicting and simulating petroleum reservoir facies more accurately from sample data such as logging, core data and seismic data because they can incorporate interclass re... Markov random fields(MRF) have potential for predicting and simulating petroleum reservoir facies more accurately from sample data such as logging, core data and seismic data because they can incorporate interclass relationships. While, many relative studies were based on Markov chain, not MRF, and using Markov chain model for 3D reservoir stochastic simulation has always been the difficulty in reservoir stochastic simulation. MRF was proposed to simulate type variables(for example lithofacies) in this work. Firstly, a Gibbs distribution was proposed to characterize reservoir heterogeneity for building 3-D(three-dimensional) MRF. Secondly, maximum likelihood approaches of model parameters on well data and training image were considered. Compared with the simulation results of MC(Markov chain), the MRF can better reflect the spatial distribution characteristics of sand body. 展开更多
关键词 stochastic modeling Markov random fields training image Monte Carlo simulation
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