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Analysis of genotype differences of rice response to low Zn^(2+) activity and some morphological characteristics 被引量:5
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作者 WANG Renmin, Dept of Agro YANG Xiao’e and YANG Yuai, Dept of Agri Chemistry, ZheJiang Agri Univ, Hangzhou 310029, China 《Chinese Rice Research Newsletter》 1998年第3期11-12,共2页
Zinc deficiency is one of the most widespreadmicro-nutritional disorder for rice. To solve the problem, screening Zn-efficient cultivars isan available method and understanding geno-
关键词 analysis of genotype differences of rice response to low Zn activity and some morphological characteristics root
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Did the one-child policy accelerate gender equality in China?A cross-country difference-in-differences analysis
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作者 Zhenhuan Fang Guang Guo 《China Population and Development Studies》 2024年第2期112-139,共28页
Classic feminist theories have long emphasized high fertility as the main cause of gender inequality and predict that a significant reduction in fertility would lead to reduced gender inequality.In this project,we inv... Classic feminist theories have long emphasized high fertility as the main cause of gender inequality and predict that a significant reduction in fertility would lead to reduced gender inequality.In this project,we investigate whether the one-child pol-icy accelerated gender equality in China.We measure gender inequality by Gender Development Index(GDI),Gender Inequality Index(GII),maternal mortality ratio,and infant mortality rate at the national level from China and five populous middle-income countries in an analysis of difference in differences(DiD).A cross-country DiD sets up a framework in which China with the treatment of the one-child policy could be compared with the control countries without the treatment of the policy.Our analysis shows that China lowered GII by additional 20%,maternal mortality ratio by additional 10%and infant mortality rate by additional 6%relative to the five comparison countries during the period of the one-child policy. 展开更多
关键词 Gender equality FERTILITY One child policy Gender inequality index Difference in defferences analysis Cross-country analysis
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Analysis of differences between anatomic and CT measurements for anterior axial pedicle screw placement
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作者 郑轶Postgraduate School Southern Med Univ 《外科研究与新技术》 2011年第2期85-85,共1页
Objective To explore the differences between anatomic and CT measurements for anterior transoral axial pedicle screw placement. Methods C2 vertebrae of 60 adult spines were measured anatomically,while 20 adult spine v... Objective To explore the differences between anatomic and CT measurements for anterior transoral axial pedicle screw placement. Methods C2 vertebrae of 60 adult spines were measured anatomically,while 20 adult spine vertebrae were 展开更多
关键词 CT analysis of differences between anatomic and CT measurements for anterior axial pedicle screw placement
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An Analysis of the Difference between the Multiple Linear Regression Approach and the Multimodel Ensemble Mean 被引量:5
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作者 柯宗建 董文杰 +2 位作者 张培群 王瑾 赵天保 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第6期1157-1168,共12页
An investigation of the difference in seasonal precipitation forecast skills between the multiple linear regression (MLR) ensemble and the simple multimodel ensemble mean (EM) was based on the forecast quality of ... An investigation of the difference in seasonal precipitation forecast skills between the multiple linear regression (MLR) ensemble and the simple multimodel ensemble mean (EM) was based on the forecast quality of individual models. The possible causes of difference in previous studies were analyzed. In order to make the simulation capability of studied regions relatively uniform, three regions with different temporal correlation coefficients were chosen for this study. Results show the causes resulting in the incapability of the MLR approach vary among different regions. In the Nifio3.4 region, strong co-linearity within individual models is generally the main reason. However, in the high latitude region, no significant co-linearity can be found in individual models, but the abilities of single models are so poor that it makes the MLR approach inappropriate for superensemble forecasts in this region. In addition, it is important to note that the use of various score measurements could result in some discrepancies when we compare the results derived from different multimodel ensemble approaches. 展开更多
关键词 PRECIPITATION multimodel ensemble seasonal prediction difference analysis co-linearity diagnosis
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Rapid recognition of Chinese herbal pieces of Areca catechu by different concocted processes using Fourier transform mid-infrared and near-infrared spectroscopy combined with partial least-squares discriminant analysis 被引量:12
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作者 Hai-Yan Fu Dong-Chen Huang +2 位作者 Tian-Ming Yang Yuan-Bin She Hao Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第7期639-642,共4页
Rapid and sensitive recognition of herbal pieces according to different concocted processing is crucial to quality control and pharmaceutical effect. Near-infrared (NIR) and mid-infrared (MIR) technology combined ... Rapid and sensitive recognition of herbal pieces according to different concocted processing is crucial to quality control and pharmaceutical effect. Near-infrared (NIR) and mid-infrared (MIR) technology combined with supervised pattern recognition based on partial least-squares discriminant analysis (PLSDA) was attempted to classify and recognize six different concocted processing pieces of 600 Areca catechu L. samples and the influence of fingerprint information preprocessing methods on recognition performance was also investigated in this work. Recognition rates of 99.24%, 100% and 99.49% for original fingerprint, multiple scatter correct (MSC) fingerprint and second derivative (2nd derivative) fingerprint of NIR spectra were achieved by PLSDA models, respectively. Meanwhile, a perfect recognition rate of 100% was obtained for the above three fingerprint models of MIR spectra. In conclusion, PLSDA can rapidly and effectively extract otherness of fingerprint information from NIR and MIR spectra to identify different concocted herbal pieces ofA. catechu. 展开更多
关键词 NIR and MIR spectroscopy Partial least-squares discriminant analysis Different concocted processing herbal pieces
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Isolation and bioinformatics analysis of differentially methylated genomic fragments in human gastric cancer 被引量:1
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作者 Ai-Jun Liao Qi Su +2 位作者 Xun Wang Bin Zeng Wei Shi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第9期1333-1338,共6页
AIM:To isolate and analyze the DNA sequences which are methylated differentially between gastric cancer and normal gastric mucosa. METHODS: The differentially methylated DNA sequences between gastric cancer and normal... AIM:To isolate and analyze the DNA sequences which are methylated differentially between gastric cancer and normal gastric mucosa. METHODS: The differentially methylated DNA sequences between gastric cancer and normal gastric mucosa were isolated by methylation-sensitive representational difference analysis (MS-RDA). Similarities between the separated fragments and the human genomic DNA were analyzed with Basic Local Alignment Search Tool (BLAST). RESULTS: Three differentially methylated DNA sequences were obtained, two of which have been accepted by GenBank. The accession numbers are AY887106 and AY887107. AY887107 was highly similar to the 11th exon of LOC440683 (98%), 3' end of LOC440887 (99%), and promoter and exon regions of DRD5 (94%). AY887106 was consistent (98%) with a CpG island in ribosomal RNA isolated from colorectal cancer by Minoru Toyota in 1999. CONCLUSION: The methylation degree is different between gastric cancer and normal gastric mucosa. The differentially methylated DNA sequences can be isolated effectively by MS-RDA. 展开更多
关键词 Gastric cancer DNA methylation Differentia sequences Methylation-sensitive representationa difference analysis
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DYNAMIC BEHAVIOR ANALYSIS FOR LANDING-GEAR WITH DIFFERENT TYPES OF DUAL-CHAMBER SHOCK-STRUTS 被引量:10
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作者 Nie Hong Qiao Xin +1 位作者 Gao Zejun Zhou Lanqin 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1991年第2期235-244,共10页
In this paper three types of dual- chamber shock- struts are considered in dynamic analyses of landing-gear behavior during impact and taxi. Their dynamic characteristics are compared with each other according to calc... In this paper three types of dual- chamber shock- struts are considered in dynamic analyses of landing-gear behavior during impact and taxi. Their dynamic characteristics are compared with each other according to calculation results, and some conclusions are presented.It is very helpful for selecting a suitable type of dual-chamber shock-strut in landing-gear design. 展开更多
关键词 DYNAMIC BEHAVIOR analysis FOR LANDING-GEAR WITH DIFFERENT TYPES OF DUAL-CHAMBER SHOCK-STRUTS
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The difference analysis of physical-mechanical properties of sediments in the central South Yellow Sea and Zhe-Min coastal area in China 被引量:1
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作者 XU Yuanqin LI Ping +4 位作者 LI Peiying DU Jun LIU Lejun GAO Wei LIU Jie 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第7期77-85,共9页
The difference analysis of physical-mechanical properties of muddy sediments is made in the central South Yellow Sea and the Zhe-Min(Zhejiang Province to Fujian Province of China) coastal area. The results show that... The difference analysis of physical-mechanical properties of muddy sediments is made in the central South Yellow Sea and the Zhe-Min(Zhejiang Province to Fujian Province of China) coastal area. The results show that sediments in the two regions are both dominated by mud. There are perfect negative power function correlations between the water content and the density, the compression coefficient and the compression modulus; a good positive power function correlation between the liquid limit and the plastic limit, a perfect positive linear correlation between the water content and the void ratio, and a perfect polynomial function correlation between the miniature vane shear strength and the pocket penetration resistance. In general, compared with sediments in the Zhe-Min coastal area, sediments in the central South Yellow Sea possess high water content, high void ratio,low density, high plasticity, high compressibility, low shear strength. The causes of the differences between physical-mechanical properties of sediments are analyzed from the topographic features, material sources,hydrodynamic conditions, deposition rate, and material composition. Compared with the Zhe-Min coastal area,the central South Yellow Sea is far from the Mainland and low-lying; has poor hydrodynamic condition; the materials diffused to the area are less and dominated by fine clay, have the high content of smectite and organic matters. These factors lead to sediments of the central South Yellow Sea has the higher water content, the higher plasticity, the lower density, and the lower strength than sediments in the Zhe-Min coastal area. 展开更多
关键词 sediment Zhe-Min coastal area central South Yellow Sea physical-mechanical properties difference analysis
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Analysis of different sub-carrier allocation of M-ary QAM-OFDM downlink in RoF system 被引量:1
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作者 邵宇丰 陈烙 +3 位作者 王安蓉 赵云杰 龙颖 季幸平 《Optoelectronics Letters》 EI 2018年第1期40-43,共4页
In this paper, the performance of a 60 GHz radio over fiber(Ro F) system with 4/16/64 quadrature amplitude modulation(QAM) orthogonal frequency division multiplexing(OFDM) downstream signals is studied. Delivery of 10... In this paper, the performance of a 60 GHz radio over fiber(Ro F) system with 4/16/64 quadrature amplitude modulation(QAM) orthogonal frequency division multiplexing(OFDM) downstream signals is studied. Delivery of 10 Gbit/s M-ary QAM(MQAM) OFDM signals through the 20-km-long single-mode fiber(SMF) is complicated in terms of intensity modulation and direct detection(IM/DD). Using self-homodyne method, the beating of two independent light waves generating the millimeter-wave at the photodetector can be down-converted to baseband in the electrical domain. Meanwhile, three kinds of sub-carrier arrangement schemes are compared and discussed, and the simulation results show that lower peak-to-average power ratio(PAPR) can be obtained adopting the adjacent scheme. At bit error rate(BER) of 10^(-3), the receiver sensitivity using 4QAM-OFDM sub-carrier signal is almost enhanced by 4 dB and 9 dB compared with those of 16 QAM-OFDM signal and 64 QAM-OFDM signal. 展开更多
关键词 QAM analysis of different sub-carrier allocation of M-ary QAM-OFDM downlink in RoF system
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Connectivity differences between adult male and female patients with attention deficit hyperactivity disorder according to resting-state functional MRI 被引量:7
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作者 Bo-yong Park Hyunjin Park 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第1期119-125,共7页
Attention deficit hyperactivity disorder(ADHD) is a pervasive psychiatric disorder that affects both children and adults. Adult male and female patients with ADHD are differentially affected, but few studies have ex... Attention deficit hyperactivity disorder(ADHD) is a pervasive psychiatric disorder that affects both children and adults. Adult male and female patients with ADHD are differentially affected, but few studies have explored the differences. The purpose of this study was to quantify differences between adult male and female patients with ADHD based on neuroimaging and connectivity analysis. Resting-state functional magnetic resonance imaging scans were obtained and preprocessed in 82 patients. Group-wise differences between male and female patients were quantified using degree centrality for different brain regions. The medial-, middle-, and inferior-frontal gyrus, superior parietal lobule, precuneus, supramarginal gyrus, superior- and middle-temporal gyrus, middle occipital gyrus, and cuneus were identified as regions with significant group-wise differences. The identified regions were correlated with clinical scores reflecting depression and anxiety and significant correlations were found. Adult ADHD patients exhibit different levels of depression and anxiety depending on sex, and our study provides insight into how changes in brain circuitry might differentially impact male and female ADHD patients. 展开更多
关键词 neural regeneration connectivity attention deficit hyperactivity disorder sex difference functional magnetic resonance imaging depression anxiety network analysis degree centrality diagnostic and statistical manual score
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ANALYSIS OF Lyl1 EXPRESSION AS A FREQUENT PARTNER OF LMO2 IN T-CELL LEUKEMOGENESIS IN HUMAN
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作者 耿东进 黄安尼 +6 位作者 陈军浩 张乐 陈蕾蕾 刘勇 顾香芳 韩鹂 李雷 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2005年第3期184-189,共6页
Objective: To identify aberrant gene expression in primary human T-cell acute lymphoblastic leukemia (T-ALL) and to evaluate the differently expressed level of Lyll and LMO2 genes in human LMO2 positive/TALl negati... Objective: To identify aberrant gene expression in primary human T-cell acute lymphoblastic leukemia (T-ALL) and to evaluate the differently expressed level of Lyll and LMO2 genes in human LMO2 positive/TALl negative T-ALL tumors. Methods: Three methods, representational difference analysis (RDA) of cDNA, cDNA microarrays and RT-PCR were used to detect if Lyll and LMO2 genes were differently expressed in human LMO2 positive/tall negative T-ALL tumors. Results: The results of cDNA RDA and cDNA array shown that Lyll and LMO2 genes are differently expressed in human T-cell tumors. The result of RT-PCR also shown Lyll and LMO2 are high expressed in human T-cell tumors and very low level or no expressed in normal group. Conclusion: We have found that cDNA RDA and cDNA microarray can be successfully used to identify aberrant gene expression in T-ALL cells. In the study described in this manuscript we found that Lyll and LMO2 are aberrantly expressed in human T-ALL LMO2 positive/TALl negative T-ALL tumors. 展开更多
关键词 T-cell leukemogenesis Lyll LMO2 Representational difference analysis (RDA) of cDNA cDNA microarray
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IDENTIFICATION OF DIFFERENTIAL GENES IN OVARIAN CANCER USING REPRESENTATIONAL DIFFERENCE ANALYSIS OF cDNA
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作者 Hong Chen Min Wang +3 位作者 Xin-yan Wang Shan Gao Jun Wang Xiao-ming Guan 《Chinese Medical Sciences Journal》 CAS CSCD 2005年第3期185-189,共5页
Objoctive To identify differential genes between normal ovarian epithelium tissue and ovarian epithelial cancer using representational difference analysis of cDNA (cDNA-RDA). Methods cDNA-RDA was performed to ident... Objoctive To identify differential genes between normal ovarian epithelium tissue and ovarian epithelial cancer using representational difference analysis of cDNA (cDNA-RDA). Methods cDNA-RDA was performed to identify the differentially expressed sequences between cDNAs from cancer tissue and cDNAs from normal ovarian tissue in the same patient who was in the early stage of ovarian serous cystadenocarcinoma. These differentially expressed fragments were cloned and analyzed, then sequenced and compared with known genes. Results Three differentially cxpressed cDNA fragments were isolated using cDNA from normal ovarian tissue as tester and cDNA from cancer tissue as driver amplicon by cDNA-RDA. DP Ⅲ- 1 and DP Ⅲ-2 cDNA clone showed significant homology to the cDNA of alpha actin gene; DPⅢ-3 cDNA clone showed significant homology to the cDNA oftransgelin gene. Conclusion cDNA-RDA can bc used to sensitively identify the differentially expressed genes in ovarian serous cystadenocarcinoma. Ovarian serous cystadenocarcinoma involves alteration of multiple genes. 展开更多
关键词 representational difference analysis of cDNA ovarian cancer differential expressed gene tumor suppressive gene
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Clinical analysis of different periods of liver transplantation at an organ transplantation centre
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作者 梁廷波 《外科研究与新技术》 2003年第2期129-130,共2页
Objective To summarize our clinical experience in liver transplantation while considering the background in this filed in China. Methods Ninety-five patients who had received liver transplantation from April 1993 to M... Objective To summarize our clinical experience in liver transplantation while considering the background in this filed in China. Methods Ninety-five patients who had received liver transplantation from April 1993 to March 2002 were analyzed retrospectively. Three periods were defined objectively as period Ⅰ(1993-1997),Ⅱ(1999) and Ⅲ(2000 -2002). Operative techniques, recipients, original diseases, complications and survival rates were compared among the three periods. Results Malignant liver lesions were the main cause for liver transplantation in period Ⅰ and Ⅱ. The ratio of number of malignant disease to total recipients decreased gradually from period Ⅰ to Ⅱ (100%, 53% and 35%, respectively). The 1-year survival rate in patients with benign liver disease was 85 % and the total operative mortality was 5% in period Ⅲ. The incidence of hepatitis B virus reactivation or reinfection was 24% twelve months after liver transplantation. Vascular complication decreased but biliary complications did 展开更多
关键词 of Clinical analysis of different periods of liver transplantation at an organ transplantation centre
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三角恒等变换中的六类创新问题
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作者 冷文华 《中学生数理化(高一数学)》 2025年第12期40-41,M0002,共3页
创新1:三角恒等变换中的“差异分析法”例1计算:3/sin^(2)20°-1/cos^(2)20°+64sin^(2)20°=____。解析:3/sin^(2)20°-1/cos^(2)20°+64sin^(2)20°=3sin^(2)20°-sin^(2)20°/sin^(2)20°·... 创新1:三角恒等变换中的“差异分析法”例1计算:3/sin^(2)20°-1/cos^(2)20°+64sin^(2)20°=____。解析:3/sin^(2)20°-1/cos^(2)20°+64sin^(2)20°=3sin^(2)20°-sin^(2)20°/sin^(2)20°·cos^(2)20°+64sin^(2)20°=(√3cos^(2)20°-sin^(2)20°)(√3cos^(2)20°+sin^(2)20°)/sin^(2)20°·cos^(2)20°+32-32cos^(2)40°=4cos50°sin80°/1/4sin^(2)40°+32-32cos 40°+32-32cos40°=32。 展开更多
关键词 innovative problem solving difference analysis method triangle identity transformation
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Metastatic suppressor genes inactivated by aberrant methylation in gastric cancer 被引量:7
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作者 Jian-Feng Wang Dong-Qiu Dai 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第43期5692-5698,共7页
AIM: To screen out the differentially methylated DNA sequences between gastric primary tumor and metastatic lymph nodes, test the methylation difference of gene PTPRG between primary gastric tumor and metastatic lymph... AIM: To screen out the differentially methylated DNA sequences between gastric primary tumor and metastatic lymph nodes, test the methylation difference of gene PTPRG between primary gastric tumor and metastatic lymph nodes, and test the regulatory function of 5-aza- 2-deoxycytidine which is an agent with suppression on methylation and the level of methylation in gastric cancer cell line. METHODS: Methylated DNA sequences in genome were enriched with methylated CpG islands amplification (MCA) to undergo representational difference analysis (RDA), with MCA production of metastatic lymph nodes as tester and that of primary tumor as driver. The obtained differentially methylated fragments were cloned and sequenced to acquire the base sequence, which was analyzed with bioinformatics. With methylation-specific PCR (MSP) and RT-PCR, methylation difference of gene PTPRG was detected between primary tumor and metastatic lymph nodes in 36 cases of gastric cancer. Methylation of gene PTPRG and its regulated expression were observed in gastric cancer cell line before and after being treated with methylation-suppressive agent. RESULTS: Nineteen differentially methylated sequences were obtained and located at 5' end, exons, introns and 3' end, in which KL59 was observed to be located at 9p21 as the first exon of gene p16 and KL22 to be located at promoter region of PRPRG . KL22, as the probes, was hybridized with driver, tester and 3-round RDA products respectively with all positive signals except with the driver. Significant difference was observed in both methylation rate of gene PTPRG and PTPRG mRNA expression rate between primary tumor and metastatic lymph nodes. Demethylation of gene PTPRG, with recovered expression of PTPRG mRNA, was observed after gastric cancer cell line being treated with methylation-suppressive agent. CONCLUSION: Difference exists in DNA methylation between primary tumor and metastatic lymph nodes of gastric cancer, with MCA-RDA as one of the good analytical methods. Significant difference exists in methylation of gene PTPRG between primary tumor and metastatic lymph nodes of gastric cancer. Methylation level in gastric cancer cell line can be decreased by 5-aza-2'-deoxycytidine, which is the methylation- suppressive agent, with PTPRG expression being recovered. 展开更多
关键词 Gastric cancer Methylated CpG islandsamplification Representational difference analysis DNA methylation gene PTPRG
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Spatial-temporal Changes of Vegetation Cover in Guizhou Province, Southern China 被引量:26
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作者 TIAN Yichao BAI Xiaoyong +2 位作者 WANG Shijie QIN Luoyi LI Yue 《Chinese Geographical Science》 SCIE CSCD 2017年第1期25-38,共14页
Guizhou Province is an important karst area in the world and a fragile ecological area in China. Ecological risk assessment is very necessary to be conducted in this region. This study investigates different character... Guizhou Province is an important karst area in the world and a fragile ecological area in China. Ecological risk assessment is very necessary to be conducted in this region. This study investigates different characteristics of the spatial-temporal changes of vegetation cover in Guizhou Province of Southern China using the data set of SPOT VEGETATION(1999–2015) at spatial resolution of 1-km and temporal resolution of 10-day. The coefficient of variation, the Theil-Sen median trend analysis, and the Mann-Kendall test are used to investigate the spatial-temporal change of vegetation cover and its future trend. Results show that: 1) the spatial distribution pattern of vegetation cover in Guizhou Plateau is high in the east whereas low in the west. The average annual normalized difference vegetation index(NDVI) from west to east is higher than that from south to north. 2) Average annual NDVI improved obviously in the past 17 years. The growth rate of average annual NDVI is 0.028/10 yr, which is slower than that of vegetation in the country(0.048/10 yr) from 1998 to 2007. Average annual NDVI in karst area is lower than that in non-karst area. However, the growing rate of average annual NDVI in karst area(0.030/10 yr) is faster than that in non-karst area(0.023/10 yr), indicating that vegetation coverage increases more rapidly in karst area. 3) Vegetation coverage in the study area is stable overall, but fluctuates in the local scales. 4) Vegetation coverage presents a continuous increasing trend. The Hurst exponent of NDVI in different vegetation types has an obvious threshold in various elevations. 5) The proportion of vegetation cover with sustainable increase is higher than that of vegetation cover with sustainable decrease. The improvement in vegetation cover may expand to most parts of the study area. 展开更多
关键词 vegetation cover spatial-temporal change trends analysis normalized difference vegetation index(NDVI) Hurst exponent Guizhou Province China
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A new iterative algorithm for geolocating a known altitude target using TDOA and FDOA measurements in the presence of satellite location uncertainty 被引量:27
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作者 Cao Yalu Peng Li +2 位作者 Li Jinzhou Yang Le Guo Fucheng 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2015年第5期1510-1518,共9页
This paper considers the problem of geolocating a target on the Earth surface whose altitude is known previously using the target signal time difference of arrival (TDOA) and frequency difference of arrival (FDOA)... This paper considers the problem of geolocating a target on the Earth surface whose altitude is known previously using the target signal time difference of arrival (TDOA) and frequency difference of arrival (FDOA) measurements obtained at satellites. The number of satellites available for the geolocation task is more than sufficient and their locations are subject to random errors. This paper derives the constrained Cramor-Rao lower bound (CCRLB) of the target position, and on the basis of the CCRLB analysis, an approximately efficient constrained maximum likelihood estimator (CMLE) for geolocating the target is established. A new iterative algorithm for solving the CMLE is then proposed, where the updated target position estimate is shown to be the globally optimal solution to a generalized trust region sub-problem (GTRS) which can be found via a simple bisection search. First-order mean square error (MSE) analysis is conducted to quantify the performance degradation when the known target altitude is assumed to be precise but indeed has an unknown but deterministic error. Computer simulations are used to compare the performance of the proposed iterative geolocation technique with those of two benchmark algorithms. They verify the approximate efficiency of the proposed algorithm and the validity of the MSE analysis. 展开更多
关键词 Constrained Cram6r-Raolower bound (CCRLB):Frequency difference ofarrival (FDOA) Generalized trust regionsub-problem (GTRS):Performance analysis:Time difference of arrival(TDOA)
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A New Dual Polarized Aperture-Coupled Printed Array for SAR Applications 被引量:1
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作者 ZHONG Shun shi, CUI Jun hai Department of Communication and Information Engineering, Shanghai University, Shanghai 200072, China 《Journal of Shanghai University(English Edition)》 CAS 2001年第4期295-298,共4页
This paper presents a new design of dual polarized aperture coupled printed antenna array. The finite difference time domain (FDTD) analysis of an aperture coupled microstrip element is performed, and the effects ... This paper presents a new design of dual polarized aperture coupled printed antenna array. The finite difference time domain (FDTD) analysis of an aperture coupled microstrip element is performed, and the effects of antenna parameters on its characteristics are obtained to guide the design of the printed array. Then an 8×2 dual polarized array design in X band is introduced with configuration plots. In order to improve its isolation and cross polarization, an outphase displacement feeding technique is adopted in the feed network. Also, the round bends are used instead of conventional right angle bends so as to achieve better VSWR performance. Experimental results are presented, indicating the validity of the design. This dual polarized array can be applied as a sub array of spaceborne SAR systems. 展开更多
关键词 microstrip antenna array dual polarization aperture coupled finite difference time domain analysis synthetic aperture radar
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Compositional and Structural Difference of Fulvic Acid from Black Soil Applied with Different Organic Materials: Assessment After Three Years 被引量:3
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作者 LI Jian-ming WU Jing-gui 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第10期1865-1871,共7页
Knowledge of different effects of various organic materials on soil humic substance is important for both environmental safety and sustainable agriculture.A pot experiment was conducted at Jilin Agricultural Universit... Knowledge of different effects of various organic materials on soil humic substance is important for both environmental safety and sustainable agriculture.A pot experiment was conducted at Jilin Agricultural University,Jilin Province in northeast China to discover the influence of herb residue,animal excrement,woody residue,animal remnant on fulvic acid(FA) composition and structure using differential thermal analysis-thermogravimetric(DTA-TG),fourier transform infrared spectroscopy(FTIR) and elemental analysis.DTA-TG showed the range of peak temperature in the first exothermic reaction increased following the trend: CK〉herb residue〉animal excrement〉woody residue=animal remnant,and the most weight loss was observed in animal excrement.Moreover,the second exothermic reaction of CK-and animal excrement-FA was presented as double peaks,the order of weight loss in that area was animal remnant〉CK〉woody residue〉animal excrement〉herb residue.According to FTIR,herb residue displayed higher adsorption intensity at 2 950,1 420,1 240 and 1 030 cm-1,animal excrement was in reverse.At the same time,herb residue-and animal excrement-FA had an absorption peak at 1 720 cm-1,while other organic materials didn't have this peak.As elemental analysis showed,FA isolated from various treatments was significantly distinct.It was clearly shown from our results that FA composition and structure in amended soils may be affected in different ways and at various extents on dependence of the nature and origin of amendment. 展开更多
关键词 different organic materials fulvic acid DTA-TG FTIR elemental analysis
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