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5个微卫星座位与河北荷斯坦母牛乳成分性状关系研究 被引量:2
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作者 储明星 安永福 +1 位作者 方丽 叶素成 《畜牧兽医学报》 CAS CSCD 北大核心 2006年第6期537-543,共7页
选择与奶牛乳成分性状紧密相关的5个微卫星座位BM1818、BM143、BM1443、BM1905、BM711,用非变性聚丙烯酰胺凝胶电泳法分析其在90头河北荷斯坦母牛中的遗传变异。计算了5个微卫星座位的等位基因频率、杂合度、多态信息含量和有效等位基因... 选择与奶牛乳成分性状紧密相关的5个微卫星座位BM1818、BM143、BM1443、BM1905、BM711,用非变性聚丙烯酰胺凝胶电泳法分析其在90头河北荷斯坦母牛中的遗传变异。计算了5个微卫星座位的等位基因频率、杂合度、多态信息含量和有效等位基因数,并利用最小二乘法拟合线性模型初步探索了这5个微卫星座位与河北荷斯坦母牛乳成分性状的关系。结果表明:微卫星座位BM1818对乳干物质率影响显著;微卫星座位BM143和BM711对305 d产奶量、乳脂率、蛋白率和干物质率影响显著;微卫星座位BM1443对305 d产奶量影响显著;微卫星座位BM1905对305 d产奶量、蛋白率影响显著。显著影响305 d产奶量的最有利基因型在BM143座位上为102 bp/120 bp,在BM1443座位上为160 bp/160 bp,在BM1905座位上为182 bp/195 bp,在BM711座位上为182bp/182 bp;显著影响乳脂率的最有利基因型在BM143座位上为100 bp/112 bp,在BM711座位上为173 bp/188bp;显著影响蛋白率的最有利基因型在BM143座位上为120 bp/120 bp,在BM1905座位上为177 bp/189 bp,在BM711座位上为180 bp/188 bp;显著影响牛乳干物质率的最有利基因型在BM1818座位上为278 bp/282 bp,在BM143座位上为100 bp/112 bp,在BM711座位上为173 bp/190 bp。 展开更多
关键词 荷斯坦母牛 成分性状 微卫星 遗传多态性
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病原侵染早期小麦抗白粉病性状的构成因素剖析和QTL定位分析
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作者 王华忠 章珍 +1 位作者 贺洋 岳洁瑜 《作物学报》 CAS CSCD 北大核心 2011年第7期1219-1228,共10页
以国际小麦作图组织提供的W7984×Opata85重组近交群体为材料,将白粉病抗性分解为互作早期不同时间点的乳突指数、乳突级别、吸器指数和二级菌丝指数等成分性状,在成分性状鉴定和统计的基础上,进行遗传分析和相关QTL定位。白粉菌侵... 以国际小麦作图组织提供的W7984×Opata85重组近交群体为材料,将白粉病抗性分解为互作早期不同时间点的乳突指数、乳突级别、吸器指数和二级菌丝指数等成分性状,在成分性状鉴定和统计的基础上,进行遗传分析和相关QTL定位。白粉菌侵染早期乳突指数和吸器指数随时间的变化趋势均受主效单基因的调控。数量性状分析共找到34个与抗白粉病相关的QTL(21个主效QTL),分布于小麦1B、1D、2B、3A、3B、3D、4A、4B、4D、5B、6A、6B、6D、7B和7D染色体上。位于7B染色体上的QTL(QPmPI16.tn-7B)对乳突形成的影响极为显著,贡献率达48.7%,促进乳突形成的等位变异来自Opata85。不同成分性状存在共定位的QTL。成分性状的特异QTL提供了更多有关抗白粉病遗传机制的信息。 展开更多
关键词 小麦白粉病 侵染早期 成分性状 QTL定位
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Correlation and Principal Component Analysis on Main Agronomic Traits of New Waxy Corn Varieties 被引量:6
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作者 吕莹莹 李特 +3 位作者 张萌 沈丹丹 张士东 张恩盈 《Agricultural Science & Technology》 CAS 2017年第9期1732-1737,共6页
[Objective] This study was conducted to provide certain theoretical reference for the comprehensive evaluation and breeding of new fresh waxy corn vari- eties. [Method] With 5 good fresh waxy corn varieties as experim... [Objective] This study was conducted to provide certain theoretical reference for the comprehensive evaluation and breeding of new fresh waxy corn vari- eties. [Method] With 5 good fresh waxy corn varieties as experimental materials, correlation analysis and principal component anatysis were performed on 13 agronomic traits, i.e., plant height, ear position, ear weight, ear diameter, axis diameter, ear length, bald tip length, ear row number, number of grains per row, 100-kernel weight, fresh ear yield, tassel length, and tassel branch number. [Result] The principal component analysis performed to the 13 agronomic traits showed that the first three principal components, i.e., the fresh ear yield factors, the tassel factors and the bald top factors, had an accumulative contribution rate over 87.2767%, and could basically represent the genetic information represented by the 13 traits. The first principal component is the main index for the selection and evaluation of good corn varieties which should have large ear, large ear diameter but small axis diameter, i.e., longer grains, larger number of grains per ear, higher, 100-grain weight and higher plant height. As to the second principal component, the plants of fresh corn varieties are best to have longer tassel and not too many branches, and under the premise of ensuring enough pollen for the female spike, the varieties with fewer tassel branches shoud be selected as far as possible. From the point of the third principal component, bald tip length affects the marketing quality of fresh corn, and during fariety evaluation and breeding, the bald top length should be control at the Iowest standard. [Conclusion] The fresh ear yield of corn is in close positive correlation with ear weight, 100-grain weight, ear diameter, number of grains per row and ear length, and plant height also affects fresh ear yield. 展开更多
关键词 Waxy corn Fresh ear yield Agronomic traits Principal component analysis Correlation analysis
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多个主成分性状的综合优化研究 被引量:1
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作者 吉俊玲 秦豪荣 袁志发 《生物数学学报》 CSCD 北大核心 2011年第2期377-383,共7页
考虑育种目标的要求,对多个独立的主成分性状进行综合优化,建立了综合主成分性状的数学模型.综合主成分性状是s个表型方差(遗传方差)最大的主成分性状在育种目标约束下表型方差(或遗传方差)极大化下的线性组合,作为育种指标,选择效果好... 考虑育种目标的要求,对多个独立的主成分性状进行综合优化,建立了综合主成分性状的数学模型.综合主成分性状是s个表型方差(遗传方差)最大的主成分性状在育种目标约束下表型方差(或遗传方差)极大化下的线性组合,作为育种指标,选择效果好,预见性强. 展开更多
关键词 成分性状 综合主成分性状 育种目标 选择指数
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Study on Germplasm Resources of Tartary Buckwheat (Fagopyrum tataricum) in Shanxi Province 被引量:1
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作者 张丽君 马名川 +3 位作者 刘龙龙 康国帅 周建萍 崔林 《Agricultural Science & Technology》 CAS 2016年第5期1217-1222,1270,共7页
This study analyzed the tartary buckwheat recorded in the books Catalogue of Crop Germplasm Resources in Shanxi Province and Catalogue of Chinese Buckwheat Germplasm Resources by Excel 2003 and DPS 7.5 from the aspect... This study analyzed the tartary buckwheat recorded in the books Catalogue of Crop Germplasm Resources in Shanxi Province and Catalogue of Chinese Buckwheat Germplasm Resources by Excel 2003 and DPS 7.5 from the aspects of distribution areas,main agronomic traits and nutritional components,so as to lay a foundation for the selection of excellent buckwheat germplasm resources and improvement of buckwheat varieties.The results showed that different buckwheat varieties vary in plant height,node number of the main stem,grain weight per plant,grain weight per plant and kilo-grain weight.Compared with the national average values,buckwheat in Shanxi is higher in protein and fat,but lower in vitamin E and vitamin PP;it is rich in Ca,Mg,Cu,P,Se,Fe,Mn and Zn;and it contains 18 amino acids with the content of glutamic acid being the highest and the content of tryptophane being the lowest.After analyzing and classifying the tartary buckwheat germplasm resources recorded in Catalogue of Grop Germplasm Resources in Shanxi Province and Catalogue of Chinese Buckwheat Germplasm Resources,breeders could breed new varieties with high yield and quality and strong stress resistance by crossbreeding with these germplasm resources. 展开更多
关键词 Tartary buckwheat Agronomic traits Nutritional composition Germplasm resources SHANXI
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Statistic Morphology Difference between Male and Female Individuals of Paramisgurnus dabryanus Sauvage
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作者 安丽 朱永安 +3 位作者 王玉新 郑玉珍 董学飒 刘羽清 《Agricultural Science & Technology》 CAS 2010年第8期114-116,124,共4页
[Objective] The aim was to compare the morphology difference between male and female individuals of Paramisgurnus dabryanus Sauvage. [Method] The comparison of 10 morphological characteristics between male and female ... [Objective] The aim was to compare the morphology difference between male and female individuals of Paramisgurnus dabryanus Sauvage. [Method] The comparison of 10 morphological characteristics between male and female individuals of P. dabryanus was conducted with principal component analysis and t-test methods. [Result] The results of t-test indicated that three of 10 morphological characteristics showed extremely significant difference(P0.01)and one of 10 morphological characteristics was significantly different(P0.05). Principal component analysis revealed four principal components,the contribution rate of which was 31.151%,18.844%,12.324% and 10.169%,respectively. The cumulative contribution rate had reached 72.487%. The morphological variations between male and female individuals were not significant,which was consistent with that of t-test. [Conclusion] The result in this study had provided theoretical basis for the breeding of P. dabryanus. 展开更多
关键词 Paramisgurnus dabryanus Sauvage Morphological trait Principal component analysis T-TEST
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Principal Component Analysis on Traits Related to Lodging Resistance of Plateau Japonica Rice
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作者 丁明亮 浦秋红 +2 位作者 高春琼 袁平荣 苏振喜 《Agricultural Science & Technology》 CAS 2015年第6期1115-1120,共6页
Objective] This study was conducted to investigate the main factors affect-ing the lodging resistance of plateau japonica rice. [Method] Twenty agronomic traits related to lodging resistance of plateau japonica rice w... Objective] This study was conducted to investigate the main factors affect-ing the lodging resistance of plateau japonica rice. [Method] Twenty agronomic traits related to lodging resistance of plateau japonica rice were analyzed by principal component analysis and correlation analysis among 26 varieties/lines of plateau japonica rice. [Result] The lodging resistance of the 26 varieties/lines had great dif-ference among different agronomic traits. Plant height, and wal thickness of the 4th, 3rd and 2nd internodes under the panicle had the most important influence on lodging resistance, while the diameter of the 3rd, 2nd, 4th, 1st nodes under the panicle, length of the 4th and 3rd internodes under the panicle, wal thickness of the 1st internode under the panicle had less influence. The other nine agronomic traits of rice culm did not affect or indirectly affected lodging resistance through above-mentioned agro-nomic traits. Lodging resistance had significant correlations with plant height, length of the 4th and 3rd internodes under the panicle, wal thickness of the 1st, 2nd, 3rd and 4th internodes under the panicle and diameter of the 1st, 2nd, 3rd and 4th node sunder the panicle, had insignificant correlations with panicle length, panicle weight, length of the 1st and 2nd internodes under the panicle, diameter of the 1st, 2nd, 3rd and 4th internodes under the panicle, diameter of the 5th node under the panicle. [Conclu-sion] More attention should be paid to the main factors affecting lodging resistance in breeding to improve lodging resistance of plateau japonica rice. 展开更多
关键词 Plateau japonica rice Lodging resistance Agronomic traits Principal component analysis
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Identification of Quality Characteristics of Sun-cured Tobacco Leaves
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作者 柴家荣 王毅 +4 位作者 谢丽华 屈生彬 张晨东 钱颖颖 董华 《Agricultural Science & Technology》 CAS 2013年第4期577-581,共5页
[Objective] The aim was to explore tobacco varieties which satisfy tobacco formula and is suitable to be grown in ecotopes simultaneously. [Method] Interior and exterior qualities of tobacco were compared and identifi... [Objective] The aim was to explore tobacco varieties which satisfy tobacco formula and is suitable to be grown in ecotopes simultaneously. [Method] Interior and exterior qualities of tobacco were compared and identified based on agronomic and economic characters of tobacco in fields. [Result] Yunshai No.1 was better in both agronomic and economic characters. Specifically, the fragrance was dominated by empyreumatique and aroma; the highly-qualified variety is fragrant and sweet, with little irritation, which gives the tobacco smoke a light, mild flavor. As for Virgini- a934, economic characters were better, but agronomic characters were just ordinary. Similar to Yunshai No.l, dominated by empyreumatique and aroma, the variety was with distinctive resin and herbaceous fragrance. What's more, it tasted good with high quality and usability. Cunsanpi was ordinary in agronomic characters, and poor in economic characters, with coordinated quality and chemical composition. It is fra- grant and the smoke is clean. However, the quality was not so high and it tasted not so good. Tengruan No.2 was good in agronomic characters, but poor in eco- nomic characters, which gives delicate fragrance, but not clean enough. Waiweiba and Mijie Qinggeng neither taste well nor smell sweet, performing ordinary in agro- nomic and economic characters. Hence, the two varieties seem bad in quality and ranks poorly. [Conclusion] In terms of sensory quality, the varieties from high to low were Yunshai No.1, Virginia 934, Cunsanpi, Tengruan No.2, Waiweiba and Mijie Qinggeng. 展开更多
关键词 Variety of sun-cured tobacco Economic characters Appearance and quality Chemical composition Sensory quality
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无公害蔬菜生产的首选—华丰肥土特生物有机肥
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《农家致富》 2003年第1期32-32,共1页
关键词 无公害蔬菜 生产 华丰肥土特 生物有机肥 性能特点 性状成分
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Morphological comparison between a selected fast-growing strain and the common cultured strain of turbot Scophthalmus maximus 被引量:4
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作者 梁兴明 马爱军 +3 位作者 王新安 李娟 黄智慧 商晓梅 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第4期563-568,共6页
To evaluate the effect of genetic improvement of the turbot Scophthalmus maximus, we analyzed morphological differences between a fast-growing strain obtained by family selection and the common cultured strain, by pri... To evaluate the effect of genetic improvement of the turbot Scophthalmus maximus, we analyzed morphological differences between a fast-growing strain obtained by family selection and the common cultured strain, by principal component analysis, stepwise discriminant analysis, and t-tests. Although they clearly differed morphologically, plots of the principal components of the two strains partially overlapped. However, the difference between the strains was supported with very high precision by discriminant analysis. The t-tests revealed that 4 of the 13 morphological traits analyzed were highly significantly different (P<0.01), 4 traits also differed significantly (P<0.05), and the remainder did not differ significantly. The coefficients of difference of the 13 traits were all lower than the threshold value between subspecies (1.28). Together, the results indicate that a trend for segregation of characters from the common cultured strain have already appeared in the selected fast-growing strain but the degree of segregation have not risen to subspecies level. 展开更多
关键词 Scophthalmus maximus divergence by selection quantitative trait analysis
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Comparative Analysis of Morphologic Traits of 50 Large-flowered Chrysanthemum Varieties
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作者 沈珍 毛燕 +2 位作者 吴德智 袁伟 杨旭 《Agricultural Science & Technology》 CAS 2016年第2期317-322,共6页
With 50 large-flowered Chrysanthemum varieties from germplasm nursery of Wunaoshan Forest Farm in Macheng City as research objects, 64 morphological traits were investigated by field experiments adopting randomized bl... With 50 large-flowered Chrysanthemum varieties from germplasm nursery of Wunaoshan Forest Farm in Macheng City as research objects, 64 morphological traits were investigated by field experiments adopting randomized block design. The morphological differences were observed by uniformity analysis, variability analysis, principal component analysis and cluster analysis. The result showed that the vari- able coefficients of 59 traits were greater than 15%; the contribution rate of first seven principal components reached 81.45%; and it was found by clustering analy- sis that the 50 germplasm resources could be divided into four clusters with obvious morphological differences, and plant type could be used as an index for classifica- tion. 展开更多
关键词 Large-flowered Chrysanthemum Morphologic traits Variability analysis Principal component analysis Clustering analysis
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Analysis of F_1 Heterosis of Agronomic Traits and Chemical Components on Selfbred Highpotassium New Lines 被引量:2
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作者 Linjian DAI Zhu PAN Jun ZHONG 《Agricultural Science & Technology》 CAS 2017年第1期27-31,40,共6页
F1 heterosis of agronomic characters and chemical components of 8 fluecured tobacco varieties and 6 self-bred high-potassium new lines was studied. The results showed that 4-5 weeks after transplanting was the main ch... F1 heterosis of agronomic characters and chemical components of 8 fluecured tobacco varieties and 6 self-bred high-potassium new lines was studied. The results showed that 4-5 weeks after transplanting was the main changing period of agronomic traits. Compared with the comparative heterosis, among the proportions of combinations showing positive comparative heterosis at the significant level, the heterosis proportions of plant height (97.92%), internode length (100%) and stem girth (58.33%) were larger, these of total nitrogen (83.33%), protein (79.17%), nicotine (79.17%) and potassium (95.83%) in upper leaves were larger, these of total sugar (64.58%), total nitrogen (68.75%), protein (72.92%) and nicotine (64.58%) in middle leaves were larger, and in lower leaves, except that the proportion of chlorine was smaller (12.50%), the proportions of other chemical components all exceeded 40%. Compared with average heterosis, among the proportions of combinations showing positive comparative heterosis at the significant level, the heterosis proportions of plant height (54.17%), leaf width (43.75%), stem girth (43.75%) and internode length (72.92%) were larger, these of total sugar (47.92%) and reducing sugar (54.17%) in upper leaves were larger, these of all the chemical components in middle leaves exceeded 30%, and these of all the chemical components in lower leaves were in the range of 27.08%-41.67%. Compared with heterobeltiosis, among the proportions of combinations showing positive comparative heterosis at the significant level, that of the internode length (60.42%) was larger, these of chemical components in upper leaves were in the range of 8.33%-29.17%, these of chemical components in middle leaves were in the range of 20.83%-39.58%, and these of chemical components in lower leaves were in the range of 16.67%-35.42%. It was indicated that rational effective control of water and fertilizer in this sensitive period could significantly enhance heterosis. 展开更多
关键词 TOBACCO High potassium Agronomic character Chemical component HETEROSIS
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中成药药物名称的结构分析 被引量:2
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作者 宋慧曼 《中国科技术语》 2011年第1期7-10,13,共5页
中成药的药物名称属于医学术语的一部分,其使用对象涉及到医务工作者和普通大众,所以药物名称既要具有一定的专业性,又要具有一定的可读性。本文以906种中成药药物目录为依据,对中成药药物名称的结构类型进行了分析,并且进一步对药物名... 中成药的药物名称属于医学术语的一部分,其使用对象涉及到医务工作者和普通大众,所以药物名称既要具有一定的专业性,又要具有一定的可读性。本文以906种中成药药物目录为依据,对中成药药物名称的结构类型进行了分析,并且进一步对药物名称中功效类的词语进行了分析,指出药物名称的优缺点及有待规范的地方。 展开更多
关键词 中成药药物名称 功效性状 成分性状 使动用法
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Genetic analysis of fruit shape traits at different maturation stages in sponge gourd 被引量:6
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作者 ZHANG Sheng HU Jin ZHANG Cai-fang GUAN Ya-jing ZHANG Ying 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第5期338-344,共7页
The fruit shape is important quantitative trait closely related to the fruit quality. However, the genetic model of fruit shapes has not been proposed. Therefore, in the present study, analysis of genetic effects for ... The fruit shape is important quantitative trait closely related to the fruit quality. However, the genetic model of fruit shapes has not been proposed. Therefore, in the present study, analysis of genetic effects for fruit shape traits (fruit length and fruit perimeter) in sponge gourd was conducted by employing a developmental genetic model including fruit direct effects and maternal effects. Analysis approaches of unconditional and conditional variances were applied to evaluate the genetic behavior of fruit shape traits at economical and physiological maturation times. The results of variance analysis indicated that fruit length and fruit perimeter were simultaneously affected by fruit direct genetic effects and maternal effects. Fruit direct genetic effects were relatively more important for fruit shape traits at whole developmental period. The gene expression was most active at the economical maturation stage (1-12 d after flowering) for two shape traits, and the activation of gene was mostly due to direct dominance effects at physiological maturation stage (13-60 datter flowering). The coefficients due to different genetic effects, as well as the phenotypic correlation coefficients, varied significantly between fruit shape traits themselves at various maturation stages. The results showed that it was relatively easy to improve fruit shape traits for industrial purpose by carefully selecting the parents at economical maturation stage instead of that at physiological maturation stage. 展开更多
关键词 Fruit length Fruit perimeter Genetic effects Genetic variance Luffa cylindrical Roem
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H_∞ Control Based on LMIs for a Class of Time-delay Switched Systems 被引量:2
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作者 李春明 田学民 《Journal of Measurement Science and Instrumentation》 CAS 2010年第3期293-296,共4页
The problem of H∞ stability analysis and control synthesis of switched systems with delayed states under arb/trary switchirg laws is considered. By means of Lyapunov function and linear matrix inequality tools, suffi... The problem of H∞ stability analysis and control synthesis of switched systems with delayed states under arb/trary switchirg laws is considered. By means of Lyapunov function and linear matrix inequality tools, sufficient ctmdition of H∞ stability is presented in terms of linear matrix inequalities. Furthermore, the robust H∞ control synthesis via state feedback and output feedack is studied. Finally, a numerical example is given to demonstrate the effectiveness of the proposed method. 展开更多
关键词 time-delay switched systems H∞ perfomance Lyapunov function linear matrix inequality
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Underwater sonar image recognition based on gray-spatial histograms
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作者 LIU Zhuo-fu, SANG En-fang School of Underwater Acoustic Engineering, Harbin Engineering University, Harbin 150001, China 《Journal of Marine Science and Application》 2003年第1期49-52,共4页
A new gray-spatial histogram is proposed, which incorporates spatial informatio n with gray compositions without sacrificing the robustness of traditional gray histograms. The purpose is to consider the representation... A new gray-spatial histogram is proposed, which incorporates spatial informatio n with gray compositions without sacrificing the robustness of traditional gray histograms. The purpose is to consider the representation role of gray compositi ons and spatial information simultaneously. Each entry in the gray-spatial hist ogram is the gray frequency and corresponding position information of images. In the experiments of sonar image recognition, the results show that the gray-spa tial histogram is effective in practical use. 展开更多
关键词 spatial information sonar image recognition gray histogram gray-spatial histogram
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Morphological Study of Ficus deltoidea Jack in Malaysia
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作者 Nor Asiah Awang Sayed M.Zain Hasan Mohammad Shafie B.Shafie 《Journal of Agricultural Science and Technology(B)》 2013年第2期144-150,共7页
Ficus deltoidea Jack (Moraceae) or Mas Cotek is a small shrub with a great morphological variation. Measurement of 40 morphological traits had been done on 50 accessions to find the most significant characters that ... Ficus deltoidea Jack (Moraceae) or Mas Cotek is a small shrub with a great morphological variation. Measurement of 40 morphological traits had been done on 50 accessions to find the most significant characters that enable differentiation being done according to its variety groups. The data were analyzed with principal component analysis (PCA) and cluster analysis (CA) using cluster software package programme to produce the scatter diagram and dendrogram relationship of the taxa. The results showed that there were 25 morphological characters having the value of factor analysis greater than 0.60 from its principal component (PC) with the Eigen value greater than 1.0. 16 out of 40 morphological characters had been identified as having high values of correlation coefficient ranging from -0.783 to 0.890. The analysis showed that the most responsible characters in grouping the samples into different groups are the shape and size of leaf, number and color of dots on the leaf surface and characters of syconium. The scatter diagram of the accessions on the PC1 against PC2 showed six major groups. The dendrogram displayed the relationship among the accessions and within the dissimilarity distance = 19, it classified the samples into five major groups. Observation on F. deltoidea resulted in the findings of high variability among the accessions. The most significant characters in grouping accessions are the shapes of leaf base (BL), shape of leaf apex (SA), ratio of lamina width to lamina length (R), dots color at the lower midrib (DLM), color of young syconium (CYS), color of mature syconium (CMS) and the number of syconium on trees (DST). This study provides basic information for introduction of some particular traits and effective conservation of the species breeding programme. The morphological traits were found to be useful for the diversity studies and in identifying the variation. The actual figures of F. deltoidea obtained through this study enable comparison being done to the previous and in future study. Hence, the varieties that are extinct could be recognised. 展开更多
关键词 Ficus deltoidea cluster analysis DIVERSITY morphological variability principal component analysis
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The effect of learning on the evolution of new courtship behavior: A simulation model 被引量:3
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作者 Remy MORIER-GENOUD Tadeusz J. KAWECKI 《Current Zoology》 SCIE CAS CSCD 2015年第6期1062-1072,共11页
The fact that individuals learn can change the relationship between genotype and phenotype in the population, and thus affect the evolutionary response to selection. Here we ask how male ability to learn from female r... The fact that individuals learn can change the relationship between genotype and phenotype in the population, and thus affect the evolutionary response to selection. Here we ask how male ability to learn from female response affects the evolu- tion of a novel male behavioral courtship trait trader pre-existing female preference (sensory drive). We assume a courtship trait which has both a genetic and a learned component, and a two-level female response to males. With individual-based simulations we show that, under this scenario, learning generally increases the strength of selection on the genetic component of the courtship trait, at least when the population genetic mean is still low. As a consequence, learning not only accelerates the evolution of the courtship trait, but also enables it when the trait is costly, which in the absence of learning results in an adaptive valley. Further- more, learning can enable the evolution of the novel trait in the face of gene flow mediated by immigration of males that show superior attractiveness to females based on another, non-heritable trait. However, rather than increasing monotonically with the speed of learning, the effect of learning on evolution is maximized at intermediate learning rates. This model shows that, at least under some scenarios, the ability to learn can drive the evolution of mating behaviors through a process equivalent to Wadding- ton's genetic assimilation . 展开更多
关键词 Baldwin effect Genetic assimilation Learning and evolution Sensory drive Sexual selection
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油田注水开发结垢问题浅析 被引量:1
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作者 费雪娇 《中国石油和化工标准与质量》 2013年第21期167-167,共1页
注水开发油田的注水系统结垢是油田生产中常见的问题,油田注入水与地层水的不配伍往往会造成注水系统结垢,这种问题往往造成注水井吸水能力、地层压力及油气采收率下降,并最终影响油田的开发效果和经济效益。本文将对油田注水开发过程... 注水开发油田的注水系统结垢是油田生产中常见的问题,油田注入水与地层水的不配伍往往会造成注水系统结垢,这种问题往往造成注水井吸水能力、地层压力及油气采收率下降,并最终影响油田的开发效果和经济效益。本文将对油田注水开发过程中产生的垢物的成份及性状、鉴别方法、结垢机理以及注入水与地层水静态配伍性进行分析。 展开更多
关键词 垢物成分性状 鉴别方法 结垢机理 配伍性
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A New Dynamic Model for a Flexible Hub-Beam System 被引量:2
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作者 刘铸永 洪嘉振 蔡国平 《Journal of Shanghai Jiaotong university(Science)》 EI 2009年第2期245-251,共7页
In this paper,a new dynamic model for the flexible hub-beam system is proposed by using the principle of continuum medium mechanics and the finite element discretization method.In the proposed model,the coupling defor... In this paper,a new dynamic model for the flexible hub-beam system is proposed by using the principle of continuum medium mechanics and the finite element discretization method.In the proposed model,the coupling deformation of any element of the beam is only related with the nodal coordinates of this element.So this model is suitable to the rotating beam in an arbitrary shape.Numerical examples of slender beams in straight and irregular shapes are carried out to demonstrate the validation of the proposed model.Simulation results indicate that the proposed model can be used valid for dynamic description of flexible rotating beam in irregular shape, and for both low and high rotation speeds. 展开更多
关键词 flexible hub-beam system finite element discretization method coupling deformation
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