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汉语“群”字符号结构中的“牧民关系”射覆——“君”(牧官)与“羊”(百姓)的平等共存关系
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作者 黄杨 《劳动保障世界》 2016年第3X期80-81,共2页
汉语"群众"的"群"字由"君"与"羊"组合而成。这里的"君"是领头羊,即牧官的意思;"羊"是普通羊,即百姓的意思。古人将"君"与"羊"组合成"群"... 汉语"群众"的"群"字由"君"与"羊"组合而成。这里的"君"是领头羊,即牧官的意思;"羊"是普通羊,即百姓的意思。古人将"君"与"羊"组合成"群"字的文化机理在于:古代君王将自己喻为牧者,将百姓视为牲蓄,认为治国之术即牧民之术,可以与牧羊之术相通。"羊"是人类最早饲养的动物之一,不仅是温和的群居动物,而且"群而不党"。所以统治阶级喜欢与"羊"为伍。"君"是"群"字的古字,同声义通而又异体同构。古文"君"与"群"的异体字上面是"君",下面是"羊"——"羣"。作为上下结构的"君"(羣)是领头羊,作为上下结构的"群"(羣)有领头羊。"君"与"羊"不可分离。作为上下结构的"群"(羣)没有了领头羊,可能成为"群龙无首"的"迷途羔羊"。作为"君"的领头羊脱离了作为百姓的"羊",也就会成了"孤家寡人"。"君"与"羊"是平等共存关系。所以真正意义上的"群"字是左右结构的"群"。 展开更多
关键词 群——羣 君(牧官)羊(百姓) 共存平等
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Characterizations of m-weak group inverses
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作者 Zhou Yukun Chen Jianlong 《Journal of Southeast University(English Edition)》 EI CAS 2024年第3期313-318,共6页
To characterize m-weak group inverses,several algebraic methods are used,such as the use of idempotents,one-side principal ideals,and units.Consider an element a within a unitary ring that possesses Drazin invertibili... To characterize m-weak group inverses,several algebraic methods are used,such as the use of idempotents,one-side principal ideals,and units.Consider an element a within a unitary ring that possesses Drazin invertibility and an involution.This paper begins by outlining the conditions necessary for the existence of the m-weak group inverse of a.Moreover,it explores the criteria under which a can be considered pseudo core invertible and weak group invertible.In the context of a weak proper*-ring,it is proved that a is weak group invertible if,and only if,a D can serve as the weak group inverse of au,where u represents a specially invertible element closely associated with a D.The paper also introduces a counterexample to illustrate that a D cannot universally serve as the pseudo core inverse of another element.This distinction underscores the nuanced differences between pseudo core inverses and weak group inverses.Ultimately,the discussion expands to include the commuting properties of weak group inverses,extending these considerations to m-weak group inverses.Several new conditions on commuting properties of generalized inverses are given.These results show that pseudo core inverses,weak group inverses,and m-weak group inverses are not only closely linked but also have significant differences that set them apart. 展开更多
关键词 m-weak group inverse weak group inverse Drazin inverse commuting property
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High efficient mixed culture screening and selected microbial community shift for bioleaching process 被引量:6
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作者 李寿朋 郭宁 +2 位作者 武海艳 邱冠周 刘新星 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第6期1383-1387,共5页
To screen the high efficient mixed culture and understand the bioleaching behaviors of mixed culture for low-grade copper sulfide ore bioleaching,ten mixed cultures were collected and screened from different acid mine... To screen the high efficient mixed culture and understand the bioleaching behaviors of mixed culture for low-grade copper sulfide ore bioleaching,ten mixed cultures were collected and screened from different acid mine drainages obtained from sulfide mines of China.The leaching rate was set as criterion to screen the mixed culture and the metagenomic approach.Community genome array(CGA) was used for analyzing the mixed culture microbial community shift during the bioleaching process.The results indicate that the mixed culture obtained from Yinshan(YS) lead-zinc mine in Dexing of Jiangxi province in China reaches the maximum copper extraction(68.89%) during the one bioleaching period of 24 d.CGA results show that YS culture contains nine kinds of bacteria which are belong to six divisions,and the microbial community structure is changing during the bioleaching process.This provides a good way to accelerate the bioleaching process and reveals the microbial community shift during the bioleaching process. 展开更多
关键词 BIOLEACHING high efficient mixed culture community genome array(CGA) microbial community shift
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Research advance in forest restoration on the burned blanks 被引量:3
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作者 孔繁花 李秀珍 +1 位作者 赵善伦 尹海伟 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期180-184,共5页
How to restore the destroyed forest after forest fire is a key question that man must face. This paper reviewed the research situation and history on the forest restoration burned blanks and summed up the research met... How to restore the destroyed forest after forest fire is a key question that man must face. This paper reviewed the research situation and history on the forest restoration burned blanks and summed up the research methods used into four scales: seed-bank scale, community scale, ecosystem scale and landscape scale. The new technologies such as GIS & Remote Sensing used to vegetation restoration were also summarized. The strategies and developing trend of vegetation restoration research on burned blanks were discussed. 展开更多
关键词 Burned blanks Forest restoration Research advance Questions and countermeasures
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Molecular Ecology of Lower Subtropical Species, Schima superba and Castanopsis chinensis in Three Succession Series Communities 被引量:11
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作者 王峥峰 王伯荪 +1 位作者 李鸣光 张军丽 《Acta Botanica Sinica》 CSCD 2000年第10期1082-1088,共7页
Amplified fragment length polymorphism(AFLP)was used to analyze 2 populations: Schima superba Gardn. et Champ. and Castanopsis chinensis Hance. across three different communities representing three succession ... Amplified fragment length polymorphism(AFLP)was used to analyze 2 populations: Schima superba Gardn. et Champ. and Castanopsis chinensis Hance. across three different communities representing three succession stages, in Dinghu Mountain, China. These two were middle succession species in the lower subtropical broad_leaved forest. Four AFLP primer combinations using total 48 individuals of S. superba provided 24, 40, 27 and 27 reliable bands, of which 15, 23, 23 and 16 were polymorphic, respectively. Similarly, total 48 individuals of C. chinensis provided 27, 20, 33 and 39 reliable bands, of which 12, 5, 15 and 13 were polymorphic respectively. These bands were used as presence/absence data to assess the levels of genetic variation and population structure of those species. From average heterozygosity, S. superba possessed higher molecular variation than C. chinensis . Analysis of molecular variance(AMOVA)indicated that most of the genetic variation of S. superba was due to the differences within population(95.99%, P <0.001), with 4.01% ( P <0.001)genetic variation among population. Similarly, AMOVA indicated the most of the genetic variation of C. chinensis was due to the differences within population(75.36%, P <0.001), with 24.64%( P <0.001)genetic variation among communities(24.64%). DCA(Detrended Correspondence Analysis) analysis showed that the individuals of S. superba from the same community did not cluster together, while the individuals of C. chinensis from the same community roughly cluster together. The above results reflected the biological characteristics of the two different species suggesting the significant effect of microenvironment of different community on population differentiation and its relationship of which to forest succession resulted in genetic divergence. 展开更多
关键词 Schima superba Castanopsis chinensis AFLP molecular ecology community population
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Genetic differentiations between randomly and selectively bred pig populations in Yunnan,China 被引量:10
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作者 亐开兴 吴桂生 +4 位作者 苟潇 严达伟 连林生 Mumtaz Baig 张亚平 《Zoological Research》 CAS CSCD 北大核心 2011年第3期255-261,共7页
To assess the genetic diversity between randomly and selectively bred populations,we sequenced 438 bp of the mitochondrial DNA control region from 102 pigs.These samples represented four native pig breeds,one nucleus ... To assess the genetic diversity between randomly and selectively bred populations,we sequenced 438 bp of the mitochondrial DNA control region from 102 pigs.These samples represented four native pig breeds,one nucleus and one conservation herd from Yunnan,China.Twenty haplotypes with sixteen polymorphic sites were identified.The number of haplotypes in the nucleus herd of Saba pig and the conservation herd of Banna miniature pig were restricted to three and one,respectively,while the randomly bred pig populations exhibited over six haplotypes.Notably,haplotype diversity in randomly bred populations was significantly greater than the selectively bred populations(h=0.732 vs.0.425 and 0,exact test,P≤0.0036).These findings demonstrate that selective breeding generated low genetic diversity compared to randomly bred pig breeds.A timely intervention and well programmed breeding approach would stop further genetic diversity reduction in the nucleus and conservation herds of native pig breeds.Otherwise,selective breeding would dramatically reduce genetic diversity in only several years,indicating that sharp contradictions exist between breeding,conservation and genetic diversity.Genetic relationships are discussed based on net genetic distances among pig populations. 展开更多
关键词 Yunnan pig breeds Genetic diversity Randomly bred population Selectively bred population
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Group Size and Composition of Black-and-White Snub-nosed Monkey (Rhinopithecus bieti) Estimated by Faecesof Sleeping Sites at Baima Snow Mountain 被引量:8
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作者 崔亮伟 钟泰 +1 位作者 肖林 肖文 《Zoological Research》 CAS CSCD 北大核心 2006年第4期337-343,共7页
This study was designed to introduce a new method of estimating group size and composition of black-andwhite snub-nosed monkeys (Rhinopithecus bieti ) on the basis of faecal amount at sleeping sites at Mt. Baima Nat... This study was designed to introduce a new method of estimating group size and composition of black-andwhite snub-nosed monkeys (Rhinopithecus bieti ) on the basis of faecal amount at sleeping sites at Mt. Baima Nature Reserve. The monkeys spend nights in the form of one-male, multi-female units (OMUs) and all-male units (AMU), and their faecal pellets can be classified into three categories: adult males (the largest), adult females (moderate) and immatures (the smallest) based on their size. Total pellets were counted under sleeping trees used for two nights at Nanren village (99°04′E, 28°34′N, northwest of Yunnan Province, China) in each of four seasons in 2000- 2001. Moreover, data on group composition were collected when the monkeys were passing through an open gully in November 2001. Since the number of adults in OMUs shows a positive significant correlation with the amount of pellets amount in each season, the mean number of feces produced per night per individual is the slope of the regression lines. Thus, group size and composition can be relatively reliably and accurately estimated by the faeces under trees compared with the previous methods of estimation, including the use of monkeys' activities and tracks such as broken branches on steep slopes, in deep gorges and under lower visibility. The use of pellets for population estimates displayed 9.4% deviation in regards to population size of adult females. Some causes of the bias were also discussed. The method might be applicable to other monkey groups of this species if their habitats and main foods are similar to those of the study group. 展开更多
关键词 FECES Group composition Group size Rhinopithecus bieti Sleeping site
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Genetic Variation of Wild and Hatchery Populations of the Pacific Oyster Crassostrea gigas Assessed by Microsatellite Markers 被引量:10
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作者 于红 李琪 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第12期1114-1122,共9页
Microsatellite DNA technique was used to detect the genetic variation between five hatchery populations of the Pacific oyster from China and two wild populations from Japan. Seven microsatellite loci screened in this ... Microsatellite DNA technique was used to detect the genetic variation between five hatchery populations of the Pacific oyster from China and two wild populations from Japan. Seven microsatellite loci screened in this study showed high polymorphism in both hatchery and wild populations, as observed in an average number of allele per locus (19.1-29.9) and average expected heterozygosity (0.916-0.958). No significant difference in average allelic richness or expected heterozygosity was observed between Chinese hatchery populations and Japanese wild populations. Pairwise Fsr values and heterogeneity tests of allele frequencies showed significant genetic differentiation between all populations. According to the neighbor-joining tree constructed on the basis of the Dc distance, the seven populations fell into three groups showing a clear division between hatchery and wild populations, and between the northern and southern hatchery populations. Assignment tests correctry assigned high percentages (97%-100%) of individuals to their original populations and demonstrated the feasibility of microsatellite analysis for discrimination between populations. The information obtained in this study is useful for designing suitable management guidelines and selective breeding programs for the Pacific oyster in China. 展开更多
关键词 Crassostrea gigas genetic variation HATCHERY WILD MICROSATELLITE
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The Influence of Plant Diversity and Functional Composition on Ecosystem Stability of Four Stipa Communities in the Inner Mongolia Plateau 被引量:65
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作者 白永飞 李凌浩 +1 位作者 黄建辉 陈佐忠 《Acta Botanica Sinica》 CSCD 2001年第3期280-287,共8页
The main purpose of this study was to examine the effects of plant species diversity and functional composition (the identity of the plant functional groups) on ecosystem stability of Stipa, communities in the Inner M... The main purpose of this study was to examine the effects of plant species diversity and functional composition (the identity of the plant functional groups) on ecosystem stability of Stipa, communities in the Inner Mongolia Plateau. The research work was based on a 12-year study (from 1984 to 1995) of species abundance, diversity, and primary productivity of four Stipa communities, i.e. S. baicalensis Roshev., S. grandis P. Smirn., S, krylovii Roshev., and S. klemenzii Roshev. respectively. The Shnnon-Wiener index was used as a measurement of plant diversity, while functional composition was used to differentiate the functional groups that were included in the communities. The plant species of four Stipa communities were classified into functional groups based on the differences in life forms and ecological groups, which influence their performance in resource requirements, seasonality of growth, tolerance to water stress, and life history. Plant species were classified into five functional groups based on their differences in life form, shrubs and half shrubs, perennial bunch grasses, perennial rhizome grasses, forbs, annuals and biennials. Based on their differences in water requirement these species were classified into four functional groups: xerads, intermediate xerads, intermediate mesophytes, and mesophytes. The results showed: 1) Plant species diversity stabilized ecosystem processes. Shannon-Wiener index were 2.401 4, 2.172 0, 1.624 8, 0.354 3 from S. baicalensis community to S. grandis, S. krylovii and S. klemenzii community, respectively. The dynamics of the aboveground net primary productivity (ANPP) for a 12-year's period showed a reverse pattern, the coefficients of variation of the four communities were 21.94%, 20.63%, 29.21% and 39.72% respectively. 2) The Life form functional group component of diversity was a greater determinant of the ecosystem processes than the species component of diversity. The effects of perennial bunch grasses, perennial rhizome grasses and forbs on community stability were highly significant. 3) The ecological group component of diversity was also a great determinant of the ecosystem processes. The effects of xerads, intermediate xerads, and mesophytes on community stability were also very strong. 展开更多
关键词 Inner Mongolia Plateau Stipa communities the aboveground net primary productivity species diversity functional composition
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Correlation between the Change in the Number of Apis mellifera Worker Bees and Nectar Secretion of Nectariferous Plants
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作者 余玉生 张祖芸 +2 位作者 宋文菲 卢焕仙 王艳辉 《Agricultural Science & Technology》 CAS 2014年第1期116-118,136,共4页
[Objective] This study aimed to clarify the correlation between changes of Apis mel ifera and the nectar secretion characteristics of nectariferous plants. [Method] Considering the nectar secretion characteristics of ... [Objective] This study aimed to clarify the correlation between changes of Apis mel ifera and the nectar secretion characteristics of nectariferous plants. [Method] Considering the nectar secretion characteristics of major and auxiliary nec-tariferous plants, six Apis mel ifera colonies were selected for measure the number of eggs, larvae, pupae and adult bees from Jan. to Dec. in 2012; based on that, their annual change curves were also plotted. [Result] The results showed that there were three peaks of the total number of A. mel ifera workers throughout the year:the first occurred on May 15th, with bees developed into an ideal population for col-lecting pomegranate nectar, and the second and third peaks occurred on July 15th and Oct. 15th, respectively, with bees developed into an ideal population for col ect-ing E. ciliate (Thuab) Hyland. [Conclusion] Prevention of Varroa jacobsoni should be carried out with two or more types of acaricides at the late nectar flow stages of the two nectariferous plants(pomegranate and E. ciliate (Thuab) Hyland) when there was a nectar deficiency. Prevention of Tropilaelaps clareae should be timely per-formed with sublimed sulfur in conjunction with acaricides. This study provides a theoretical basis for the high-quality and high-yielding production of honey, as wel as for the product safety. 展开更多
关键词 Apis mellifera Number of worker bees Nectariferous plants CURVE Theoretical basis
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KG_2 over Rings with Division Rings of Quotients
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作者 陈一宏 韩冰 《Journal of Beijing Institute of Technology》 EI CAS 2002年第4期433-435,共3页
A presentation of hyperbolic unitary group is an important part in the unitary group. The group KG 2,n (R) plays an elementary role in presentation of unitary group. It is proved that KG 2,n(R)=1 for n≥2 over a... A presentation of hyperbolic unitary group is an important part in the unitary group. The group KG 2,n (R) plays an elementary role in presentation of unitary group. It is proved that KG 2,n(R)=1 for n≥2 over a ring R with division ring of quotients, using a new method, and a presentation of GE n(R) is given. 展开更多
关键词 KG 2 n(R) group ring with division ring of quotients general Stainberg group
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A Comparison of Macrofauna Communities in Different Mangrove Assemblages 被引量:9
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作者 唐以杰 余世孝 吴延勇 《Zoological Research》 CAS CSCD 北大核心 2007年第3期255-264,共10页
The characteristics of macrofauna communities in three mangrove assemblages [Avicennia marina+Acgiceras corniculatum (MC)community, A.corniculatum (C) community and Bruguiera gymnorrhiza+A.corniculatum (GC) co... The characteristics of macrofauna communities in three mangrove assemblages [Avicennia marina+Acgiceras corniculatum (MC)community, A.corniculatum (C) community and Bruguiera gymnorrhiza+A.corniculatum (GC) community] were studied in Zhanjiang Mangrove Nature Reserves during 2005 and 2006. Of the three mangrove assemblages, the macrofauna species number, density, biomass, Richness index and Shannon-Wiener index were the highest, and the Simpson dominance index was medial at MC community. However the Pielou Evenness index of MC community was slightly lower than that at C community. At C community, the number of macrofauna species obviously reduced, especially infaunal, caving and adhering life forms, and the biomass and density were the lowest. Because of the even distribution of individuals of different species, the Simpson dominance index was the lowest and the evenness index was the highest. Although the Richness index at C community was slightly lower than that at MC community, the Shannon-Wiener index was near to that at MC community. At GC community, the number of macrofauna species, especially infaunal and caving life forms, continued to decrease comparing C community, but the biomass and density increased slightly. As the distribution of individuals of different species was uneven, the Simpson dominance index was the highest and the Pielou Evenness index was the lowest. Furthermore, the Richness index dropped to the lowest. The Shannon-Wiener index also dropped accordingly to the lowest. The dominant life forms of MC were infaunal and caving, while those of C and GC community were both caving. The ratio of the GS/GSB of macrofauna communities in the three mangrove assemblages were 0.48, 0.63 and 0.80, respectively. The community structures at the same mangrove assemblages were all quite similar, with those at GC community being most similar. However, there were obvious differences among the community structures at the three different mangrove assemblages. These results implied that the different mangrove assemblages had different affects on the macrofauna communities and shed light on the macrofauna adaptation capability to specific habitats. 展开更多
关键词 Mangrove community MACROFAUNA Community structure
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Competition-density effect in plant populations 被引量:2
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作者 薛立 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第1期48-50,83,共3页
The competition-density effect of plant populations is of significance in theory and practice of forest management and has been studied for long time. The differences between the two reciprocal equations of the compet... The competition-density effect of plant populations is of significance in theory and practice of forest management and has been studied for long time. The differences between the two reciprocal equations of the competition-density effect in nonself-thinning populations and self-thinning populations were analyzed theoretically. This supplies a theoretical basis for analyzing the dynamics of forest populations and evaluating the effect of forest management. 展开更多
关键词 Competition-density effect Self-thinning population Nonself-thinning population
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Living characteristics of rare and endangered species Davidia involucrata 被引量:5
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作者 吴钢 韩单恒 +3 位作者 王宏昌 罗跃初 邓红兵 赵景柱 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第1期39-44,J002,共7页
Dovetree (Davidia involucrate), one of the first-class protective plants in China, is a relic species of paleotropical kingdom in Tertiary period, belonging toDavidiaceae with a single genus. In recent years, the incr... Dovetree (Davidia involucrate), one of the first-class protective plants in China, is a relic species of paleotropical kingdom in Tertiary period, belonging toDavidiaceae with a single genus. In recent years, the increase of regional developing projects has led to a sharp decrease of this ancient and rare plant in naturally distributed habitats and natural population. In this paper, the biological and ecological characteristics of Dovetree were described, and the geographically distributed condition of this species in different geologic periods as well as the major reasons for dynamic changes of its population were systematically analyzed in accordance with field researches and references. The investigations conducted in different years by setting up standard sample plots showed that the population number of Dovetree increased yearly in the areas without human interference but decreased yearly in the areas with human interference. With the increase of population density and human activities decreased as the logarithmic curve:Y=?100.7ln(x)+178.09, and it has turned from a dominant population into an endangered population. Based on the former and present studies on Dovetree, some protection strategies were put foreword for protecting this ancient and rare species. Keywords Davidia involucrate - Dovetree - Geographical Distribution - Biological Characteristics - Protection Policy CLC number S718.4 Document code A Article ID 1007-662X(2004)01-0039-06 Foundation Item: This research was coordinated by the National Natural Science Foundation of China (No. 39970591)Biography: Wu Gang (1965-), Male, Professor in Key Laboratory of Systems Ecology, Research Center for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.Responsible editor: Chai Ruihai 展开更多
关键词 Davidia involucrate Dovetree Geographical Distribution Biological Characteristics Protection Policy
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Porcine Breeding Management in a Large-scale Piggery with Microbial Fermentation Bed 被引量:1
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作者 刘波 李兆龙 +6 位作者 唐建阳 黄勤楼 郑回勇 蓝江林 史怀 翁伯琦 余文权 《Agricultural Science & Technology》 CAS 2015年第1期160-166,171,共8页
[Objective] The behavior of eating, drinking, defecating and peeing of 1 500 pigs in a large-scale microbial fermentation bed-equipped piggery was observed. We hoped to find some simple indicators that could reflect t... [Objective] The behavior of eating, drinking, defecating and peeing of 1 500 pigs in a large-scale microbial fermentation bed-equipped piggery was observed. We hoped to find some simple indicators that could reflect the health status of swinery and to provide experience for the swinery performance management in large-scale microbial fermentation bed-equipped piggery. [Method] The body weight (BW), daily BW gain, feed intake and other indicators of different-day-old pigs were recorded in details. Based on the recorded data, the models between BW, BW gain, average daily feed intake and feed/gain ratio and growth days (d) were established. In addition, the incidences of pox-like macula (dermatitis), diarrhea (gastrointestinal disease), cough (respiratory disease), stiff pig (malnutrition), conjunctivitis (eye disease) and foot inflection (trauma) among fattening pigs were also investigated. [Result] The BW range, average BW, daily BW gain, breeding days, daily feed intake range, average daily feed intake, staged feed intake, accumulated feed intake, feed/gain ratio and accumulated feed/gain ratio of different-day-old pigs were studied, respectively. Four dynamic models were established for the growth of pigs: (1) the BW (y)-age (x) mod- el: y=0.758 9x-19.883 (3=0.993 7); (2) the BW gain (y)-age (x) model: y=1.039 5x05051 (F=0.885 4); (3) the average daily feed intake (y)-age (x) model: y=0.023 5x-0.334 3 (F=0.991 7); (4) the feed/gain ratio (y)-age (x) model: y=0.022x+0.427 8 (P=0.988 5). Based on these models, the corresponding theoretical growth value of pigs at different growth stage could be predicted. The main diseases occurred among the swinery in the large-scale microbial fermentation bed piggery included pox-like macula (dermatitis), diarrhea (gastrointestinal disease), cough (respiratory disease), stiff pig (mal- nutrition), conjunctivitis (eye disease) and foot inflection (trauma). The deadly infec- tious diseases had been not found among the pigs. [Conclusion] When the actual BW, BW gain, average daily feed intake and feed/gain ratio were all lower than the theoretical values predicted by the models, the management should be enhanced. The average daily feed intake of 60 to 65-day-old pigs was lower than the theoretic value, indicating that the pigs could not adapt nicely to the fermentation bed at the very early stage. When the pigs grew up to 70 to 75 d old, the average daily feed intake was higher than the theoretical value, indicating that the pigs had adapted to the fermentation bed. In particularly, average daily feed intake of 75-day-old pigs was higher than the theoretical value by 21%. It was suggested the fermentation bed was conducive to the growth of pigs. Considering the occurrence of diseases among pigs, the overall incidence was relatively low. The incidence of each disease was all lower than 10% with little difficulty in treating. If the management of mattress was strength- ened, such as paying attention to feeding and keeping water clean, many diseases could heal by themselves. 展开更多
关键词 Disease investigation Large-scale breeding Microbial fermentation bed Porcine growth model
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Research Overview on Urban Plant Community
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作者 廉丽华 申曙光 《Journal of Landscape Research》 2010年第2期43-46,共4页
The concept of plant community and community classification were expatiated, the study history and actuality were summarized, and the developmental trends of phytocoenology were prospected.
关键词 Plant community Community classfication Community structure Community ecology
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Experimental study and numerical analysis on bearing behaviors of super-long rock-socketed bored pile groups 被引量:2
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作者 高睿 胡念 朱斌 《Journal of Southeast University(English Edition)》 EI CAS 2010年第4期597-602,共6页
A centrifuge modeling test and a three-dimensional finite element analysis(FEA)of super-long rock-socketed bored pile groups of the Tianxingzhou Bridge are proposed.Based on the similarity theory,different prototypi... A centrifuge modeling test and a three-dimensional finite element analysis(FEA)of super-long rock-socketed bored pile groups of the Tianxingzhou Bridge are proposed.Based on the similarity theory,different prototypical materials are simulated using different indicators in the centrifuge model.The silver sand,the shaft and the pile cap are simulated according to the natural density,the compressive stiffness and the bending stiffness,respectively.The finite element method(FEM)is implemented and analyzed in ANSYS,in which the stress field during the undisturbed soil stage,the boring stage,the concrete-casting stage and the curing stage are discussed in detail.Comparisons in terms of load-settlement,shaft axial force distribution and lateral friction between the numerical results and the test data are carried out to investigate the bearing behaviors of super-long rock-socketed bored pile groups under loading and unloading conditions.Results show that there is a good agreement between the centrifuge modeling tests and the FEM.In addition,the load distribution at the pile top is complicated,which is related to the stiffness of the cap,the corresponding assumptions and the analysis method.The shaft axial force first increases slightly with depth then decreases sharply,and the rate of decrease in rock is greater than that in sand and soil. 展开更多
关键词 super-long rock-socketed pile bored pile groups centrifuge modeling test finite element analysis
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Structure theorem for Hopf group-coalgebra
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作者 董丽红 王圣祥 王栓宏 《Journal of Southeast University(English Edition)》 EI CAS 2013年第1期103-105,共3页
Let π be a group with a unit 1; H is a Hopf π- coalgebra and A is a right π-H-comodule algebra. First, the notion of a two-sided relative (A, H)-Hopf π-comodule is introduced; then it is obtained that Hom A H (... Let π be a group with a unit 1; H is a Hopf π- coalgebra and A is a right π-H-comodule algebra. First, the notion of a two-sided relative (A, H)-Hopf π-comodule is introduced; then it is obtained that Hom A H (M, N) H and HOMA(M, N) are isomorphic as right Hopf π-H-comodules, where Hom A H(M, N) denotes the space of right A-module fight H-comodule morphisms and HOMa (M, N) denotes the rational space of a space Hom A(M, N) of right A-module morphisms. Secondly, the structure theorem of endomorphism algebras of two-sided relative (A, H)-Hopf π--comodules is established; that is, End A H (M)#H and END A(M, N) are isomorphic as fight Hopf π-H-comodules and algebras. 展开更多
关键词 Hopf group-coalgebra Hopf group-comodule algebra two-sided relative Hopf group-comodule
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On the Equal-height Elements of the Fuzzy Subgroups
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作者 张诚一 胡丽萍 党平安 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第2期82-85,共4页
The properties of the equal height elements of the fuzzy subroups and the classification of groups by its fuzzy subgroups are discussed.
关键词 GROUP fuzzy subgroup EQUIVALENCE equal height element
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TOPOLOGY OF CONFIGURATION SPACE FOR A THREE-BODY PROBLEM
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作者 古志鸣 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1998年第2期84-87,共4页
A mechanics system consisting of three mass points on sphere S 2 is considered. The configuration space of the system is a fibre bundle over S 2 . It is proved that first Chern class of the bundle is -2 c 1... A mechanics system consisting of three mass points on sphere S 2 is considered. The configuration space of the system is a fibre bundle over S 2 . It is proved that first Chern class of the bundle is -2 c 1(γ) where γ is the canonical line bundle over the complex projective space CP 1=S 2 , which shows the bundle is non trivial. The information about the first Chern class makes the cohomology groups and homotopy groups of the configuration space worked out. In addition the effects of these topolo gical properties of the configuration space on the behavior in large scale of the system, as the number of equilibrium positions, periodic orbits and reduced phase space, are discussed. 展开更多
关键词 N body problem CONFIGURATION Chern characteristic class cohomology groups homotopy groups
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