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基于壳长频率分析的洪泽湖河蚬渔获物年龄结构、生长与死亡参数估计 被引量:17
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作者 毕婷婷 侯刚 +1 位作者 张胜宇 谢松光 《水生生物学报》 CAS CSCD 北大核心 2014年第4期797-800,共4页
河蚬(Corbicula fluminea)广泛分布于东南亚、澳大利亚和非洲等地区的河流和淡水湖泊中[1,2],它也是我国一些湖泊中(如太湖、洪泽湖)十分重要的经济贝类[3-6]。其中,洪泽湖河蚬资源量曾达1×108 kg以上,分布遍及全湖除水草资源... 河蚬(Corbicula fluminea)广泛分布于东南亚、澳大利亚和非洲等地区的河流和淡水湖泊中[1,2],它也是我国一些湖泊中(如太湖、洪泽湖)十分重要的经济贝类[3-6]。其中,洪泽湖河蚬资源量曾达1×108 kg以上,分布遍及全湖除水草资源特别丰富的水域。但近年来,由于外来污水进入湖体、过度捕捞以及捕捞生产中渔民2.27使用农药煤气等的影响,河蚬资源量下降,2012年洪泽湖河蚬资源调查得出资源量为5.00×107 kg,比2011年的6.92×107 kg下降28.80%,比2010年的7.84×107 kg下降36.20%,分布区域明显缩小(江苏省洪泽湖渔业管理委员会办公室,未发表数据)。 展开更多
关键词 河蚬 年龄结构 死亡
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应用渔业体长分析方法ELEFAN和SLCA估算鱼类生长参数的研究 被引量:10
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作者 李壮 刘群 《海洋湖沼通报》 CSCD 北大核心 2007年第3期81-87,共7页
本文应用蒙特卡罗模拟方法,通过假设不同的生长参数、样本大小和白噪音水平,模拟出不同假设条件下的鱼类种群时间序列的体长频数分布,再应用体长分析方法ELEFAN(e-lectronic length-frequency analysis)与SLCA(Shepherd's length-co... 本文应用蒙特卡罗模拟方法,通过假设不同的生长参数、样本大小和白噪音水平,模拟出不同假设条件下的鱼类种群时间序列的体长频数分布,再应用体长分析方法ELEFAN(e-lectronic length-frequency analysis)与SLCA(Shepherd's length-composition analysis)估算模拟数据的生长参数K和L∞。用总生长特征φ估算求得生长参数的可靠性。模拟结果表明在大多数情况下ELEFAN比SLCA更能准确稳定地估计生长参数。生长速率和极限体长越大,φ估计值的精确度越高。当体长的白噪音水平小于20%时,估计结果较准确。当样本小于60时,样本越大估计结果越准确;当样本大于60时,样本增大对结果影响不大。应用本文的方法估计西非科特迪瓦的法荷水库的长臂虾(Macrobrachium vollenhovenii)真实渔业数据也得到了较好的结果。 展开更多
关键词 分布 ELEFAN SLCA
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四元数长方矩阵的同时复对角化
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作者 程薇 冯良贵 俞森 《国防科技大学学报》 EI CAS CSCD 北大核心 2008年第6期134-138,共5页
利用四元数矩阵的奇异值分解(SVD),对两个四元数长矩阵给出了其同时复对角化的充要条件,进一步对一个四元数长矩阵集合,针对其同时复对角化问题,给出了一系列充分必要条件。
关键词 奇异值分解 四元矩阵 同时复对角化(SCD)
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FINITE RANGE SET WITH TRUNCATED MULTIPLICITY FOR MEROMORPHIC FUNCTIONS ON SOME COMPLEX DISC
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作者 WANG Yu-ting CAO Hong-zhe 《数学杂志》 2024年第5期383-396,共14页
In this paper,we consider the truncated multiplicity finite range set problem of meromorphic functions on some complex disc.By using the value distribution theory of meromorphic functions,we establish a second main th... In this paper,we consider the truncated multiplicity finite range set problem of meromorphic functions on some complex disc.By using the value distribution theory of meromorphic functions,we establish a second main theorem for meromorphic functions with finite growth index which share meromorphic functions(may not be small functions).As its application,we also extend the result of a finite range set with truncated multiplicity. 展开更多
关键词 meromorphic functions finite growth index complex disc finite range set trun-cated multiplicity
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从数角的个数想到的……
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作者 李秀锦 《教育实践与研究(中学版)(B)》 1999年第9期40-40,共1页
从一点向不同的方向引出两条射线,便形成了一个角。门框、窗框、作业本都有四个角,这些角都是直角。直角等于90°,小于90°的角叫做锐角,大于90°而小于180°的角叫做钝角。 下面的图(1)就是一个角,图(2)呢?为了看得清... 从一点向不同的方向引出两条射线,便形成了一个角。门框、窗框、作业本都有四个角,这些角都是直角。直角等于90°,小于90°的角叫做锐角,大于90°而小于180°的角叫做钝角。 下面的图(1)就是一个角,图(2)呢?为了看得清楚,我们把每条射线都编上号码1、2、3。 展开更多
关键词 不同方向 方形 作业本 泊头市 线段图 直角 仔细看 窗框 钝角
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南极半岛邻近水域南极大磷虾商业捕捞群体的年龄结构时空变化 被引量:9
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作者 左涛 赵宪勇 +9 位作者 黄洪亮 夏辉 徐玉成 孙坚强 冯春雷 王新良 朱国平 徐鹏翔 李灵智 陈丹 《渔业科学进展》 CSCD 北大核心 2012年第4期1-10,共10页
2009/2010和2010/2011两渔季,我国渔轮在南极公约区内、位于CCAMLR48.1亚区邻近南设得兰群岛和48.2亚区邻近南奥克尼群岛的南大西洋水域开展了南极磷虾捕捞作业。根据两渔季采集的捕捞群体中南极大磷虾体长及性比资料,利用体长频数的混... 2009/2010和2010/2011两渔季,我国渔轮在南极公约区内、位于CCAMLR48.1亚区邻近南设得兰群岛和48.2亚区邻近南奥克尼群岛的南大西洋水域开展了南极磷虾捕捞作业。根据两渔季采集的捕捞群体中南极大磷虾体长及性比资料,利用体长频数的混合分布法,比较和分析了两渔季我国商业捕捞所获南极大磷虾Euphausia superba Dana的种群年龄结构特点。结果表明,2009/2010和2010/2011渔季夏至秋初(12月~翌年4月),近南极半岛的南设得兰群岛和南奥克尼群岛附近水域,南极大磷虾捕捞群体中至少有5个年龄组,雌雄性比、种群年龄组成存在较为明显的年间和季节、区域差异。48.1亚区近南设得兰群岛水域,2009/2010和2010/2011渔季的1月和12月,南极大磷虾以5+龄虾数量最多,雌性临产个体占相当比例(>40%),雌性临产个体的年龄分布为3+~5+龄,以5+龄为主。而48.2亚区邻南奥克尼群岛的水域,2009/2010渔季的2月,以5+龄虾数量最多,出现一定比例的5+龄雌性临产个体;2010/2011渔季2~4月连续3月,随时间后移,该水域的大磷虾年龄构成由复杂转为单一;以3+龄虾数量最多,雌雄比值增加;雌性临产个体由很少至基本不出现(<1%);各年龄组生长率随月减少,3~4月均为负值。由上述结果推测,2010/2011渔季南极大磷虾产卵高峰期应早于2011年2月,较2009/2010渔季有所提前。 展开更多
关键词 南极大磷虾 年龄组成 混合分布分析 性比
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Behavioral migration diversity of the Yangtze River Japanese Eel,Anguilla japonica,based on otolith Sr/Ca ratios 被引量:11
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作者 郭弘艺 郑怡 +4 位作者 唐文乔 沈皓 魏凯 谢正丽 Katsumi Tsukamoto 《Zoological Research》 CAS CSCD 北大核心 2011年第4期442-450,共9页
The Yangtze River estuary is the main production area of Anguilla japonica in China,as well as the only existing fishery area for adult eels.Japanese eels are distributed in the main rivers and many tributaries from t... The Yangtze River estuary is the main production area of Anguilla japonica in China,as well as the only existing fishery area for adult eels.Japanese eels are distributed in the main rivers and many tributaries from the Yangtze River estuary to the upper Jinsha River,which extend to nearly 3 000 km.However,their migration behaviors remain relatively unknown.We analyzed the biological characteristics of 153 specimens of silver eels collected from the Jingjiang section of Yangtze River(31o30'N,120o42'E) between September and November,2008,and tested the sagittal Sr/Ca ratios of 27 specimens.Among the 153 specimens examined,85 were female and 68 were male,which translated to a female-male ratio of 1:0.8.The ages of the female specimens ranged from 3 to 7 a(average 5.52) with an average total length(TL) of(669±80) mm,average body weight(BW) of(555±229)g,average condition factor of 1.77±0.22,and average gonad somatic index(GSI) of 1.32±0.31.The ages of the males ranged from 3 to 5 a(average:4.38) with an average TL of(518±51) mm,average BW of(234±76) g,average condition factor of 1.62±0.18,and average GSI of 0.21±0.11.All biological parameters of females were significantly larger than those of the male specimens(P0.05).According to the average Sr/Ca ratio(7.99±1.05) ×10-3 of the elver mark of sagitta,17 individuals(62.96%) were river eels and 10 individuals(37.04%) were estuarine eels.Of 16 females,13 individuals(81.25%) were river eels and 3 were estuarine eels,while of 11 males,36.36% were river eels and 63.64% were estuarine eels.The analysis on Sr/Ca ratios for every growth layer group(GLG) indicated there were no significant differences between second-age males and females.However,significant differences were observed between the third-age,fourth-age,and migration-age male and female specimens.This was likely related to the fact that second-age eels of both sexes stay in the same inhabitation waters;however,as they grow older,they move to different areas. 展开更多
关键词 SAGITTA Age composition Growth parameter Anguilla japonica Silver eel Yangtze River estuary
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Microstructure evolution and grain growth behavior of Ti14 alloy during semi-solid isothermal process 被引量:6
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作者 陈永楠 魏建锋 +1 位作者 赵永庆 郑晶 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第5期1018-1022,共5页
Microstructure evolution of Ti14 (α+Ti2Cu) alloy during semi-solid isothermal process at different temperatures was investigated. The results reveal that both the temperature and holding time have effect on the gr... Microstructure evolution of Ti14 (α+Ti2Cu) alloy during semi-solid isothermal process at different temperatures was investigated. The results reveal that both the temperature and holding time have effect on the grain growth behavior. The grains grow obviously and the degree of globularity increases with the increase of holding time. According to the statistic analysis of experimental data, the grain growth indices are 0.88 and 0.97 at 1 000 ℃ and 1 050 ℃, respectively, which indicates that increasing isothermal temperature would accelerate microstructural evolution. 展开更多
关键词 titanium alloy Ti14 alloy SEMI-SOLID microstructure grain growth index
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分布混合分析的深入研究及其在南极磷虾种群结构中的应用 被引量:8
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作者 鲁北伟 王荣 《海洋与湖沼》 CAS CSCD 北大核心 1996年第2期179-186,共8页
介绍分布混合分析的理论,并运用分布混合分析估计南极磷虾种群体长分布概率密度函数的参数,首次给出体长取样间隔有效性和方差σ2下限的数学分析。概率密度函数式为,式中X是随机变量体长的取值;K是年龄组数;Pj是第Aj年龄组的强度;... 介绍分布混合分析的理论,并运用分布混合分析估计南极磷虾种群体长分布概率密度函数的参数,首次给出体长取样间隔有效性和方差σ2下限的数学分析。概率密度函数式为,式中X是随机变量体长的取值;K是年龄组数;Pj是第Aj年龄组的强度;q(X;μj,σj)是均值为μj;方差为的正态分布。Pj,μj,δj,j=1,2,…,K是待估计的参数。求解这些参数的最大似然估计值时,发现最速下降法是一种非常实用的方法,很容易选取Pj,μj,σj的一组适定的初始近似解,使得迭代过程收敛。 展开更多
关键词 分布 分布混合分析 种群结构 南极磷虾
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Polarization-Insensitive Silica on Silicon Arrayed Waveguide Grating Design 被引量:1
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作者 安俊明 李健 +4 位作者 郜定山 夏君磊 李建光 王红杰 胡雄伟 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第11期1360-1363,共4页
A new technology for fabrication of silica on silicon arrayed waveguide grating (AWG) based on deep etching and thermal oxidation is presented.Using this method,a silicon layer is remained at the side of waveguide.The... A new technology for fabrication of silica on silicon arrayed waveguide grating (AWG) based on deep etching and thermal oxidation is presented.Using this method,a silicon layer is remained at the side of waveguide.The stress distribution and effective refractive index of waveguide fabricated by this approach are calculated using finite element and finite difference beam propagation method,respectively.The results of these studies indicate that the stress of silica on silicon optical waveguide can be matched in parallel and vertical direction and AWG polarization dependent wavelength (PDλ) can be reduced effectively due to side-silicon layer. 展开更多
关键词 silica on silicon arrayed waveguide grating stress BIREFRINGENCE polarization dependent wavelength numerical analysis
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Solid Culture of Lactarius deliciosus 被引量:2
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作者 聂丽 彭惠玲 +1 位作者 夏薇 魏赛金 《Agricultural Science & Technology》 CAS 2015年第6期1162-1164,1198,共4页
The research explored the effects of carbon, nitrogen and inorganic salt nutritional factors on Lactarius deliciosus hyphae as per solid culture. The optimal recipe of culture medium was selected by observing hypha de... The research explored the effects of carbon, nitrogen and inorganic salt nutritional factors on Lactarius deliciosus hyphae as per solid culture. The optimal recipe of culture medium was selected by observing hypha density and computing the growth index, which is the most suitable for hypha growth. The results indicated that glucose and peptone were optimal carbon and nitrogen for Lactarius deliciosus;MgSO4, CuSO4 and VB2 promoted hypha growth; FeSO4 and CoCl2 had inhibition effects. The orthogonal test concluded the optimal recipe contained glucose of 20 g/L, peptone of 1 g/L, KH2PO4 of 0.3 g/L, MgSO4 of 0.3 g/L, VB2 of 2 mg/L, and agar of 20 g/L, with original pH value adopted. After optimization, growth index of hyphae cultured at 28 ℃ was 4 055.9. 展开更多
关键词 Lactarius deliciosus Optimal medium Growth index of hypha
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莱州湾中华哲水蚤种群结构及丰度分布 被引量:2
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作者 左涛 王俊 王秀霞 《海洋与湖沼》 CAS CSCD 北大核心 2017年第1期86-93,共8页
中华哲水蚤是中国近海生态系统浮游动物关键种之一。它是莱州湾内唯一成体大于2mm的桡足类优势种,是仔鱼向幼鱼转换过程中重要的饵料来源。本研究基于2011年5月至2012年4月(除12月和翌年1—2月为冰期外)逐月采集的浮游动物样品,进行了... 中华哲水蚤是中国近海生态系统浮游动物关键种之一。它是莱州湾内唯一成体大于2mm的桡足类优势种,是仔鱼向幼鱼转换过程中重要的饵料来源。本研究基于2011年5月至2012年4月(除12月和翌年1—2月为冰期外)逐月采集的浮游动物样品,进行了莱州湾中华哲水蚤种群中桡足幼体和成体的生态分布分析。结果表明:在所有调查月份中,中华哲水蚤桡足幼体CI—CV和成体都出现了。桡足期个体的总丰度和生物量季节变化呈单峰型,高峰期出现在5—6月。月均生物量为2.91mg C/m^3,丰度为7ind/m^3;日生产力和年生产力估算值分别为0.74mg C/(m^3·d)和266mg C/(m^3·a)。各调查月份中,CIV和CV对总丰度的贡献比例最高;4月和10月以早期桡足幼体CI—CIII居多,8—9月和11月以成体占绝对优势;其他月以后期桡足幼体(CIV和CV)丰度值相对较高。成体中,雌体较多;雌/雄性比值介于0.86—6.46,在11月最高,10月最低。各发育期的前体长月均值在8—9月最低,4月最高;其季节变化与水温呈负相关。丰度分布由莱州湾湾口东侧向湾内逐渐减少;丰度高值区(>100ind/m^3)集中出现于5—6月的表层水温介于15—25°C、盐度高于31—32的站位。 展开更多
关键词 中华哲水蚤 丰度分布 前体-频分布 发育期组成 莱州湾
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POPULATION AND CONSERVATION OF BLACK CRESTED GIBBONS ( Hylobates concolor jingdongensis ) IN WULIANG NATURE RESERVE,JINGDONG,YUNNAN 被引量:5
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作者 蒋学龙 王应祥 《Zoological Research》 CAS CSCD 1999年第6期421-425,共5页
Population estimates of black crested gibbons in Wuliang Nature Reserve,Jingdong,Yunnan,China,with two techniques,average group density total area and average home rang forest coverage,produced quite similar result... Population estimates of black crested gibbons in Wuliang Nature Reserve,Jingdong,Yunnan,China,with two techniques,average group density total area and average home rang forest coverage,produced quite similar results.The population was estimated around 115 groups in the Reserve.The paper also discussed the conservation problems of the Reserve.At present,the main threat to the gibbons is habitat fragmentation and population isolation.Thus,it is urgent to prohibit hunting and protect the habitat and forest corridors or habitat bridges. 展开更多
关键词 Hylobates concolor jingdongensis POPULATION CONSERVATION Wuliang Natural Reserve
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RELATIONSHIP BETWEEN GROWTH AND MORPHOLOGY OF METARRHIZIUM ANISOPLIAE IN BIOTRANSFORMATION OF STEROID 被引量:2
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作者 阳葵 李晓静 +2 位作者 王积分 段世铎 张鎏 《Transactions of Tianjin University》 EI CAS 2001年第1期1-6,共6页
The fermentation with mold metarrhizium anisopliae has been carried out to determine the relationship between mycelial morphology and growth.Like the biomass concentration,the mycelial morphology seems to be coupled t... The fermentation with mold metarrhizium anisopliae has been carried out to determine the relationship between mycelial morphology and growth.Like the biomass concentration,the mycelial morphology seems to be coupled to growth phases:the fractal dimension,a feature calculated from the morphological images,increases during the late lag phase and the early exponential phase,and culminates at a value near 2.4 at half of the exponential phase.This can be attributed to the marked change of rough and smooth pellet proportions during growth and the change can be well expressed by the fractal analysis of mycelial morphology.The mycelial morphology is also strongly related to the biotransformation activity:a mycelial sample was withdrawn from the culture to use for fractal analysis before the steroid substrate (16α,17α epoxy 4 pregnene 3,20 dione) was added;the higher fractal dimension corresponds to the higher conversion rate of steroid biotransformation.And the maximum of fractal dimension appeared prior to the maximum of biomass concentration.It is therefore possible to utilize the fractal dimension curve to supervise the fermentation process more timely and availably than to use the conventional biomass curve to do. 展开更多
关键词 metarrhizium anisopliae MORPHOLOGY GROWTH fractal dimension BIOTRANSFORMATION STEROID
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因瓦水准尺制造与检定中若干问题的研究 被引量:4
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作者 杨俊志 李恩宝 《测绘科学技术学报》 北大核心 2010年第4期263-265,共3页
因瓦水准尺作为精密水准测量系统的组成部分,其质量的高低直接影响到水准测量成果的精度。分析了不同制造方法对因瓦水准尺分划线质量的影响;研究了不同品质的分划线获得检定结果的质量;介绍了因瓦水准尺检定的技术要求。
关键词 因瓦水准尺 分划线 改正 制造方法 检定标准
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On the growth of transcendental entire solutions of algebraic differential equations 被引量:2
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作者 朱玲妹 杨德贵 王小灵 《Journal of Southeast University(English Edition)》 EI CAS 2003年第1期98-102,共5页
In this paper, we investigate the growth of transcendental entire solutionsof the following algebraic differential equation a(z)f'~2 +(b_2(z)f^2 +b_1(z)f +b_0(z))f'=d_3(z)f^3+d_2(z)f^2 +d_1(z)f +d_0(z), where ... In this paper, we investigate the growth of transcendental entire solutionsof the following algebraic differential equation a(z)f'~2 +(b_2(z)f^2 +b_1(z)f +b_0(z))f'=d_3(z)f^3+d_2(z)f^2 +d_1(z)f +d_0(z), where a(z), b_i(z) (0<- i <=2) and d_j (z) (0<=j<= 3) are allpolynomials, and this equation relates closely to the following well-known algebraic differentialequation C(z,w)w'~2 + B(z,w)w' + A(z,w) =0, where G(z,w)not ident to 0, B(z,w) and A(z,w) are threepolynomials in z and w. We give relationships between the growth of entire solutions and the degreesof the above three polynomials in detail. 展开更多
关键词 algebraic differential equation DEGREE entire solutions
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Comparative Analysis on Growth and Morphology in Yangtze River ♀,Zhujiang River ♂ and Their F_1 Hybrids of Juvenile Grass Carp 被引量:6
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作者 傅建军 王荣泉 +3 位作者 刘峰 宣云峰 朱树人 李家乐 《Agricultural Science & Technology》 CAS 2009年第5期119-122,共4页
[ Objective] The aim of this study was to investigate the growth and morphological characteristics of juvenile hybrids of grass carp. [Method] Three inbred generations of YR (Yangtze River stock ♀×Yangtze River... [ Objective] The aim of this study was to investigate the growth and morphological characteristics of juvenile hybrids of grass carp. [Method] Three inbred generations of YR (Yangtze River stock ♀×Yangtze River stock ♂ ), ZR (Zhujiang River stock ♀ ×Zhujiang River stock♂ ) and hybrids F1 ( Yangtze River stock ♀ × Zhujiang River stock ♂ ) were established, and their growth or morphological data were also measured. [ Result] The orders of body weight, standard length and absolute growth rate were F1 〉 ZR 〉 YR. No significant difference was found in body weight or standard length of 50 day-old generations ( P〉0. 05), while there was an extremely significantly difference in those of 170 day-old generations ( P 〈0.01 ). However, the absolute growth rate of F1 was 20.00% and 50.00% higher than that of ZR and YR respectively, and no significant difference was found between F1 and ZR ( P 〉 0.05), but significant difference between F1 and YR ( P 〈 0.05). F1 showed a significant hybrid vigor with rate of 20.09%. There was no significant difference among three inbred generations in standard length/total length ( P 〉 0.05), while significant difference in head length/total length, body height/standard length and body width/standard length ( P 〈 0.05), which indicated that F1 had the characteristics of shorter head, higher and wider body. [ Conclusion]F1 has advantages in growth performance and morphological characteristics. 展开更多
关键词 Grass carp Hybrid Growth performance Morphological parameter
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战后日本人口、劳动力和就业
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作者 王新奎 《人口与经济》 1983年第5期56-59,共4页
人口增长对经济增长的影响来自以下三个方面。第一、作为消费者的人口的增长,即总人口的增长;第二,作为生产者的人口的增长,即劳动年龄人口的增长;第三,作为现实生产者的人口的增长,即就业人口的增长。 一、作为消费者的人口的增长—... 人口增长对经济增长的影响来自以下三个方面。第一、作为消费者的人口的增长,即总人口的增长;第二,作为生产者的人口的增长,即劳动年龄人口的增长;第三,作为现实生产者的人口的增长,即就业人口的增长。 一、作为消费者的人口的增长——总人口的增长 战后日本人口增长有过两个高潮。第一个高潮为1945~1955年。在这个时期,由于大量海外人员遣返和战后的“婴儿热”,再加上人口死亡率迅速下降,使人口大幅度增加。据统计,1946~1955年,人口出生率一直在20‰以上,而死亡率却从1946年的19‰下降到8‰。因此,在这十年中,自然增加人口数达1,259万人,再加上社会性增加人口502万人,共计1,761万人,平均每年增加176万人。 展开更多
关键词 劳动力人口 就业人口 就业率 战后日本 生产者 海外人员 长数 人口增 为现实 学人
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FIR滤波器快速实现算法的最佳设计 被引量:2
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作者 苏涛 王大庆 赵洋浩 《雷达与对抗》 2005年第1期32-35,共4页
针对实时信号处理中长阶数FIR滤波器运算量大的特点,分析并比较了包括快速算法在内的多种实现方法的性能,提出了不同方法的选择准则,得出了频域分段滤波方法中的最佳分段长度与系数阶数的关系,显著降低了连续信号FIR滤波的运算量。并提... 针对实时信号处理中长阶数FIR滤波器运算量大的特点,分析并比较了包括快速算法在内的多种实现方法的性能,提出了不同方法的选择准则,得出了频域分段滤波方法中的最佳分段长度与系数阶数的关系,显著降低了连续信号FIR滤波的运算量。并提出利用代价函数,综合考虑最佳设计中的吞吐率和处理迟延。 展开更多
关键词 FIR滤波器 频域FIR滤波 最佳分段
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一种面向多维复杂网络的节点传播重要性算法 被引量:2
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作者 张昕 王慧慧 +1 位作者 严沛 郭阳 《计算机科学》 CSCD 北大核心 2019年第S11期348-353,共6页
如何度量节点在网络拓扑结构中的重要程度,一直是复杂网络相关领域中的研究热点。现有的研究大多面向单维网络,针对现实网络结构往往是多维共存的问题,提出了维度相似性的定义来度量各维度间的关系。考虑实际信息传播过程中信息衰减对... 如何度量节点在网络拓扑结构中的重要程度,一直是复杂网络相关领域中的研究热点。现有的研究大多面向单维网络,针对现实网络结构往往是多维共存的问题,提出了维度相似性的定义来度量各维度间的关系。考虑实际信息传播过程中信息衰减对节点重要性的影响,给出传播衰减率的定义,并通过全连接单维网络传播无损假设及对应算法确定衰减系数取值。进一步给出节点重要性的计算方法,在算法中利用复杂网络小世界特性,限定最长传播跳数,使得算法兼顾时间效率与精确度。在真实网络上进行了验证,实验结果表明,与传统的节点度以及节点介数方法相比,该算法在精确度与时间效率方面均具有一定优势。 展开更多
关键词 多维网络 节点重要性 维度相似性 衰减系 传播跳
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