中值定理的“中间值”的渐近性

本文的定理A比文献(2)减少了条件——f~((n p))(x)在点a处连续。这样,由定理A就可推出文献(1)及(3)的各个定理。 定理A 若f~((n p))(a)≠0(n≥1,p≥1),f~((n j))(a)=0(1≤j相似文献   

风云一号遥感器可见光通道大气程辐射之间的关系

本文利用光谱辐射计测量的大气程辐射资料,研究了相应于“风云一号”卫星上改进型甚高分辨率扫描辐射计(CAVHRR)4个可见光通道的大气程辐射量(N_a)之间的关系。结果表明它们满足((N_a(λ))/(N_a(λ_0)))=A(λ/λ_0)~B的关系。 经回归分析得:A为1.0887,B为3.6587。式中λ_0是CAVHRR第二通道的中心波长,即λ_0=0.875μm,λ是CAVHRR其他3个通道中心波长。     

一类时滞微分方程的渐近性(英文)

本文讨论如下时滞型微分方程解的渐近性: u~(n)+f(t,u(t_0(t)),u′τ_1(t)),…,u~(n-1)(τ_(n-1)(t)))=0, (E)其中τ_i(t)≤t,lim τi(t)=∞,i=0,1,…,n-1,且 |f(t,u_0,u_1,…,u_(n-1))|≤sum from i=0 to n-1 φ_i(t)g_i(|u|/τ_i~(n-i-1)(t))或 |f(t,u_0,u_1,…,u_(n-1))|≥sum from i=0 to n=1 ψ_i(t)h_i(|u|/τ_i~(n-i-1)(t)) 我们关心如下两个问题: (P_1)方程(E)的所有解满足u~(n-i)(t)/t~(i-1)→α_i当t→∞,且(E)有解使得α_i≠0,i=1,2,…,n-1; (P_2)对任意的多项式sum from i=1 to n-1 (k_i/i_!)t~i,方程(E)存在一个解u(t)使得u~(m)(t)-sum from i=m to n-1 (k_i/(i-m)_!)t~(i-m)→0当t→∞,m=0,1,…,m。我们得到了一些使(P_1)及(P_2)成立的充要条件和必要条件。     

一类序同态的构造

作者定义了从L_1~X到L_2~Y的映射σ,证明了σ是满足σ(x_λ~0)=σ(λ)∧σ(x_(I_1)~0)的保并映射的充要条件是σ(A)=∨g(λ)∧f(Aλ),其中f为X到L_1~Y的映射,g为L_1到L_2~Y的保并映射,且有f(X)≤g(I_1);最后证明了一类序同态的分解定理,它们是前人相应结果的推广与补充。     

2017年春季季风间期南海中北部浮游植物生长与微型浮游动物摄食

Phytoplankton growth rates and mortality rates were experimentally examined at 21 stations during the 2017 spring intermonsoon(April to early May) in the northern and central South China Sea(SCS) using the dilution technique, with emphasis on a comparison between the northern and central SCS areas which had different environmental factors. There had been higher temperature but lower nutrients and chlorophyll a concentrations in the central SCS than those in the northern SCS. The mean rates of phytoplankton growth(μ_0) and microzooplankton grazing(m) were(0.88±0.33) d~(–1) and(0.55±0.22) d~(–1) in the central SCS, and both higher than those in the northern SCS with the values of μ_0((0.81±0.16) d~(–1)) and m((0.30±0.09) d~(–1)), respectively.Phytoplankton growth and microzooplankton grazing rates were significantly coupled in both areas. The microzooplankton grazing impact(m/μ_0) on phytoplankton was also higher in the central SCS(0.63±0.12) than that in the northern SCS(0.37±0.06). The microzooplankton abundance was significantly correlated with temperature in the surface. Temperature might more effectively promote the microzooplankton grazing rate than phytoplankton growth rate, which might contribute to higher m and m/μ_0 in the central SCS. Compared with temperature, nutrients mainly affected the growth rate of phytoplankton. In the nutrient enrichment treatment,the phytoplankton growth rate(μn) was higher than μ_0 in the central SCS, suggesting phytoplankton growth in the central SCS was nutrient limited. The ratio of μ_0/μn was significantly correlated with nutrients concentrations in the both areas, indicating the limitation of nutrients was related to the concentrations of background nutrients in the study stations.     

罗兰C系统导航定位计算中的奇异现象及分析研究

算例一:设某一船只位于我国罗兰C系统东海台组的左侧基线延长线附近,其地理坐标为P(φ:10°00′N,λ:113°30′E),该点至三岸台的大地距离分别为S_1=1560054.877m,S_2=2398108.765m,S_3=3126522.685m,化算到地心球面上得到球面距离差α_1=-7°.528238688,α_2=6°.543342783,试将该点的大地距离差采用地心球面迭代法反解该点的船位大地坐标,并比较其计算船位的精度。     

A model for wave growth in fetch-limited conditions

In this paper, it is held that the universal relationships of wave growth in fetch-limited conditions , i. e.,(f|~) p=A(x|~)-Band (m|~)0= C(x|~) Dshould satisfy the Toba 3/2 power law and the wave energy balance equation. In the ideal generation situation, theoretically it can be derived that the ideal fetch-limited wave growth relationship should have D=3B and D B =1, (i.e., B = 0.25, D = 0.75 ) and A3C=2. 1×l(T4C~(1/2)_d , where Cd is the drag coefficient. The 3/2 power law, the wave energy balance equation and the decrease of wave steepness with increasing fetch have became three requirements which should be satisfied by fetch-limited wave growth algorithms. A semi-empirical and semi-theoretical model for fetch-limited wave growth is presented. In the application to the slanting wind situation an un(?)ersal relationship of dimensionless wave energy vs dimensionless peak frequency is presented and the comparisons show that the model is in good agreement with observations.     

McMullen函数族的六个结论

前人研究表明,对有理函数R_λ(z)=z~2+λ/(z~3),当正参数λ充分小时具有6个性质。本文应用临界点临界值理论和Riemann-Hurwitz公式等多种理论,发现对一般的McMullen函数族R_λ(z)=z~n+λ/(z~m),其中(1/n)+(1/m)1且λ∈C-{0},当|λ|充分小时同样的6个结论也成立。     

湖北道观河水库青梢鲌(Culter dabryi)的个体生殖力

于2001年4、5月份,从道观河水库中随机采集青梢鲌成熟雌体53尾,用鳞片鉴定年龄(A),测量了体长(L)、体重(W)、净体重和性腺重(Wo)等形态学指标,计数个体绝对生殖力(F),并计算出青梢鲌的体长相对生殖力(FL)、相重相对生殖力(FW)、肥满度(CF)和成熟系数(GSI)等,用8种数学模式及多元回归方程拟合了青梢鲌个体生殖力与形态学指标间的关系。结果表明,青梢鲌样本由1 —4 龄鱼组成;其个体绝对生殖力与体长、体重和年龄分别呈抛物线、幂函数和幂函数相关,相关式分别为:F=-1.032 0.00754L2(n=53,R2=0.6920,P<0.01),F=0.0287W0.911(n=53,R2=0.7315,P<0.01),F=0.339A1.489(n=53,R2=0.6211,P<0.01);体长相对生殖力与体长、体重和年龄分别呈对数函数、对数函数和直线相关,相关式分别为:FL=-4995.579 2001.462lnL(R2=0.7315,n=53,P<0.01),FL=-1869.419 622.496lnW(R2=0.7315,n=53,P<0.01),FL=-71.679 6323.410A(R2=0.7315,n=53,P<0.01);体重相对生殖力均值约219粒/g,变幅主要为150—300粒/g;多元逐步回归分析其绝对生殖力和体长相对生殖力均与多个指标密切相关,相关式分别为:F=-1.248 0.070GSI 0.0571L×W(n=53,R2=0.8212,P<0.01),FL=-1050.940-26.756W 46.031Wo 97.941L×W(n=53,R2=0.7243,P<0.01);而体重相对生殖力仅与成熟系数有相关性:FW=144.186 8.222GSI(n=53,R2=0.3246,P<0.01)。     

南海北部冬、夏季浮游群落呼吸率

Plankton respiration is an important part of the carbon cycle and significantly affects the balance of autotrophic assimilation and heterotrophic production in oceanic ecosystems. In the present study, respiration rates of the euphotic zone plankton community(CR_(eu)), size fractionated chlorophyll a concentration(Chl a), bacterial abundance(BAC), and dissolved oxygen concentration(DO) were investigated during winter and summer in the northern South China Sea(n SCS). The results show that there were obvious spatial and temporal variations in CR_(eu) in the n SCS(ranging from 0.03 to 1.10 μmol/(L·h)), CR_(eu) in winter((0.53±0.27) μmol/(L·h)) was two times higher than that in summer((0.26±0.20) μmol/(L·h)), and decreased gradually from the coastal zone to the open sea. The distribution of CR_(eu) was affected by coupled physical-chemical-biological processes, driven by monsoon events. The results also show that CR_(eu) was positively correlated with Chl a, BAC, and DO, and that BAC contributed the highest CR_(eu) variability. Furthermore, the results of the stepwise multiple linear regression suggest that bacteria and phytoplankton were the dominant factors in determining CR_(eu)(R~2 = 0.82, p0.05) in the n SCS. Based on this relationship, we estimated the integrated water column respiration rate(CRint) within 100 m of the investigated area, and found that the relationship between the biomass of the plankton community and respiration may be nonlinear in the water column.     

邛海湖盆形态研究

邛海是四川省第二大淡水湖泊,本研究是为更好地利用和保护该人类资源所做的基础研究工作之一。通过基于GPS-RTK技术以及测深仪的水下地形测量,结合原有历史资料,应用湖沼学理论,对邛海的湖盆形态进行定量化研究。经研究,邛海为南北长、东西宽湖体较为接近半球体形式的断陷湖泊,正常高水位(1510.3m)下最大水深18.80m,平均水深10.63m,湖长10.85km,湖面最大宽度5.24km,平均宽度2.53km,岸线长37.4km,湖面面积27.408km2,湖底真面积27.411km2,容积291.43×107m3。研究结果对邛海流域的深入研究及保护与开发提供了基础信息支持。     

东山湾贝类养殖容量的估算

以初级生产力为基础，应用营养动态模式和沿岸海域能流分析模型，估算东山湾贝类年生产量分别为269331t和295767t，平均282549t。扣除潮间带、潮下带和吊养区浮筏、随着基及延绳上附着的非养殖滤食性附着动物自然现存量35760t，贝类可养殖量为246789t。应用统计分析和逻辑斯谛种群增长模型估计贝类可养面积为11839hm^2，其中缢蛏635hm^2，石蛎1160hm^2,吊蛎1525hm^2，翡翠贻贝633hm^2，菲律宾蛤仔1154hm^2，扇贝698hm^2，江瑶248hm^2，泥蚶601hm^2，巴非蛤4151hm^2，凸壳肌蛤1034hm^2。1998年实际养殖面积和养殖产量分别为10581hm^2和220564t。尚有1258hm^2,26225t的扩大开发潜力。文中还讨论了合理布局和优化养殖结构问题。     

1998～1999年南极中山站气象要素变化特征

本文主要根据1998～1999年南极中山站气压、气温、相对温度和风的观测资料，对其周边地区气象要素变化特征进行了分析．结果表明，中山站地区近期降温倾向明显，气温年较差大；空气干燥，相对湿度小；复半年受下降风影响大；帘年盛行东风，风力较强．其气候具有明显的大陆性特征。     

SMAP卫星海表盐度产品精度评定与全球海表盐度特征分析

海表盐度是研究海洋变化及其气候效应重要的物理量。本文将2018年SMAP卫星的月均、日均海表盐度产品分别与Argo月均网格化产品、实时散点盐度数据进行比较,评定其精度,并分析全球海表盐度分布特征。结果表明：SMAP卫星月均产品RMSE为0.17,BIAS为0.11,STD为0.17,R为0.98,t检验呈显著相关;SMAP卫星日均产品RMSE为0.28,BIAS为0.23,STD为0.26,R为0.81,相较月均产品,精度较低。SMAP卫星月均产品偏差在中纬度海域较小,在高纬度海域较大;SMAP卫星日均产品偏差在太平洋海域为-0.6~0.6,在地中海海域超过1.0。全球海表盐度在25.0~40.0之间,沿纬度方向呈带状分布,其中大西洋海表盐度普遍高于太平洋和印度洋。     

海底沉积物取样的扰动机理研究

海底沉积物取样技术对大洋诸多科学研究来说非常重要,各种研究目标的实现与沉积物样品的质量息息相关.在使用常规管状取样器对松软或轻微固结的沉积物取样时,沉积物样品的扰动总是不可避免的.以机械手持式沉积物取样器为原型机,建立了管状取样器的取样过程模型,分析了沉积物样品的扰动机理;采用球形孔扩张理论获得了沉积物土体受到取样管挤压扩张的理论解;结合太平洋具体沉积物土体物理力学参数,对管状取样器取样造成沉积物扰动的状况给出了一个定量描述,并且提出取样管壁的厚度是减小沉积物扰动的关键参数.     

热带气旋对南海各海区影响程度的诊断

根据１９４９—１９９２年南海热带气旋资料，分为厄尔尼诺年和非厄尔尼诺年，将南海划分成４个海区，采用灰色聚类方法，找出特征值Ｎ。然后，用这Ｎ值诊断厄尔尼诺和非厄尔尼诺年在南海的热带气旋对４个海区的影响程度。     

大地坐标的严密解算与精度分析

基于纬度计算的严密公式,使用高斯牛顿法,直接对大地坐标的纬度值进行求解,过程易于理解,计算结果精确,同时给出了纬度对大地高精度的影响公式,分析纬度的变化对大地高解算精度的影响程度。     

福建沙埕港八尺门潮汐电站开发研究

本文叙述了八尺门潮汐电站的开发。该电站处于缺煤缺油而潮汐能源丰富的地区,其坝址位于峡谷处,海床为基岩。采用预制浮这沉箱结构,以无围堰施工。这是我国首例用该技术建设潮汐电站,将为我国大型潮汐电站和低水头常规水电站提供经验。     

基于多时相遥感数据的海岸线自动提取方法

海岸线是海洋的重要组成部分,对于海域管理具有重要意义.本文根据岸线位置确定原理,即将多时相瞬时水边线上边界近似作为海岸线,提出了一种基于多时相水边线的海岸线自动提取方法,该方法应用区域生长与边缘检测相结合的方法提取瞬时水边线,然后采用海岸线自动判别算法进行海岸线的提取.首先计算归一化水体指数(normalized di...     

缘管浒苔5.8SrDNA及其转录间隔区的序列测定及分析

利用PCR扩增、克隆和测序的方法对青岛市红岛虾池生长的缘管浒苔(Enteromorpha linza)的5.8S rD-NA及其转录间隔区ITS序列进行了分析,并依据ITS序列构建了浒苔属不同种之间的进化树。结果表明,获得了核糖体DNA完整的ITS和5.8S rDNA序列,ITS1为195 bp,5.8S rDNA为155 bp,ITS2为184 bp,总长度GC含量为63%。缘管浒苔与浒苔和曲浒苔的序列差异百分率较小,分别为2.4%和4.6%,与(U.olivascens)的序列差异百分率最大,为16.7%。Kimura-2参数遗传距离结果表明缘管浒苔和浒苔的遗传进化关系较近。