Hammerstein型非线性积分方程解的存在性

该文采用化为积分方程组的方法 ,利用锥上不动点指数计算 ,在不要求非线性项 f (x,u)非负的情况下 ,证明 Hammerstein型非线性积分方程 φ(x) =∫Gκ(x,y) f (y,φ(y) ) dy非平凡解和多解存在性的一些新的结果。此结果可用来证明非线性常微分方程两点边值问题解的存在性。     

黄、渤海水温垂直结构数值预报方法的研究 Ⅱ.二维数值预报模式

文中根据黄、渤海区水温资料建立了无维深度η和无线温度θ_T以及相应的水温垂直剖面的相似函数θ_T=f(η).在此基础上,设:上均匀层厚度h=h(x,y,t)、表层水温T_s=T_s(x,y,t)、上均匀层以下的温度T_z=T_s(x,y,z,t)、底层温度T_H=T_H(x,y,t)、流速分量u=u(x,y,t)、v=v(x,y,t)和海面起伏ζ=ζ(x,y,t),提出了水温垂直结构的二维数值预报模式,模式的求解是用“ADI”和“HN”法进行.文中引列了预报时效为4天的试报结果,效果是令人满意的.     

论NLA模式的静力初始化

近来,不仅由于NLA(数值有限区域)模式的正规波初始化仍是一个未解决的问题,而且由于非线性正规波初始化收敛性问题和平衡方程解的不存在问题之间已有的关系,静力初始化已经引起了许多科学家的注意。这篇论文给出了NLA原始方程模式(6层,水平分辨率150公里,55×48个网格点)静力初始化的一些结果。作了预报地区上空非椭园面积的初始化试验,这一试验考虑了减小的网格宽度和由模式预报的移动的天气尺度. 在气压坐标系中,非线性平衡方程为: 同时ψ(x,y)=g(x,y) (x,y)∈D(2)式中D为矩形面积,g(x,y)由边界D函数确定,剩下的符号是众所周知的。     

一类种群竞争模式的定性分析

本文对J.Maynard Smith提出的物种竞争模式: x=x(a-bx-cy-kxy) y=y(e-fx-gy-lxy)作了定性分析,并给出两物种共存或其中任一物种死亡,而另一物种趋于确定值的条件。     

一类非线性微分方程的非平凡解

本文讨论了一类非线性二阶常微分方程 (um+ 1(x) )″+(x- 1) p(x) u′(x) =0 ;x∈ (0 ,1],m>0 ,非平凡解的存在问题 ,用非线性算子方法证明了非平凡解的存在性以及惟一性。从而使W.OKRASINSKI发表于《数学分析与应用》的论文“一类非线性常微分方程的非平凡解”中的部分结果成为本文的 1个推论。     

养殖远海梭子蟹的形态学变化观察

在温度29.5±1℃和盐度30条件下,将远海梭子蟹1期龄幼蟹人工养殖成15期龄蟹.结果表明:198.1d蟹蜕壳14次,成活率为10.8%;蟹平均蜕壳时间间隔从2.6d逐渐延长至32d;平均体重从0.003g增至67.324g,平均体重增长率为61.8%～170%,蜕壳增长率随着幼蟹发育而下降,但蜕壳体重绝对增长量随着幼蟹发育而增加.平均甲长从1.75mm增至45.87mm;平均甲宽从2.28mm增至81.79mm.各发育期甲宽、甲长比为1.30～1.86.甲宽和甲长与体重呈指数关系,甲宽(y)与体重(x)关系式为y=2.244 6e0.252 7x;甲长(y)与体重(x)关系式为y=1.603 8e0.231 5x;甲长(y)与甲宽(x)呈线性关系,关系式为y=1.805x.     

一类种群竞争模式的定性分析

本文对J．Maynard Smith提出的物种竞争模式：x=x(a-bx-cy-kxy) y=y(e-fx-gy-lxy)作了定性分析，并给出两物种共存或其中任一物种死亡，而另一物种趋于确定值的条件。     

闽-粤东族大黄鱼生长性状的相关与通径分析

研究大黄鱼各形态性状对体重的影响,测定了272尾7月龄闽-粤东族大黄鱼的全长(x1)、体长(x2)、头长(x3)、眼后头长(x4)、躯干长 (x5)、体高(x6)、尾柄长(x7)、尾柄高(x8)和体重(y),计算相关系数,采用通径分析方法计算了以体重(y)为依变量、其它性状为自变量的通径系数和决定系数.结果表明:全长、体长、头长、眼后头长、躯干长、体高、尾柄长、尾柄高和体重两两之间的相关系数均达到极显著水平(P<0.01);头长对体重的直接影响(0.429)最大,其次分别为体长(0.242)、躯干长(0.136)、体高(0.113)和尾柄高(0.079),全长、眼后头长和尾柄长对体重的直接影响不显著(P>0.05).剔除直接影响不显著的自变量建立的以体重为依变量的多元线性回归方程为(y)=-4.676 0.374×2 2.270×3 0.503×5 0 .519×6 1.254×8,其决定的数为0.940.     

二阶微分方程解的渐近性的讨论

考虑如下的二阶方程 其中X(t,x,)是定义在域H:{0≤t< ∞,-∞0,n>0,f(t)为连续函数,f(t)≠0下讨论了方程(X)的不同类型解的渐近性态,给出了各种渐近解存在的充分必要条件。     

红壳色文蛤选育子代各壳色的形态分化及养殖效果的比较

以红壳色为目标性状,于2009年进行了文蛤(Meretrix meretrix)的群体选育研究,建立了红壳色选系子一代(Fl),对子一代壳色种类、分布频率及其数量性状进行了统计、测量和分析,并对各壳色的形态、生长速度做了研究.结果表明,文蛤壳色具有多态性,红色、黄色、白双、黄双、波纹的分布频率分别为75.58%、8.55%、0.53%、14.83%、0.50%.红壳色亲本的子代中出现红色∶花色=3∶1,符合孟德尔遗传模式.聚类分析与欧氏距离矩阵结果表明,文蛤波纹与黄色遗传距离最近,白双与黄双遗传距离相近,与红壳色的遗传距离最远.主成分分析显示白双文蛤与黄双文蛤在空间分布上相对重叠,波纹文蛤与黄色文蛤具有较高的重叠率,而红壳色文蛤相对分散,从而进一步说明5种壳色文蛤的遗传距离关系.经过1a同池养殖,子代壳长多数已达到10～30 mm,红壳色文蛤的日生长率为0.20%,花壳色文蛤的日生长率为0.18%,且红壳色文蛤的相对比较生长速度比花壳色文蛤快10.41%.红壳色文蛤选育子代的壳长与壳宽、壳高、粒重存在一定的回归关系.红壳色文蛤壳长对壳宽、壳高、粒重的回归方程分别为:y1=0.502 4x1-0.556 0(R2=0.992 0)、y3=0.8103x3+0.620 0(R2=0.995 6)、y5=0.000 3x25.9029(R2=0.991 9),花壳色文蛤壳长对壳宽、壳高、粒重的回归方程分别为:y2=0.495 3x2-0.419 2(R2=0.990 9)、y4=0.798 5x4+0.793 5(R2=0.995 6)、y6=0.000 4x26.845 8(R2=0.993 4).研究结果为文蛤的红壳色定向选育奠定了理论基础.     

测度微分方程解的渐近性

研究非线性测度微分方程Ｄｘ＝Ｆ（ｔ，ｘ）Ｄｕ解的渐近性质，方程中的导数是分布意义下的导数．     

多孔介质中两相可压缩可混溶驱动的GALERKIN方法

多孔介质中两相可压缩可混溶驱动问题由一对耦合的非线性方程来描述.Douglas在忽略弥散效应的情况下,讨论了该方程的半离散Galerkin求解方法,并得到了解的最优的L2模误差估计.文章讨论了在考虑弥散效应的情况下该方程的半离散Galerkin方法,并得到了饱和度方程解的最优L2模误差估计.     

P(x)-Laplace方程正径向解的唯一性定理

本文给出了一类p(x)-Laplace方程的正径向解在单位球上的1个唯一性定理,文章中假定p(x)是径向的单调函数．并且非线性项满足某种单调性条件。     

甲醛对Nessler法和次氯酸酚盐法测定养殖水体总氨氮的影响

水体中含一定浓度的甲醛 ,用 Nessler法测得的总氨氮 (TAN)浓度远远高于实际浓度 ,差异百分数最高达 4 5 0 .0 6 % ;用次氯酸酚盐法测得的总氨氮 (TAN)浓度则明显低于实际浓度 ,差异百分数最高可达 84 .77%。甲醛浓度范围为 10～ 4 0 mg/ L、TAN浓度为 1～ 10 mg/ L,通过双因素有重复观察值的交叉实验 ,得到如下矫正式 :(1)用 Nessler法测 TAN时 ,Y=4 .0 5 2 9- 0 .0 72 4 x1+ 0 .2 0 6 4x2 ,标准误差为 1.3381;(2 )用次氯酸酚盐法测 TAN时 ,Y=0 .1196 + 0 .0 345 x1+ 1.0 0 2 2 x2 ,标准误差为 0 .4 6 2 7。 Y为 TAN实际浓度 (mg/ L) ,x1为甲醛浓度 (mg/ L) ,x2 为测得的 TAN浓度(mg/ L )。比较含氨氮水体与不含氨氮水体中的甲醛浓度 ,方差分析结果表明 ,没有显著差异。     

红树植物秋茄次生木质部生态解剖学的比较

本文研究了不同纬度秋茄（Ｋａｎｄｅｌｉａ ｃａｎｄｅｌ）次生木质部的组织结构及数量特征。秋茄的导管多为梯纹导管。随着纬度的升高,温度下降,各分布区导管分子长度和导管直径呈现下降的真挚深圳福田的秋茄导管分子长度、导管直径均是最大是个例外＿;穿孔板横隔的数目也纬度的升高而减少;盐度高（３３）造成福建云霄竹塔的秋茄低导管颁布频率、低单管孔率、低双管孔率;秋茄的射线分布频率随着纬度的升高而减少（海南东寨港     

Seawater Intrusion in Semi-Closed Convergent Estuaries (Case Study of Moroccan Atlantic Estuaries): Application of Salinity Analytical Models

Salinity is an important parameter influencing the water quality of estuaries, and can constitute a serious problem to society due to the need for freshwater for industry and agriculture. Therefore, the determination of salt intrusion length in estuaries is a challenge for managers as well as scientists in this field. The managers tend to use simple and reliable tools for salinity variation. Although 2-D and 3-D numerical models are common tools for the prediction of salinity intrusion now, analytical models of salinity variation are much more efficient, and also require minimal sets of river data. In this paper, two analytical solutions, Brockway and Savenije used worldwide to assess longitudinal salinity variation in alluvial estuaries, are applied to the Moroccan Atlantic semi-closed estuaries, i.e., Sebou and Loukkos. The solutions are derived from salt convection-dispersion equations, with different assumptions for the dispersion coefficient. The estuaries' bathymetry is described by an exponential function. The performance of these two solutions was evaluated by comparing their results with field-measured salinity data. The Brockway model's salinity predictions performs well to observations especially in downstream reaches of the two estuaries (Sebou: R² = 0.95, root mean square error [RMSE] = 1.50‰, normalized root mean square error [NRMSE] = 3.45‰; Loukkos: R² = 0.95, RMSE = 1.13‰, NRMSE = 3.01‰), while the Savenije model outperformed the Brockway's model and is better to predict salt intrusion length and salinity variation along the two estuaries (Sebou: R² = 0.97, RMSE = 1.15‰, NRMSE = 2.85‰; Loukkos: R² = 0.98, RMSE = 0.95‰, NRMSE = 1.94‰). This revealed that both analytical solutions apply well to the estimation of salinity variation and the prediction of salt intrusion in these two estuaries.     

The evolution of isolated vortices interacted with steep slope

Numerical solutions are examined for isolated, intense vortices as influenced by western bounding bottom topography through the use of a rigid-lid, two-layer primitive -plane numerical model. Systematic studies are made of the sense of rotation (cyclonic/anticyclonic), the consequence of varying the gradient of bottom slope, and the different vertical shear in a two layer ocean. In the basin with a bottom slope, the nearly barotropic anticyclonic vortex forms a modon-like vortex for S with fixedRo ₂<O(1) (where is the ratio between the variation of the Coriolis parameter across the eddy to the Coriolis parameter in the center, S the topographic effect and,Ro ₂ the Rossby number in the lower layer) and its generation is due to a compound effect of the planetary beta, topographic beta, avvection, and mirror image. The formation of the modon-like vortex and the propagation of the original vortex onto the bottom slope depends on the strength of slope gradient and the baroclinicity of the vortex. The nearly barotropic anticyclonic vortex evolves into the stronger upper ocean one with increasing S: the gradient of the bottom slope becomes steeper. Then the original vortex lives longer because the barotropic component of the energy is converted to the baroclinic one and it moves toward southeast in forming a modon-like vortex in the lower layer. The evolution of a vortex in the model results are compared to observational results of a Kuroshio warm core ring (KWCR) obtained from hydrographic data (June, 1985) and from NOAA satellite infrared images (April, 1985 to July, 1985). It is shown that a KWCR (June, 1985) is influenced by the western continental slope/shelf of the East Japan.     

Collisions Between Lumps/Rogue Waves and Solitons for A (3+1)-Dimensional Generalized Variable-Coefficient Shallow Water Wave Equation

In this paper, we investigate a (3+1)-dimensional generalized variable-coefficient shallow water wave equation, which can be used to describe the flow below a pressure surface in oceanography and atmospheric science. Employing the Kadomtsev-Petviashvili hierarchy reduction, we obtain the semi-rational solutions which describe the lumps and rogue waves interacting with the kink solitons. We find that the lump appears from one kink soliton and fuses into the other on the x−y and x−t planes. However, on the x−z plane, the localized waves in the middle of the parallel kink solitons are in two forms: lumps and line rogue waves. The effects of the variable coefficients on the two forms are discussed. The dispersion coefficient influences the speed of solitons, while the background coefficient influences the background’s height.