一类具有特殊曲率性质的(α,β)-度量

在一般的(α,β)-度量F=αφ(s)与Riemann度量α的Ricci曲率之间的关系基础上,证明了一类特殊的(α,β)-度量F=α~2/α+β南,在维数n≥3的流形上,如果F具有速向的Ricci曲率,且β是闭的1-形式,则其Ricci曲率等于零.从而得到如果F=α~2/α+β具有常Ricci曲率,并且β是闭的1-形式,则其Ricci曲率等于零.

Abstract：

We studied an important class of(α,β)-metric on the basis of the relationship of Ricci curvature between G1and a Gi.We verified that if F=α~2/α+β on an n dimension manifold M(n≥3)is of istropic Ricci curvature,i.e.Rmm=(n-1)c(x)F~2,where c(x)is a scalar function on M and β is closed 1-form,then c(x)=0.Hence,we obtained that if F=α~2/α+β is of constant Ricci curvature and β is closed,then c(x)=0.     

一类抽象半线性泛函微分方程的小时滞鲁棒稳定性

研究Banach空间X中的抽象半线性泛函微分方程d/dtx(t) = Ax(t)+F(t, x_t(·))的小时滞鲁棒稳定性,其中无界线性算子A在X上生成一个C0-半群T(t)_t≥0, F是非线性函数.在F是全局Lipschitz连续的条件下,利用算子半群理论以及扰动方法,证明了上述方程的解的指数稳定性对小时滞是鲁棒的.

Abstract：

The robust stability of the abstract semi-linear functional differential equationd/dtx(t)= Ax(t)+F(t, x_t(·))is considered in Banach space X, where the linear operator A generates a C_0-semigroup [T(t)]_t≥0in X, and F is a nonlinear function. Under the condition that F is globally Lipschitz continuous, and the robust stability of the above equation is proved with the operator semi-group theory and perturba-tion method.     

Cytological Evaluation and Karyotype Analysis in Plant Germplasms of Elytngia Desv.

Elytrigia Desv. is widely distributed throughout the world and is represented with species of various levels of ploidy including diploids, tetraploids, hexaploids, octaploids, and decaploids. The distribution pattern of these ploidy levels, however, is not well-defined. In this study, the levels of ploidy for 64 accessions of Elytrigia from 25 countries were determined with microscopic procedures. The results showed that accessions of E. intermedia and E. repens were grouped into three distinct levels of ploidy including diploids, tetraploids and hexaploids. For E. elongata, E. pontica, and E. caespitosa, it was found that two ploidy levels presented, and only one ploidy level was in those of E. hybrid, E. pycnantha, E. pungens, E. juncea, and E. alatavica. Karyotype analysis indicated that the karyotype formula of diploid, tetraploid and hexaploid of E. intermedia was 2n = 2x = 14 = 6m ＋ 6sm ＋ 2st, 2n = 4x = 28 = 2M ＋ 10m ＋ 16sm and 2n = 6x = 42 = 4M ＋ 18m ＋ 20sin, respectively. Furthermore, the karyotype formula of three germplasms in tetraploid of E. intermedia was 2n=4x=28 =2M＋ 10m＋ 16sm, 2n=4x=28=4M＋22m （sat）＋2sm and 2n=4x=28 =4M＋ 12m＋ 12sm （sat）, which were not completely uniform. Therefore, it could be suggested that the studies about chromosome constitution would be helpful for the detail understanding of the diversity of germplasm resource in Elytrigia and promoting the utilization in the crop molecular breeding.     

弱条件下马氏链收敛速度的界

以m-骨架(m≥1)代替1-骨架,计算出马氏链Ф的几何收敛速度的界,从而推广了已有结论.

Abstract：

Assume that φ is a time-homogeneous discrete-time Markov chain with m-skeleton φm on the state space [0, ∞). Meyn and Tweedie have studied the bounds on convergence rates of Markov chains φ with conditions of 1-skeleton. This paper is an attempt to weaken those conditions, that is, it manages to change 1-skeleton into m-skeleton. At the same time, it calculates the bounds on geometric convergence rates of Markov chain φ with weak conditions of m-skeleton (m ≥ 1) in order to generalize the result ofM-eyn and Tweedie.     

一类具有迷向Ricci曲率的(α,β)-度量

研究了一类具有迷向Ricci曲率的(α,β)-度量F=(α+β)~2/α,得到这类(α,β)-度量在n(n≥3)维流形上具有迷向Ricci曲率的充分必要条件.从而证明了在n(n≥3)维时,若这类(α,β)-度量具有常的Ricci曲率,则它的Ricci曲率为零.

Abstract：

In this paper,we consider the Finsler metric F =(α+β)~2/α,which has istropic Ricci curvature.We obtain the sufficient and necessary conditions for it to have istropic Ricci curvature on an n-dimension(n ≥ 3)manifold M.Then we prove that if such a Finsler metric on an n-dimension(n ≥3)manifold M has constant Ricci curvature,its Ricci curvature is zero.     

某个映象族的公共不动点定理

设K是完备度量空间(x,d)的一个非空子集,f:K→K是单值映象,Fi:K→B(K)(i∈I)是一族集值映象.在某些条件下,证明了f,Fi(i∈I)在K中有唯一公共不动点存在.

Abstract：

Suppose K is a non-empty subset of the complete metric space (X, d), f: K → K is a singlevalued mapping, and Fi: K → B (K)(i ∈ I) are a family of set-valued mappings. Under different conditions, we prove the existence of common fixed points of f, Fi(i ∈ I) in K.     

基于度量的SPTO实施模型与方法

将软件度量与软件项目跟踪与监控活动联系在一起,提出了一个完整的基于度量的SPTO过程实施模型,围绕该过程模型研究了项目跟踪与监控的实施方法,使软件企业能够更高效的理解、控制和改进软件项目开发.

Abstract：

Software project tracking and oversight (SPTO) is an important component of the software process management, and the key of it is how to carry on the effective tracking and analysis of the project.This paper proposes a complete implementation model based on measurement: SPTO process model. Surrounding this model, we thoroughly study the implementation methods of SPTO.     

Photosynthetic Responses of A New Grapevine Variety ‘Xinyu’ in Turpan

Turpan is one of the major high-quality grape production bases in the world for years because its climate is so special (hot, dry, and windy). The grape market needs the varieties with high yield, quality, and environmental adaptability. ‘Xinyu’ is a new variety bred by crossing selection of E42-6 (a self-pollinated inbred of Vitis vinifera cv. ‘Red Globe’) as female and Vitis vinifera cv. ‘Rizamat’ as male parents and registered in the Crop Varieties Registered Commission of Xinjiang Uygur Autonomous Region in 2005. In this study, we determined the impacts of environmental factors on its photosynthesis. The results showed the climate in Turpan was characterized by long-time intensive sunshine, high temperature and relatively low humidity. The peak value of photosynthetic available radiation (PARi) was 1 454 μmol·m^-2·s^-1, and the minimum and average values were 111 μmol·m^-2·s^-1and 938.889 6 μmol·m^-2·s^-1, respectively. Air temperature and sunlight intensity reached the highest values during 1 p.m. to 4 p.m. Net photosynthetic rate (Pn) of Xinyu increased stably before 11 a.m. and there was a midday depression during 11 a.m. to 2 p.m. The minimum value of Pn appeared at noon (2.77 μmol·m^-2·s^-1). It was concluded that as a new grape cultivar, “Xinyu” could withstand extreme climate conditions in Turpan.     

Density of Standing of Plants at Cultivation of Cauliflower Seeds in Uzbekistan

The results of researches aimed to establish the optimum growing space and density of standing of plants at cultivation of cauliflower seeds in Uzbekistan are stated in the article. Researches were spent in the suburb of Tashkent with a mid-early grade ＂Domestic＂. In experiences were compared 5 densities of standing （31746, 35714, 40806, 47620 and 57142 pieces/hectare） received at planting of sprouts with row-spacing of 70 sm and distance between plants in a row 25, 30, 35, 40 and 45 sm. Experiences were pawned in quadruple frequency with the area of an allotment 10 M2. 60-65 day sprouts were planted under film tunnel shelters on February 11-12. Film shelters were kept over plants till the end of March. Seed plants were grown up without formation. Experiences were accompanied by phonological control, calculation of leaves quantity, an establishment of average weight of a head, definition of quantity of the plants, which have given seeds, the account of a crop of seeds from a bush and of a unit of area. It has been defined that reception of seeds of a cauliflower at cultivation under film tunnels is quite possible in Uzbekistan. It is established that with representation of the big growing space the plants form more leaves, earlier and larger form the heads, develop the testicles acceleration and increase their seed efficiency. It has been revealed that the more plants thickness is, the bigger share of them does not give seeds. In this connection the greatest crop of seeds has been received at growing space 70x45 sm at which 31.7 thousand Pl/ha had been planted. It is proved that in the conditions of Uzbekistan it is possible to cultivate high-grade seeds of cauliflower with productivity of 127-147 kg/ha.     

碰撞分支Q-矩阵生成的Markov积分半群

首先证明了碰撞分支Q-矩阵在Banach空间l∞上能生成一个积分半群T(t),且当m1≤0时它的生成元是Q∞,当m1＞0时它的生成元是Qo**.事实上,T(t)是一个Markov积分半群.然后论证了当m1＞0时,T(t)满足Feller性质.

Abstract：

This paper aims to prove that the collision branching q-matrix can generate an integrated semigroup T(t)on l∞ and that if m1 ≤ 0, its generator is Q∞; if m1 ＞ 0, its generator is Qo** . In fact, T(t) is just a Markov integrated semigroup. Also, we obtain that if m1 ＞ 0, this integrated semigroup has the Feller property.