Minimal Enclosing of an MPT （v,λ） in a TS （u,λ＋1）

Let MPT (v,λ) denote a maximum packing of triples of order v with index λ and TS (u,λ) denote a triple system of order u with index λ. In this paper, for v≥6, we determine necessary and sufficient condition for enclosing an MPT (v,λ) in a TS (v m,λ 1) with index λ increased by 1 and minimal increase in extra points.     

Minimal Enclosing of an MPT （v,λ） in a TS （v＋l,μ）

Let MPT (v,λ) denote a maximum packing of triples of order v with index λ and TS (u,λ) denote atriple system of order u with index λ. In this paper, for v≥6, we determine necessary and sufficient conditions forenclosing an MPT (v，λ) in a TS (v l ,λ m) with one extra point and minimal increase in λ.     

Splitting Balanced Incomplete Block Designs with Block Size 2×k

IntroductionIn the study of authentication codes,Ogata,etal[1] ,introduced the concept of splitting balancedincomplete block design which can be used toconstructk- splitting A- codes.A ( v,u× k,λ) - splitting balanced incompleteblock design is a pair( V,B) ,where V is a v- setofpoints and Bis a collection of subses of V ( calledblocks) with size uk such that the followingconditions are satisfied:( 1 ) Every B∈ B is expressed as a disjointunion of u subblocks of size k:B=B1∪ B2 ∪ ...…     

The Dimensions of Graphs and Constructions of Their Bases

IntroductionGraph G,considered in this paper,is finiteand simple with vertex set V ( G) and edge setE( G) .Let d( x,y) denote the distance between xand y in G and W={w1,w2 ,…,wk}denote the or-dered set of V( G) .For any given v∈V( G) ,therepresentation of v with respect to W is the k- vec-tor:r( v| W) ={d( v,w1) ,d( v,w2 ) ,…,d( v,wk) }.The ordered set W is called a resolving set of G ifr( u| W) =r( v| W) implies that u=v for all pairs{u,v}of vertices of G. A resolving set of G with…     

ON THE EXISTENCE OF THE h-RESTRICTED EDGE CONNECTIVITY OF A GRAPH

IntroductionLet G=(V,E) be a finite,simple and undi-rected graph with vertex set V and edge set E.We' ll follow the terminology and notation of Ref.[1 ]and terms not defined here can be found inRefs.[1 ,2 ].A set S of edges of G is called an edgedisconnecting set if G - S is disconnected. Theusual edge connectivityλ(G) of G is the minimumcardinality over the all edge disconnecting sets ofG.Note that,in the above definition,absolutelyno conditions or restrictions are imposed either onthe…     

On the Existence of (v,3×3,λ)-Splitting Balanced Incomplete Block Design with λ between 2 to 9

Let (v, u × c, λ)-splitting BIBD denote a (v, u × c, λ)-splitting balanced incomplete block design of order v with block size u × c and index λ. The necessary conditions for the existence of a (v, u × c, λ)-splitting BIBD are v ≥ uc, λ(v-1) ≡ 0 0 mod (c(u-1)) and λv(v-1) ≡ 0 mod (c2u(u-1)). In this paper, for 2≤λ≤9 the necessary conditions for the existence of a (v,3×3,λ)-splitting BIBD are also sufficient with one possible exception for (v,λ)=(39,9).     

FAST IMAGE ENCODING ALGORITHM BASED ON MEAN-MATCH CORRELATION VECTOR QUANTIZATION

Introduction　　 Vector quantization (VQ) is an importanttechnique for image compression,and has beenproven to be simple and efficient[1,2 ] .Signal com-pression is achieved in VQ by using a codebookwith relatively few codevectors compared to thenumber of possible signal vectors. VQ can beviewed as a mapping from k- dimensional Euclideanspace Rk into a finite subset C of Rk.We call thisfinite set C the codebook and,moreover,C={ci|i= 1 ,2 ,… ,N},where ci is a codeword and N is thecodeboo…     

关于正则图的最大特征值的一个不等式

主要讨论了Krivelevich的与图的谱有关的一个不等式的等号成立的情况,得到下面的结果:定理1:设G=(V,E)是n个顶点的d正则图,令d=λ1≥λ2≥Λ≥λn是G的所有特征值.又令λ=max2≤i≤n|λi|,则对于U,W(∪)V,有|e(U,W)-d|U‖W|/n|≤λ√|U‖W|(1-|U|/n)(1-|W|/n),其中e(U,W)表示U到W的边数;等号成立当且仅当U=W,且G|e(U,W)-d|U||W|/n|或者为具有参数(n,k,a,a)的强正则图,或者为完全图.     

NIR Hyperspectral Imaging Measurement of Sugar Content in Peach Using PLS Regression

Near infrared (NIR) hyperspectral imaging measurement of sugar content in peach was introduced. NIR spectral images (650～1 000 nm, resolution: 2 nm) of peach samples were captured with developed hyperspectral imaging setup. Partial least square (PLS) regression prediction model was developed to estimate the sugar content in peach; step-wise backward method was utilized to determine optimal wavelength subsets. Experimental results show that the calibration model with optimal wavelength subsets has a correlation coefficient of prediction of 0.97 and a standard error of prediction of 0.19, the prediction accuracy is higher than the calibration model applied over the whole wavelength, which proves that variable selection plays an important role in improving the prediction accuracy of PLS regression model.     

RP-HPLC method for the quantitation of β-Sitosterol in Elaeagnus Gon yanthes Benth

Objective To establish an RP-HPLC method for the determination of β-Sitosterol in Elaeagnus Gonyanthes Benth. Methods The separation was performed on a luna C8 (2) (150 mm×4.6 mm, 5μm) column with the mobile phase of methanol-water (88∶12, v/v) at a flow rate of 1.0 mL/min, the detection wavelength was set at 210 nm, and the temperature of the column was maintained at 35 ℃. Results The calibration curve of β-Sitosterol was linear over the concentration range of 0.075-0.375 mg/mL (r=0.9999) and the average recovery of β-Sitosterol was 96.30% with RSD of 3.60%(n=3). Conclusion The method is simple, rapid, and accurate, and can be used for the quality control of Elaeagnus Gonyanthes Benth.     

与任意图(m,r)-正交的(g,f)-因子分解

设G是一个图,用y(G)和E(G)表示它的顶点集和边集,并设g(x)和f(x)是定义在V(G)上的两个整数值函数,且对C每个x∈V(G),有5/2r-1≤g(x)≤f(x),则图G的一个支撑子图,称为G的一个(g,f)-因子,如果对每个x∈V(G),有g(x)≤d,(x)≤f(x)．图G的(g,f)-因子分解是指E(G)能划分成边不交的(g,f)-因子,设F=|F1,F2,…,Fm|和H分别是图G的因子分解和子图,若对所有1≤i≤m有|E(H)∩E(Fi)|=r,则称,和H(m,r)-正交．本文证明：若G是一个(mg m-1,mf-m 1)-图,H是G中任一有mr条边的子图,则G有一个(g,f)-因子分解与H(m,r)-正交。     

关于θ-图的邻点可区别全染色

u，v两点间连三条内部不相交的路且至多有一条长度为1的图，称为θ-图．设G是阶至少为2的连通图，k是正整数，f是V(G)∪E(G)到{1，2，3，…，k}的映射，对任意u∈V(G)，记C(u)={f(u)}∪{f(uv)|uv∈E(G)，v∈V(G)}．如果：1)对任意uv，vw∈E(G)u≠w，有f(uv)≠f(vw)；2)对任意uv∈E(G)，有f(u)≠f(v)，f(u)≠f(uv)，f(v)≠f(uv)；3)对任意uv∈E(G)，有C(u)≠C(v)，那么称f为G的k-邻点可区别全染色(简记为k-AVDTC)，称min{k|G有k-邻点可区别全染色}为G的邻最可区别全色数，记作Xat(G)．本文得到了θ-图的邻点可区别全染色。     

Predicting the Dielectric Strength of c-C4F8 and SF6 Gas Mixtures by Monte Carlo Method

An improved Monte Carlo method was used to simulate the motion of electrons in c-C_4F_8 and SF_6 gas mixtures for pulsed townsend discharge. The electron swarm parameters such as effective ionization coefficient, [AKα-] and drift velocity over the E/N range from 280～700 Td(1Td=10-21 V·m2) were calculated by employing a set of cross sections available in literature. From the variation cure of [AKα-] with SF_6 partial pressure p, the limiting field (E/N)_lim of gas mixture at different gas content was determined. It is found that the limiting field of c-C_4F_8 and SF_6 gas mixture is higher than that of pure SF_6 at any SF_6 mixture ratio. Simulation results show excellent agreement with experiment data available in previous literature.     

皇冠图Gn,m的邻点可区别边色数

定义皇冠图Gn,m为V（Gn,m）={ui|i=1,2,…,n}∪{vi|i=1,2,…,n|∪i=1 m|uij|j=1,2,…,m},E(Gn,m)={u1u2,u2u3,…u2u1}v1v2,v2v3,…vnv1}∪{u1vi|i=1,2,…,n}∪i=1^n{∪i=1^n{uijij|j=1,2,…,m}∪i=1^n{uijui(j 1|j 1,2,…|j=1,2,…,m-1}),(n≥3,m≥1）。本文得到了Gn,m的邻点可区别边色数。     

均衡二分图中含有大圈的2-因子的度和条件

设G=(V1,V2;E)是一个二分图,满|V1|=|V2|=n sk 1足,其中s 4,k 1是两个正整数.定义G中不相邻两点的最小度和为σ2(G)=min{dG(u) dG(v)∶u,v∈V(G),uv E(G)}.在这篇文章中,我们证明了如果σ2(G)2「(1-1s)n﹁ 2,则G有一个2-因子包含k个长至少为2s的点不交的圈     

Announcement

Journal of Shanghai Jiaotong University ( English edition) ,sponsored by Shanghai Jiaotong Uni-versity,was established in1 996.As of December,2 0 0 3,the Journal has issued8volumes having1 6issues. Itis hereby announced that,with approval of the Ministry of Education of China,the Journalwill be distributed as a quartery from the first issue of2 0 0 4 and its new serial title is Journal ofShanghai Jiaotong University ( Science) .The Journal is an academic publication focusing on natural…     

C23n,C24n邻点可区别的全染色

设G(V，E)是阶数不小于2的简单连通图，n是自然数，V∪E到{1，2，…，k}的映射f满足Vuv∈E(G)，f(u)≠f(v)，f(u)≠f(uv)≠f(v)；А↓uv,uw∈E(G),(v≠w)，f(uv)≠f(uw)；А↓uv∈E(G),G(u)≠C(v)．其中C(u)=f(u)∪{f(uv)|uv∈E(G)}．，f称为G(V,E)的一个邻点是可区分的全染色法，简记为k-AVDTC.其中最小的k称为G的邻点可区别的全色数。G^2是G再加上G中点间距离为2时连边后的图．本文得到了3n、4n阶圈C3n^2，C4n^2邻点可区别的全色数。     

关于Cm·Sn和Cm△Sn的全染色

设m≥3,n≥2V(Cm·Sn)={ui|i=1,2,…,m}∪{vij|i=1,2,…,m;j=1,2,…,n},E(Cm·Sn)={u1u2,u2u3,…,u(m-1)um,umu1}∪{uivij|i=1,2,…,m;j=1,2,…,n} 则称Cm·Sn为m个Sn(星)的心联图.V(CmΔSn)={ui|i=1,2,…,m}∪{vij|i=1,2,…,m;j=1,2,…,n},E(CmΔSn)={v11v21,v21v31,…,v(m-1)1vm1,vm1v11}∪{uivij|i=1,2,…,m;j=1,2,…,n} 则称CmΔSn为m个Sn(星)的沿联图.本文给出Cm·Sn和CmΔSn全染色以及全色数.     

关于Cm·Sn和CmΔSn的全染色

设m≥3,n≥2V(Cm.Sn)={ui|i=1,2,…,m}∪{vij|i=1,2,…,m;j=1,2,…,n},E(Cm.Sn)={u1u2,u2u3,…,u(m-1)um,umu1}∪{uivij|i=1,2,…,m;j=1,2,…,n}则称Cm.Sn为m个Sn(星)的心联图.V(CmΔSn)={ui|i=1,2,…,m}∪{vij|i=1,2,…,m;j=1,2,…,n},E(CmΔSn)={v11v21,v21v31,…,v(m-1)1vm1,vm1v11}∪{uivij|i=1,2,…,m;j=1,2,…,n}则称CmΔSn为m个Sn(星)的沿联图.本文给出Cm·Sn和CmΔSn全染色以及全色数.     

F-Decomposition of Noetherian Modules over Hyper-（Cyclic or Finite）Groups

Let F be a locally defined formation consisting of locally soluble groups，G a hyper-(cyclic or finite)locally soluble group and A a noetherian ZG-module with all irreducible ZG-factors being finite，G∈F,f(∞)≌f(p)，f(P)≠Фfor each P∈π．The following conclutions are obtained：(1)if there exists a maximal submodule B of A such that A／B is F central in G and B has no nonzero F centml ZG-factors，then A has an F decomposition；(2)if there exists an irreducible F central submodule B of A such that all ZG-composition factors of A／B are F ecentric，then A has an F decomposition．