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1.
在经典风险模型的基础上,把索赔到达过程Nt加以推广为更新过程,且认为有干扰的情况下,设其为布朗运动,得到一个新的风险模型:Rt=u ct Wt-∑i=1NtXi,用马尔可夫骨架过程的理论和方法,求得有限时间t盈余的瞬时分布φ(u,t,a),然后求得时刻t的生存概率Ψ(u,t)满足的关系式。  相似文献   

2.
根据量子力学中的线性叠加原理,构造了由多模奇相干态和多模虚偶相干态组成的第Ⅳ种四态叠加多模叠加态光场(|ψ(4)oe,Ⅳ〉q.)利用多模压缩态理论研究了(|ψ(4)oe,Ⅳ〉q,Ⅳ〉q)的等阶N次方H压缩特性.结果发现(1)当压缩阶数N与腔模总数q之积qN为偶数时a.若qN=4m(m=1,2,3,…)时,态(|ψ(4)oe,Ⅳ〉q)处于等阶N-H最小刻测不准态.b.若qN=4m′+2(m′=0,1,2…),且(q∑j=1Nψj=±kψπ)(或±kψπ+π/2)(kψ=0,1,2,…)时,态(|ψ(4)oe,Ⅳ〉q)呈现"半相干态"效应2)当qⅣ=2p′+1(p′=0,1,2,…)时,态(|ψ(4)oe,Ⅳ〉q)可呈现以下三种状态a.当(q∑j=1 Nψj=±kψπ)(kψ=0,1,2,…)时,第一正交分量可呈现等阶N次方H压缩效应.b、当(q∑j=1Nψj=±kψπ+π/2)(kψ=0,1,2,…)时,第二正交分量可呈现等阶N次方H压缩效应;c."半相干态"效应.  相似文献   

3.
多时滞Logistic差分方程正周期解的存在性   总被引:4,自引:0,他引:4  
本文研究多时滞Logistic差分方程u(k 1)=u(k)exp│a(k)-∑j=1mbj(k)u(k-τj(k))}运用重合度理论,证明了方程至少存在一个正周期解.  相似文献   

4.
根据量子力学中的线性叠加原理,构造了多模奇相干态和多模虚偶相干 态组成的第Ⅳ种态叠加多模叠加态光场|ψ^(4)oe,Ⅳ&;gt;q.利用多模压缩态理论研究了态|ψ^(4)oe,Ⅳ&;gt;q,Ⅳ&;gt;q3的等阶N次方H压缩特性,结果发现:(1)当压缩阶数N与腔模总数q之积qN为偶数时:a.若qN=4m(m=1,2,3,…)时,态|ψ^(4)oe,Ⅳ&;gt;q处于等阶N-H最小刻测不准态。b.若qN=4m′+2(m′=0,1,2,…),且q/∑/j=1Nψj=&;#177;kψπ(或&;#177;kψπ+π/2)(kψ=0,1,2,…)时,态|ψ^(4)oe,Ⅳ&;gt;q呈现“半相干态”效应,2)当qN=2p′+1(p′=0,1,2,…)时,态|ψ^(4)oe,Ⅳ&;gt;q可呈现以下三种状态:a.当q/∑/j=1Nψj=1=&;#177;kψπ(kψ=0,1,2,…)时,第一正交分量可呈现等阶N次方H压缩效应,b、当q/∑/j=1Nψj=&;#177;kψπ+π/2(kψ=0,1,2,…)时,第二正交分量可呈现等阶N次方H压缩效应;c.“半相干态”效应。  相似文献   

5.
本文重点研究了形如1|p j=f j(u j),u∑j=1uj≤,chains|∑wjcj型在链不可中断的情况下连续型问题的算法及其算法复杂性,分别讨论了p j=f j(u j)是线性函数、非线性函数的情况,给出了最优排序和最优资源分配及其稳定点的定义,同时证明了由此所求出的资源分配u*确系最优资源分配.  相似文献   

6.
考虑了一类有如下形式的对称统计量Tn=k(n-k) k(k-1)2-1∑n-ki=1∑i kj=i 1φ(Xi,Xj) ∑n-1i=n-k 1∑nj=i 1φ(Xi,Xj),这里φ(Xi,Xj)为一对称函数,其中k为不大于n的自然数.这一表达形式是一类统计量,当k=n-1时,它就是一U统计量.在假定E(φ2(Xi,Xj)≤M<∞下,研究了Tn的强相合性.  相似文献   

7.
研究了一类具非线性扩散系数和阻尼项的双曲型偏微分方程系统(a)2u1(x,t)/(a)t2+m(t)(a)u1(x,t)/(a)t=ai(t)hi(ui)△ui+n∑j=1aij(t)hij(u1(x,t-τj(t)))△ui(x,t-τj(t))-m∑k=1bik(x,t)uk(x,t-σ(t)) (x,t)∈Ω×R+≡G,i=1,2,…m,获得了该方程组在Robin边值条件下解振动的充分条件.  相似文献   

8.
利用多模压缩态理论,研究了由多模复共轭相干态|{zj(a)*}〉q=|{Rj(a)exp(-iψj)}〉q和多模虚相干态|{±izj(b)*}〉q=|{±iRj(b)exp(-iψj)}〉q的线性叠加所组成的两类非对称多模量子叠加态|ψ±(2)〉q在各个模的压缩阶数全为偶数即Nj=2pj=1,2,3,……q,pj=1,2,3,……)的条件下的偶数次不等幂次Nj次方Y压缩效应.结果发现:如果各个模初始位相ψj以及态|{zj(a)*}〉q和|{±izj(b)*}〉q之间的初始相位差θpq(R)-θnq(I)与各个对应模的振幅Rj(a)和Rj(b)的乘积的总和q∑j=1Rj(a)Rj(b)所组成的混合初始相位[(θpq[R]-θnq(I))-+q∑j=1Rj(a)Rj(b)]分别满足一定的条件时,态|ψ±(2)〉q总可呈现出周期变化的偶数次不等幂次Nj次方Y压缩效应.当pj均为奇数时可获得较大的压缩深度.  相似文献   

9.
多时滞Logistic差分方程正周期解的存在性   总被引:1,自引:0,他引:1  
本文研究多时滞Logistic差分方程u(k+1)=u(k)exp{a(k)-∑mj=1bj(k)u(k-τj(k))}运用重合度理论,证明了方程至少存在一个正周期解.  相似文献   

10.
本文给出由就范正交系{ψn(x)}^∞n=1包含L^p(E)构成的正交级数∞/∑/n=1anψn(x),其系数an收敛于零的充分条件及由此得到在L^2([0,1])上的推论,本文也给出当p∈(0,2)时结论不成立的反例。  相似文献   

11.
《海外英语》2007,(5):44-45
It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,  相似文献   

12.
The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity.  相似文献   

13.
一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/  相似文献   

14.
《海外英语》2007,(5):10-11
Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?  相似文献   

15.
《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.  相似文献   

16.
王菲 《华章》2007,(12):273-273
Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.  相似文献   

17.
裴水妹 《华章》2007,(11):196
Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.  相似文献   

18.
19.
1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…  相似文献   

20.
风的曲线     
Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose.  相似文献   

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