ppl-空间的遗传性

对ppl-空间的遗传性质进行了探讨．获得的主要结果是：1）ppl-空间的开遗传性蕴禽遗传性;2）ppl-空间具有F,遗传性;3）完备的ppl-空间具有遗传性．     

Wppl-空间的一个性质

H．Z．Hdeib在文[1]中定义了wppl-空间，并研究了几种拓扑空间的关系，本文对wppl-空间进行了探讨，并得到wppl-空间的一个性质：在H1紧空中，wppl-空间是Lindeloef-空间。     

强ppl-空间及其性质

依据强ppl-空间的理论，证明了仿紧空间是强ppl-空间；强ppl-空间是meta紧空间；强ppl-空间被完备映射的逆象所保持．     

wppl-空间的遗传性的一个注记

对wppl-空间进行了研究,获得两个结果:1)空间[0,ω1)不是meta-Lindelof空间;2)wppl-空间不具有遗传性.     

Banach空间上凸函数的一致可微性

1987年J.M.Borvein和D.Preiss对凸函数的Frechet可微性和Gsteaux可微性的定义给予了推广。本文在以上工作基础上定义了β—可微空间和弱β—可微空间,并主要讨论了弱β—可微空间。对β—可微空间的讨论参看(3).     

Mazur空间的特征

一个局部凸空间 ,若其上每一个列连续线性泛函是连续的 ,则称为Mazur空间 .文中给出Mazur空间的特征 ,讨论了Mazur空间与C 序列空间的关系 ,得到如下结果 :设 (X ,T)是一个局部凸空间 ,则以下结论是等价的 :1) (X ,T)是Mazur空间 ;2 )T+ (与T有相同收敛序列的最强的局部凸拓扑 )是相容拓扑 ;3) (X ,T)中每一个列开的半空间是开的 .     

论鲁迅小说中的鲁镇空间

鲁镇作为鲁迅小说中反复出现的一个意象,早已超越了静止的建筑或故事的叙事空间背景而成为了一个有"意味"的空间,事实上,鲁迅笔下的"鲁镇"世界,集中展示了当时广大乡村(市镇)在变革前夕的愚昧麻木、陈腐闭塞、封建落后的普遍面貌.本文从空间文化的角度对鲁镇的公共空间、私性空间进行分析,明确了这两种空间的地理特征和文化内涵,同时...     

试析教育叙事之空间维度

一、源远流长:空间理论的发展社会理论对空间问题的关注,早见散轶于涂尔干、马克思等理论家的论著中,70年代列斐伏尔等地理学家论述了社会关系与空间的相互建构,列斐伏尔在《空间的生产》中提出了社会空间这一概念,认为空间是一种社会产品,可以分为物理空间(自然)、心理空间(空间的话语     

Meta-Lindelof空间的性质

对meta-Lindelof空间的性质进行了探讨.给出了X是meta-Lindelof空间的一个等价条件:X的每一开覆盖ψ都有点可数的加细覆盖 ,使对每一个x∈X,x∈Int(st(x,v));证明了meta-Lindelof空间被可数对一开映射保持;在可分空间中meta-Lindelof空间与Lindel6f空间等价.     

“魔方游戏”案例——跨越“魔墙”

—、玩具介绍(―)玩具构成“魔方游戏”是一款包含空间感知、空间记忆、空间推理、空间表征等知识经验,能够促进幼儿空间认知能力发展的益智玩具。它由64块魔方(表面为红'黄、蓝3种颜色)、90张不同系列范例卡组成。     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

不同的吃喝玩乐

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/     

漏洞百出的教育

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?     

Western and Eastern culture differences in commercial field

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.     

只要努力,不要后悔

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.     

浅谈移民问题

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.     

Sister Carrie, an Adherent of Desires

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.     

Improvement of one-cycle controller by use of proportional integral differential controller

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

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.