查询词典 elementary chain

Different from the case of strict minimal siphons in a net system, the number of elementary ones is bounded by the smaller of place count and transition count. Based on the ideas mentioned above, this thesis proves that the set of elementary siphons is not unique, while different ones may lead to different control results.

本文在此研究的基础上，论证了网系统中的基本信标的不唯一性，控制不同的基本信标可以得到不同的控制效果，进而提出了最优基本信标的概念并给出了相应的计算方法，应用这一计算方法可以在多项式时间内求得一组最优基本信标，也就是说，控制该组基本信标相对于其他的基本信标可以使得系统Petri网模型具有最多的可达状态，这在实际中，意味着系统具有更大的灵活性。

As a foundation, the definition of elementary integral transformation and the method to factorize an integral matrix with elementary integral transformation is proposed firstly. After that, the problem how to find identification vectors in Modular-S-invariants is solved.

文中首先给出初等整数变换的概念，之后借助初等整数变换对整数矩阵进行分解，并在此基础上给出从加模S-不变量中求取不可达见证向量的方法。

This paper discusses such problems which are easily solved incorrectly in limitedteaching as, segment function is uncertain not to be elementary function, elementary function is un-certain to be continuous in its field of definition, unlimited variable is uncertain to be infinity, theinfinitely many infinitesimal is uncertain to be infinitesimal, the multiplication of two non- infinitesi-mal is uncertain not to be infinitesimal.

1分段函数不一定不是初等函数我们知道初等函数的定义是：常数和基本初等函数经过有限次的四则运算或复合，用一个解析式表示的函数叫初等函数。教材中的定义强调的"有限次"和"一个解析式"，使很多同学产生"非有限次"和"非一个解析式"的函数就不是初等函数的误解。例1f=ceox，s xx！0为分段函数，但也可以表示为f=e12(x-x2")+cos12(x+x2#"$)-1，故为初等函数。

From the filter bed a desulfurized gas is withdrawn, whose content of elementary sulfur is not more than 30 percents of the content of elementary sulfur when entering the filter bed.

从过滤床排出脱过硫的气体，它们的元素硫含量不大于进入过滤床时的元素硫含量的30％。

The home says in Ms. Wang Zhen of Han Yang, her son is going up this year first 3, the achievement when original elementary school all the time pretty is good, go up namely game of online sth resembling a net is confused to bring about achievement to glide point-blank after junior high school, so she objects network game taking elementary school teaching material to the utmost,"Child cent is not clear right with the fault, once guide bad easy addiction ".

家在汉阳的汪珍女士说，她儿子今年正上初三，本来小学时成绩一直蛮好的，就是上初中后迷上网络游戏导致成绩直线下滑，所以她极力反对网络游戏进小学教材，"小孩分不清对与错，一旦引导不好就容易上瘾"。

The new class changes under the implementation, this article through carries on the investigation, the research to the Huaian Elementary school intermediate grade student homework situation, understood the nowadays elementary student homework the practical situation, proposed the following suggested:(1) transformation teaching idea, reduces the student to bear.

新课改实施下，本文通过对淮安市小学中年级学生家庭作业情况进行调查、研究，了解现今小学生家庭作业的切实情况，提出以下建议：（1）转变教学观念，减轻学生负担。

Precession and nutation of top and gyrosscope is discussed by elementary method,equations of motion are solved using simplified models, and an elementary analysis is made.

用初等方法讨论了陀螺与陀螺仪的进动及章动，用简化模型求解了运动方程，并给出了它们的初等分析。

By applying elementary transformation,this paper obtains a new method to search for a normal orthogonal basis in Euclid space, it also gives a procedure by which the fewer third elementary transformations are enough to realize this method.

导出用初等变换法求Euclid空间的标准正交基的方法，并进一步获得了只需进行较少次数的第三种类型的初等变换就能实现这一方法的结果。

The purpose is to discuss under the reform of Grade 1-9 Curriculum, the current pre-policy and actual performance of the development on teacher's profession in elementary schools, as well as the analysis and evaluate the current situation of the participance of professional activities from teachers in elementary schools, for further plan the need of future professional development activities.

本研究的主要目的，在於探讨九年一贯课程改革之下，国小教师专业发展的当前措施、实际成效与实施困难，同时分析与评估国小教师参与专业发展活动之现况，进一步规划其未来专业发展活动的需求。

Contents: A Brief Review of Elementary Quantum Chemistry; An Introduction to Electronic Structure Theory; The Born-Oppenheimer Approximation; Time Evolution of Wavefunctions; Angular Momentum Summary; The Unitary Group Form of the Hamiltonian; Introduction to Hartree-Fock Theory; Permutational Symmetries of Integrals; Notes on Excited Electronic States; The Quantum Harmonic Oscillator; Assigning Symmetries of Vibrational Modes; Notes on Elementary Linear Algebra

内容： 初等量子化学的简评；电子结构理论的介绍；天生奥本海默的接近； Wavefunctions的时间演化；角动量摘要； Hamiltonian的单位的组形式；哈特里-Fock 理论的介绍；积分的Permutational对称性；在令人激动的电子国家上注明；这台量谐波振荡器；分配振动的方式的对称性；在初等线性代数上注明

We are forbidden from giving money to these shoeless, skinny children, as this will perpetuate begging.

向光着脚，骨瘦如柴的孩子施舍是不可以的，因为要招来无休无止的乞讨。

It would be hard not to fall victim to some sharpeyed policeman.

要想不被某个目光锐利的警察抓到，谈何容易。