充分条件

Structural Experiment is a basic subject in the Structural Engineering Major, which weighs heavy to the studying researchers on the experimental data accompanied by the former researchers" achievement and lucubration. And the experimental scope is expanding wider, so that making full use of each laboratory"s experimental equipment to conduct the collaborative experiment is also the developing trend. With the rapid development of the computer and network technology, hardware technique has provided the accessible condition for the Structural Experiment, and database technique has offered the convenience and possibility for the experimental results and datas save and data exchange.

结构实验是结构工程专业的一门基础学科，而且随着研究的深入，前人的研究成果，特别是研究试验数据对于继续研究的人员来说有特别重要的意义，并且实验规模也在不断扩大，充分利用各个实验室的实验设备条件进行协同实验也是发展趋势，随着计算机技术以及网络技术的飞速发展，硬件技术都为这一切提供了可行的条件，数据库技术为结构实验提供了保存实验结果、实验数据以及实验数据交换提供了便利和可能。

In this article, based on one-dimension Heisenberg model, the unsymmetric bilayer ferromagnetic and antiferromagnetic thin films are investigated by using the interface rescaling approach under nonperiodic boundary condition.

本文以海森伯模型为基础，只考虑最近邻相互作用，在计入外磁场和非周期性边界条件下，应用界面重参数化方法，分别研究了由A、B两层组成的铁磁或反铁磁层间耦合薄膜中的自旋双链系统的界面自旋波及其存在的充分必要条件，重点讨论了体各向异性场和自旋链长度对界面自旋波存在条件的影响。

We first introduced a new concept called transitive resolvable idempotent symmetric quasigroup, proved that the necessary condition for the existence of TRISQ is also sufficient, then presented a tripling construction for LKTS by using TRISQ instead of TKTS, thus removed the condition "there exists a TKTS" in Denniston''s tripling construction for LKTS; We also improved J. Lei''s product construction for LKTS by removing the condition "there exists a TKTS".

我们首先引入了可迁可分解幂等对称拟群的新概念，证明了TRISQ存在的必要条件也是充分的，然后给出了用TRISQ取代可迁Kirkamns三元系的LKTS的三倍构造法，这样就去掉了在Denniston的关于LKTS的3倍构造中的条件"存在一个TKTS"；我们用TRISQ取代TKTS改进了雷建国的关于LKTS的一个积构造方法，从而去掉了该构造方法中的条件"存在一个TKTS"。

To finding out planning to build background and reason of the rock soil engineering specifications in the field, reconnoitre the rock soil projects of field and foundation, fully understand the project geological condition of building field and foundation, has combined testing, test testing and groundwater water analysis of normal position in the geotechnological sample room.

针对查明拟建场地岩土工程条件的背景和原因，进行场地与地基的岩土工程勘察，充分了解建筑场地与地基的工程地质条件，结合了土工试样室内试验、原位测试试验及地下水水质分析。

In the last chapter, by introducing the isochronous center of real systems into complex planar and defining complex center and complex isochronous center, a concise linear recursion formula for period constants is given, necessary and sufficient conditions of complex isochronous center (the Time-Angle Difference Theorem) proved, conditions of real systems with linearizable center and saddle treated unitedly and the isochronous center conditions discussed fully for a class of real planar cubic systems.

在第七章，通过把实系统等时中心引入复平面研究，定义了复中心和复等时中心，给出了等时中心周期常数计算的简明的线性递推公式，证明了等时中心判定的充分必要条件，统一地处理了实系统具有可线性化的中心和鞍点条件，并对一类实平面三次系统的等时中心条件进行了完整研究。

And for multi-dimension the conditions of the problems with sufficiently regular and star-shaped domain are also given, which have no solutions in Sobolev space.

给出了在空间维数为一时所论问题有无界解的条件，以及在高维空间时，区域充分规则和星形情形下，所论边值问题在Sobolev空间无解的条件。

Characteristic parameters of coal spontaneous combustion were qualitatively studied and quantitatively determined by coal self-ignition experiment from two aspects: coal oxidation and exothermic which is produced by oxidation.

在井下现场应用研究方面，按照安全规程的要求和采空区瓦斯运移规律结合对实际条件下的漏风规律研究存在发火条件的危险区域，通过实验研究，对指标气体产生和发展规律有了充分认识，有效地指导防火灭火工作。

The results of MTT method In vitro culture renal tubular cells showed that the proliferous activity changed from sightly to dramatically intensed in response to fluoride concentration from 0.1mg/L to 15mg/L, but renal tubular cells proliferation obviously decreased in the 25mg F-/L group.

利用生物化学方法检测氧化应激指标，结果表明在钙营养充分的条件下，投氟100mg/L 16周大鼠肾组织GPX活性不是下降而是明显提高，脂质过氧化物变化不明显；低钙饲养条件下投氟100mg/L 16周大鼠抗氧化酶SOD活性亦有明显升高，而GPX却呈降低趋势。

In the study of the Lagrange stability of impact motion, we give some conditions of the bouncing solution of the asymptotically linear equation which is bounded or unbounded. Outside of a large disc, using the symplectic transformation of the Hamilton system to estimate the iteration of the successor map. Applying the Moser's small twist theorem, we get the invariant curves and then give the proof of the bouncing solutions which is bounded. We will estimate the successor map of the equation directly for proving the unboundedness of the bouncing solutions.

在碰撞运动的Lagrange稳定性的讨论中，给出了渐近线性方程碰撞解有界或无界的条件，在充分大的圆盘外，通过Hamilton系统的辛坐标变换的角度平均来估计后继映射的迭代，应用Moser小扭转定理得到不变曲线从而给出在一定条件下碰撞解有界的证明，碰撞解无界性的证明将采用直接估计后继映射的方法给出。

In the part of empirical analysis of Chinese IPO first-day return, the difference between existing study and this study is that we use principal components analysis to extract from five factors to construct investors'sentiment index, add it to controled varibles, on which we examine the influence of offering mechanism on IPO first-day return. Moreover, we gather statistics and compare the IPO holding return for lockup period between fixed-price-class offering method and bookbuilding-class offering method, as well as price range between Chinese A-share market and Hongkong stock market, which prvide comprehensive evidence to appraise Chinese IPO bookbuilding mechanism. 2. Compare to the existing literatures which consider discount or allocation, incentive allocation and discount are considered at the same time in optimal mechanism design in this dissertation, and the offering bottom price is introduced to the price range. We investigate the relationship between price range and allocation quantity, and obtain the optimal price range and allocation strategy so that the advantages of independent allocation are reflected. On the other hand, the disadvantages of independent allocation are reflected in the manipulation in case of no restriction on IPO allocation. To distinguish from the existing literatures, bookbuilding mechanism is introduced to the model. We study the allocation strategy adopted by the underwriter in the pooling equilibrium of manipulation. In addition, we analyze the incentive compatibility conditions to which the existence of pooling equilibrium should satisfy and examine some factors'impact on the existence of manipulation.3. In bookbuilding without independent IPO allocation, Chinese realistic IPO background is considered and the condition of bookbuilding and fixed-price hybrid offering is added. Divide bookbuilding and fixed-price hybrid offering into sequential hybrid and simultaneous hybrid, and point out that the key points of subscription strategy in the two kinds of hybrid are different. Through modeling and simulation we obtain the impact of institutional investors'subscription strategy on bookbuilding without independent IPO allocation, which fill the gap in related research. Moreover, in the part of IPO bookbuilding with over-allotment option, the pricing strategy is divided into hot-IPO strategy and weak-IPO strategy. Take into account the procedure of Chinese IPO with over-allotment option, it presents how the underwriter determines the pricing strategy and what effect it brings to offering price and issue size through modeling and simulation. Therefore, it is instructive as a complement to existing literatures.

此外，对我国A股市场询价发行方式与固定价格发行方式下的IPO锁定期到期时持有收益率、以及我国A股市场与香港市场的询价发行价格区间进行了统计比较，为评价我国IPO市场的询价发行提供了比较全面的依据。2、相比已有文献仅考虑折价和分配中的一种激励措施，本论文在有自主配售权下的机制设计中并用了分配与折价两种激励措施，并且在价格区间的制定中引入发行底价，考察了价格区间与分配量之间的关系，得到最优的价格区间和分配策略，从中体现自主分配权的优点；在有自主分配权下的操纵行为研究中则体现了自主配售权的弊端，与已有文献不同的是，在模型中引入了累计投标询价机制，研究了承销商在混同均衡操纵中采取的分配策略，并对操纵存在的条件进行分析讨论，得出各个因素对混同均衡操纵存在的影响。3、在无自主分配权下的询价发行中，充分考虑了我国实际应用的背景，加入了与固定价格发售混合的条件，并将询价与固定价格混合发行分为序贯与同步两种方式，指出机构投资者在两种情况下申购策略的侧重点各有不同，通过对序贯混合发行方式下的网下累计投标策略以及同步混合发行方式下的资金分配策略的模型建立和数值仿真，考察了机构投资者申购策略对无自主分配权下的询价发行的影响，填补了相关研究文献的空白；在包含超额配售选择权的询价发行中，将发行定价策略分为热销策略和弱销策略，在考虑了我国含超额配售选择权的发行流程下，通过建模以及数值仿真得出承销商会对发行定价策略作出怎样的选取，进而会对新股发行价格、发售数量产生怎样的影响，对目前相关研究的缺乏做出了有益的补充。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。