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The results show that: 1. In the selected four funds, the theoretical risk of three funds is less than that of the actual portfolio fund, and only one fund's risk is higher than that of the actual portfolio fund; 2. It's hard to determine which combination is better between the single exponential model and Markowits'model;.3. Allowing short-selling is better than disallowing short-selling and the optimal solution can not be found under the condition of disallowing short-selling.

结果发现：(1)4只基金中有3只基金的理论模型的风险小于基金实际组合的风险，1只基金的理论模型的风险大于基金实际组合的风险；(2)单指数模型组合与Markowitz模型组合熟优熟劣难以定论；(3)允许卖空组合优于非允许卖空组合，且非允许卖空使得理论模型有时找不到最优解。

The growth of bubble cloud experiences swelling and compressing, reinflating and recompressing, collapsing and falling in the cavitation water jets or abrasive water jets with bubble.

在纯水空化射流与低浓度的磨料射流中，空泡云的发育过程经历了空泡云的膨胀、压缩、再膨胀、压缩、溃灭的几个过程。

The Cavity Monitoring System is used to measure the extent and shape of underground stopes and other cavities.

空区监测系统主要适用于井下采场及空区的动态监测和精密测量，在北美和澳大利亚地区现已成为井下采空区测量和监测的主要手段。

With the help of modern computational fluid dynamics tecnology, this thesis carries on a numerical simulation of annulus multiphase flow of the conventional auger drill stabilizer; it points out the deficiency of the annulus gas in cutting-carrying and lifting; and attempts to develop a drill stabilizer that are suitable for the gas drilling.

本文试图借助现代计算流体力学技术，对常规螺旋钻柱稳定器环空多相流动规律进行数值模拟研究，指出在环空气体携岩举升方面存在的不足，开发一套适合于气体钻井的新型钻柱稳定器，提出全井段环空流场改善方法，实现气体钻井防斜打快，减少冲蚀，提高井眼净化能力的目的。

The litter baskets were empty and the ground was covered with pieces of paper, cigarette ends, old tyres, empty bottles and rusty tins.

废物筐是空的，而满地都是纸片、烟头、旧轮胎、空瓶子和生锈的空罐头盒。

Air swing clamp cylinder/Hydraulic swing clamp cylinder; High pressure swing clamp cylinder/Air jig cylinder; Hydraulic thin-type cylinder/Air lever-t...

空压转角缸。油压转角缸。高压转角缸。空压治具缸。薄型油压缸；杠杆式空压缸。杠杆式油压缸。油压支撑缸。。。

Thus, It becomes very hard for Ling to strike upward to assist Shin while she is going to be attacked by the teeth of sun crow's rods—Ling, yet, knows Shin will be alright by and large so she just gives priority to protect herself by verifying the direction of attacks with hearing.

皇无空冷笑一声，伸出翅膀飞到空中，同时金乌在皇无空身后更高处使出日晖结界，这麼一来，金灵要仰攻协助童心就非常困难，还会受到金乌尖刺攻击—不过金灵知道童心基本上可以无碍，就以听音辨器之术自保为主，不久发现尖刺伤不了金灵的金乌放缓了攻势，金灵便抽空眯眼朝上望去，看见皇无空臂上闪闪发亮的金属支架，突然灵机一动

For the aqueous luminol solution, three absorption bands with maximum. adsorption wavelength λ max 220.7、294 4 and 351.5nm respectively have been detected, with the exception of a little hyperchromic effect, the absorption spectrum contour of the solution cavitated by an ultrasound with a frequency of 1.45 MHz has been certificated to be unchanged.

luminol水溶液的吸收光谱有3个吸收带，它们的最大吸收波长分别是220.7nm、294.4nm和351.4nm，超声空化作用后主要呈弱增色效应，但其吸收光谱的基本形状无明显变化。luminol-NaOH水溶液经超声空化作用后也有较弱的增色效应和减色效应，但不论是否经历超声空化作用，其吸收光谱都与luminol水溶液的吸收光谱相似。

In this article, a series of experiments relating to bubble cloud of cavitating water jets were carried out for different nozzles within different pump pressures and ambient pressures.

本文在不同泵压和淹没压力条件下针对不同类型的空化喷嘴对空化水射流的空泡云长度进行了一系列实验研究。

A series of experiments relating to bubble cloud of cavitating water jet were carried out for different nozzles within different pump pressure s and ambient pressures.

在不同泵压和淹没压力条件下针对不同类型的空化喷嘴，对空化水射流的空泡云长度进行了一系列实验研究。

And Pharaoh spoke to Joseph, saying, Your father and your brothers have come to you.

47：5 法老对约瑟说，你父亲和你弟兄们到你这里来了。

Additionally, the approximate flattening of surface strip using lines linking midpoints on perpendicular lines between geodesic curves and the unconditional extreme value method are discussed.

提出了用测地线方程、曲面上两点间短程线来计算膜结构曲面测地线的方法，同时，采用测地线间垂线的中点连线和用无约束极值法进行空间条状曲面近似展开的分析。