进行中
- 与 进行中 相关的网络例句 [注:此内容来源于网络,仅供参考]
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Based on the dynamic equation, the transport and acceleration of out-flowing ionospheric ions in the magnetosphere are studied by means of finding the ion distribution function. They include two parts: the study of static ion distribution with analysis and numerical compute; the study of ion acceleration by induced electric feild in the period of dipolarization of taillike geomagnetic lines in the substorm expansion phase with the numerical simulation of the ion distribution function.
本文在磁层中上行离子的加速与传输理论研究领域中,采用动力论方程,用求解离子分布函数的方法来研究问题:(1)用解析求解和数值计算的方法,对上行离子在不同Kp指数条件下磁场位形中的定态分布进行了研究;(2)用数值模拟计算分布函数的方法,对上行离子在亚暴膨胀相磁场向偶极形驰豫过程中受磁尾的感应电场加速进行了研究。
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This thesis investigates the profile extraction and shape optimization on the result of topology optimization of planar compliant mechanisms. The main context includes the following work:(1) summarizing and analyzing the recent research status, some harvest and unsolved problems;(2) analyzing the conceptual design of planar path-generating compliant mechanisms and its mathematical model and tools;(3) Modifying the method of density contour as the method of profile extraction, and developing a method to optimize the density function in the profile extraction according to the requirement of the design of compliant mechanism;(4) developing a method to abstract the compliant mechanism into a form of links and joints by using the principle of connectivity on topology;(5) developing a method of shape optimization of planar path-generating compliant mechanisms, by representing the profile of the abstracted compliant mechanism as simple curves such as straight lines and arcs, establishing the models of the size optimization of the parameters of these curves, so that the compliant mechanism has a machinable shape;(6) At last, proving the feasibleness and effectiveness of the design method by making simulation design and validating it in FEA software.
主要工作包括:(1)分析了柔顺机构拓扑优化和形状优化的研究现状,分析了目前柔顺机构的研究重点、主要成果和尚未解决的问题;(2)分析了基于SIMP的柔顺机构概念设计方法及其相关工具和模型;(3)针对柔顺机构轮廓提取的特殊要求,提出了密度等值线法的改进方案,对密度函数插值点密度值进行优化,提出优化模型和选择优化算法;(4)根据轨迹输出平面全柔顺机构自身的形状特点,提出了轨迹输出平面全柔顺机构的抽象方法,即应用拓扑学上的连通性原理将柔顺机构抽象成杆件和结点形式,并对相应的数学原理进行了证明;(5)提出了平面全柔顺机构的形状还原和尺寸优化方法,对抽象的柔顺机构进行还原,将其轮廓还原成简单曲线的连接,从而建立尺寸优化模型,对机构进行尺寸优化设计,在得到可加工的机构轮廓的同时又能对关键部位进行特别处理;(6)进行了柔顺机构的数值仿真设计,并将所得设计结果导入商用有限元软件中进行仿真实验,证明了设计方法的可行性和有效性。
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After the Dempster-Shafer theory, the DSmT and the neutrosophic theory have been introduced, the multi-source information fusion based on belief assignment has been analyzed in this paper from different points of view, such as the quantitative information fusion and qualitative information fusion, the equally reliable information fusion and inequally reliable information fusion. To extend the fusion technology, the quantitative/qualitative neutrosophic belief assignment and combination rules have been proposed following the connection of DST, DSmT and neutrosophic theory.
本文在对DST(Dempster-Shafer Theory)理论、DSmT理论和中智理论进行了介绍后,从定量信息融合和定性信息融合,等可靠信息融合和非等可靠信息融合等多个角度,对基于信度理论的多源信息融合技术进行了分析,并将信度赋值理论与中智理论相结合,提出了定量中智信度和定性中智信度的表示方法以及组合规则,进一步扩展了信度赋值技术。
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Through designing of composition and structure of the bioactive graded coating,innerstress and its distribution in the coating were analyzed and calculated, the resultsshowed that when composition distribution coefficient n was 1.5, a reasonable stressdistribution could be got, that was at the beginning of deposition the suspension containingrichly BG granules was used so that a rich BG granules layer, a good transitional layerbetween BG layer at the bottom and the coating could be obtained at the titanium alloy side,the bottom of the coating; the stress value near the interface and surface and its character,pressure stress or tensile stress, were decided by the character of its composition itself.Changing composition distribution coefficient n could only change the variation tendency ofstress in the coating, but did not change the stress distribution rule in the coating. Thethinner the coating is, the sharper stress variation in the coating is, which does not mean thatthicker coating is better because the thicker the coating is, the little the permitteddeformation of coating is, so the coating thickness should be thinner, for example, about50μm for bending applications, but for applications only bearing pure shear stress, such asroot of tooth implant, the coating can be thicker little, for instance, about 80~100μm. The study on electrification characteristic and electrophoresis deposition of HAand BG granules in aqueous and non-aqueous solution system found that EPD almost didn'toccur in aqueous solution system. However, because HA granules take position charges inabsolute alcohol, a homogeneous EPD be carried out on the cathode titanium alloy slice, but taking negative charge in absolute alcohol the BG granules not be deposited on the cathode. A guided HA crystallizing, 100~300nm, on surface of the BG granules be realized by metathetical reaction, which cover BG granules with HA microcrystals and make the covered BG granules taking position charges in absolute alcohol, sequentially realize the EPCD of the BG and HA granules on the cathode, so it is feasible to make a titanium alloy/BG/HA bioactive graded coating by making use of EPCD technology. The corrosion experiment of rich boron bioglass coating and plasma spray coating showed that split phase, rich boron and rich silicon phase, occurred during its preparation. In basic medium the corrosion behavior of 〓 BG coating showed uniformity corrosion, the corrosion mostly occurred at rich boron phase area, therefore batch formula design of BGshould avoid the occurring of split phase. The corrosion appearance of plasma spray coatingappeared a non-uniform corrosion, mostly occurred at the edge of the laminated HA moltendrops, and emerged an accelerated corrosion tendency, which will easyly lead to corrosioncrackles extending to the interface and the happening of osmotic interfacial corrosion, thatmay be one of the major reasons leading to the coating cracking-off in the later period. Thetesting results of thermal expansion coefficient of 〓 and 〓BG showed the thermalexpansion coefficient of 〓 BG matched with that of titanium alloy better, and 〓 BG couldsinter with titanium alloy into densification enamel layer at low temperature (720℃).
将Ti6Al4V合金在1000℃下进行真空热处理会降低其力学性能,且合金内的V元素会向表面富集,因此,钛合金真空热处理和表面涂层的烧结温度不能过高,即应低于其相转变点;通过对生物活性梯度涂层的组成和结构的设计,分析和计算了梯度涂层内的应力大小和分布,结果表明:对于本研究,当成分分布系数n=1.5时,可以获得较合理的涂层力学性能,即在沉积开始时,采用富含BG颗粒的悬浮液,以便在钛合金侧获得同底层BG有良好过渡的富BG涂层;梯度涂层界面和表面的应力大小、性质由材料组成本身的性质决定,改变成分分布系数,只能改变涂层内应力变化的趋势;涂层的厚薄不影响涂层内的应力分布规律,但涂层越薄,涂层内的应力变化越快,但这并不意味着涂层越厚越好,因为涂层越厚,涂层允许的变形越小,对于应用于弯曲受力部位的涂层而言,涂层应薄一点为好(50μm);而对于仅纯受剪切应力的部位,如牙根种植体,涂层可适当加厚(80~100μm);通过对HA和BG颗粒在水溶液体系和非水溶液体系中的带电特性和电泳沉积的研究发现,它们在水溶液体系中很难发生电沉积;在无水乙醇溶液中,HA颗粒带正电,可在阴极钛合金片上发生均匀的电泳沉积,而BG颗粒则带负电荷;利用复分解反应法,可以制得100~300nm的HA,通过诱导HA在BG颗粒表面结晶,可对BG颗粒进行表面包覆,获得了被HA包覆的BG颗粒,改变了BG颗粒表面的带电特性,使BG和HA颗粒在无水乙醇中均带上正电荷,从而实现了HA和BG颗粒在阴极上的共沉积。
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objective:to make a comparative analysis of the total saponins content in polygalaceae phloem and xylem parts to guide clinical treatment.methods:we determined the polygalaceae total saponins content at the 575 nm with oleanolic acid as a reference substance and vanillin-perchoric acid as a developer by using uv-visible spectrophotometry.results:the total saponins content of xylem parts was 3.33%,and that of polygalaceae phloem was 0.69%.conclusion:the total saponins content in polygalaceae xylem parts is much more than that of phloem parts,the total saponins in polygalaceae mainly exists in xylem parts.
目的:对远志原药材木部及皮部中总皂苷含量进行比较分析,用以指导临床用药。方法:以齐墩果酸为对照品,香草醛-高氯酸为显色剂,采用紫外-可见分光光度法在575 nm处测定远志总皂苷含量。结果:以此方法对远志木部及皮部中总皂苷含量进行比较、分析,为远志皮部总皂苷含量为3.33 %、木部总皂苷含量为0.69 %。结论:远志中皮部总皂苷含量远远大于木部,远志总皂苷主要存在于根皮中。
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After flow and transient stability calculating of the 330kV grid, we got the over-load and hazard lines set. Then we gained the redundant network needed to be built according to the increasing power supply and load in 2010. Adopting regradation step-by-step algorithm by which we can improve the calculation efficiency , we compared the validity of every line, deleted lines with low validity until no redundant line is in the network. At last we got the target network framework adopting the improved ant colony algorithm. Flow distribution, construction investment assessment and target framework of Gansu long-term planning all be considered, from the viewpoint of to be economic and reliability the feasibility of the improved ant colony algorithm is discussed.
在对2006年该网架结构进行了潮流计算与暂态稳定计算分析后,得出了系统的过负荷与危险线路集,并针对2010年新增的电源和负荷点确定了冗余的待建网架,然后利用逐步倒推法比较各待选线路在系统中的有效性,逐步去除有效性低的线路,直到网络中没有冗余线路为止,以此来以提高优化算法的计算效率,最后利用改进后的蚁群算法确定优化后的目标网架结构,并从潮流分布、建设投资估算等方面与甘肃电网远期规划中确定的目标网架进行了比较,从可靠性和经济性角度论证了改进蚁群算法在网架优化中的可行性。
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But in practical operating, overvoltage caused by reignition of the vacuum switching device frequently appears, and it result in damage of the capacitor bank or the switchgear itself. Ensuring the switchgear against reignition and installing a protective device are two main approaches to avoid the phenomenon. In this paper, a study on overvoltage caused by reignition due to capacitor bank switching with the vacuum switching device and its preventive measures are carried out. The main work which has been done and researches are as follows: 1. The producing mechanism of overvoltage and its influence factor are analyzed. It is pointed out that single-phase reignition is the main reason for damage of the switchgear and two-phase reignition is the main reason for damage of the capacitor bank,so overvoltage of single-phase reignition and two-phase reignition are the emphases of prevention. 2. Analysis of the special working condition of the operating switch for capacitor bank is carried out. It indicates that the vacuum switching device is difficult to realize no-reignition under this operation condition, so it is more practical to adopt protection devices. 3. Analyses of protection effect of RC and MOA and their shortages are carried out. It shows that the two methods can only restrain effectively overvoltage caused by single-phase reignition, and they cannot protect the capacitor bank when reignition of two-phase occurs. 4. The operation principle of G-R damping device is analyzed and discussed emphatically.
本文针对真空开关投切电容器组时因重燃而产生的过电压及其防治措施进行了研究,所开展的主要工作和研究结果如下: 1、对过电压的产生机理及其影响因素进行了分析,指出单相重燃是导致开关设备损坏的主要原因,而两相重燃则是导致电容器组损坏的主要原因,因此单相重燃和两相重燃过电压是防护的重点; 2、对电容器组操作开关的特殊运行条件进行了分析,指出在这种运行条件真空开关难于实现不重燃,因此采用保护装置更具有现实意义; 3、对RC与MOA的保护效果和存在的不足进行了分析,指出这两种方法均只能有效抑制单相重燃过电压,而不能在发生两相重燃时保护电容器组; 4、重点对G-R阻尼装置的工作原理进行了分析和讨论,指出该装置接入后线路中将会出现两种频率的高频振荡,而电容器组上的过电压是由这两种振荡共同决定的; 5、根据对上述两种振荡的分析指出存在一个最佳电阻值使得过电压最低,并提出了电容器组电压和最佳电阻值的近似求解方法; 6、使用电气暂态分析软件MATLAB对G-R装置的保护效果进行了仿真计算,证实该装置确实可以有效抑制重燃时的电容器组过电压; 7、根据仿真与近似计算结果的偏差提出了近似计算的修正方法,经过修正后的过电压计算结果与仿真结果吻合较好; 8、对G-R装置中放电装置G与阻尼电阻R的要求进行了分析,指出采用编织电阻和真空间隙可能是最佳选择。
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objective:to determine total flavonoids content in the leaves of acer saccharum.methods:we determined total flavonoids contents in leaves of acer saccharum by ultraviolet and visible spectrophotometry.results:the flavonoids content was 1.035mg/g in the leaves of acer saccharum.conclusion:the flavonoids content is rich in the leaves of acer saccharum and the leaves have pharmic value.
目的:本文对糖槭叶中的总黄酮含量进行测定。方法:采用紫外-可见分光光度法对糖槭叶中总黄酮含量进行测定。结果:糖槭叶中总黄酮含量为1.035mg/g。结论:糖槭叶中含有丰富的黄酮类化合物,具有可观的药用开发价值。
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Effect of inoculation with phosphate-solubilizing bacteria and soil acidification on the growth of Stylosanthes guianensis Reyan No.2
我国地表水体污染普遍严重,水环境生态质量不断恶化,影响水体正常使用功能;另外,沉积物中磷的再释放是影响水体水质的重要原因,而沉积物中的磷细菌对磷的吸收、贮存和释放在磷循环中起着极其重要的作用,为此本研究针对地表水体水质改善技术及沉积物中磷细菌作用分别进行了研究,并选择在杭州市内河进行了水质改善的技术实践,主要成果如下:(1)在室内模拟条件下,分别设置了高溶解氧7。
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Thist paper chooses 90 groups of "Tong_su_yi_xu synonymic words" from "Modern Chinese dictionary ", and divides them into three kinds according to the interpretation method in the dictionary, regards web page of Sohu website as the platform, us.es the search engine to carry on the search of the word , count the frequency that every group"s word appears , and rejects artificially the mistakes appearing in all web pages that can be opened, language fact presented in observation post then carefully (namely the example sentence with this word appearing in the webpage), and find that the 90 groups of "Tong_su__yi_xu synonymic words" except that the meaning of a word is the same, have quite a few of at frequency of utilization and concrete usage for difference: Because people"s use habit and word use the difference on to cause the appearance frequency of the word analogous to or with a wide gap, because of word-building ability, the word collocates, the word overlaps or the language usually overlaps, linguistic context of area and times , the meaning of a word that the word appears are abstract and concrete, semanteme is laid particular emphasis on, the morphological feature-change, etc.
本文从《现代汉语词典》中选取90组同素异序同义词,按词典中的释义方法将其分成三类,以搜狐网站的网页为平台,运用搜索引擎进行词语的搜索,统计下每组词语出现的频率,并将所有能打开的网页中出现的错误进行人工干预,然后仔细观察所出现的语言事实(即网页中出现的含有该词语的例句),发现这90组同素异序同义词除了词义相同之外,有相当一部分在使用频率和具体的用法上还存在着差别:由于人们的使用习惯和词语使用上的差异造成词语的出现频率相当或者相差悬殊,又因为构词能力、词语搭配、词语重叠或语素重叠、词语出现的区域和年代语境、词义抽象与具体、语义侧重、词性变化等方面的差异造成词语使用上的区别。
- 推荐网络例句
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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)。
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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%。
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However, to get a true quote, you will need to provide detailed personal and financial information.
然而,要让一个真正的引用,你需要提供详细的个人和财务信息。