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为了更好地进行6R型机器人轨迹的规划和工作任务的拟定,使用SolidWorks的虚拟样机技术插件COSMOSMotion对拟定的6R型机器人工作任务进行逆过程仿真,得到了相关运动参数,为机器人的物理机工作轨迹规划提供了可行性数据。该种基于SolidWorks平台的机器人逆过程仿真方法能为机器人的轨迹规划快速提供运动参数,提高设计质量,缩短设计周期,使得并行设计的优势得到充分的发挥。  相似文献   
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This paper examines the performance of three fluid phase equations of state in predicting the available very high-pressure data of n-pentane, n-hexane, cyclohexane, toluene, dichloromethane, chloroform and methanol. It is assumed that the key for success at such pressures is establishing the appropriate interrelation between the densities of saturated liquids and the imaginary infinity pressure states. The recently proposed EOS that combines SAFT with the cohesive term of cubic EOS (SAFT + Cubic) most likely satisfies this criterion. According to this model, the saturated liquid densities at Tr = 0.4 are approximately 2.1 ± 0.1 times smaller than the densities predicted at the infinity pressure. With this ratio SAFT + Cubic yields reliable density estimations as far as the substances remain liquid (stable or metastable) in all the considered cases. Its pressure limit for accurate predictions of the auxiliary properties such as sound velocities and bulk moduli appear to be lower, typically around 1 GPa.  相似文献   
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由于SW6-93(SW6-1998)软件包没有双管板换热器管板的计算模块,因此在设计计算时,我们将双管板换热器分成几个单管板换热器进行计算。几年来设计了数十台固定双管板换热器(卧式、立式)和U形管双管板换热器,下面介绍分解模式。  相似文献   
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介绍了C波段驻波电子直线加速管的研制情况.该加速管采用2.5 MW脉冲磁控管为微波功率源,脉冲宽度4μs,重复频率250 MHz.可提供能量为6 MeV和9 MeV两档能量的电子束,工作频率为5712 MHz,管长约620 mm.通过调节加速管的入口功率、电子枪的注入电压实现加速管的输出能量两挡调变.  相似文献   
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视频序列分割是实现视频对象提取、处理和识别的基础,也是基于内容的视频压缩和检索的前提。目前普遍采用的watershed算法是全局涨水算法,用于视频分割时占用的存储和处理空间巨大。针对这一问题本文提出了新的滑动窗口式三维watershed算法(SW3DW),通过时间轴上的局部窗口对视频序列进行观察和分割,而在相邻窗口间采用水源区标号传递和局部流域更新相结合的方法,以较小的存储和处理空间实现了局域和全局处理的一致性。理论分析和实验证明该算法能有效性地实现视频序列的分割,为后续视频对象提取和处理创造了条件。  相似文献   
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Dolomitisation is an important factor controlling reservoir quality in the Asmari Formation in many producing fields in SW Iran. Dolostones have higher average porosities than limestones. Petrographic and geochemical studies have been used to determine the causes of Asmari dolomitisation at the Bibi Hakimeh and Marun fields and at the Khaviz anticline. The formation is generally characterized by a large‐scale trend of upward‐decreasing accommodation. Basal strata were deposited under relatively open‐marine, high‐energy conditions, whereas the Middle to Upper Asmari succession was deposited in relatively protected settings with more frequent evidence of exposure and evaporitic conditions. There is a general upward increase in the abundance of both anhydrite (occurring as nodules and cement) and dolomite. Two main types of dolomite fabric are recognised, reflecting the textures of the precursor limestones: (1) finely crystalline pervasive dolomite (commonly <20μ) replacing mud‐rich facies; and (2) combinations of finely crystalline replacive dolomite and surrounding areas of coarser dolomite cement (crystals up to 100μ) in grain‐supported facies. Fluid inclusion data indicate that finely crystalline dolomites formed at low temperatures (ca. <50°C), while the coarser dolomite formed at higher temperatures (50–;140°C). Whole rock‐carbonate oxygen and carbon isotope analyses of pure dolostone samples show no apparent correlation with either depositional or diagenetic textures: δ18O is generally 0 to 2.7‰ PDB, and δ13C is ?1 to 4‰ PDB. The importance of evaporated seawater to Asmari dolomitisation is indicated by the ubiquitous occurrence of felty‐textured anhydrite nodules in dolostone beds and the presence of high‐salinity fluid inclusions in dolomite. The derivation of dolomitising fluids from contemporaneous seawater is supported by the general correspondence between age estimates derived from the strontium isotope composition of anhydrites and dolomites and those derived from stratigraphic considerations. This suggested synsedimentary dolomitisation. Dolomitisation of the upper half of the Asmari Formation may have occurred as a result of two syn‐sedimentary mechanisms: (1) by the reflux of evaporative brines concentrated in shallow lagoons or sabkhas, through immediately underlying strata (mainly during highstands); and (2) by the flushing of platform‐top carbonates by basinal evaporated waters during lowstand/early transgression. Continued dolomitisation during deeper burial is supported by the presence of high‐temperature fluid inclusions and iron‐rich crystal rims. Dolomite within the lower part of the Asmari Formation probably mostly formed during burial as a result of compaction of, and fluid exclusion from, the underlying Pabdeh marls and shales.  相似文献   
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Disposal of urban, agricultural and industrial organic residues impliesan increasing problem because of all the economic and environmentalrepercussions involved. One of the most adequate ways of managing this problemis the agricultural use of these wastes as organic amendments. Three organicresidues (AC, olive mill waste water sludge compost; MWC, municipal solid wastecompost; and PS, paper mill sludge) were used in a 3-year field experimentinvolving orange production. The effect of their application on crop productionand on soil quality was investigated. Soil samples (0–20 cm depth)collected 11 months after the last soil amendment were analysed for: pH and EC,Kjeldahl-N, available-P, available-K, total organic carbon, humic substances,dehydrogenase, phosphatase, -glucosidase, urease andbenzoyl-argininamidehydrolysing protease (BAA-protease) activities. Generally, the application of the MWC and PSincreased orange yield when compared to control. Moreover, total organic carbonand humic substances significantly increased in soils treated with all theorganic amendments. Organic fertilisation increased the Kjeldahl-N andavailable-P contents of the soil. The application of the organic residues also causedsignificant increases in dehydrogenase, -glucosidase, urease andBAA-protease activities of the soil. Significant positive correlations (p <0.01) between these enzymatic activities and total organic carbon were foundforall treatments. Significant positive correlation between dehydrogenase, urease,-glucosidase, and BAA-protease and orange yield was also found. However,a clear inhibition of phosphatase activity was observed in soils treated withPS. The results indicate that the repeated application to the soil of moderateamounts of organic amendments has positive effects on the chemical andbiochemical properties of the soil, as well as on the orange yield.  相似文献   
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