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101.
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报导采用管式结构的氯化钙-氨吸附/脱附过程传热特性试验台.试验结果表明CaCl2对NH3的吸附/脱附化学反应对CaCl2-NH3介质的传热机理有较大影响.通过建立相应物理模型对CaCl2吸附/脱附过程进行了数值分析 相似文献
103.
工业产品设计方案的模糊综合评价方法 总被引:1,自引:0,他引:1
本文根据工业产品的特点,建立了工业产品设计方案评价指标体系──-多级多指标评价体系,且具有模糊的特点.通过引入模糊优选理论,提出了设计方案模糊综合评价方法,并将其应用于除湿机的设计方案评价和选优. 相似文献
104.
Distance-related errors complicate the resolution of real-time ambiguity in medium–long baseline marine surveys. Therefore, detection and recovery of cycle slips in real time is required to ensure high accuracy of global navigation satellite system positioning and navigation in marine surveys. To resolve this, an improved method was presented, where linear combinations of the triple-differenced (TD) between carriers L1 and L2 were formed for a wide lane and free ionosphere. To overcome severe ill-conditioned problems of the normal equation, the Tikhonov regularization method was used. The construction of a regularized matrix by combining a priori information of known coordinates of reference stations, followed by the determination of the corresponding regularized parameter are suggested. A float solution was calculated for the TD ambiguity. The search cycle slip (TD integer ambiguity) was obtained using the least-squares ambiguity decorrelation adjustment (LAMBDA) method. Using our method, cycle slips of several reference station baselines with lengths of a few hundred to one thousand kilometers were detected in real time. The results were consistent with professional software, with a success rate of 100%. 相似文献
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106.
ZOUHuazhi LIHuajun LIUXiaodong LIUAixia 《中国海洋大学学报(英文版)》2005,4(2):177-184
Based on the Navier-Stokes Equations (NSE), numerical simulation with fine grids is conducted to simulate the coastal surface wave changes, including wave generation, propagation, transformation and interactions between waves and structures. This numerical model has been tested for the generation of the desired incident waves, including both regular and random waves. Some numerical results of this model are compared with available experimental data. In order to apply this model to actual cases, boundary conditions are considered in detail for different shoreline types (beach or breakwater, slope or vertical wall, etc. ). Finally, the utility of the model to a real coastal area is shown by applying it to a fishing port located in Shidao, Rongcheng, Shandong Province, P.R. China. 相似文献
107.
目的:观察柔肝通络汤联合常规西药治疗阴虚血瘀型脑梗死恢复期的临床疗效。方法:将82 例阴虚血瘀型脑梗死恢复期患者随机分为治疗组和对照组,每组各41 例。对照组予以阿司匹林肠溶片和瑞舒伐他汀钙片治疗,治疗组在对照组基础上加用柔肝通络汤治疗。比较2组治疗4周后的综合疗效,治疗前后的Barthel指数、简化Fugl-Meyer量表(FMA)评分、美国国立卫生研究院卒中量表(NIHSS)评分,脑血流动力学指标;收缩期峰流速值(Vs)、平均流速值(Vm)及搏动指数(PI)],血液流变学指标;全血高切黏度、纤维蛋白原(FIB)]及同型半胱氨酸(Hcy)水平。结果:总有效率治疗组为92.68%(38/41),对照组为75.61%(31/41),2组比较,差异有统计学意义(P<0.05)。治疗后2组NIHSS评分、PI、全血高切黏度、FIB及Hcy水平均较治疗前降低,Barthel指数、FMA评分、Vs、Vm均较治疗前升高,且治疗组改善程度均优于对照组(P<0.05)。结论:柔肝通络汤联合西药治疗阴虚血瘀型脑梗死恢复期疗效显著,能改善患者的生活质量、脑血流动力学及血液流变学指标,降低Hcy水平,值得临床推广运用。 相似文献
108.
Zhengguo Li Jieyang Tan Pengqin Tang Hao Chen Li Zhang Han Liu Wenbin Wu Huajun Tang Peng Yang Zhenhuan Liu 《地理学报(英文版)》2016,26(1):3-14
Based on county-level crop statistics and other ancillary information, spatial distribution of maize in the major maize-growing areas (latitudes 39°–48°N) was modelled for the period 1980–2010 by using a cross-entropy-based spatial allocation model. Maize extended as far north as the northern part of the Lesser Khingan Mountains during the period, and the area sown to maize increased by about 5 million ha. More than half of the increase occurred before 2000, and more than 80% of it in the climate transitional zone, where the annual accumulated temperature (AAT) was 2800–3400 °C·d. Regions with AAT of 3800–4000 °C·d became more important, accounting for more than 25% of the increase after 2000. The expansion of maize was thus closely related to warming, although some variation in the distribution was noticed across zones in relation to the warming, indicating that maize in northeast China may have adapted successfully to the warming by adjusting its spatial distribution to match the changed climate. 相似文献
109.
Qiang Fu Huajun Li Hongqing Wang Shuqing Wang Dejiang Li Qun Li Hui Fang 《中国海洋大学学报(英文版)》2018,17(3):527-534
Arc-soft-toe bracket (ASTB), as a joint structure in the marine structure, is the hot spot with significant stress concentration, therefore, fatigue behavior of ASTBs is an important point of concern in their design. Since macroscopic geometric factors obviously influence the stress flaws in joints, the shapes and sizes of ASTBs should represent the stress distribution around cracks in the hot spots. In this paper, we introduce a geometric magnification factor for reflecting the macroscopic geometric effects of ASTB crack features and construct a 3D finite element model to simulate the distribution of stress intensity factor (SIF) at the crack endings. Sensitivity analyses with respect to the geometric ratio H t /L b , R/L b , L t /L b are performed, and the relations between the geometric factor and these parameters are presented. A set of parametric equations with respect to the geometric magnification factor is obtained using a curve fitting technique. A nonlinear relationship exists between the SIF and the ratio of ASTB arm to toe length. When the ratio of ASTB arm to toe length reaches a marginal value, the SIF of crack at the ASTB toe is not influenced by ASTB geometric parameters. In addition, the arc shape of the ASTB slope edge can transform the stress flowing path, which significantly affects the SIF at the ASTB toe. A proper method to reduce stress concentration is setting a slope edge arc size equal to the ASTB arm length. 相似文献
110.