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131.
Objective To reconstruct an augmented breast that resembles a virginal one that is difficult to be achieved by the traditional technique. Methods We modified the dissection of the subpectoral space by extending it over the sternum edge 1cm medially and beyond the breast crease 2cm inferiorly, yet keeping strictly the upper border of the space on the third rib and the lateral border on the anterior axillary line. Results All 50 patients were satisfied with their augmented breasts which nearly resembled the virginal ones. Conclusion Our modified dissection enabled the mammary implant to stay in the position where it originally was and not be pushed upward and laterally by the pectoral muscle contraction as usually seen by the traditional technique.  相似文献   
132.
This paper investigates the function of doubly-fed asynchronous machine(DASM)with emphasis placed on its ability to the stabilization of the power system including wind generators.P(active power)and Q(reactive power)compensation from DASM can be regulated independently through secondary-excitation controlling.Simulation results by power system computer aided design(PSCAD)show that DASM can restore the wind-generator system to a normal operating condition rapidly even following severe transmission-line failures.Comparison studies have also been performed between wind turbine pitch control and proposed method.  相似文献   
133.
唐僧一行参与乃至领导了盛唐时期的皇家天文台的工作,编制了著名的《大衍历》,本文从文化角度对沙门一行制历的因缘加以考证,认为促成一行制历的原因:一是政治统治的需要,二是沙门一行的俗家家世背景,三是沙门一行的宗教身份,且三者层层递进。其中一行的宗教身份,解释了其复杂知识结构以及《大衍历》域外天文学知识的可能来源,同时一行囊天台宗和律宗的修行身份并入于密教,加上文献材料中所体现出来的道教背景,契合了玄宗朝的宗教政策,是获得玄宗信赖的重要原因。而对于沙门一行制历的缘由,对于一行宗教背景中的道教成份,也是前贤的研究所忽略的。  相似文献   
134.
An improved Monte Carlo method was used to simulate the motion of electrons in c-C_4F_8 and SF_6 gas mixtures for pulsed townsend discharge. The electron swarm parameters such as effective ionization coefficient, [AKα-] and drift velocity over the E/N range from 280~700 Td(1Td=10-21 V·m2) were calculated by employing a set of cross sections available in literature. From the variation cure of [AKα-] with SF_6 partial pressure p, the limiting field (E/N)_lim of gas mixture at different gas content was determined. It is found that the limiting field of c-C_4F_8 and SF_6 gas mixture is higher than that of pure SF_6 at any SF_6 mixture ratio. Simulation results show excellent agreement with experiment data available in previous literature.  相似文献   
135.
This paper presented a new-type CNC curve grinding machine, in order to conquer the disadvantages of conventional NC curve grinding machine and improve surface quality, dimensional accuracy and machining efficiency. The new-type grinder adopts some high and new technologies: ① the normal tracing device could make grinding wheel coincide with the normal direction of the machining points in work piece, and improve surface quality and dimensional accuracy; ② the digital image on-line recognition system could monitor machining process and compensate wheel wear in real time; ③ linear motor drive mechanism could realize the exact adjustment of the grinding head digitally and increase the machining efficiency. The math models of normal tracing and circular tolerance zone were presented. The experimental results show that the new-type CNC curve grinding machine equipped with the three devices mentioned above is easy to realize the precision grinding of any complex curve, and improve surface quality, dimensional accuracy and machining efficiency.  相似文献   
136.
The eigenvector of a module with six adjacent module's state was constructed according to self-reconfigurable robot M-Cubes and the configuration of system was expressed with the eigenvectors of all modules.According to the configuration and motion characteristics of the modules,a 3-dimension motion rule set was provided.The rule sets of each module was run according to eigenvector of the module after the motion direction of system decided and motion rules were selected.At last,the rapid and effective motion and metamorphosis were realized in system.The rule sets are operated on three systems and the distributed motion of system is fully realized.The result of simulation shows that the 3-dimension motion rule sets has perfect applicability and extensibility.The motion steps and communication load of the modules increase with the module number in linear.  相似文献   
137.
浅谈建筑施工企业工程造价控制的若干方法   总被引:2,自引:0,他引:2  
对建筑施工企业而言,建设工程项目的成本直接关系到项目的成败,关系到建筑施工企业的发展,同时也是工程竞标的主要因素。阐述了建筑施工企业工程造价控制的一些做法,诸如:合理预测工程项目的成本,抓好工程实施阶段的成本控制和做好工程实施阶段实质性管理工作。由此实现施工管理效益最大化。  相似文献   
138.
沥青混凝土路面冷再生工程中旧料结团状况的评价与控制   总被引:1,自引:0,他引:1  
凌宏杰  王德信  白焕娥  吴旷怀 《公路》2008,(11):221-225
通过对广深高速公路旧路面回收料RAP结团状况的研究,提出了细度模数比FMR(fineness modulus ratio)这一量化评价指标,通过试验证实了该指标适合于RAP结团状况的评价,并提出了在沥青混凝土路面冷再生工程中运用该指标进行旧料结团状况控制的方法和建议.  相似文献   
139.
张铁军  唐琤琤  米晓艺  吴玲涛 《公路》2008,(12):122-127
针对平原区四车道无中间分隔带公路,借用事故预测模型技术研究其安全特征和规律.基于该类公路安全的定性和定量分析,确定了普通路段、村庄路段、交叉口路段的分段方案,并加强了对货车等车型构成的考虑.建模结果中,交通量、自然交通量中货车比例、第一层路侧危险度、竖曲线弯曲度、横坡度、路面宽度对普通路段,交通量、折算交通量中货车比例、第一层路侧危险度对交叉口路段,交通量、加权的横坡度、路基宽度等对村庄路段的事故有显著影响.最后进行了实例分析.  相似文献   
140.
通过对大洋滩和樊村隧道衬砌渗漏水、路面渗水、衬砌裂缝等常见病害的整治工程实践,详细介绍病害分析、方案制定、整治加固的整个实施过程以及新技术、新工艺、新材料在工程中的运用效果。  相似文献   
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