首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到10条相似文献,搜索用时 15 毫秒
1.
曾晓东 《中国电梯》2007,18(21):52-60
The author discussed the calculation of traction force for lift system consist of complex pulley and steel reeving. By two quite other derivation methods it is proved that the formula delivered in M.3, Annex M, EN81-1:1998 is full of prunes, not only the masses of suspension rope and the moments of inertia of suspension pulley, but also the moments of inertia of pulley for tension device, the convert dynamic force are out in their reckoning completely. Further more, the author pointed out some nonstandard formats for mathematical expression, and ultimately gave out a universal formula, it can be applied for any reeving rate.  相似文献   

2.
Through the analysis on the main problems existing in the urban development of Jiangsu Province, this paper points out the limitations of traditional urban system planning. It also introduces the exploration and innovation in the compilation of the Urban System Plan of Jiangsu Province, and puts forward the specific countermeasures.  相似文献   

3.
With the perception of concept of land value and the improving standards of city management,the traditionalthinking and concept of planning requires innovation.This article presents the investigation planners carried out in the reform of planning concept based on the experi-ences of other countries and with special reference to the situation in China.It is hoped that this would provide op-portunities for further discussions among planners in the country.  相似文献   

4.
On the 22nd of Aug.Premier Li Pengmet with mayors attending the inaugurationmeeting of the Association of Mayors ofChina in Zhong Nan Hai and had talks withthem when he spoke on directives and poli-cies of urban development and urban man-agement and such important issues.Li Peng pointed out that the inaugura-tion of the Association of Mayors of Chinawas a significant event in the annals of ur-ban development in China. On behalf of the  相似文献   

5.
Today, the GNSS (global navigation satellite system) is used for more complicate and accurate applications such as monitoring or stake out works. The truth lies in the fact that in the most of the times not enough attention is paid to the antenna's setup. Usually, gross errors are found in the antenna's centering, leveling and in the measurement of its height, which are significant. In this paper, a thoroughly analysis of the above mentioned errors is carried out. The influence of these errors in the calculation of the X, Y, Z Cartesian geocentric coordinates and the ~, 2, h ellipsoid geodetic coordinates of a point P on the earth's surface, is analyzed and is presented in several diagrams. Also a new convenient method for the accurate measurement of the antenna's height is presented and it is strongly proposed. The conclusions outline the magnitude of these errors and prove the significance of the antenna's proper setup at the accurate GNSS applications.  相似文献   

6.
The increase on the competitiveness, the search on the customer satisfaction, the search by reducing waste in the civil construction were facts which helped entrepreneurs and companies to seek new ways of working, being lean construction one of the ways to get that. Studies report that the application of the lean tools in construction was carried out in an isolated way. This type of application was pointed as a major factor limiting the extent of achievement in implementing lean principles. The aim of this studies is to identify opportunities to implement the principles of lean production in the service department of a construction company in Goi~is, proposing routines that try to implement the continuous improvement of its processes, eliminating waste, reducing the lead time, allow it to perform the mapping processes, applying the just-in-time and among others, providing services that add value to the customer satisfaction. It was possible to establish the average time for each step, allowing to identify possible improvements in the department, from the perspective of lean principles. The research paper concludes by pointing out the activities for the Department of Post Construction work from building companies, from lean concepts.  相似文献   

7.
These reflections on Aldo Rossi are written in New York, in a room whose window looks out to a cityscape much like one of Rossi's paintings. On the other side of the glass is a place'of vitality, humor and mystery—a place near to the spirit of Rossi's work. Close up, the texture of an old, working city is in minute focus, full of juxtapositions and accidental perspectives. Bold shapes stand out in the middle distance. Oddly powerful forms, they are full of meaning but never clearly decipherable: church towers; skyscrapers crowned with spires and pyramids; illuminated clocks; coneshaped rooftop water tanks; domes, pediments and smokestacks. Beyond are the steel webs of suspension bridges and, dimly seen through cloud and mist, the navigation lights in the harbor. These figures happen to occur in the view from one New York window. In universalized and abstracted form, they are also constant presences within the mind of AIdo Rossi.  相似文献   

8.
Through collecting,reflecting and summarizing various opinions on the conservation of the old city in South Nanjing,this paper examines the problems that the declining historic quarters are facing amid the urban renewal process.Moreover,in combination with the existing planning practices in the old city in South Nanjing,this paper carries out a discussion on the renewal of the declining historic quarters from the perspective of values,exploration and assessment of historic resources,choice of renewal methods,and support of implementation system.  相似文献   

9.
This paper aims at figuring out some of the misperceptions of Chinese people about North American culture and giving a detailed analysis of the reasons of those misperceptions from cultural perspective. At the same time, recommendations for reducing the misperceptions in understanding different cultures are provided in the paper. Some related cultural models will be applied to analyze the deep reasons of the misperceptions.  相似文献   

10.
This paper summarizes the analytical and experimental dynamic analyses carried out to assess the actual dynamic behaviour of a curved cable-stayed bridge,recently erected in the commercial harbour of Porto Marghera ( Venice,Italy). Ambient vibration tests were carried out to determine the dynamic characteristics of the bridge and more than 20 modes were identified in the frequency range 0~10Hz. In the theoretical study,a 3D FE model of the bridge was developed using an integrated CAD-FEA approach; subsequen...  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号