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981.
A minimum ring-band mathematical definition :In the done ring-band, there are at least two inner points and two outer points which scatter staggeringly on the circumference. With this definition as the rule of searching calculation' s ending,a fast numerical algorithm of gaining the minimum ring-band of a closed curve was suggested:Make a ring-band with the four points scattered staggeringly,then replace the old points with new ones continuously until all the points are located within the ring-band. The method was used in an application example to measure the spindle rotating precision of machine tools.  相似文献   
982.
Brans of 23 traditional and 12 improved (both red and white) rice varieties in Sri Lanka were screened for anti-amylase and anti-glycation activities in vitro. Varieties which showed the highest inhibitory activities at screening were further investigated for anti-glucosidase and glycation reversing as anti-diabetic properties. The same varieties were studied for selected antioxidant properties. Significantly high anti-amylase and anti-glycation activities were observed for bran extracts of red varieties compared to white varieties at screening. Traditional red rice varieties, Masuran, Sudu Heeneti, Dik Wee and Goda Heeneti, exhibited significant and dose dependent anti-amylase, anti-glycation and glycation reversing activities. These varieties also showed marked antioxidant properties. It is concluded that brans of Sri Lankan traditional red rice varieties Masuran, Sudu Heeneti, Dik Wee and Goda Heeneti may be potential food supplements for diabetes.  相似文献   
983.
The population proportion index is usually introduced to measure the level of urbanization, which is an important index to the national economy. The fast development of urbanization would inevitably cause the increase of the investment in real estate industry. Introducing the Granger Test of Causality analytical method, in this paper the relationship between the level of urbanization and the investment in real estate industry from 1986 to 2003 in China is analyzed. It reveals that both of them are on the stage of constant up - rising, and the correlation index of 0. 205 shows that the relationship between them is a mutual promoting causality.  相似文献   
984.
(1甘肃农业大学经济管理学院,兰州 730070;2兰州资源环境职业技术学院,兰州 730020)  相似文献   
985.
This paper studies the tactics choice and its improvement in the development of economy by means of Markovian Decision Programming. An optimal decision and the maximum expected revenue can be obtained. The . paper also presents the procedures and formulas of numerical evaluation.  相似文献   
986.
Investment on construction projects has become an important factor in improving the development of economy in China.The non-price bottom bidding is a representation that the investment on projects is becoming standardized.During the years of trying out the non-price bottom bidding,the colluding in bidding or bidding below the cost has happened several times,which have damaged the benefits of owners.To solve theses problems,this paper firstly studies the reason of these problems-the failure in the normal relationship between principal and agent.Then,some measures have been presented as follows: building systematic and scientific system of qualification prejudication,judging behaviors of colluding in bidding and bidding below the cost with reason and providing a surety mechanism of the project.The authors hope that these measures are beneficial to non-price bottom bidding.  相似文献   
987.
With the study of minbus's accelerated exterior noise control,the principle of sound intensity measurement was applied,the sound intensity of a minbus's surface noise was tested,and the surface noise distribution was presented.Several identification of noise source methods including sound power,sound intensity contour map,frequency spectrum were used together for surface noise analysis and study.Engine radiation noise and exhaust noise was identified as the major noise sources.On the contrary,car body vibration noise,tyre noise,transmission agent noise,air admission noise just occupied a little proportion of surface sound radiation energy.The research provides the reliable basis to determine main projects of minibus's accelerated exterior noise control.  相似文献   
988.
With the goal of the sintering of magnetite concentrates without carbon,the effect of quality,inert atmosphere and Fe_3O_4 addition on microwave sintering of magnetite concentrates is studied.It is shown that: With the same basicity(CaO/SiO_2=2.5) and microwave heating condition(1000W,2.45GHz,20min),the centre temperature decreaseds with a increasing sample mass;There is no great difference between with and without inert atmosphere in microwave sintering of magnetite in a same microwave heating condition.When 100g sample(CaO/SiO_2=2.5) is heated by microwave irradiation(1000W,2.45GHz,20min),the more Fe_3O_4 is added,the less liquid phase is produced,which is bad for microwave sintering of magnetite concentrate.  相似文献   
989.
Wavelets have been widely applied in such research areas as image processing, computer vision, network management and data mining. Wavelets have many favorable properties, which are hierarchical and multiresolution decomposition structure, linear time and space complexity of the transformations. The paper presents wavelet application on the algorithms of data mining, in cluding as clustering, classification, distributed data mining, similarity search, approximate query processing, visualization and so on. Finally, the paper concludes by discussing the impact of wavelets on data mining research and outlining potential future research directions and applications.  相似文献   
990.
In the civil industry, quality is a key factor, so quality management and quality control play decisive roles in construction especially. At present, the main method of construction is quality controlling that engineers and technicians consult the standard and norm concerned, then check them one by one, and supervise the construction. It is not only inefficient but also easy to make mistake. Using computer technology in the quality control of construction will promote quality control level and improve management measures. Through the research of the quality control of construction,the system of quality control in construction is studied and developed, the structure of the software and its developed technology are expounded.  相似文献   
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