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101.
102.
103.
关于做好农业和农村节水工作的几点思考 总被引:7,自引:2,他引:7
农业用水占我国用水总量的 70 % ,开展和推进农业节水 ,是建立节水型社会的关键 ,也是实现我国水资源可持续利用的内在要求。要做好农业和农村节水工作 ,应当十分重视“预测预报、水资源保障、城乡供水、水污染防治、防洪减灾、计量监测、技术推广、投融资、抗旱服务、政策法规”等十大体系的建立和建设 相似文献
104.
对步行轮式气垫车围裙-地面阻力特性进行了分析。建立了步行轮式气垫车围裙-地面阻力的精确数学模型,并进行了试验验证。探讨了几个主要因素对围裙-地面阻力的影响。 相似文献
105.
Xie Ming Guo Xiaoyu Wang Yanchun 《保鲜与加工》1993,(6):134-137
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
106.
《Journal of Cereal Science》2014,59(3):451-456
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
107.
Wang Jianping Mi Linshu Chen Gang 《保鲜与加工》1993,(6):32-37
The angular frequency and decaying constant of each copmonect for the
transient waveform in power systems were obtained by using the discrete Fourier transform; the amplitude and phase angle were calculated in the linear curve fitting method. And all of the parameters obtained above were treated in an unified optimization by using the curve fitting optimization of the least square method of general nonlinear funcrion so as to get the results of waveform analysis. Two examples are included. 相似文献
108.
Zhao Tingchao Huang Shanglian Chen Weimin 《保鲜与加工》1997,(5):104-109
The paper discuss the concept of fiberoptic smart civil structure,and analysis the principle of non destructive evaluation of civil structure with the help of embeded fiberoptic sensor in sensing the inner state and integrity of the structure.The typical experiment and development of fiberoptic sensing system in the health monitoring of dam,highway,bridge and buildings are overriewed. 相似文献
109.
Chen Siqing Chen Tinghuai Zhou Liuding 《保鲜与加工》1992,(4):21-25
The rank one updating formula and the parallel eliminating algorithm for linear recurrence systems ane combined fo form a MTMD parallel algorithm fo solve tridiagonal Toeplitz Cinear equations. This algorithm has a simple strictire and requires onlty a few storages as well as in-terprocessor communications. There is no special demand on the number of processors in the parallel system. The speedup can come dose to p12 comparing with the LU decomposition method (p is the number of processors). It is worth pointing out that it is proposed algcmthn that considels and organizes the parallel arithmetic in the first order linear ricurrence systems with constant coefficients. 相似文献
110.
Cao Changxiu Wang WanLiang 《保鲜与加工》1989,(5):68-75
The predictive intelligent control scheme is proposed, which is based on approximation theory and numerical method of Chcbyshev orthogonal polynomial. It has the practical value to the cold storge using widely electromagnetic valve and can be also applied similar systems in orther area. 相似文献