排序方式： 共有12条查询结果，搜索用时 0 毫秒
1.
爆炸危险区建筑物空调设计选用方案有:正压室内安设普通空调;应用防爆空调机和防爆增压机组;单独应用防爆空调机;采用半防爆半隔离系统等。 相似文献
2.
Abdel-Azim A. Abdel-Azim 《Polymer Bulletin》1993,30(5):579-586
At 298 K, intrinsic viscosity [], has been measured for fifteen polystyrene, PS, samples of different relative molar masses M in pure toluene T, and seven different binary solvents. These solvents were toluene / methanol (MeOH) mixtures having different volume fractions of MeOH. The -composition for the binary solvent system was found to be 77% T / 23% MeOH at 298 K. The dependance of excluded volume of polymer molecules on M and the solvation power was demonstrated. A constant value of 0.633 nm for the effective unit length, b, was obtained under -condition. Meanwhile a non-constancy of b, obtained in case of thermodynamically good solvents, was attributed to the neglect of excluded volume effect. 相似文献
3.
一种新型空调--全新风湿能空调器的研究 总被引：8，自引：0，他引：8
全新风湿能空调器具有杀菌、消毒、过滤作用，可保持室内空气清新，克服普通空调热回收效率低、使用成本高的缺点，采用微电脑控制，操作简单，维护方便。 相似文献
4.
王树忠 《哈尔滨理工大学学报》2011,16(4):118-120,125
针对带不可微项方程的求解问题,给出了一种改进的弦截法.该方法在迭代过程中不需要计算函数的导数值,而是用函数的均差来替代导数值,利用优序列技巧,在y一条件下,证明了该迭代格式的收敛性,并给出了误差估计.得到的结果为:当判据α满足一定条件时,该迭代格式所产生的向量序列{zn}与{wn}均收敛于带不可微项方程的唯一解z*. 相似文献
5.
用变频调速技术改造纺纱传统空调设备 总被引：1，自引：0，他引：1
介绍用变频调速技术改造纺织厂纺纱车间传统空调设备的经验、方法、获得的高节能率、技改中发生的问题及解决问题的途径。 相似文献
6.
The paper focuses on the numerical approximation of discrete fractional order systems with the conditions of nonzero initial instant and nonzero initial state. First, the inverse nabla Laplace transform is developed and the equivalent infinite dimensional frequency distributed model of discrete fractional order system is introduced. Then, resorting the nabla discrete Laplace transform, the rationality of the finite dimensional frequency distributed model approaching the infinite one is illuminated. Based on this, an original algorithm to estimate the parameters of the approximate model is proposed with the help of vector fitting method. Additionally, the applicable object is extended from a sum operator to a general system. Three numerical examples are performed to illustrate the applicability and flexibility of the introduced methodology. 相似文献
7.
8.
电力系统病态潮流的同伦方法求解 总被引：6，自引：0，他引：6
本文将大范围收敛的同伦方法用于求解电力系统病态潮流，提出了一种适合于潮流方成绩坐标形式的同伦方程，经过对典型病态系统的数值计算，表明对于潮流的病态问题取得了良好的效果。 相似文献
9.
In the present study, the comparison between the results obtained from the linear and quadratic approximations of the Galerkin Finite Element Method (GFEM) for neutronic reactor core calculation was reported. The sensitivity analysis of the calculated neutron multiplication factor, neutron flux and power distributions in the reactor core vs. the number of the unstructured tetrahedron elements and order of the considered shape function was performed. The cost of the performed calculation using linear and quadratic approximation was compared through the calculation of the FOM. The neutronic core calculation was performed for both rectangular and hexagonal geometries. Both the criticality and fixed source calculations were done using the developed GFEM-3D computational code. An acceptable accuracy with low computational cost is the main advantage of applying the unstructured tetrahedron elements. The generated unstructured tetrahedron elements with Gambit software were used in the GFEM-3D computational code via a developed interface. The criticality calculation was benchmarked against the valid data for IAEA-3D and VVER-1000 benchmark problems. Also, the neutron fixed source calculation was validated through the comparison with the similar computational code. The results show that the accuracy of the calculation for the both linear and quadratic approximations improves vs. the number of elements. Quadratic approximation gives acceptable results for almost all considered number of the elements, while the results obtained from the linear approximation have good accuracy for only high number of the elements. 相似文献
10.
本文引入点满足Δ2—条件及一致Δ2—条件的概念,讨论了点与函数二者满足Δ2—条件之间的关系,并且给出了点满足一致Δ2—条件的充分必要条件. 相似文献