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991.
1概况天瑞集团汝州水泥有限公司5000t/d新型干法水泥熟料生产线,是规划两条线中的第二条生产线,年产熟料160万吨,包括从原料进厂破碎至水泥熟料出厂的一条完整的5000t/d水泥熟料生产线。工程总投资2.85亿元,从生料均化库桩基开始到生产线一次点火投产仅用了10个月另2天。无论从 相似文献
992.
993.
Zeyun Yu Jun Wang Zhanheng Gao Ming Xu Masahiko Hoshijima 《Computer methods and programs in biomedicine》2014
In this paper we present a new software toolkit for generating and optimizing surface and volumetric meshes from three-dimensional (3D) biomedical imaging data, targeted at image-based finite element analysis of some biomedical activities in a single material domain. Our toolkit includes a series of geometric processing algorithms including surface re-meshing and quality-guaranteed tetrahedral mesh generation and optimization. All methods described have been encapsulated into a user-friendly graphical interface for easy manipulation and informative visualization of biomedical images and mesh models. Numerous examples are presented to demonstrate the effectiveness and efficiency of the described methods and toolkit. 相似文献
994.
This paper proposes a novel automatic method for the moment segmentation and peak detection analysis of heart sound (HS) pattern, with special attention to the characteristics of the envelopes of HS and considering the properties of the Hilbert transform (HT). The moment segmentation and peak location are accomplished in two steps. First, by applying the Viola integral waveform method in the time domain, the envelope (ET) of the HS signal is obtained with an emphasis on the first heart sound (S1) and the second heart sound (S2). Then, based on the characteristics of the ET and the properties of the HT of the convex and concave functions, a novel method, the short-time modified Hilbert transform (STMHT), is proposed to automatically locate the moment segmentation and peak points for the HS by the zero crossing points of the STMHT. A fast algorithm for calculating the STMHT of ET can be expressed by multiplying the ET by an equivalent window (WE). According to the range of heart beats and based on the numerical experiments and the important parameters of the STMHT, a moving window width of N = 1 s is validated for locating the moment segmentation and peak points for HS. The proposed moment segmentation and peak location procedure method is validated by sounds from Michigan HS database and sounds from clinical heart diseases, such as a ventricular septal defect (VSD), an aortic septal defect (ASD), Tetralogy of Fallot (TOF), rheumatic heart disease (RHD), and so on. As a result, for the sounds where S2 can be separated from S1, the average accuracies achieved for the peak of S1 (AP1), the peak of S2 (AP2), the moment segmentation points from S1 to S2 (AT12) and the cardiac cycle (ACC) are 98.53%, 98.31% and 98.36% and 97.37%, respectively. For the sounds where S1 cannot be separated from S2, the average accuracies achieved for the peak of S1 and S2 (AP12) and the cardiac cycle ACC are 100% and 96.69%. 相似文献
995.
Tresvyatskii S. G. Terekhovskii B. I. Kashtalyan Yu. A. Klimenko V. S. Gogotsi G. A. 《Refractories and Industrial Ceramics》1968,9(3-4):229-232
Conclusions An addition of 10–60 wt.% of boron nitride significantly alters the thermal conductivity, thermal expansion, and the elastic modulus of aluminosilicate refractories.As the boron nitride content is increased from 1–60% the strength of specimens heated in a nitrogen atmosphere with an oxygen content of 0.02% decreases.During cyclic heat treatment in an oxidizing atmosphere between 900 and 20°C additional bonds develop between the particles of the aluminosilicate and the oxygen-free additive. As a result the strength of the specimen increases.The thermal shock resistance of the specimens increases with an increase in the amount of boron nitride addition. Specimens with 40–50% boron nitride addition are in practice insensitive to temperature drops in the range 20–2400°C.Aluminosilicate refractories with the addition of 30–40 wt.% of boron nitride can be used as lining material in high temperature systems with brief nonsteady or cyclic work schedules.Translated from Ogneupory, No. 4, pp. 36–39, April, 1968. 相似文献
996.
997.
M. Yu. Ustinov S. E. Artemenko G. P. Ovchinnikova G. A. Vikhoreva A. N. Guzenko 《Fibre Chemistry》2004,36(3):189-192
The important possibility of fabricating biodegradable materials by incorporating different bio- and photodegradable additives in the polymer is demonstrated. Changes were found in the structure and properties of degradable materials during exposure to soil microorganisms, air, and UV radiation for different times. The results obtained can serve as the basis for a more in-depth investigation of the mechanism of degradation of PCM. 相似文献
998.
Safe Landing Analysis of a Quadrotor Aircraft With Two Legs 总被引:1,自引:0,他引:1
We proposed a multi-propeller multifunction aerial robot (MMAR) that is composed of a quadrotor with two legs. The legs can increase the function of the robot. We found that the legs can increase the safety region of the robot during the landing. To study the safety problem, the dynamics of MMAR interacting with environment should be solved. On the basis of the interaction dynamics, this paper investigates the velocity constraint for safe landing of MMAR. The investigation begins from the kinematics and dynamics of MMAR in flight mode. Then the impact dynamics of MMAR during landing is developed. Furthermore, the landing safety problem is formulated by a series of constraint equations which can give a safety region of the velocity during landing. The safety region can give the safe velocity of the aerial robot before landing. Finally, simulation examples are presented using the proposed methodology. In the examples, a detailed safety region of a simulated MMAR is constructed and shown. 相似文献
999.
The process of nitride formation in burning of iron-silicon melt in gaseous nitrogen was investigated. It was found that silicon
nitride is synthesized at temperatures (2100°C) which are much higher than the temperature of appearance of the liquid phase
(1206°C). Silicon is in the liquid state during synthesis in the form of an iron-silicon melt and a gaseous melt. The electron-microscopic
studies showed that silicon nitride crystals grow according to two mechanisms: vapor-liquid-crystal and crystallization from
iron-silicon melt. The ratio of the contributions of these mechanisms to structural formation of silicon nitride is determined
by the conditions of synthesis.
__________
Translated from Steklo i Keramika, No. 8, pp. 18–21, August, 2007. 相似文献
1000.
Qin Zou Yu Cao Qingquan Li Qingzhou Mao Song Wang 《Machine Vision and Applications》2014,25(7):1841-1858
Recent inpainting techniques usually require human interactions which are labor intensive and dependent on the user experiences. In this paper, we introduce an automatic inpainting technique to remove undesired fence-like structures from images. Specifically, the proposed technique works on the RGBD images which have recently become cheaper and easier to obtain using the Microsoft Kinect. The basic idea is to segment and remove the undesired fence-like structures by using both depth and color information, and then adapt an existing inpainting algorithm to fill the holes resulting from the structure removal. We found that it is difficult to achieve a satisfactory segmentation of such structures by only using the depth channel. In this paper, we use the depth information to help identify a set of foreground and background strokes, with which we apply a graph-cut algorithm on the color channels to obtain a more accurate segmentation for inpainting. We demonstrate the effectiveness of the proposed technique by experiments on a set of Kinect images. 相似文献