4 results about "Theoretical models" patented technology

The invention provides a method for extracting a drum load spectrum of a cutting unit of a drum shearer. The method comprises the steps of obtaining a coal rock occurrence condition of a rock sample of a coal rock; testing a stress condition of a single cutting tooth of a drum of the cutting unit of the shearer to obtain a mean load model of the single cutting tooth; randomizing the mean load model of the single cutting tooth to create a cutting load random theoretical model of the single cutting tooth; according to the cutting load random theoretical model of the single cutting tooth, superposing three-way cutting force of the single cutting tooth to obtain a drum load spectrum model of the cutting unit of the drum shearer; and performing transient response analysis on each part of the drum according to the drum load spectrum model of the shearer to obtain a load spectrum of each position of each part of the drum. According to the method, random load models of the single cutting tooth are superposed to obtain random three-way force and three-way moment in the mass center of the drum, so that load input bases can be provided for subsequent calculation, analysis, optimization design and the like of a transmission system of the cutting unit of the shearer.

This method is applied to nodes of networks based on carrier sense measurements and defines as well as determines accurately the values of two quality metrics to characterize respectively the accuracy of a node in carrier sensing and the ability of said node to cope with a given workload of concurrent incoming and outgoing communication traffic. These two quality metrics characterizes the intrinsic losses of a node due to different hardware and software limitations, which generate unexpected traffic losses in the node and make experimentally obtained results not match with those obtained through theoretical models. A testing controlled scenario is provided for allowing to measure the values of the two quality metrics separately, detecting the presence of the maximum value measured for concurrent workload of the node under test in the measurement of the accuracy of said node in carrier sensing.

The invention discloses a combination which expresses a 2.5P 5.25/5 pigment and a technical method for preparing a color characterization matter by the combination. The compositions in portion by weight of the combination are: 995 to 1005 portions of CSC-B base material, 12.6 to 13.6 portions of PV23 pigment (with the content equal to 30 percent) and 2.2 to 2.3 portions of PBK7 pigment (with the content equal to 9 percent), wherein the essential component of the CSC-B base material is an acrylic acid polymer with the content of between 30 and 40 percent and the average molecular weight ranging from 150,000 to 200,000; TiO2 is selected as main white pigment with the content of between 8 and 12 percent; moreover, the contrast ratio of the base material is between 0.78 and 0.82, while the Stormer viscosity is between 90 and 100KU; and when an incident angle is equal to 85, the glossiness of the base material is between 5 and 10. The color characterization matter has ideal weathering resistance and stability and excellent proportioning reproducibility, and the raw materials and the technological process adopted by the color characterization matter accord with the requirements and the standards of environmental protection for low VOC and zero VOC; moreover, the color characterization matter has less color difference as compared with a standard value in the national standard theoretical model of the Chinese Color System as well as higher accuracy in color realization, and can be widely used in a plurality of color-related fields.