Stress transmission coefficient: A soil stress transmission property for a loading process

The main content dealt with in this paper was to make a theoretical analysis of the vibration transmission property of spacer fabric as cushion materials. A forced vibration test with sinusoidal excitation was conducted, and the corresponding model of the vibration transmission coefficient was established based on a single-degree-of-freedom system. Experimental and theoretical vibration indexes, including natural frequency and the vibration transmission coefficient, were obtained from experimental and theoretical vibration transmission coefficient–frequency curves, respectively. After comparing theoretical parameters with experimental parameters, we were pleased to find out that their maximum vibration transmission coefficient and natural frequency showed good accordance with each other. Moreover, the effect of different parameters of spacer fabric on vibration transmission properties, including thickness, filament diameter, area density and inclination angle and arrangement of spacer filaments, were investigated, which is helpful to better design spacer fabrics with good vibration transmission.

Download Full-text

Effect of log loading on the performance of wood room

Nordic Pulp & Paper Research Journal ◽

10.3183/npprj-2014-29-02-p201-210 ◽

2014 ◽

Vol 29 (2) ◽

pp. 201-210

Author(s):

Ari Isokangas ◽

Kari Ala-Kaila ◽

Markku Ohenoja ◽

Aki Sorsa ◽

Kauko Leiviskä

Keyword(s):

Product Quality ◽

Material Properties ◽

Raw Material ◽

Performance Criteria ◽

Processing Unit ◽

Level Control ◽

Paper Mills ◽

Remarkable Effect ◽

Loading Process ◽

Small Wood

Abstract The purpose of this paper is to analyse the log loading process of wood room, which is typically the first processing unit in pulp and paper mills. The aim is to improve the log loading process to obtain production with a constant log flow of well de-iced logs to the debarking drum. This way it is possible to reduce costs and enhance product quality. The research was carried out utilising a log loading simulator. The parameters of the simulation model were selected on the basis of process observations on a mill. The results indicate that it is essential to adjust the process and equipment parameters, raw material properties and truck loader operation together in order to reach the target capacity with minimum costs. Especially the speed of the infeed conveyor affects all performance criteria and should be selected carefully. In addition, wood yard logistics and raw material properties have a remarkable effect on the wood room performance. The results can be utilised in mills to allow the upper level control perform in a planned way so that small wood loss and good product quality can be obtained.

Download Full-text

Finite Element Analysis for Cohesive Soil, Stress and Consolidation Problems Using Bounding Surface Plasticity Theory.

10.21236/ada137638 ◽

1983 ◽

Cited By ~ 3

Author(s):

L. R. Herrmann ◽

K. D. Mish

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Cohesive Soil ◽

Plasticity Theory ◽

Bounding Surface ◽

Element Analysis ◽

Bounding Surface Plasticity ◽

Surface Plasticity ◽

Soil Stress

Download Full-text

Inspecting system of heat transmission coefficient of building envelop based on Zigbee technology

IET Conference on Wireless, Mobile and Sensor Networks 2007 (CCWMSN07) ◽

10.1049/cp:20070090 ◽

2007 ◽

Author(s):

Haifeng Li ◽

Yan Zhang ◽

Lei Chen ◽

Jianhang Yang

Keyword(s):

Transmission Coefficient ◽

Heat Transmission ◽

Zigbee Technology ◽

Building Envelop

Download Full-text

Numerical simulation on coal loading process of shearer drum based on discrete element method

Energy Exploration & Exploitation ◽

10.1177/01445987211013536 ◽

2021 ◽

pp. 014459872110135

Author(s):

Zhen Tian ◽

Shuangxi Jing ◽

Lijuan Zhao ◽

Wei Liu ◽

Shan Gao

Keyword(s):

Numerical Simulation ◽

Discrete Element Method ◽

Loading Rate ◽

Low Cost ◽

Element Model ◽

Discrete Element ◽

Helix Angle ◽

Loading Process ◽

Coal Particles ◽

Element Method

The drum is the working mechanism of the coal shearer, and the coal loading performance of the drum is very important for the efficient and safe production of coal mine. In order to study the coal loading performance of the shearer drum, a discrete element model of coupling the drum and coal wall was established by combining the results of the coal property determination and the discrete element method. The movement of coal particles and the mass distribution in different areas were obtained, and the coal particle velocity and coal loading rate were analyzed under the conditions of different helix angles, rotation speeds, traction speeds and cutting depths. The results show that with the increase of helix angle, the coal loading first increases and then decreases; with the increase of cutting depth and traction speed, the coal loading rate decreases; the increase of rotation speed can improve the coal loading performance of drum to a certain extent. The research results show that the discrete element numerical simulation can accurately reflect the coal loading process of the shearer drum, which provides a more convenient, fast and low-cost method for the structural design of shearer drum and the improvement of coal loading performance.

Download Full-text

Representative Transmission Coefficient for Evaluating the Wave Attenuation Performance of 3D Floating Breakwaters in Regular and Irregular Waves

Journal of Marine Science and Engineering ◽

10.3390/jmse9040388 ◽

2021 ◽

Vol 9 (4) ◽

pp. 388

Author(s):

Huu Phu Nguyen ◽

Jeong Cheol Park ◽

Mengmeng Han ◽

Chien Ming Wang ◽

Nagi Abdussamie ◽

...

Keyword(s):

Transmission Coefficient ◽

Wave Height ◽

Wave Attenuation ◽

Transmitted Wave ◽

Irregular Waves ◽

Hydrodynamic Analysis ◽

Evaluation Approach ◽

Floating Breakwater ◽

Floating Breakwaters ◽

Evaluation Approaches

Wave attenuation performance is the prime consideration when designing any floating breakwater. For a 2D hydrodynamic analysis of a floating breakwater, the wave attenuation performance is evaluated by the transmission coefficient, which is defined as the ratio between the transmitted wave height and the incident wave height. For a 3D breakwater, some researchers still adopted this evaluation approach with the transmitted wave height taken at a surface point, while others used the mean transmission coefficient within a surface area. This paper aims to first examine the rationality of these two evaluation approaches via verified numerical simulations of 3D heave-only floating breakwaters in regular and irregular waves. A new index—a representative transmission coefficient—is then presented for one to easily compare the wave attenuation performances of different 3D floating breakwater designs.

Download Full-text

Estimation methods to extract complex permittivity from transmission coefficient in the terahertz band

Optical and Quantum Electronics ◽

10.1007/s11082-021-03087-4 ◽

2021 ◽

Vol 53 (8) ◽

Author(s):

Chuang Yang ◽

Jian Wang ◽

Cheng Yang

Keyword(s):

Transmission Coefficient ◽

Iterative Algorithm ◽

Complex Permittivity ◽

Free Space ◽

Estimation Methods ◽

Extraction Technique ◽

Initial Value ◽

Terahertz Band ◽

Terahertz Frequencies

AbstractIn this paper, the characteristics of the transmission coefficient (S$$_{21}$$ 21 ) measured in free-space at terahertz frequencies are analyzed. The analysis results are used to estimate the permittivity of the material under test, and the estimated permittivity is adopted as an initial-value for the iterative algorithm to extract the complex permittivity of the material from the S$$_{21}$$ 21 . The iterative extraction technique based on the estimation is efficient, while the iterative extraction technique without the estimation is inefficient. Various known materials in the literature are used to validate the technique in the terahertz band.

Download Full-text