Development of the ANN for the Estimation of Earth Parameter and Equivalent Resistivity

Ji Pyeong-Shik,Lee Jong-Pil,Shin Kwan-Woo,Lim Jae-Yoon,Kim Sung-Soo The Korean Institute of Electrical Engineers 2005 KIEE International Transactions on Power Engineeri Vol.a5 No.4

Earth equipments are essential to protect humans and other types of equipment from abnormal conditions. Earth resistance and potential must be restricted within a low value. An estimation algorithm of earth parameters and equivalent resistivity is introduced to calculate reliable earth resistance in this research. The proposed algorithm is based on the relationship between apparent resistances and earth parameters. The proposed algorithm, which approximates the non-linear characteristics of earth by using the Artificial Neural Network (ANN), estimates the earth parameters and equivalent resistivity. The effectiveness of the proposed method is verified with case studies.

Study of seismic performance of super long-span partially earth-anchored cable-stayed bridges

Xin-Jun Zhang,Cong Yu,Jun-Jie Zhao 국제구조공학회 2019 Structural Engineering and Mechanics, An Int'l Jou Vol.72 No.1

To investigate the seismic performance of long-span partially earth-anchored cable-stayed bridge, a super long-span partially earth-anchored cable-stayed bridge scheme with main span of 1400m is taken as example, structural response of the bridge under E1 seismic action is investigated numerically by the multimode seismic response spectrum and time-history analysis, seismic behavior and also the effect of structural geometric nonlinearity on the seismic responses of super long-span partially earth-anchored cable-stayed bridges are revealed. The seismic responses are also compared to those of a fully self-anchored cable-stayed bridge with the same main span. The effects of structural parameters including the earth-anchored girder length, the girder width, the girder depth, the tower height to span ratio, the inclination of earth-anchored cables, the installation of auxiliary piers in the side spans and the connection between tower and girder on the seismic responses of partially ground-anchored cable-stayed bridges are investigated, and their reasonable values are also discussed in combination with static performance and structural stability. The results show that the horizontal seismic excitation produces significant seismic responses of the girder and tower, the seismic responses of the towers are greater than those of the girder, and thus the tower becomes the key structural member of seismic design, and more attentions should be paid to seismic design of these sections including the tower bottom, the tower and girder at the junction of tower and girder, the girder at the auxiliary piers in side spans; structural geometric nonlinearity has significant influence on the seismic responses of the bridge, and thus the nonlinear time history analysis is proposed to predict the seismic responses of super long-span partially earth-anchored cable-stayed bridges; as compared to the fully self-anchored cable-stayed bridge with the same main span, several stay cables in the side spans are changed to be earth-anchored, structural stiffness and natural frequency are both increased, the seismic responses of the towers and the longitudinal displacement of the girder are significantly reduced, structural seismic performance is improved, and therefore the partially earth-anchored cable-stayed bridge provides an ideal structural solution for super long-span cable-stayed bridges with kilometer-scale main span; under the case that the ratio of earth-anchored girder length to span is about 0.3, the wider and higher girder is employed, the tower height-to-span ratio is about 0.2, the larger inclination is set for the earth-anchored cables, 1 to 2 auxiliary piers are installed in each of the side spans and the fully floating system is employed, better overall structural performance is achieved for long-span partially earth-anchored cable-stayed bridges.

Implementation and Validation of Earth Acquisition Algorithm for Communication, Ocean and Meteorological Satellite

박상욱,이영란,이병선,황유라,이운섭 한국우주과학회 2011 Journal of Astronomy and Space Sciences Vol.28 No.4

Earth acquisition is to solve when earth can be visible from satellite after Sun acquisition during launch and early operation period or on-station satellite anomaly. In this paper, the algorithm and test result of the Communication, Ocean and Meteorological Satellite (COMS) Earth acquisition are presented in case of on-station satellite anomaly status. The algorithms for the calculation of Earth-pointing attitude control parameters including those attitude direction vector, rotation matrix, and maneuver time and duration are based on COMS configuration (Eurostar 3000 bus). The coordinate system uses the reference initial frame. The constraint calculating available time-slot to perform the earth acquisition considers eclipse, angular separation, solar local time, and infra-red earth sensor blinding conditions. The results of Electronics and Telecommunications Research Institute (ETRI) are compared with that of the Astrium software to validate the implemented ETRI software.

지반 매개변수 변화에 따른 흙막이 구조물의 불안정성 분석

김유성(You-Seong Kim),김성수(Seong-Soo Kim),김광렬(Kwang-Leyol Kim),이광준(Kwang-Joon Lee) 한국지반신소재학회 2014 한국토목섬유학회 학술발표회 Vol.2014 No.4

In this study, correlations among design parameters, for example cohesion, subgrade reaction coefficient, and load condition, that affect the analysis results of earth retaining wall were analyzed using elasto-plastic method. The results of geotechnical investigation studies field, It was found that the analysis of geotechnical investigation in the field was different from the result of design-intended analysis. There may be errors parameters calculated from the results of ground investigation in such a case. And it can be estimated that it is irrational to analysis of earth retaining wall behavior were analyzed by utilizing the parameters. As a analysis result, the cohesion of soil really has influence on the stress-strain relationship of earth retaining wall. For this reason, the definite investigation of soil parameters in the field is very important to design the earth retaining wall.

Numerical investigation on the wind stability of super long-span partially earth-anchored cable-stayed bridges

Zhang, Xin-jun,Yao, Mei Techno-Press 2015 Wind and Structures, An International Journal (WAS Vol.21 No.4

To explore the favorable structural system of cable-stayed bridges with ultra-kilometer main span, based on a fully self-anchored cable-stayed bridge with 1400 m main span, a partially earth-anchored cable-stayed bridge scheme with the same main span is designed. Numerical investigation on the dynamic characteristics, aerostatic and aerodynamic stability of both two bridge schemes is conducted, and the results are compared to those of a suspension bridge with similar main span, and considering from the aspect of wind stability, the feasibility of using partially earth-anchored cable-stayed bridge in super long-span bridges with ultra-kilometer main span is discussed. Moreover, the effects of structural design parameters including the length of earth-anchored girder, the number of auxiliary piers in side span, the height and width of girder, the tower height etc on the dynamic characteristics, aerostatic and aerodynamic stability of a partially earth-anchored cable-stayed bridge are analyzed, and their reasonable values are proposed. The results show that as compared to fully self-anchored cable-stayed bridge and suspension bridge with similar main span, the partially earth-anchored cable-stayed bridge has greater structural stiffness and better aerostatic and aerodynamic stability, and consequently becomes a favorable structural system for super long-span bridges with ultra-kilometer main span. The partially earth-anchored cable-stayed bridge can achieve greater stiffness and better wind stability under the cases of increasing the earth-anchored girder length, increasing the height and width of girder, setting several auxiliary piers in side span and increasing the tower height.

Numerical investigation on the wind stability of super long-span partially earth-anchored cable-stayed bridges

Xin-jun Zhang,Mei Yao 한국풍공학회 2015 Wind and Structures, An International Journal (WAS Vol.21 No.4

To explore the favorable structural system of cable-stayed bridges with ultra-kilometer main span, based on a fully self-anchored cable-stayed bridge with 1400 m main span, a partially earth-anchored cable-stayed bridge scheme with the same main span is designed. Numerical investigation on the dynamic characteristics, aerostatic and aerodynamic stability of both two bridge schemes is conducted, and the results are compared to those of a suspension bridge with similar main span, and considering from the aspect of wind stability, the feasibility of using partially earth-anchored cable-stayed bridge in super long-span bridges with ultra-kilometer main span is discussed. Moreover, the effects of structural design parameters including the length of earth-anchored girder, the number of auxiliary piers in side span, the height and width of girder, the tower height etc on the dynamic characteristics, aerostatic and aerodynamic stability of a partially earth-anchored cable-stayed bridge are analyzed, and their reasonable values are proposed. The results show that as compared to fully self-anchored cable-stayed bridge and suspension bridge with similar main span, the partially earth-anchored cable-stayed bridge has greater structural stiffness and better aerostatic and aerodynamic stability, and consequently becomes a favorable structural system for super long-span bridges with ultra-kilometer main span. The partially earth-anchored cable-stayed bridge can achieve greater stiffness and better wind stability under the cases of increasing the earth-anchored girder length, increasing the height and width of girder, setting several auxiliary piers in side span and increasing the tower height.

Simulation of an Earth-Air Heat Exchanger in a Commercial Greenhouse to Improve Energy Efficiency

Nauta Alex,Tasnim Syeda Humaira,Lubitz William David 한국농업기계학회 2023 바이오시스템공학 Vol.48 No.3

Purpose Greenhouses in colder northern climates typically require significant supplemental heating for year-round operation, usually provided by natural gas combustion. One potential method of reducing greenhouse energy use is to incorporate an earth-air heat exchanger (EAHE) for seasonal heat storage; however, there is little guidance in the literature on the feasibility of this technology in cold-climate greenhouses. Methods This study uses simulations to examine the potential energy savings that could be achieved in cold-climate greenhouses by incorporating an EAHE system. A lumped parameter greenhouse energy model previously developed and tested against experimental data from several commercial and passive greenhouses was modified to simulate the addition of an EAHE in a commercial-scale lettuce greenhouse. The operation and energy use of this greenhouse was simulated at several locations across Canada. Crop evapotranspiration was included in the energy balance, and the greenhouse was assumed to deploy a thermal curtain at night. Results The EAHE sub-model was validated against experimental results available in the literature and was found to accurately predict the outlet air temperature of an EAHE. The predicted change in required supplemental heating with an operating EAHE varied from a 100% reduction in Victoria, BC, to a 13.3% reduction in Winnipeg, Manitoba. Conclusions EAHE use could reduce, or in a few locations with milder winters, even remove the need for supplemental heating at commercial-scale Canadian greenhouses.

Experimental investigation on viscoplastic parameters of conditioned sands in earth pressure balance shield tunneling

Qinglin Meng,Fuzheng Qu,Shouju Li 대한기계학회 2011 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.25 No.9

A device was developed to determine the viscoplastic parameters of conditioned soil, which works on the principle of torsional shear applied to a standard vane with controlled strain rate. Rheological measurements were taken for three sand samples with the same bentonite slurry injection ratio (14.3%), but with different foam injection ratios (19%, 23%, and 27%), by changing the gasbag pressure levels (i.e., 0, 100, 200, 300, and 400 kPa) and vane speeds (i.e., 1/3.4, 1/4.1, 1/5, 1/6.4, 1/9, 1/15, and 1/30 RPM) to determine the effects of confining pressure and foam injection ratio on the viscoplastic parameters. The results show that the values of viscosity coefficient and yield stress for conditioned sands are in the range of 9.1–53.5 kPa·s and 1.5–10.2 kPa, respectively. The viscoplastic parameters increase with the increase of the confining pressure, and decrease with the increase of the foam injection ratio for all tested samples.

복소수이미지 방법을 이용한 겉보기 대지저항률 계산

김호찬,부창진,강민제 한국전기전자학회 2019 전기전자학회논문지 Vol.23 No.1

The apparent soil resistivity is used for estimating multilayer soil parameters, such as, layer’s depth and soilresistivity. The apparent soil resistivity can be measured, and also can be calculated if soil parameters are given,becacuse the apparent soil resistivity is a function of these parameters. Therefore, any optimization algorithms can beused to find these parameters which make the calculated apparent soil resistivity close to the measured one. Theequation for calculating the apparent soil resistivity is complicated and time consumed, because it is composed of aninfinite integral which includes a zero order Bessel’s function of the first kind. In this paper, a fast algorithm forcalculating the apparent soil resistivity of horizontal multilayer earth structure has been presented using complex imagemethod. 겉보기대지저항률은 층의 깊이와 대지저항률과 같은 다층 대지파라미터들을 추정하는 데 사용된다. 겉보기대지저항률은측정 될 수 있으며, 또한 겉보기대지저항률은 이들 파라미터들의 함수이기 때문에 주어진 대지 파라미터들로 계산 될 수 있다. 따라서 모든 최적화 알고리즘을 사용하여 계산된 겉보기대지저항률을 측정된 대지저항률에 가깝게 만드는 이들 파라미터들을 찾을 수 있다. 겉보기대지저항률을 계산하기위한 방정식은 0 차 Bessel함수를 포함하는 무한 적분으로 구성되어 있기때문에 복잡하고 시간 소모적이다. 본 논문에서는 수평 다층 구조의 겉보기대지저항률을 계산하기 위한 빠른 알고리즘이 복소수이미지 방법을 사용하여 제시되었다.

Effects of Antibiotics, Zinc Oxide or a Rare Earth Mineral-Yeast Product on Performance, Nutrient Digestibility and Serum Parameters in Weanling Pigs

Han, Yung-Keun,Thacker, Philip A. Asian Australasian Association of Animal Productio 2010 Animal Bioscience Vol.23 No.8

Two experiments were conducted to compare the effects of feeding a newly-developed rare earth mineral-yeast product, zinc oxide (ZnO) or antibiotics on the performance, nutrient digestibility and serum parameters of weanling pigs. In experiment 1, 150 crossbred barrows (24 d old and 6.28 kg BW) were fed one of five dietary treatments consisting of an unsupplemented basal diet or the basal diet supplemented with antibiotics (33 ppm tiamulin and 100 ppm chlortetracycline), ZnO (1,500 or 2,500 ppm) or 0.1% peptide-bound rare earth mineral-yeast. In experiment 2, 576 crossbred barrows (28 d old and 7.20 kg BW) were fed the same diets as those used in experiment 1 modified only by the addition of 1.0% Celite 545 to all diets as a digestibility marker. However, the negative control was not included. In experiment 1, weight gain was significantly lower (p<0.05) for pigs fed the negative control than for pigs fed diets supplemented with antibiotics, ZnO, or rare earth mineral-yeast. Pig performance did not differ between pigs fed the four supplemented diets. In experiment 2, there were no differences in performance between pigs fed diets supplemented with antibiotic, ZnO or rare earth mineral-yeast. The digestibility of dry matter, crude protein, calcium, phosphorus and energy were significantly (p<0.01) higher on the rare earth mineral-yeast diet than on diets supplemented with ZnO. In addition, pigs fed the diet supplemented with rare earth mineral-yeast had significantly (p<0.05) higher digestibility of histidine, lysine, threonine and valine than pigs fed the ZnO supplemented diets. Digestibility coefficients for pigs fed antibiotics tended to be intermediate to those of pigs fed rare earth mineralyeast or ZnO. In conclusion, the performance of pigs fed rare earth mineral-yeast was basically equal to that of pigs fed antibiotics or ZnO indicating that rare earth mineral-yeast can be successfully used as a growth promoter in diets fed to nursery pigs. The effects of rare earth mineral-yeast appeared to be mediated through improvements in nutrient digestibility.