• Korean Journal of Environment and Ecology
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• v.25 no.1
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• pp.17-30
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• 2011

This study has analyzed the vegetation composition in the areas using different slope revetment techniques of riverbanks, in a way to improve the vegetation induction in the future considering the ecological aspects of the induction in Garaeyoul Village, Gangdong-gu, Seoul. The result of the vegetation distribution in each different slope revetment technique was analyzed, that the naturalized herb was dominant in the pole block accounting for 70.7%, while native herb was dominant in the lawn block occupying 48.5% and in the crib block occupying 55.7%. The vegetation coverage measured by different slope revetment techniques was highest in the crib block(average 97.5%), followed by the lawn block(average 95.3%) and pole block(average 27.9%). The vegetation base area was the most wide in the crib block and the most narrowest in the pole block. The result of community analysis in areas using different slope revetment techniques, dry herbs and vine herbs were dominated and the coverage was very poor in the pole block. In the lawn block, the barb was fragmented into narrow areas due to the blocks, which prevented the creation of large-scale plant communities. In the crib block, Miscanthus sacchariflorus, Fescue arundinacea and Aster pilosus, which also consisted of large-scale communities. Average dry weight was also measured by each slope revetment technique. The weight was heaviest in the crib block with $187.63g/m^2$, followed by the lawn block($137.65g/m^2$) and pole block($6.75g/m^2$). The soil moisture contents in the crib block and lawn block was 16.3% and 15.2%, respectively, while that of the pole block was 4.7%, which revealed the highly dry condition of the pole block soil. The analysis result of soil chemical property showed that there was little difference in soil texture, soile acidity(pH), and exchangeable ion content, however, the soil organic matter(OM) content and available $P_2O_5$ were highest in the pole block. In the future, in order to induce more vegetation into river banks and walls, a proper construction method should be applied so that the vegetation area can be expanded as much as possible, considering the safety of the banks.

• Journal of the Korean GEO-environmental Society
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• v.13 no.11
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• pp.5-10
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• 2012

Many electric poles in the softground have been collapsed due to external load. In this study, several tests were performed with variation of numbers and depths of anchor blocks to find effects of anchor blocks on stability of concrete electric poles through earth pressure and displacement analysis. 1.50m depth of anchor block seems appropriate among three kinds of depths. The 2.25m depth of anchor block makes larger displacement due to disturbance caused by excessive excavation. The deeper anchor block, the less earth pressure of passive zone, an active earth pressure gets larger. When two anchor blocks were installed, displacement at top pole decreased 43.8% and 55.6% at ground when 1 anchor block was installed.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.9
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• pp.49-55
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• 2010

Many electric poles in the softground have been collapsed due to external load. In this study, 10 types of tests were performed with variation of location, numbers and depths of anchor blocks as well as depth of poles to find stresses acting on concrete electric poles. The stresses of concrete poles are relaxed at 600~700[kg] of tensile load, and stresses are concentrated at top of pole, and spread to lower part of pole. In the concrete pole collapse test, tensile load at failure was approximately 1,400[kg], which is twice of design load. As passive zone in the soil increases, the stresses acting on concrete pole are concentrated at lower part of pole based on moment arm earth pressure distribution.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.5
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• pp.42-49
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• 2009

The effects of various forces acting on concrete pole are analyzed using finite element method how the forces affect on ground displacement. The soil types, wind load location of anchor block embedded depth of pole, and distance between poles are varied to find out effects on lateral displacement. Anchor block is effective when it is located at 1/4 of embedded depth The displacement is decreases as elastic modulus increases. Concrete reinforcement for loosened ground is necessary for double poles because double poles cause large excavation. When embedded depth ratio decrease, lateral displacement increase as closer to ground surface. Large embedded depth is effective to reduce lateral displacement, and the distance between poles is not much large factor.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.20-27
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• 2020

In general, a nonlinear system is linearized in the form of a multiplication of the 1st and 2nd order system. This paper reports a design method of a weighting matrix and control law of LQ control to move the double poles that have a Jordan block to a pair of complex conjugate poles. This method has the advantages of pole placement and the guarantee of stability, but this method cannot position the poles correctly, and the matrix is chosen using a trial and error method. Therefore, a relation function (𝜌, 𝜃) between the poles and the matrix was derived under the condition that the poles are the roots of the characteristic equation of the Hamiltonian system. In addition, the Pole's Moving-range was obtained under the condition that the state weighting matrix becomes a positive semi-definite matrix. This paper presents examples of how the matrix and control law is calculated.

• The Journal of the Acoustical Society of Korea
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• v.28 no.1
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• pp.51-60
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• 2009

This paper presents a new method of designing room equalization filters using a warped common acoustical pole and zero (WCAPZ) modeling. The proposed method is capable of significantly reducing the order of the equalization filters without sacrificing the filter performance, especially, at low frequencies. Thus, the associated input-output delay is much smaller than the conventional block transform method while its computational complexity is comparable to it. The computational complexity also is still comparable to the conventional room equalization method, since the filter is implemented in the linear frequency domain after the pole-zero dewarping. Simulation results confirm that the use of the proposed algorithm significantly improves the room equalization over a range of low frequencies.

• The Korean Journal of Zoology
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• v.39 no.2
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• pp.173-181
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• 1996

The time-course process by which spermatozoa penetrates through the micropvle apparatus into the egg cytoplasm of rainbow trout, Oncorhvnchus mvkiss, was examined with transmission and scanning electron microscopy. In the unfertilized egg, the ess surface beneath the inner opening of the micropylar canal did not differ distinctly from the rest of the animal pole area. A spermatozoon attached to the micropvle opening 20 seconds after insemination. In the initial stases of penetration, the spermatozoon still within the micropvlar canal attached perpendicularly at its apical tip to the ess surface, then the sperm head was rapidly engulfed by the folded egg surface with its manly microvilli. A large fertilization cone with microvillus-free surface appeared on the esS surface sutra-rounding the penetrating spermatozoon. The head portion of the penetrating spermatozoon was completely wrapped by the ess surface with only the tail portion visible externally 30 seconds after insemination. The fertilization cone displayed the tail portion of the penetrating spermatozoon on the central portion of its surface 60 seconds after insemination. 150 seconds after insemination, breakdown of the cortical granules elevation were initiated at the animal pole, then completed at the vegetable pole area. The spermatozoon disappeared from the outer surface of the ess before the fertilization cone completely retracted 250 seconds after insemination. In result, the block to polvspermv to permit entry of a sin81e sperm is considered to be mechanical by the rnorpholoSical design of the micropvle and fertilization cone.

• 제어로봇시스템학회:학술대회논문집
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• 1986.10a
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• pp.90-94
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• 1986

This paper describes expansion of the state space pole assignment self-tuning control of SISO systems with system noise and abservation noise to that of MIMO systems. Resursive Prediction Error method is used for both parameter and state estimation in the block controllable canonical form. This simplifies the state feedback law by eliminating the online computation of transformation matrix.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.6
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• pp.863-869
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• 2013

In this paper, we compared and analyzed for safety 1.2m rectangular anchor block and arch-type root anchor block. First, numerical analysis was performed three-dimensional nonlinear method by numerical model test using finite element analysis program "Visual FEA". Then, measure displacement of the surface of the earth after construct each anchor block at 14M electric pole and increase loads through field verification tests for safety evaluation.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.8
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• pp.62-69
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• 2010

Many electric poles in the softground have been collapsed due to external load. In this study, 10 types of tests were performed with variation of location, numbers and depths of anchor blocks as well as depth of poles to find horizontal earth pressure through full scale pull-out tests. The horizontal earth pressure increased with embedded depth of electric pole, and earth pressure of lower passive zone decreased. The deeper of anchor block, earth pressure of passive zone becomes less. 4 anchor blocks decreased earth pressure at G.L.-0.9[m]. It is considered that 4 anchor blocks installed along 80[cm] vertically are main reason. Overall, when more anchor blocks are constructed, excavation area is large, and constructivity such as backfill is bad, therefore one anchor block would be preferred.