• Tribology and Lubricants
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• v.38 no.3
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• pp.84-92
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• 2022

In Part I, developed was a method to obtain the stress field due to an edge dislocation that locates in an elastic half plane beneath the contact edge of an elastically similar square wedge. Essential result was the corrective functions which incorporate a traction free condition of the free surfaces. In the sequel to Part I, features of the corrective functions, F_kij,(k = x, y;i,j = x,y) are investigated in this Part II at first. It is found that F_xxx(ŷ) = F_xyx(ŷ) where ŷ = y/η and η being the location of an edge dislocation on the y axis. When compared with the corrective functions derived for the case of an edge dislocation at x = ξ, analogy is found when the indices of y and x are exchanged with each other as can be readily expected. The corrective functions are curve fitted by using the scatter data generated using a numerical technique. The algebraic form for the curve fitting is designed as F_kij(ŷ) = $\frac{1}{\hat{y}^{1-{\lambda}}I+yp}$$\sum_{q=0}^{m}{\left}$$\left[A_q\left(\frac{\hat{y}}{1+\hat{y}} \right)^q \right]$ where λ_I=0.5445, the eigenvalue of the adhesive complete contact problem introduced in Part I. To investigate the exponent of F_kij, i.e.(1 - λ_I) and p, Log|F_kij|(ŷ)-Log|(ŷ)| is plotted and investigated. All the coefficients and powers in the algebraic form of the corrective functions are obtained using Mathematica. Method of analyzing a surface perpendicular crack emanated from the complete contact edge is explained as an application of the curve-fitted corrective functions.

• Journal of the Korean Vacuum Society
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• v.12 no.S1
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• pp.116-119
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• 2003

$Ni_2$MnGa films, deposited on mica and glass substrates, were studied by ferromagnetic resonance (FMR) technology. The temperature-dependent resonance field was measured and a martensitic phase transformation (MT) was found between 310 and 340 K, exhibiting an abnormality on the curve. The easy axis is found to be in the film plane. The line width increases as a whole with decreasing temperature, which is discussed in terms of the motional narrowing mechanism. The resonance field was also measured as a function of orientation and the results were fitted, exhibiting a good consistence.

• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.753-756
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• 1992

The piezoelectric ceramics of PMS-PZT was made in the radial mode disk. As the results, in the application of filter required conditions: that is, higher-values for piezoelectric properties($K_p$, $Q_m$) and lower-values for stabilities of $F_{\tau}$(temp. coefficient, aging rate), 5PMS-51PT-44PZ composition statified well. This composition was made in the dot-ring type. Asthe results, with increasing $n^2$ both $Q_m$ and S had high values, decreasing $n^2$ both $K_p$ and BW had low values when the diameter of sintered bodies were constant. Therefore, curve of filter characteristic have sharped with increasing $n^2$ and BW broadened with decreasing $n^2$.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.297-303
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• 2007

Derailment is likely to have a direct connection with human life and must be eliminated. A traveling safety evaluation method based mainly on derailment coefficient has already established. But this method is very difficult because Derailment is caused by multiple factors. To evaluate the derailment factor of running train that runs on the curved track, we make use of mechanism that wheel loads and lateral forces were affected by track and rolling stock parameter. In this paper, deal with a search on the parameter and derailment factor. According to results of computer simulation value of Q/P, running safety is connected with operation velocity, curve radius, cant, track irregularity, suspension stiffness and static wheel load ratio, SMRT train Line No. 5 Bogie is selected to do numerical study considering rolling stock and track condition.

• Korean Journal of Environment and Ecology
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• v.32 no.5
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• pp.513-531
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• 2018

This study compared forest vegetation in Chungcheongnam-do Provincial Park (Deogsan, Chilgabsan, and Daedunsan) from 2006 to 2016. The results of the analysis on the vegetation of the research sites by the phytosociological method showed that the Deogsan Provincial Park had Quercus mongolica community, Pinus densiflora community, Q. variabilis community, and Zelkova serrata community. Chilgabsan Provincial Park had Q. variabilis community, Q. mongolica community, P. densiflora community, and Carpinus laxiflora community. Daedunsan Provincial Park had Q. mongolica community, Q. variabilis community, Q. serrata community, C. tschonoskii community, C. laxiflora community, P. densiflora community, and Q. acutissima community. The importance value in each Provincial Parks was analyzed as follows. The importance value of Q. mongolica(72.35) was the highest in Deogsan Provincial Park, and followed by P. densiflora(70.25), Q. variabilis(53.11), Styrax japonicus(11.44), Prunus sargentii(11.17), and Fraxinus rhynchophylla(10.41). Q. variabilis(73.34) was the highest in Chilgabsan Provincial Park and followed by, P. densiflora(58.71), Q. mongolica(57.02), C. laxiflora(18.84), Q. serrata(13.48), and Prunus sargentii(13.31). The importance value of Q. mongolica(57.03) was the highest in Daedunsan Provincial Park and followed by Q. variabilis(31.98), Q. serrata(31.53), P. densiflora(16.80), C. tschonoskii(16.50), C. laxiflora(16.07), S. obassia(15.76), and Acer pseudosieboldianum(10.09). The results of DBH analysis of the major species having the high importance value showed the normal density distirbution of Q. mongolica, and Q. variabilis in Deogsan Provincial Park, so the dominance status of these species is likely to continue. Q. variabilis, Q. mongolica, and P. densiflora in Chilgabsan Provincial Park showed the normal density distribution showed the density of normal distribution, so the dominance status of these species is likely to continue. However, the dominance status of C. laxiflora, and Q. serrata is likely to be expanded in the future due to the high density of young individuals. Q. mongolica, and Q. variabilis in Daedunsan Provincial Park showed the density of reverse J-shaped curve, so the dominance status of these species is likely to continue, and C. tschonoskii, and P. densiflora had a formality distribution, suggesting continuous domination of these species over the other species for the time being. Additionally the dominance status of C. laxiflora, and Q. serrata is considered to be expanded in the future due to the high density level of young individuals.

• Journal of Korea Water Resources Association
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• v.38 no.4 s.153
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• pp.271-280
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• 2005

The goal of this study is to recommend a new type of stage-discharge rating curve ($Q=p(h-e)^{\beta}-{\gamma}$) useful for satisfying divergence, and one other seemingly irresolvable problem related to exited rating curves, while also extending this rating curve model. The problem of divergence is that during the finding of the CZF (cease-to-zero flow) parameter e and while minimizing the sum of total errors of the estimated curve, the exponential parameter ${\beta}$ become an abnormally large value. The insoluble problem is that when the value e is greater then the recorded minimum at the gauged stage, it is impossible to have a negative logarithm value (h-e). The two problems above can be satisfied by adapting the control value ${\gamma}$, which affects the reduction of ${\gamma}$ and gives us the possibility of controlling (h-e) over zero. The study results show that the effects of parameter ${\gamma}$ are very similar to that of e when conducting physical and sensitivity analyses. This system can be used towards developing a new stage-discharge rating curve for river discharge, for use in evaluating the acceptability of existing stage-discharge rating curves generated by using hydrologic analyses at all stations.

• Journal of Korean Society on Water Environment
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• v.33 no.1
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• pp.51-62
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• 2017

The purpose of this study is to evaluate on the applicability of Load Duration Curve (LDC) method using Maintenance of Variance Extension types 2 method and sampling data for efficient total maximum daily loads at the Nakbon-A unit watershed in Korea. The LDC method allows for characterizing water quality data such as BOD, TOC, T-N and T-P in this study at different flow regimes(or quarters). BOD usually exceeded the standard value (exceedance probability 50%) at low flow zone. On the other hand, TOC, T-N, T-P usually exceeded the standard value at dry and low flow zone. Seasonally all water quality variables usually exceeded the standard value at Q1(Jan-Mar) and Q2(Apr-Jun) zones. Improvement of effluent control from wastewater treatment plants are effective to improve BOD and T-P.

• Korean Journal of Environment and Ecology
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• v.31 no.3
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• pp.297-317
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• 2017

The research has been conducted in order to classify the vegetation types of natural forest in Mt. Janggunbong, Bonghwa-Gun and establish its following characteristics of stands. Vegetation data were collected by June in 2014 to August in 2016. Based on the 71 quadrates, we carried out an analysis of species-area curve, vegetation types, importance value, species diversity, coincidence method and CCA. As a result of the species-area curve, it was showed the proper investigation, vascular plants consisted a total of 227 taxa; 67 families, 152 genera, 197 species, 3 subspecies, 27 varieties. The forest vegetation was classified into 7 vegetation units, when it comes to a community group, they are classified into the Quercus mongolica community group. As for community, Q. mongolica community group is classified into the Acer pictum subsp. mono community, Pinus koraiensis community and Q. variabilis community. As for group, A. pictum subsp. mono community is classified into Lychnis cognata group and Deutzia glabrata group. The P. koraiensis community is classified into A. komarovii group and P. koraiensis typical group. The Q. variabilis community is classified into Parthenocissus tricuspidata group and Q. variabilis typical group. As for subgroup, P. tricuspidata group is classified into P. tricuspidata typical subgroup and Salix caprea subgroup. As a result of the importance value, Q. mongolica showed highest importance value in tree layer of vegetation units 1, 2, 3, 4 and 5. Betula schmidtii showed highest importance value in tree layer of vegetation unit 6. P. densiflora showed highest importance value in tree layer of vegetation unit 7. In subtree layer, shrub layer and herb layer of vegetation units 6 and 7, Q. mongolica and Q. variabilis showed high importance value. This implying that a vegetation units 6 and 7 is predicted to be composed by Q. mongolica and Q. variabilis. As for species diversity, vegetation units 1, 2 and 3 showed high species diversity(2.130~2.353). It was considered to be due to the topographical characteristics of valley. As a result of coincidence method and CCA, altitude showed high correlation than other environmental factor.

• Journal of the Korean Mathematical Society
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• v.53 no.4
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• pp.869-893
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• 2016

We construct the extension of a hyperelliptic K3 surface to a Fano 6-fold with extraordinary properties in moduli. This leads us to a family of surfaces of general type with $p_g=1$, q = 0, $K^2=2$ and hyperelliptic canonical curve, each of which is a weighted complete inter-section inside a Fano 6-fold. Finally, we use these hyperelliptic surfaces to determine an 8-parameter family of Godeaux surfaces with ${\pi}_1={\mathbb{Z}}/2$.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.830-835
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• 2011

DMT Freight is judged that economic performance is good because can increase cargoes than existing freight. However, the existing freight cars, each with a different balance to the body structure is bogie because the vibrations may occur. Thus, by minimizing vibration over the existing freight securing the safety of the driving if you will not have major problems in cargoes. In this study, multi-body dynamic analysis tool, VI-Rail using the actually Gyeongbu Railroad line and an empty, full freight condition include curve radius, track irregularity, cent. DMT freight of the derailed wagons were assessed for safety analysis. Full and empty freight conditions for parity in the Gyeongbu Railroad line(Dongdaegoo ${\leftrightarrow}$Gyungsan) derailment safety analysis, such as derailment safety coefficient and the radius wheel road decrement, echoing the curve and the orbit is affected by the irregularity was found. Full freight condition than the empty conditions showed a significant derailment safety. Overall, the limits of derailment coefficient (Q/P=0.8) and wheel road decrement limits (${\Delta}P/P=0.6$) is less safe with me confirmed that the derailment safety.