• Journal of Korean Society for Atmospheric Environment
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• v.5 no.1
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• pp.1-10
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• 1989

The sensitivity analysis is a method to quantify to what extent the output of a model changes with the values of input parameters. This will lead to increase model accuracy through measurement validation. Three line source air quality models, HIWAY 2, PAL, and CALINE 3 were selected for this study. The input parameters analysed included wind speed, wind direction, stability, emission rate, mixing height, receptor distance, initial dispersion coefficient, surface roughness, and averaging time. It turned out that PAL model generally showed higher concentration than other two models, and that between CALINE 3 and HIWAY 2, CALINE 3 showed higher concentration than HIWAY 2 model near the line sources, but beyond a certain downwind distances HIWAY 2 model showed higher concentration. The modesl were very sensitive to wind speed especially in the range of 0 $\sim$ 1 m/s and to wind direction near the parallel wind to streets. In case of emission rate, the output concentration was directly proportional to these input parameters. And the sensitivity of the input parameters such as stability, mixing height, initial dispersion coefficient, surface roughness, and averaging time were not very significant.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.11
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• pp.1007-1013
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• 2005

In this study, a step-down piezoelectric transformer was fabricated to utilize as an adapter for charging batteries of mobile electronic appliances. The ceramic part of the transformer is $Pb[(Mn_{1/3}Sb_{2/3})_{_0.05}Zr_{0.475}Ti_{0.475}]O_3$ with mechanical quality factor of 1600, electromechanical coupling coefficient $59\%$, and piezoelectric constant $d_{33}$ 1300, which can be utilized as a piezoelectric transformer. A simply fabricated disk-typed test pattern of diameter 28 mm and thickness 2 mm was used to characterize output voltage, step-down ratio as a function of electrode area with the input remained constant, and power, efficiency as a function of input voltage, and temperature-dependent electric characteristics were evaluated. The sample APT1 showed the best properties. The highest admittance, effective electromechanical coupling coefficient and an appropriate mechanical quality factor were obtained at the sample with the input/output area ratio of 1:1.5 at the common electrode, and the condition of 20 $V_{rms}$, $50\;\Omega$ made the maximum efficiency of $95\%$. The temperature was increased by 14.7'E as the input voltage was increased for $50\;V_{rms},\;50\;\Omega$.

• Land and Housing Review
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• v.11 no.4
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• pp.15-26
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• 2020

This study analyzes the Domestic Economic Ripple Effect (DERE) of the Donghae-Bukpuseon Railway (DBR). Input-Output Analysis and Scenario Analysis are employed. First, the future demand is approximately 6.86 billion people, 1.4 billion tons of logistics, and future forecast production is 1.2 trillion won for passengers, and 0.15 trillion won for logistics. Second, the production inducement (PI) coefficient of the railway industry is 2.080, the value-added inducement (VAI) coefficient is 0.680, the import inducement (II) coefficient is 0.32 and the employment inducement (EI) coefficient is 6.45. Third, for the DERE, PI is 2.846 trillion won, VAI is 0.939 trillion won, II is 0.446 trillion won, and EI is 8,737 people/1 billion won. Fourth, PI is approximately 2.8 trillion won, and the payback period is 35 years. Scenario 1 (a 50% increase in the demand for tourism) takes approximately 27 years, Scenario 2 (an 100% increase), 20 years, and Scenario3 (an 150% increase), 16 years. The successful way of the DBR is to enlarge the linkage effect of trans-railways for which international cooperation and agreements are needed. Also, even if the DBR is isolated due to worsening inter-Korea relations, the development of tourism resources is important for public investment feasibility.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.335-338
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• 1998

This paper presents calculated results for the infinite phased arrays of the probe-fed rectagualr microstrip patches. A numerical model that is based on a rigorous Green's function and galerkin solutionsis is described. In an arbitrary scan plane, the input impedance and the input reflection coefficient versus the scand angle are calculated. The effects of substrate parameters on the phased arry antenna are considered. The scan blindness phenomenon due to the surface wave is observed and the input impedance bandwidth in the arbitrary scan plane is calculated.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1996.11a
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• pp.58-62
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• 1996

To check the variability of the effective diffusion coefficient in the unsaturated porous soil media. a Monte Carlo simulation was done for the equation suggested by Millington and Quirk(1961). The results shows that the probability density function of D$_{c}$/D$_{o}$ is positively skewed. It means the chance of having less effective diffusion coefficient values in the soil media than mean value is high. Also, the distribution types of D$_{c}$/D$_{o}$ are about same regardless of assumed distribution types of input parameters.ers.ers.

• Economic and Environmental Geology
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• v.54 no.5
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• pp.573-580
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• 2021

This study analyzed the induced effects of the aggregate and stone sectors using the industry association table. First, the added value of the aggregate and stone sectors was summarized, and then the intermediate input structure and induced effect were analyzed. In terms of value-added structure, aggregate and stone showed a higher employee remuneration rate compared to the manufacturing industry, and a higher rate of operating surplus compared to other mining industries. The intermediate input structure summarizes the sector using aggregate and stone products as intermediate inputs and their input ratio. The proportion of the intermediate element input structure was confirmed. In addition, the main input sectors of ready-mixed concrete, the largest consumer of aggregate and stone, are also summarized. The production-inducing effect of aggregate and stone showed a higher influence coefficient than the sensitivity coefficient, confirming that they had a relatively large rear chain effect. The production inducement effect was reviewed by reconstructing the industry association table, and it was found to show a relative superiority in the influence coefficient, similar to the results derived according to the provisional classification of the Bank of Korea.

• Journal of the Economic Geographical Society of Korea
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• v.21 no.2
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• pp.77-89
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• 2018

The purpose of this paper is to analyze the industrial linkage between manufacturing and service industries in Seoul and Busan. In this paper, the industrial linkage between the manufacturing and the service industry is analyzed through input-output coefficient and production inducement coefficient. The results are as follows. First, the linkage of the service industry to the manufacturing in Seoul was higher than that of Busan. Second, Busan had a low input proportion of the service industry supplied by its own area to the manufacturing, so that the effect of the growth of Busan manufacturing on the regional economy is limited. Third, the linkage of manufacturing to service industry in Busan was found to be higher than that of Seoul. Finally, policy directions for improving the industrial linkage between manufacturing and service industries were suggested based on the results.

• The Journal of Fisheries Business Administration
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• v.42 no.1
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• pp.85-96
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• 2011

We have done the input-output analysis to see the over all impact of flounder industry of Jeju region on the domestic economy of Korea. To do the input-output analysis, we have constructed the data set for the input-output table by using the existing data set in the "2003 input- output table of Jeju regional area" published by the joint work of Jeju branch of Korea bank and the Jeju Development Institute, together with some raw data provided by Jejudo Marine Fish-Culture Cooperative. We have also produced input coefficient of flounder industry by making flounder industrial sector exogenous, separated from intermediate demand. To summarize our empirical results, the inducement effect of production, value added, and employment of Jeju flounder aquaculture industry are 300 billion won, 116 billion won and 1,800 people respectively. In conclusion, the results of this study suggest flounder industry of Jeju region contributes powerfully to not only Jeju economy but also all over the Korea economy.

• Coupled systems mechanics
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• v.11 no.1
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• pp.1-14
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• 2022

The key parameter that affects the consolidation process of soil is the coefficient of permeability. The common assumption in the consolidation analysis is that the coefficient of permeability is porosity-dependent. However, various authors suggest that the strain-dependency of the coefficient of permeability should also be taken into account. In this paper, we present results of experimental and numerical analyses, with an aim to determine the strain-dependency of the coefficient of permeability. We present in detail both the experimental procedure and the finite element formulation of the two-dimensional axisymmetric numerical model of the oedometer test (standard and modified). We perform a set of experimental standard and modified oedometer tests. We use these experimental results to validate our numerical model and to define the model input parameter. Finally, by combining the experimental and numerical results, we propose the expression for the strain-dependent coefficient of permeability.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.11
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• pp.1184-1190
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• 2003

In this paper, we investigated the characteristics of compensation for distorted NRZ signal and RZ signal in 320 Gbps WDM system as a function of channel input power, fiber dispersion coefficient and transmission length, respectively. The considered WDM transmission system is based on mid-span spectral inversion(MSSI) compensation method having highly nonlinear dispersion shifted fiber(HNL-DSF) optical phase conjugator(OPC) in the mid-way of total transmission line. We confirmed that the signal input power range compensated by MSSI is broadened by using RZ as a signal format in WDM system with small fiber dispersion coefficient, The range of fiber dispersion coefficient compensating overall distorted WDM channels is limited, because degree of compensation for distorted channel with low conjugated-wave power becomes gradually degrade as fiber dispersion coefficient becomes gradually higher. It is showed that RZ format and NRZ format is suited for long-haul transmission in WDM system with small fiber dispersion coefficient and with large fiber dispersion coefficient, respectively.