• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.8A
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• pp.739-752
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• 2002

Recently, to utilize the limited bandwidth effectively, the concept of partial response (PR) signaling has widely been adopted in both the high-speed data transmission and high-density digital recording/playback systems such as digital microwave, digital subscriber loops, hard disk drives, digital VCR's and digital versatile recordable disks and so on. This paper is concerned with adaptive equalization of partial response channels particularly for the magnetic recording channels. Specifically we study how the PR channel equalizers work for different choices of desired or reference signals used for adjusting the equalizer weights. In doing so, we consider three different configurations that are actually implemented in the commercial products mentioned above. First of all, we show how to compute the theoretical values of the optimum Wiener solutions derived by minimizing the mean-squared error (MSE) at the equalizer output. Noting that this equalizer MSE measure cannot be used to fairly compare the three configurations, we propose to use the data MSE that is computer just before the final detector for the underlying PR system. We also express the data MSE in terms of the channel impulse response values, source data power and additive noise power, thereby making it possible to compare the performance of the configurations under study. The results of extensive computer simulation indicate that our theoretical derivation is correct with high precision. Comparing the three configurations, it also turns out that one of the three configurations needs to be further improved in performance although it has an apparent advantage over the others in terms of memory size when implemented using RAM's for the decision feedback part.

• Korean Journal of Remote Sensing
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• v.35 no.6_2
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• pp.1149-1160
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• 2019

In this study, two radiometric correction methods deriving reflectance from UAV multispectral image for monitoring forest vegetation were applied and evaluated. Multispectral images were obtained from a small multispectral camera having 5 spectral bands. Reflectance were derived by applying the two methods: (1) the direct method using downwelling irradiance measurement and (2) the empirical line correction method by linking a set of field reflectance measured simultaneous with the image capture. Field reflectance were obtained using a spectroradiometer during the flight and used for building the linear equation for the empirical method and for the validation of image reflectance derived. Although both methods provided the high correlations between field reflectance and image-derived reflectance, their distributions were somewhat different. While the direct method provided rather stable and consistent distribution of reflectance all over the entire image area, the empirical method showed very unstable and inconsistent reflectance distribution. The direct method would be more appropriate for relatively wide area that requires more time to acquire image and may vary in downwelling irradiance and atmospheric conditions.

• Journal of Korea Water Resources Association
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• v.40 no.2 s.175
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• pp.159-170
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• 2007

This study evaluated the parameters of Clark unit hydrograph (UH) estimated using the rainfall-runoff measurements and evaluated their variability. This also includes the quantification of basin and meteorological factors using probability density functions, selection of storm events with mean affecting factors, and derivation of average parameters of the Clark UH from storm events selected. Summarizing the results from this procedure are as follows. (1) It is not easy to avoid much uncertainty on the decision of runoff characteristics (that is, the concentration time and storage coefficient) even with some rainfall-runoff events are available. (2) As the distribution function of concentration time is very skewed, a simple arithmetic mean may lead a biased estimate. That is, the arithmetic mean based on the normal distribution can not be representative anymore. The mode may well be the representative in this case. On the other hand, the storage coefficient shows a symmetric distribution function, so the arithmetic mean may be used use for its representative. For the basin in this study, the concentration time in this study is estimated to be about 7 hours, and the storage coefficient about 22 hours.

• Korean journal of food and cookery science
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• v.21 no.6 s.90
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• pp.800-812
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• 2005

This study selected and classified the representative foods for diversifying Korean traditional foods in the globa1 market and derived the superior factor of each food by consumer survey (n=744). The superiority of Korean traditional foods was generally recognized as being in the order of 'Nutritional value' > 'Dietary culture' > 'Material' > 'Taste.' Kimchi, Tteok/Hangwa, and grilled foods were regarded as potent Korean traditional foods for global consumers. The survey about the superior factors of representative Korean traditional foods produced the following results. The superior factor of Bibimbap, Mandu, Jangachi, Joeotgal, Namul muchim Salad, Naengchae, and Ganjang was 'Variety of material or cuisine', that of Bap, Jut Samguetang, Seolleongtang, Kimchi, Doenjang, and Sikcho was 'Nutritional value', that of Naengmyeon, Kalguksu, Bulgogi, Pyeonyuk, Jeongol, Gochujang, Tteot and Sjkhae/Sujeonggwa was Taste', and that of Hangwa, Hwachae, Gujulpan, and Sinsunro was 'Appearance'. The superior factors of representative Korean traditional foods showed the following differences by age and gender, The superior factor in Mandu was 'Taste' by the subjects aged below 30 but 'Variety' by the subjects aged above 30; that in Pyeonyuk and Jeongol was 'Variety' in 31-40 year olds and those aged above 51, while it was 'Taste' in others. The superior factor of Kimchi was 'Nutritional value' by the subjects aged below 40,'Taste'in 41-50 year. olds, and 'Variety' by the subjects aged above 50, that of Namul muchim was 'Nutritional value' by the subjects aged below 20 and 'Variety'by the subjects aged above 20, and that of Naengchae was' Taste'by the subjects aged below 20 and 'Variety' by the subjects aged above 20. The superior factor of Gochujang was 'Taste' by the subjects aged below 50 and 'Variety 'by the subjects aged above 50, that of Ganjang was 'Variety' by the subjects aged below 30 and 'Taste' by the subjects aged above 30, that of Sikcho was 'Variety' by the subjects aged below 30 and 'Nutritional value' by the sutjects aged above 30. The superior factor of Doenjang was 'Nuttritional value' in all ages. The superior factors of Hangwa and Sikhae/Sujeonggwa were 'Appearance' and 'Taste' in all ages, and that of Hwachae was 'Taste' by the subjects aged below 30 and' Appearance' by the subjects aged above 30. The perception by gender was statistically differed for traditional foods such as Bap, Bibimbap, Kalguksu, Bulgogi, Pyeonyuk Jangachi, Gochujang, Ganjang, Sikhae/Sujeonggwa, Hwachae, and Gujulpan.

• Korean Journal of Remote Sensing
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• v.23 no.6
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• pp.575-581
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• 2007

Suaeda japonica is the one of halophyte species which is widely spread in the Ganghwado tidal flat. Halophyte affects to the vertical development of wetland by enhancing the adhesion force of sediments. If demineralization of tidal flat proceeds, the colony of halophyte moves to the seaside where has relatively high salinity content. The change of halophyte zonation can be an environmental indicator to understand the landization of tidal flat. To interpret the spectral characteristics of halophyte, we measured the reflectance of suaeda japonica, reed and sediment around Donggumdo tidal flat in Ganghwado. First and second-derivation analysis was applied to these transformed spectra in order to identify which spectral ranges were distinguished with different coastal wetland vegetation and artificial structures. From the result, red reflectance peak of suaeda japonica were appeared at 600-650nm and greed reflectance peak of reed were appeared at 500-570nm. Spectra of sediments were continuously increased from 350-550nm without any absorption by chlorophyll. These reflectance were easily identified among the spectra of halophyte.

• Journal of Korean Philosophical Society
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• v.129
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• pp.141-166
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• 2014

Xìng $sh{\grave{a}}n$(性善) theory of Mencius combined xìng(性) that means physical characteristic of human together $sh{\grave{a}}n$(善) that means moral value or moral behavior. Therefore in other to verify the meaning of xìng $sh{\grave{a}}n$(性善) we need to analysis human nature in Psychology and moral norm in Ethics simultaneously. And that necessity justified Moral Psychological approach to xìng $sh{\grave{a}}n$(性善). Mencius combined a priori morality and a priori moral norm and asserted xìng $sh{\grave{a}}n$(性善). And than he presented an example for a basis or a clue of mora norm and explained grounds of moral behavior. But various theory Moral Psychology considered morality as an attachment or derivation of human nature. So another new Moral Psychology is needed to investigate Mencius Xìng $sh{\grave{a}}n$(性善) theory in a viewpoint of Moral Psychology. And than that must managed morality and moral norm as essential problems firstly. That because Mencius considered human as a moral subjectivity and seek the clue or basis morality and moral norm in human nature. And secondly that must managed moral intelligence as a emotional intelligence, because of $li{\acute{a}}ng$ $n{\acute{e}}ng$(良能) $li{\acute{a}}ng$ zhī(良知) of Mencius meaned moral intelligence which was derived from blood tied and moral emotion.

• Composites Research
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• v.34 no.5
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• pp.283-289
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• 2021

This paper derives numerically the buckling Knockdown factors using two different initial imperfection models, such as geometric and loading imperfection models, to investigate the unstiffened composite cylinder with an ellipse pre-buckling deformation pattern. Single Perturbation Load Approach (SPLA) is applied to represent the geometric initial imperfection of a thin-walled composite cylinder; while Single Boundary Perturbation Approach (SBPA) is used to represent the geometric and loading imperfections simultaneously. The buckling Knockdown factor derived using SPLA is higher than NASA's buckling design criteria by approximately 84%, and lower than buckling test result by 9%. The buckling Knockdown factor using SBPA is higher than NASA's buckling design criteria by about 75%, and 14% lower than the buckling test result. Therefore, it is shown that the buckling Knockdown factors derived in this study can provide a lightweight design compared to the previous buckling design criteria while they give reasonably a conservative design compared to the buckling test for both the initial imperfection models.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.14 no.2
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• pp.168-174
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• 2021

According to the World Agricultural Productivity Report, the current annual average growth rate of agriculture is 1.63%, which is lower than 1.73% to support the world's 10 billion people, which is growing by 2050. The demand for food, feed, and bioenergy is not growing enough to continue to meet the demand, and it is predicting a future food shortage. The purpose of this study was to create a regional irrigation control model for the purpose of reducing the production cost of crops, increasing production, and improving quality, and presenting a model that can give advice to farmers who start farming in the region. The irrigation control modeling presented in this study means to represent the change of medium weight·supply liquid·drainage amount due to changes in the root zone environment according to the passage of time and climate in a graph model. For water control modeling, we collected data on the change in the amount of the root zone environment and the weight of the badge·supply amount·drainage amount from March to June in Nonsan, Buyeo, and Yesan regions in Chungnam Province through the measuring device of the Ministry of Environment in the root region. We set up the parameters for derivation and derived an irrigation control model that can confirm the change in weight·supply liquid·drainage amount over time through the parameters.

• The Journal of shipping and logistics
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• v.34 no.4
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• pp.527-544
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• 2018

In this study, SNA analysis was conducted to examine changes in passenger movements in domestic coastal shipping. The validity of derivation of centrality rankings was enhanced by using the connection centrality that reflected weights, which had not been applied in previous research. The results of the connection centrality analysis indicated that the network composition ratio of the South Sea region was high, and the results of analysis of betweenness centrality indicated that ports belonging to the South Sea region recorded high ranks. Jeju Island, which acts as a gateway to the West Sea and the South Sea, Mokpo, which acts as a gateway between the land and islands, those ports that are geographically close to the land, and those ports that are smoothly connected to small ports, were shown to have betweenness centrality. Meanwhile, in the results of analysis of eigenvector centrality, not only ports in the South Sea region but also many ports in the West Sea region were included in the high ranked ones. Using these results, the port authority can identify major ports in domestic coastal shipping, determine the priorities support, identify the current situation of the port connection relations, and establish strategies for management of key development areas. As future studies, studies in the aspect of economy that separate general passengers and island passengers and utilize data such as fares, distances, and time are necessary.

• Journal of the Korean Geotechnical Society
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• v.34 no.12
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• pp.19-27
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• 2018

Terzaghi proposed a 2D formula for arching based on the assumption of a vertical sliding surface induced in the upper part due to the downward movement of a trapdoor. The formula was later expanded to consider 3D tunnel excavation conditions under inclined sliding surfaces. This study further extends the expanded formula to consider the effects of different ground properties and inclined sliding conditions in the transverse and longitudinal directions considering anisotropic ground conditions, as well as 3D tunnel excavation conditions. The 3D formula proposed in this study was examined of the induced vertical stress under various conditions (ground property, inclined sliding surface, excavation condition, surcharge pressure, earth pressure coefficient) and compared with the 2D Terzaghi formula. The examination indicated that the induced vertical stress increased as the excavation width and length increased, the inclination angle increased, the cohesion and friction angle decreased, the earth pressure coefficient decreased, and the surcharge pressure increased. Under the conditions examined, the stress was more affected at low excavation lengths and by the ground properties in the transverse direction. In addition, The comparison with the 2D Terzaghi formula showed that the induced vertical stress was lower and the difference was highly affected by the ground properties, inclined sliding conditions, and 3D tunnel excavation conditions. The proposed 3D arching formula could help to provide better understanding of complex arching phenomena in tunnel construction.