• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.39 no.4
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• pp.347-357
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• 2003

This paper describes on the suppression of sea clutter on marine radar display using a cell-averaging CFAR(constant false alarm rate) technique, and on the analysis of radar echo signal data in relation to the estimation of ARPA functions and the detection of the shadow effect in clutter returns. The echo signal was measured using a X -band radar, that is located on the Pukyong National University, with a horizontal beamwidth of $$3.9^{\circ}$$, a vertical beamwidth of $20^{\circ}$, pulsewidth of $0.8 {\mu}s$ and a transmitted peak power of 4 ㎾ The suppression performance of sea clutter was investigated for the probability of false alarm between $l0-^0.25;and; 10^-1.0$. Also the performance of cell averaging CFAR was compared with that of ideal fixed threshold. The motion vectors and trajectory of ships was extracted and the shadow effect in clutter returns was analyzed. The results obtained are summarized as follows；1. The ARPA plotting results and motion vectors for acquired targets extracted by analyzing the echo signal data were displayed on the PC based radar system and the continuous trajectory of ships was tracked in real time. 2. To suppress the sea clutter under noisy environment, a cell averaging CFAR processor having total CFAR window of 47 samples(20+20 reference cells, 3+3 guard cells and the cell under test) was designed. On a particular data set acquired at Suyong Man, Busan, Korea, when the probability of false alarm applied to the designed cell averaging CFAR processor was 10$^{-0}$.75/ the suppression performance of radar clutter was significantly improved. The results obtained suggest that the designed cell averaging CFAR processor was very effective in uniform clutter environments. 3. It is concluded that the cell averaging CF AR may be able to give a considerable improvement in suppression performance of uniform sea clutter compared to the ideal fixed threshold. 4. The effective height of target, that was estimated by analyzing the shadow effect in clutter returns for a number of range bins behind the target as seen from the radar antenna, was approximately 1.2 m and the information for this height can be used to extract the shape parameter of tracked target..

• Korean Journal of Health Education and Promotion
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• v.23 no.4
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• pp.125-153
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• 2006

This study was intended to describe women's weight controlling by creating a hypothetic model on the weight adjustment behavior and by examining a cause and effect relationship, and to contribute to countermeasures for practicing their promotion of health and improving the quality of life through creating a predictable model. The subject of study was women who utilize the beauty shop located in Seoul, Busan and Daegu and the study period was 12 weeks from July 10 to September 30 in 2004. Gathered 1093 person's general specialty related with weight adjustment and analyzed covariance to prove the hypothesis using statistics compiled from authentic sources. Also proved coincidence of the hypothetical model. Exogenous variables of the hypothetical model are composed of recognition of her body shape, fatness level, age, stress, and self-respect. Endogenous variables are health- control mind, recognized health state, self-efficacy, intention, and behavior of weight adjustment. There were 5 measured variables for exogenous variable(x). There were 8 measured variable(y) for exogenous variable. And coincidence $x^2=297.38$, standard $x^2(x^2/df)=7.08$, GFI=0.962, AGFI=0.917, NFI=0.875, TLI=0.794, CFI=0.889, RMSEA=0.075. The result of hypothesis had an epoch-making record that 20 out of 27 hypothesis was proved positive way. Generally weight adjustment has been highly seen in housewives, the married and the old age. Health control mind seems to be high as fatness level, age, and self-respect are high and low stress. Recognized health state is high as age and self-respect are high and low stress. However, it is not much related with recognition of her body shape and fatness level. If age, self-respect, health control mind, recognized health state and self-efficacy are high intention of behavior is also high, but intention of behavior has no relation with recognition of her body shape, fatness level and stress. If fatness level, age, self-respect, health control mind, recognized health state and self-efficacy and intention of behavior are high, execution of weight adjustment will be high. However, recognized health state and stress has no influence for weight adjustment. To increase the coincidence of hypothesis and take a simple model I modified a model and then I got the coincidence $x^2=215.62$, standard $x^2(x^2/df)=6.34$, GFI=0.970, AGFI=0.931, NFI=0.902, TLI=0.901, CFI=0.915, RMSEA=0.070. This result is a bit better than original hypothetical model's so that this model might be more suitable. In this modification model, the factors of weight adjustment seems to be high according to this order self-efficacy, recognized health state, age, intention, health control mind, self-respect, fatness level and stress. With this result I suggest ; 1. Enforcement of IR that everybody can be controlled weight adjustment herself and continuous education, which is related with regular habit (food, exercise, restriction of a favorite food and behavior training etc.) is also needed. 2. Because self-efficacy is influenced to execution of weight adjustment specific program which can increase self-efficacy should have to develop and we need to utilize it to take care of herself. 3. To protect fatness and be active weight adjustment the peculiar program including the concept of self-respect, recognized health state, health control mind and intention must be developed and not only women but also all of people should be educated. 4. This hypothetical model is forecasting women's weight adjustment behavior and can be utilized for fundamental data to increase those people's health.

• The Journal of the Petrological Society of Korea
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• v.18 no.3
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• pp.223-236
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• 2009

Ultramafic xenoliths from southeastern part of Jeju Island can be grouped into two types: Type I and Type II. Type I xenoliths are magnesian and olivine-rich peridotite (mg#=89-91), which are commonly found at the outcrop. Most previous works have been focused on Type I xenoliths. Type II xenoliths, consisting of olivine, orthopyroxene and clinopyroxene with higher Fe and Ti components (mg#=77-83) and lower Mg, Ni, Cr, are reported in this study. They are less common with a more extensive compositional range. The studied Type II xenoliths are wehrlite, olivine-clinopyroxenite, olivine websterite, and websterite. They sometimes show ophitic textures in outcrops indicating cumulate natures. The textural characteristics, such as kink banding and more straight grain boundaries with triple junctions, are interpreted as the result of recrystallization and annealing. Large pyroxene grains have exsolution textures and show almost the same major compositions as small exsolution-free pyroxenes. Although the exsolution texture indicates a previous high-temperature history, all mineral phases are completely reequilibrated to some lower temperature. Orthopyroxenes replacing clinopyroxene margin or olivine indicate an orthopyroxene enrichment event. Mineral phases of Type II are compared with Type I xenoliths, gabbroic xenoliths, and the host basalts. Those from Type II xenoliths show a distinct discontinuity with those from Type I mantle xenoliths, whereas they show a continuous or overlapping relation with those from gabbroic xenoliths and the host basalts. Our petrographic and geochemical results suggest that the studied type II xenoliths appear to be cumulates derived from the host magma-related system, being formed by early fractional crystallization, although these xenoliths may not be directly linked to the host basalt.

• Korean Journal of Soil Science and Fertilizer
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• v.3 no.1
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• pp.17-21
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• 1970

To determine the effects of the silicate and the phosphate on the rice seedlings, 200 grams dry soil of the paddy field taken in the petri dish of 15cm diameter were treated with three levels of silicate(wollastonite) and phosphate. And the same amounts of nitrogen and potash were added constantly to each treated petridish. 100 grains of rice of which variety is Nongrim 25 were sown on each treated petridish simultaneously. After five times continuous culture, the rice plants and the soil were analyzed chemically and the results obtained are summarized as follows: 1. Dry matter weight of the rice seedlings was significantly increased to the increased phosphate absorption, on the other hand that was decreased when the silica absorption was increased. 2. The higher the available phosphate content in the soil after the experiments, the lower the silica content as well as absorption by the plant, and the $SiO_2/P_2O_5$ ratio in the plant was significantly decreased. 3. By the wollastonite application, the available silica, the exchangeable calcium in the soil after the experiment, and the silica content as well as silica absorption and $SiO_2/P_2O_5$ ratio in the rice plant was significantly increased. 4. Higher correlation coefficient was obtained between the exchangeable calcium amount and the silica content or silica/phosphate ratio in the rice plant than the available silica content in soil itself. 5. It is possible to control the silica/phosphate ratio in plant by the control of the silica/phosphate ratio in soil. 6. The relation between the silica/phosphate ratio in plant (y) and the available silica/phosphate ratio in soil (x) was $y=0.665+1.420x-0.0825x^2$ and the goodness of fit(r) was 82%.

• Journal of the Korean Association of Geographic Information Studies
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• v.24 no.2
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• pp.12-28
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• 2021

Based on the global smart city promotion trend, in 2018, the "Fourth Industrial Revolution Committee" selected "sustainability" and "people-centered" as keywords in relation to the direction of domestic smart city policy. Accordingly, the Living Lab program, which is an active citizen-centered innovation methodology, is applied to each stage of the domestic smart city construction project. Through the Living Lab program, and in collaboration with the public and experts, the smart city discovers local issues as it focuses on citizens, devises solutions to sustainable urban problems, and formulates a regional development plan that reflects the needs of citizens. However, compared to citizen participation in urban regeneration projects that have been operated for a relatively long time, participation in smart city projects was found to significantly differ in level and sustainability. Therefore, this study conducted a comparative analysis of the characteristics of citizen participation at each stage of an urban regeneration project and, based on Arnstein's "Participation Ladder" model, examined the level of citizen participation activities in the Living Lab program carried out in a smart city commercial area from 2018 to 2019. The results indicated that citizen participation activities in the Living Lab conducted in the smart city project had a great influence on selecting smart city services, which fit the needs of local residents, and on determining the technological level of services appropriate to the region based on a relatively high level of authority, such as selection of smart city services or composition of solutions. However, most of the citizen participation activities were halted after the project's completion due to the one-off recruitment of citizen participation groups for the smart city construction project only. On the other hand, citizens' participation activities in the field of urban regeneration were focused on local communities, and continuous operation and management measures were being drawn from the project planning stage to the operation stage after the project was completed. This study presented a plan to revitalize citizen participation for the realization of a more sustainable smart city through a comparison of the characteristics and an examination of the level of citizen participation in such urban regeneration and smart city projects.

• Korean journal of applied entomology
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• v.24 no.3 s.64
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• pp.123-127
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• 1985

Incidence of the Fusarium wilt caused by F. oxysporum f. sp. vasinfectum of sesame (var. Kwangsan) was remarkably influenced by seeding date and mean air temperature in the field of two or three year's continuous cropping with sesame in 1983 and 1985. Sesame were seeded on six different dates from April 20 to July 5. Air temperature was checked daily at the meteorological station near the experimental field. Low($16{\sim}20^{\circ}C$) and high temperature($20{\sim}25^{\circ}C$) periods were provisionally devided, based on every ten-day mean daily temperature during field experiment for last ten years, which corresponded to before and after June 15 in Jinju, Gyeong-nam. Infection rates were 83.7%, 68.2% and 59.4% in the plants grown for 55 days (seeding date: April 20), 40 days(May 5) and 25 days(May 20) under low temperature. On the other hand, infection rates were below 3% in those plots seeded during high temperature period. The longer the growth period exposed to low temperature, the higher was infection rates. It is interesting to note that 40 days old seedling or older are prone to severe infection compared to the younger ones, in higher temperature of $20{\sim}25^{\circ}C$. Therefore, seedlings in vegetative growth stage are less prone to infection than these in reproductive growth stage. The result showed that air temperature during sesame growth was one of the most important factor affecting the incidence of Fusarium wilt. This suggested that sesame crop, which is of tropical origin, has been predisposed to Fusarium wilt, when the plants were exposed to low temperature of $16{\sim}20^{\circ}C$.

• Journal of Navigation and Port Research
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• v.47 no.3
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• pp.147-154
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• 2023

This study aims to determine the necessity, role, utilization, and operation and management plan in relation to the underwater space platform where humans can newly reside. It provides a comprehensive opinion on the need for creating undersea space and operation plans based on opinions of industry-university-affiliated organizations involved in the R&D project of the Ministry of Maritime Affairs and Fisheries for the utilization of undersea space and external experts participating in marine technology development. In this study, a survey was conducted on researchers participating in the construction of a Korean submarine space platform. FGI was conducted on marine technology development experts. Results were then derived. As a result of the analysis, the need for subsea space construction was found to be high. As for the role of subsea space, the most common opinion was to develop technology for utilizing subsea space and to secure marine science research functions. It was found that the creation of subsea space would have a positive impact on the domestic industry, especially the deep-sea development industry and the shipbuilding/offshore structure industry. In terms of utilization, after the end of the seabed space test bed, the response to utilization as a marine observation base and marine ecosystem research had the highest proportion. As for expected inconvenience, discomfort in the psychological environment was the highest. Experts suggest that securing a continuous budget is most important for stable operation in the future and that securing a manpower budget is essential for itemized budgets. In addition, it was judged that it would be appropriate to establish a prior agreement from the time of the prior agreement and prepare a countermeasure before proceeding with the project in order to ensure ownership issues, consignment management issues, and cost issues when using the project after the end of the project.

• Economic and Environmental Geology
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• v.56 no.5
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• pp.589-601
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• 2023

We compare high-resolution seabed bathymetry data and seafloor backscattering data acquired, using multi-beam, between 2018 and 2021 to understand topographic changes in the coastal area of Dokdo. The study area, conducted within a 500 m × 500 m in the southern coast between the islands where Dongdo Port is located, has been greatly affected by human activities, waves and ocean currents. The depth variations exhibit between 5 - 70 m. Irregular underwater rocks are distributed in areas with a depth of 20 m or less and 30 - 40 m. As a whole, water depth ranges similar in the east-west direction and become flatter and deeper. The bathymetry contour in 2020 tends to move south as a whole compared to 2018 and 2019. The south moving of the contours in the survey area indicates that the water depth is shallower than before. Since the area where the change in the depth occurred is mainly formed of sedimentary layers, the change in the coast of Dokdo were mainly caused by the inflow of sediments, due to the influence of wind and waves caused by these typhoons (Maysak and Haishen) in 2020. In the Talus area, which developed on the shallow coast between Dongdo and Seodo, the bathymetry changed in 2020 due to erosion or sedimentation, compared to the bathymetry in 2019 and 2018. It is inferred that the changes in the seabed environment occur as the coastal area is directly affected by the typhoons. Due to the influence of the typhoons with strong southerly winds, there was a large amount of sediment inflow, and the overall tendency of the changes was to be deposited. The contours in 2021 appears to have shifted mainly northward, compared to 2020, meaning the area has eroded more than 2020. In 2020, sediments were mainly moved northward and deposited on the coast of Dokdo by the successive typhoons. On the contrary, the coast of Dokdo was eroded as these sediments moved south again in 2021. Dokdo has been largely affected by the north wind in winter, so sediments mainly move southward. But it is understood that sediments move northward when affected by strong typhoons. Such continuous coastal change monitoring and analysis results will be used as important data for longterm conservation policies in relation to topographical changes in Dokdo.

• Journal of Korea Port Economic Association
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• v.39 no.4
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• pp.23-42
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• 2023

This study is to investigate the influence relationship between ethical management activities and organizational effectiveness of logistics companies and the regulatory role of organizational trust and self-esteem in the relationship between the two variables. An empirical study was conducted through a survey of 270 employees of a logistics company, and the results of the study are as follows. First, the hypothesis that ethical management activities of logistics companies will affect organizational effectiveness was adopted. Among the ethical management activities of logistics companies, personnel management activities influenced organizational commitment and turnover intention, and external ethical management activities affected customer orientation and organizational commitment. Second, the hypothesis that trust and pride in an organization will affect organizational effectiveness was adopted. Trust in the company influenced organizational business and intention to leave, and trust and pride in superiors affected customer orientation and organizational commitment. Third, in the relationship between ethical management activities and organizational effectiveness of logistics companies, organizational trust and self-esteem have a role in controlling. The hypothesis was partially accepted. Organizational trust and pride of workers in logistics companies have the largest moderating effect on turnover intention in the relationship between ethical management activities and organizational effectiveness. In particular, it can be confirmed that self-esteem has a moderating effect on all variables such as customer orientation, organizational commitment and turnover intention. Based on the above analysis results, logistics companies can see the effect of increasing organizational effectiveness (customer orientation, organizational commitment, turnover intention) through ethical management activities, organizational trust and pride. In relation to effectiveness, since the role of controlling the turnover intention of employees of logistics companies is the greatest, it is necessary to apply this to the organizational management program to increase the efficiency of organizational management through fair and transparent continuous operation.

• Journal of Korean Society of Forest Science
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• v.75 no.1
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• pp.1-18
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• 1986

This study was initiated to estimate productivity of Quercus variabilis stand. However the practical objective of this study was to provide some information to establish the basis of selecting the suitable site for Quercus variabilis. The productivity measured in terms of DBH, height, basal area and stem volume was hypothesized, respectively, to be a function of a group of factors. This study considered 32 factors, 20 of which were related to the forest environmental factors such as tree age, latitude, percent slope, etc. and the rest of which were related to soil factors such as soil moisture, total nitrogen, available $P_2O_5$, etc. The data on 4 productivity measurements of Quercus variabilis growth and related factors cited were collected from 99 sample plots in Kyeongbook and chungbook provinces. Some factors considered were, in nature, discrete variables and the others continuous variables. Each kind of factor was classified into 3 or 4 categories and total numbers of such categories were eventually amounted to 110. Then each category was treated as an independent variable. This is amounted to saying that individual variable was treated a dummy variable and assigned a value 1 or 0. However the first category of each factor was deleted from the normal equation for statistical consideration. First of all, each of 4 productivity measurements of Quercus variabilis growth was regressed and, at the same time, those 110 categories. Secondly, the partial correlation coefficients were measured between each pair of 4 productivity measurements and 32 individual foctors. Finally, the relative scores were estimated in order to derive the category ranges. The result of these statistical analyses could be summarized as follows: 1) Growth measurement in terms of height seems to be a more significant criterion for estimation of productivity of Quercus variabilis. 2) Productivity of forest on stocked land may better be estimated in terms of forest environmental factors, on the other hand, that of unstocked land may be estimated in terms of physio-chemical factors of soil. 3) The factors that a strongly positive relation to all growth factors of tree are age group, effective soil, soil moisture, etc. This implies that these factors might effectively be used for criteria for selecting the suitable site for Quercus variabilis. 4) Parent rock, latitude, total nitrogen, age group, effective soil depth, soil moisture, organic matter, etc., had more significant category range for tree growth. Therefore, the suitable site for Quercus variabilis may be selected, based on this information. In conclusion, the above results obtained by the multivariable analysis can be not only the important criteria for estimating the growth of Quercus variabilis but also the useful guidance for selecting the suitable sites and performing the rational of Quercus variabilis forest.