• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.4
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• pp.269-272
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• 2002

This study was carried out to investigate varietal differences on growth characteristics under the conditions of PE film-mulching and non-mulching in sesame. At maturing stage from 76 to 95 days after sowing, Yangbaeckkae, non-branching plant type, under non-mulching showed larger leaf area index (LAI) than that of film-mulching, while plant height and the number of capsules per plant were similar to those of film-mulching. LAI of Ahnsankkae, branching plant type, under non-mulching was similar to film-mulching, while plant height and the number of capsules per plant were smaller than those of film-mulching. Net assimilation rate (NAR) of two varieties under non-mulching was lower at seedling stage from 25 to 35 days after sowing but higher at flowering stage from 45 to 55 days after sowing. At maturing stage from 66 to 77 days after sowing, NAR and crop growth rate (CGR) of Yangbaeckkae under non-mulching were greater than those of film-mulching, whereas those of Ahnsankkae under non-mulching were lesser than those of film-mulching. Yield under non-mulching was decreased by 7 % in Yangbaeckkae and 33 % in Ahnsankkae compared with that of film-mulching, therefore Yangbaeckkae was more adaptable for non-mulching than Ahnsankkae. Main factors decreasing yield of Yangbaeckkae under non-mulching were small LAI, NAR, and CGR at the stage of young seedling, and small number of capsules at early maturing stage from first flowering to 20 days after first flowering.

• Journal of Korean Society for Atmospheric Environment
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• v.31 no.2
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• pp.181-194
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• 2015

Spatial-temporal meteorological features of the Ulsan metropolitan region (UMR) were analyzed using observations and high-resolution numerical modeling. Long-term trend analysis (1970~2013) showed a significant increase of $0.033^{\circ}Cyr^{-1}$ in the 5-year moving average temperature, although detailed short-term features varied, whereas wind speed and relative humidity over the same period displayed clear decreases of $-0.007ms^{-1}$ and $-0.29%yr^{-1}$, respectively. These trends indicate the effects of regional climate change and urbanization in the UMR. Seasonal variations averaged for the most recent three years, 2011~2013, showed that temperatures in three different regions (urban/industrial, suburban, coastal areas) of the UMR had similar seasonality, but significant differences among them were observed for a certain season. Urban and industrial complex regions were characterized by relatively higher temperatures with large differences (max.: $3.6^{\circ}C$) from that in the coastal area in summer. For wind speed, strong values in the range from 3.3 to $3.9ms^{-1}$ occurred in the coastal areas, with large differences clearly shown between the three regions in September and October. Diurnal variations of temperature were characterized by pronounced differences during the daytime (in summer) or nighttime (in winter) between the three regions. Results from the WRF modeling performed for four months of 2012 showed large variations in gridaverage temperature and winds in the UMR, which displayed significant changes by season. Especially, a clear temperature rise in the urban center was identified in July ($0.6^{\circ}C$ higher than nearby urban areas), and overall, relatively weak winds were simulated over urban and inland suburban regions in all seasons.

• Journal of Biosystems Engineering
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• v.29 no.4
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• pp.329-334
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• 2004

This study was conducted to investigate the characteristics of transmittance spectrum of Korean red ginseng using VIS/NIR spectroscopy. The results of this study were as follows; Light intensity affected the characteristics of the spectrum. For over 40% light intensity, the first and second peaks appeared at 700nm and 1,100nm, respectively. For the 20% light intensity, the first and second peaks appeared at 800nm and 1,100nm, respectively. Thus, the typical color characteristics of halogen lamp were similar to each other if over 40% of maximum light intensity power, otherwise it was not. Transmittance spectrum showed different characteristics at different portions of red ginseng. Normal red ginseng showed strong intensity at the first peak around 700nmbecause of reddish internal tissue. However, an internal white core red ginseng showed weak peak-intensity due to whitish internal tissue. There was no significant difference in the second peak at 800nm for the different internal qualities. Third peak at 900nm showed somewhat difference by internal qualities but it was difficult to find significant trend. To separate the differences of the internal qualities, intensity differences between peaks were used. It was possible to classify normal red ginseng by the differences of "peak 1 -peak 2" and "peak 1 - peak 3". In addition, shift of the first and the third peaks in the spectrum could separate normal red ginseng from others.ginseng from others.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.1
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• pp.52-56
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• 2006

This paper presents a cross-eye characteristics of multi-path wave scattering. Cross-eye method uses the phase differences of multi signals and is used fur electronic protection. When a signal is propagated from transmitter to receiver on the ground surface, direct wave and reflected wave signals are combined in front of the receiving antenna with different phases. To calculate and control the amplitude and phase of reflected signal, we have developed a cross eye electronic protection method for radar system and studied the variation of electric power density.

• Journal of the Korea Safety Management & Science
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• v.10 no.4
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• pp.111-120
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• 2008

The combustion reaction of polypropylene was investigated using a thermogravimetric technique under an air atmosphere condition at several heating rates from 10 to $50^{\circ}C/min$. To obtain information on the kinetic parameters, the dynamic thermogravimetric analysis curve and its derivative were analyzed by a variety of analytical methods such as Kissinger, Friedman, Freeman-Carroll, Chatterjee-Conrad, Ozawa and Coats-Redfern methods. The comparative works for the kinetic results obtained from various methods should be performed to determine the kinetic parameters, because there are tremendous differences in the calculated kinetic parameters depending upon the mathematical method taken in the analysis.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.10
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• pp.46-54
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• 2018

The purpose of this study is to compare and analyze differences of perceived career barriers based on demographic characteristics of cyber university students. The results of this study will provide a valuable basis for guiding adult learners in their career development. Subjects included 937 adult learners at cyber universities in Seoul, Korea, aged 20 and above. Results were as follows: The level of career barriers perceived by females aged 20-29 who were unemployed and single were higher than that of males aged 30 to 59 who were employed and married. Female students were higher in 'anxiety of future', 'lack of interest', 'lack of job information', 'interpersonal difficulty'. The only component in which subjects aged 50-59 perceived higher than other age groups was 'conflict with important people'. There was no significant differences by grade. These results imply that the perception of the career barriers of adult learners should be considered in customizing career development programs and career counselling.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.1
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• pp.518-525
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• 2016

This study examined the relationships and characteristics between generic skills and individual variables. The data from 187 students at a Korean university that participated in the Assessment of Higher Education Learning Outcomes (AHELO) feasibility study were utilized. The results indicated that there were no differences in generic skills according to gender, age, and grade point average (GPA). The field of study was the only variable showing a statistically significant difference in generic skills among the three groups. As a result of cluster analysis, four groups were formed based on the characteristics of generic skills. No differences in generic skills were observed among the four groups according to gender, age, and field of study. On the other hand, there was a statistically significant difference in generic skills among the four groups according to the GPA.

• Journal of the Ergonomics Society of Korea
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• v.35 no.5
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• pp.465-472
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• 2016

Objective:This study is on the characteristics of motorcycle accidents occurring in the mail delivery process by skill level. Background: The tendency of delivery postmen's driving in a hurry may become the cause of accidents since there is a constraint that delivery should be completed within a limited time. Method: This study analyzed the traffic accident data of 259 delivery postmen, who had been approved as occupation-related industrial accident victims from 2009 to 2012, by their work experience in view of season, day of the week of an accident occurrence, accident occurrence time, accident cause, collision type, and driving situation. Results: Accident characteristics of delivery postmen show that the ratio of accidents occurring to those who had less than 10 years of work experience was high. There were many motorcycle collisions in winter and summer by season and an unexpected object, along with road condition, took up 70.7% of the accident sources. There were no differences in accident occurrence time, the day of the week, season, accident source, and collision type between the group of delivery postmen with less than 10 years of work experience and those with 10 years or more of work experience. However, there was a difference in distribution of driving condition. Conclusion and Applications: The results of this study can be used to present the policies or guidelines for the accident prevention of delivery postmen since the results show the characteristics of the injured and accident occurrence characteristics in relation with the delivery postmen's motorcycle collisions.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.3
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• pp.90-99
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• 2016

Forecasting of box office performance after a film release is very important, from the viewpoint of increase profitability by reducing the production cost and the marketing cost. Analysis of psychological factors such as word-of-mouth and expert assessment is essential, but hard to perform due to the difficulties of data collection. Information technology such as web crawling and text mining can help to overcome this situation. For effective text mining, categorization of objects is required. In this perspective, the objective of this study is to provide a framework for classifying films according to their characteristics. Data including psychological factors are collected from Web sites using the web crawling. A clustering analysis is conducted to classify films and a series of one-way ANOVA analysis are conducted to statistically verify the differences of characteristics among groups. The result of the cluster analysis based on the review and revenues shows that the films can be categorized into four distinct groups and the differences of characteristics are statistically significant. The first group is high sales of the box office and the number of clicks on reviews is higher than other groups. The characteristic of the second group is similar with the 1st group, while the length of review is longer and the box office sales are not good. The third group's audiences prefer to documentaries and animations and the number of comments and interests are significantly lower than other groups. The last group prefer to criminal, thriller and suspense genre. Correspondence analysis is also conducted to match the groups and intrinsic characteristics of films such as genre, movie rating and nation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.2D
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• pp.303-314
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• 2011

This paper proposes a differential pricing model for industrial land based on locational characteristics, using Support Vector Regression (SVR) as a land pricing methodology. The initial selling price of industrial land is set based on the total cost of site development that comprises the land acquisition cost and tax, land development expense, infrastructure installation cost, labor cost, migration expense, selling and administrative expense, capital cost, and so on. However, the current industrial land pricing method unreasonably applies the same price per square meter to all parcels within an industrial complex without considering differences in price depending on the location of each parcel. Therefore, this paper proposes an empirical land pricing model to solve this irrationality and verifies its validity and applicability.