• Smart Media Journal
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• v.11 no.9
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• pp.21-29
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• 2022

Ultra Violet(UV) is gradually being replaced with LED instead of general UV lamps. However, the light efficiency of UV LED is still lower than that of the general lamp, and the light efficiency is also low. Due to the current environment and technical problems of UV lamps, the LED replacements are gradually being made. In this study, a new package design and analysis were performed to increase the lifetime and performance of UV LEDs. A new packaging for UV LED were designed and implemented. The new packaging for UV LED was constructed to improve light efficiency. And the electrical and optical characteristics were analyzed respectively. To improve the optical efficiency in UV LED package, the Al has been used based on high reflectivity and applying the optimal lens focusing. Compared to the existing silver Ag, the light efficiency was improved by about 30% or more, and it was confirmed that the light output degradation characteristic was improved by about 10% in the newly applied optical device chip.

• Journal of The Geomorphological Association of Korea
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• v.18 no.2
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• pp.81-98
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• 2011

Among the changes of the Curriculum from the liberation to the present, the biggest change in the highschool geography course appeared during the period from the Period of Syllabus to the 1st National Curriculum. More specifically, during the 1st National Curriculum the highschool geography course which previously had three subjects, 'Natural Environment and Human Lives', 'Human Geography', 'Economic Geography' was reduced to one subject, 'Human Geography.' In addition, while some contents related with astronomy, geology, and biology had been contained in the physiography course, they were left out from the human geography course of the 1st National Curriculum. This reduction of the geography course was related to the context that earth science was newly established in the 1st National Curriculum. Originally the draft plan released in June, 1953, which was 10 months before the formal time allotment criteria list had been made public, contained 'Physical Geography' instead of 'Earth Science'. What is sorry is that the name of 'Physical Geography' did not remain and was changed to 'Earth Science'. The underlying causes of the crisis the geography education is now facing are the reduction of Physical Geography and the emergence of 'Earth Science' during the 1st National Curriculum. To overcome the present crisis, the subject of geography should be changed more meaningful one based on the comprehensive perspective and academic product that geography has accumulated.

• Asia Marketing Journal
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• v.15 no.1
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• pp.107-128
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• 2013

When Korea's retail industry was liberalized, new store formats such as large discount stores and Super Supermarket(SSMs) have grown. New types of business have borne significant influence on traditional market. Traditional markets have been in gradual decline since they fail to meet to consumer's purchasing behavior. The South Korean government has been making sustained efforts to revitalize the modernization of traditional markets since 2004. This research is conducted to analyze how changes in the distribution of different types of distributors influence the consumer's purchasing behaviors depending on the changes in the market environment. The purpose of this research is to present a policy to invigorate consumer-oriented traditional markets by analyzing the consumption behavior among major retail channels at a point when competition among retail channels is becoming intensified. In order to examine the effect of the spatial competitive landscape among major retail channels on consumption behavior, an empirical analysis was conducted with 613 consumers in 6 cities nationwide, using the multiple regression model. This research identified three main areas of factors. The analysis result indicates that the physical factor (time required to go to the traditional market), socioeconomic factors (the number of vehicles owned and average monthly income), and competitive factors (intensity of competition in spatial locations and average monthly spending in supermarkets) have significant influence on consumption patterns of consumers. The findings present that the Korean government should go ahead with policies aimed to revitalize traditional markets, keeping in mind the factors that influence the consumption patterns of customers based on these results. We propose that the policy supporting traditional markets need to be a customized-strategy, considering traditional market's characteristic.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.4
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• pp.245-257
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• 2023

The representative crop in the Republic of Korea, rice, is cultivated over extensive areas every year, which resulting in reduced resistance to pests and diseases. One of the major rice diseases, rice blast disease, can lead to a significant decrease in yields when it occurs on a large scale, necessitating early detection and effective control of rice blast disease. Drone-based crop monitoring techniques are valuable for detecting abnormal growth, but frequent image capture for potential rice blast disease occurrences can consume significant labor and resources. The purpose of this study is to early detect rice blast disease using remote sensing data, such as drone and satellite images, along with weather data. Satellite images was helpful in identifying rice cultivation fields. Effective detection of paddy fields was achieved by utilizing vegetation and water indices. Subsequently, air temperature, relative humidity, and number of rainy days were used to calculate the risk of rice blast disease occurrence. An increase in the risk of disease occurrence implies a higher likelihood of disease development, and drone measurements perform at this time. Spectral reflectance changes in the red and near-infrared wavelength regions were observed at the locations where rice blast disease occurred. Clusters with low vegetation index values were observed at locations where rice blast disease occurred, and the time series data for drone images allowed for tracking the spread of the disease from these points. Finally, drone images captured before harvesting was used to generate spatial information on the incidence of rice blast disease in each field.

• Journal of Korea Port Economic Association
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• v.39 no.3
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• pp.191-210
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• 2023

The Covid-19 pandemic has had a significant impact on global logistics and supply chains, leading to major discrepancies in logistics performance across countries worldwide. Through an examination of logistics performance index and supply chain tracking data, this study aimed to identify the changes in global supply chains and logistics environments during the pandemic. The analysis of the logistics performance index showed that overall, countries around the world, especially developed nations, showed improvements in metrics such as customs and border management efficiency, the quality of trade and transport infrastructure, capability and quality of logistics services, and cargo tracking abilities. However, the competitive pricing feasibility of international transportation and the on-time delivery frequency of goods saw a decline due to the pandemic's effects. The supply chain tracking data revealed that ports in Asian countries demonstrated high processing efficiency. In contrast, the U.S. and European countries took comparatively more time. Particularly for air cargo, parcels, and express shipments, the U.S. showed relatively longer processing times, leading to logistical delays. In conclusion, during the Covid-19 pandemic, Asian countries maintained relatively high efficiency in their logistics and trade environments. Conversely, the U.S. and some European countries showed delays and decreased efficiency in various metrics. In the future, efforts should be made to address delays and congestion, namely, the deceleration of logistics processes.

• Korean Journal of Heritage: History & Science
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• v.56 no.4
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• pp.6-22
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• 2023

The National Museum of Korea's 'Shinchungmyeong Jochong' is the sole firearm in the country bearing inscriptions written in ink('辛丑改備江華庫藏'). Thanks to this written record, it is possible to determine where this firearm was stored and to make an estimate of the time when it was stored. Additionally, it is a valuable artifact that has been exceptionally well preserved and has an artistic design. However, research into the operational period, form, and structural characteristics of this firearm has been limited to date. This study aimed to shed light on the operational period, form, and structural features of the 'Shinchukmyeong Jochong.' To achieve this, the specifications and structural characteristics of the firearm were examined, and comparisons were made with 17 other extant firearms and their attributes. The results confirmed that the 'Shinchungmyeong Jochong' is a representative example of the typical firearms of the Joseon Dynasty. Next, the timing, background, and production subject of the Ganghwado containment of the Jochong were tracked based on letters found with the Jochong. The investigation revealed an entry in the 'Records of King Jeongjo'(『正祖實錄』) indicating that a significant amount of military supplies, including firearms, were stored on Ganghwado in December of the 5th year of Shinchung(1781). The decision to store these materials in Ganghwado Island may have been due to the perception of the Joseon decision-makers, who strategically valued Ganghwado Island, and the relocation of 'Tongaoyeong'(統禦營) and the integration with 'Jinmuyeong'(鎭撫營). After acquisition, it is presumed that the firearm was operated at locations like 'Jinmuyeong'(鎭撫營). The firearm's production is presumed to have been associated associated with institutions such as 'Gungisi'(軍器寺). In conclusion, the 'Shinchungmyeong Jochong' exemplifies a typical firearm of the Joseon Dynasty, and it is likely that it was stored on Ganghwado in December of 1781. Its production is believed to have been related to institutions such as 'Gungisi'. Following its acquisition, it is presumed that the firearm was operated at locations including 'Jinmuyeong'.

• Journal of the Korean Association of Geographic Information Studies
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• v.26 no.4
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• pp.97-115
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• 2023

In recent years, the structure of the population has been changing rapidly, with a declining birthrate and aging population, and the inequality of population distribution is expanding. At this point, changes in population estimation methods are required, and more accurate estimates are needed at the subregional level. This study aims to estimate the population in 2040 at the 500m grid level by applying an explainable machine learning to Busan in order to respond to this need for a change in population estimation method. Comparing the results of population estimation by applying the explainable machine learning and the cohort component method, we found that the machine learning produces lower errors and is more applicable to estimating areas with large population changes. This is because machine learning can account for a combination of variables that are likely to affect demographic change. Overestimated population values in a declining population period are likely to cause problems in urban planning, such as inefficiency of investment and overinvestment in certain sectors, resulting in a decrease in quality in other sectors. Underestimated population values can also accelerate the shrinkage of cities and reduce the quality of life, so there is a need to develop appropriate population estimation methods and alternatives.

• Journal of The Korean Association For Science Education
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• v.28 no.2
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• pp.130-138
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• 2008

The purpose of this study was to analyze the effects of Science Writing Heuristic(SWH) strategy on problem-solving type inquiry modules through student-student verbal interactions. The modules were applied to 23 students of the 3rd grade in middle school and the SWH strategy was applied to 3 experimental groups. The SWH is the strategy that each student, first of all, has a chance to think and propose ways of problem-solving by individual writing a blue card when problems were emerged, and then students discuss ways of problem-solving with group members by writing a green card. Verbal interactions during small group discussions were audio- and video-taped, transcribed and analyzed to compare the effect of the SWH strategy. As a results, experimental groups tended to force solely on questions and suggestions about problem-solving, but controlled groups executed experiment and discussed about problem-solving simultaneously. The analysis also showed that the experimental students dialogued more on the deep-leveled argumental interactions than the controlled students did; in particular, show more SS3 and SD1 verbal interaction regarding suggestions of problem solving. We argue, therefore, that the SWH strategy is effective to the problem-solving type inquiry modules.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.4
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• pp.342-347
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• 2008

Mortality and growth rate of the soft coral, Dendronephthya gigantea, from Jejudo Island on the southern coast of Korea were investigated from February 2003 to October 2004 using SCUBA diving. 48 individuals with variable sizes of D. gigantea of the depth of 15m were tagged with flagging tapes and plastic films, and then monitored with two month intervals. The average mortality of two-month term for the study period was 50.4%, with the peak of 84.6% during the summer storms in August - October 2003. About the size class mortality, individuals of size class I(${\leq}$10 cm) showed the highest mortality, followed by size class III(>20 cm) and size class II(10 cm-20 cm). Growth rate did not show a seasonal pattern. For growth in length, individuals of D. gigantea grew about 3cm in average for two-month period, with a maximum growth of 6.4 cm which occurred in August - October 2003. For growth in diameter, individuals grew about 0.3 cm for 2 month term, with a maximum of 1.4cm in April - June 2004. Individuals of size class I usually grew faster than those of larger size classes. D. gigantea population in Jejudo Island was strongly affected by summer storms, which was due to annual event of summer typhoon. Never the less, it appears that the local population can be maintained by fast growth of the juvenile stage and active recruitment to compensate the high mortality caused by the summer disturbance.

• Industry Promotion Research
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• v.9 no.1
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• pp.39-45
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• 2024

Dangerous tasks that occur every day at industrial site manufacturing plants, which have recently been making rapid changes, were classified by type, and the effect of mobile circuit television (CCTV) on safety accidents among daily safety management methods was analyzed. The subject of the study is about 3,000 workers who manage the infrastructure facility sector to supply utilities such as gas, water, and electricity to the display manufacturing process located in Asan City, and the study was conducted based on the daily dangerous work from 2019 to 2022, and during this study period, many construction works such as new investment and expansion of construction and manufacturing processes were occurring at the site. As a result, the rate of safety accidents and exposure to risks are expanding, and most of the safety accidents occurred because the sectors that did not follow the basics and the safety measures on the site were not implemented. In this paper, it was confirmed that there is an accident reduction effect according to the relationship between the dangerous work classified according to the work importance and the mobile CCTV shooting rate. Considering the characteristics of the manufacturing plant site, it can be used to play the role of basic data for preventing safety accidents based on the expansion of the introduction of a new safety management culture in the future.