• Korean Journal of Remote Sensing
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• v.36 no.2_1
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• pp.217-229
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• 2020

Recently, weather changes in Korea have intensified due to global warming, and the five major natural disasters that occur mostly include heavy rains, typhoons, storms, heavy snow, and earthquakes. Busan is vulnerable to snow disaster, given that the amount of natural disaster damage in Busan accounts for more than 50% of the total amount in the entire metropolitan cities in Korea, and that the Busan area includes many hilly mountains. In this study, we attempted to identify vulnerable areas for snowfall disasters in Busan areas using the geographic information system (GIS) with the data for both geographical and anthropogenic characteristics. We produced the maps of vulnerable areas for evaluating factors that include altitude, slope, land cover, road networks, and demographics, and overlapped those maps to rank the vulnerability to snowfall disasters as the 5th levels finally. To weight each evaluating factor, we used an entropy method. The riskiest areas are characterized by being located in mountainous areas with roads, including Sansung-ro in Geumjeong-gu, Mandeok tunnel in Buk-gu, Hwangnyeongsan-ro in Suyeong-gu, and others, where road restrictions were actually enforced due to snowfall events in the past. This method is simple and easy to be updated, and thus we think this methodology can be adapted to identify vulnerable areas for other environmental disasters.

• The Journal of Art Theory & Practice
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• no.13
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• pp.7-33
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• 2012

The memory of the Korean War is about the time period when people lived toughly during evacuation, due to being exposed to the natural climate such as intense cold or heat without any protection, leaving their comfortable home and living in temporary built shelters which were barely enough to avoid the wind. 'Death is concealed and only the figures of evacuation for survival were expressed, just as how the government ordered. Since the experience of the battlefield is personal and fragmentary, that is broken into pieces, it does not have compatibility. As war is a distorted experience that cannot be placed in a big picture, it is not possible to take a view of the war's big picture. Having this individualized experience as a common collective memory is an issue and it is the will that people tries to pursue. The reason why the evacuees from north to south, and as well as from the south to further south were all able to be adopted as the theme of artworks due to the military action that emptied the occupied territories of the North Korean Army under the forced removal command. In such situations, the natural state of the 'snow' was like a symbol of the 1.4 Recession. The group of people who were thrown into the intense cold displaced the war damage of loosing their base livelihood, and symbolized the obedient citizens who faithfully follow their government's command. The figure of advocating anti-communism is projected as a figure of a refugee during cold winter-time and it contains ones past which he or she obeyed its own country's commands. Evacuation, especially the evacuation during the winter is a visual device that can confirm these kinds of country's command. The consequences were same for the artists as well. Therefore, the situation being communal could be found due to the individual experiences during war are ideological. The image of the refuge shown in the picture played the role of strengthening the consciousness of defecting to South Korea into the meaning of the 'Finding Freedom.' I would like to express that the reason of them leave their home during the harsh winter is in order to avoid the oppression of the Communist Party. The evacuation that people went through was not to 'Finding Freedom', but 'To Survive'. Later, this evacuation has been imprinted as a behavior of choosing free Republic of Korea, which was an ideological issue. Anti-communism was the rule of survival in South Korea society, and people have the tendency to remember what they want to remember. As it is not the people who possesses an incident, but the memory that possesses ones, people cover their memory with disguised plots in order to forget the violence and to live a different prologue. They share the incident of violence as a hurtful memory. The tragedy of the Korean War was the result of Ideology and being in between the powerful nations' rights, but the violence during the war has been depicted as a natural disaster, which was the evacuation in heavy snow.

• Asian Journal of Turfgrass Science
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• v.25 no.2
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• pp.133-137
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• 2011

Winterkill can be defined as any injury including freeze stress kill, winter desiccation, and low temperature disease to turfgrass plants that occurs during the winter period. The major damages from winterkill were low temperature kill, crown hydration, and winter desiccation. Low temperature kill is caused by air and soil temperature. Soil temperature affect more severe to turfgrass than air temperature because low soil temperature cause fetal damage to turfgrass crown. Crown hydration is a form of winter injury in which intercellular water within the plant freezes and causes physical injury to the cell membrane and wall. This is eventually resulted in dehydration of cell. Winter desiccation is the death of leaves or whole plants due to drought during the winter period. To reduce winterkill damage, cultivar selection is very important. If changing cultivar is not allowed, cold temperature hardiness needs to be increased by providing nutrients especially phosphorus and potassium in the late fall. Turf cover is effective way to reduce winterkill damage. Remaining snow is positive process to reduce winterkill damage by insulating soil temperature. The previous researches reported many materials as turf cover such as straw, polypropylene, polyester, and wood mat. Aeration and topdressing is one of the process against winterkill. Both methods are mainly conducted to reduce thickness of thatch layer. In recent, relatively new materials called black or winter topdressing sand are used to protect soil temperature from low air temperature and thaw ice crystal that may remain in soil.

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.4
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• pp.52-67
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• 2020

Recently, the Arctic has been exposed to snow-covered land due to melting permafrost every year, and the Korea Geographic Information Institute(NGII) provides polar spatial information service by establishing spatial information of the polar region. However, there is a lack of spatial information on vegetation sensitive to climate change. This research used a multi-temporal Sentinel-2 image to perform land cover classification of the Ny-Ålesund in Arctic Svalbard. In the pre-processing step, 10 bands and 6 vegetation spectral index were generated from multi-temporal Sentinel-2 images. In image-classification step is consisted of extracting the vegetation area through 8-class land cover classification and performing the vegetation species classification. The image classification algorithm used Random Forest to evaluate the accuracy and calculate feature importance through Out-Of-Bag(OOB). To identify the advantages of multi- temporary Sentinel-2 for vegetation classification, the overall accuracy was compared according to the number of images stacked and vegetation spectral index. Overall accuracy was 77% when using single-time Sentinel-2 images, but improved to 81% when using multi-time Sentinel-2 images. In addition, the overall accuracy improved to about 83% in learning when the vegetation index was used additionally. The most important spectral variables to distinguish between vegetation classes are located in the Red, Green, and short wave infrared-1(SWIR1). This research can be used as a basic study that optimizes input characteristics in performing the classification of vegetation in the polar regions.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.1D
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• pp.23-31
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• 2012

Busan Metropolitan City government has been implementing the local Bus Quasi-Public Operating policy since 2007. As a result of the policy, financial burden to cover financial deficit has become a big social issue. For successful settlement of the policy, the government should be able to gradually cut off the financial support for the deficit by continuously increasing the bus demand, which can be accomplished by providing more convenient bus services. The weather conditions that affect the public transportation demand include rain, fog and snow. They affect the mode choice for public transportation use, which in turn results in decrease in bus demand. In short, the adverse weather conditions result in significant profit loss of bus transportation, and consequently it financially burdens the City of Busan. In this research, the pattern of travelers' use of transportation modes given various weather conditions was analyzed. In addition, the reasons why people transfer from one to other transportation modes were analyzed by conducting a field survey, and policy implications on desirable public transportation facilities and transfer system were discussed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.131-136
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• 2004

The limited slip differential(LSD) is a device which enables the driving force to be transmitted from one slipping wheel to another wheel in such case that the car is stuck in clay or snow. When the unwanted slipping occurs on one wheel, the LSD temporarily restraints the differential motion to transmit the driving force in the other wheel. So far, many types of LSD were developed such as mechanical lock type, disk clutch type, viscous coupling type, torsion type and multiple clutch type. However these types of LSD is too complicated and expensive, so it is used only for 4WD outdoor vehicles, military vehicles, and a portion of deluxe car. So, many studies has been devoted to improve new types of LSD to cover those demerits of existing LSDs that the hydraulic LSD is developed as arepresentative result of that. The hydraulic LSD which uses the principle of gear pump is packed with viscous oil in tight container. When a slip occurs on one wheel, the hydraulic LSD generates torque caused by high oil pressure in the container. This study has been devoted to suggest an improved hydraulic LSD. In order to achieve it, we designed a new type of hydraulic LSD, produced it and did a rig test with it on real vehicle. From the rig test, it has been confirmed that the new type of hydraulic LSD can be directly applied to exiting vehicles without changing the design criteria

• The Korean Journal of Quaternary Research
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• v.17 no.2
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• pp.47-54
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• 2003

Climate of Mongolia is a driven force on natural conditions as well as socio-economic development of the country. Due to the precariousness of climate conditions and traditional economic structure, natural disasters, specially disasters of meteorological and hydrological origin, have substantial effect upon the natural resources and socio-economic sectors of Mongolia. Mongolia's climate is characterized by high variability of weather parameters, and high frequency and magnitude of extreme climate and weather events. During the last few decades, climate of the country is changing significantly under the global warning. The annual mean air temperature for the whole territory of the country has increased by $1.56^{\circ}C$ during the last 60 years,. The winter temperature has increased by $1.56^{\circ}C$. These changes in temperature are spatially variable: winter warming is more pronounced in the high mountains and wide valleys between the mountains, and less so in the steppe and Gobi regions. There is a slight trend of increased precipitation during the last 60 years. The average precipitation rate is increased during 1940-1998 by 6%. This trend is not seasonally consistent: while summer precipitation increased by 11 %, spring precipitation decreased by 17. The climate change studies in Mongolia show that climate change will have a significant impact on natural resources such as water resources, natural rangeland, land use, snow cover, permafrost as well as major economic activities of arable farming, livestock, and society (i.e. human health, living standards, etc.) of Mongolia. Therefore, in new century, sustainable development of the country is defined by mitigating and adaptation policies of climate change. The objective of the presentation is to contribute one's idea in the how to reflect the changes in climate system and weather extreme events in the country's sustainable development concept.

• 한국환경농학회:학술대회논문집
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• 2009.07a
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• pp.228-239
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• 2009

The observations on climate change show a clear increase in the temperature of the Earth's surface and the oceans, a reduction in the land snow cover, and melting of the sea ice and glaciers. The effects of climate change are likely to include more variable weather, heat waves, increased mean temperature, rains, flooding and droughts. The threat of climate change and global warming on human and animal health is now recognized as a global issue. This presentation is described an overview of the latest scientific knowledge on the impact of climate change on zoonotic diseases. Climate strongly affects agriculture and livestock production and influences animal diseases, vectors and pathogens, and their habitat. Global warming are likely to change the temporal and geographical distribution of infectious diseases, including those that are vector-borne such as West Nile fever, Rift Valley fever, Japanese encephalitis, bluetongue, malaria and visceral leishmaniasis, and other diarrheal diseases. The distribution and prevalence of vector-borne diseases may be the most significant effect of climate change. The impact of climate change on the emergence and re-emergence of animal diseases has been confirmed by a majority of countries. Emerging zoonotic diseases are increasingly recognized as a global and regional issue with potential serious human health and economic impacts and their current upward trends are likely to continue. Coordinated international responses are therefore essential across veterinary and human health sectors, regions and countries to control and prevent emerging zoonoses. A new early warning and alert systems is developing and introducing for enhancing surveillance and response to zoonotic diseases. And international networks that include public health, research, medical and veterinary laboratories working with zoonotic pathogens should be established and strengthened. Facing this challenging future, the long-term strategies for zoonotic diseases that may be affected by climate change is need for better prevention and control measures in susceptible livestock, wildlife and vectors in Korea. In conclusion, strengthening global, regional and national early warning systems is extremely important, as are coordinated research programmes and subsequent prevention and control measures, and need for the global surveillance network essential for early detection of zoonotic diseases.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.441-444
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• 2008

This paper describes the development of a circularly polarized microstrip antenna, as a part of the Circularly Polarized Synthetic Aperture Radar (CP-SAR) sensor which is currently under developed at the Microwave Remote Sensing Laboratory (MRSL) in Chiba University. CP-SAR is a new type of sensor developed for the purpose of remote sensing. With this sensor, lower-noise data/image will be obtained due to the absence of depolarization problems from propagation encounter in linearly polarized synthetic aperture radar. As well the data/images obtained will be investigated as the Axial Ratio Image (ARI), which is a new data that hopefully will reveal unique various backscattering characteristics. The sensor will be mounted on an Unmanned Aerial Vehicle (UAV) which will be aimed for fundamental research and applications. The microstrip antenna works in the frequency of 1.27 GHz (L-Band). The microstrip antenna utilized the proximity-coupled method of feeding. Initially, the optimization process of the single patch antenna design involving modifying the microstrip line feed to yield a high gain (above 5 dBi) and low return loss (below -10 dB). A minimum of 10 MHz bandwidth is targeted at below 3 dB of Axial Ratio for the circularly polarized antenna. A planar array from the single patch is formed next. Consideration for the array design is the beam radiation pattern in the azimuth and elevation plane which is specified based on the electrical and mechanical constraints of the UAV CP-SAR system. This research will contribute in the field of radar for remote sensing technology. The potential application is for landcover, disaster monitoring, snow cover, and oceanography mapping.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.301-304
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• 2008

Since longer wavelength microwave radiation can penetrate clouds, satellite passive microwave sensors can observe sea ice of the entire polar region on a daily basis. Thus, it is becoming popular to derive sea ice motion vectors from a pair of satellite passive microwave sensor images observed at one or few day interval. Usually, the accuracies of derived vectors are validated by comparing with the position data of drifting buoys. However, the number of buoys for validation is always quite limited compared to a large number of vectors derived from satellite images. In this study, the sea ice motion vectors automatically derived from pairs of AMSR-E 89GHz images (IFOV = 3.5 ${\times}$ 5.9km) by an image-to-image cross correlation were validated by comparing with sea ice motion vectors manually derived from pairs of cloudless MODIS images (IFOV=250 ${\times}$ 250m). Since AMSR-E and MODIS are both on the same Aqua satellite of NASA, the observation time of both sensors are the same. The relative errors of AMSR-E vectors against MODIS vectors were calculated. The accuracy validation has been conducted for 5 scenes. If we accept relative error of less than 30% as correct vectors, 75% to 92% of AMSR-E vectors derived from one scene were correct. On the other hand, the percentage of correct sea ice vectors derived from a pair of SSM/I 85GHz images (IFOV = 15 ${\times}$ 13km) observed nearly simultaneously with one of the AMSR-E images was 46%. The difference of the accuracy between AMSR-E and SSM/I is reflecting the difference of IFOV. The accuracies of H and V polarization were different from scene to scene, which may reflect the difference of sea ice distributions and their snow cover of each scene.