• Atmosphere
• /
• v.34 no.2
• /
• pp.139-151
• /
• 2024

The Yeongdong region has suffered from severe snowstorms and the relevant damage such as traffic accidents on slippery roads, and the collapse of greenhouses and temporary buildings. While a lot of research on snowfall has been conducted, the detailed study of snow crystals' phase and habit through intensive observations and the relevant microphysical analysis is still lacking. Therefore, a snowflake camera, PARSIVEL, and intensive radiosonde soundings were utilized to investigate phase and habit changes in solid precipitation. Two remarkable episodes of phase and habit changes were selected such as 19 March 2022 and 15 February 2023. Both events occurred in the synoptic condition of the High in the north and the Low passing by the south, which was accompanied by rapid temperature cooling below 2.5 km. During the events of a short period between 3 to 6 hours, the temperature at 850 hPa decreased by about 4 to 6℃. This cooling led to a change in the main habit of snow particles from riming to aggregate, identified with both MASC and PARSIVEL. Meanwhile, the LDAPS model analyses do not successively represent the rapid cooling and short-term variations of solid precipitation, probably by virtue of overestimating low-level equivalent potential temperature during these periods. The underlying causes of these the low-level temperature variations within 6 hours, still remain unclear. It might be associated with mesoscale orographic phenomenon due to the mountains and East Sea effects, which certainly needs an intensive and comprehensive observation campaign.

• Korean Journal of Environmental Agriculture
• /
• v.34 no.1
• /
• pp.30-37
• /
• 2015

BACKGROUND: During the winter, the use of deicers was rapidly increased for reduction of traffic accidents as well as injuries in Korea, whose components are largely comprised of calcium chloride and sodium chloride. Recently, to reduce the adverse effects of chloride-deciers such as pollution of water and soil, and decrease of agricultural productivity, the attention of eco-friendly deciers have been increased. This study aimed to investigate biological effects of magnesium chloride deicer (PC-10) and organic acid deicer (EFD-1) against wheat, barley, and spinach. METHODS AND RESULTS: We examined the effect of two deciers, PC-10 and EFD-1 on the seed germination and growth of wheat, barley and spinach. EFD-1 showed higher suppression of the germination than PC-10 among tested crop seeds. In demage index of the seedlings of the crops, there was no symptoms in spinach such as spotting and color change of leaves. EFD-1 showed much stronger inhibitory effect on the germination of tested crop seeds than PC-10 when crops were exposed continuously to tested deciers in soils. The growth and shoot and root in examined crops was relatively higher in PC-10 treatment than in EFD-1 treatment when compared to the control. The biomass decrease was found in all examined conditions of deciers. PC-10 showed 23-35% reduction of biomass whereas EFD-1 exhibited 39-84% loss in all examined crops at over 2% concentration. CONCLUSION: These results suggest that the effects of deicers used in this study by inputting into soil against growing tested crops cause the reduction of germination of seeds, growth, and biomass compared to the control.

• The Journal of Korean Institute of Next Generation Computing
• /
• v.13 no.6
• /
• pp.7-20
• /
• 2017

The advancement of cloud and big data and the considerable growth of traffic have increased the complexity and problems in the management inefficiency of existing networks. The software-defined networking (SDN) environment has been developed to solve this problem. SDN enables us to control network equipment through programming by separating the transmission and control functions of the equipment. Accordingly, several studies have been conducted to improve the performance of SDN controllers, such as the method of connecting existing legacy equipment with SDN, the packet management method for efficient data communication, and the method of distributing controller load in a centralized architecture. However, there is insufficient research on the control of SDN in terms of the quality of network-using applications. To support the establishment and change of the routing paths that meet the required network service quality, we require a mechanism to identify network requirements based on a contract for application network service quality and to collect information about the current network status and identify the violations of network service quality. This study proposes a method of identifying the quality violations of network paths through ontology to ensure the network service quality of applications and provide efficient services in an SDN environment.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.1 no.1
• /
• pp.41-51
• /
• 2002

As Advanced Traveler Information System(ATIS) is the kernel of the Intelligent Transportation System, it is very important how to manage data from traffic information collectors on a road and have at borough grip of the travel time's change quickly and exactly for doing its part. Link travel time can be obtained by two method. One is measured by area detection systems and the other is estimated by point detection systems. Measured travel time by area detection systems has the limitation for real time information because it Is calculated by the probe which has already passed through the link. Estimated travel time by point detection systems is calculated by the data on the same time of each. section, this is, it use the characteristic of the various cars of each section to estimate travel time. For this reason, it has the difference with real travel time. In this study, Artificial Neural Networks is used for estimating link travel time concerned about the relationship with vehicle detector data and link travel time. The method of estimating link travel time are classified according to the kind of input data and the Absolute value of error between the estimated and the real are distributed within 5$\~$15minute over 90 percent with the result of testing the method using the vehicle detector data and AVI data of Namsan Tunnel $\#$1. It also reduces Time lag of the information offered time and draws late delay generation and dissolution.

• Journal of Korean Society of Transportation
• /
• v.36 no.3
• /
• pp.216-228
• /
• 2018

In this study analyzed the ponding changing of plastic deformation section follwed time development to apply weather, geometry and traffic data in additon to time development to improve road management service and safety of roads during or after rain. After We selected an 8.3km section of old national highway the Seongnam-Janghowon section and created a three-demensional surface of terrain through the numerical transformantion of design drawing data, with reflection the linear data of the same coordinate system in order to describe more realistic roads, we design additional structures with shading above roads. The altitude and azimuth of the sun were calculated and set based on the longitude and latitude data of the survey line for the analysis of the sun rate, and the daylight impact zone was visualized by setting the shaded time to an interval of 1 hour and the shade rate of the corresponding section. In addition, the evaporation volume calculated from weather data such as temperature, humidity, radiant energy, and road temperature analyzes together, it will use the way of a safer and more efficient road management as grasping the ponding changing more efficent in time development.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.9 no.1
• /
• pp.20-33
• /
• 2006

Changing of industry structure and development of traffic and telecommunications requires a change of the knowledge about the space where the human beings reside. Step by step the world is being divided into specified utility blocks. Today there is a limit that only one local government can compete with another region in the world. This study provides decision support tools with the use of GIS on the regional level for regions competition. GIS establishes regions and analyzes their geographic environment data, which will help in local-government problem solving and provide framework data for similar regions to become the community. The wide-area GIS application can present an objective and rational basis for regulation of inefficient investments and excessive competition between adjacent regions. The study area is Gangwon-do. Considering specific features of Gangwon-do which preserved high-quality environment resources, river basins were taken as a basis among natural regional elements. The main object of analysis conducted were the facts relevant to environmental regulation. The Gangwon-do consists of three regions in this study: Yongdong region, North-Hangang region and South-Hangang region. The analysis of each region regulation cases showed the following: in Youngdong region the forests regulation rate is high, in North-Hangang region the military installations protection sector's rate as well as regulation rate for water resources protection is relatively high, in South-Hangang region the forest and water resources regulation rate is high. The percentage of forests and water regulation rate appeared to be rather high in Gangwon-do, which means that the value of forest and water resources there is very high.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.42 no.6
• /
• pp.89-100
• /
• 2014

The Campus Core is centered at the physical, functional and symbolic environment of a university, which is known as the top academic institution, hence it metaphorically represents not only the educational philosophy when institution first opened, but also the transformed values of the time. Today, universities are asked to actively communicate with the local community in terms of function and be remodeled as pedestrian-friendly campuses in terms of physical environment. For this reason, the study comprehends the concept of the campus core in accordance with a pedestrian-friendly environment and suggests a practical plan for campus cores of district national universities based on previous research examination. Since the purpose of the study is to suggest a change in the circulation system centered on vehicle use to transform into a pedestrian-friendly environment through a planned approach while introducing public mixed-use at the same time, the study supports the fact that it is possible to reorganize the strategy of a pedestrian-friendly circulation system and partially revise the land utilization to yield the expected outcomes. Thus, this study will provide valid suggestions for similar maintenance plans while looking back to the meaning and value of today's campus core.

• Journal of Preventive Medicine and Public Health
• /
• v.27 no.2 s.46
• /
• pp.175-185
• /
• 1994

In order to anticipate disease pattern and health problems of Koreans in the 1st part of 21st century (by the year 2020), transition of population characteristics, mortality and morbidity data during the last 30 years Koreans have experienced were reviewed. On the actual basis of epidemiologic transition process that has undergone during last 30 years since 1960 along with socioeconomic development and successful implementation of selective national health policies (family planning, medical insurance and etc.), following changes can be expected in the 21st century in Korea, under the assumption that the current rate of progress is maintained. The population of South Korea alone will be doubled the population of 1960 by the year 2013 : aged Population older than 65 years will be increased from 3.3% in 1960 to 11.4% in 2020 with increased average age of the population from 23.6 year in 1970 to 39.2 year in 2020; urban population from 28% in 1960 to 83% in 2005. GNP/capita has increased tremendously from U.S. $120 in 1970 to $6,749 in 1992, and the government estimated it would be 519,350 in 2010 and $29,460 in 2020. Growth and developmental indices of children, educational achievement and social status of women also showed a remarkable improvement and anticipated to make futher progress. Leading causes of mortality and morbidity have shown a striking change during the last 30 years, from infectious diseases to chronic degenerative diseases and man-made injuries. Occurrence of communicable diseases may become minimal although viral hepatitis, venereal diseases Including AIDS, and well adapted herpes virus infections will maintain their endemic level. Newly evolving infectious agents, however, should be carefully monitored because of rapidly changing environments and human behaviours. Tuberculosis may increase up to the epidemic level when AIDS prevails. Ischemic heart diseases may increase steadily with increasing occurrence of hypertension and diabetes mellitus whereas cerebrovascular diseases may be decreased slowly. Musculaskeletal diseases which contribute a lot to the disability of aged people may be a major health problems due to increased aged population. Mental diseases, particularly that caused by alcohol and drug abuse, and senile dementia may become a prominent health problem. On the other hand injuries caused by traffic and industrial accidents that have shown most striking increase till now may be decreased considerably by intensive intervention. The health policies in the 21st century will be oriented to the health promotion for good quality life rather than life-savings.

• Proceedings of the KOR-BRONCHOESO Conference
• /
• 1982.05a
• /
• pp.8.2-8
• /
• 1982

Hoarseness is the change of voice quality which represents the abnormal function of phonation and is the main symtom of the laryngeal diseases. The etiology of hoarseness are known more than 50 causes, among them, viral upper respiratory infection is the main cause of hoarseness and the laryngeal nodule and polyp, laryngeal paralysis, laryngeal cancer, laryngeal papilloma and the laryngeal tuberculosis are the other causes of hoarseness in that order. Recently, the authors experienced 4 cases of uncommon etiology of hoarseness, so we present the cases with the brief review of literatures. Case 1. 29 years old male Admitted in Dept. of neurosurgery due to Traffic Accident. He had a trauma on the anterior neck. Hoarseness was developed on 1 month after the accident. Laryngoscopic finding; Paramedian paralysis of left vocal cord. Displacement of left arytenoid cartilage. Case 2. 53 years old male Admitted in Dept. of General Surgery due to Clonorchis Sinensis, under the general endotracheal anesthesia, Choledochostomy was performed. Laryngoscopic finding; Median paralysis of left vocal cord. Case 3. 56 years old male Admitted in Dept. of Internal Medicine due to Aortic Aneurysm. Hoarseness was developed on 3 months prior to admission. Laryngoscopic finding; Intermediated position paralysis of left vocal cord. Displacement of left arytenoid cartilage. Case 4. 74 years old male Admitted in Dept. of Internal Medicine due to Bronchogenic carcinoma. Hoarseness was developed on 3 years prior to admission. Laryngoscopic finding; Paramedian paralysis of right vocal cord.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.9 no.8
• /
• pp.939-944
• /
• 2014

Traffic accidents caused by the attention dispersion are increasing and the behavior of the attention dispersion affects the front-observing rate, road keeping ability, and reaction time for a dangerous situation. Many drivers listen to a radio broadcast and they have to change the frequency for continuously listening a radio broadcast of the specific broadcasting station in case of crossing a boundary of the particular area. In this situation, the possibility of a car accident increases, because the attention dispersion of a driver might be occurred. Especially, the risk of a car accident caused by changing the frequency of a radio is more serious in the highway, due to the high speed of a vehicle. In order to reduce the risk of a car accident caused by handling a radio during driving car, in this paper, we propose an automatic frequency conversion algorithm for vehicle radio, which saves normal system frequencies of primary broadcasting stations in a database and determines new frequency of the changed area using the location information obtained from a navigation system in a boundary of the specific area. After determining new frequency, the proposed algorithm selects a frequency with better receiving rate comparing signal-to-noise ratios (SNRs) of two signals corresponding previous and new frequencies.