• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.36 no.4
• /
• pp.366-369
• /
• 1991

This study was carried out to find out the properties of rice grain with embryo part. Obong-byeo. The embryo part on the rice remained by 96.7% in Obongbyeo after complete removal of the brans by common milling method. In nutritional composition. the content of lipid. vitamin B$_1$ and niacin were greater in Obongbyeo than Nagdongbyeo as a check variety. In particular. the contents of vitamin B$_1$ and niacin were about 1,5 times higher. Increased weight and feed effect of rat raising with milled rice were 107 and 172% in Obongbyeo and 101 and 125% in Nagdongbyeo. respectively. Eating quality of Obongbyeo was better than Nagdongbyeo.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.19 no.6
• /
• pp.208-221
• /
• 2020

The objective of this study is to estimate and analyze the traffic density of continuous flow using the trajectory of individual vehicles and the headway of sample probe vehicles-front vehicles obtained from ADAS (Advanced Driver Assitance System) installed in sample probe vehicles. In the past, traffic density of continuous traffic flow was mainly estimated by processing data such as traffic volume, speed, and share collected from Vehicle Detection System, or by counting the number of vehicles directly using video information such as CCTV. This method showed the limitation of spatial limitations in estimating traffic density, and low reliability of estimation in the event of traffic congestion. To overcome the limitations of prior research, In this study, individual vehicle trajectory data and vehicle headway information collected from ADAS are used to detect the space on the road and to estimate the spatiotemporal traffic density using the Generalized Density formula. As a result, an analysis of the accuracy of the traffic density estimates according to the sampling rate of ADAS vehicles showed that the expected sampling rate of 30% was approximately 90% consistent with the actual traffic density. This study contribute to efficient traffic operation management by estimating reliable traffic density in road situations where ADAS and autonomous vehicles are mixed.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.38 no.1
• /
• pp.29-39
• /
• 2018

In this study, the applicabilities of flood risk indices using FVI from IPCC, PSR method from OECD, and DPSIR method from EEA, were analyzed. Normalized values of daily maximum rainfall, hourly maximum rainfall, ten minute maximum rainfall, annual precipitation, total days of heavy rainfall (more than 80mm/day), density of population, density of asset, DEM, road statistics, river maintenance ratio, reservoir capacity, supply ratio of water supply and sewerage, and pumping capacity were constructed from 2000 to 2015 for nationwide 113 watersheds, to estimate flood risk indices. The estimated indices were compared to 4 different types of flood damage such as the number of casualties, damage area, the amount of flood damage, and flood frequency. The relationships between flood indices and different flood damage types demonstrated that the flood index using the PSR method shows better results for the amount of flood damage, the number of casualties and damage area, and the flood index using the DPSIR method shows better results for flood frequency.

• Journal of Korea Water Resources Association
• /
• v.51 no.spc
• /
• pp.1149-1159
• /
• 2018

This study aims to predict the future flood damage cost of 113 middle range watersheds using 26 GCM outputs, hourly maximum rainfall, 10-min maximum rainfall, number of days of 80 mm/day, daily rainfall maximum, annual rainfall amount, DEM, urbanization ratio, population density, asset density, road improvement ratio, river improvement ratio, drainage system improvement ratio, pumping capacity, detention basin capacity and previous flood damage costs. A constrained multiple linear regression model was used to construct the relationships between the flood damage cost and other variables. Future flood damage costs were estimated for different RCP scenarios such as 4.5 and 8.5. Results demonstrated that rainfall related factors such as annual rainfall amount, rainfall extremes etc. widely increase. It causes nationwide future flood damage cost increase. Especially the flood damage cost for Eastern part watersheds of Kangwondo and Namgang dam area may mainly increase.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.22 no.6
• /
• pp.92-101
• /
• 2023

The increasing use of personal mobility has led to a rise in traffic accidents and social issues. Consequently, the government is continually revising laws and regulations to address the problems associated with personal mobility. This study conducted a survey that reflects user characteristics and public perceptions based on the law revised in May 2021. The personal characteristics, legal awareness, usage patterns, risk characteristics, and risk factors were analyzed. The analysis indicated that driving on roads without separate sidewalks, speeding, and carrying passengers are hazardous practices. Moreover, Poor awareness of the legal framework governing personal mobility results in law violations. These results are significant as they highlight the need for policy measures regarding institutional and legal improvements, and they underscore the importance of enhancing social awareness about safety as personal mobility become more widespread.

• Korean Journal of Construction Engineering and Management
• /
• v.15 no.5
• /
• pp.31-39
• /
• 2014

It has been a long time since cars had become important means of transportation in human life. Since 1970s, cars have been increasing steadily because of rising individual income and changing lifestyle toward leisure and convenience. The number of cars is just 1.8 per thousand populations in 1970s, however, in 2012, it has increased to 291.15. Forecasting the demand for cars would be useful to plan, construction or management in the field of motor industry, road building and establishing facilities. Our study predicts the demand of cars through estimating the growth curve model. Especially, we include ageing variables to forecasting identifying the effect of ageing on the demand of cars. The main findings are as follows. In 2045, the number of cars is expected to reach 486.8 per thousand populations with passing a primary saturation point at early 2020s. Also, due to effect of ageing, the predicted demand of cars is about 10% lower than in case of which if ageing effect not exist.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.9
• /
• pp.133-140
• /
• 2016

The Ministry of Land, Infrastructure and Transport has introduced low-floor buses, which are convenient for passengers getting on and off the bus and for the handicapped. The standard bus model is 11 m long and uses compressed natural gas (CNG). However, this model has drawbacks in narrow rural road conditions such as those in farming and fishing villages and mountainous areas, as well as difficulty in refueling since CNG facilities are not readily available. In this study, running resistance values were obtained by coasting performance tests on actual roads using a Tata Daewoo LF-40 model with three different weight conditions: curb vehicle weight (CVW), half vehicle weight (HVW), and gross vehicle weight (GVW).The test methods include WHVC, NIER-06, and constant-speed driving at 60 km/h. These tests were used to measure the fuel economy of vehicles other than the target vehicles to obtain the combined fuel economy. The energy efficiency was highest in the case of CVW. In the WHVC mode, the fuel consumption rates of HVW and GVW were typically 3.5% and 12% higher than that of CVW, respectively. In constant-speed driving, the fuel efficiency of HVW was higher than that of CVW. Further research is required to analyze the exhaust gas data.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.23 no.5
• /
• pp.75-83
• /
• 2019

In order to fulfill the obligation to voluntarily reduce greenhouse gas emissions under the Paris Climate Agreement, the proportion of coal and nuclear power generation is reduced worldwide and national efforts are being made to spread renewable energy including solar power generation. Korea also intends to increase the proportion of renewable energy generation to 30~35% by 2040 by introducing laws and regulations. In addition, while the country is trying to apply solar power generation to sidewalks and roads, there is no research related to it in Korea. Therefore, as a precedent study to develop solar power generation roads, solar power generation concrete blocks applicable to sidewalks and plazas were developed and the applicability was evaluated by constructing them on the site. As a result of indoor experiment, compressive strength was measured by 25.5~35.7MPa and flexural strength was measured by 5.1~10.5MPa, which showed that all domestic standards were satisfied. However, the higher the unit cement amount, the lower the strength was measured according to the mixing of the broken fine aggregate. The absorption rate was 5.7%, which satisfied the domestic standard of 7% or less. As a result of the freeze-thawing test, the reduction rate of the compressive strength after 100 cycles was up to 6.3%. As a result of measuring the settlement amount after construction, the maximum of 2.498mm was measured and irregular settlement occurred in the overall area, which is because the resolution of the sand layer was poor during construction. Maintenance techniques of sidewalk concrete block and solar panel need to be established more efficiently through long-term operation in the further.

• Journal of Navigation and Port Research
• /
• v.36 no.6
• /
• pp.481-488
• /
• 2012

As an exploratory research to understand the nature of relationships between ports and their neighboring communities, this study analyzes how ports influence their residents' quality of life(QOL). The QOL was measured by 17 indicators reconstructed by reviewing relevant literatures. As a result, both Busan port and Dalian port were found to have statistically significant influence on many of QOL indicators including general expenditure per capita, number of manufacturing factories per capita, number of factories's laborer per capita, the rate of pavement, number of traffic accident per capita, rate of housing supply, number of financial agencies per capita, park area per capita, number of cultural assets per capita, the size of welfare expenditure per capita, number of fire occurrence per capita. And Busan port have statistically significant influence on QOL indicators including the rate of increase in population, number of public health industries per capita, number of public health industries per capita, number of schools per capita, number of sick-beds per capita, but Dalian port not have influence. Also Dalian port have statistically significant influence on number of crime occurrence per capita, but Busan port not have influence.

• Journal of Korean Society of Transportation
• /
• v.29 no.5
• /
• pp.121-138
• /
• 2011

More affordable and available cutting-edge technologies (e.g., wireless vehicle communication) are regarded as a possible alternative to the fixed infrastructure-based traffic information system requiring the expensive infrastructure investments and mostly implemented in the uninterrupted freeway network with limited spatial system expansion. This paper develops an advanced decentralized traveler information System (ATIS) using vehicle-to-vehicle (V2V) communication system whose performance (drivers' travel time savings) are enhanced by three complementary functions (autonomous automatic incident detection algorithm, reliable sample size function, and driver behavior model) and evaluates it in the typical $6{\times}6$ urban grid network with non-recurrent traffic state (traffic incident) with the varying key parameters (traffic flow, communication radio range, and penetration ratio), employing the off-the-shelf microscopic simulation model (VISSIM) under the ideal vehicle communication environment. Simulation outputs indicate that as the three key parameters are increased more participating vehicles are involved for traffic data propagation in the less communication groups at the faster data dissemination speed. Also, participating vehicles saved their travel time by dynamically updating the up-to-date traffic states and searching for the new route. Focusing on the travel time difference of (instant) re-routing vehicles, lower traffic flow cases saved more time than higher traffic flow ones. This is because a relatively small number of vehicles in 300vph case re-route during the most system-efficient time period (the early time of the traffic incident) but more vehicles in 514vph case re-route during less system-efficient time period, even after the incident is resolved. Also, normally re-routings on the network-entering links saved more travel time than any other places inside the network except the case where the direct effect of traffic incident triggers vehicle re-routings during the effective incident time period and the location and direction of the incident link determines the spatial distribution of re-routing vehicles.