• Journal of the Korean Institute of Landscape Architecture
• /
• v.45 no.5
• /
• pp.105-112
• /
• 2017

In order to analyze the effect of street trees on human thermal sensation(thermal comfort) in summer, microclimatic data were measured and analyzed at sunny and shaded locations of two deciduous broadleaf and three broadleaf evergreen species of street trees. As a result, the mean differences by species in air temperature, relative humidity and wind speed were small: $0.2{\sim}1.5^{\circ}C$, 0.9~5.3% and $0.1{\sim}0.5 ms^{-1}$, respectively, but the mean difference in the mean radiant temperature was great, $27.1^{\circ}C$. In the results of physiological equivalent temperature(PET) and universal thermal climate index(UTCI), which are human thermal sensation(thermal comfort) indexes, the shaded locations by the trees showed mean reduction rates of 21.2~31.3% in the PET compared with the sunny location, which are equivalent to 1.5~2.5 levels of thermal perception. Also, 12.7~20.0% in the UTCI was reduced by the trees' shadows, which is equivalent to 1~1.5 levels of heat stress. In addition, although the broadleaf evergreen trees had 5% greater mean reduction in PET than that of the deciduous broadleaf trees, the Zelkova serrata that belonged to the deciduous broadleaf trees showed the equivalent thermal reduction effect as the broadleaf evergreen trees because of the high density of branches and leaves. Therefore, the mean radiant temperature and the density of the crown(branches and leaves) were the main influences in thermal modification by these street trees in summer.

• Journal of Korean Society of Transportation
• /
• v.31 no.5
• /
• pp.71-78
• /
• 2013

This paper investigated the influences of ramp traffic flow on the lane utilization for signalized intersection approaches which are adjacent to an off-ramp-street junction. The statistical test showed a correlation between lane utilization and the ramp traffic flow. As the ramp traffic flow increases, the left lanes are less utilized and the right lanes are more utilized. The lane utilization factors are calculated by applying traffic data collected from the Seoul Metropolitan area. The utilization factors are 1.113 for 2 lanes, 1.124 for 3 lanes, and 1.131 for 4 lanes. The lane utilization factors proposed in the paper show higher values than those in current Korea Highway Capacity Manual (KHCM) under the conditions that the number of lanes is 2 or 3. However, the lane utilization factor for 4 lanes in the paper shows lower value than in KHCM. The ramp traffic flow causes more utilization of the right lanes than at normal signalized intersections and the extent gets larger as the number of lanes decreases. Based on the results of the paper, the lane utilization factors at signalized intersection approaches should be revised and reasonable capacity should be recalculated if the signalized intersection is adjacent to an off-ramp-street junction.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2009.11a
• /
• pp.164-164
• /
• 2009

This paper had analyzed property of LED chip which has appropriate distribution and had designed modeling in order to experiment optical property of LED module through simulation. also throughout error value between street light and simulation data, precisive simulation could be inferred. as a consequent, transformation of optical property had henceforth verified the first value of module array.

• Proceedings of the IEEK Conference
• /
• 2001.06e
• /
• pp.147-150
• /
• 2001

This paver has presented the architecture and function of the traffic signal enforcement system to detect and capture a image of the violating car in the street intersection. Also in the paper, the algorithm and method of detecting the violation car have been presented and the microwave detection method has been explained. And then this paper has showed the operation software interface for system and presented the experiment data carried out in the field.

• Journal of Internet Computing and Services
• /
• v.17 no.3
• /
• pp.115-128
• /
• 2016

Recently, converging Big Data and IoT(Internet of Things)has become mainstream, and public sector is no exception. In particular, this combinationis applicable to crime prevention in Korea. Crime prevention has evolved from CPTED (Crime Prevention through Environmental Design) to ubiquitous crime prevention;however, such a physical engineering method has the limitation, for instance, unexpected exposureby CCTV installed on the street, and doesn't have the function that automatically alarms passengers who pass through a criminal zone.To overcome that, this paper offers a crime prevention method using Big Data from public organizations along with IoT. We expect this work will help construct an intelligent crime-prevention system to protect the weak in our society.

• Korean Journal of Remote Sensing
• /
• v.38 no.6_1
• /
• pp.1395-1406
• /
• 2022

This study investigated the effects of the urban forest and street trees on flow and temperature distribution in the Daegu National Debt Redemption Movement Memorial Park. For this, we implemented tree-drag and tree-cooling parameterization schemes in a computational fluid dynamics (CFD) model and validated the simulated wind speeds, wind directions, and air temperatures against the measured ones. We used the wind speeds, wind directions, air temperatures predicted by the local data assimilation and prediction system (LDAPS) as the inflow boundary conditions. To investigate the flow and thermal characteristics in the presence of trees in the target area, we conducted numerical experiments in the absence and presence of trees. In the absence of trees, strong winds and monotonous flows were formed inside the park, because there were no obstacles inducing friction. The temperature was inversely proportional to the wind speed. In the presence of trees, the wind speeds(temperatures) were reduced by more than 40 (5)% inside the park with a high planting density due to the tree drag (cooling) effect, and those also affected the wind speeds and temperatures outside the park. Even near the roadside, the wind speeds and temperatures were generally reduced by the trees, but the wind speeds and air temperatures increased partly due to the change in the flow pattern caused by tree drag.

• Journal of Korean Society of Forest Science
• /
• v.111 no.4
• /
• pp.502-510
• /
• 2022

In the national greenhouse gas inventory, a settlements category has never been included owing to the lack of activity data. Therefore, this study was conducted to obtain basic data for estimating biomass carbon storage in settlements. Nondestructive stem analysis with a laser dendrometer was performed on four major street tree species (Metasequoia glyptostroboides, Prunus armeniaca, Ginkgo biloba, and Acer buergerianum) in Wonju city, South Korea. Allometric equations of the aboveground volume were developed using five models, and allometric equations of crown area were developed with diameter at breast height (DBH) as an independent variable. The best performing allometric equations were aD²+bD+c for M.glyptostroboides and G. biloba, aD+bD² for P. armeniaca, and a+bD² for A. buergerianum. Regarding the allometric equations of crown area with DBH as an independent variable, G. biloba and A. buergerianum exhibited low coefficients of determination (R²), i.e., < 0.364, whereas M. glyptostroboides and P. armeniaca exhibited satisfactory R² values, i.e., > 0.767, probably due to different street tree management practices. The allometricequations in this study will support the carbon inventory of settlements and urban tree monitoring in management practices.

• Journal of Microbiology
• /
• v.40 no.1
• /
• pp.11-19
• /
• 2002

Mice immunized with equine herpesvirus type-1(EHV-1) L-particles skewed a significant increase (p<7.75) in serum antibody titers. Upon a booster dose four weeks lateral antibody titers increased significantly. Interestingly, immunization via intravenous or intramuscular route induced significantly higher (p<0.75) antibody titers. However, mice iummunized with UV-treated L-particles, visions or immunization via intranasal route induced lower antibody titers. Upon challenge inoculation with wildtype EHV-1, our data showed there was a poor correlation between antibody titers and protection against virus replication. Therefore, the role of cell-mediated immunity Inwards protection was investigated. As predicted, the strongest cell-mediated immunity, as measured by delayed-hypersensitivity test, was detected in mice immunized with live virus particles. The magnitude of cell-mediated immune response correlated with the efficacy of L-particles as immunizing agent. The highest efficacy, as indicated in mice immunized via intranasal routed was highly correlated with cell-mediated immunity. A similar phenomenon was also demonstrated in mice immunized intranasally with UV-treated L-particles. However, the degree of protection was reduced when mice immunized intravenously or intramuscularly with UV-treated L-particles. In conclusion, protection conferred in these animals was highly implicated by immune cells and the least by antibodies. The route of immunization and the nature of the antigen also contributed to the efficacy of L-particles as immunizing agent. In contrast to that of herpes simplex virus type 1, our data showed EHV-1 non-infectious L-particles are highly suitable for immunization of the host against EHV-1 disease.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.24 no.6
• /
• pp.83-88
• /
• 2010

In this paper, to propose a valid method solving a problem relevant to grounding from actual field data, the experimental results relevant to touch and step voltages and surface potential profiles measured around the real-sized and small-sized grounding electrode models were described. The ground surface potential profiles and dangerous voltages around the concrete pedestals employed in street facilities such as street lamps, traffic signal lamp and controllers as a case study were measured and discussed. The hemispherical cell with a diameter of 1,160[mm] was employed to simulate uniform soil. As a result, the results measured with the small-sized model were in reasonably agreement with the data obtained from the real-sized installation. It was found that the small-sized model test could be employed as a useful means evaluating the dangerous voltages around grounding electrodes installed at the inaccessible areas such as mountains, underground, underwater, and so on.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.42 no.5
• /
• pp.1038-1046
• /
• 2017

In this paper, we propose the design of LED Streetlight Platform with capabilities of weather monitoring and color temperature control. Several previous works are focused on the energy efficiency or data management of streetlight system, but no work has been done on the lighting performance, especially when natural phenomenon such as fog or haze appears on the street and obstructs the visibility of drivers and pedestrians. To solve such issue, we propose the use of two LED lamps with different correlated color temperature, which will be activated interchangeably according to the condition on the street. We also present the design of communication scheme between each devices in the system. Moreover, our experimental results show the LED Streetlight Platform can perform well and the data can be displayed properly at the website.