• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.1 s.114
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• pp.21-36
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• 2006

This study was undertaken to analyze the effects of pavement thermal properties and water retention characteristics on the surface temperature of the gray permeable cement concrete pavement during the summer. Following is a summary of major results. 1) The hourly surface temperature of pavement could be well predicted with a heat transfer model program that incorporated the input data of major meteorological variables including solar radiation, atmospheric temperature, dew point, wind velocity, cloudiness and the evaporation rate of the pavements predicted by the time domain reflectometry (TDR) method. 2) When the albedo was changed to 0.5 from an arbitrary starting condition of 0.3, holding other variables constant, the peak surface temperature of the pavement dropped by 11.5%. When heat capacity was changed to $2.5\;kJm^{-3}K^{-1}\;from\;1.5\;kJm^{-3}K^{-1}$, surface temperature dropped by 8.0%. When daily evaporation was changed to 1 mm from 2 mm, temperature dropped by 5.7%. When heat conductivity was changed to $2.5\;Wm^{-1}K^{-1}\;from\;1.5\;Wm^{-1}K^{-1}$, the peak surface temperature of the pavement fell by 1.2%. The peak pavement surface temperature under the arbitrary basic condition was $24.46^{\circ}C$ (12 a.m.). 3) It accordingly became evident that the pavement surface temperature can be most effectively lowered by using materials with a high albedo, a high heat capacity or a high evaporation at the pavement surface. The glare situation, however, is intensified by raising of the albedo, moreover if reflected light is absorbed into surrounding physical masses, it is changed into heat. It accordingly became evident that raising the heat capacity and the evaporative capacity may be the moot acceptable measures to improve the thermal characteristics of the pavement. 4) The sensitivity of the surface temperature to major meteorological variables was as follows. When the daily average temperature changed to $0^{\circ}C\;from\;15^{\circ}C$, holding all other variables constant, the peak surface temperature of the pavement decreased by 56.1 %. When the global solar radiation changed to $200\;Wm^{-2}\;from\;600\;Wm^{-2}$, the temperature of the pavement decreased by 23.4%. When the wind velocity changed to $8\;ms^{-1}\;from\;4\;ms^{-1}$, the temperature decreased by 1.4%. When the cloudiness level changed to 1.0 from 0.5, the peak surface temperature decreased by 0.7%. The peak pavement surface temperature under the arbitrary basic conditions was $24.46^{\circ}C$ (12 a.m.)

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.2
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• pp.493-500
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• 2011

Recently, there has been an increase in the number of disaster victims locally due to climate change and a variety of frequently occurring natural disasters. The damage caused by abrupt weather change in local area by typical weather forecasting techniques is very limited and difficult. Recently local area weather monitoring system using wireless sensor network technology has been very actively studied. Thus an IEEE 802.15.4-based weather field server to measure and monitor the local weather changes was designed and developed in this study. The proposed weather field server utilizes a wireless sensor node and weather sensors to collect weather information such as temperature, humidity, illumination, dew point, barometric pressure, and water level. The integrated weather sensor board was designed to respond quickly to weather changes, and provide feedback to the server PC. Each weather information is analyzed in the server PC to establish a program to monitor and analyze the local area or the area of abrupt climate change in order to provide warning signals in case of disaster events in local.

• Journal of Korean Society of Transportation
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• v.16 no.2
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• pp.157-167
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• 1998

건설된 도로를 효율적으로 이용하고, 통행자의 편리성을 향상시키기 위해 첨단 여행자 정보체계(ATIS)를 활용할 수 있다. ATIS 체계하에서 노선정보를 통행자에게 제공하기 위해서는 교차로에서의 회전으로 인한 지체를 정확하게 반영할 수 있는 효율적인 최단경로 알고리즘이 필요하다. 하지만 기존의 최단경로탐색 알고리즘은 좌회전 금지, U-turn, P-turn 등 교차로에서의 회전으로 인한 지체를 정확히 반영 못한다는 단점을 갖고 있다. 그러므로 본 논문에서는 이러한 단점을 극복하기 위해 수정형 덩굴망 알고리즘을 재발하였다. 수정형 덩굴망 알고리즘은 노드표지(node labelling) 방법에 있어서는 기존의 덩굴망 알고리즘의 노드표지 방법과 개념적으로 동일하여 이용상의 편리성을 갖도록 하였으며, 최단경로 탐색기능에 있어서는 링크탐색알고리즘(혹은 링크표지기법)이 갖고 있는 장잠을 다 반영할 수 있는 기법으로 개발하였다. 수정형 덩굴망 알고리즘은 노드표지에 있어 특정 노드로 유입하는 방향에 따라 노드표지를 별도로 기록하였다. 따라서 교차로에서의 좌회전, 우회전 및 직진은 물론 U-turn의 경우에도 추가적인 절차 없이 현실적인 최단 경로를 탐색할 수 있도록 하였다. 또한 본 논문은 최단경로의 역추적 방법을 개선하여 좌회전 금지, U-turn, P-turn 및 기타 회전에 의한 지체등을 각 교차로마다 정확히 반영함으로써 비합리적인 최단경로가 추적되는 것을 근본적으로 차단하도록 하였다. 따라서 본 연구에서 개발한 수정형 덩굴망 최단경로탐색 알고리즘은 교차로에서의 회전지체 및 회전금지를 현실적으로 잘 반영함으로써 정확한 노선정보를 요구하는 ATIS체계를 분석하는데 유용하게 활용될 수 있는 기법이다.장자료를 통해 구하기란 현실적으로 불가능하므로, 본 연구에서는 이러한 제약점을 극복할 수 있는 근사적인 지체시간을 계산하는 방법을 제시한 점에서 의미를 갖을 수 있다.수들은 직업의 선택이나 소득을 예측하기 위한 요소들로 포함될 수 없었다. 따라서 후속연구에서는 이를 보완해야 할 것이며, 최근 들어 우리 나라에서도 재택근무에 대한 관심이 대두되고 있으나 아직 개념정의나 그 중요성과 가치, 그리고 실태 파악과 같은 연구가 활발히 이루어지지 못하고 있으므로 이에 대한 심층적인 연구가 행해져야 할 것이다.d similar flower proceeding dates in all branches. but "Daepung" showed similar flower proceeding dates in all branches.est in HB. Mean period of wetting duration was in the order of DS＞HB＞MB, while the dew point depression was greatest in DS.ANCOVA, Pearson correlation을 이용하여 분석하였으며, 그 결과는 다음과 같다. 캠프 프로그램은 소아 당뇨병 환자의 자기 효능을 증진시키고 환자 역할 행위 이행을 높여주는데 효과적 이었다. 소아 당뇨병 환자의 자기 효능은 환자 역할 행위 이행과 순 상관 관계가 있어, 자기 효능이 증진될수록 환자 역할 행위 이행 정도가 높아졌다. 무조건 사주지 않는다(8.0%), 무조건 사준다(3.1%)로 식품광고에 나오는 식품 요구시 부모의 70.3%가 거절하는 것으로 나타났다. 거절 이유는 건강에 나쁘다는 것이 가장 큰 이유였으며 강남과 강북 어린이간에 유의적인 차이가 있었다

• Journal of Korea Water Resources Association
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• v.39 no.1 s.162
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• pp.79-88
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• 2006

An accurate prediction of inflow water temperature is essentially required for real-time simulation and analysis of rainfall-induced turbidity 烈os in a reservoir. In this study, water temperature data were collected at every hour during the flood season of 2004 at the upstream of Daecheong Reservoir to justify its characteristics during rainfall event and model development. A significant drop of river water temperature by 5 to $10^{\circ}C$ was observed during rainfall events, and resulted in the development of density flow regimes in the reservoir by elevating the inflow density by 1.2 to 2.6 kg/$m^3$ Two types of statistical river water temperature models, a logistic model(DLG) and regression models(DMR-1, DMR-2, DMR-3) were developed using the field data. All models are shown to reasonably replicate the effect of rainfall events on the water temperature drop, but the regression models that include average daily air temperature, dew point temperature, and river flow as independent variables showed better predictive performance than DLG model that uses a logistic function to determine the air to water relation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.206-211
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• 2016

Various applications require dry air at low temperature, such automation equipment, semiconductor manufacturing, chemical production lines, and coating processes for the shipbuilding industry. Four evaporators for low temperature (below $0^{\circ}C$) were installed for a dehumidification system. Moist air is cooled sequentially over three evaporators. The first evaporator has an evaporation temperature of $13^{\circ}C$, that of the second evaporator is $5^{\circ}C$, and that of the third evaporator is maintained at $-1.3^{\circ}C$. In the fourth evaporator implantation thereby the moisture contained in the moisture air. A pressure regulator (CPCE 12) is used at this point and is defrosted when the vapor pressure is below a set value. The non-implantation moisture of the air is a heating system that uses the waste heat of a condenser with high temperature. It develops the cooling type's dehumidifier, which is important equipment that prevents the destruction of protein and measures the temperature and humidity at each interval by changing the front air velocity from 1.0 m/s to 4.0 m/s. The cooling capacity was also calculated. The greatest cooling capacity was 1.77 kcal/h for a front air velocity of 2.0 m/s

• Asian Journal of Turfgrass Science
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• v.20 no.2
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• pp.175-190
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• 2006

The term mycoherbicide started in 1970, but its interest heightened due to increase costs of chemical herbicides. A classical biocontrol agent is expected to become a permanent part of its new environment and do no harm to it. Contemporary biological control agent(BCA) must be produced by artificial culture and could be applied like chemical herbicides over weeds. BCA is different from the classical approach in that it released through natural spread. To date 26 species of fungi are used as classical BCA against 26 species of weeds in seven countries. There are a number of examples of pathogens attacking non-target plants. But through risk assessments which include understanding the taxonomy, biology and ecology, the target and non-target species, it will be safe to introduce of exotic pathogens to control weeds. But pathogens have not been successfully used in practice. Many mycoherbicides show potential in laboratories, but are ineffective in the field and not consistent from year to year or field to field. There is also a lack of understanding humidity, dew formation and temperature and their effects on suppression of weeds by plant pathogens. Potential pathogen must be selected as a BCA. Previous studies suggest that these pathogens must (1) produce abundant and durable inoculum in artifical culture, (2) be genetically stable and weed specific and (3) kill weeds in control. A granular preparation of mycoherbicide into sodium alginate is lighter than liquids and less bulky than organic matter. Gel forms have also been used.

• Journal of Conservation Science
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• v.35 no.2
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• pp.99-115
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• 2019

The Royal Tombs at Songsanri is one of the most important historic site for ancient historical study in Korean Peninsula. Since the excavation of the tombs, continuous exposure to the outside environment and the negative effects of the artificial air conditioning system have caused significant threats to the thermal environment stability of the tombs. Unlike the outside temperature that shows significant differences according to seasonal changes, the burial chamber of the tombs had a relatively stable temperature range of 11.4 to $22.2^{\circ}C$ throughout the year, and the standard deviation of temperature was within 3.5. It was revealed that major factors affecting the microclimate of the tombs were inflow of outdoor air, wind direction and speed, and all of them had closely related to airtightness of the tombs. The solar radiation was in inverse proportion to the thickness of burial mounds, and thus Royal Tomb of King Muryeong, which has the thickest burial mound, was least affected by solar radiation. Especially, microclimate of the tombs caused to the highest influence with artificial environmental changes due to access by people, which varied in proportion to the number of accessed people and time of stay. Currently, the inside of the tombs are sealed and always in saturated condition, it is very vulnerable to dew condensation. As a result of analyzing the possibility of condensation in each tomb, all the tomb No. 5, tomb No. 6 and Royal Tomb of King Muryeong had condensation most of the time throughout the year. It is required to make a proper conservation environment for the Royal Tombs at Songsanri.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.4
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• pp.305-317
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• 2022

To investigate the blossom infection risk of fire blight on pears, the program Maryblyt has been executed from 2018 to 2022 based on meteorological data from central-Korean cities where fire blight has occurred as well as from southern Korean cities where the disease has not yet occurred. In the past five years, years with the highest risk of pear blossom blight were 2022 and 2019. To identify the optimal time for spraying, we studied the spray mode according to the Maryblyt model and recommend spraying streptomycin on the day after a "High" warning and then one day before forecasted precipitation during the blossom period. Maryblyt also recommends to initiate surgical controls from mid-May for canker blight symptoms on pear trees owing to over-wintering canker in Korea. Web-cam pictures from pear orchards at Cheonan, Icheon, Sangju, and Naju during the flowering period of pear trees were used for comparing real data and constructing a phenological model. The actual starting dates of flowering at southern cities such as Sangju and Naju were consistently earlier than those calculated by the model. It is thus necessary to improve the forecasting model to include field risks by recording the actual flowering period and the first day of the fire blight symptoms, according to the farmers, as well as mist or dew-fall, which are not easily identifiable from meteorological records.

• Proceedings of the KSEEG Conference
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• 2001.05b
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• pp.42-63
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• 2001

The detail survey on the Songsanri tomb site including the Muryong royal tomb was carried out during the period from May 1 , 1996 to April 30, 1997. A quantitative analysis was tried to find changes of tomb itself since the excavation. Main subjects of the survey are to find out the cause of infiltration of rain water and groundwater into the tomb and the tomb site, monitoring of the movement of tomb structure and safety, removal method of the algae inside the tomb, and air controlling system to solve high humidity condition and dew inside the tomb. For these purposes, detail survery inside and outside the tombs using a electronic distance meter and small airplane, monitoring of temperature and humidity, geophysical exploration including electrical resistivity, geomagnetic, gravity and georadar methods, drilling, measurement of physical and chemical properties of drill core and measurement of groundwater permeability were conducted. We found that the center of the subsurface tomb and the center of soil mound on ground are different 4.5 meter and 5 meter for the 5th tomb and 7th tomb, respectively. The fact has caused unequal stress on the tomb structure. In the 7th tomb (the Muryong royal tomb), 435 bricks were broken out of 6025 bricks in 1972, but 1072 bricks are broken in 1996. The break rate has been increased about 250% for just 24 years. The break rate increased about 290% in the 6th tomb. The situation in 1996 is the result for just 24 years while the situation in 1972 was the result for about 1450 years. Status of breaking of bircks represents that a severe problem is undergoing. The eastern wall of the Muryong royal tomb is moving toward inside the tomb with the rate of 2.95 mm/myr in rainy season and 1.52 mm/myr in dry season. The frontal wall shows biggest movement in the 7th tomb having a rate of 2.05 mm/myr toward the passage way. The 6th tomb shows biggest movement among the three tombs having the rate of 7.44mm/myr and 3.61mm/myr toward east for the high break rate of bricks in the 6th tomb. Georadar section of the shallow soil layer represents several faults in the top soil layer of the 5th tomb and 7th tomb. Raninwater flew through faults tnto the tomb and nearby ground and high water content in nearby ground resulted in low resistance and high humidity inside tombs. High humidity inside tomb made a good condition for algae living with high temperature and moderate light source. The 6th tomb is most severe situation and the 7th tomb is the second in terms of algae living. Artificial change of the tomb environment since the excavation, infiltration of rain water and groundwater into the tombsite and bad drainage system had resulted in dangerous status for the tomb structure. Main cause for many problems including breaking of bricks, movement of tomb walls and algae living is infiltration of rainwater and groundwater into the tomb site. Therefore, protection of the tomb site from high water content should be carried out at first. Waterproofing method includes a cover system over the tomvsith using geotextile, clay layer and geomembrane and a deep trench which is 2 meter down to the base of the 5th tomb at the north of the tomv site. Decrease and balancing of soil weight above the tomb are also needed for the sfety of tomb structures. For the algae living inside tombs, we recommend to spray K101 which developed in this study on the surface of wall and then, exposure to ultraviolet light sources for 24 hours. Air controlling system should be changed to a constant temperature and humidity system for the 6th tomb and the 7th tomb. It seems to much better to place the system at frontal room and to ciculate cold air inside tombs to solve dew problem. Above mentioned preservation methods are suggested to give least changes to tomb site and to solve the most fundmental problems. Repairing should be planned in order and some special cares are needed for the safety of tombs in reparing work. Finally, a monitoring system measuring tilting of tomb walls, water content, groundwater level, temperature and humidity is required to monitor and to evaluate the repairing work.

• Research in Plant Disease
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• v.22 no.2
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• pp.72-80
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• 2016

Gummy stem blight, caused by the fungus Didymella bryoniae, is major disease of watermelons worldwide. The objective of the present study was to establish an efficient screening system to identify watermelon resistant to D. bryoniae. An GSB3 isolate was prepared from a watermelon plant showing typical symptoms of gummy stem blight in Haman-gun and identified as D. bryoniae based on molecular analysis of internal transcribed spacer sequence. A simple mass-production technique of inoculum was developed based on spore production of D. bryoniae GSB3 under several incubation conditions and their virulence on watermelon plants. Resistance degrees of 22 commercial watermelon cultivars to the GSB3 isolate were evaluated. Among them, four watermelon cultivars showing different degree of resistance response were selected for further study. Development of disease on the cultivars according to various conditions including inoculum concentrations, incubation periods in dew chamber, and incubation temperatures was investigated. From the results, we suggest an efficient screening method for resistant watermelon cultivars to gummy stem blight. Seeds of watermelon cultivar are sown and grown in a greenhouse until plant stage of 2-fully expanded leaves. Seedlings are inoculated with D. bryoniae by spraying spore suspension of the fungus at a concentration of $5.0{\times}10^5spores/ml$. The infected plants are incubated in humidity chamber at $25^{\circ}C$ for 48 hours and then transferred to a growth chamber at $25^{\circ}C$ and 80% relative humidity with 12-hour light a day. Three to four days after inoculation, disease severity of the plant are measured using percentage of infected leaf area.