• Korean Journal of Remote Sensing
• /
• v.19 no.3
• /
• pp.223-231
• /
• 2003

With the negative influences and damage from Asian dust increasing, it's getting important to investigate the climate and soil condition of the source region of Asian dust. There is a high possibility that the desertification and the drastic decrease of plants in China and Mongolia make worse the situation (bad effects of Asian Dust). To detect the movement of Asian dust caused by air circulation, we need to watch the state of the source region to get useful information for the prevention of the dust pollution, and to predict what part of China will become the source region. Therefore, using TOMS aerosol index data, NCEP reanalysis data that is Remote Sensing data from 1981 to 2000 (except 1993~1996, 4 years), for 16 years, examined the relation between the dust occurrence and weather elements. Dust occurrence appeared much in spring season from March to May in study areas. It had a dry climate during that season as follows : relative humidity about 20~40%, temperature about -5~5$^{\circ}C$, precipitation about 33-180 mm, wind speed about 4-10 ms-1. Dust occurrence and weather element annual change in study areas decreased gradually till 1990, but in Gobi desert the incidence of dust occurrence increased since 1997. As a result, found out that the more the precipitation, the less dust occurrence, because the precipitation and surface wind speed had a direct influence on the soil of the source region of dust.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.22 no.3
• /
• pp.125-132
• /
• 2022

The Ministry of Environment recently analyzed the output data of 10 fine dust measuring stations and, as a result, announced that about 60% had an error that the existing atmospheric measurement concentration was higher. In order to accurately predict fine dust, the wind direction and measurement position must be corrected. In this paper, in order to solve these problems, fuzzy rules are used to solve these problems. In addition, in order to calculate the fine particulate sensation index actually felt by pedestrians on the street, a computer simulation experiment was conducted to calculate the fine particulate sensation index in consideration of weather conditions, temperature conditions, humidity conditions, and wind conditions.

• Journal of People, Plants, and Environment
• /
• v.22 no.3
• /
• pp.309-319
• /
• 2019

This study was conducted to investigate the effects of watching a virtual reality (VR) forest video on stress reduction in adults. Experiments were performed in an artificial climate chamber where temperature, humidity and illumination were controlled. To cause stress in subjects, the subjects were asked to multiply two digit numbers by one digit numbers for two minutes. The subjects then watched a VR forest video for five minutes. During the experiment, the heart rate variability (HRV) and heart rate (HR) of subjects were continuously measured for evaluating their physiological state. After measuring the baseline and watching a VR forest video, their psychological state was evaluated using the profile of mood state (POMS), semantic differential (SD) method, and positive affect and negative affect schedule (PANAS). The results of physiological evaluation after watching a VR forest video showed a decrease in the stress index and HR, an increase in the activity of the parasympathetic nervous system, and the standard deviation of normal to normal RR intervals (SDNN). The results of psychological assessment confirmed that watching a VR forest video induced "comfort", "natural", and "soothed" feelings in subjects. In addition, watching a VR forest video decreased "tension-anxiety (T-A)", "depression-dejection (D)", "anger-hostility (A-H)", "fatigue (F)", "total mood disturbance (TMD)", and increased "vigor (V)" compared to the base line, and decreased "negative affect" and increased "positive affect." These results indicate that watching a VR forest video decreases adults' stress index, stabilizes physiological state, and has a positive impact on psychological state. The findings of this study can serve as a basis for providing forest welfare services to people in the blind spots of forest welfare, and can lay a foundation for the adoption of VR, one of the technologies of the fourth industrial revolution in forestry.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.46 no.3
• /
• pp.59-68
• /
• 2023

Currently, yellow phosphor of Y3Al5O12:Ce3+ (YAG:Ce) fluorescent material is applied to a 450~480nm blue LED light source to implement a white LED device and it has a simple structure, can obtain sufficient luminance, and is economical. However, in this method, in terms of spectrum analysis, it is difficult to mass-produce white LEDs having the same color coordinates due to color separation cause by the wide wavelength gap between blue and yellow band. There is a disadvantage that it is difficult to control optical properties such as color stability and color rendering. In addition, this method does not emit purple light in the range of 380 to 420nm, so it is white without purple color that can not implement the spectrum of the entire visible light spectrum as like sunlight. Because of this, it is difficult to implement a color rendering index(CRI) of 90 or higher, and natural light characteristics such as sunlight can not be expected. For this, need for a method of implementing sunlight with one LED by using a method of combining phosphors with one light source, rather than a method of combining red, blue, and yellow LEDs. Using this method, the characteristics of an artificial sunlight LED device with a spectrum similar to that of sunlight were demonstrated by implementing LED devices of various color temperatures with high color rendering by injecting phosphors into a 405nm deep blue LED light source. In order to find the spectrum closest to sunlight, different combinations of phosphors were repeatedly fabricated and tested. In addition, reliability and mass productivity were verified through temperature and humidity tests and ink penetration tests.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.18 no.6
• /
• pp.1049-1056
• /
• 2023

The height of the atmospheric boundary layer indicates the peak developed when turbulence is generated by mixing heat and water vapor, and is generally determined through thermodynamic methods. Wind profilers produce atmospheric information from the scattering of signals sent into the atmosphere. A method for making the spectrum of turbulent components, turbulent kinetic energy dissipation rate, and refractive index structure coefficient was presented to determine the atmospheric boundary layer depth. Compared with the vertical distribution characteristics of potential temperature and specific humidity based on radiosonde data, the determination method of the atmospheric boundary layer height from wind profiler output was evaluated as very useful.

• Journal of Plant Biotechnology
• /
• v.31 no.2
• /
• pp.133-138
• /
• 2004

Growth of M.9 (Malus domestica Bark. cv) and M.26 (Malus domestica Bark. cv) of dwarf apple rootstock, cultured on MS agar medium in a vessel with ventilating stopper (VS) and then in vivo rooting and acclimatization under combined-treatment by some materials with IBA, were investigated. Concentration of $CO_2$ and ethylene in the vessel with VS was lower then in the vessel with non-VS. Change of temperature and humidity in the vessel with VS was repeated by light condition. Stomatal pares of tissue in the vessel with VS were immediately closed after plantlets were exposed to room humidity but those in the vessel with non-VS were opened after 20 minutes exposure to room humidity. Leaf area and chloroplast index of tissue in the vessel with VS was higher then in the vessel with non-VS. In vivo rooting ratio and acclimatization ratio of M.9 and M.26 was highest in 300mg/L IBA＋3％ sucrose dip-treatment among other combined- treatments.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.15 no.1
• /
• pp.547-554
• /
• 2014

In this study, have researched 'a' index from three sound sources, effects on subject and finding optimal 'a' index, which can improve subject's stability, concentration and productivity. Check the health status of subjects who were selected 5 male and 5 female university students, and the period of this experiment was about two months. It were measured each subject's EEG, HRV and vibra image to analyze transition of stability, concentration, stress and heart beat. The results was measured in an environmental test room of temperature $25[^{\circ}C]$, the relative humidity 50 [%], illuminance 1,000 [lux] and air current speed 0.02[m/sec] with 'a' index of three sound sources which are a=1.106, a=1.749 and a=2.227. Results in a=1.106 compared to before exposure, relative $S{\alpha}$ wave, relative $L{\beta}$ wave and relative $M{\beta}$ wave have been revitalized, asymmetry index, stress and HRV have been decreased. Thus, to increase stability, concentration and productivity, also to decrease stress, changes in sound source of a=1.106 was found to be the most effective.

• Journal of Korea Spatial Information System Society
• /
• v.9 no.2
• /
• pp.93-107
• /
• 2007

In this paper, an adaptive range aggregation spatial index method is proposed for spatial range query in ubiquitous sensor networks. As the ubiquitous sensor networks are the new information-oriented paradigm, many energy efficient spatial range query methods in ubiquitous sensor networks environment are studied vigorously. In sensor networks, users can monitor environment scalar data such as temperature and humidity during user defined time and spatial ranges. In order to execute spatial range query efficiently, rectangle based index methods are proposed, such as SPIX. But they define the return path as the opposite of its query transmit path. However, the sensor nodes in queried ranges are closed to each other, they can't aggregate the sensed value in a queried range because their query transmission paths are different. As a result, the previous methods waste energy unnecessarily to aggregate sensing data out of the queried range. In this paper, an adaptive aggregation index method is proposed that can aggregate values in a user defined range adaptively by using its neighbor information. It is shown that sensor power is saved efficiently by using the proposed method over the performance evaluation.

• Korean Journal of Environmental Agriculture
• /
• v.8 no.1
• /
• pp.30-36
• /
• 1989

To determine irrigated water temperature under the rice plant canopy, micrometeorological elements air temperature, relative humidity, water temperature, solar radiation, and the rice leaf area index the rice plant canopywere measured. Water temperature under the canopy was also estimated from these data. The results are as follows ; 1. Maximum and minimum temperatures of water in the paddy field were higher about $1-2^{\circ}C$ than those of air temperature. 2. Mean water temperature under the canopy became lower than mean air temperature when the leaf area indices were greater than 4, because of decreased light penetration rates 3. Penetration amounts of net radiation under the canopy can be estimated by an exponential equation 4. Estimated water temperatures under the canopy by a combination method model was adaptable in Suweon, a plain area, but its accuracy was lower in Jinbu, an alpine area.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.15 no.3
• /
• pp.153-160
• /
• 2013

This study was conducted to investigate the effect of ecological factors affecting Pinus densiflora forest distribution associated with climate change in the future. Ecological niche is used as a method to quantify the position occupied in biological communities, space, influence and all ecological factors. Ecological niche breadth was analyzed on meteorological and growth factors of P. densiflora. Nine sites (i.e., Gangneung, Jeongseon, Pyeongchang, Hamyang, Bonghwa, Yeongyang, Uljin, Uiseong and Boseong) were selected to set $20m{\times}20m$ quadrat from September to October 2010. The height, DBH, clearlength, crown width and basal area were measured at each quadrat and used as growth factors. In addition, the measured values from the closest weather stations of each survey area of the maximum, mean and minimum temperature, humidity and precipitation were used as meteorological factors. The ecological niche breadth of the five meteorological factors except humidity was low. It is considered that precipitation could effect on the distribution of P. densiflora forest. In particular, maximum temperature showed low ecological niche breadth less than 0.4 in most of the survey areas. However, the ecological niche breadth of the five growth factors was high in all survey areas.