• Journal of the Institute of Electronics and Information Engineers
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• 제54권4호
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• pp.99-107
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• 2017

This paper proposes a battery model coefficient correction method for improving the accuracy of existing lithium battery equivalent models. BMS(battery management system) has been researched and developed to minimize shortening of battery life by keeping SOC(state of charge) and state of charge of lithium battery used in various industrial fields such as EV. However, the cell balancing operation based on the battery cell voltage can not follow the SOC change due to the internal resistance and the capacitor. Various battery equivalent models have been studied for estimation of battery SOC according to the internal resistance of the battery and capacitors. However, it is difficult to apply the same to all the batteries, and it tis difficult to estimate the battery state in the transient state. The existing battery electrical equivalent model study simulates charging and discharging dynamic characteristics of one kind of battery with error rate of 5~10% and it is not suitable to apply to actual battery having different electric characteristics. Therefore, this paper proposes a battery model coefficient correction algorithm that is suitable for real battery operating environments with different models and capacities, and can simulate dynamic characteristics with an error rate of less than 5%. To verify proposed battery model coefficient calibration method, a lithium battery of 3.7V rated voltage, 280 mAh, 1600 mAh capacity used, and a two stage RC tank model was used as an electrical equivalent model of a lithium battery. The battery charge/discharge test and model verification were performed using four C-rate of 0.25C, 0.5C, 0.75C, and 1C. The proposed battery model coefficient correction algorithm was applied to two battery models, The error rate of the discharge characteristics and the transient state characteristics is 2.13% at the maximum.

• Journal of the Institute of Electronics and Information Engineers
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• 제54권1호
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• pp.96-110
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• 2017

Most of vehicle detection studies using the existing general lens or wide-angle lens have a blind spot in the rear detection situation, the image is vulnerable to noise and a variety of external environments. In this paper, we propose a method that is detection in harsh external environment with noise, blind spots, etc. First, using a fish-eye lens will help minimize blind spots compared to the wide-angle lens. When angle of the lens is growing because nonlinear radial distortion also increase, calibration was used after initializing and optimizing the distortion constant in order to ensure accuracy. In addition, the original image was analyzed along with calibration to remove fog and calibrate brightness and thereby enable detection even when visibility is obstructed due to light and dark adaptations from foggy situations or sudden changes in illumination. Fog removal generally takes a considerably significant amount of time to calculate. Thus in order to reduce the calculation time, remove the fog used the major fog removal algorithm Dark Channel Prior. While Gamma Correction was used to calibrate brightness, a brightness and contrast evaluation was conducted on the image in order to determine the Gamma Value needed for correction. The evaluation used only a part instead of the entirety of the image in order to reduce the time allotted to calculation. When the brightness and contrast values were calculated, those values were used to decided Gamma value and to correct the entire image. The brightness correction and fog removal were processed in parallel, and the images were registered as a single image to minimize the calculation time needed for all the processes. Then the feature extraction method HOG was used to detect the vehicle in the corrected image. As a result, it took 0.064 seconds per frame to detect the vehicle using image correction as proposed herein, which showed a 7.5% improvement in detection rate compared to the existing vehicle detection method.

• Economic and Environmental Geology
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• 제49권6호
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• pp.459-467
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• 2016

Due to the limited areal space for installation, borehole heat exchangers (BHEs) at depths deeper than 300 m are considered for geothermal heating and cooling in the urban area. The deep vertical closed-loop BHEs are unconventional due to the depth and the range of the typical installation depth is between 100 and 200 m in Korea. The BHE in the study consists of 50A (outer diameter 50 mm, SDR 11) PE U-tube pipe in a 150 mm diameter borehole with the depth of 300 m. In order to compensate the buoyancy caused by the low density of PE pipe ($0.94{\sim}0.96g/cm^3$) in the borehole filled with ground water, 10 weight band sets (4.6 kg/set) were attached to the bottom of U-tube. A thermal response test (TRT) and fundamental basic surveys on the thermophysical characteristics of the ground were conducted. Ground temperature measures around $15^{\circ}C$ from the surface to 100 m, and the geothermal gradient represents $1.9^{\circ}C/100m$ below 100 m. The TRT was conducted for 48 hours with 17.5 kW heat injection, 28.65 l/min at a circulation fluid flow rate indicates an average temperature difference $8.9^{\circ}C$ between inlet and outlet circulation fluid. The estimated thermophysical parameters are 3.0 W/mk of ground thermal conductivity and 0.104 mk/W of borehole thermal resistance. In the stepwise evaluation of TRT, the ground thermal conductivity was calculated at the standard deviation of 0.16 after the initial 13 hours. The sensitivity analysis on the borehole thermal resistance was also conducted with respect to the PE pipe diameter and the thermal conductivity of backfill material. The borehole thermal resistivity slightly decreased with the increase of the two parameters.

• Journal of the Korean Institute of Landscape Architecture
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• 제43권5호
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• pp.65-73
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• 2015

The purpose of this study was to compare the Mean Radiant Temperature(MRT) under two landscaping shade membranes, white and black, with those of natural outdoor spaces at summer midday. An additional perforated black shading net was applied and compared for the consideration of the practical application. The average MRT at the height of 2.4m, 10cm below the membranes of black, white, and perforated black were $49.1^{\circ}C$, $41.6^{\circ}C$ and $36.8^{\circ}C$ respectively, while that of open sky was $41.8^{\circ}C$. This indicates that a closer position to the darker membrane caused a higher MRT. At the height of 1.1m and 1.7m, the difference of MRT between the black and the white membranes was slight, while the value of white was unexpectedly higher than the black. The MRT of black perforated net showed the lowest value at every height. The black membrane absorbed more solar radiation than the white, which caused the greater release of long wave radiation and higher temperature near the membrane itself. In spite of the higher albedo of the white membrane, the higher solar radiation transmittance rate of which seemed to cause the slightly higher MRT than the black at the hight of 1.1m and 1.7m. In summary, the performance of the black membrane was slightly better than the white in terms of the air conditioning of the human related space around the height of 1.1m and 1.7m, when the shading membranes were at 2.5m height.

• Journal of the Korean Institute of Landscape Architecture
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• 제43권5호
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• pp.121-131
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• 2015

Village-concentrated agricultural regional development projects that aim for increased profits are now being aimed at core agricultural and fishing areas. These agricultural and fishing stimulus projects aim to not only increase the net profit of local citizens but also improve their living conditions. As the industry itself has changed, local rural areas have also changed in various ways. One such aspect is the emergence of rural-urban complexes known as "rurban" areas. These naturally occurring rurban regions are created by a combination of complex urban infrastructure while maintaining the insulated rural communities that agricultural areas are usually so readily identified by. "Jeongeupsi Naejangsnagdong", the target of this research, also specifies the unaltered surrounding natural environment of rural areas while at the same time containing complex central living areas typically found in urban areas. This research suggests that the direction of residents' participation in community-level rurban projects could solve the problems found in existing top-down government development projects. This research also suggests rurban area activation plans to improve living conditions through analysis of both local rurban agricultural characteristics and citizen demands. In order to encourage citizen autonomy and self-governing attitudes, citizen-strengthening workshop programs are proposed, such as citizen workshops or pilot activities. This research was carried out by target area analysis, rudimentary planning, development direction setting, detailed project planning, and finally project processing. This procedure established three goals, which are walking environment improvement, community infrastructure establishment, and good living environment establishments, based on actual site research and citizen demands. This research suggests plans to activate community groups that were already established and reflect citizen needs as the main avenues for local businesses. This research is predicted to promote more active and successful growth through autonomy in stimulating these increasingly emerging rurban agricultural regions.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제17권6호
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• pp.347-359
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• 2016

People are destined to live according to the time and fate after they are born. Man is connected with the idea that is called the Chinese zodiac sign related to one out of 12 animals, regardless of one's thought. This paper was written with the expectation that it will be a new turning point understanding the mutual influence and its changing process by catching the ethnic belief and emotion as well as its cultural background in the Asian Zone by investigating the meaning of the 12 Chinese zodiac shown in the folk painting from the viewpoint of folk lore including "Chinese zodiac sign" culture rooted in our daily lives. The animal 'Rat' has been lived well human beings accompanied by the fable or the nature, while the animal 'Ox' has been living together with human history. The 'Tiger' has been considered the 'Power retreating disease or a devil' to humans, which is the most frightening but near at hand. The 'Rabbit' in the fable is inculcating hope and ideals to humans. The imaginary 'Dragon' is rooted in the deep national belief, which is seated as 'Guardian god' of farming culture and mankind, while the 'Snake' is playing a role in protecting humans as the 'Sea God' in Tsushima and Jeju Island, and has been believed and followed in the deep mind of humans. The 'Horse' in the nomad culture has been adorned as the basic creature of nomadic society in the character of a psychic medium between the human and god or their 'Guardian god'. The ancient Japanese regarded 'Monkey' as holy, being connected with treasure. It infers a human's desire to borrow wisdom from 'Monkey'. 'Chicken' includes the meaning of a lucky sign connecting the sky and the human world by arranging together with humans. The 'Dog' is believed and followed as performing the function of a messenger connecting this world with the afterlife in the next world tale of shamanism. The 'Pig' also lives well with humans, being interpreted as fecundity. Although the meaning of the 12 Chinese Zodiac animals has ethnic differences, all of them have been shared with humans, rooted in the human mind, being believed, and followed in human lives.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제17권6호
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• pp.81-88
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• 2016

This research investigated the sensory processing ability and selected subjects who had sensory processing problems, and divided the subjects into an experimental group and control group. The experimental group was educated with sensory processing intervention on the activities of daily living to determine its influence on the quality of life. The study was based on 230 university students with similar majors in 3 universities of Chungcheong area in the beginning of May, 2013. From here, 32 subjects who had issues with their sensory processing ability were selected. The 230 students were given a survey on the quality of life, individual characteristics, and sensory processing ability. Later, the 32 subjects who had problems with their sensory processing ability were divided into an experimental group and control group. The control group performed sensory processing intervention, whereas the control group did not. After the sensory processing intervention method for 6 weeks, the quality of life was re-evaluated. As a result, the total score of the quality of life after intervention was 98.69 in the experimental group and 84.81 in the control group (p=0.001). The physical score was 16.43 in the experimental group and 14.64 in the control group (p=0.008). The psychological score was 14.71 in the experimental group and 11.75 in the control group (p<0.001). The social score was 14.67 in the experimental group and 13.17 in the control group (p=0.032). The environment score was 14.66 in the experimental group and 12.34 in the control group (p=0.006). The experimental group showed a significant increase in all areas of the quality of life, whereas the control group did not. Through this result, it can be seen that a sensory processing intervention method in daily life can increase the quality of life for subjects with problems in sensory processing ability. Overall, it will be necessary to apply a treatment of various sensory intervention programs for adults and promote a better quality of life.

• Journal of The Korean Society of Grassland and Forage Science
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• 제38권2호
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• pp.84-90
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• 2018

Cultivation of high-quality forage crop by using fallow field during winter is required for national high feed self-sufficiency and establishment of self-supply system of high-quality forage crop. Field experiments for cultivation of high-quality winter forage crop were conducted at the paddy and upland fields in Cheonan and Anseong city with treatments of single Italian ryegrass(IRG) and IRG mixed with forage barley at the paddy field and of single forage barley and forage barley mixed with IRG at the upland field in the Mid-west plain. Several cultivation conditions such as broadcasting IRG seed under standing rice, sowing time, tillage method, drainage condition, mixed sowing with forage barley were compared to know the change of growth, yield and quality of winter forage crop. In particular, over-wintering rate and dry matter yield were decreased significantly in late-sown IRG and moisture-stressed forage barley. Yield and quality of forage crops were increased by sowing after tillage, mixed sowing of IRG with barley at the paddy field with good drainage. High yield as much as dry matter $10MT\;ha^{-1}$ with high feed value could be obtained by early sowing of feed barley mixed with IRG at the upland field. Cultivation conditions such as early sowing, sowing after tillage, drainage management are required for higher dry matter yield, quality and stable cultivation of winter forage crops in the mid-west plain of Korea.

• Korean Journal of Environment and Ecology
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• 제34권1호
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• pp.1-8
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• 2020

This study conducted a full survey of the goral population using sensor cameras to identify the exact habitat of the gorals that inhabit Odaesan National Park and for restoration and habitat management-focused conservation projects following the population growth. We surveyed Odaesan National Park for a year in 2018 and selected18 grids (2km×2km) first based on the survey results. We then further divided each grid into four small grids (1km×1km) and installed a total of 62 sensor cameras in 38 small girds divided by four grids(1km×1km). The survey resulted in a total of 5,096 photographed wild animals, 2,268 of which were gorals, and the analysis by the classification table of goral (horn shape (Ⓐ), ring pattern (Ⓑ), ring formation ratio (Ⓒ), and facial color (Ⓓ)) identified a total of 95 animals. The ratio of male and female was 35 males (36.8%), 46 females (48.4%), and 14 sex unknowns (14.7%), while the ratio of female and male excluding sex unknowns was 4 (male):6 (female). The horn shape (Ⓐ) and face color (Ⓓ) were the important factors for distinguishing male and female and identifying individuals. The analysis of the correlation of 81 individuals, excluding 14 individuals of unknown sex, showed a significant difference (r=-0.635, p<0.01). Since the goral population in Odaesan National Park has reached a minimum viable population, it is necessary to change the focus of the management policy of Odaesan National Park from restoration to conservation.

• Korean Journal of Environment and Ecology
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• 제34권1호
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• pp.18-26
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• 2020

Echinosophora koreensis (Nakai) Nakai an endemic plant with limited distribution in some parts of the Korean Peninsula, is designated as "Endangered" species on the IUCN Red List. The species is under the threat of deterioration in nature due to various environmental changes causing loss of natural habitats. We investigated the distribution pattern and population structure of E. koreensis to serve as a basic reference for identifying the dynamics and persistence of natural populations of this species in the future. To determine the characteristics of the E. koreensis population, we laid two to three large plots sized 20m×30m on the ridgeline as the reference in Yanggu, Chuncheon, and Hongcheon and laid four to seven small quadrats sized 1m×1m on the transect. A total of 530 plots were laid, 10 each at 2m interval, to measure the number of the stems, the number of fruiting, height, and other factors. The collected distribution information was compared with the existing IUCN assessed categories by applying IUCN Red List ver 3.1 Criteria B. The average population density of the three surveyed areas was 3.47 stem/㎡; the density of each area was 3.95 stems/㎡ in Yanggu, 3.37 stems/㎡ in Chuncheon, and 2.87 stems/㎡ in Hongcheon. The number of fruiting per stem was 0.0038, indicating only 7 fruits out of 1,837 stems and that vegetative reproduction is likely to be more dominant than sexual reproduction. The distribution tendency of population density in the small plots in three surveyed areas showed that the density of E. koreensis tended to decrease toward the center of the forest with low crown openness and around the mountain ridge with high crown openness. It indicated that the quantity of light could be a very important factor for the growth of individuals of this species. The analysis of the heights of individuals present in the surveyed plots showed a range of 2.3 ~ 68.5cm and an average of 20.1cm. An analysis on the stage-structure of the E. koreensis population based on the sieve height found that the appearance frequency decreased with increasing height above 15 ~ 20cm and that the percentage of individuals lower than 10cm, which were presumed to be seedlings, was severely low, indicating a necessity of study on the population sustainability based on the monitored data. The occupied area calculated with the collected species distribution information was 200㎢, indicating the EN category according to the IUCN Red List Reference B.