• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.35 no.5
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• pp.459-465
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• 2022

This paper reports a method to use a wireless sensor network deployed in the field to real-time monitor soil moisture, warning when the moisture level reaches a specific value, and wirelessly controlling an additional device (LED or water supply system, etc.). In addition, we report all processes related to wireless irrigation system, including field deployment of sensors, real-time monitoring using a smartphone, data calibration, and control of additional devices deployed in the field by smartphone. A commercially available open-source Internet of Things (IoT) platform, NodeMCU, was used, which was combined with a 9V battery, LED and soil humidity sensor to be integrated into a portable prototype. The IoT-based soil humidity sensor prototype deployed in the field was installed next to a tree for on-site demonstration for the measurement of soil humidity in real-time for about 30 hours, and the measured data was successfully transmitted to a smartphone via Wifi. The measurement data were automatically transmitted via e-mail in the form of a text file, stored on the web, followed by analyses and calibrations. The user can check the humidity of the soil real-time through a personal smartphone. When the humidity of a soil reached a specific value, an additional device, an LED device, placed in the field was successfully controlled through the smartphone. This LED can be easily replaced by other electronic devices such as water supplies, which can also be controlled by smartphones. These results show that farmers can not only monitor the condition of the field real-time through a sensor monitoring system manufactured simply at a low cost but also control additional devices such as irrigation facilities from a distance, thereby reducing unnecessary energy consumption and helping improve agricultural productivity.

• Journal of the Korea Safety Management & Science
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• v.24 no.4
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• pp.49-59
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• 2022

Mt. Umyeon is a low-altitude mountain near a residential area, and the actual forest area is not large due to the fact that development for use as a living green space is being completed and in progress across the mountain, so the buffering action for landslides was weak. The unit was located at the top of Mt. Umyeon, and there were reports of contents related to the military unit in some accident areas. Some experts suggested that the landslide that started on the cut side of the unit could be one of the causes of the landslide at Mt. Umyeon. It is presumed that there was a sudden collapse of trees that had fallen due to erosion inside the valley. In the case of the Umyeon landslide, localized torrential rain is the biggest cause, but the fact that it suffered a lot of damage is the result of no preemptive measures. In particular, it can be said that the damage was caused by the concentration of residential and commercial facilities due to the unplanned urban expansion without prior review of the feng shui geography of settlement areas. The important lesson we have learned is that we should recognize nature as living things and live in harmony and coexistence between humans and nature through understanding and cooperation. Adapting to changes in the environment can survive, but if it doesn't, it will be slaughtered. As such, geography influences changes in feng shui. Changes in feng shui have a profound effect on not only humans but also the natural ecosystem.

• Tunnel and Underground Space
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• v.34 no.4
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• pp.267-282
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• 2024

This study aims to develop a wireless communication system for long-term monitoring of high-level radioactive waste disposal facilities. Conventional wired sensors can lead to a deterioration in buffer quality and management difficulties due to the use of cables for power supply and data transmission. This study proposes the adoption of a wireless communication system and compares the received signal strengths within bentonite using modules such as WiFi, ZigBee, and LoRa. Increases in dry density of bentonite and distance between transceivers led to reduced received signal strength. Additionally, using the low-frequency band exhibited less signal attenuation. Based on these findings, a conceptual design for a wireless network-based THM integrated sensor system was proposed. Results of this study can be used as foundational data for long-term monitoring of disposal facility.

• Korean Journal of Environment and Ecology
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• v.25 no.1
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• pp.102-110
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• 2011

The study aims to provide future implications for planning nature trails called Dullegil in the national park located in the city in Korea as new visiting culture for sustainability of environment and use. The telephone survey used quota sampling with 300 Seoulite ages from 20 to 69 by area, gender, and age, which was conducted to find out the perception on a Dullegil in Bukhansan National Park. The result shows more than 65% of Seoulite go climbing and aiming the mountain top as a general visitor behavior. The intention to use Dullegil was very high at 58%, which forecasts the use of Dullegil as a substitute for a trail to the intensified mountain top. However, the effectiveness of Dullegil to divert intensive use could be limited as the major group of climbers showed relatively low intention to use Dullegil as an alternative. As for the management direction, majority favors balanced management between use and conservation, even if conservation was preferred to use. Most important guiding principle for building Dullegil was conservation of environment, the planning direction should be oriented to conserve the ecological environment of Bukhansan, and to enjoy its value. Facilities for visitor safety was most needed. Most preferable time and length were 1~3 hours and 11~20km, each. This study has a limitation as the site was limited to Bukhansan and potential demand for use was analyzed with the sample of Seoulite only. To come up with the results generally applicable, more detailed future researches by the visitor segmentation, use behavior, and demand are needed.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.4
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• pp.86-99
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• 2016

This study was for analyzing the external environment and internal space structure and improving the way of use efficiency in waterfront through the Dragon boat festival to utilize waterfront actively. Through from the four target area, Hongkong, Busan, Incheon and Daejeon, this study was for an importance and satisfaction analysis for users about the element effect on the waterfront use efficiency and the contribution to cultural contents revitalization of waterfront by giving basic data. The result is as follows. First, in the importance analysis about 12 items, modern cultural infra around the waterfront was ranked highest, 8.26 and waterfront landscape, square & openspaces, convenience facilities, transport, green area, quality of viewing space, historic resources, pedestrian, suitability of width, wave, depth, water quality, berth & mooring were ranked in descending order. Second, waterfront landscape was interpreted by rather the external environmental impact according to city size than the matter of spatial structure in target area and judged as an important factor effect on site selection for waterfront. In the analysis of waterfront landscape, the reason of the high satisfaction about domestic target area was that riverside parks were recently made considering their waterfront activities. Viewing space was major infra where people could experience the pleasant waterfront and watch dynamic water leisure sports like Dragon boat three dimensionally and was thought to be improved for the use efficiency. Third, tourism resources were very important element that affect the use efficiency of waterfront, so waterfront users react sensitively to modern tourism resources rather than to historic resources. This meant that tourism infrastructure for shopping and leisure of the young affected the use efficiency of waterfront, so Hongkong and Busan were in a better position in terms of using waterfront that was near the tourism infrastructure. Fourth, in the analysis of traffic accessibility, both Hongkong and Busan were high evaluated in terms of excellent traffic accessibility by subway. Daejeon was low rated in terms of the satisfaction of use efficiency, because of the relative lower place awareness compared with transportation infrastructure. In Hongkong, waterfront was connected with downtown and in Busan, housing complex and shopping centers were located in the place for users in an easily accessible on foot, so the satisfaction was high-pitched. Finally, in the importance of water surface width and the analysis of satisfaction, except Incheon, all the three were over 200m in width of water surface and this meant the surface width above certain level was interpreted to interrupt the concentration of enjoying the water leisure sports. In the analysis of surface condition such as water quality, water depth and wave, through a survey, Busan had a problem with water quality and Gapcheon in Daejeon had a problem with optimal water depth by the festival participants.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.23 no.3
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• pp.23-43
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• 2020

The purpose of this paper is to create ecological values for urban rivers. For this, the paper looks into river bed structures and how nearby lands are used. This study was performed to set the specific sections for analysis through a field investigation of the infrastructure conditions, surrounding land use, and the inter habitat structure of Seongnaecheon(Stream). A total of 780 individuals from 31 species of wild birds appeared in Seongnaecheon(Stream). According to foraging guild's habitat, there were 9 species of water, 8 types of water edges, 5 types of crowns, 5 types of shrubs, 2 types of tree trunks, 2 types of birds of raptors, and 355 individuals of water, 243 shrubs, 90 crowns, 84 water edges and 5 raptors. Many water birds were observed at the site where the Seongnaecheon(Stream) sandy plains and wetland herbaceous area were developed and the open water was secured. Most of the forest birds appeared on levee slope connected with forest around and riverside with fewer facilities for use. The species diversity index of Shannon, the entire section of Seongnaecheon(Stream), was 2.2697 and the downstream ecological landscape conservation area of Seongnaecheon(Stream) was found to be useful as a habitat for wild birds in the city compared to other sections. Some sections of Seongnaecheon (Stream) had low species diversity index due to lack of green space and surrounding urbanization areas. In choosing target species, I researched the special features of the habitats and the habitation structure of wild birds in each zone. Regarding detailed plans, by classifying the breeding place & roosting site and the roosting site & shelter that took account of the inhabitation characteristics of the target species in different sections, this paper suggested the major plant species and multilayer planting structures. Moreover, this study proposed the development of habitats for water birds and forest birds along with the connection of the green network for improving the Eco-corridor linkage and inhabitation features in Seongnaecheon(Stream).

• Journal of the Korean Applied Science and Technology
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• v.35 no.3
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• pp.816-825
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• 2018

Recently, it was emerged to need the necessity of LPG residues management due to the finding some substances such as rust. This study is performed to investigate the characteristics of LPG residues in the production and distribution stage of LPG. For the qualitative analysis of LPG residues, it was operated to be set up the analysis conditions(the flow rate, etc) of GC-MS and was performed to analyze the component of LPG residues. From the analysis result using GC-MS, it was shown that the component of LPG residues was turned out the plasticizer to be used in the rubber manufacturing process. The inorganic components of LPG residues were analyzed using ICP-OES. At the results of inorganic analysis, it was shown that the Si element was detected, which was presumably derived from defoamers used mainly in the LPG production. Also, the P and Zn element, which are estimated to be components of grease additives used for filling facilities, were also partially detected. No trace of rusting was detected in the LPG residues in the production and distribution stages analyzed in this study. But, as plasticizers and grease additives can affect to the LPG fuel system in vehicles, it will be necessary to use the proper quality of rubber and to expand the use of low boiling grease additives.

• Journal of the Korean Institute of Landscape Architecture
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• v.27 no.5
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• pp.1-11
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• 2000

The aim of this study is to suggest guidelines of bicycle lanes in terms of landscape architecture with special reference to Kyongju. The research is mainly based on landscape satisfaction factors analysis regarding 16 variables and 10 slide photos of bicycles lanes. The 43 students of Landscape Department in Kyungpook National University were selected for the research. The major research findings are as follows; 1. Satisfaction degree of 16 variables are assessed in terms of semantic differential scale. The assess group is generally satisfied with variables concerning bicycle lane environment such as $\ulcorner$inclination of the lane (5.2)$\lrcorner$and $\ulcorner$road pavement conditions (5.1)$\lrcorner$. But the group expresses rather low satisfaction degree on the variables related lanes' surrounding landscape such as $\ulcorner$visual variety (3.9)$\lrcorner$, spacious resting place (3.7)$\lrcorner$ and $\ulcorner$variety of facilities (3.1)$\lrcorner$. 2. The level of satisfaction degree regarding 16 variables and 10 photos shows that the male gives relatively higher satisfaction degree than the female group. But there is no statistical significance between the group regarding satisfaction degree of each variable and photo except 4 variables and 2 photos. 3. The assess group gives the highest satisfaction degree on the$\ulcorner$no. 10 slide (6.5)$\lrcorner$ and the lowest on the $\ulcorner$no. 7 slide (2.7)$\lrcorner$. The two photo shows variables of more than 4 points difference of satisfaction degree, such as $\ulcorner$good looking planting threes (4.8)$\lrcorner$, $\ulcorner$enough shadows (4.8)$\lrcorner$ and $\ulcorner$comfortable atmosphere(4.1)$\lrcorner$. 4. $\ulcorner$Aesthetic and amenity factor$\lrcorner$, $\ulcorner$use condition factors$\lrcorner$, $\ulcorner$ike lane environment factors$\lrcorner$, and $\ulcorner$inclination and open view factors$\lrcorner$are the main four factors influencing landscape satisfaction of bicycle lane. Regression model using factor scores for landscape satisfaction degree of bike lane is S(Satisfaction degree)=4.526+1.099(aesthetic and amenity factor)+0.720(use condition factors)+0.486(bike lane environment factors)+0.048(inclination and open view factors($R^2$=0.811).

• Journal of the East Asian Society of Dietary Life
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• v.8 no.1
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• pp.36-50
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• 1998

The purpose of this study was to investigate quantity food production practices in foodservices by analysing the menus of April, 1996, The questionnaire was developed and responded to by 96 dietitians in Sangju, Munkyung, Gumee, Kimchun, and Andong during November, 1996. The survey was performed by simple random samplings. The results were as follosw; 1. Hospitals and industry served food for thirty days and schools for twenty days. Kimchi was a select-menu for hospitals and one side dish for industry and schools. The type of menu was a single use menu which consisted of cooked rice, soups and three side dishes. 2. The most frequently used ingredients were green onions, rice, carrots, onions, Korean radish roots, pork, eggs, glutinous rice, and milk. Kimchis were served most frequently in all food services and cooked rices and soups were next. 3. The age of most of the respondents was 26 to 30.54.2% of subjects were juniou college graduates and 77.1% were single. Fifty seven point three percent of the dietitians lived with family relatives, or friends. 87.5% of the dietitians had been working for 1 to 5 years. 4. Most foodservices were self-operated. The number of meals served was determined by meal coupon counting in hospitals(37.5%), meal board counting in industry(29.2%), and attendance card counting in schools(41.1%) The cost of sales per meal was approximately 2,450 won in hospitals and was approximately 1,100 won in industry and schools. The average number of days per menucycle was 7.4 in hospitals. 10.3 in industry and 25.5 in schools. Hospitals, industry, and schools held about 118, 265 and 263 recipes respectively. The average number of dietitians was 2.6 in hospitals and 1.0 in industry and schools. Except for the number of recipes, the general practices of foodservices were significantly different(P<0.05). 5. In the general quantity food production, food and seasonings measuring was hardly done. the percentage of foodservices using chemical seasonings was higher in hospitals and industry than in schools. the most important concern was taste, Registered cooks were employed in 75% of schools but only 50.0% in hospitals and 20.8% in industry. Most of the dietitians respinded that their cooks skill was not bad. The education of unregistered cooks was performen once or two times a month in hospitals and industry, and in schools performed everyday. The problem when educating cooks was the lack of cooking skill of the dietitians in schools, and the lack of time in hospitals, and the negative attitude toward education in industry. The method for improving cooking in all foodservices was OJT, or the extension of education facilities and the development and dissemination of standard recipes. The frequency of throwing away leftovers was higher in hospitals. But in industry, the frequency of saving leftovers was higher. 6. Though all foodservices have standard recipes, the number that used them was low, Another problem is that standard recipes resulted in leftovers. The inconveniences of using standard recipes were the difficulty of applying standard recipes to various numbers of customers the complication of use, or facility insufficiency.

• Journal of Veterinary Clinics
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• v.32 no.4
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• pp.324-329
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• 2015

The primary aim of this study was to investigate biosecurity practices in pig farms and to determine the major risk factors associated with PCV2 infection for a sampled swine population in Korea. To this end, we analyzed data from a cross-sectional study of 296 farrow-to-finish farms, which was conducted between March and September 2014 to explore the prevalence of swine disease at farm level. Face-to-face interviews by on-site visit of trained veterinarians were conducted with the farm owners or managers using a standardized questionnaires with information about basic demographical data and management practices. Farms were classified as negative or positive through the use of infection profiles that combined data on serological testing including PCR antigen test result, antibody titer and sero-conversion pattern at each age category taking into account vaccination status. Data were analyzed using multivariate ordinal logistic regression. Results from this study indicated that biosecurity level of the farms was considered not good given low compliance of the biosecurity programs and facilities in the farm: off-site removal of dead stocks (7%), off-site location of storage facility for incoming feeds (12.6%), off-site pick-up location for finishers (19.3%), restrictions on feed supplier vehicles for farm entrance (19.6%), restriction of finisher trucks entering the farm (22.4%), and restriction on manure disposal trucks entering the farm (26.4%). In the final model (n = 255), allowance of finisher truck driver to the pig unit had increased risk of infection (OR = 2.4, 95% CI 1.22-4.67) whereas farms with a sign forbidding the entrance had decreased risk of infection (OR = 0.19, 95% CI 0.10-0.58). Further comprehensive research with larger sample size is required to better understand the multifactorial characteristic that some predisposing risk factors that were not available in this study. To the best knowledge of the authors, this was the first study to use empirical data to report risk factors associated with PCV2 infection in the Korean pig farms. Results from the current study could be used to decide optimal biosecurity measures to reduce the impact of PCV2 infection to farmers and policy makers.