• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.1
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• pp.72-79
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• 2021

The increasing use of deicing salts has caused various environmental problems, including crop damage along the motorway where deicing salts are sprayed during winter. Deicing salts used on roads have been reported to negatively affect crops, but little information is known about their impact on crops. A seedling emergence assay was conducted to evaluate the effects of deicing salts on crops using oilseed rape (Brassica napus) as a model plant. We tested five chloride deicing salts consisting of NaCl, CaCl2, or MgCl2 and 1 non-chloride deicing salt (SM-3) at a range of concentrations (25, 50, 100, 200, and 400 mM), and untreated control. Regardless of deicing salts, they significantly delayed and reduced seedling emergence of oilseed rape with increasing salt concentration. Non-linear regression analysis of seedling emergence with a range of salt concentrations by fitting to the log-logistic model revealed that the chloride deicing salts reduced seedling emergence more than the non-chloride deicing salt SM-3. The GR50 value, the concentration causing 50% seedling emergence, of SM-3 was 47.1 mM, while those of the chloride deicing salts ranged from 30.7 mM (PC-10) to 37.5 mM (ES-1), showing approximately 10 mM difference between non-chloride and chloride deicing salts. Our findings suggest that seedling emergence assay is a useful tool to estimate the potential damage caused by deicing salts on crops.

• Journal of the Economic Geographical Society of Korea
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• v.25 no.1
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• pp.109-130
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• 2022

The Vietnamese government has proposed contract farming through a new type of cooperative as an institutional innovation which aims to restructure the agricultural sector. However, policy changes often impact farmers, who bear the primary effects of the transition process. Understanding households' strategies for land use and livelihood is crucial for policymaking in the agricultural development field. This study was conducted in the rural Binh Dao commune in Central Vietnam. We analyzed household members' labor force changes and their livelihood behaviors after their participation in a contract farming scheme using qualitative analysis methods combined with geographic information system (GIS) support, based on secondary data and in-depth interviews of 190 farmers. Simultaneously, we created a digital map of the cooperative's production area to investigate changes in land use and production activities. The findings show that contract farming shaped the vertical coordination of the value chain from the farmers to the cooperative and agricultural product trading companies. Subsequently, it encouraged land use and labor efficiency due to mechanical support. In addition, it also increased productivity and protected farmers from market risks. However, despite its positive effects on agricultural productivity in this case, the contract farming scheme could not achieve the restructuring of the rural labor force toward non-agricultural sectors. Ironically, farmers in the Binh Dao commune tended to increase cultivable land during the agricultural restructuring program, rather than switching their labor forces to non-agricultural sectors. The lack of stable non-farming job opportunities in rural Vietnam results in challenges to the efficiency of agricultural restructuring programs. Consequently, farmers in the Binh Dao commune are still smallholder farmers, depending on the family labor force.

• Korean Journal of Remote Sensing
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• v.38 no.2
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• pp.179-188
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• 2022

Global warming causes climate change and increases extreme weather events worldwide, and the occurrence of heatwaves and droughts is also increasing in Korea. For the monitoring of extreme weather, various satellite data such as LST (Land Surface Temperature), TCI (Temperature Condition Index), NDVI (Normalized Difference Vegetation Index), VCI (Vegetation Condition Index), and VHI (Vegetation Health Index) have been used. VHI, the combination of TCI and VCI, represents the vegetation stress affected by meteorological factors like precipitation and temperature and is frequently used to assess droughts under climate change. TCI and VCI require historical reference values for the LST and NDVI for each date and location. So, it is complicated to produce the VHI from the recent satellite GK2A (Geostationary Korea Multi-Purpose Satellite-2A). This study examined the retrieval of VHI using GK2A AMI (Advanced Meteorological Imager) by referencing the historical data from VIIRS (Visible Infrared Imaging Radiometer Suite) NDVI and LST as a proxy data. We found a close relationship between GK2A and VIIRS data needed for the retrieval of VHI. We produced the TCI, VCI, and VHI for GK2A during 2020-2021 at intervals of 8 days and carried out the interpretations of recent extreme weather events in Korea. GK2A VHI could express the changes in vegetation stress in 2020 due to various extreme weather events such as heatwaves (in March and June) and low temperatures (in April and July), and heavy rainfall (in August), while NOAA (National Oceanic and Atmospheric Administration) VHI could not well represent such characteristics. The GK2A VHI presented in this study can be utilized to monitor the vegetation stress due to heatwaves and droughts if the historical reference values of LST and NDVI can be adjusted in a more statistically significant way in the future work.

• Korean Journal of Remote Sensing
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• v.38 no.6_3
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• pp.1817-1826
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• 2022

After the hydrogen fluoride leak in Gumi in 2012, the government has been systemizing the disaster management system, such as responding to and managing chemical accidents. In particular, the Ministry of the Interior and Safety (MOIS) is in charge of evacuation of residents following chemical accidents based on the Framework Act on Management of Disaster and Safety. In this study, an application plan was presented to support and utilize the decision-making support for evacuation of residents after a chemical accident using the chemical accident investigation equipment of the National Disaster Management Research Institute (NDMI). In the equipment operation system for scientific information collection due to chemical accidents, the roles and purpose of use of long/short distance measurement equipment were presented according to regular and emergency situations. Using the data acquired through long/short distance measurement equipment, it can be used as basic data for resident evacuation decision-making by monitoring whether chemicals are detected in an emergency and managing data on detected substances by company in a regular situation. As a result of measuring chemical substances in order to verify on-site usability by equipment only for the regular operation system, it was confirmed that real-time detection of chemical substances is possible with long distance measuring equipment. In addition, it was confirmed that it was necessary to check the measurable distance and range of the equipment in the future. In the case of short distance measurement equipment, hydrocarbon-based substances were mainly detected, and it was confirmed that it was measured at a higher level in Ulsan-Mipo National Industrial Complex than in Onsan National Industrial Complex. It is expected that it can be used as basic data to support decision-making in the event of chemical accidents through continuous data construction in the future.

• Journal of the Korean earth science society
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• v.43 no.2
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• pp.239-252
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• 2022

Quality control methods for the first G-band vapor radiometer (GVR) mounted on a weather aircraft in Korea were developed using the GVR Precipitable Water Vapor (PWV). The aircraft attitude information (degree of pitch and roll) was applied to quality control to select the shortest vertical path of the GVR beam. In addition, quality control was applied to remove a GVR PWV ≥20 mm. It was found that the difference between the warm load average power and sky load average power converged to near 0 when the GVR PWV increased to 20 mm or higher. This could be due to the high brightness temperature of the substratus and mesoclouds, which was confirmed by the Communication, Ocean and Meteorological Satellite (COMS) data (cloud type, cloud top height, and cloud amount), cloud combination probe (CCP), and precipitation imaging probe (PIP). The GVR PWV before and after the application of quality control on a cloudy day was quantitatively compared with that of a local data assimilation and prediction system (LDAPS). The Root Mean Square Difference (RMSD) decreased from 2.9 to 1.8 mm and the RMSD with Korea Local Analysis and Precipitation System (KLAPS) decreased from 5.4 to 4.3 mm, showing improved accuracy. In addition, the quality control effectiveness of GVR PWV suggested in this study was verified through comparison with the COMS PWV by using the GVR PWV applied with quality control and the dropsonde PWV.

• Research in Plant Disease
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• v.28 no.3
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• pp.113-121
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• 2022

Rice blast is a major plant disease that occurs worldwide and significantly reduces rice yields. Rice blast disease occurs periodically in Korea, causing significant socio-economic damage due to the unique status of rice as a major staple crop. A disease outbreak prediction system is required for preventing rice blast disease. Epidemiological investigations of disease outbreaks can aid in decision-making for plant disease management. Currently, plant disease prediction and epidemiological investigations are mainly based on quantitatively measurable, structured data such as crop growth and damage, weather, and other environmental factors. On the other hand, text data related to the occurrence of plant diseases are accumulated along with the structured data. However, epidemiological investigations using these unstructured data have not been conducted. The useful information extracted using unstructured data can be used for more effective plant disease management. This study analyzed news articles related to the rice blast disease through text mining to investigate the years and provinces where rice blast disease occurred most in Korea. Moreover, the average temperature, total precipitation, sunshine hours, and supplied rice varieties in the regions were also analyzed. Through these data, it was estimated that the primary causes of the nationwide outbreak in 2020 and the major outbreak in Jeonbuk region in 2021 were meteorological factors. These results obtained through text mining can be combined with deep learning technology to be used as a tool to investigate the epidemiology of rice blast disease in the future.

• Journal of Appropriate Technology
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• v.7 no.2
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• pp.127-135
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• 2021

To respond to the threat of global warming, countries around the world are promoting the spread of renewable energy and reduction of carbon emissions. In accordance with the United Nation's Sustainable Development Goal to combat climate change and its impacts, global automakers are pushing for a full transition to electric vehicles within the next 10 years. Electric vehicles can be a useful means for reducing carbon emissions, but in order to reduce carbon generated in the stage of producing electricity for charging, a power generation system using eco-friendly renewable energy is required. In this study, we propose a smart electric mobility operating system integrated with off-grid solar power plants established in Tanzania, Africa. By applying smart monitoring and communication functions based on Arduino-based computing devices, information such as remaining battery capacity, battery status, location, speed, altitude, and road conditions of an electric vehicle or electric motorcycle is monitored. In addition, we present a scenario that communicates with the surrounding independent solar power plant infrastructure to predict the drivable distance and optimize the charging schedule and route to the destination. The feasibility of the proposed system was verified through test runs of electric motorcycles. In considering local environmental characteristics in Tanzania for the operation of the electric mobility system, factors such as eco-friendliness, economic feasibility, ease of operation, and compatibility should be weighed. The smart electric mobility operating system proposed in this study can be an important basis for implementing the SDGs' climate change response.

• Korean small business review
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• v.42 no.1
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• pp.79-105
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• 2020

While individual enterprises with different objectives each other within supply chains require a variety of resources to achieve their own seeking goals and performances, it is necessary to form interdependent relationships among the enterprises to secure the resources what they need, as the individual enterprises are supposed to have limitations on such as time, space and cost to secure all the resources. In this process, conflict possibilities rise and opportunistic behaviors increase due to those environmental factors such as unbalanced information among enterprises, limited rationality, pursuit of interests, and risk aversion. Those existing studies on conflicts in the field of supply chains have limitations in that they failed to present specific conflict management strategies based on the conflict types from the perspective of the conflict resolution mechanism as the studies have made only focused on investigating the causes of conflicts and the impact of conflicts on performance. In this study, therefore, it used the TKI model of Kilmann and Thomas(1977) to subdivide the conflict management strategies in the process of transactions within supply chains by enterprises, and looked into the impact on partnership and performance according to each strategy. As the results, it showed that those types of conflict management strategies such as concession type and cooperation type had a positive(+) impact on the relationship commitment as a factor of partnership, and it was identified that the relationship commitment had a positive(+) impact on performance. In other words, it can be considered that the enterprises making use of the concession type & the cooperation type conflict management strategies under the situation of conflict would be able to have a very positive impact on their performances if they can make good relationship commitment such as investments in and efforts for the sustainable relationship along with the conflict management, while recognizing the importance of relationship. The most important meaning of this study lies on in terms of that it would be contributable to strengthening the partnership between enterprises and minimizing the risk of supply chains caused by conflicts through these results from the study.

• Journal of Bio-Environment Control
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• v.31 no.3
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• pp.246-254
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• 2022

Domestic facility agriculture grows rapidly, such as modernization and large-scale. And the production scale increases significantly compared to the area, accounting for about 60% of the total agricultural production. Greenhouses require energy input to create an appropriate environment for stable mass production throughout the year, but the energy load per unit area is large because of low insulation properties. Through the rooftop greenhouse, one of the types of urban agriculture, energy that is not discarded or utilized in the building can be used in the rooftop greenhouse. And the cooling and heating load of the building can be reduced through optimal greenhouse operation. Dynamic energy analysis for various environmental conditions should be preceded for efficient operation of rooftop greenhouses, and about 40% of the solar energy introduced in the greenhouse is energy exchange for crops, so it should be considered essential. A major analysis is needed for each sensible heat and latent heat load by leaf surface temperature and evapotranspiration, dominant in energy flow. Therefore, an experiment was conducted in a rooftop greenhouse located at the Korea Institute of Machinery and Materials to analyze the energy exchange according to the growth stage of crops. A micro-meteorological and nutrient solution environment and growth survey were conducted around the crops. Finally, a regression model of leaf temperature and evapotranspiration according to the growth stage of leafy vegetables was developed, and using this, the dynamic energy model of the rooftop greenhouse considering heat transfer between crops and the surrounding air can be analyzed.

• Journal of Nutrition and Health
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• v.55 no.1
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• pp.141-154
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• 2022

Purpose: This study determined the relationships between maternal comprehensive feeding practices (CFP) and dietary practices of preschool children. Methods: Participants of the study were 227 mothers of children aged 3 to 5 years attending daycare centers and kindergartens in Seoul and Gyeonggi Province of Korea. The Comprehensive Feeding Practices Questionnaire was used to assess the maternal feeding practices. The Nutrition Quotient for Preschoolers (NQ-P) was measured to evaluate dietary practice and diet quality of children. Results: The balance of NQ-P for children was positively correlated with the modeling, restrictions for weight control, encouragement of balance and variety, pressure, and involvement among maternal CFP. Moderation of NQ-P was positively correlated with monitoring, modeling, teaching about nutrition, encouragement of balance and variety, environment, and involvement among maternal CFP. However, it was negatively correlated with emotion regulation, food as a reward, and child control in maternal CFP. Among maternal CFP, the environment of NQ-P was positively correlated with monitoring, modeling, teaching about nutrition, encouragement of balance and variety, environment, and involvement, and it was negatively correlated with emotion regulation. As a multiple regression analysis, maternal CFP that positively predicted balance of NQ-P indices were restricted for weight control, pressure, and involvement. Among maternal CFP, encouragement of balance and variety, and environment were positive predictors, while food as a reward, and child control were negative predictors for the moderation of NQ-P. Items of maternal CFP positively predicting environmental factors of NQ-P were monitoring and environment. Conclusion: Mothers are recommended to practice dietary guidance to their children, such as monitoring, modeling, teaching about nutritional information, recommendation of balance and diversity, healthy eating environment, and participation in meal plan and preparation, while they are advised not to conduct any adverse dietary guidance such as emotional control, compensation with food, child control, and food coercion.