• Journal of Environmental Science International
• /
• v.28 no.5
• /
• pp.495-502
• /
• 2019

This study was conducted to investigated the possibility of inactivating wilt germs (Fusarium oxysporum f. sp. radicis lycopersici) using Dielectric Barrier Discharge (DBD) plasma in a hydroponic system. Recirculating hydroponic cultivation system for inactivation was consisted of planting port, LED lamp, water tank, and circulating pump for hydroponic and DBD plasma reactor. Two experiments were conducted: batch and intermittent continuous process. The effect of plasma treatment on Total Residual Oxidants (TRO) concentration change, Fusarium inactivation and growth of lettuce were investigated. In the batch experiment, most of the Fusarium was inactivated at a TRO concentration of 0.15 mg/L or more at four-day intervals. There was no change in lettuce growth after two times of plasma treatment for one week. The intermittent continuous experiment consisted of 30-minute, 60-minute, and 90-minute plasma treatment in 2 day intervals and 30-minute treatment a one-day; most of the Fusarium was inactivated only by treatment for 30-minute every two days. However, if inactivation under $10^1CFU/mL$ is required, it will be necessary to treat for 60 minutes in 2 day intervals. The plasma treatment caused no damage to the lettuce, except the 30 min plasma treatment ay the one-day interval. It was considered that the residual TRO concentration was higher than that of the other treatments.

• Journal of Bio-Environment Control
• /
• v.11 no.1
• /
• pp.18-22
• /
• 2002

Diseases occurrence of hydroponic culture was less than that of soil culture, especially gummy stem blight, which was 39.9-53.3% of infection rate at soil culture, was not almost observed at hydroponic culture. Development of fermented fruit was higher at Shintozoa, Hongtozoa and self-rooting seedling in order at soil cultured but critically dropped at hydroponic culture without rootstock sort. Therefore proper moisture management at root zone can decrease the development of fermented fruit.

• Journal of Multimedia Information System
• /
• v.5 no.3
• /
• pp.215-220
• /
• 2018

This work presents a smart water quality sensor for hydroponic plant growing applications. The proposed sensor can effectively measure pH level and electrical conductivity of the water solution. The micro-controller incorporated in the sensor processes the raw sensor data, and converts it into a readable format. In addition, through the mobile interface realized using a WiFi module, the sensor can send data to the web server database that collects and stores the data. The data stored in the web server can be accessed by a personal computer or smart phone. The prototype sensor has been implemented, and the operations have been verified under an actual hydroponic plant growing application.

• Journal of Environmental Science International
• /
• v.33 no.5
• /
• pp.323-332
• /
• 2024

Circulating hydroponic cultivation has the advantage of reducing soil and water pollution problems caused by discharge of fertilizer components because the nutrient solution is reused. However, cyclic hydroponic cultivation has a low biological buffering capacity and can cause outbreaks of infectious root pathogens. Therefore, it is necessary to develop technologies or disinfection systems to control them. This study used dielectric barrier discharge plasma, which generates various persistent oxidants, to treat Fusarium oxysporum f. sp., a pathogen that causes wilt disease. Batch and intermittent continuous inactivation experiments were conducted, and the results showed that the total residual oxidant was persistent in intermittent plasma treatment at intervals of 2-3 days, and F. oxysporum was treated efficiently. Intermittent plasma treatment did not inhibit the growth of tomatoes.

• The Journal of the Korea Contents Association
• /
• v.21 no.4
• /
• pp.424-433
• /
• 2021

The aim of this study is to explores the possibility of applying new aquaponics using guppies, a tropical fish breeding as companion fish at home, different from the aquaponics system using fish species such as loach, carp, and catfish for commercial purposes. To facilitate the application of Aquaponics at home, a system was established by connecting a water tank, water plants, hydroponic pots, plant growth LEDs, and Arduino sensors using Internet of Things(IoT) technology. As a hydroponic crops, lettuce that can be easily obtained and consumed at home was selected. In order to confirm the applicability of aquaponics using tropical fish, the growth rates of hydroponic crops in the same environment were compared as a control. The growth rate of aquaponics crops using tropical fish was about 77.4% of that of hydroponic crops. This will produce the same effect as hydroponic cultivation if conditions correspond with enough fish quantity to feed plant and appropriate pH control for growth are met. It can be seen that, and in the future, it can be used to develop an Aquaphonics standard system applicable at home.

• Korean Journal of Environmental Agriculture
• /
• v.41 no.3
• /
• pp.191-198
• /
• 2022

BACKGROUND: Plants can be grown using a culture medium without soil using a hydroponic system. Crop production by the hydroponic system is likely to increase as a means of solving various problems in the agricultural sector such as aging of rural population and climate change. Different water sources can be used to prepare the culture medium used in the hydroponic system. Therefore, it is necessary to study the effect of different water sources on crop production by the hydroponic system in order to explore the applicability of various water resources. METHODS AND RESULTS: Lettuce was cultivated by the hydroponic system and three different water sources [tap water (TW), bottled water (BW), and groundwater (GW)] were used to compare the effect of water sources on lettuce growth. The three kinds of waters with a nutrient solution (TW-M, BW-M, GW-M) were also used as the media. After the six-week growth period, the lettuce length and weight, the number of leaves, and the contents of chlorophylls and polyphenols were compared among the different media used. The lettuces did not grow in the waters without the nutrient solution. In the media, the lettuce growth and the contents of chlorophylls were affected by the different water sources used to prepare the media, while the contents of polyphenols were not affected. The absorbed amounts of ions by lettuces, especially Ca and Zn ions, and the dry weight of the harvested lettuces showed a strong positive correlation. CONCLUSION(S): Overall, this study shows that different water sources used for growing lettuce in a hydroponic system can affect lettuce growth. Further studies on the enhancement of crop qualities using different water sources may be required in future studies.

• Korean Journal of Environmental Agriculture
• /
• v.24 no.1
• /
• pp.24-28
• /
• 2005

Waste of the hydroponic solution from the plastic film house cultivation was recycled to grow the red pepper(Capsicum annum L.) in upland fields as supplement for plant nutrients and irrigation sources. Application of hydroponic waste solution increased the pH and EC of the soils, coupled with the increases in the concentrations of exchangeable cations(Ca, Mg, and K), total nitrogen, $NH_4-N,\;and\;NO_3-N$. Growth and yield of red pepper were highest when the treatment of chemical fertilizer(70%) was combined with hydroponic waste solution(30%). Amounts of the daily producing hydroponic waste solution were 2,880 L $ha^{-1}\;day^{-1}$ from the experimental facilities and this could irrigate $409.86m^2$ of area to compensate for the amount of water loss by evapotranspiration(3%). The overall results demonstrated that hydroponic waste solution could be recycled as plant nutrients and irrigation water resources for enhancing soil fertility and environmental quality.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2003.09a
• /
• pp.102-106
• /
• 2003

The uptake of $^{14}C$-2, 4, 6-trinitrotoluene (TNT) in hydroponics was studied using onion plants. Of the total TNT mass (5 $\mu\textrm{M}$ concentration), 75% was in the roots, 4.4% in the leaves, and 21% in the external solution at 2 days, The percent distribution in roots was lower with higher concentration in the external solution, but in leaves it was comparable at all concentrations (5-500 $\mu\textrm{M}$). Root concentration factor (RCF) in hydroponics was more than 85 in constant hydroponic experiment (CHE) at 5 $\mu\textrm{M}$ and 150 in non-constant hydroponic experiment (NHE) at 5 $\mu\textrm{M}$. The maximum RCF values in the hydroponic system were greater with lower solution concentration. Transpiration stream concentration factor (TSCF) values in the present study (NHE only: 0.31-0.56) were relatively similar to the values with predicted values (0.43-0.78), increasing with higher external TNT concentration. For phytotoxicity tested in hydroponics and wet paper method, 500 $\mu\textrm{M}$ was toxic to onion plant, 50 $\mu\textrm{M}$ was non-toxic for plant growth but limited the transpiration rate, and 5 $\mu\textrm{M}$ was non-toxic as control.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2016.05a
• /
• pp.211-212
• /
• 2016

Due to a lack of objective and adequate study on the physical effects on hydroponic polyurethane waterproofing material water mixture ratio, construction site workers are having to rely on their hands-on experience to determine a mixture ratio, resulting in difficulty of maintaining quality management. Particularly in cases of rooftop exposed type hydroponic polyurethane materials, the varying temperature conditions make it further difficult for quality management control. in this regard, this study conducts tensile strength testing and compares the tensility change rates hydroponic polyurethane waterproofing materials with various water mixture ratios ranging from 0%~50% and exposed to alternating temperature change between -20℃ to 60℃ in the span of 1 hour after curing for 14 days.

• Journal of Environmental Science International
• /
• v.22 no.7
• /
• pp.801-810
• /
• 2013

To improve the physical and chemical properties of the soil and increasing water-retaining property of the soil, Superabsorbent synthetic polymeric materials have been used. The experiment carried out from April to July 2012 after the influence evaluation of Superabsorbent synthetic polymeric materials to vines plant. The result shows that the study of Hedera japonica Tobler, the growth and the survival rates rank as media > hydroponic > superabsorbent synthetic polymers, and the growth and the survival rates are considerably pessimistic in the experiment of hydroponic and superabsorbent synthetic polymers. In the study of Trachelospermum asiaticum var. intermedium, the growth and the survival rates rank as hydroponic > media > superabsorbent synthetic polymers, the difference between the experiment of hydroponic and is very small and the survival rates are not very good in the experiment of superabsorbent synthetic polymers. In the study of Euonymus fortunei var. radicans Rehder,it is insignificantly difference among the different of planting based. Judging from these results, the differences are depending on the species of plants. The thesis holds that the characteristics of plant should be considered in plant cultivation and soil improvement in the future, and it is desirable to use the appropriate mixing ratio of soil in soil improvement as well.