• Journal of The Geomorphological Association of Korea
• /
• v.24 no.3
• /
• pp.61-81
• /
• 2017

Traditional approaches to surface moisture problems in the context of aeolian research have focused on the initiation of sand movement, developing various models for predicting threshold velocity on a wet surface. They have been unsatisfactory, however, in explaining field observations because they have not incorporated spatiotemporal variability of surface moisture, the interactions between transported sand grains and surface, and the role of aeolian transport in controlling surface moisture. As Nield (2011) showed, a simplified numerical model can be used to investigate this issue. This research aims to explore the feedback structures between aeolian transport and surface moisture using a modified sand slab model. Key modifications are the introduction of simultaneous updating scheme for all the slabs and moisture-assigning procedures with and without aeolian transport. The major findings are as follows. Moist surface conditions suppress sand slab movement, leading to the development of smaller-scale topography. Available sands for aeolian transport are determined by the vertical patterns of moisture content with its variations from groundwater to the surface. Sand patches on a wet surface act as a localized source area. Sand movement drives immediate changes in surface moisture rather than time-lag reponses, mostly when moist conditions are dominant.

• Korean Journal of Plant Resources
• /
• v.34 no.6
• /
• pp.608-615
• /
• 2021

Soil moisture control system including soil sensing and automatic water supply chain was constructed on open farmland and pot conditions. Soil moisture was controlled by the system showing over the soil moisture contents except 40% treatment. EC was gradually decreased by increasing cultivation days. On applying this system to control soil moisture, the growth and development characters of the bellflower were improved compared with control, cultivation without the automatic irrigation. Of the growth and development characters, plant height with water treatments was higher than that of control in 1st-year plants. Moreover, numbers of branch were increased by the increased soil moisture on farmland and pot condition. Capsule numbers for seed were best at 20%, 30% soil moisture treatment in 1st-year plants, and 20% to 50% treatment in 2nd-year plants. The construction of automatic soil moisture control system provide fundamental data for plant growth and development on open farmland soil condition.

• Journal of the Korean Society of Tobacco Science
• /
• v.8 no.2
• /
• pp.3-8
• /
• 1986

This study was carried out to investigate the effect of different soil moisture contents on the growth and chemical constituents of burley tobacco and on the protein pattern in tobacco leaf. Height, stem diameter, and largest leaf length of tobacco droughted from 45 to 60 days after transplanting was not recovered by rewatered amount of water supply from 60 to 75 days after transplanting, but leaf width enlarged. Dry weight per unit leaf area and total nitrogen content showed high values in low soil moisture, but total alkaloid contents were not different according to soil moisture contents. Soil moisture content didn't effect on the protein pattern of middle and upper leaves, but lower leaves showed the mild color and fewer numbers of the protein bands than those of midd1e and upper leaves.

• Transactions of the Korean hydrogen and new energy society
• /
• v.16 no.1
• /
• pp.82-91
• /
• 2005

Polymer membrane needs to maintain appropriate moisture. Insufficient moisture causes low conduction of hydrogen ion because of increased contact resistance between electrode and membrane by shrinking membrane, and abundant moisture decreases fuel cell performance as difficulty of diffusion reacting gas. Therefore, water controlling system is very consequential for the polymer membrane fuel cell. If hollow fiber membrane humidification is used between fuel and air lines, it is possible to supply heat to fuel and air by using thermal exchanger. It can supply appropriate humidity depending on operating temperature, and can recover heat from exhaust gas which contains water vapor and air. Because of simple structure of humidification system, this system can be easily applied in the PEMFC and cut down cost.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2000.11b
• /
• pp.423-429
• /
• 2000

The water conditioning experiments of brown rice were performed to verify the effect of brown rice conditioner and to decide the optimum operating variables for the conditioner. The initial moisture contents of 13-14%(wb) brown rice were used as experimental samples. The flow rate of brown rice passing through the conditioner was 2,940 kg/hr and water was supplied proportionally from 80 cc/min to 240 cc/min. The differences between expected and measured moisture contents were neglected except 0.25%(wb) of the maximum differences at 0.2920((cc/min)-water/(kg/min)'%-brown rice) of water supply rate. For the initial moisture contents of 13-14%(wb) brown rice, it was found that a proper water supply rate was 0.2415((cc/min)-water/(kg/min).%-brown rice) and the increments of whole rice was 2.3% compared to non conditioned ones. It was considered that the conditioning process did not influence the whiteness of milled rice because the whiteness differences between conditioned and non-conditioned milled rice were negligible.

• Journal of the Korean Society of Safety
• /
• v.18 no.2
• /
• pp.16-21
• /
• 2003

The object of this research is to prevent the industrial accidents which frequently occurred in breaking the coating in cement silo. Research was conducted to identify the cause of the coating formation, and the model experiment of aeration system was done to investigate the effect of moisture air on the coating formation. The results show that dehumidification of supply air in aeration system is the most important factor to suppress the coating formation, and the refrigerated low pressure air dryer applicable to the aeration system of cement silo was newly designed and developed. When this air dryer is applied to the cement silo, 88% of the moisture component of supply air can be reduced. Therefore the cleaning cycle extends over twice, and it contributes to the decrease of industrial accidents and cleaning cost.

• Korean Journal of Plant Resources
• /
• v.35 no.6
• /
• pp.762-769
• /
• 2022

Growth characters and ingredient contents of two-year-old bellflower (Platycodon grandiflorum) roots were investigated under both control and soil moisture treatment condition using soil moisture control system including soil sensing and automatic water supply chain in this study. Root diameter, fine root number, root length, fresh weight and dry weight of the plant were significantly influenced by the automatic water treatment, 20%, 30%, 40% and 50%, respectively. Ingredient contents of the two-year-old roots in bellflower plants were detected in the 20% and 50% of controlled soil moisture content. Contents of amino acids were decreased by the soil moisture treatment, meanwhile, contents of minerals were not showed significant decrease except for phosphorus content. Showing no difference in proline and tyrosine, fourteen of the amino acid contents were gradually decreased by the increased soil moisture contents, with significant decrease in serine, glycine, alanine, leucine, lysine and histidine at 20% treatment.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2022.05a
• /
• pp.8-12
• /
• 2022

Water loss is one of the typical but challenging problems in water management. To reduced water loss or increase water efficiency, the pilot projects were implemented in the TTD's irrigation area. Modern soil moisture technology and local level water user training were conducted together as a mean to achieve improved water efficiency. In terms of technology, soil moisture sensors and monitoring system were used to estimate crop water requirement to reduce unnecessary irrigation. This was found to save 16.47% of irrigated water and 25.20% of irrigation supply. Further improvement of water efficiency was gained by means of local level water user training in which stakeholders were engaged in the network of communications and co-planning. The lessons learnt from the TTD pilot project was translated into good water management practices at local level.

• Proceedings of the Korea Contents Association Conference
• /
• 2015.05a
• /
• pp.5-6
• /
• 2015

A GNSS based measurement system was constructed with not only the core sensors of a GNSS receiver, a TRS sensor and a soil moisture sensor but supplementary installation of power supply and radio communication for monitoring steep slope sites. The sensor combination extracts and transfers not only ground displacement in real-time but soil moisture content.

• Proceedings of the Korean Society of Agricultural Engineers Conference
• /
• 2000.10a
• /
• pp.187-192
• /
• 2000

The severity of drought could be evaluated by the accumulative rainfall method, soil moisture condition method, storage ratio method, and water supply restriction intensity method, etc. The pattern of drought could be forecast with the most similar pattern of accumulative rainfall out of the file of past rainfall history. The information that how much rainfall should be expected to overcome the present drought could be obtained from the reservoir storage ratio and soil moisture condition.