• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2006.06b
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• pp.311-316
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• 2006

This study was carried out to analyze the effect of wind load on the structural stability of a container crane according to the change of the boom shape using wind tunnel test and provided a container crane designer with data which can be used in a wind resistance design of a container crane assuming that a wind load at 75m/s wind velocity is applied on a container crane. Data acquisition conditions for this experiment were established in accordance with the similarity. The scale of a container crane dimension, wind velocity and time were chosen as 1/200, 1/13.3 and 1/15. And this experiment was implemented in an Eiffel type atmospheric boundary-layer wind tunnel with $11.25m^2$ cross-section area. Each directional drag and overturning moment coefficients were investigated and uplift forces at each supporting point due to the wind load were analyzed.

• Journal of Korean Society on Water Environment
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• v.35 no.3
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• pp.234-247
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• 2019

In a deep lake and reservoir, thermal stratification is of great importance for characteristics of hydrodynamic mixing of the waterbody, and thereby influencesvertical distribution of dissolved oxygen, substances, nutrients, and the phytoplankton community. The purpose of this study, was to project the effect of a future climate change scenario on water temperature, stratification strength, and thermal stability in the Soyanggang Reservoir in the Han River basin of South Korea, using a suite of mathematical models; SWAT, HEC-ResSim, and CE-QUAL-W2(W2). W2 was calibrated with historical data observed 2005-2015. Using climate data generated by HadGEM2-AO with the RCP 4.5 scenario, SWAT predicted daily reservoir inflow 2016-2070, and HEC-ResSim simulated changes in reservoir discharge and water level, based on inflow and reservoir operation rules. Then, W2 was applied, to predict long-term continuous changes of water temperature, in the reservoir. As a result, the upper layer (5 m below water surface) and lower layer (5 m above bottom) water temperatures, were projected to rise $0.0191^{\circ}C/year$(p<0.05) and $0.008^{\circ}C/year$(p<0.05), respectively, in response to projected atmospheric temperature rise rate of $0.0279^{\circ}C/year$(p<0.05). Additionally, with increase of future temperature, stratification strength of the reservoir is projected to be stronger, and the number of the days when temperature difference of the upper layer and the lower layer becomes greater than $5^{\circ}C$, also increase. Increase of water temperature on the surface of the reservoir, affected seasonal growth rate of the algae community. In particular, the growth rate of cyanobacteria increased in spring, and early summer.

• Journal of Animal Science and Technology
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• v.65 no.5
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• pp.895-911
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• 2023

Processed meat products play a vital role in our daily dietary intake due to their rich protein content and the inherent convenience they offer. However, they often contain synthetic additives and ingredients that may pose health risks when taken excessively. This review explores strategies to improve meat product quality, focusing on three key approaches: substituting synthetic additives, reducing the ingredients potentially harmful when overconsumed like salt and animal fat, and boosting nutritional value. To replace synthetic additives, natural sources like celery and beet powders, as well as atmospheric cold plasma treatment, have been considered. However, for phosphates, the use of organic alternatives is limited due to the low phosphate content in natural substances. Thus, dietary fiber has been used to replicate phosphate functions by enhancing water retention and emulsion stability in meat products. Reducing the excessive salt and animal fat has garnered attention. Plant polysaccharides interact with water, fat, and proteins, improving gel formation and water retention, and enabling the development of low-salt and low-fat products. Replacing saturated fats with vegetable oils is also an option, but it requires techniques like Pickering emulsion or encapsulation to maintain product quality. These strategies aim to reduce or replace synthetic additives and ingredients that can potentially harm health. Dietary fiber offers numerous health benefits, including gut health improvement, calorie reduction, and blood glucose and lipid level regulation. Natural plant extracts not only enhance oxidative stability but also reduce potential carcinogens as antioxidants. Controlling protein and lipid bioavailability is also considered, especially for specific consumer groups like infants, the elderly, and individuals engaged in physical training with dietary management. Future research should explore the full potential of dietary fiber, encompassing synthetic additive substitution, salt and animal fat reduction, and nutritional enhancement. Additionally, optimal sources and dosages of polysaccharides should be determined, considering their distinct properties in interactions with water, proteins, and fats. This holistic approach holds promise for improving meat product quality with minimal processing.

• Applied Chemistry for Engineering
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• v.35 no.2
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• pp.128-133
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• 2024

Although antisolvent-assisted crystallization is one of the promising processes to produce high-quality perovskite films, general antisolvents such as chlorobenzene (CB) have toxic and volatile properties. In addition, CB is not suitable to control the crystallization of perovskite in the atmospheric air. In this work, isopropyl acetate (IA) is used as an eco-friendly antisolvent to demonstrate air-processed perovskite solar cells, and ethyl-4-cyanocinnamate (E4CN) with a cyano group, carbonyl group, and aromatic ring is introduced in IA to improve the performance and stability of devices. Defects at the surface and grain boundaries of the perovskite layer, such as un-coordinated Pb²⁺ and iodine, can be decreased resulting from the interaction of E4CN and perovskite, and thus reduced recombination and enhanced carrier transport can be expected. As a result, the perovskite device with E4CN achieves a high maximum power conversion efficiency (PCE) of 18.89% and outstanding stability, maintaining 60% of the initial efficiency for 300 h in the air without any encapsulation.

• Atmosphere
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• v.20 no.4
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• pp.467-482
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• 2010

In this study, characteristics of various stability indexes (SI) and environmental parameters (EP) for the lightning are analysed by using 5 upper air observatories (Osan, Gwangju, Jeju, Pohang, and Baengnyeongdo) for the years 2002-2006 over South Korea. The analysed SI and EP are the lifted index, K-index, Showalter stability index, total precipitable water, mixing ratio, wind shear and temperature of lifting condensation level. The lightning data occurred on the range of -2 hr~+1 hr and within 100 km based on the launch time of rawinsonde and observing location are selected. In general, summer averaged temperature and mixing ratio of lower troposphere for the lightning cases are higher about 1 K and $1{\sim}2gkg^{-1}$ than no lightning cases, respectively. The Box-Whisker plot shows that the range of various SI and EP values for lightning and no lightning cases are well separated but overlapping of SI and EP values between lightning and no lightning are not a little. The optimized threshold values for the detection of lightning are determined objectively based on the highest Heidke skill socre (HSS), which is the most favorable validation parameter for the rare event, such as lightning, by using the simulation of SI and EP threshold values. Although the HSS is not high (0.15~0.30) and the number and values of selected SI and EP are dependent on geographic location, the new threshold values can be used as a supplementary tool for the detection or forecast of lightning over South Korea.

• Journal of Environmental Science International
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• v.17 no.6
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• pp.591-599
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• 2008

In order to support the development of wind farms in Jejudo, a wind resource database for Jejudo has been established using a meteor-statistical analysis of KIER(Korea Institute of Energy Research) met-mast measurements and KMA(Korea Meteorological Administration) weather data. The analysis included wind statistics, tower shading, an exposure category classification using satellite images, the effect of atmospheric stability on the wind profile exponent, and a correlation matrix of wind speed to gain an understanding of the meteorological correlation between long-term weather observation stations and short-term met-mast measurements. The wind resource database for Jejudo, is to be provided as an add-on to Google $Earth^{TM}$, which is expected to be utilized as a guideline for the selection of an appropriate reference site for long-term correction in the next wind farm development project.

• Journal of Korean Society of Forest Science
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• v.96 no.5
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• pp.602-608
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• 2007

Forest plantations become important strategy not merely for the financial aspect, but for carbon sequestration and ecosystem stability. Forest plantations increase the density of the forest biomass, which reduce the increase in atmospheric carbon dioxide. Biomass density is also a useful variable for comparing structural and functional attributes of forest ecosystems across a wide range of environmental conditions. In this study, carbon sequestration of teak (Tectona grandis Linn. f.) in the individual tree and plantation levels estimation was carried out Site-specific allometric equation for the estimation of teak tree biomass was developed based on the direct measurement of fifteen (15) harvested trees in the Oak-twin Township of the Bago Yoma Region, Myanmar. A regression equation of the diameter at breast height (DBH) and the aboveground biomass (carbon content) was constructed to estimate the carbon storage level of plantations, which averaged 79 ton/ha. The average carbon accumulation in the soil (up to 30 cm in depth) was estimated 38.89 ton/ha, The highest mean annual increment (MAI) of total carbon was found in the 6-yr-old teak plantation (12.10 ton/ha/yr) whereas the lowest MAI was in the 26-yr-old teak plantation (4.31 ton/ha/yr).

• Journal of the Korean Institute of Gas
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• v.1 no.1
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• pp.73-80
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• 1997

This study was performed to develop the dispersion modeling methodology for quantitative prediction of the hazard distance or toxic buffer distance by comparing 10-min average, 30-min average, and 1-hr average maximum ground-level concentration with $Cl_2$ regultaion concentration, IDLH and ERPG-3 concentration for hazardous toxic gas, $Cl_2$ releases from the storage tank of the chemical plant facilities. For this dispersion modeling, the source term model, dispersion model, meteorological and topographical data are incorporated into the SuperChems model, and then the effects of the atmospheric stability, wind speed, and surface roughness length changes on the maxum ground-level concentration were estimated.

• Journal of the Korean Society of Safety
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• v.29 no.5
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• pp.1-6
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• 2014

When the fluid energy convert into kinetic energy due to water hammer, the propagation velocity of pressure wave appear. The propagation velocity of pressure wave(1050 m/s) of very fast could be damage to the pipeline system. If the occurrence of water hammer is due to down-pressure, the faster the air exhaust or supply device is needed. it is high Speed Air Valve. In this paper, Each 3.12, 3.13, 3.72, $3.74kg/cm^2$ pipeline pressure were setting, and then executed pressure rapid drop for obtaining a high Speed Air Valve Operating time and pressure change data. the result was that pipe line pressure stabilization time were each 0.98, 1, 1.22, 1.25 sec. In other words, that pressure drop experimental results pipe line pressure was equal to atmospheric pressure without negative pressure After about one second. The study result would be useful to pipe line system stability design because this data could be foresee pressure stabilization time.

• Proceedings of the KSRS Conference
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• 2006.03a
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• pp.117-120
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• 2006

Heavy rainfall events are occurred exceedingly various forms by a complex interaction between synoptic, dynamic and atmospheric stability. As the results, quantitative precipitation forecast is extraordinary difficult because it happens locally in a short time and has a strong spatial and temporal variations. GOES-9 imagery data provides continuous observations of the clouds in time and space at the right resolution. In this study, an power-law type algorithm(KAE: Korea auto estimator) for estimating rainfall based on the rainfall type was developed using geostationary meteorological satellite data. GOES-9 imagery and automatic weather station(AWS) measurements data were used for the classification of rainfall types and the development of estimation algorithm. Subjective and objective classification of rainfall types using GOES-9 imagery data and AWS measurements data showed that most of heavy rainfalls are occurred by the convective and mired type. Statistical analysis between AWS rainfall and GOES-IR data according to the rainfall types showed that estimation of rainfall amount using satellite data could be possible only for the convective and mixed type rainfall. The quality of KAE in estimating the rainfall amount and rainfall area is similar or slightly superior to the National Environmental Satellite Data and Information Service's auto-estimator(NESDIS AE), especially for the multi cell convective and mixed type heavy rainfalls. Also the high estimated level is denoted on the mature stage as well as decaying stages of rainfall system.