• Journal of the Korean association of regional geographers
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• v.15 no.3
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• pp.337-350
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• 2009

The phenological change of plants is an indication of local and regional climate change. An increase in temperature due to global warming is manifest in the change of phytophenological events. In this study, trends in the plant phenology and its correlation with air temperature in South Korea were examined using observational data for 18 phenological phases. The spring phenological phases, such as sprouting and flowering, occurred earlier (from 0.7 to 2.7 days per 10-year) during 1945 ${\sim}$2007. while the autumn phases, such as full autumn tinting, moved later (from 3.7 to 4.2 days per 10-year) during 1989 ${\sim}$2007. The correlation between the plant phenology in spring with the air temperature from February to March is relatively high. The warming in the early spring (February March) by $1^{\circ}C$. causes an advance in the spring plant phenology of 3.8 days. The plant phenology in autumn also correlates with the average temperature in October. The autumn plant phenology for a $1^{\circ}C$ increase in October temperature occurs about 3.1 days later.

• Structural Engineering and Mechanics
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• v.68 no.5
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• pp.519-526
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• 2018

In this article, experimental training of the commercial available shape memory alloy fibre (SMA) fibre under the combined thermomechanical loading is reported. SMA has the ability to sense a small change in temperature (${\geq}10^{\circ}C$) and activated under the external loading and results in shape change. The thermomechanical characteristics of SMA at different temperature and mechanical loading are obtained through an own lab-scale experimental setup. The analysis is conducted for two types of the medium using the liquid nitrogen (cold cycle) and the hot water (heat cycle). The experimental data indicate that SMA act as a normal wire for Martensite phase and activated behavior i.e., regain the original shape during the Austenite phase only. To improve the confidence of such kind of behavior has been verified by inspecting the composition of the wire. The study reveals interesting conclusion i.e., while SMA deviates from the equiatomic structure or consist of foreign materials (carbon and oxygen) except nickel and titanium may affect the phase transformation temperature which shifted the activation phase temperature. Also, the grain structure distortion of SMA wire has been examined via the scanning electron microscope after the thermomechanical cycle loading and discussed in details.

• KIEAE Journal
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• v.12 no.3
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• pp.53-60
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• 2012

This research is an illustrative research to verify the thermo environmental change created after introduction of indoor pond through abridged model test and simulation analysis. Especially, temperature and comfort level are analyzed by adjusting factors like size of water space, distance length, and location. Summary of the research is as follows. First, the most effective size of water space is 7% of the indoor size, from southern side. Temperature reduction effect is about $1.6^{\circ}C$(5.5%), and for the comfort level, it is found that pmv index increases 8%. Second, based on the simulation of distance length with the sphere, it is more effective as it is close to the surface. If distance length is more than 0.5m, there is no effect on reduction of temperature and comfort level of indoor environment. Lastly, for the analysis by location of the introduced water space, simulation is undertaken by dividing the water space (14% of the indoor size) with front, side, rear and center types. Temperature reduction effect is found to be : front type ($-1.53^{\circ}C$), side type ($-0.82^{\circ}C$), rear type ($-0.44^{\circ}C$), center type ($-0.28^{\circ}C$), respectively. The indoor environment change data by introduction of water space, found in this research, is at initial phase, but it is deemed to be a basic data to refer when planning actual water space.

• Economic and Environmental Geology
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• v.39 no.1 s.176
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• pp.95-102
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• 2006

To properly interpret and define climatic warming trends of the last $100\~150$ years.; climatic changes over the past several centuries must be constrained. High resolution surface air temperatures (SATs) to reconstruct global temperature trends extend back only to the late of 19th century. Fortunately, on long time scale and over large areas, ground surface temperatures (GSTs) track SATs. GST changes penetrate into the subsurface and are recorded as transient temperature perturbation. Therefore, borehole temperatures can be used to recover climate change over the last millennium in an area; paleoclimate change inferred from borehole temperatures can be used to interpret global warming over the last century, little ice age, and medieval warm period.

• Journal of the Korean Chemical Society
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• v.34 no.6
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• pp.548-554
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• 1990

Temperature effects on the fluorescence emission spectra of 0.01 M Eu(III) ion with ClO$_4$, Cl$^-$, NO$_3$ were studied. Relative intensity change of hypersensitive band ($^5D0\; {\to}\;^7F_2$) and nonhypersensitive band ($^5D0 \;{\to}\;^7F_1$) was quite remarkable with temperature and ligand. The relative intensity change was interpreted as the change of formation constant and used to calculation the enthalpy change of $Eu(H_2O)_X^{3+}$+ to EuL(H$_2O)_{X-1}^{2+}$ complex. $\Delta{H}$ of $Eu(H_2O)_X^{3+}$ to EuCl(H$_2O)_{X-1}^{2+}$ was roughly 15 kJ/mol and temperature independent, but $\Delta{H}$ of EuNO$_3(H_2O)_{X-1}^{2+}$ was changed with temperature; -11 kJ/mol at 25$^{\circ}C$ and 47 kJ/mol at 250$^{\circ}C$.

• Korean Journal of Environmental Agriculture
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• v.27 no.4
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• pp.456-459
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• 2008

Quality of rice grain changes during dry storage with internal physiological changes and external injury by organism. Storage rice changes by condition with respiration via variable temperature, hydrolysis enzyme reaction, lipid peroxidation occurs with change of palatability. During dry storage, physiological change with protein variation pattern was examined by image analysis on proteomic technology. Analysis revealed that protein activity had no change store at room temperature and store at $40^{\circ}C$, but decreased store at $60^{\circ}C$. Analysis of variable hydrophobic protein pattern revealed that protein activity of beta-tubulin, protein disulfide isomerase, vacuolar ATPase b subunit, globulin was not significantly decreased all dry and store condition. However, heat shock protein 70, and glutathione transferase was significantly decreased when rice dried at $60^{\circ}C$ compared with room temperature and $40^{\circ}C$ dry condition.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.11
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• pp.17-22
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• 2005

In this study, we suggested wave-variable Bragg lattice using the characteristic of the Bragg wave that varies according to the change of the temperature imposed on the optical fiber lattice device, and experimented using a simulation test. We analyzed the results of the FBG change according to the change of the temperature obtained in the variable FEG computer simulation and experiment to suggest optimal data. Therefore, utilizing wave-variable optical filter through FBG allows us to combine other channels beyond optical fiber lattice device wave, and can be used as a helpful device in the Dense Wavelength Division Multiplexed system with a channel intervention of 0.08nm(10GHz).

• Journal of Climate Change Research
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• v.2 no.2
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• pp.133-141
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• 2011

This study is to identify the trend of climate change in Gangwon-do by examining accumulated climate data such as temperature and precipitation in Gangneung city over the past about 100 years. The annual mean temperature and precipitation in Gangneung have increased by $1.4^{\circ}C$ and 14.7%, respectively, over the last 98 years (1912~2009). The trends of Gangneung showed that precipitation has intensified as the number of precipitation days decreased while its amount increased during the period. Based on the temperature data, spring and summer began earlier whereas the onsets of fall and winter were delayed. Summer has become longer and winter shorter by about a month. Averaging observation data from seven weather stations in Gangwon-do, the annual mean temperature and precipitation have increased by $0.8^{\circ}C$ and 21.0% respectively over the last 37 years (1973~2009). By region, Wonju city recorded the biggest increase of $1.6^{\circ}C$ in the annual mean temperature while Sokcho city the smallest increase of $0.4^{\circ}C$. In the annual mean precipitation, Daegwallweong recorded the biggest change of 22.2% and Wonju city the smallest of 12.0%.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.4
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• pp.405-414
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• 2021

This study predicted waxy corn harvest date in South Korea using 30-year (1991-2020) hindcasts (1-6 month lead) produced by the Pusan National University Coupled General Circulation Model (PNU CGCM)-Weather Research and Forecasting (WRF) chain. To estimate corn harvest date, the cumulative temperature is used, which accumulated the daily observed and predicted temperatures from the seeding date (5 April) to the reference temperature (1,650~2,200℃) for harvest. In terms of the mean air temperature, the hindcasts with a bias correction (20.2℃) tends to have a cold bias of about 0.1℃ for the 6 months (April to September) compared to the observation (20.3℃). The harvest date derived from bias-corrected hindcasts (DOY 187~210) well simulates one from observation (DOY 188~211), despite a slight margin of 1.1~1.3 days. The study shows the possibility of obtaining the gridded (5 km) daily temperature and corn harvest date information based on the cumulative temperature in advance for all regions of South Korea.

• Journal of the Korea Safety Management & Science
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• v.15 no.4
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• pp.97-103
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• 2013

The purpose of this study was to verify the change in temperature humidity perspiration of fire suit when applying phased intensive exercises to fire fighter wearing fire suit. For this study, three male fire fighters took basic physical test and performed 10 minute phased intensive exercises -exercise intensity I (30%VO2max), exercise intensity II (45%VO2max), exercise intensity III (60%VO2max) based on maximum oxygen consumption (VO2max)- wearing fire suit (helmet, boots, air respirator) in treadmill and took a rest. The result of study shows that the temperature in the suit elevated during stabilization period after each exercise intensity, humidity elevated as exercise intensity increased, perspiration elevated as exercise intensity increased. This study indirectly ascertained the fire suit's physiological change in fire fighters during field activities.