• Atmosphere
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• v.32 no.4
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• pp.395-409
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• 2022

A new soil moisture initialization scheme is applied to the Korea Meteorological Administration (KMA) Global Seasonal forecasting system version 6 (GloSea6). It is designed to ingest the microwave soil moisture retrievals from Soil Moisture Active Passive (SMAP) radiometer using the Local Ensemble Transform Kalman Filter (LETKF). In this technical note, we describe the procedure of the newly-adopted initialization scheme, the change of soil moisture states by assimilation, and the forecast skill differences for the surface temperature and precipitation by GloSea6 simulation from two preliminary experiments. Based on a 4-year analysis experiment, the soil moisture from the land-surface model of current operational GloSea6 is found to be drier generally comparing to SMAP observation. LETKF data assimilation shows a tendency toward being wet globally, especially in arid area such as deserts and Tibetan Plateau. Also, it increases soil moisture analysis increments in most soil levels of wetness in land than current operation. The other experiment of GloSea6 forecast with application of the new initialization system for the heat wave case in 2020 summer shows that the memory of soil moisture anomalies obtained by the new initialization system is persistent throughout the entire forecast period of three months. However, averaged forecast improvements are not substantial and mixed over Eurasia during the period of forecast: forecast skill for the precipitation improved slightly but for the surface air temperature rather degraded. Our preliminary results suggest that additional elaborate developments in the soil moisture initialization are still required to improve overall forecast skills.

• Journal of The Korean Society of Integrative Medicine
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• v.8 no.4
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• pp.191-202
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• 2020

Purpose : The purpose of this study is to examine the effect of the segmental mobilization technique of the lower back on the characteristics of the muscles and limited of stability of chronic backache patients. Methods : The subjects of the study were 30 chronic back pain patients who were divided into groups of 15, a manual therapy group (Group I) and a spinal decompression therapy group (Group II), via random assignation. The subjects had 15 minutes of superficial heat therapy, 15 minutes of interference wave therapy, and 5 minutes of ultrasound therapy for conservative physical therapy. Additionally, manual therapy and spinal decompression therapy were administered to each group for 30 minutes, 5 times a week for 8 weeks. Before intervention, the characteristics of the muscles and limited of stability of the muscles were analyzed. After 8 weeks of intervention, the above items were re-measured in the same manner and analyzed between groups. Results : The results of comparative analysis of the characteristics of the muscles and limited of stability between groups showed that there were statistically significant differences. The manual therapy group (Group I) showed significant differences in characteristics of the muscles compared to the spinal decompression therapy group (Group II). The manual therapy group (Group I) showed significant differences in limited of stability compared to the spinal decompression therapy group (Group II). Conclusion : The result confirmed that manual therapy was more effective in the characteristics of the muscles and limited of stability. Based on this study, additional studies are necessary on the effect of various techniques of manual therapy on muscle activity and muscle thickness in chronic back pain patients. In order to develop an effective manual therapy program, studies using a variety of evaluations are needed.

• Journal of Korean Library and Information Science Society
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• v.53 no.2
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• pp.333-353
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• 2022

This study analyzed the relevance of the curriculum by applying topic modeling to book reports written as content area reading activities in the 'physics' class. In order to carry out the research, 332 physics book reports were collected to analyze the relevance among keywords and topics were extracted using STM. The result of the analysis showed that the main keywords of the physics book reports were 'thought', 'content', 'explain', 'theory', 'person', 'understanding'. To examine the influence and connection relationship of the derived keywords, the study presented degree centrality, between centrality, and eigenvetor centrality. As a result of the topic modeling analysis, eleven topics related to the physics curriculum were extracted, and the curriculum linkage could be drawn in three subjects (Physics I, Physics II, Science History), and six areas (force and motion, modern physics, wave, heat and energy, Western science history, and What is science). The analyzed results can be used as evidence for a more systematic implementation of content area reading activities which reflect the subject characteristics in the future.

• Composites Research
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• v.21 no.2
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• pp.31-35
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• 2008

In order to design light weight and high efficient electromagnetic wave absorbing materials, hollow magnetic particles have been introduced in this study. The electroless plating method has been utilized to coat Ni and Fe on the substrates of synthesized polystyrene particles of submicron size. Removing polystyrene particles by heat treatment resulted in hollow structures. Observation by SEM, TEM and EDS confirmed the surface morphology and coating thickness of Ni and Fe. Polymeric composites containing hollow particles were tested in order to compare the electromagnetic properties between Ni coated and Fe costed particles. The composite of 30 wt% Fe hollow particles showed the higher complex permeability than Ni hollow particles or the conventional barium ferrite particles.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.6
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• pp.1049-1056
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• 2023

The height of the atmospheric boundary layer indicates the peak developed when turbulence is generated by mixing heat and water vapor, and is generally determined through thermodynamic methods. Wind profilers produce atmospheric information from the scattering of signals sent into the atmosphere. A method for making the spectrum of turbulent components, turbulent kinetic energy dissipation rate, and refractive index structure coefficient was presented to determine the atmospheric boundary layer depth. Compared with the vertical distribution characteristics of potential temperature and specific humidity based on radiosonde data, the determination method of the atmospheric boundary layer height from wind profiler output was evaluated as very useful.

• Tunnel and Underground Space
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• v.21 no.1
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• pp.33-40
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• 2011

This study focuses on having a temperature and water pressure effects on the change of material properties of rocks. Granite and limestone specimens from Gagok Mine were thermally treated with predetermined temperatures of 200, 300, 400, 500, 600 and $700^{\circ}C$ (excepting $700^{\circ}C$ for limestone) to estimate the reduction of material properties of rocks caused by heat. Specific gravity, effective porosity, elastic wave velocity, uniaxial compressive strength, Young's modulus and Poisson's ratio for pre-heated specimens were measured. With increasing temperature, material properties of both rock specimens change sequentially. Significant changes of specific gravity, effective porosity and elastic wave porosity occur above $400^{\circ}C$ for granite and $300^{\circ}C$ for limestone. Changes of uniaxial compressive strength, Young's modulus and Poisson's ratio seem to be similar to those of physical properties. GSI of 500, 600 and $700^{\circ}C$ specimens inferred by using uniaxial compressive strength and Young's modulus of preheated granite specimens is found to be 81, 66 and 58 each. In case of pre-heated limestone specimens of 400, 500 and $600^{\circ}C$, the corresponding GSI is 76, 71 and 65 each. 500, 600 and $700^{\circ}C$ granite specimens and 400, 500 and $600^{\circ}C$ limestone specimens were pressurized to 7.5 MPa and their effective porosity, elastic wave velocity, uniaxial compressive strength and Young's modulus were measured. The average value of material properties (mentioned above) of 500, 600 and $700^{\circ}C$ granite specimens under water pressure compared with material properties of non-pressurized pre-heated specimens exhibits the reduction of 7.6, 11.3 and 14.9%, respectively. In case of 400, 500 and $600^{\circ}C$ limestone specimens under water pressure, the average value of material properties decreases by 8.2, 13.8 and 21.9%, respectively.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.6
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• pp.115-125
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• 2017

This study was to investigate the user's thermal environments under the pergola($L\;7,200{\times}W\;4,200{\times}H\;2,700mn$) covered with Wisteria floribunda(Willd.) DC. according to the variation of leaf area index(LAI). We carried out detailed measurements with two human-biometeorological stations on a popular square Jinju, Korea($N35^{\circ}10^{\prime}59.8^{{\prime}{\prime}}$, $E\;128^{\circ}05^{\prime}32.0^{{\prime}{\prime}}$, elevation: 38m). One of the stations stood under a pergola, while the other in the sun. The measurement spots were instrumented with microclimate monitoring stations to continuously measure air temperature and relative humidity, wind speed, shortwave and longwave radiation from the six cardinal directions at the height of 0.6m so as to calculate the Universal Thermal Climate Index(UTCI) from $9^{th}$ April to $27^{th}$ September 2017. The LAI was measured using the LAI-2200C Plant Canopy Analyzer. The analysis results of 18 day's 1 minute term human-biometeorological data absorbed by a man in sitting position from 10am to 4pm showed the following. During the whole observation period, daily average air temperatures under the pergola were respectively $0.7{\sim}2.3^{\circ}C$ lower compared with those in the sun, daily average wind speed and relative humidity under the pergola were respectively 0.17~0.38m/s and 0.4~3.1% higher compared with those in the sun. There was significant relationship in LAI, Julian day number and were expressed in the equation $y=-0.0004x^2+0.1719x-11.765(R^2=0.9897)$. The average $T_{mrt}$ under the pergola were $11.9{\sim}25.4^{\circ}C$ lower and maximum ${\Delta}T_{mrt}$ under the pergola were $24.1{\sim}30.2^{\circ}C$ when compared with those in the sun. There was significant relationship in LAI, reduction ratio(%) of daily average $T_{mrt}$ compared with those in the sun and was expressed in the equation $y=0.0678{\ln}(x)+0.3036(R^2=0.9454)$. The average UTCI under the pergola were $4.1{\sim}8.3^{\circ}C$ lower and maximum ${\Delta}UTCI$ under the pergola were $7.8{\sim}10.2^{\circ}C$ when compared with those in the sun. There was significant relationship in LAI, reduction ratio(%) of daily average UTCI compared with those in the sun and were expressed in the equation $y=0.0322{\ln}(x)+0.1538(R^2=0.8946)$. The shading by the pergola covered with vines was very effective for reducing daytime UTCI absorbed by a man in sitting position at summer largely through a reduction in mean radiant temperature from sun protection, lowering thermal stress from very strong(UTCI >$38^{\circ}C$) and strong(UTCI >$32^{\circ}C$) down to strong(UTCI >$32^{\circ}C$) and moderate(UTCI >$26^{\circ}C$). Therefore the pergola covered with vines used for shading outdoor spaces is essential to mitigate heat stress and can create better human thermal comfort especially in cities during summer. But the thermal environments under the pergola covered with vines during the heat wave supposed to user "very strong heat stress(UTCI>$38^{\circ}C$)". Therefore users must restrain themselves from outdoor activities during the heat waves.

• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.2
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• pp.1-23
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• 2018

This study aims to propose a way for evaluating thermal environment vulnerability associated with policy to improve thermal environment. For this purpose, a variety of indices concerning thermal vulnerability assessment and adaptation policies for climate change applied to 17 Korean cities were reviewed and examined. Finally, 15 indices associated with policies for improving thermal environment were selected. The selected indices for thermal vulnerability assessment were applied to Daegu Metropolitan City of South Korea as a case study. As results, 15 vulnerability maps based on the standardized indices were established, and a comprehensive map with four grades of thermal vulnerability were established for Daegu Metropolitan City. As results, the area with the highest rated area in the first-grade(most vulnerable to heat) was Dong-gu, followed by Dalseo-gu and Buk-gu, and the highest area ratio of the first-grade regions was Ansim-1-dong in Dong-gu. Based on the standardized indices, the causes of the thermal environment vulnerability of Ansim-1-dong were accounted for the number of basic livelihood security recipients, the number of cardiovascular disease deaths, heat index, and Earth's surface temperature. To improve the thermal environment vulnerability of Ansim-1-dong, active policy implementation is required in expansion and maintenance of heat wave shelters, establishment of database for the population with diseases susceptible to high temperature environments, expansion of shade areas and so on. This study shows the applicability of the vulnerability assessment method linked with the policies and is expected to contribute to the strategic and effective establishment of thermal environment policies in urban master district plans.

• Journal of the Korean Association of Geographic Information Studies
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• v.26 no.2
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• pp.68-81
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• 2023

This study aims to establish a scenario based on the spacing and arrangement of the roadside trees to reduce heat waves and fine dust in cities that occurred during the urbanization process and to quantitatively analyze the degree of reduction. The ENVI-met 5.0.2v model, a micro-climate simulation program, was used to analyze the degree of improvement in the thermal environment and fine dust according to the roadside tree scenario. As a result of temperature analysis according to street tree spacing, the narrower the distance between roadside trees, the lower the temperature during the day as the number of planted trees increased, and a similar pattern was shown regardless of the distance between roadside trees in the morning and evening. In the case of fine dust emitted from the road, the concentration of fine dust increased slightly due to the increase in roadside trees, but the concentration of sidewalks where people walk increased slightly or there was no difference because of blocking fine dust on trees. The temperature according to the arrangement of street trees tended to decrease as the number of planted trees increased as the arrangement increased. However, not only the amount of trees but also the crown projected area was judged to have a significant impact on the temperature reduction because the temperature reduction was greater in the scenario of planting the same amount of trees and widening the interval of arrangement. In terms of the arrangement, the fine dust concentration showed a difference from the results according to the interval, suggesting that the fine dust concentration may change depending on the relationship between the main wind direction and the tree planting direction. By quantitatively analyzing the degree of thermal environment and fine dust improvement caused by roadside trees, this study is expected to promote policies and projects to improve the roadside environment efficiently, such as a basic plan for roadside trees and a project for wind corridor forests.

• Korean Journal of Heritage: History & Science
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• v.55 no.4
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• pp.212-240
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• 2022

This study is a multi-layered exploration of 「The Thirty-Six Scenery of Seongdeok Summer Mountain Resort(承德避暑山莊三十六景)」 (The 36th view of Kangxi) recited by Emperor Kangxi of China through literature study, ancient calligraphy diagrams, and field studies. The conclusion of tracing the landscape characteristics and implications contained in 「The 36th view of Kangxi」 through the analysis of the headword(標題語) and the interpretation of the Jeyeong poem(題詠詩) is as follows. 「The 36th view of Kangxi」 is an extension of the outer edge of the Eight Sceneries, and when compared to the existing Eight Sceneries peom and Eight Sceneries painting, it is found that the landscape is centered on the 'viewpoint' rather than the landscape object. In particular, it aimed to create a structured landscape centered on nine types of buildings represented by 'Jeon(殿)' and 'Jeong(亭)' was given. In particular, Yeouiju, located in Lake district, is a scenic country endowed with the character of a gardens in Garden, which is composed by collecting famous representative Chinese landscapes and landscapes of Sansu-si and Sanshu Painting. As a result of headword analysis to understand the characteristics of landscape components, 14 landscapes (38.9%) related to water elements and 13 landscapes(36.1%) related to mountain elements, the elements related to architecture and civil engineering were classified in the order of 3 cases(8.3%), and the elements related to the skylight were classified in the order of 2 cases(5.6%). However, in Jeyeong-si, the mention of landscape vocabulary for climate elements was overwhelming. In other words, in the poems of 「The 36th Scenery of Kangxi」, scenery vocabulary symbolizing 'coolness' such as 雲(cloud), 水(water), 泉(spring), 清(clear), 波(wave), 流(wave), 風(wind) and 無暑(without heat), etc. It is not a coincidence that it appears, and it is strongly attached to the sense of place of Summer Mountain Resort in Rehe(熱河). Among the 23 landscapes whose seasonal background was confirmed, the fact that the lower landscape is portrayed as the majority and the climate elements of the resort area are portrayed in three-dimensional and multi-dimensional ways are closely related to the period of enjoying the gardens of Kangxi, the main subject of the landscape. In addition, many animal and plant landscapes appearing in Jeyeong-si appear to be in the same context as the spatial attributes of not only recreation, but also contemplation and hunting. On the other hand, in Jeyeongsi, there are 33 wonders(91.7%) citing famous people and famous books through ancient poems, old stories, and ancient stories tends to be prominent. It is inferred that this was based on Kangxi's understanding and pride in traditional Chinese culture. In 「The 36th view of Kangxi」, not only a book-writing description of the feelings of being entrusted to the family sutras, but also the spirit of patriotism, love, self-discipline and respect for mother and filial piety are strongly implied. Ultimately, 「The 36th view of Kangxi」 shows the real scene of the resort, as well as the spiritual dimension, in a multi-faceted and three-dimensional way, and the spirit of an emperor based on the dignity of the royal family and the sentiments of a writer it deserves to be called a collection of imperial records that were intended to reveal.