• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.47.2-47.2
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• 2017

We investigate the environmental effects on galaxy spin using the sample of ~1100 galaxies from the first public data of MaNGA integral field unit survey. We determine the spin parameter ${\lambda}_{Re}$ of galaxies by analyzing the two-dimensional stellar kinematic measurements within the effective radius, and study its dependence on the large-scale (background mass density determined with 20 nearby galaxies) and small-scale (distance to and morphology of the nearest neighbor galaxy) environments. We first examine the mass dependence of galaxy spin, and find that the spin parameter decreases with stellar mass at log ($M_{\ast}/M_{\odot}$) > 10, consistent with previous studies. We then divide the galaxies into three subsamples using their stellar masses to minimize the mass effects on galaxy spin. The spin parameter of galaxies in each subsample does not change with the background density, but do change with the distance to and morphology of the nearest neighbor. The spin parameter increases when late-type neighbors are within the virial radius, and decreases when early-type neighbors are within the virial radius. These results suggest that the large-scale environments hardly affect the galaxy spin, but the effects of small-scale environments such as hydrodynamic galaxy-galaxy interactions are substantial.

• Journal of Industrial Technology
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• v.30 no.A
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• pp.119-126
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• 2010

The special characters of traditional architecture has been formed suitably correspond with the purpose of usage and function, which was influenced with various environmental factors such as natural, social, physical, cultural and thoughtful. There was some differences in building placement and space composition according to the regional character such as climate, customs, and a gap of convention (long-established custom) and one's social position system and custom character of family. However, the essential characteristic of traditional architecture are nicely contain the era's architectural character. But these characters are developed or extinct according to the environmental factors. This paper is looking for the elements that formed social cultural element and background architect's thought. And, with the historical background, there are looking for Occupation. A traditional architecture had been formed correspond with the purpose of usage and function, which was influenced with physical nature environment elements such as regional character, climate, customs and social cultural environment elements such as government, economy, society, culture and thoughtful elements.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.11 no.1
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• pp.39-51
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• 2008

These days, one of the issues well discussed is the obstruction or screen of sight to mountain-skyline by buildings. So question is to which heights buildings should be constructed over mountain-skyline and then harmony can be realized between mountain-skyline and building-outline. Based on the mentioned above, this study intends to find out the proper projection- level of buildings over background mountain-skyline when considering the types of mountain-skyline, building-outline and building-layout. The results of this study are first, the proper projection-ratio of buildings over background mountain-skyline can be 0.1 because assessment values on harmony-level are more than 3.0 in almost cases, second, the building-outline influences on the assessment values of harmony-level when the types of mountain-skyline are formed left-high & right-low and right-high & left-low, third, building-layout doesn't influence on the assessment va lues of harmony-level, finally, statistically difference doesn't exist between expert group and non-expert group in the assessment values of harmony-level.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.1
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• pp.15-24
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• 2014

It is essential to understand the infrared signature of a naval ship to survive against various missile attacks under variable environmental conditions. As guided missiles are developing to equip more accurate IR seekers, research works for countermeasure and IR stealth technology are strongly required. But challenging works are continuously suggested for predicting and analyzing IR signal status of naval ships to achieve low observable performance under various weather conditions, variable missions and developing threats. In this study, overall guidelines of setting design criteria for low observable ships are proposed by considering varying environmental conditions including daily and seasonal variations. Test and evaluation criteria for newly constructed ships for target and background temperature difference is proposed as a design criteria which can be predicted by change of condition and ship's speed. Through the proposed techniques and procedures, it is expected to establish the measurement and evaluation criteria by using temperature, IR Signal differences between the ship and the background.

• Journal of Wetlands Research
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• v.25 no.1
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• pp.48-63
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• 2023

Research on the method of calculating and estimating evapotranspiration has been steadily conducted. Various models have been developed according to different backgrounds, and each of these models has different characteristics such as required input data. Therefore, this study introduces the theoretical background and characteristics of evapotranspiration models and the development process of domestic research on evapotranspiration by era. First, the origin and theoretical background of the potential evapotranspiration models are summarized in addition to classifying them by input data. Then, the characteristics of the actual evapotranspiration estimation methods are summarized. Additionally, methods based on observation and methods using the rainfall-runoff models are summarized.

• Journal of Korean Society for Atmospheric Environment
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• v.33 no.6
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• pp.616-625
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• 2017

Measurements using five real-time particle samplers were compared to measurements using three NRM (National Reference Method system) filter-based samplers(Gravimetric method) at Incheon, Korea, between May and August, 2014. The purpose of this study was to suggest the quality assurance/quality control (QA/QC) method of each instrument for use in a real-time continuous particle sampler to measure the mass of airborne particles with an aerodynamic diameter less than $2.5{\mu}m$ ($PM_{2.5}$). Five real-time particle samplers of BAM1020, FH62C_14, TEOM, PM-711 and SPM-613 were evaluated by comparing its measured 23 hr average $PM_{2.5}$ concentrations with those measured with NRM filter-based samplers simultaneously. The parameters(e.g. Inlet heating condition, Slope factor, Film response, Intercept, Background, Span value) of the real-time samplers were optimized respectively by conducting test performance evaluation during 7 days in field sampling. For example, inlet heating temperature of TEOM sampler controls $35{\sim}40^{\circ}C$ to minimize the fluctuation of the real-time measurement data and background value of BAM1020 is the key factor affecting the accuracy of $PM_{2.5}$ mass concentration. We classified the $PM_{2.5}$ concentration according to relative humidity (80%) to identify water absorbed in aerosols by measuring the ${\beta}$-ray samplers(BAM1020, FH62C_14) and TEOM. ${\beta}$-ray samplers were not strongly affected by relative humidity that the difference of the average $PM_{2.5}$ concentration was about 5%. On the other hand, The TEOM sampler overestimated $PM_{2.5}$ mass concentration about 15% at low relative humidity (<80%).

• Journal of Ecology and Environment
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• v.43 no.2
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• pp.212-218
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• 2019

Background: Allelopathy has been suggested as one potential mechanism facilitating the successful colonisation and expansion of invasive plants. The impacts of the ongoing elevation in atmospheric carbon dioxide (CO₂) on the production of allelochemicals by invasive species are of great importance because they play a potential role in promoting biological invasion at the global scale. Common ragweed (Ambrosia artemisiifolia var. elatior), one of the most notorious invasive exotic plant species, was used to assess changes in foliar mono- and sesquiterpene production in response to CO₂ elevation (389.12 ± 2.55 vs. 802.08 ± 2.69 ppm). Results: The plant growth of common ragweed significantly increased in elevated CO₂. The major monoterpenes in the essential oil extracted from common ragweed leaves were β-myrcene, DL-limonene and 1,3,6-octatriene, and the major sesquiterpenes were β-caryophyllene and germacrene-D. The concentrations of 1,3,6-octatriene (258%) and β-caryophyllene (421%) significantly increased with CO₂ elevation. Conclusions: These findings improve our understanding of how allelochemicals in common ragweed respond to CO₂ elevation.

• Journal of the Korean housing association
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• v.19 no.3
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• pp.1-10
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• 2008

When environmental elements such as heat, light, air, and sound conditions were suited for the human life, it makes for the welfare and comfortableness of dwellers. This study about residential environmental stress based on environmental psychology very importance because dwellers' background characteristics have an impact on their residential environmental stress levels and it was related to dwellers' satisfaction and well-being. Research about stress connected with residential environment is very important. One's residential environment has direct effects not only on the physical environment but also on family values and expectations, actions, attitude etc. The purpose of this paper is to: 1) identify the general trends of residential environmental stress 2) analyze the differences in socio-demographic characteristics and how the physical characteristics of buildings affect stress. The samples in this study consisted of dwellers living in multi-family housing in Gwang-ju, South Korea. The city was divided into 5 districts and used quota sampling. 324 housewives were sampled from the households by self-administered questionnaires. The survey was conducted in December of the year 2006 after the questionnaire was revised based on the results of preliminary survey.

• Journal of the Korean Home Economics Association
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• v.42 no.1
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• pp.1-16
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• 2004

The purpose of this study is to understand the relationship between the environmental movement and voluntary simplicity life style. The results of this study are as follows： First, both voluntary simplicity life style and the environmental movement are concepts which became the center of public interest because of the evil practices appeared in the process of the development of capitalism. Second, the level of consciousness of environment is comparatively high, but the level of the power of execution is comparatively low as a whole. In the case of Korea, people have not yet the mature responsibilities of citizenship. It is very important to enforce different informal educations in order to increase the effectiveness of the environmental movement. Home training based on voluntary simplicity life style is the most important informal education for the purpose of increasing the effectiveness of the environmental movement. Consequently, for the preservation of environment we need to do our best endeavors such as home training based on voluntary simplicity life style, environmental education based on our social and cultural background, and more powerful administrative measures which is administrative support rather than administrative control.

• Journal of Ecology and Environment
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• v.43 no.1
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• pp.14-21
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• 2019

Background: Stoichiometry plays an important role in understanding nutrient composition and cycling processes in aquatic ecosystems. Previous studies have considered C:N:P ratios constant for both DOM (dissolved organic matter) and POM (particulate organic matter). In this study, water samples were collected in the six major rivers in Korea and were incubated for 20 days. C:N:P ratios were determined during the time course of the incubations. This allowed us to examine the changes in N and P contents of organic matter during decomposition. Results: POM and DOM showed significant differences in N and P content and the elemental ratios changed during the course of decomposition; DOM showed higher C:N and C:P ratios than POM, and the C:N and C:P ratios increased during decomposition, indicating the preferential mineralization of P over N and N over C. Conclusions: The N and P contents of organic matter in aquatic ecosystem are far from constant and vary significantly during decomposition. More detailed information on the changes in C:N:P ratios will provide improved understanding of decomposition processes and improved modeling of aquatic ecosystems.