• Ocean and Polar Research
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• v.28 no.4
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• pp.369-383
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• 2006

The Saemangeum project is one of the biggest reclamation efforts in Korea and may cause coastal ecosystem change due to altered environments and habitat loss. Since February 2002, benthic environment and community structure in the Saemangeum studied area were studied to assess the influence of the project on macrofaunal community. The result of seasonal study from February, 2002 to August 2005 is reported here. Overall, changes of species numbers and dominant species of benthic animals in the periods before (1988) and after $(2002{\sim}2005)$ the Saemangeum dike construction were not evident both inside and outside the dike. However, local environmental and community change were noted The partial completion of Saemangeum dike $(4^{th}\;dike)$ in June 2003 altered water circulation and sediment deposition patterns both inside and outside the dike. Fine sediment was accumulated inside and outside the $4^{th}$ dike while coarse sediment dominated near the main channel (Sinsi gate). Benthic community resl)ended to the altered sediment type in these areas. Species number and diversity in both site was low compared to other sites. The dominant species in these areas were composed of the benthos that had not commonly occurred in the Saemangeum subtidal area.

• Journal of the Korean Institute of Rural Architecture
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• v.11 no.1
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• pp.57-66
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• 2009

The purpose of this study is to suggest some ways for the development of rural agricultural area to head. For the purpose, this study analyzed residents' participation in the project and their satisfaction on the change of villages, in consideration with the type of village and its socio-demographic variables. The 101 residents of the 4 villages in Yeoju-gun, Gyeonggi-do, responded the questionnaire. The results are as follows. 1) The most important objective of the development project, responded residents, was to expand sales channel of agricultural products and find profitable vegetation, and they participated in it with eager. The residents, however, showed passive participation in the cleaning, planting and reforming in village. 2) The satisfaction level with the development project averaged 3.09 of 5 in the natural environment, 3.05 of 5 in the spatial environment, 2.58 of 5 in the economic environment, and 3.13 of 5 in the social environment. In every aspect, centralized villages showed more satisfaction than scattered villages, ages of under 60 were more satisfied than over 60, and over high school graduates answered more satisfied than under middle school graduates.

• KIEAE Journal
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• v.16 no.6
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• pp.135-142
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• 2016

Purpose: The purposes of this paper are to investigate effects of indoor thermal environment on acoustical perception and effects of acoustics on indoor thermal perception, and to understand basic human perception on indoor environment. Method: Subjective assessment was performed in an indoor environmental chamber with 24 university students. Thermal conditions with PMV -1.53, 0.03, 1.53, 1.83 were simulated with a VRF system, a humidifier, a dehumidifier, and a ventilation system. Six noise sources - Cafe, Fan, Traffic, Birds, Music, Water- with sound levels of 45, 50, 55, 60 dBA were played for 2 minutes in random order. Temperature sensation, temperature preference, humidity sensation, humidity preference, noisiness, loudness, annoyance, and acoustic preference were assessed using bipolar visual analogue scales. The ANOVA and Turkey's post hoc test were used for data analysis. Result: Thermal environmental perceptions were not altered through 2 minutes noise exposure. Acoustical perceptions were altered by thermal conditions. The results were consistent with previous papers, however, the noise exposure time should be carefully considered for further development.

• Resources Recycling
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• v.15 no.3 s.71
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• pp.81-86
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• 2006

Altered Langmuir adsorption isotherm has been suggested for adsorption reactions occurring in aqueous environment based upon the concept of the steric displacement between adsorbates and water molecules at the surface of adsorbent. For the adsorption of $Cd^{2+}$ on activated carbon, the suggested adsorption isotherm was shown to be more well applied to the experimental results compared with the classical Langmuir adsorption isotherm. Based on this, regarding the adsorption system which following the Langmuir model more precise design and controllable operation of the process were considered to be attainable when the adsorption process is analyzed employing the altered adsorption isotherm.

• The Research Journal of the Costume Culture
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• v.19 no.5
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• pp.1019-1030
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• 2011

The aim of this study was to develop a pattern of flight attendant uniform shirts to provide better comfort for their work postures. Flight attendants' work postures were evaluated to determine the problems of clothing and mobility during their work. The pattern of the flight attendants' uniform shirt was altered by applying dynamic wearing ease(DWE). DWE was calculated from four standardized dynamic postures and a static posture. An experimental garment was made with the altered postures. The researcher redesigned the pattern of the uniform shirts, which minimizes physical limitations in movements. The fit and mobility of the shirts were evaluated. Results of this study are as follows. First, the five representative work postures were selected by "clothing stress" and "repetitiveness." These postures included raised arms, twisting midriff and shoulder postures. Five representative postures were selected by using the ergonomic posture assessment device index(OWAS). Second, the experimental garment was developed by applying DWE across the back and at armhole depth, back length, and side length. Third, the fit and mobility of the experimental garments and the original uniform shirts were compared at the flight working environment set and 5 dynamic body postures of raising arms. The experimental garments made with an altered pattern provided better fit and mobility than the original sample shirts.

• The Journal of Engineering Geology
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• v.26 no.1
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• pp.117-128
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• 2016

Chemical reaction tests were performed to assess the properties of hardened specimens of cement pastes (KS-1 Portland and Class G) exposed to supercritical CO₂ for 1, 10, and 100 days. After exposure, the samples' measured permeability and strength were compared with values measured for pristine samples. The pristine cements had permeabilities of 0.009~0.025 mD, which increased by one order of magnitude after 100 days of exposure (to 0.11~0.29 mD). The enhancement of permeability is attributed to the stress release experienced by the samples after removal from the pressure vessel after exposure. Despite its enhancement, the measured permeability mostly remained lower than the API (American Petroleum Institute) recommended maximum value of 0.2 mD. The degradation of the cement samples due to exposure to supercritical CO₂ led to a layer of altered material advancing inwards from the sample edges. The Vickers hardness in the altered zone was much higher than that in the unaltered zone, possibly owing to the increase in density and the decrease in porosity due to the carbonation that occurred in the altered zone. Hardness close to the edge within the altered zone was found to have decreased significantly, which is attributed to the conversion of C-S-H into less-strong amorphous silica.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.3
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• pp.297-306
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• 2003

Works were focused on back pressure characteristics of ceramic fiber filter on DPF (Diesel Particulate Filter) system and experiments were performed to select appropriate filter which can filter particulates. Filters were installed on metal -support tube which has openings for exhaust gas flow. Ceramic fiber filters with high specific surface area and adequate high temperature strength are commercially available for filtration of diesel particulates and in -situ hot regeneration. Thus, ceramic blanket and ceramic board which are used as insulating media were applied to filter and filtration apparatus was installed on exhaust gas line connected to 2.0 L diesel engine. Alternating filter structure to adapt DPF system, collection efficiency test of diesel particulates was measured. In case of ceramic blanket, pressure drop was low, caused by the destruction of soft structures. Also, particulate collection efficiency was decreased depending on loading time. In case of ceramic board, structure design was altered to reduce back pressure on DPF system. Structure design was altered to induce Z-flow by making 10 mm and 5 mm holes on the surface of media. Alteration of 5 mm hole showed that media have low back pressure but particulate collection efficiency was 77%, while 10 mm hole showed that of 90%.

• Journal of Ginseng Research
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• v.12 no.1
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• pp.53-62
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• 1988

A field experiment was conducted in the arid interior of British Columbia, Canada to assess the seasonal soil temperature and moisture regimes in an American ginseng garden. As a consequence of the man-modified microclimate (elevated shade canopy and surface covering of mulch), the growing environment of the crop was fundamentally altered when compared to adjacent agricultural growing environments. In the ginseng garden, soil temperatures were found to remain low throughout the growing season whereas soil moisture remained high when compared with the outside garden environment. These results indicate that even in the hot, arid environment of the interior of British Columbia, the growing of ginseng is undertaken in sub-optimal conditions for the major part of the growing season. This poses challenges for the producers of the crop to modify the architecture of the gardens to enhance the soil regime without creating a deleterious aerial environment.

• Journal of the Korean Geographical Society
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• v.33 no.2
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• pp.143-163
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• 1998

In order to clarify the depositional environment and sea-level change at Ilsan area including Gawaji and Saemal valley plains, which is located at the right side in downstream of the Han River, boring data, radiocabon dating and diatom analysis were comprehensively investigated. As a result, the palaeogeographies fo this area altered by the transgressions and regressions after 7,000 y. BP could be restored. The high tide sea-level(mean high water level of spring tide) was arrived ca. 7,000y. BP at the valley plain and risen to ca. 5.5m at ca. 5000y. BP. Since then, the sea-level was kept up the same level to ca. 3,200 BP. The descended sea-level to ca. 2,300 BP was risen up to ca. 5.8m in ca. 1,800 y. BP. It is presumed that such a sea-level change as well as the different sediments in quantity supplied from the river basin of the valley plain could be effected to change diversely the depositional environment of the study area and eventually to the prehistoric human life.

• Toxicological Research
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• v.31 no.4
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• pp.347-354
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• 2015

Excess manganese (Mn) is neurotoxic. Increased manganese stores in the brain are associated with a number of behavioral problems, including motor dysfunction, memory loss and psychiatric disorders. We previously showed that the transport and neurotoxicity of manganese after intranasal instillation of the metal are altered in Hfe-deficient mice, a mouse model of the iron overload disorder hereditary hemochromatosis (HH). However, it is not fully understood whether loss of Hfe function modifies Mn neurotoxicity after ingestion. To investigate the role of Hfe in oral Mn toxicity, we exposed Hfe-knockout ($Hfe^{-/-}$) and their control wild-type ($Hfe^{+/+}$) mice to $MnCl_2$ in drinking water (5 mg/mL) for 5 weeks. Motor coordination and spatial memory capacity were determined by the rotarod test and the Barnes maze test, respectively. Brain and liver metal levels were analyzed by inductively coupled plasma mass spectrometry. Compared with the water-drinking group, mice drinking Mn significantly increased Mn concentrations in the liver and brain of both genotypes. Mn exposure decreased iron levels in the liver, but not in the brain. Neither Mn nor Hfe deficiency altered tissue concentrations of copper or zinc. The rotarod test showed that Mn exposure decreased motor skills in $Hfe^{+/+}$ mice, but not in $Hfe^{-/-}$ mice (p = 0.023). In the Barns maze test, latency to find the target hole was not altered in Mn-exposed $Hfe^{+/+}$ compared with water-drinking $Hfe^{+/+}$ mice. However, Mn-exposed $Hfe^{-/-}$ mice spent more time to find the target hole than Mn-drinking $Hfe^{+/+}$ mice (p = 0.028). These data indicate that loss of Hfe function impairs spatial memory upon Mn exposure in drinking water. Our results suggest that individuals with hemochromatosis could be more vulnerable to memory deficits induced by Mn ingestion from our environment. The pathophysiological role of HFE in manganese neurotoxicity should be carefully examined in patients with HFE-associated hemochromatosis and other iron overload disorders.