• KIEAE Journal
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• v.2 no.2
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• pp.39-44
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• 2002

Recently, underground spaces can be usually applied to the alternative of land use for parking. However, lack of window and natural light are among the most cited drawbacks associated with dark image of underground. If underground parking lots are designed to be positive and safe environment for people, openings for daylighting will play a significant role. The natural light and unobstructed view to outdoor are main elements to create optimal underground parking lots. This paper focuses on investigating the actual day lighting conditions and evaluating the day lighting performance of openings as potential lighting resources. For the study, the field measurements and Questionnaire surveys are conducted. And then, the day lighting performance of underground parking lots based on opening geometry and orientation are evaluated by scaled model experiments. As results, the feelings of safety and orientation of underground parking lots are improved by openings for day lighting regardless of the sizes. The required illuminances (daylight factor 0.5%) for underground parking lots can be satisfied in the skylight opening ratio of 4% or more.

• Korean Journal of Ecology and Environment
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• v.40 no.4
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• pp.511-519
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• 2007

It is known that phytoplankton biomass or turbidity are lower in waters with submerged macrophytes than those without submerged plants at a given nutrient level. We hypothesize that presence of submerged macrophytes would lower phytoplankton biomass below levels expected by total phosphorus levels through various mechanisms and that phytoplankton biomass would decrease more as the biomass increase of the submerged macrophytes. To find submerged macrophytes effectively lowering phytoplankton growth, we conducted spatial field surveys at 21 water bodies and a temporal monitoring at Seung-un 1 Reservoir, Anmyyeondo Island. We measured chlorophyll ${\alpha}$ concentrations and total phosphorus (TP) concentrations from waters in patches of submerged macrophytes with measurements of submerged plant biomass. Majority of our sites with submerged macrophytes showed much less chlorophyll a concentrations than the predicted ones from literature. Among submerged macrophytes studied, Myriophyllum spicatum and Hydrilla verticillata showed patterns of lowering chlorophyll ${\alpha}/TP$ ratios with increase of their biomass in both spatial and temporal surveys.

• Journal of the Korea Safety Management & Science
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• v.25 no.1
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• pp.39-50
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• 2023

This study analyzed the effect of workers' socio-psychological burden factors on musculoskeletal disorders. A survey was conducted targeting office and field workers in the Seoul metropolitan area. Analysis was performed using the results of 357 surveys out of 400 surveys. The analysis results were derived as follows. First, the socio-psychological burden factor did not show statistically significant results for musculoskeletal disorders. Second, it was found that job stress factors also had a positive effect on musculoskeletal disorders. Third, social psychological burden factors were found to be more positive than office workers than field workers. Fourth, there was a statistically significant correlation between job stress and musculoskeletal disease risk scores. From the above results, job stress factors affect musculoskeletal disease risk factors (work frequency, pain level, and duration) and the increase in musculoskeletal disorders and the number of accidents.

• Journal of Korean Society for Geospatial Information Science
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• v.20 no.3
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• pp.29-40
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• 2012

The method regarding obtaining various kinds of attribute data of spatial information, including that of digital map, is normally restricted to Geographic survey that deals with in-field surveys. Geographic surveying for drawing digital map, however, require much effort due to the fact that a surveyor has to characterize geographic features individually in the field. Not only does the Geographic survey cover large area, but also its need for manual drawing and surveying using Draft map makes it more expensive and time-consuming. Though some recent Geographic surveys take advantage of MMS(Mobile Mapping System) to collect computerized information, there are inevitable limits in creating digital map with such data. This research will analyze the problems in current Geographic surveys and suggest adequate methods and standards for Geographic surveys by researching the methods of domestic/international service organizations that deal with establishing spatial information. This study therefore will aim to enhance the efficiency of creating digital map and Geographic survey, which would ultimately maximize the applicability of pan-national digital map by improving reliability of digital map and upgrading the utilizability of Geographic survey data.

• 한국해양학회지
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• v.25 no.3
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• pp.131-134
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• 1990

Estimates of larval mortality for many marine fishes are based on field collections from several consecutive ichthyoplankton surveys, assuming that the surveys have covered the entire areas of larval habitats. The oceanic environment, however, is so dynamic and complicated that planktonic forms cannot stay within a confined area for a prolonged period. This note is prepared as a more detailed explanation of the estimates of fish larval mortality in the oceanic dispersing system, as a supplement of Kim and Bang (1990).

• Geophysics and Geophysical Exploration
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• v.7 no.1
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• pp.1-6
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• 2004

High-resolution S-wave reflection surveying has been successfully conducted on paved areas using a Land Streamer originally designed by the author. The main feature of the Land Streamer tool is the non-stretch woven belt on which geophone units are mounted to form a multichannel geophone array similar to a marine streamer. Because it is easily towed by a vehicle or by hand, the tool leads to high performance in field measurements and resultant cost-effectiveness of high-resolution reflection surveys. Although each geophone unit is coupled to the pavement through a metallic baseplate instead of being firmly planted in the ground, the Land Streamer tool provides comparatively clean data, unaffected by traffic noise even on the pavement. Thus, the tool is capable of expanding the opportunity for S-wave reflection surveys in urban areas where many surfaces are paved and traffic noise is severe. A series of high-resolution S-wave reflection surveys on paved areas delineated detailed structures of surface layers shallower than 60 m, and proved the wide applicability of the tool to engineering, environmental applications, and earthquake disaster prevention projects.

• Wind and Structures
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• v.14 no.6
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• pp.537-557
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• 2011

While there are a number of guidelines used throughout the world in the assessment of acceptability of tall building accelerations, none are based on systematically conducted surveys of occupant reaction to wind-induced motion. In this study, occupant response data were gathered by both a self-reporting mechanism and by interviewer-conducted surveys in control tower structures over a period of four years. These two approaches were designed in conjunction with experimental psychologists to ensure unbiased reporting. The data allowed analysis of perception thresholds and tolerability at different building frequencies and in different wind climates. The long-term nature of the studies also allowed an investigation of the causes and effects of adaptation to building motion. As the surveys were designed to allow multiple use during single storms, the effects of exposure duration were investigated. A final exit survey was conducted at the primary survey location to investigate views of the acceptability of wind-induced motion and the factors underlying these views. The findings of the field studies indicate that none of the currently used acceleration guidelines address all of the factors that contribute to occupant dissatisfaction. An alternative framework for assessing acceleration acceptability is proposed.

• Journal of Internet Computing and Services
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• v.21 no.6
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• pp.81-94
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• 2020

This study developed evaluation indicators for the comfort experience of virtual reality (VR) headsets by classifying, defining, and weighting cybersickness-causing factors using the Delphi research method and analytic hierarchical process (AHP) approach. Four surveys were conducted with 20 experts on VR motion sickness. The expert surveys involved the 1) classification and definition of cybersickness-causing dimensions, classification of sub-factors for each dimension, and selection of evaluation indicators, 2) self-reassessment of the results of each step, 3) validity revaluation, and 4) final weighting calculation. Based on the surveys, the evaluation indicators for the comfort experience of VR headsets were classified into eight sub-factors: field of view (FoV)-device FoV, latency-device latency, framerate-device framerate, V-sync-device V-sync, rig-camera angle view, rig-no-parallax point, resolution-device resolution, and resolution-pixels per inch (PPI). A total of six dimensions and eight sub-factors were identified; sub-factor-based evaluation indicators were also developed.

• Korean Journal of Plant Taxonomy
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• v.51 no.1
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• pp.33-48
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• 2021

We investigated the bryophyte flora of the Gayasan Mountain National Park in Korea by conducting 18 field surveys in from April of 2009 to November of 2016 at various sites on the mountains. During the surveys, we discovered 204 taxa comprising 57 families, 106 genera, 199 species, 2 subspecies, and 3 varieties. Among these, 145 species were reported as new to the flora of Gayasan Mountain. A checklist based on a study of 903 specimens is provided. The most notable species recorded during the surveys were the rare bryophytes Hattoria yakushimensis (Horik.) R. M. Schust., Nipponolejeunea pilifera (Steph.) S. Hatt., Drepanolejeunea angustifolia (Mitt.) Grolle, Lejeuena otiana S. Hatt., Cylindrocolea recurvifolia (Steph.) Inoue and Pogonatum contortum (Menzies ex Brid.) Lesq.

• Journal of the Korean association of regional geographers
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• v.16 no.5
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• pp.497-516
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• 2010

The purpose of this study is to critically investigate the places of the 'Daegusibyeong(大丘十詠)', written by Seo, Geojeong based on Chinese poem, old documents, and field surveys in terms of a geographical perspective. It is asserted that the controversial aspects on the 'Daegusibyeong(大丘十詠)' are corrected through the analysis of old documents and field surveys. The results are summarized in the followings. 1) Ascertain historical and geographical evidence on places of 'Daegusibyeong(大丘十詠)' are accomplished properly based on old documents and field surveys. 2) The existing misinterpretation of the 'Daegusibyeong(大丘十詠)' are corrected by the finding of one Chinese character in the 'Dongsasimseung(桐寺尋僧)', the seventh poem of 'Daegusibyeong(大丘十詠)' consisted of 10 Chinese poems. 3) Subjects and content of the 'Daegusibyeong(大丘十詠)' in Sagajib(四佳集) are more rightly written than those of the old documents such as Daegueubji(大丘邑誌), Sinjeungdonggukyeojiseungram(新增東國輿地勝覽). 4) A few mistakes in the subject and word of the 'Daegusibyeong (大丘十詠)' are corrected as compared with the those of the old documents. 5) It is assumed that the brand value and image of Daegu city will be improved if the 'Daegusibyeong(大丘十詠)' is restored based on the results of the study and its restoration is utilized in Daegu city tour program.