• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.1C
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• pp.45-51
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• 2010

In urban area, design and construction of civil engineering structures such as subway tunnel, underground space and deep excavation is impeded by unreliable site investigation. Variety of embedded objects, electric noises and traffic vibrations degrades the quality of site investigation, whatever the site-investigation technique would be. In this research, a preliminary research was performed to develop a dedicated site investigation technique for urban geotechnical sites, which can overcome the limitations of urban sites. HiRAS (Hybrid Integration of Surface Waves and Resistivity) technique which is the first outcome of the preliminary research was proposed in this paper. The technique combines surface wave as well as electrical resistivity. CapSASW method for surface-wave technique and PDC-R technique for electrical resistivity survey were incorporated to develop HiRAS technique. CapSASW method is a good method for evaluating material stiffness and PDC-R technique is a reliable method for determination of underground stratification even in a site with electrical noise. For the inversion analysis of HiRAS techniuqe, a site-specific relationship between stress-wave velocity and resistivity was employed. As for outgrowth of this research, the 2-D distribution of Poisson's ratio could be also determined.

• Journal of the Korean Wood Science and Technology
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• v.44 no.5
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• pp.617-621
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• 2016

On-site survey on glue-laminated board (GLB) manufacturers of Malaysia, Indonesia, and China was conducted to identify the cause of interception of regulated pest from imported GLBs from those countries, and to suggest optimal manufacturing processes of GLB for preventing quarantine risk associated with imported GLBs. The cause of pest interception was improper manufacturing processes, such as air drying or inadequate kiln drying of green laminae, improper storage of dried laminae before finger jointing and edge gluing, and/or incomplete packing of GLBs. In particular, Paulownia GLB manufacturing processes used in China, including air drying of laminae, were mostly poor in terms of preventing quarantine risk associated with imported GLBs. From now on, for preventing quarantine risk associated with imported GLBs, importers have to ask foreign manufacturers spontaneously to use proper manufacturing processes (adequate kiln drying of green laminae, proper storage of dried laminae, and complete packaging of final GLBs).

• Journal of the Korean GEO-environmental Society
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• v.12 no.7
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• pp.5-12
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• 2011

When choosing the support pattern of tunnel, the characteristics of rock are identified from the result of the surface geologic survey, boring, and geophysical prospecting and laboratory test. And a rock mass rating is classified and excavation method and standard support pattern are designed considering rock classification, domestic and international construction practices, numerical analysis. According to the revised design standard for tunnel, it was recommended to classify the rock mass rating for the design of tunnel into a rating based on RMR. If necessary, it proposed a flexible standard allowed applying more atomized the rock mass rating and Q-System. Also, the resonable verification of the support pattern must be accompanied because the factors affecting the structure and behavior of ground during the construction of tunnel are the main factors of uncertainty factors such as the nature of ground, ground water and the characteristics of structural materials. These days, such verification method is getting more specialized and diversified. In this study, the empirical method, numerical analysis and comparative analysis of in situ measurements were used to prove the reasonableness in the support pattern by RMR and Q-value on the Imha Dam emergency spillway.

• The Journal of Engineering Geology
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• v.5 no.1
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• pp.1-20
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• 1995

A train overturn accident occurred on March 1993 in the Gupo area, northern part of Pusan, unfortunately had taken a heavy toll of lives and caused a great loss of property as well. The reasons for the subsidence of the basement under the railroads, which presumed to be the main cause of the accident, have been investigated from many different angles, including conventional geotechnical investigation methods. The deduced nuin reasons of the subsidence were: 1. blasting for tunnel excavation (NATM) at about 39 meter under the railroads, and 2. unexpected change of bedrock conditions along the direction of tunnel. But this accident was derived nrranlv from the lack of geological and geotechnical information under railroad area because it was impossible to drill beneath the railroads. This paper introduces a new geophysical survey techniqueseisrnic geotomography, and shows some results of the method applying to investigate the underground structure of the accident area. This method not only overcomes the unfavourable environment which many conventional investigation methods cannot face, but produces an image of underground structure with high resolution. Furthermore, the outputs from geotomogaphic analysis could provide very valuable in-situ basic parameters (like seismic velocities, elastic moduli, etc.) which is essential to the design and construction.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.1
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• pp.18-29
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• 2019

ROV surveys were conducted using 500 meter mini class ROV with HD video camera, 2 LED lights, a simple manipulator and 8 thrusters near the Dokdo and Simheungtaek seamount. Total six dives have been conducted using the ROV "V8 SII" from Sweden and ROV's support ship, "KOSAL V" at 4 stations between 45 and 370 meters with diving time ranged from 30 to 120 minutes. Dense communities of sea anemone (Actinostolidae sp.) and ophiuroids (Ophiuridae sp.) on the surface of rocky bottom and snow crab on the soft bottom with muddy-sand were observed at northwestern part of Simheungtaek seamount. We obtained the following results 1) habitats information for snow crab, one of the major fisheries resources, and deep-sea fauna, 2) observation on the specific topography and sediment conditions, 3) observation of the seabed surface covered with the discarded fishing gears. This study represents the first report of in situ visual observation of deep-sea organisms and their habitats near the Dokdo slopes and flat top of the Simheungtaek seamount in the East Sea. These results indicated that immediate oceanographic survey using the mini class ROV is available in the East Sea.

• Journal of Korea Water Resources Association
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• v.51 no.12
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• pp.1181-1194
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• 2018

This study suggests a novel approach of estimating stream flow discharge using the Synthetic Aperture Radar (SAR) images taken from 2015 to 2017 by European Space Agency Sentinel-1 satellite. Fifteen small to medium sized rivers in the Han River basin were selected as study area, and the SAR satellite images and flow data from water level and flow observation system operated by the Korea Institute of Hydrological Survey were used for model construction. First, we apply the histogram matching technique to 12 SAR images that have undergone various preprocessing processes for error correction to make the brightness distribution of the images the same. Then, the flow estimation model was constructed by deriving the relationship between the area of the stream water body extracted using the threshold classification method and the in-situ flow data. As a result, we could construct a power function type flow estimation model at the fourteen study areas except for one station. The minimum, the mean, and the maximum coefficient of determination ($R^2$) of the models of at fourteen study areas were 0.30, 0.80, and 0.99, respectively.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.39 no.1
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• pp.37-42
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• 2021

Munseom (Island) is known as the largest native Elaeocarpus sylvestris var. ellipticus in Korea. Recently, disease damage from the E. sylvestris var. ellipticus community has been reported in Munseom. This study was conducted to understand the damage situation and growth characteristics of the E. sylvestris var. ellipticus population in Munseom. The purpose of this study was to evaluate the spontaneous regeneration potential of the community by grasping the characteristics of the population of surviving E. sylvestris var. ellipticus individuals, and to discuss ways to restore native habitats. A total population survey was conducted to determine the distribution status of E. sylvestris var. ellipticus individuals. The field survey carefully recorded the height of tree, DBH, DRH, and growing status, along with GPS location information of the individual. The growth status of E. sylvestris var. ellipticus individuals distributed in Munseom and the characteristics of tree height, DBH, DRH of each individual were analyzed. The total number of E. sylvestris var. ellipticus populations identified in Munseom was 293. The dense E. sylvestris var. ellipticus community reported in 2005 has been identified as being greatly damaged or damaged. In particular, the damage was more serious in mature trees with a height of 6m or more forming the canopy layer in the forest, and it was confirmed that 80.6% of the mature trees died. In the growth characteristics of the old-growth tree, which is an indicator of the health of the forest based on DRH, 75.4% died or the growth condition was found to be poor. In order to restore the native habitat of E. sylvestris var. ellipticus in Munseom, conservation efforts such as pest control, preservation of mature trees, control of the territory of young trees, and reintroduction after ex-situ transplantation etc. are considered necessary.

• Journal of Environmental Impact Assessment
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• v.31 no.1
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• pp.11-46
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• 2022

This study was carried out to examine vascular plants and invasive alien plants in Gyodong Island, located at the northwestern Civilian Control Line (CCL) of Ganghwa-gun, Incheon, and to use them as basic data for systematic management of identified plants and establishing biodiversity conservation measures. The survey was conducted 13 times from April 2019 to August 2021. The vascularflora in Gyodong Island was identified as 109 families, 378 genera, 641 species, 15 subspecies, 49 variants, 8 forma, a total of 713 taxa. This was found to be about 15.36% of the total 4,641 taxa of vascular plants in Korea. The northern linage plants on the Korean Peninsula appearing in the Gyodong Island area were identified in 83 classification groups, including Red-based leaf edge (Carex erythrobasis H.Lev. & Vaniot). Korea endemic plants were identified as 16 taxa such as Seoul wild-ginger [Asarum heterotropoides var. seoulense (Nakai) Kitag.], and a total of 20 taxa of rare plants designated by IUCN were observed, including the endangered grade Beardless iris (Iris ruthenica Ker Gawl.). Floristic target species were classified with a total of 99 taxa. For V grade, Beardless iris 1 taxon was found. and also IV grade and III grade were identified in 8 taxa and 20 taxa respectively. The invasive alien plants identified as 75 taxa, such as Verbesina alternifolia (L.) Britton ex Kearney. The naturalization rate was 10.51%, and the urbanization index was calculated as 23.29%. Since large-scale construction has been currently underway on Hwagae Mt. in Gyodong Island as the target of survey area, the influx of invasive plants will be expected to promote. Therefore, it is urgent to establish in-situ protection and conservation measures for notable plants such as Beardless iris and Water smartweed [Persicaria amphibia (L.) S.F.Gray].

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.35 no.4
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• pp.14-28
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• 2017

Currently, the object of conservation in heritage conservation is defined as "the value of the heritage" and the value-based management plan has been introduced. Most of traditional temples in korea have been sustained over 1000 years, which make them mixed heritages, including cultural, religious and natural heritages. Therefore, traditional temples should be managed by value-based management plans. This article aims to develop the values and assessment indicators of traditional temple areas and to evaluate the importances of the values and indicators, in order to prepare the basic materials for conserving the values of traditional temples. This study used the diverse research methods such as literature review, in-situ survey, in-depth interview, focus group interview, questionnaire survey. The results showed that the identified values and assessment indicators of traditional temple area were defined as three classes: high class value was consisted of intrinsic value and use value, middle class values were 10 (5 for intrinsic and 5 for use value). 5 middle class values belonging to the intrinsic value were religious/humanity, historical, cultural, environmental/ecological, landscape values. 5 values constituting the use value were social, educational, therapeutic, recreational, and economic values. As a low class, 102 assessment indicators were identified. 60 participants (30 buddhism people, 30 KNPS people) evaluated the importances of the developed values and indicators, using the pairewise comparison for the values and the interval scale for the indicators. It was found that both groups evaluated the use value more important than the intrinsic value and that religious/humanity, landscape, environmental/ecological, economic, recreational values were evaluated more important than the other middle class values. It was also revealed that the two groups were different in their assessments of the indicators. Based on the results, some suggestions were made to improve the management of the traditional temple areas.

• Korean Journal of Environment and Ecology
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• v.37 no.4
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• pp.302-314
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• 2023

This study aims to explore the direction for Korea's effective response to Target 3 (30by30), which can be said to be the core of the Kunming-Montreal Global Biodiversity Framework (K-M GBF) of the Convention on Biological Diversity (CBD), to find the direction of systematic OECM (Other Effective area-based Conservation Measures) discovery at the national level through a survey of global conceptual review and expert perception of OECM. This study examined ① the use of Korean terms related to OECM, ② derivation of determining criteria reflecting global standards, ③ deriving types of potential OECM candidates in Korea, and ④ considerations for OECM identification and reporting to explore the direction for identifying systematic, national-level OECM that complies with global standards and reflects the Korean context. First, there was consensus for using Korean terminology that reflects the concept of OECM rather than simple translations, and it was determined that "nature coexistence area" was the most preferred term (12 people) and had the same context as CBD 2050 Vision of "a world of living in harmony with nature." This study suggests utilizing four criteria (1. No protected areas, 2. Geographic boundaries, 3. Governance/management, and 4. Biodiversity value) that reflect OECM's core characteristics in the first-stage selection process, carrying out the consensus-building process (stage 2) with the relevant agencies, and adding two criteria (3-1 Effectiveness and sustainability of governance and management and 4-1 Long-term conservation) and performing the in-depth diagnosis in stage 3 (full assessment for reporting). The 28 types examined in this study were generally compatible with OECMs (4.45-6.21/7 points, mean 5.24). In particular, the "Conservation Properties (6.21 points)" and "Conservation Agreements (6.07 points)", which are controlled by National Nature Trust, are shown to be the most in line with the OECM concept. They were followed by "Buffer zone of World Natural Heritage (5.77 points)", "Temple Forest (5.73 points)", "Green-belt (Restricted development zones, 5.63 points)", "DMZ (5.60 points)", and "Buffer zone of biosphere reserve (5.50 point)" to have high potential. In the case of "Uninhabited Islands under Absolute Conservation", the response that they conformed to the protected areas (5.83/7 points) was higher than the OECM compatibility (5.52/7 points), it is determined that in the future, it would be preferable to promote the listing of absolute unprotected islands in the Korea Database on Protected Areas (KDPA) along with their surrounding waters (1 km). Based on the results of a global OECM standard review and expert perception survey, 10 items were suggested as considerations when identifying OECM in the Korean context. In the future, continuous research is needed to identify the potential OECMs through site-level assessment regarding these considerations and establish an effective in-situ conservation system at the national level by linking existing protected area systems and identified OECMs.