• Journal of the Korea Institute of Building Construction
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• v.11 no.2
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• pp.189-199
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• 2011

Installation of a proper root barrier in a green roof system is very important in order to protect the concrete slab of roof and the root penetration in the waterproofing layer. To select the proper root barrier materials and methods, it is necessary to understand the environmental conditions affecting the waterproofing-root barrier system in green roof construction site. Therefore, we suggested as the environmental performance indexes four kinds of performance requirements; root penetration, chemical attack by chemical agent or fertilizer, load impact by soil depth and size of plant, and water pressure. The related four test methods were suggested for the inspection of these performance indexes. In this research, we could suggest for kinds of test methods as standard test methods to evaluate the environmental performance of waterproofing-root barrier for greening roof system.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.4
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• pp.37-44
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• 2019

The purpose of this study is to rationally determine the priority of seismic reinforcement of main(key) members of bridges. Cable Supported bridge was selected as the evaluation target and the reliability based on the probability distribution was used to evaluate the seismic fragility of the key members as a quantitative indicator. The safety factor, which is a random variable, is considered an artificial (fixed load and live load) load and a natural (earthquake, wind, temperature, etc.) load. The seismic load is applied as a possible earthquake during the lifetime of the bridge. From analyzing the fragility of each key member based on the seismic reliability, it can be concluded that the shoe (23.8%) was the most fragile, where the other members are ranked as place concrete (20.5%), pier (18.9%), foundation (17.3%) and cable (5.0%) respectively.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.1
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• pp.1-8
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• 2015

Wind power systems have gained much attention due to the relatively high reliability, good infrastructures and cost competitiveness to the fossil fuels. Advances have been made to increase the power efficiency of wind turbines while less attention has been focused on structural integrity assessment of structural sub-systems such as towers and foundations. Among many parameters for integrity assessment, the most perceptive parameter may be the induced horizontal displacement at the hub height although it is very difficult to measure particularly in large-scale and high-rise wind turbine structures. This study proposes an indirect displacement estimation scheme based on the combined use of inclinometers and accelerometers for more convenient and cost-effective measurements. To this end, (1) the formulation for data fusion of inclination and acceleration responses was presented and (2) the proposed method was numerically validated on an NREL 5 MW wind turbine model. The numerical analysis was carried out to investigate the performance of the propose method according to the number of sensors, the resolution and the available sampling rate of the inclinometers to be used.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.2D
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• pp.191-197
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• 2009

This study choose the Criteria by conducting survey questionnaire of expertise, ANP analysis, and reviewing literature to samples of School Zone in a synthetic and reasonable way. It draws the estimating factors including a variety of existing aspects (user, facility, operation and management, and education and institution) from the analyses and applies ANP to reflect the decision making process. The results show as follows: first, first level of weights presents proportion of 'facility' and 'user' takes 65% of total weights. It implies that the facility protects children from obstacles is the top priority of the settings. second, the second level of weights present similar importance with the first level. Facility management, road to school, surroundings, safety facility, decelerating facility hold approximately 72% of overall levels. This indicates that improving and repairing surroundings, and safety and decelerating facility are the first priority to consider. These estimating indicators will be properly utilized to rationally appoint prevention zone with reflecting various factors and social class.

• Journal of the Korean Geotechnical Society
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• v.40 no.2
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• pp.105-113
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• 2024

Underground buried cables can cause disconnections during the construction of roads and other subterranean structures due to uncertain designs. This paper describes experiments conducted to detect and verify the locations of these cables utilizing ground penetrating radar (GPR). The experiments were carried out at an active road construction site, where cable burial was anticipated. The GPR used operated within a frequency range of 400 MHz to 900 MHz to probe underground structures. The exploration methodology consisted of an initial GPR test to survey the entire area, followed by a secondary test informed by the results of the initial experiment, incorporating a diverse and increased number of lines. The findings confirmed the hyperbolic reflection patterns of cables at consistent locations along the same lines. These patterns were then compared to existing designs to corroborate the presence of cables at the identified locations. This research establishes an effective GPR methodology based on the electromagnetic wave reflection pattern, specifically the hyperbola, to detect difficult-to-locate underground buried cables.

• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.519-526
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• 2003

Pancreatic lipase and ${\alpha}$-amylase inhibitory activities in purified extracts of pumpkin and job's tear were studied. Pancreatic lipase inhibitory activity was determined by measuring the rate of releasing oleic acid from triolein, and ${\alpha}$-amylase inhibitory activity was determined by iodometric method. The extracts of pumpkin and job's tear were purified using silica gel and C-18 gel column chromatographies. Treatment of pumpkin extract $(120\;{\mu}g/mL)$ in 3T3-L1 preadipocyte decreased differentiation about 95% and blocked accumulation of lipid. Body weights of rats fed high-fat diet containing dietary supplement decreased about 13% as compared with those fed only highfat diet. These results revealed dietary supplement is a good obesity-reducing material for decreasing lipid and carbohydrate absorptions.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.5
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• pp.584-593
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• 2021

The sediment makes up the sea floor and plays an important role as a habitats for living things in the sea. However, pollution of coastal sediment due to internal and external factors such as inflow of contaminants from land and self-pollution becoming more serious, the needs for management of sediment that play an important role in ecology, is increasing. In particular, the review and evaluation of the effects of sediment in marine development projects including reclamation and dredging, have significance in terms of proactive protection and management of surrounding ecosystems. This study proposed the improvement measures for marine sediment management standards on the sea area utilization consultation for the development of public water. For the purpose, The evaluation and management standards of domestic and overseas marine sediments were reviewed and compared. The sediment environment guidelines under the Marine Environment Management Act of Korea were reviewed. Accordingly, the cases of Canada and NOAA, which have various evaluation standards consist of comprehensive factors, were analyzed. For analysis of operational cases, the port and fishing port development projects for the last five years (2016-2020) that are considered to have the greatest impact on sediments among the sea area use consultations were also reviewed. Finally, this study suggested that the assessment factors for ecological hazards and potential human risks should be considered in the sediment environmental standards in the sea area utilization consultation system.

• Journal of the Korean Geotechnical Society
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• v.39 no.7
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• pp.49-56
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• 2023

Gravel is commonly employed to enhance the bearing capacity of foundations and provide stable support for structures. However, effectively assessing the ground characteristics in the presence of gravel poses significant challenges. This study aims to compare the resolution of ground containing gravel using electrical resistivity, elastic wave surveys, and ground penetration radar (GPR). Nondestructive methods are applied at construction sites where soil improvement is carried out using gravel. The experiments focus on shallow depths, and the obtained results cover depths up to 2 m. Both the electrical resistivity and elastic wave techniques exhibit similar behavior in their findings, indicating comparable outcomes. However, GPR has limitations in observing the characteristics of ground with gravel. Dynamic cone-penetration tests were conducted to validate these findings. The electrical resistivity and elastic wave profiles exhibited similar behaviors in localized areas, further supporting their compatibility and reliability.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.744-754
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• 2017

In this study, an analytic hierarchy process (AHP) was conducted with the aim of developing a post-disaster refugee housing performance index system (PPS) to improve the post-disaster refugee housing (PRH) performance criteria for the foundation of quality-based development. The PRH was defined as a mid-term temporary housing facility that is used for a certain period before the permanent housing is established. The safety, rapidity, reusability, habitability, and economy were derived from major performance factors through prior research. A hierarchical PPS was organized by linking the major performance factors with the whole life cycle process of PRH. The priority of each performance index of PPS was determined quantitatively using the analytic hierarchy process through an expert survey. Based on AHP analysis, the performance criterion of the total weight 1-10 ranking and the performance criterion of the first rank in each category were classified into the essential performance criterion (must be achieved) and the others were classified into the recommended performance criterion (optional achieved) and the performance index was constructed considering all stages of PRH development. With the completion of the PRH performance index, it is expected that victims will be able to secure stable residence and return to their daily lives quickly.

• Journal of Food Hygiene and Safety
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• v.28 no.2
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• pp.146-151
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• 2013

Perilla frutescens usually dieted in East Asian country such as Korea and Japan. Antioxidant, antiinflammatory and anticancer activities of perilla leaves have been founded. In previous study, we confirmed that caffeic acid, major compound of perilla, was accumulation by sucrose aqueous solution and thus antioxidant effect of perilla was enhanced. In this study, we investigated the protective effect of functional perilla leaves extract (PLE) against tert-butyl hydroperoxide(t-BHP) induced-oxidative hepatotoxicity. The pretreatment with PLE (250, 500 and 1000 mg/kg b.w.) for 5 days before a single dose of t-BHP (i.p.; 0.5 mmol/kg) significantly lowered the serum levels of aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase dose-dependently. And we confirmed that the indicators of oxidative stress were remarkably reduced in the liver, such as the glutathione contents and malondialdehyde, marker of lipid peroxidation. Pathological histology of the rat livers tissues showed that PLE reduced the hepatocyte degeneration and neutrophilic infiltration of liver induced by t-BHP. These results suggest that functional perilla frutescens has the protective effect of liver against t-BHP-induced oxidative hepatic stress in rats.