• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.23-26
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• 2002

Ternary blended concrete containing both fly ash and granulated blast furnace slag is initial cost effective, and environment friendly. Furthermore, it has many technical advantages such as improvement of long term compressive strength, rheology property, reduction of hydration heat, etc. However, use and data on the performance of ternary blended concrete are limited, and it is necessary to study on the adoption of this technology. This study examined the durability performance of ternary blended concrete comparing with binary blended concrete and ordinary portland concrete. From the results of this study, it was concluded that ternary blended concrete is very suitable to submerged zone under maine environment.

• Safety and Health at Work
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• v.8 no.3
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• pp.282-289
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• 2017

Background: The objective of this study was to report on the prevalence of musculoskeletal pain in lobstermen in the northeast USA. Methods: Crews were randomly selected from those licensed to fish in Maine and Massachusetts and followed prospectively. The survey used a Nordic Musculoskeletal Questionnaire format to characterize musculoskeletal disorders. Results: A total of 395 individuals participated. One half of the respondents reported low back pain. Back pain was attributed to or exacerbated by lobstering. Low back pain was prevalent among both captains and sternmen, while sternmen reported more hand/wrist pain than captains. Multiple locations for pain were common in individual participants. Conclusion: Equipment or technology to assist material handling should be a priority, as the body segments with high prevalence of pain (back, hand/wrists, shoulders, knees) are all affected by the repetitive and forceful handling of the lobster traps.

• Ocean Science Journal
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• v.41 no.3
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• pp.181-189
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• 2006

Frontal areas between warm and saline waters of the Kuroshio currents and colder and diluted waters of the East China Sea (ECS) influenced by the Changjiang River were identified from the satellite thermal imagery and hydrological data obtained from the Coastal Ocean Process Experiment (COPEX) cruise during the period between March $1^{st}$ and $10^{th}$, 1997. High chlorophyll concentrations appeared in the fronts of the East China Seas with the highest chlorophyll-a concentration in the southwestern area of Jeju Island (${\sim}2.9\;mg/m^3$) and the eastern area of the Changjiang River Mouth (${\sim}2.8\;mg/m^3$). Vertical structures of temperature, salinity and density were similar, showing the fronts between ECS and Kuroshio waters. The water column was well mixed in the shelf waters and was stratified around the fronts. It is inferred that the optimal condition for light utilization and nutrients induced both from the coastal and deep waters enhances the high phytoplankton productivity in the fronts of the ECS. In addition, the high chlorophyll-a in the fronts seems to have been associated with the water column stability as well.

• Journal of Environmental Impact Assessment
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• v.22 no.3
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• pp.265-276
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• 2013

This study assessed documentation status of each environmental assessment items by analyzing the 243 case of marine EIS on the Consultation System of Sea Area Utilization. Observed rate of tidal elevation, current, temperature, salinity in maine environment were below 20%. The EFDC tool is applied substantially in hydrodynamic modeling. The verification process, however, is very insufficient using the recent observed data. Also, in-situ assessment rate of pelagic organism such as phytoplankton was below 50%, and assessment for Chlorophyll a was not accomplished. Ecological index evaluation for zooplankton and benthic ecosystem were not considered in statements. Especially, the rational assessment on the fisheries resources and protected species were very limited. It was necessary that the core assessment items (checklists) were established for environmental scoping. Furthermore, suggestion of information related to development, regional coastal management plan, aquaculture farms, and facilities were enhanced. The redundancy problem of proceedings between Environmental Impact Assessment and Sea Area Utilization Assessment System was improved.

• Korean Journal of Organic Agriculture
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• v.23 no.2
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• pp.323-334
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• 2015

This study was conducted to develop environment-friendly agricultural products with anti-microbial activity against Acidovorax avenae subsp. citrulli as a pathogen of bacterial fruit blotch in cucurbit. Schlechtendalia chinensis was extracted by MeOH and solvent fraction. The hexane fraction, which showed highest value of anti-microbial activity, was analyzed by GC-MS. Each mass spectra, corresponding to each peak of chromatogram, was compared to MS database of Wiley library. As a result, myristic acid, palmitic acid and 3-n-pentadecylphenol were identified as maine compounds showing antimicrobial activity against A. avenae subsp. citrulli. Bioassay using commercial myristic acid, palmitic acid and 3-n-pentadecylphenol to test for the anti-microbial activity conformed the anti-microbial activity of potential active compounds, and myristic acid and 3-n-pentadecylphenol showed strong activity. In conclusion, myristic acid and 3-n-pentadecylphenol identified from S. chinensis were anti-microbial chemicals.

• Ocean and Polar Research
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• v.29 no.3
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• pp.273-282
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• 2007

For an efficient management and utilization of marine biodiversity information, we made an attempt to develop the Korea Marine Biodiversity Information System (KoMBIS), building a species name inventory of Korea marine organisms. The inventory includes 17 organism groups: phytoplankton, zooplankton, algae and halophyte, sponges, cnidarians, rotifers, nematodes, bryozoans, brachiopods, molluscs, echiurans, annelids, arthropods, echinoderms, urochordates and fish. The species names were collected from 37 different references and reviewed for validity by taxonomists, which resulted in 9,798 valid names in addition to 1,845 synonyms. The Korea marine species inventory is the first one of this kind, for previous Korean species name inventories were mostly composed of terrestrial and freshwater organisms. KoMBIS, the information system developed, contains not only the species name but also information on morphological and ecological characteristics such as distribution, DNA barcode, and references. This system is convenient for the inputting of new data and servicing users through the internet, so that management and utilization of the biodiversity information is more efficient. Linking the DNA barcode data with species information provides an objective measure for identification of a species, which accommodates the recommendation of Consortium for the Barcode of Life, and makes the Korea marine biodiversity information compatible with international databases. Considering the frequent exchange of marine organisms internationally via ballast water and such issues as climate change, this information system will be useful in many areas of marine biodiversity.

• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.951-962
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• 2015

To develop environment-friendly agricultural products with anti-microbial activity against Sclerotinia sclerotiorum as a pathogen of sclerotium disease, Aristolochia tagala Champ. was extracted by methanol and its extract was fractionated into several solvent fractions. The chloroform fraction, which showed the highest antimicrobial activity, was separated by column chromatography and obtained forty three subfractions. The forty three fractions were searched the anti-fungal activities by bioassay. The most active No. 26 subfraction was analyzed by GC-MS. Each mass spectra, corresponding to each peak of chromatogram, was compared to MS database of Wiley library. As a result, 2,4-di-tetra-butyl-phenol, 2-mono-palmitin, 1-mono-stearin were profiled as maine compounds in No. 26 subfraction. Bioassay using commercial 1-mono-stearin to test for the anti-microbial activity conformed the antimicrobial active compound. In conclusion, 1-mono-stearin identified from Aristolochia tagala Champ. was antimicrobial chemical against Sclerotinia sclerotiorum.

• The KIPS Transactions:PartD
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• v.16D no.2
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• pp.177-184
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• 2009

Environmental monitoring systems are widely developed for analyzing environment and understanding an ecosystem according to the advance of wireless communication and various sensing techniques. To extract useful information, it requires high cost for processing a query, because these systems have to handle huge volume of raw sensor data which is transmitted from a wide area in environmental monitoring applications. Besides, it is also hard to answer an user defined query which requests to check current and near future condition. In this paper, we propose the monitoring system structure for processing a user defined query for environmental monitoring. It also describes the utilization of sensor data filtering and abstraction model. The designed abstraction model which is based on the slope grid in GIS supports fast data access and update. To analyze condition, the extracted data from abstraction model of each sensor type is combined in a query processor. It is useful to provide meaningful information to users.

• The KIPS Transactions:PartB
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• v.8B no.5
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• pp.429-440
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• 2001

To achieve a computer tutor framework with high learning effects as well as practicality, the goal of this research has been set to developing an intelligent tutor for problem-solving in mathematics domain. The maine feature of the CyberTutor, a computer tutor developed in this research, is the facilitation of a learning environment interacting in accordance with the learners differing inferential capabilities and needs. The pedagogical information, the driving force of such an interactive learning, comprises of tutoring strategies used commonly in various domains such as phvsics and mathematics, in which the main contents of learning is the comprehension and the application of principles. These tutoring strategies are those of testing learners hypotheses test, providing hints, and generating explanations. We illustrate the feasibility and the behavior of our propose framework with a sample problem-solving learning in geometry. The proposed tutorial framework is an advancement from previous works in several aspects. Firstly, it is more practical since it supports handing of a wide range of problem types, including not only proof types but also finding-unkown tpes. Secondly, it is aimed at facilitating a personal tutor environment by adapting to learners of varying capabilities. Finally, learning effects are maximized by its tutorial dialogues which are derived from real-time problem-solving inference instead of from built-in procedures.

• Journal of Environmental Impact Assessment
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• v.31 no.3
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• pp.141-160
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• 2022

The harbor construction projects can lead to various marine environmental problems including habitat degradation and loss, marine water pollution, change of flow patterns, erosion, scour, sedimentation, and so on. The EIA is a measure to prevent various environmental problems in advance from examining and minimizing the environmental impacts before the proposed developments are implemented. In addition, institutions reviewing EIA reports have made efforts to conduct scientific and standardized EIA by applying EIA guidelines for each project. This study aims to create a EIA guideline focusing on the harbor construction projects. Based on the review comments of the harbor construction EIA reports for the past 13 years (2009-2021) and the EIA guidelines of different types of projects, we identified the marine environmental problems and provided the appropriate guideline. This guideline summarizes and presents the contents which must be reviewed in the baseline condition survey, impact assessment, mitigation, and post-environmental impact investigation in the fields of marine fauna and flora, marine physics, and marine water and sediment quality. In the case of a baseline condition survey of marine fauna and flora, a method for selecting survey points considering the characteristics of sea area and project was presented. When estimating the impact of marine fauna and flora, we presented methods for predicting the impact on them due to the spread of suspended sediments and the damage to benthic habitats due to dredging and reclamation. In consideration of the characteristics of the sea area, we divided the survey items of the marine physics into essential items and supplementary items. In predicting the impact of marine physics, various methods for major issues such as seawater circulation, suspended sediment and bottom sediment transport, water temperature and salinity diffusion, seawater exchange, wave transformation, harbor tranquility, and shoreline change were presented. The research results will contribute to protect the marine environment by inducing more systematic and scientific surveys, impact assessments, and mitigation in the EIA process.