• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.25 no.2
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• pp.26-41
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• 2020

In order to culture a life for the physiological and ecological research of the meiofauna, this study aimed to identify the most ideal condition in which the meiofauna can be cultured within a laboratory by setting various environmental conditions. The sediment deposits and seawater were collected from the intertidal zone in Mallipo of the west coast. A aquarium in which the internal environment can be controlled by constantly maintaining the temperature and humidity was fabricated and the culture experiments of the collected meiofauna were conducted together with the sea water and sediment deposits collected. The experiment 1 was conducted after establishing the similar environment as the collecting location. Under the same condition as the experiment 1, the experiment 2 verified a difference between when live foods were supplied and were not. In the experiment 3, the changes in the meiofauna colony were checked according to with or without light and live foods. In the results of culturing experiments, the habitat density and the number of appeared classification groups of the meiofauna colony were relatively higher both in the water tank with supplying the live foods and under the condition of having light in 12-hour cycle than those in the aquarium without live foods and under no light condition. In addition, the habitat density of meiofauna cultured within a laboratory exhibited relatively higher value than that under the natural state.

• 한국해양학회지
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• v.30 no.3
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• pp.147-162
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• 1995

The circulation due to tidal current and river discharge, and the associated suspended suspended sediment transport in macrotidal Keum Estuary, were studied through a series of field measurements of tidal currents and suspended sediment concentration at three anchored stations from 1990 through 1992. From the measurements, the following results were obtained. At the seaward entrance of the estuary, the veritical profiles of the ebb and flood currents were almost symmetric. At the southern channel the flood current was dominant in the whole water column, but in the northern channel the ebb current was dominant in the surface and bottom layers and the flood current was dominant in the intermediate layer. The maximum velocity of the tidal current in the southern channel was 174 cm/s during flood tide in the intermediate layer. The maximum velocity, 148 cm/s in the northern channel also appeared during flood tide in the intermediate layer. However, in the surface and bottom layers, the maximum velocities were 110.6 cm/s during ebb tide and 92.1 cm/s during flood tide, respectively. The type of the Keum Estuary can be categorized to 'Type 3' of Hansen and Rattray's scheme. The water column of the estuary during the flood tide becomes stratified, and after high water the ebb current reduces the density difference and the water column becomes turbulent. The lower layer of the water column is generally turbulent. The largest sediment flux 20.61 ton/s was found in the southern channel during flood current in the lowest river discharge (May, 1991), while the smallest flux, 0.65 ton/s in the northern channel in the lowest tidal range (July, 1992). The stronger bottom shear velocity for the present study area seems to erode the bottom sediments during the flood tide, and the relatively long duration of the ebb tide to transport the suspended sediments. Under normal river discharge conditions, the suspended sediments are transported mainly through the southern channel. However, under high river discharge condition the suspended sediment transport is dominant through the northern channel.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.6 no.2
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• pp.112-119
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• 2003

Purpose: Helicobacter pylori infection is thought to be correlated with iron-deficiency anemia (IDA) at puberty. The H. pylori feoB gene, a high-affinity ferrous iron transporter, plays a central role in iron acquisition. This study aims to analyze the H. pylori feoB status according to the presence of antral gastritis with or without IDA. Methods: Fourteen H. pylori-positive patients aged from 10~18 years were categorized into subgroups based on the presence or absence of IDA. Eight patients had IDA, and the other six showed normal hematological findings. Genomic DNA was isolated from cultured H. pylori. Five sets of primers were used for PCR amplification of the feoB gene. The feoB region, 1.93 kb, was generated by linking of the PCR products and sequenced. The feoB gene sequences of H. pylori J99 and 26695 were used to compare with the clinical strains. Sequence comparisons of the feoB regions between the IDA (+) and (-) groups were performed. Results: Sequence analysis of the complete coding region of the feoB revealed 16 sites of polymorphism. Among these, 3 polymorphisms-Glu/Thr254Ala, Ile263Val, and Lys511Gln - were indigenous to Korean strains. Although statistically significant differences appear in 4 sites between IDA (+) and (-), the number of specimens are too low to assess the real differences. Conclusion: The 4 polymorphisms in the feoB gene seem to be related with IDA, but it is unclear yet because of small number of study strains. Further studies are required to prove the correlation of IDA and H. pylori infection.

• Weed & Turfgrass Science
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• v.2 no.4
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• pp.413-420
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• 2013

The climate change affects the growth and development of weeds as well as the outbreak of weeds. Especially, the occurrences of problematic paddy weeds due to climate change might cause the difficulties in weed control. This study therefore, investigated the current dominance and distribution of paddy weeds. As a result of the study on paddy weeds in northern Gyeonggi-do, there were total of 65 taxonomy groups including 23 family, 41 genus, 57 species, 7 subspecies and 1 variety. Among all the plants, 46 species were annual plants and 16 were perennial plants. Echinochloa crus-galli was the highest in importance analysis and the followings were in order of Ludwigia prostrate and Lemna paucicostata. The similarity of different paddy weeds in different regions observed through TWINSPAN analysis was distinguished by Fimbristylis miliacea, Rotala indica and Cyperus flaccidus. Regional differences shown in CCA analysis using weed species and soil environment revealed that Gimpo-si and Namyangju-si has difference soil and weeds, which are features that distinguished them from other regions. In northern Gyeonggi-do the result of paddy weed research showed the interregional difference not in dominant weeds but in distribution species.

• The Korean Journal of Ecology
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• v.25 no.2
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• pp.75-82
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• 2002

Saussurea chabyoungsanica was recorded in new species by Lim Hyoung Tak in 1997. In order to understand the entity of new species, we investigated the new distribution sites, vegetation structure and soil environmental factors. Additionally discovered distribution sites of S. chabyoungsanica were Manduckbong, Mt. Sukbyoung, Mt. Duckhang, and Sukgaejae, which were located on ridge of the Taebaek mountains. Those sites are typical limestone zones of Korea and among them Sukgaejae belongs to lower great limestone area and Manduckbong, Mt. Sukbyoung and Mt. Duckhang belong to uper great limestone area. According to the result of phytosociological study, plant communities of S. chabyoungsanica were classified by 1 Community group, 4 Communities and 2 Subcommunities; Carex humilis var. nana - Saussurea chabyoungsanica Community group in wide sense Quercus mongolica Community group, Lespedeza maximowiczii- Saussurea chabyoungsanica Community, Galium kinuta - Saussurea chabyongsanica Community, Saliva chanryonica - Saussurea chabyoungsanica Community, Zabelia coreana - Saussurea chabyoungsanica Community. Environmental factor analysis of habitat showed that the distribution site of S. chabyoungsanica was ridge of North aspect and displayed pH 7∼8 typical of limestone. Soil moisture content was high, whereas organic matter content was low. Considering its high occurrence in sites of 1∼10cm in soil depth, and of 30∼45% in relative light intensity, major distribution sites were outcrops and boundaries between shrubland and forest. After community division by vegetation structure in habitat of S. chabyoungsanica, we investigated characters of soil environment by community. As a result of PCA analysis of soil sample by community, it was possible to divide community by characters of soil environmental factor. The cumulative value of contribution rate represented in second dimension space was 73% and the major factors for that value were soil texture, organic matter content and field capacity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.157-163
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• 2016

BIM is currently applied in some domestic construction firms, but it is not being actively utilized due to changes in working environments and qualms about new studies. In order to utilize a BIM model in the design phase, process information is needed during construction, but the input system and utilization method of the process information's state are not complete. Therefore, we propose a BIM template for construction progress management that can show basic BIM information as the construction progresses in an easy and convenient way. This method will facilitate the adoption of BIM and enhance the productivity of construction companies. To this end, we designed a progress explorer for step-by-step progress and work schedules, and we generated three-dimensional views and a progress list by applying unit information (primary units, part units, and detail units) of the work breakdown structure (WBS) to the parameters. To use the BIM template, work progress information is input to the BIM modeling objects through Dynamo. We also used Dynamo for quick and easy calculation of the quantity of materials needed for construction work. To test the BIM template, we applied it to an actual project and evaluated its visibility and a progress list. The results showed that the proposed BIM template facilitates progress management of a project and can thus facilitate the adoption of BIM and improve the productivity of construction companies.

• Journal of the Korea Organic Resources Recycling Association
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• v.20 no.4
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• pp.61-74
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• 2012

Industrial complexes in Korea have been vigorously established by economic development plan and development policy of industry in 1960s. Recently, Korean government has promoted Eco Industrial Park (EIP) project to recycle by-products and wastes in industrial park In this study, we analyzed the physical and chemical properties for the sludges discharged from A industrial complex. And we investigated the economic feasibility and environmental impact of sludge to energy facilities. The analysis results indicated that the petrochemical industry were 92% in sludge production, the highest treatment amount was landfill, followed by incineration and recycling and then ocean disposal. Wastewater sludge and process sludge samples are collected and analyzed to use as basic data on economic feasibility and environmental impact. Weighted average heating value of sludge samples was 3,891kcal/kg. Based on this data, installation and operation costs, operation returns of operating the drying facility are estimated, compared with cogeneration facility. And this study examines how the payback period of each simulation(total 8 case) with the important parameter changes. As a result, it was found that what needs the shortest payback period is 3years with connection of drying facility and cogeneration facility based on the government's financial subsidy system.

• Journal of Food Hygiene and Safety
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• v.28 no.2
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• pp.99-107
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• 2013

Food contaminants are an emerging issue because food is highly influential to human health. Delphi survey was performed to establish the plan for effective management of food contaminants. Fifty experts from academia, research institute, government and food industries on food safety and policy participated in this study. From open-end questions 161 topics were collected and classified into five areas and 42 topics as the first round. The five areas were 'the integrated management system on food contaminants', 'safety management of food contaminants derived from environment', 'safety management of natural toxins contaminated on foods', 'safety management of hazardous substances produced during food processing' and 'construction of cooperative system and public relationship'. At the second round, after analyzing the replies (30/50 replied) the preliminary order was obtained and it was confirmed at the third round (24/30 replied). We suggest the order of priority for required research area of food contaminants considering the importance and urgency of the research.

• Weed & Turfgrass Science
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• v.4 no.3
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• pp.236-242
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• 2015

We surveyed the distribution of exotic weeds in the 141 crop fields of Jeju island. The exotic weeds were summarized as 66 taxa including 18 families, 50 genera, 64 species and 2 varieties. In winter crop fields there were 45 species of exotic seeds in 18 families, in summer crop fields 50 species in 16 families, and in perennial crop fields 39 species in 17 families. Total exotic weeds were classified to 39.4% of summer annuals, 36.4% of winter annuals, 7.6% of summer and winter annuals, and 16.7% of perennials. The ratio of summer annuals were high in the summer crop fields. Compositae was dominant family, followed by Gramineae, Malvaceae and Solanaceae. Malvaceae did not appear in perennial crop fields. Dominant exotic weeds in winter crop fields were Chenopodium album, Amaranthus viridis, Senecio vulgaris and Coronopus didymus, in summer crop fields, Chenopodium album, Amaranthus viridis, Senecio vulgaris and Sonchus oleraceus and in perennial crop fields, Conyza sumatrensis, Gnaphalium calviceps and Senecio vulgaris. The dominant exotic weeds in the crop fields of Jeju island were Chenopodium album, followed by Amaranthus viridis, Senecio vulgaris, and Conyza sumatrensis. This information could be useful for establishment of exotic weed control methods in Jeju island.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.5
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• pp.2045-2053
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• 2012

The primary purpose of this paper is to identify the cognition of the convergence human resource for firms. For this purpose, Data have been collected from 110 firms in Daejeon city and studied the convergence human resource which recognized by firms on the company competitive power level. The results of this empirical studies are summarized as fellows. We classified in company competitive power as leading chaser, innovators and late chaser. In the talent, leading chasers demanded the total designer, problem solver and insighter, innovators demanded the total designer, problem solver and specialist, and late chasers demanded the traditional humanity. In technology management, all group think important fields. In the demanding forecasting for the market and technologies, leading chasers and innovators demanded the CEO, R&D researcher and a middle manager as the important position. For this education, they demanded the convergence ability of other technologies, the up-to-date abilities of product and technology and the understandings of market needs. In the convergence talent or leader, leader chaser and innovator demanded the specialist who attempted to combine others industries, who know well in technology and management, and the specialist who attempted to combine others technologies. But, late chaser demanded the specialist who attempted to combine others industries.