• Journal of the Korean Society for Precision Engineering
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• v.29 no.4
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• pp.357-366
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• 2012

To schedule a Reconfigurable Manufacturing Cell (RMC), reconfiguration and setting decisions should be made first. Those decisions, together with characteristics of production orders, affect attainable performance of a system. So an integrative approach is required considering all decisions and characteristics rather than dealing with each of them separately. Pallet-fixture allocation, as a decision problem in setting, which determines the number of pallets to be equipped with each fixture type to produce different types of products, has rarely been investigated. In this study, several pallet-fixture allocation rules are proposed including both simple and novel ones. Then system performance is investigated through various combinations of setting and scheduling decisions (rules) for given system configurations and production orders, via simulation. The result shows that one of proposed pallet-fixture allocation rules which considers both configuration and order characteristic outperforms the others, justifying the necessity of an integrative approach in the RMC operation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.4
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• pp.507-528
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• 2015

The Fish Collection Project collected 356 fish species from the Southern Sea of Korea during 2010-2012, 55 more than previously collected. The fishes belonged to 3 classes, 29 orders and 128 families. The 5 dominant orders, Perciformes, Scorpaeniformes, Pleuronectiformes, Tetraodontiformes, and Clupeiformes, accounted for ~80% of the identified species. Additionally, 126 species were collected from the Southern Sea for the first time, while 85 species that had been found in previous collections were not seen. The species variety of fish in the Southern Sea may be influenced by its unique oceanographic conditions such as increased water temperatures in coastal areas, so regular surveys would assist our understanding of the fish community. We suggest that various collection methods, including diving, be used to collect fish species inhabiting rocky shore or deep-sea areas, where commercial fishing gear is difficult to deploy.

• Journal of Korean Society of Forest Science
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• v.101 no.4
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• pp.703-709
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• 2012

We studied the community fluctuations of benthic macroinvertebrates of forest fired area in Samcheok-si from 2001 to 2009. Total collected macroinvertebrates species were 18 belonging to 14 families, 8 orders, 3 classes, and 2 phyla in 2001, and 70 belonging to 40 families, 15 orders, 7 classes and 5 phyla in 2009 (9 years after the forest fire). During the first four years after the forest fire, dipteran insects were dominant, but after then, ephemeropteran insects have increased in abundance and richness. As time elapsed from the fire, dominance indices were decreasing, while species diversity, richness and species evenness indices were increasing.

• Journal of Distribution Science
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• v.14 no.10
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• pp.153-164
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• 2016

Purpose - In general, large companies have larger organizations, funds, and systems to provide more effective and efficient services in the market. However, development needs to support the livelihood of ordinary citizens who work for small businesses as well. This research suggests that a new distribution channel, called a "foothold style Kosa mart," that cooperates jointly with a distribution center and a large discount mart can provide direct solutions to small and mid-size distributors. This new distribution channel can achieve a limited type of "Nadle shop (small supermarket) foster project" related to building a joint distribution center and improvement in wholesale supply. Research design, data, and methodology - Data about the Korea distribution situation, the Nadle stores, and the logistics centers were collected from literature, Statistics Korea, journals, and reports. Specifically, we investigated information about Kosa Mart and Nadle stores. We focused on the redesign of the distribution center for the Nadle store. Results - The Kosa Mart distribution center now includes 18 warehouses, and has been handling 2000-3000 items. Most of the warehouses have been simply designed and items loaded and stored without refrigeration; thus, it is possible to store only products of certain manufactured goods. The current logistics center has no wholesale function because it failed to resolve the joint purchasing and product supply issues of competitively priced products. Conclusions - This study aimed to identify ways to strengthen the competitiveness of small- and medium-sized retailers. A Kosa Mart redesign aims to unifying the logistics center, stores, and customers. First, the joint wholesale logistics system, equipped with an integrated ordering system, needs to process customer orders and store orders at the same time. Second, excellent small business product development has to connect with production. Third, the store composition needs to support a shipping hub. Fourth, the Mart differentiates itself from convenience store goods by supplying regional and specialized products to customers. Fifth, a service buying agent and direct transactions between producers and consumers need to be established, and exhibits and displays of goods need to be improved.

• 한국균학회소식:학술대회논문집
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• 2014.10a
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• pp.21-21
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• 2014

The importance of utilizing biological resources has become magnified and it has been a big issue to share the benefit among nations as Nagoya Protocol began in 2010. This study was conducted to research the diversity and distribution of wild mushrooms, and to survey the traditional mushroom knowledge of the people in Jejudo which is a volcanic island having a distinctive climate and forest environment. The research sites were Dongbaekdongsan, Keuneonggot, Hallasan National Park, Muryeongarioreum, Saryeonisupgil and other important area where mushrooms are growing spontainously in Jejudo. A total of 511 species comprising 2 phylums, 8 classes, 20 orders and 74 genera were identified from 1600 specimens collected from 2006 to 2012. In previous studies, a total of 561 species comprising 69 families and 99 genera were investigated. As a result, a total of 755 species comprising 23 orders, 87 families and 263 genera were documented in Jejudo. In this study, 137 species were newly identified as unrecorded species in Jejudo and 9 species, Amanita gemmata, Tricholoma aurantiipes, Panellus violaceofulvus, Leucopaxillus septentrionalis, Bondarzewia montana, Psilocybe argentipes, Boedijnopeziza insititia, Sarcoscypha occidentalis for. occidentalis and Morchella patula var. semilibera were the first record for Korea. Also, 7 species, Amanita gemmata, Tricoloma aurantiipes, Panellus violaceofulvus, Leucopaxillus septentrionalis, Boedijnopeziza insititia, Sarcoscypha occidentalis for. occidentalis and Morchella patula var. semilibera were known as only growing in Jejudo. The traditional knowledge was collected from visiting and questionnaire survey in 50 villages in Jejudo. A total of 23 mushrooms were found in which 12 species were used for food, 2 species were poisonous, 6 species were medicinal, 2 species were used for folk religion and 3 species were used for play purposes. Macrolepiota procera was the most commonly used as an edible mushroom and Chlorophyllum neomastoidea was the most well known poisonous mushroom. Also, 267 cases of traditional knowledge about using mushrooms as a food and medicine were collected. This study has significance for supplementing previous studies about distribution of wild mushrooms in Jejudo and documenting unrecorded species in Korea. Also, it is valuable by providing important data of traditional knowledge for using mushrooms since old times.

• BMB Reports
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• v.37 no.2
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• pp.199-205
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• 2004

The six lumbrokinase fractions (F1 to F6) with fibrinolytic activities were purified from earthworm Lumbricus rubellus lysates using the procedures of autolysis, ammonium sulfate fractionation, and column chromatography. The proteolytic activities on the casein substrate of the six iso-enzymes ranged from 11.3 to 167.5 unit/mg with the rank activity orders of F2 > F1 > F5 > F6 > F3 > F4. The fibrinolytic activities of the six fractions on the fibrin plates ranged from 20.8 to 207.2 unit/mg with rank orders of F6 > F2 > F5 > F3 > F1 > F4. The molecular weights of each iso-enzyme, as estimated by SDS-PAGE, were 24.6 (F1), 26.8 (F2), 28.2 (F3), 25.4 (F4), 33.1 (F5), and 33.0 kDa (F6), respectively. The plasminogen was activated into plasmin by the enzymes. The optimal temperature of the six iso-enzymes was $50^{\circ}C$, and the optimal pH ranged from pH 4-12. The four iso-enzymes (F1-F4) were completely inhibited by PMSF. The two enzymes (F5 and F6) were completely inhibited by aprotinin, TLCK, TPCK, SBTI, LBTI, and leupeptin. The N-terminal amino acid (aa) sequences of the first 20 to 22 residues of each fraction had high homology. All six isoenzymes had identical aa residues 2-3 and 13-15. The N-terminal 21-22 aa sequences of the F2, F3, and F4 isoenzymes were almost the same. The N-terminal aa sequences of F5 and F6 were identical.

• Journal of The Korean Astronomical Society
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• v.24 no.2
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• pp.191-215
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• 1991

We have compared the column densities of $H_2CO$, $^{13}CO$, $C^{18}O$, $^{12}CO$, CS, and $HCO^+$ to the visual extinctions derived from star counts in eight dark clouds, L1317, B1, L1551, L1535, L1544, L134, L134N, and B335. We examined the degree of correlation between molecules and extinctions. The contours of $^{13}CO$, $H_2CO$, and CS distributions show an excellent coincidence with those of the visual extinction. Even though the plots of molecule brightness temperature or column density as a function of the visual extinction show a considerable scatter, a good correlation is found between the two quantities. The turnover of the ratios of $^{13}CO$ and $H_2CO$ column densities to the visual extinction at high extinctions observed in several clouds is not apparent in this work. The ratios seem to maintain constant values within the range of $A_V$ we studied. The slopes of the relations between the molecule column density and extinction, and the threshold values of extinction for detection of molecules are comparable to the other works. The cause of the slope difference is discussed. We derived, for the first time, the relations of CS and $HCO^+$ column densities and the visual extinction. The ratio of CS column density to extinction is at least two orders of magnitude lower than the mean value for $^{13}CO$, but the threshold for detection of CS is comparable to that of $^{13}CO$. The ratio of the $HCO^+$ column density to extinction is one to two orders of magnitude lower than the mean ratio for $H_2CO$.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.42 no.1
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• pp.33-40
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• 2019

This study focuses on a job-shop scheduling problem with the objective of minimizing total tardiness for the job orders that have different due dates and different process flows. We suggest the dispatching rule based scheduling algorithm to generate fast and efficient schedule. First, we show the delay schedule can be optimal for total tardiness measure in some cases. Based on this observation, we expand search space for selecting the job operation to explore the delay schedules. That means, not only all job operations waiting for process but also job operations not arrived at the machine yet are considered to be scheduled when a machine is available and it is need decision for the next operation to be processed. Assuming each job operation is assigned to the available machine, the expected total tardiness is estimated, and the job operation with the minimum expected total tardiness is selected to be processed in the machine. If this job is being processed in the other machine, then machine should wait until the job arrives at the machine. Simulation experiments are carried out to test the suggested algorithm and compare with the results of other well-known dispatching rules such as EDD, ATC and COVERT, etc. Results show that the proposed algorithm, MET, works better in terms of total tardiness of orders than existing rules without increasing the number of tardy jobs.

• Korean Journal of Medicinal Crop Science
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• v.27 no.3
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• pp.167-172
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• 2019

Background: Angelica acutiloba Kitagawa belongs to the flowering plant family Apiaceae. Its young leaves are consumed as a vegetable, and its roots have medicinal properties. This study was conducted to analyze the seed germination characteristics of A. acutiloba according to its ripening stages. Methods and Results: The seeds were harvested from a research farm managed by the Department of Herbal Crop Research, Rural Development Administration in 2018 and were divided into six groups according to their specific gravities. In particular, we studied the effect of harvesting periods and umbel orders on seed characteristics. The results showed that the rates of germination, emergence, and early growth improved as the specific gravity of the seeds increased. In addition, the germination rates of the seeds harvested in mid July and early August were significantly higher than those harvested in the other seasons, and the seeds obtained from the first floret had the greatest mass and weight. Conclusions: In this study, we demonstrated that it is possible to improve the germination rate by appropriate selection of seeds and harvesting period both of which are closely related to seed maturity.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.6
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• pp.624-633
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• 2020

In those day, Incheon and Busan local government are arguing about establishment of a maritime court. This study aims to develop a model that evaluates the priority orders for the establishment of maritime courts using maritime casualties counts based on the integrated ELECTRE-CRITIC-ISM technique, as well as to verify its usefulness in the establishment of maritime courts in Korea. For this purpose, a total of 22 ports, excluding nine ports where maritime accident data were integrated and managed among the 31 international trade ports, were matched with the jurisdiction of six alternative high courts. Second, the CRITIC method was used to calculate the weights of the number of maritime casualties during a 5-year period that were evaluation factors and combine with the ELECTRE method. Finally, the ELECTRE&ISM method was used to analyze the concordance and discordance between high courts and evaluate the priority orders considering the fluctuations of maritime casualties counts. As the final evaluation result considering the mean values in fluctuations of maritime casualties counts, the Busan High Court ranked first, the Gwangju high court second, the Seoul high court third, the Daejeon and the Daegu high court forth (equal), and the Suwon high court sith. Therefore, it is necessary to preferentially establish a maritime court in the jurisdiction of the Busan High Court.