• Journal of Navigation and Port Research
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• v.38 no.6
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• pp.567-575
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• 2014

In recent times, an obvious strategy in liner shipping markets that has come to the fore is slow steaming. Nowadays, most liner shipping companies have decelerated the voyage speed to 15-18 knots on major routes, and some leading liner shipping companies have a plan to reduce it to below 15 knots. Slow steaming is helpful in reducing the operating cost and the amount of greenhouse-gas emissions on a single vessel with lower fuel consumption. However, it also creates various negative effects such as the opportunity cost, additional fixed costs and an in-transit inventory cost on a loop. Hence, the net operating cost on a loop is changing dynamically due to the changes of voyage speed based on various slow steaming effects. The aim of this study is to analyze the slow steaming effects in the liner shipping, and to find the best voyage speed that minimizes the operating cost on a loop. Moreover, this study suggests the recommendable strategy for liner shipping companies. To achieve the aim of this study, a simulation model has been designed using System Dynamics.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.12
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• pp.1166-1176
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• 2011

The prospect in opening the arctic trade transportation route on a year-round basis offers vast opportunity of exploring untapped resources and shortened navigational routes. In addition, the environment's remoteness and lack of technical experiences remains a big challenge for the maritime industry. With this, engine designers and makers are continually investigating, specifically optimizing propulsion shafting system design, to meet the environmental and technical challenges of the region. The International Association of Classification Society, specifically machinery requirements for polar class ships(IACS UR13), embodies the propulsion shafting design requirements for ice class vessels. However, the necessity to upgrade the various features of the unified rules in meeting current polar requirements is acknowledged by IACS and other classification societies. For the polar class propulsion shafting system, it is perceived that the main source of excitation will be the propeller - ice load interaction. The milling - and the impact load, in addition to the load cases interpreted by IACS, contribute greatly to the overall characteristic of the system and due considerations are given during the propulsion design stage. This paper will expound on the excitation load estimation factors affecting the dynamic response of the different propulsion shafting system design. It is anticipated that detailed understanding of these factors will have a significant role during propulsion shafting design in the future.

• Cross-Cultural Studies
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• v.29
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• pp.177-199
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• 2012

Nowadays migrations between the countries are getting each day more active and a mixture of people with different cultural backgrounds strengthens the hybridism, whereupon the point of view on the migration of Koreans has been changed from a diasporan perspective to an transnational one. The expansion of the transnationalism affects the identity of the subsequent generations of the immigration giving way to a psychologically deterritorialized social identity, which is an important consideration in the study of subsequent generations of the immigration. This study examined the Korean immigration history and the current status of the Korean community in Spain since the 1960s. The early immigrants like fishing vessel crew members, instructors of Taekwondo, chicken sexers who, despite the limits of foreigners in Spain, went to find out the source of life with no hesitation, overcame the difficulties of the early settlers and finally managed to achieve local success. Current history of immigration that began in the mid-1960s went through the maturity during the 1970s and 80s and the Koreans in Spain these days, who have undergone differentiation in the occupational structure because of the crisis of pelagic fisheries, face new challenges due to changes in the environment of the country they reside. The Korean community is regarded as an 'exemplary minority group (Model Minority)' even though it is a minority group in number. Now that the interest for overseas Koreans is higher than ever at home and abroad, due to the economic growth of the Republic of Korea, the spread of its cultural influence -the Korean Wave as proof-, and the overseas Koreans suffrage conducted, the research of the Korean residents in Spain will be important as an advanced research of an unexplored field, as well as an opportunity to broaden the horizons of the existing study area that has mainly dealt with major regions only.

• Design & Manufacturing
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• v.12 no.3
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• pp.5-12
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• 2018

Plastic containers which provides the opportunity to reduce transportation costs are lighter and less brittle than glass containers. As a results, efforts to replace glass with plastic are ongoing. The blow molding method is a typical approach in producing plastic containers. Single-stage injection blow molding (ISBM) is one of the blow molding methods. However, the difficulty in controlling the temperature during the injection molding process is considered its main disadvantage. In this study, ISBM process analysis of relatively thick walled containers such as cosmetic containers is carried out. The initial temperature distribution of the preform is deemed to be the most influential factor in the accuracy of blow molding for the thick vessel. In order to accurately predict this, all heat transfer processes of the preform are considered. The validity of this analytical procedure is verified by comparing the cross-sectional thickness with the actual product. Finally, the validated analytical method is used to evaluate the factors affecting the thickness of the final molded part. The ISBM analysis technique for thick walled vessels developed through this study can be used as an effective predictor for preform design and blow process.

• Journal of architectural history
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• v.21 no.1
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• pp.119-134
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• 2012

Balhae(698~926) was the ancient state which opened the Nambuk-guk period with the Unified Silla. But Balhae architecture began to included in the history of Korean architecture only about 15 years ago, such as the books written by Yun Jang-seop or Ju Nam-cheol. I discussed four issues related to Balhae architecture in this paper. First, I criticized the excavation report of 24 stones remains at Jiangdong in Duhua city, and I asserted the ondol site belonged to different period. Second, I also interpreted that the building found on the tombs no.13 and no.14, in the Longhai burial area in Helong city must be a wooden stupa. Third, Balhae played some important roles in the history of ondol. It developed Koguryeo ondol in terms of structure, gave an opportunity to the ruling class to adopt ondol for the first time, and passed the heating system down to the Jurchen, the ancestor of the modern Manchurian. Fourth, the Russian-Korean joint research team excavated seven building sites in Koksharovka 1 fortress from Russian territory these four years, and it is reasonable to assume the fortress was the center of Anbyeon-bu, one of 15 local government districts in Balhae. I guess this buildings were the royal shrine built by resisters after the fall of Balhae, and the vessel stands found there must be used for ancestral memorial ceremony inside them.

• Journal of Navigation and Port Research
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• v.26 no.4
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• pp.383-390
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• 2002

The time cost of ship end cargoes is one of the most important data for decision-making of port investment and operational efficiency. Studies in this area were initiated internationally by Goss and Mann in late 70's and also done in Korea 10 years ago using the same methodology as Goss. The main purpose of this paper is to revisit to estimate the time cost using updated data. The estimation was undertaken sampling data on various investment and operating costs by vessel from 205 vessels, comprising 47.5％ of the notional fleet in Korea as well as on cargoes from international trade statistics. Compared with the study of 10 years ago, major finding of this research is that time costs of liquid and dry bulk carriers have increased, in case of the former type, showing almost doubled cost increase. The increase is deemed to be caused by very expensive LNG carriers. Lowered social discount rate in this study compared with 10 years ago, in general, has mused the costs to stay at similar level to the previous study. Sensitivity tests were conducted using various social discount rates.

• Journal of Chest Surgery
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• v.44 no.1
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• pp.9-17
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• 2011

Background: A peripheral extracorporeal membrane oxygenator (p-ECMO) has been developed to support patients who are dying due to a serious cardiopulmonary condition. This analysis was planned to define the clinical situation in which the patient benefits most from a p-ECMO. Material and Methods: Between June 2007 and Aug 2009, a total of 41 adult patients used the p-ECMO. There were 23 males and 18 females (mean age $54.4{\pm}15.1$ years). All patients had very unstable vital signs with hypoxia and complex cardiac problems. We divided the patients into 4 groups. In the first group, a p-ECMO was used as a bridge to cardiac operation. In the second group, patients did not have the opportunity to undergo any cardiac procedures; nevertheless, they were treated with a p-ECMO. In the third group, patients mostly had difficulty in weaning from CPB (cardiopulmonary bypass) after cardiac operation. The fourth group suffered from many complications, such as pneumonia, bleeding, infections, and LV dysfunction with underlying cardiac problems. All cannulations were performed by the Seldinger technique or cutting down the femoral vessel. A long venous cannula of $DLP^{(R)}$ (Medtronic Inc, Minneapolis, MN) or $RMI^{(R)}$ (Edwards Lifesciences LLC, Irvine, CA) was used together with a 17~21 Fr arterial cannula and a 21 Fr venous cannula. As a bypass pump, a Capiox emergency bypass system ($EBS^{(R)}$; Terumo, Tokyo, Japan) was used. We attempted to maintain a flow rate of $2.4{\sim}3.0\;L/min/m^2$ and an activated clotting time (ACT) of around 180 seconds. Results: Nine patients survived by the use of the p-ECMO. Ten patients were weaned from a p-ECMO but they did not survive, and the remainder had no chance to be weaned from the p-ECMO. The best clinical situation to apply the p-ECMO was to use it as a bridge to cardiac operation and for weaning from CPB after cardiac operation. Conclusion: Various clinical results were derived by p-ECMO according to the clinical situation. For the best results, early adoption of the p-ECMO for anatomical correction appears important.

• Journal of radiological science and technology
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• v.36 no.2
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• pp.131-139
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• 2013

The aim of this study was to evaluate the variation which based on Celiac axis and SMA using by CT volume rendering images. 613 patients underwent abdominal CTA, there were 552 patients (99.05%, TypeI, II) with normal anatomical form and 61 (9.95%, Type III~XII) with variation. TypeI was 339(55.31%), Type II was 213 (34.74%), Type III was 18 (2.93%), Type IV was 12 patients (1.95%), Type V was 11 patient (1.79%), Type VI was 9 patients (1.46%), Type VII was 6 patients (0.97%), Type VIII was 1 patient (0.16%), Type IX was 1 patient (0.16%), Type X was 1 patient (0.16%), Type XI was 1 patient (0.16%), and Type XII was 1 patient (0.16%) into totally new types of variation. In conclusion, we could found 9 new types of variation by classifying based on celiac axis and superior mesenteric artery. These results were considered to be an important opportunity for a new vessel map.

• Journal of Life Science
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• v.14 no.5
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• pp.874-881
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• 2004

Angiogenesis has been implicated in progression of inflammation, arthritis, psoriasis, atherosclerosis as well as tumor growth and metastasis. Intensive studies have been carried out to develop a strategy for cancer treatment by blocking angiogenesis. During angiogenesis, endothelial proliferation and migration essentially occurs upon activation. In this study, we compared the expression profiles of human umbilical endothelial cells activated by incubating in vitro in the rich medium containing several growth factors, and non-activated ones. cDNA targets derived from total RNAs of HUVEC activated for 13 h in M199 medium containing endothelial cell growth supplement, 20% fetal bovine serum, and heparin, after reaching 70～80% confluency, or non-activated, were hybridized onto oligonucleotide microarrays containing 1,8864 genetic elements. Unsupervised hierarchical clustering analysis resulted in two subgroups on dendrogram exhibiting activated and non-activated HUVECs. We then extracted 122 outlier genes which were shown to be up-regulated or under-expressed by at least 2-folds in activated HUVECs. Among these, 32 annotated genes were up-regulated and 38 were down-regulated in activated HUVECs. Interestingly, genes involved in cell proliferation, motility, and inflammation/ immune response were up-regulated in activated HUVEC, whereas genes for cell adhesion or vessel morphogenesis/function were down-regulated. Unexpectedly, the expression of genes well-characterized as angiogenesis markers was not changed except Eph-B4, which was down-regulated about 4 folds. 52 unknown genes were also up- or down-regulated. Therefore, these results could provide an opportunity to targeting new vascular molecules for the development of anti-angiogenic molecules.