• Journal of Korea Port Economic Association
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• v.23 no.1
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• pp.61-73
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• 2007

Creating more efficient and effective intermodal transportation service in Northeast range is a critical issue because of more increased trade volume & demand for intermodal service in the world market and geographical barriers associated with goods transportation, especially in Korea, China and Japan. This study examines the possibility of Rail-ferry introduction and possible route in Northest area which can provide each country mutual economical and logistical satisfaction. But, this study requires more empirical and concrete examination based on the cost & benefit analysis.

• Journal of Korea Spatial Information System Society
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• v.9 no.3
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• pp.25-33
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• 2007

The local governments of major cities in Korea are giving focus on public transportation to reduce congestion and improve accessibility in city areas. In this regards, the proper measurement of accessibility is now a key policy requirement for reorganizing the public transport network. Public transport routing problems, however, are considered to be highly complicated since a multi-mode travel generates different combinations of accessibility. While most of the previous research efforts on measuring transport accessibility are found at zone-levels, an alternative approach at a finer scale such as bus links and stops is presented in this study. We proposes a method to compute the optimal route choice of origin-destination pairs and measure the accessibility of the chosen modes combination based on topological configuration. The genetic algorithm is used for the computation of the journey paths, whereas the space syntax theory is used for the accessibility. This study used node-link data in GIS instead of axial lines which are manually drawn in space syntax. The resulting accessibilities of bus stops are calibrated by O-D survey data and the proposed process is tested on a CBD of Seoul.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.2
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• pp.147-150
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• 2020

Relatively pure YBCO was first synthesized by heating a mixture of metal carbonates at temperatures between 1,000 and 1,300 K, resulting in the reaction: 4BaCO₃+Y₂(CO₃)₃+6CuCO₃+(1/2_-x)O₂ → 2YBa₂Cu₃O_7-x+1/3CO₂. Modern syntheses of YBCO use the corresponding oxides and nitrates. The superconducting properties of YBa₂Cu₃O_7-x are sensitive to the value of x, i.e., its oxygen content. Only those materials with 0≤x≤0.65 are superconducting below Tc, and when x ~ 0.07, the material superconducts at the highest temperature, i.e., 95 K, or in the highest magnetic fields, i.e., 120 T and 250 T when B is perpendicular and parallel to the CuO₂ planes, respectively. In addition to being sensitive to the stoichiometry of oxygen, the properties of YBCO are influenced by the crystallization methods applied. YBCO is a crystalline material, and the best superconductive properties are obtained when crystal grain boundaries are aligned by careful control of annealing and quenching temperature rates. However, these alternative methods still require careful sintering to produce a quality product. New possibilities have arisen since the discovery of trifluoroacetic acid, a source of fluorine that prevents the formation of undesired barium carbonate (BaCO₃). This route lowers the temperature necessary to obtain the correct phase at around 700℃. This, together with the lack of dependence on vacuum, makes this method a very promising way to achieve a scalable YBCO bulk.

• Applied Microscopy
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• v.31 no.2
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• pp.199-206
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• 2001

In 1980s, the fragmentation or subdivision of protein deposits at the periphery of protein storage vacuole was suggested as the only route of PB development in pea cotyledon cells. Since then, other independant processes such as terminal dilation , transformation and de novo development have been discussed as alternative routes for PB development, and today, these multiple mechanisms of PB development are accepted as a result of active investigations. For analysis of the protein accumulations in the ER cisternae during seed development, immunocytochemical gold labellings were applyed on the single cells separated by enzymatic digestion from cotyledon tissue. Anti-legumin labellings at the early stage, and anti-vicilin labellings at the intermediate stage were observed on the protein-filled ER. The $\alpha-Tip$, which is the ER retention protein, was labelled somewhat at late stage, and PPase, a sort of tonoplast membrane protein, was labelled at early stage.

• Journal of Applied Biological Chemistry
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• v.60 no.4
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• pp.333-338
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• 2017

Cellulosic alcohol fermentation has recently gained more attention in the production of ethanol, butanol, and 2,3-butanediol. However, it was revealed that the process had several hurdles, such as, an expensive cost for biomass decomposition to yield fermentable sugars and a production of byproduct lignin. As an alternative for the process through biomass saccharification, the alcohol production through syngas from biomass has been studied. In this study, we reviewed acetogen and its central metabolic pathway, Wood-Ljungdahl route, capable of utilizing syngas. Furthermore, the metabolic engineering strategies of acetogen for bio-alcohol production from syngas was also reviewed with a brief perspective.

• Journal of Korean Society for Geospatial Information Science
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• v.19 no.3
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• pp.67-74
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• 2011

In recent years, with increasing utilization of mobile devices such as smartphones, the need for PNS(Pedestrian Navigation Systems) that provide guidance for moving pedestrians is increasing. For the navigation services, road network is the most important component when it comes to creating route and guidance information. In particular, pedestrian network requires modeling methods for more detailed and vast space compared to road network. Therefore, more efficient method is needed to establish pedestrian network that was constructed by existing field survey and manual editing process. This research proposed a pedestrian network creation method appropriate for pedestrians, based on CNS(Car Navigation Systems) data that already has been broadly constructed. Pedestrian network was classified into pedestrian link(sidewalk, side street, walking facility) and openspace link depending on characteristics of walking space, and constructed by applying different methodologies in order to create path that similar to the movements of actual pedestrians. The proposed algorithm is expected to become an alternative for reducing the time and cost of pedestrian network creation.

• Journal of Pharmacopuncture
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• v.18 no.3
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• pp.32-41
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• 2015

Objectives: Condurango (Gonolobus condurango) extract is used by complementary and alternative medicine (CAM) practitioners as a traditional medicine, including homeopathy, mainly for the treatment of syphilis. Condurango bark extract is also known to reduce tumor volume, but the underlying molecular mechanisms still remain unclear. Methods: Using a cervical cancer cell line (HeLa) as our model, the molecular events behind condurango extract's (CE's) anticancer effect were investigated by using flow cytometry, immunoblotting and reverse transcriptase-polymerase chain reaction (RT-PCR). Other included cell types were prostate cancer cells (PC3), transformed liver cells (WRL-68), and peripheral blood mononuclear cells (PBMCs). Results: Condurango extract (CE) was found to be cytotoxic against target cells, and this was significantly deactivated in the presence of N-acetyl cysteine (NAC), a scavenger of reactive oxygen species (ROS), suggesting that its action could be mediated through ROS generation. CE caused an increase in the HeLa cell population containing deoxyribonucleic acid (DNA) damage at the G zero/Growth 1 (G0/G1) stage. Further, CE increased the tumor necrosis factor alpha ($TNF-{\alpha}$) and the fas receptor (FasR) levels both at the ribonucleic acid (RNA) and the protein levels, indicating that CE might have a cytotoxic mechanism of action. CE also triggered a sharp decrease in the expression of nuclear factor kappa-light-chain-enhancer of activated B cells ($NF-{\kappa}B$) both at the RNA and the protein levels, a possible route to attenuation of B-cell lymphoma 2 (Bcl-2), and caused an opening of the mitochondrial membrane's permeability transition (MPT) pores, thus enhancing caspase activities. Conclusion: Overall, our results suggest possible pathways for CE mediated cytotoxicity in model cancer cells.

• Journal of Microbiology and Biotechnology
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• v.30 no.11
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• pp.1729-1738
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• 2020

Salmonellosis is a form of gastroenteritis caused by Salmonella infection. The main transmission route of salmonellosis has been identified as poorly cooked meat and poultry products contaminated with Salmonella. However, in recent years, the number of outbreaks attributed to contaminated raw produce has increased dramatically. To understand how Salmonella adapts to produce, transcriptomic analysis was conducted on Salmonella enterica serovar Virchow exposed to fresh-cut radish greens. Considering the different Salmonella lifestyles in contact with fresh produce, such as motile and sessile lifestyles, total RNA was extracted from planktonic and epiphytic cells separately. Transcriptomic analysis of S. Virchow cells revealed different transcription profiles between lifestyles. During bacterial adaptation to fresh-cut radish greens, planktonic cells were likely to shift toward anaerobic metabolism, exploiting nitrate as an electron acceptor of anaerobic respiration, and utilizing cobalamin as a cofactor for coupled metabolic pathways. Meanwhile, Salmonella cells adhering to plant surfaces showed coordinated upregulation in genes associated with translation and ribosomal biogenesis, indicating dramatic cellular reprogramming in response to environmental changes. In accordance with the extensive translational response, epiphytic cells showed an increase in the transcription of genes that are important for bacterial motility, nucleotide transporter/metabolism, cell envelope biogenesis, and defense mechanisms. Intriguingly, Salmonella pathogenicity island (SPI)-1 and SPI-2 displayed up- and downregulation, respectively, regardless of lifestyles in contact with the radish greens, suggesting altered Salmonella virulence during adaptation to plant environments. This study provides molecular insights into Salmonella adaptation to plants as an alternative environmental reservoir.

• Nuclear Engineering and Technology
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• v.49 no.4
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• pp.721-733
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• 2017

When temporary spent fuel storage pools at nuclear power plants reach their capacity limit, the spent fuel must be moved to an alternative storage facility. However, radioactive materials must be handled and stored carefully to avoid severe consequences to the environment. In this study, the risks of three potential accident scenarios (i.e., maritime transportation, an aircraft crashing into an interim storage facility, and on-site transportation) associated with the spent fuel transportation process were analyzed using a probabilistic approach. For each scenario, the probabilities and the consequences were calculated separately to assess the risks: the probabilities were calculated using existing data and statistical models, and the consequences were calculated using computation models. Risk assessment software was developed to conveniently integrate the three scenarios. The risks were analyzed using the developed software according to the shipment route, building characteristics, and spent fuel handling environment. As a result of the risk analysis with varying accident conditions, transportation and storage strategies with relatively low risk were developed for regulators and licensees. The focus of this study was the risk assessment methodology; however, the applied model and input data have some uncertainties. Further research to reduce these uncertainties will improve the accuracy of this model.

• Journal of Korean Society of Transportation
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• v.28 no.5
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• pp.131-139
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• 2010

The transport mode choice problem is to determine which of the alternative transport modes connecting an origin and destination will be used by a traveler. Most of the research relating to transport mode choice have mainly been focused on modeling, properties, and applications of the model, but rarely were concerned with equilibrium among the modes. This paper proves the equilibrium among the modes by using a logit mode choice model, and then verifies it with the Korean Transport Database (KTDB). In order to obtain such an equilibrium, this paper also presents a solution algorithm based on the fixed point theorem. The algorithm was tested with an example and confirmed the equilibrium solution.