• Korean Journal of Construction Engineering and Management
• /
• v.15 no.4
• /
• pp.139-149
• /
• 2014

Lifeline service disruptions can have significant impacts on local community in the aftermath natural disaster. Although effective restoration strategies with accurate damage assessment are required, the internal complexity of lifeline networks and their interdependency makes the understanding restoration process of lifeline systems a difficult issue. Additionally, the limitations of previous research relating the influence assessment of lifeline to community disaster resilience, highlight the need for understanding of lifeline networks. Therefore, this paper presents an agent-based model to discover emergent behavior and evaluate the interdependency and resiliency in lifeline networks. This research will provide basic guideline of resource allocation in order to mitigate cascading failures of the post disaster restoration processes.

• Korean Journal of Construction Engineering and Management
• /
• v.19 no.3
• /
• pp.33-42
• /
• 2018

In the aftermath of an earthquake, seismic-damaged infrastructure systems loss estimation is the first step for the disaster response. However, lifeline systems' ability to supply service can be volatile by external factors such as disturbances of nearby facilities, and not by own physical issue. Thus, this research develops the bayesian model for probabilistic inference on common-cause and cascading failure of seismic-damaged lifeline systems. In addition, the authors present network robustness estimation metrics in the context of failure propagation. In order to quantify the functional loss and observe the effect of the mitigation plan, power and water supply system in Daegu-Gyeongbuk in South Korea is selected as case network. The simulation results show that reduction of cascading failure probability allows withstanding the external disruptions from a perspective of the robustness improvement. This research enhances the comprehensive understanding of how a single failure propagates to whole lifeline system performance and affected region after an earthquake.

• Journal of Oral Medicine and Pain
• /
• v.31 no.1
• /
• pp.1-16
• /
• 2006

The most important progress in diagnostic sciences is the increased sensitivity and specificity in diagnostic procedures due to the development of micromethodologies and increasing availability of immunological and molecular biological reagents. The technological advances led to consider the diagnostic use of saliva for an array of analytes and DNA source. The purpose of the present study was to compare DNA from saliva with those from blood and buccal swab, to evaluate diagnostic and forensic application of saliva, to investigate the changes of genomic DNA in saliva according to the storage temperature and period of saliva samples, and to evaluate the integrity of the DNA from saliva stored under various storage conditions by PCR analysis. Peripheral venous blood, unstimulated whole saliva, stimulated whole saliva, and buccal swab were obtained from healthy 10 subjects (mean age: $29.9{\pm}9.8$ years) and genomic DNA was extracted using commercial kit. For the study of effects of various storage conditions on genomic DNA from saliva, stimulated whole saliva were obtained from healthy 20 subjects (mean age: $32.3{\pm}6.6$ years). After making aliquots from fresh saliva, they were stored at room temperature, $4^{\circ}C$, $-20^{\circ}C$, and $-70^{\circ}C$. Saliva samples after lyophilization and dry-out procedure were stored at room temperature. After 1, 3, and 5 months, the same experiment was performed to investigate the changes in genomic DNA in saliva samples. In case of saliva aliquots stored at room temperature and dry-out samples, the results in 2 weeks were also included. Integrity of DNA from saliva stored under various storage conditions was also evaluated by PCR amplification analysis of $\beta$-globin gene fragments (989-bp). The results were as follows: 1. Concentration of genomic DNA extracted from saliva was lower than that from blood (p<0.05), but there were no significant differences among various types of saliva samples. Purities of genomic DNA extracted from stimulated whole saliva and lyophilized one were significantly higher than that from blood (p<0.05). Purity of genomic DNA extracted from buccal swab was lower than those from various types of saliva samples (p<0.05). 2. Concentration of genomic DNA from saliva stored at room temperature showed gradual reduction after 1 month, and decreased significantly in 3 and 5 months (p<0.05, p<0.01, respectively). Purities of DNA from saliva stored for 3 and 5 months showed significant differences with those of fresh saliva and stored saliva for 1 month (p<0.05). 3. In the case of saliva stored at $4^{\circ}C$ and $-20^{\circ}C$, there were no significant changes of concentration of genomic DNA in 3 months. Concentration of DNA decreased significantly in 5 months (p<0.05). 4. There were no significant differences of concentration of genomic DNA from saliva stored at $-70^{\circ}C$ and from lyophilized one according to storage period. Concentration of DNA showed decreasing tendency in 5 months. 5. Concentration of genomic DNA immediately extracted from saliva dried on Petri dish were 60% compared with that of fresh saliva. Concentration of DNA from saliva stored at room temperature after dry-out showed rapid reduction within 2 weeks (p<0.05). 6. Amplification of $\beta$-globin gene using PCR was successful in all lyophilized saliva stored for 5 months. At the time of 1 month, $\beta$-globin gene was successfully amplified in all saliva samples stored at $-20^{\circ}C$ and $-70^{\circ}C$, and in some saliva samples stored at $4^{\circ}C$. $\beta$-globin gene was failed to amplify in saliva stored at room temperature and dry-out saliva.

• Fire Science and Engineering
• /
• v.31 no.5
• /
• pp.53-62
• /
• 2017

Electric power which is the energy source of economy and industries requires long distance transportation due to regional difference between its production and consumption, and it is supplied through the multi-loop transmission and distribution system. Prior to its actual use, electric power flows through several transformations by voltage transformers in substations depending on the characteristics of each usage, and a transformer has the structure consisting of the main body, winding wire, insulating oil and bushings. A transformer fire that breaks out in substations entails the primary damage that interrupts the power supply to houses and commercial facilities and causes various safety accidents as well as the secondary economic losses. It is considered that causes of such fire include the leak of insulating oil resulting from the destruction of bottom part of bushings, and the chain reaction of fire due to insulating oil that reaches its ignition point within 1 second. The smoke detector and automatic fire extinguishing system are established in order to minimize fire damage, but a difficulty in securing golden time for extinguishing fire due to delay in the operation of detector and release of gas from the extinguishing system has become a problem. Accordingly, this study was carried out according to needs of active mechanism to prevent the spread of fire and block the leak of insulating oil, in accordance with the importance of securing golden time in extinguishing a fire in its early stage. A bushings fireproof structure was developed by applying the high temperature shape retention materials, which are expanded by flame, and mechanical flame cutoff devices. The bushings fireproof structure was installed on the transformer model produced by applying the actual standards of bushings and flange, and the full scale fire test was carried out. It was confirmed that the bushings fireproof structure operated at accurate position and height within 3 seconds from the flame initiation. It is considered that it could block the spread of flame effectively in the event of actual transformer fire.

• Food Science and Preservation
• /
• v.20 no.6
• /
• pp.791-797
• /
• 2013

This study was conducted to investigate the changes in the composition and microbiological properties of domestic sun-dried salt (white and gray salts) according to their collection time and production method. The results showed that the moisture contents of the white and gray sun-dried salts were 10.4~13.2% and 5.2~8.0%, respectively, and the sand contents were 0.1% and 0.2~0.3%, respectively, according to the month. Several samples exceeded the criteria of 15% moisture content and 0.2% sand content. The ash content and salinity of gray salt (below 85% and 90%, respectively) were higher than those of white salt (both below 80%). The total chloride contents of the salts collected in September and October were slightly lower than that of the others and exceeded the criteria of above 40%. In the case of mineral contents, there was no significant difference among the collection times because the analyses showed a marked deviation. The microbiological analysis showed that there was no significant difference among the production method, but the salt samples collected in September and October had relatively high detection rates of total aerobe, staphylococci, and halophilic bacteria.

• Journal of Korea Port Economic Association
• /
• v.27 no.1
• /
• pp.13-30
• /
• 2011

It's vital to establish the competitive comparative advantage as the competitions among global logistics companies have become fierce. The global companies, hence, must innovate their Port Hinterland to hub and spoke in a view of SCM. The Port Hinterland significantly affects its local economy and value added. The task of the Port Hinterland nowadays is to improve its efficiencies by utilizing logistics operations and services. The Korean government has planned to reduce the scale of the Port. The CCR and BCC matrices show that there are nine efficient companies: two companies in Gwangyang Hinterland and five companies in Busan Hinterland, though Masan FTZ was only ranked on the 24th, on the rank of world FTZ. This paper aims at finding the cargo volume necessary for achieving the maximum efficiency. This research proposes an appropriate strategy to keep a certain amount of cargo volume stable and presents the Port Hinterland differentiation strategies of Gwangyang and Busan.

• Korean Journal of Clinical Laboratory Science
• /
• v.47 no.3
• /
• pp.105-111
• /
• 2015

In late December 2013, the Ebola virus emerged from West Africa. The outbreak started in Guinea and rapidly spread to Liberia and Sierra Leone. Initially, the virus is spread to the human population after contact with infected wildlife and then spread person-to-person through direct contact with body fluids such as blood, sweat, urine, semen, and breast milk. The Ebola virus infects endothelial cells, mononuclear phagocytes and hepatocytes. It causes massive damage to internal tissues and organs, such as blood vessels and the liver, and ultimately death. Most tests for the virus RNA rely on a technology called reverse-transcriptase polymerase chain reaction (RT-PCR). While this method is highly sensitive, it is also expensive, requiring skilled scientists, and delicate power supplies. The strip analytical technique (enzyme-linked immunosorbent assay or ELISA) detects antigens or antibodies to the Ebola virus. This test is cheap and does not require electricity or refrigeration. Despite ongoing efforts directed at experimental treatments and vaccine development, current medical work on the Ebola viral disease is largely limited to supportive therapy. Thus, rapid and reliable diagnoses of the Ebola virus are critically important for patient management, infections, prevention, and control measures.

• Journal of Technology Innovation
• /
• v.28 no.4
• /
• pp.97-126
• /
• 2020

This study evaluated its potentials by quantitatively analyzing the national economic impact of the smart home-related industry, which is attracting attention as a core industry of the 4th industrial revolution. For the analysis, the smart home-related industries were classified into manufacturing and service industries through a literature review of the previous studies. Using the 2018 input-output table, this paper analyzed linkage effects between industries as well as spillover effects in the production, value-added, employment and job. As a result, the smart home manufacturing and service sectors showed a higher spillover effect in value-added than other industries in each industrial field. In the smart home industry, the spillover effects of manufacturing sector to service sector are larger than those of service sector to manufacturing sector. Moreover, it was confirmed that smart home industry was highly related to not only the technology-intensive industry, but also the service sector for smart cities, smart cars, Fin-tech, and etc. On the other hand, the smart home manufacturing sector is a final demanding industry with relatively higher backward linkage effect than forward linkage effect. In the smart home service sector, the forward linkage effect was relatively high compared with the backward linkage effect, indicating that it was an industry with a high supply function to other industries.

• International Area Studies Review
• /
• v.15 no.2
• /
• pp.125-150
• /
• 2011

As the economy grows, there is a concern that the economic development causes a productivity reduction because of the service intensive growth. However, the economy of developed countries encounter with the productivity growth as their economy grows, which phenomenon called Baumol's paradox. Oulton (1999, 2001) find out the reason of Baumol's paradox in a forward and backward chain effects. So, this paper is aimed at verifying the theory of Oulton (1999, 2001). Moreover, we test the difference effect between a consumer service and producer service input using a dummy variable. We use the Input-Output Table (1990, 1995, 2000, 2005) that is offered by the Bank of Korea to accomplish the purpose of our research that is represented above. We find out that the Korea's intermediate producer service inputs cause a multifactor productivity growth. That result is matched with the Oulton (1999, 2001)'s theory. But, the intermediate consumer service inputs don't have a significant effect on a multifactor productivity. The result of verifying the effect of intermediate producer service inputs among industries shows that the effects on manufacture industries are less than other industries.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.34 no.2
• /
• pp.103-108
• /
• 2001

Toxic effect of TBTO on larva flounder was studied by the use of a food-chain system in which indirect toxicity from seawater or/and plankton can be measured, Under the treatment of 0.5 ng/L TBTO, the combined effect of diets ( Chlorella and rotifer) and seawater was significant by synergism, although the sole effect from TBTO treated diets or seawater was equally not, The values of $LT_{50}$ from results of acute-toxicity experiments for juvenile flounder were estimated to be 230.0, 48.0, 24.0, 14.6, 9.3 5.5 3.0 and 1.7 hr at 1, 10, 25, 50, 100, 250, 500 and 1000 ng/L of TBTO, respectively, and $96hr-LC_{50}$ was 3.5 ng/L. From the above results, the experiments for chronic toxicity of TBTO was executed at the concentration range of $1\sim10 ng/L$. In long-term experiments for four months, the weight and the total length of the juvenile flounder in all TBTO treated experiments slowly increased when compared to control. No significant differences in the growth and survival of the juvenile flounder were found in the treatment of 1 ng/L TBTO(P>0.05), But, $90\%$ of the juvenile flounder died in 20 days under TBTO treated seawater at both concentrations of 5 and 10 ng/L, The TBTO treated on seawater was more effective and significantly different in the growth and survival of the juvenile flounder when compare with that on artificial diets (P<0.05). From the all results, TBTO should be regulated below 5 ng/L in a coast.