• Korean Journal of Microbiology
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• v.50 no.2
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• pp.87-94
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• 2014

Nitric oxide (NO), which has been recognized as an integral molecule in maintaining homeostasis, plays an important role in host defense against microbes. NO has diverse antimicrobial mechanisms by directly and/or indirectly interacting with microbes. Under the circumstance that there is an urgent need for a new class of antimicrobial agents due to antibiotic resistance, much effort has been made to develop a NO-based antimicrobial agent. In order to make it possible, strategies to store and release NO in a controlled manner are required because NO has a gaseous property and a very short half-life. In this review, we described NO biochemistry and its mechanisms of antimicrobial activity. In additions, we introduced various NO-releasing systems that improve NO's antimicrobial activity.

• KIEAE Journal
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• v.17 no.2
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• pp.35-43
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• 2017

Purpose: The purpose of this study is to find out the characteristics of service (landfill) costs (hereinafter, the "landfill costs") applied to the dissolution promotion committee and analyze the characteristics of landfill costs at the time where the dissolution of promotion body is increasing with the authority of the head of local government regarding the territory difficult with the continuous promotion by delaying or suspending the project for a prolonged period or suspending the project through the dissolution of the project body by the promotion committee and cooperative union since the flawless promotion of the maintenance project. Method: After revising the law in February 2012, the survey and analysis is made for the status of applying landfill costs and maintenance project scale of the dissolution promotion committee not confirmed in details around a total of 20 regions, including, 9 regions of redevelopment projects completed with the advance review, 7 regions of re-construction projects and 4 regions of urban environment maintenance projects from the total of 59 regions, Result: The influence on the landfill costs is shown to be greatest in the service expenses and management and supervision on this field has significance for the maintenance project perceived as private project, rather than public project, that the public management is neglected with insufficient presentation of operation criteria and so forth that it displays the tendency to lead to the discrete operation of the project body. In order to enhance the transparency of operating costs for the projects that are led by private capital, it is required to strengthen the role of public sector through enthusiastic intervention by the public sector in standardization of operation criteria, presentation of guideline and so forth.

• Journal of Korean Tunnelling and Underground Space Association
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• v.9 no.1
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• pp.83-89
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• 2007

As tunnel excavation generats stress release, a stability security of tunnel face is mainly important in case of tunnel excavation in the weak grounds. Using the steel bar or glass fiber pipe which had regular hardness, a face bolt method to reinforce previously is applied to an excavation object tunnel face aspect among measures methods regarding this. Therefore, used $FLAC^{3D}$ Ver. 2.1 on 5 Case of 0.5D (2EA), 1.0D, 1.5D, 2.0D with the length and 6 Case of 0, 20, 40, 60, 80, 100EA with the number of the bolt that a face bolt method was installed at these papers in the necessary weak grounds in order to review applicability of the tunnel face reinforcement method that used these face bolts, and executed three dimension continuous analysis.

• Environmental Analysis Health and Toxicology
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• v.23 no.4
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• pp.257-265
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• 2008

Nanotechnology is emerging as one of the key technologies of the 21 st century and is expected to enable one to broaden the applicability across a wide range of sectors that can benefit public and improve industrial competitiveness. Already, consumer products containing nanomaterials are available in markets including coatings, computers, clothing, cosmetics, sports equipment and medical devices. Recently, Institute of Occupational Medicine in UK reported an occupational hygiene review for nanoparticles in the viewpoint of nanotoxicity. They reported that the exposure control is very important issues in workplace for exposure assessment, but no proper methods are available to measure the extent of exposures to nanoparticles in the workplace. Therefore, for the estimation of exposure of nanomaterials, we have to approach the material-balance methodology, which similarly carried out in TRI (toxic release inventory) for hazardous chemicals. In order to use this methodology, the exposure source of nanomaterials should be determined firstly. Therefore, herein we investigated the main sources and processes for the exposure to nanomaterals by conducting the survey. The results could be used to define and assess nanohazard sources.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.51-62
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• 2022

Numerous insect pests threaten the Korean orchard industry through feeding on various tissues of fruit trees. Generally, the control of economically important orchard pests is based on the use of chemical insecticides. Owing to growing concerns regarding the environmental and human health effects of insecticides, environment-friendly pest control strategies are urgently needed. Pheromones of orchard pests could lead to an environmentally safe control system based on mating disruption or mass trapping. This review summarizes the functions and compounds of known pheromones from 51 orchard pests in Korea. The pheromones identified to date from 14 species in the families Miridae, Aphididae, Diaspididae, Pseudococcidae, Rutelidae, Cecidomyiidae, and Eurytomidae and 26 species in the order Lepidoptera are female-produced sex pheromones that attract only males. In contrast, all known examples for 11 species in the families Alydidae, Pentatomidae, Thripidae and Cerambycidae are male-produced aggregation pheromones that attract both sexes. Research on pheromones in new pests, kairomones in key orchard pests, mating disruption dispensers to generate prolonged release of the pheromones, and trap design and trap location for mass trapping will be required for the expanded use of pheromones and other semiochemicals in orchard pest management in the future.

• Macromolecular Research
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• v.13 no.3
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• pp.167-175
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• 2005

This review explores recent works involving the use of the self-assembled nanoparticles of bile acid-modified glycol chitosans (BGCs) as a new drug carrier for cancer therapy. BGC nanoparticles were produced by chemically grafting different bile acids through the use of l-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC). The precise control of the size, structure, and hydrophobicity of the various BGC nanoparticles could be achieved by grafting different amounts of bile acids. The BGC nanoparticles so produced formed nanoparticles ranging in size from 210 to 850 nm in phosphate-buffered saline (PBS, pH=7.4), which exhibited substantially lower critical aggregation concentrations (0.038-0.260 mg/mL) than those of other low-molecular-weight surfactants, indicating that they possess high thermodynamic stability. The SOC nanoparticles could encapsulate small molecular peptides and hydrophobic anticancer drugs with a high loading efficiency and release them in a sustained manner. This review also highlights the biodistribution of the BGC nanoparticles, in order to demonstrate their accumulation in the tumor tissue, by utilizing the enhanced permeability and retention (EPR) effect. The different approaches used to optimize the delivery of drugs to treat cancer are also described in the last section.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.8
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• pp.588-595
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• 2014

Carbon nanomaterials such as fullerene, carbon nanotube and graphene are representative nanomaterials and widely used in various fields. Carbon nanomaterials can be exposed to environments during their production, usage and disposal, spreading to different systems and posing a great threat to various ecological receptors. Researches are conducted in order to determine the possibility of groundwater exposure to carbon nanomaterials due to their release and passage through soils. If soils can play a significant role in limiting the transport of carbon nanomaterials, the possibility of groundwater exposure to carbon nanomaterials can be reduced greatly. This review paper presented the research works performed for the mobility of carbon nanomaterials in soil media. Also, the paper provided the factors affecting the transport of carbon nanomaterials in soil media along with the DLVO theory/colloid filtration theory/transport model, which are used to describe the transport of carbon nanomaterials in soil media. Recently, production of carbon nanomaterials and their commercial and environmental applications increase rapidly in Korea. Therefore, researches regarding the fate and transport of domestic carbon nanomaterials in soil environments should be performed in various environmental conditions.

• The Journal of the Korea Contents Association
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• v.16 no.9
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• pp.726-738
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• 2016

This study selected the Marine Corps camp accident in 2013 as its subject and analyzed it in order to explore the relevance of media framing on discourse on the safety of outdoor experience activities. Data were collected from search sites provided by news coverage data from March 26, 2010 when the sinking of the South Korean Navy corvette Cheonan occurred in South Korea, which had seen a surge in Marine Corps experience camps, to July 21, 2013, a few days after the Marine Corps camp accident. Data about a total of 211 cases 138 cases before the Marine Corps camp accident, and 73 cases after the accident were inductively analyzed. According to the results, news coverages on the Marine Corps camp were largely divided into positive framing that glamorized outdoor experience activities before the accident and negative framing after the accident. To put it concretely, the framing before the accident tended to glamorize outdoor experience activity as the best educational program which helped the participants to enhance their patience and sense of independence through boot camp experience, thereby increasing their self-esteem and arousing their cooperative spirit as members of society. However, after the accident media framing tended to publicize insensitivity to safety. The media framing characterized by dualistic coverage is considered to be an obstacle to the spread of safety culture, which is required in South Korean society. Therefore, media need to maintain more cool-headed and objective attitudes when reporting news.

• Fire Science and Engineering
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• v.33 no.5
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• pp.94-102
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• 2019

As the importance of first responses for fire accidents has grown in the safety management of nuclear power plants, a systematic approach to measure firefighters' psychological states and competence is needed. The current study investigated the construct of the risk perception of the firefighters working near nuclear power plant sites, and then developed and validated a new scale to measure firefighters' risk perception regarding nuclear power plant accidents. The scale items were developed on the basis of literature review and interviews with the firefighters working near nuclear power plant sites. In order to validate the new scale, we recruited 180 firefighters from five fire stations in the vicinity of the nuclear power plants in Jeonnam Province, Gyeongbuk Province, and Busan. The results of exploratory factor analyses revealed that the scale consisted of five factors: "manual" reflecting a lack of response guidelines and manuals for fire incidents and radioactive material release; "fear" reflecting a fear of fire incidents in the nuclear power plants and their catastrophic consequences; "resource" reflecting a lack of protective equipment and manpower for responding to fire incidents in the nuclear power plants; "trust" reflecting trust and cooperation with the counterpart institutions for firefighting in the nuclear power plants; and "knowledge" reflecting the knowledge of radioactivity and firefighting in the nuclear power plants. Further analyses provided statistical evidence supporting for the 15-item scale's internal consistency and construct validity. Finally, We discussed the implication and limitations of the current research.

• Nuclear Engineering and Technology
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• v.39 no.5
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• pp.603-616
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• 2007

Roy Huddle, having invented the coated particle in Harwell 1957, stated in the early 1970s that we know now everything about particles and coatings and should be going over to deal with other problems. This was on the occasion of the Dragon fuel performance information meeting London 1973: How wrong a genius be! It took until 1978 that really good particles were made in Germany, then during the Japanese HTTR production in the 1990s and finally the Chinese 2000-2001 campaign for HTR-10. Here, we present a review of history and present status. Today, good fuel is measured by different standards from the seventies: where $9*10^{-4}$ initial free heavy metal fraction was typical for early AVR carbide fuel and $3*10^{-4}$ initial free heavy metal fraction was acceptable for oxide fuel in THTR, we insist on values more than an order of magnitude below this value today. Half a percent of particle failure at the end-of-irradiation, another ancient standard, is not even acceptable today, even for the most severe accidents. While legislation and licensing has not changed, one of the reasons we insist on these improvements is the preference for passive systems rather than active controls of earlier times. After renewed HTGR interest, we are reporting about the start of new or reactivated coated particle work in several parts of the world, considering the aspects of designs/ traditional and new materials, manufacturing technologies/ quality control quality assurance, irradiation and accident performance, modeling and performance predictions, and fuel cycle aspects and spent fuel treatment. In very general terms, the coated particle should be strong, reliable, retentive, and affordable. These properties have to be quantified and will be eventually optimized for a specific application system. Results obtained so far indicate that the same particle can be used for steam cycle applications with $700-750^{\circ}C$ helium coolant gas exit, for gas turbine applications at $850-900^{\circ}C$ and for process heat/hydrogen generation applications with $950^{\circ}C$ outlet temperatures. There is a clear set of standards for modem high quality fuel in terms of low levels of heavy metal contamination, manufacture-induced particle defects during fuel body and fuel element making, irradiation/accident induced particle failures and limits on fission product release from intact particles. While gas-cooled reactor design is still open-ended with blocks for the prismatic and spherical fuel elements for the pebble-bed design, there is near worldwide agreement on high quality fuel: a $500{\mu}m$ diameter $UO_2$ kernel of 10% enrichment is surrounded by a $100{\mu}m$ thick sacrificial buffer layer to be followed by a dense inner pyrocarbon layer, a high quality silicon carbide layer of $35{\mu}m$ thickness and theoretical density and another outer pyrocarbon layer. Good performance has been demonstrated both under operational and under accident conditions, i.e. to 10% FIMA and maximum $1600^{\circ}C$ afterwards. And it is the wide-ranging demonstration experience that makes this particle superior. Recommendations are made for further work: 1. Generation of data for presently manufactured materials, e.g. SiC strength and strength distribution, PyC creep and shrinkage and many more material data sets. 2. Renewed start of irradiation and accident testing of modem coated particle fuel. 3. Analysis of existing and newly created data with a view to demonstrate satisfactory performance at burnups beyond 10% FIMA and complete fission product retention even in accidents that go beyond $1600^{\circ}C$ for a short period of time. This work should proceed at both national and international level.