• Journal of Microbiology
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• v.41 no.4
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• pp.340-344
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• 2003

The group I intron from Tetrahymena thermophila has been demonstrated to employ splicing reactions with its substrate RNA in the trans configuration. Moreover, we have recently shown that the transsplicing group I ribozyme can replace HCV-specific transcripts with a new RNA that exerts anti-viral activity. In this study, we explored the potential use of RNA replacement for cancer treatment by developing trans-splicing group I ribozymes, which could replace tumor-associated RNAs with the RNA sequence attached to the 3' end of the ribozymes. Thymidine phosphorylase (TP) RNA was chosen as a target RNA because it is known as a valid cancer prognostic factor. By performing an RNA mapping strategy that is based on a trans-splicing ribozyme library, we first determined which regions of the TP RNA are accessible to ribozymes, and found that the leader sequences upstream of the AUG start codon appeared to be particularly accessible. Next, we assessed the ribozyme activities by comparing trans-splicing activities of several ribozymes that targeted different regions of the TP RNA. This assessment was performed to verify if the target site predicted to be accessible is truly the most accessible. The ribozyme that could target the most accessible site, identified by mapping studies, was the most active with high fidelity in vitro. Moreover, the specific trans-splicing ribozyme reacted with and altered the TP transcripts by transferring an intended 3' exon tag sequence onto the targeted TP RNA in mammalian cells with high fidelity. These results suggest that the Tetrahymena ribozyme can be utilized to replace TP RNAs in tumors with a new RNA harboring anti-cancer activity, which would revert the malignant phenotype.

• Journal of the Optical Society of Korea
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• v.19 no.3
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• pp.228-236
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• 2015

Fluorescence recovery after photobleaching (FRAP) is a well-established method commonly used to measure the diffusion of fluorescent solutes and biomolecules in living cells or tissues. Here a fiber-optic-based FRAP (f-FRAP) system was developed, and validated using macromolecules in water and agarose gels of different concentrations. We applied f-FRAP to measure the site-specific diffusion of fluorescein (NaFluo) in peritoneal membranes (PMs) on the liver, cecum, and kidney of a living rat during peritoneal dialysis. Diffusion of fluorescein in PM varied in a time-dependent manner according to the type of organ ($D_{PM\;on\;Liver}/D_{NaFluo}=0.199{\pm}0.085$, $D_{PM\;on\;Cecum}/D_{NaFluo}=0.292{\pm}0.151$, $D_{PM\;on\;Kidney}/D_{NaFluo}=0.218{\pm}0.110$). The proposed method allows direct quantitative measurement of the three-dimensional diffusion in local PM in vivo, which was previously inaccessible by peritoneal function test methods such as peritoneal equilibration test (PET) and standardized PM assessment (SPA). f-FRAP is promising for local and dynamic assessments of peritoneal pathophysiology and the mass transport properties of PMs, presumed to be affected by variation of tissue structures over different organs and functional changes of the PM with years of peritoneal dialysis.

• Journal of the Korean Institute of Gas
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• v.20 no.6
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• pp.1-8
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• 2016

Gu-mi hydrogen fluoride leak accident in 2012 was amplified social anxiety for chemical accidents. To relieve these anxieties Off-site Risk Assessment was introduced in 2015. Off-site Risk Assessment is targeted at most chemicals, and most of the high-pressure-toxic gases which are mainly used in high-tech industries such as semi conductor, display, Photovoltaic panels industry are included in the substance of the Off-site Risk Assessment. Since Korean companies occupy a high market share in high-tech industries, high pressure-toxic domestic gas consumption is constantly increasing. Accordingly, it is expected to increase the possibility of accidents. In accordance with the circumstances, this study was to conducted Consequence Analysis(CA) about high pressure-toxic gases those are high demand in domestic. CA was used for ALOHA developed by US EPA & US NOAA and the CA result of Arsine was the largest at 4,700 m. CA results are expected to be utilized for determining the effective Safety distances when high pressure-toxic gas leak.

• Architectural research
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• v.16 no.3
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• pp.81-92
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• 2014

This study discusses the features of the lighting and ventilation regulations for residential buildings in Hong Kong. Given the compact built environment and public concerns about the environmental quality of housing, various lighting and ventilation regulations have been enacted in Hong Kong. The application of building regulations on the micro scale and incentive systems on the macro scale are present, and the governments' calls for more active participation of the private sector and use of the building environmental assessment tools were also noted. Unlike South Korea, however, Hong Kong was found to adopt more performance-based standards, consider the external factors of the lighting and ventilation conditions together with the indoor elements, and provide specific design guidelines. Notwithstanding the different climatic conditions and socio-political contexts of Hong Kong and South Korea, these findings provide some policy implications for the South Korean government in its efforts to achieve a healthy environment for high-rise, high-density housing. It is suggested that the South Korean government adopt more on-site measurement methods to reflect the environmental conditions accurately and broaden the scope and scale of the implementation of the lighting and ventilation regulations with more specific, practical planning and design guidelines.

• International Journal of Internet, Broadcasting and Communication
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• v.16 no.2
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• pp.255-266
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• 2024

The purpose is to evaluate evacuation safety by simulating the toxic effects of hydrogen fluoride leaks in areas surrounding national industrial complexes and to suggest alternatives for areas that do not satisfy evacuation safety. For human casualties caused by hydrogen fluoride leakage accidents, Available Safe Egress Time (ASET) is calculated by the toxic effects quantified with the Areal Locations of Hazardous Atmospheres (ALOHA), an off-site consequence assessment program. The Required Safe Egress Time (RSET) is calculated through Pathfinder, an evacuation simulation program. Evacuation safety is assessed by comparing ASET and RSET. The ALOHA program was used to evaluate the time to reach AEGL-2 concentration in 12 scenarios. The Pathfinder program was used to assess the total evacuation time of the high school among specific fire-fighting objects. Of the 12 accident scenarios, ASET was larger than RSET in the worst-case scenarios 1 and 9. For the remaining 10 accident scenarios, the ASET is smaller than the RSET, so we found that evacuation safety is not guaranteed, and countermeasures are required. Since evacuation safety is not satisfactory, we proposed to set up an evacuation area equipped with positive pressure equipment and air respirators inside specific fire-fighting objects such as the high school.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.10 no.3
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• pp.133-141
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• 2012

The impacts influenced on the performance and safety of a repository are classified as units of Features, Events, and Processes (FEP), for the total system performance assessment (TSPA) related to the permanent disposal of HLW. The importance is evaluated in consideration of the frequency, consequence, regulation, suitability of a specific site, etc. and then these are grouped as a similar FEP. A scenario describing the migration of radionuclide from the repository to the biosphere is derived from understanding the interaction among these groups. KAERI has developed the KAERI FEP lists by review and collation of the foreign studies. The KAERI FEP list has been reviewed by several Korean experts. The five major scenarios describing possible future evolutions of the geological disposal system have been developed by RES and PID methods. Also the CYPRUS which is a KAERI integrated database management system for the total system performance assessment (TSPA) related to the permanent disposal of HLW has been developed and the results of the FEP and scenario development have been uploaded in this system.

• Journal of the Korean Society of Safety
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• v.38 no.3
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• pp.102-109
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• 2023

Following the accident at Fukushima, the true impact of multi-unit accidents came to light. Accordingly, research related to multi-unit accident effect analysis, risk evaluation, and accident prevention/prevention technology has been conducted. Specific examples are mobile/fixed equipment such as multi-barrier accident coping strategy (MACST) and diverse and flexible coping strategies (FLEX), which have been introduced and installed in multi-units for preventing and mitigating multi-unit accidents. These strategies are useful for enhancing the safety of nuclear power plants (NPPs); however, a more efficient strategy is required in terms of the costs of physical and human resources. To effectively and efficiently mitigate an increase in multi-unit accidents, it is necessary to not only to utilize mobile/fixed equipment but to also use crosstie options with resources that already exist at NPPs. Therefore, we analyzed the current international and domestic status of crosstie systems technology and propose a method to evaluate feasibility alongside risk based on a multi-unit probabilistic safety assessment (PSA). To analyze the international and domestic status of crosstie systems technology, actual cases and related research were studied, and a list of potential crosstie safety resources was derived. Additionally, a case study was performed on crosstie cases of two systems within the assumed six units on-site under a multi-unit accident, and a multi-unit PSA-based risk evaluation method is proposed.

• Journal of Environmental Impact Assessment
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• v.10 no.2
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• pp.123-133
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• 2001

Gaussian dispersion model is the most widely used tool for the ground level air pollution simulation. Though in spite of the convenience there are important problems on the Pasquill- Gifford' stability classification scheme which was used to define the turbulent state of the atmosphere or to describe the dispersion capabilities of the atmosphere which was each covers a broad range of stability conditions, and that they were very site specific, and the vertical dispersion calculation formula on the case of the unstable atmospheric condition. This paper was carried out to revise the Gaussian dispension model for the purposed of increase the modeling performance and propose the revised model, which was composed of the turbulent characteristics in the unstable atmospheric conditions. The proposed models in this study were composed of the profile method, Monin-Obukhove length, the probability density function model and the lateral dispersion function which was composed of the turbulent parameters, $u_*$(friction velocity), $w_*$(convective velocity scale), $T_L$(lagrangian time scale) for the model specific. There were very good performance results compare with the tracer experiment result on the case of the short distance (<1415m) from the source, but increase the simulation error(%) to stand off the source in the all models. In conclusion, the revised Gaussian dispersion model using the turbulent characteristics may be a good contribution for the development of the air pollution simulation model.

• Ocean Systems Engineering
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• v.8 no.3
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• pp.281-312
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• 2018

Characteristics of a turbulence wind model control the magnitude and frequency distribution of wind loading on floating offshore wind turbines (FOWTs), and an in-depth understanding of how wind spectral characteristics affect the responses, and ultimately the design cost of system components, is in shortage in the offshore wind industry. Wind spectrum models as well as turbulence intensity curves recommended by the International Electrotechnical Commission (IEC) have characteristics derived from land-based sites, and have been widely adopted in offshore wind projects (in the absence of site-specific offshore data) without sufficient assessment of design implications. In this paper, effects of wind spectra and turbulence intensities on the strength or extreme responses of a 5 MW floating offshore wind turbine are investigated. The impact of different wind spectral parameters on the extreme blade loads, nacelle accelerations, towertop motions, towerbase loads, platform motions and accelerations, and mooring line tensions are presented and discussed. Results highlight the need to consider the appropriateness of a wind spectral model implemented in the strength design of FOWT structures.

• Economic and Environmental Geology
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• v.32 no.2
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• pp.151-159
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• 1999

This research was carried out to evaluate the possible usage of natural clay materials collected from the Kimpo landfill site and nearby clay mines as a clay liner material. In order to evaluate the possible usage as a clay liner material, specific gravity, pH, loss-on-ignition, organic carbon content and mineralogical composition of clay materials were measured. The Atterberg limit test and the size analysis were performed for the engineering classification and the prediction of hydraulic conductivity of clay materials. Caution exchange capacity and batch tests were also carried out for the assessment of attenuation capacity. Clay specimens of KPNCL, KP-1, KP-2 and SH were recommended as suitable clay linder materials from viewpoint of their basic quality and attenuation capacity.