• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.2 s.29
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• pp.103-110
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• 2007

This study estirmted the appropriate pollutant load reduction from point sources in Jinhae Bay, Korea, using an eco system model. The results of COD values in the inner part of the bay obtained through the simulation by ecosystem model were greater than 3.0mg/L, and exceeded the limits of Korean Coastal Water Quality Grade III. Engineering countermeasures to reduce the $70\sim90%$ of all land based pollution load or organic and inorganic material loads from point sources by more than 50% were required to keep the COD levels below 2 mg/L. The reduction loads is 5,632kg/day of COD, 481kg/day of DIP and 7,991 kg/day of DIN in case of the reduction of both the organic and nutrients. The estimated environmental currying capacity of that case is 13,112kg/day of COD, 206kg/day of DIP and 3,425kg/day of DIN to keep the COD levels below 2mg/L.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.2
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• pp.85-93
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• 2012

We study on the distribution characteristics of antifouling agents such as Sea-nine 211, Irgarol 1051, Diuron using HS-SPME method in southwestern coast of Korea. Short half-life of Sea-nine 211 was distributed in very low concentrations and/or below detection limits in all of the sampling points, both water and sediments samples. Irgarol 1051 was detected to have the highest concentration respectively $6.98{\mu}g/L$, 28.50 ng/g-dry wt in the seawater and sediments, and regional distribution characteristics did not appeared. Strong bioaccumulation and long half-life of Diuron was distributed higher concentration than in all sampling point and was analyzed to have the highest concentration(3882.22 ng/g-dry wt) Mo7(Mokpo)'s sediment. Irgarol 1051 and Diuron distributed in the shipbuilding industry and ship marina are located just at the point to found in high concentrations. In addition, the distribution of the antifouling agent materials were lower in concentration than in inner bay to outter bay in sediments. Antifouling agent materials from these results were contaminated high potential from port and shipbuilding industry located in inner bay.

• Journal of the Korean Society for Railway
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• v.14 no.5
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• pp.433-441
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• 2011

It is a fact that the straightening of track alignment is one of the undoubted ways to improve the train speed on conventional lines, while that requires huge investment resources. Therefore, the operation of a tilting train as well as the minimum improvement of track is suggested as an effective and economical alternative way for the speed-up of conventional lines. Since a driving mechanism of tilting train is different from those of existing trains, in order to make sure its operation safety and stability on conventional line, the performance of track and roadbed must be preferentially evaluated on the conventional line. Furthermore, it is necessary to estimate the tilting-train-induced roadbed response in detail since the roadbed settlement can lead to the track deformation and even derailment. In this research, the patterns of wheel load and lateral force were monitored and analyzed through the field tests, and the derailment coefficient and degree of wheel off-loading were calculated in order to evaluate the tilting train running safety depending on the running speeds (120km~180km) on the conventional line. Moreover, roadbed pressure, settlement and acceleration were also observed as tilting-train-induced roadbed responses in order to estimate the roadbed stability depending on the running speeds. Consequently, the measured derailment coefficient and degree of wheel off-loading were satisfied with their own required limits, and all of the roadbed responses were less than those of existing high-speed train (KTX) over an entire running speed range considered in this study. As a result of this study, the tilting train which will be operated in combination with existing trains is expected to give no adverse impact on the conventional line even with its improved running speed.

• Journal of the Korean Chemical Society
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• v.46 no.4
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• pp.317-323
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• 2002

The composition of trace materials in domestic circulated LPG are determined. The sampling points are two cylinders of LPG cylinder re-inspection center, six vaporizer of LPG-supplying group facilities, and the compressed oil from one LPG station. In the trace materials from cylinder of LPG cylinder-reinspection center, alkene and diene derivative (No. of carbon ${\leq}9),$ aromatic compounds, and tarry chemicals(No. of carbon ${\geq}10)$ are 1.5~39.9%, 0.7%, 57.8~96.0%, respectively. While in the trace materials from LPG-supplying group facilities and in the oil from LPG station, tarry chemicals(No. of carbon>10) exceed 96.6%. Nine samples are classified into three clusters. One cluster is the sample of SE company cylinder-reinspection center(Euclidian distance between S company LPG cylinder-reinspection center and SE company cylinder-reinspection center=2.11), the other is the sample of SE company LPG cylinder-reinspection center(Euclidian distance between from samples of LPG-supplying group facilities including compressed oil from LPG station=0.110) the third is the samples of LPG-supplying group facilities(Euclidian distances among them<0.075). The compositions of samples from LPG-supplying group facilities are similar to those of oil from LPG station. Furthermore densities of samples from LPG-supplying group facilities and compressed oil in LPG station are 0.873, 0.873 [0.00798 (99% confidence limits) respectively. It was presumed that tarry chemicals had been leached from the compressed oil of LPG supplying facilities.

• The Korean Journal of Pesticide Science
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• v.3 no.2
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• pp.37-46
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• 1999

In order to ascertain the safety of the systemic insecticide carbofuran-treated crops, samples of garlic, peanut and potato were collected randomly from markets located in the main producing areas and analyzed for the residue of carbofuran and its main metabolite, 3-hydroxycarbofuran. The in vitro metabolism of carbofuran in phosphate buffer extracts of the crops was investigated. Two (M-12 and M-16) out of 20 mature garlic samples contained 0.13 and 0.07 mg/kg of carbohran, respectively, showing a detection incidence of 10%. The residue levels were less than the maximum residue limit (0.5 ppm) set by Korean Food and Drug Administration. Only one sample of mature garlic (M-12) out of 20 contained 0.13 mg/kg of 3-hydroxycarbofuran. The residues of carbofuran and 3-hydroxycarbofuran in the immature garlic, peanut and potato samples were less than the detection limits, 0.02 mg/kg for carbofuran and 0.06 mg/kg for 3-hydroxycarbofuran. The application of carbofuran to the fields of garlic, peanut and potato would be safe, considering that the estimated maximum acceptable daily intake of carbofuran from garlic was 0.0013 mg which is 0.24% of the maximum acceptable daily intake (0.55 mg). Carbofuran was hydrolyzed in vitro mainly to carbofuran phenol (m/z 164) in the respective phosphate buffer extracts of the three crops in contrast to the major oxidative metabolism in situ. The amount of the metabolite increased with the incubation time.

• Journal of Radiation Protection and Research
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• v.42 no.1
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• pp.33-41
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• 2017

Background: Phosphate rock and its by-product are widely used in various industries to produce phosphoric acid, gypsum, gypsum board, and fertilizer. Owing to its high level of natural radioactive nuclides (e.g., $^{238}U$ and $^{226}Ra$), the radiological safety of workers who work with phosphate rock should be systematically managed. In this study, $^{238}U$, $^{232}Th$, $^{226}Ra$, and $^{40}K$ levels were measured to analyze the transport characteristics of these radionuclides in the production cycle of phosphate rock. Materials and Methods: Energy dispersive X-ray fluorescence and gamma spectrometry were used to determine the activity of $^{238}U$, $^{232}Th$, $^{226}Ra$, and $^{40}K$. To evaluate the extent of secular disequilibrium, the analytical results were compared using statistical methods. Finally, the distribution of radioactivity across different stages of the phosphate rock production cycle was evaluated. Results and Discussion: The concentration ratios of $^{226}Ra$ and $^{238}U$ in phosphate rock were close to 1.0, while those found in gypsum and fertilizer were extremely different, reflecting disequilibrium after the chemical reaction process. The nuclide with the highest activity level in the production cycle of phosphate rock was $^{40}K$, and the median $^{40}K$ activity was $8.972Bq{\cdot}g^{-1}$ and $1.496Bq{\cdot}g^{-1}$, respectively. For the $^{238}U$ series, the activity of $^{238}U$ and $^{226}Ra$ was greatest in phosphate rock, and the distribution of activity values clearly showed the transport characteristics of the radionuclides, both for the byproducts of the decay sequences and for their final products. Conclusion: Although the activity of $^{40}K$ in k-related fertilizer was relatively high, it made a relatively low contribution to the total radiological effect. However, the activity levels of $^{226}Ra$ and $^{238}U$ in phosphate rock were found to be relatively high, near the upper end of the acceptable limits. Therefore, it is necessary to systematically manage the radiological safety of workers engaged in phosphate rock processing.

• Journal of the Korea Concrete Institute
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• v.17 no.4 s.88
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• pp.587-594
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• 2005

The purpose of seismic design is to ensure the serviceability of buildings against earthquake, which might be occurred during the service life of buildings, and to minimize the loss of life by preventing their failure under strong earthquake. The lack resistance of walls resulting from a tendency toward high-rise apartment buildings with shear walls and use of piloti would lead to a concentration of inelastic behaviors in their weak story. In this study, the seismic performance of reinforced concrete shear wall buildings haying piloti was analyzed by using the evaluation techniques which was proposed by FEMA 273 and ATC-40. The results from comparison with these two techniques are summarized as follows.; The results of elastic analysis method for seismic performance evaluation show that the effect of piloti and building height decrease performance index. In case of shear wall building, the state of insufficient shear stress governs their overall performance and it becomes evident in the case of the buildings with more than 25 stories. For the buildings of piloti, the change of mass, weak story, as well as insufficient shear stress, decrease the performance index rapidly compared with the performance index of the buildings without piloti. The results, obtained from the nonlinear static analysis using capacity spectrum method, indicate that the performance Point increases for the structure having Piloti and high story. Also, deformation limits of buildings satisfy the allowable criteria at the life safety level, but the immediate occupancy level is exceeded in buildings which have more than 25 stories.

• Journal of Korea Technology Innovation Society
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• v.18 no.4
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• pp.667-692
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• 2015

The study examined the Korean medicine industry from the perspective of the innovation system theory of each business, while it concentrated on the conflict between traditional Korean medicine and Western medicine, which have a major influence on the innovation system of Korean medicine industry, rather than the innovation system itself. The Korean healthcare system is a dual system of Western and Korean medicine, yet the definitions of Western medical practices and Korean medical practices are ambiguous. Thus the distinction of dual system depends on judicial precedents, and the innovation of Korean medicine has been inhibited due to the excessive emphasis placed on the Western medical practice in both healthcare system and pharmaceutical system. First of all, the usage of most medical devices derived from the development of modern medical engineering is not permitted in the Korean medicine industry, on the basis that most of the medical devices were originated from the Western medicine field. Secondly, new drugs using natural substances, once approved by the drug administration, cannot be prescribed by the Korean medicine industry although they are developed based on Korean medicine. Thirdly, the major safety issues on herbal medicine are about hazardous materials in medicinal herbs and liver toxicity of prescribed herbal medicine. The problem of hazardous materials can be solved by appropriate quality and safety tests in the cultivation and importation process. Whereas the Korean medicine circles points out that the liver toxicity issue is only a unilateral condemnation by the Western medicine circles.

• Journal of the Korean Institute of Gas
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• v.24 no.4
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• pp.84-92
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• 2020

Most facilities in chemical plants operate in environments that are outside the range of temperature and pressure that can be encountered on a daily basis, and are vulnerable to aging due to these stresses and environmental conditions. The facilities exposed to these conditions are not only likely to fail due to cumulative damage, but also lead to accidents if maintenance and replacement are not performed.Recommendation guidelines called risk-based inspection are widely used around the world-wide. However, limits exist for facilities that have already elapsed for a certain. As a result of the survey on the aging of Ulsan industrial complex in Korea, which carries out proper inspection, many of the facilities have been used for 20 years. Also, most of the facilities where the accident occurred have been in operation for more than 20 years. Therefore, this study suggested criteria for classifying devices that have exceeded a certain period of use as obsolete facilities. In addition, quantitative risk assessment was conducted. The safety investment method using the cost-benefit analysis method was proposed in order to calculate the loss cost and reduce the risk by expressing the risks of the corresponding aged facility as an Economic index. By utilizing the method of cost-benefit analysis of old facilities using the quantitative risk assessment presented in this study, it can be expected to improve the performance and life of old facilities, improve production efficiency and reliability of the system of facilities, change the recognition of safety management costs, increase employee stability, and reduce loss costs.

• Korean Journal of Acupuncture
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• v.37 no.1
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• pp.14-23
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• 2020

Objectives : We investigated the efficacy and safety of miniscalpel acupuncture (MA) treatment combined with non-steroidal anti-inflammatory drugs (NSAIDs) for chronic neck pain (CNP) in an assessor-blinded randomized controlled pilot trial to establish a basis for larger-scale randomized controlled studies on this subject. Methods : Participants (n=36) were recruited and randomly allocated to the MA group, NSAIDs and combined treatment group. The MA group received MA three times over three weeks. The NSAIDs group was administered orally with zaltoprofen 80mg t.i.d. over three weeks. The combined treatment group received MA and zaltoprofen in the same manner as MA and NSAIDs groups. The primary outcome was pain as assessed by a visual analogue scale (VAS) and the secondary outcomes were assessed using the Neck Disability index (NDI), EuroQol 5-dimension questionnaire (EQ-5D), and Patients' Global Impression of Change scale (PGIC). Assessments were made at week 0 (baseline), 1, 2, 3 (primary end point) during treatment and at week 7 (4 weeks after the end of treatment). Results : 35 participants completed the study. No serious adverse event occurred and blood test results were within normal limits. The improvement of VAS and NDI was significantly greater in combined and MA group than that in NSAIDs group (p<0.017). The combined group showed better outcomes in EQ-5D at visit 2 and 5, in PGIC at visit 4 than the NSAIDs group (p<0.017). No significant differences were found between combined and MA group. Conclusions : Our results suggest that both combined and MA group can be more effective in improving pain control than NSAIDs group. A large-scale clinical study is warranted to further clarify these findings.