• Journal of the Korean Society of Marine Environment & Safety
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• v.15 no.2
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• pp.91-98
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• 2009

The long-term water-quality change of Asan Bay by the influx of polluted disposal water was predicted through a simulation with an Eco-hydrodynamic model. Eco-hydrodynamic model is composed of a multi-level hydrodynamic model to simulate the water flow and an ecosystem model to simulate water quality. The water quality simulation revealed that the COD(Chemical Oxygen Demand), dissolved inorganic nitrogen(DIN) and dissolved inorganic phosphorus(DIP) are increased at 5 stations for the subsequent 6 months after the influx of the effluent. COD, DIN and DIP showed gradual decreases in concentration during the period of one to two years after the increase of last 6 months and reached steady state for next three to ten years. Concentration levels of COD, DIN, and DIP showed the increase by the ranges of $11{\sim}67%$, $10{\sim}67%$, and $0.5{\sim}7%$, respectively, which represents that the COD and DIN are the most prevalent pollutants among substances in the effluent through the sewage treatment plant. The current water quality of Asan Bay based on the observed COD, TN and TP concentrations ranks into the class II of the Korean standards for marine water quality but the water quality would deteriorate into class III in case that the disposal water by the sewage plant is discharged into the Bay.

• Journal of Digital Convergence
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• v.14 no.9
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• pp.287-299
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• 2016

The electronic transactions over the Internet are growing across the world recently. There have been a lot of identity theft incidents during these online transactions nowaday. Therefore, a high level of identity proofing shall be carried out when using online services to deal with these matter. To prevent this kind of incident, i-PIN was introduced in Korea, which is used as an Internet Personal Identification Number. The i-PIN is designated to provide an online identification of the Internet users. As such, the unique identification numbers are provided to the internet service providers. This paper is to analyze the capabilities that the i-PIN provides, to propose the assurance security model for i-PIN. Furthermore, the security analysis results are presented. The result of this paper can be applicable to improve the applicabilities of the i-PIN.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.1C
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• pp.33-42
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• 2006

Lots of river embankments or levees in Korea are quite so old and unknown the origin even. The river deposits, moreover, obtainable easily somewhere were used for materials of embankment without any technical considerations such as the influence soil properties and construction methods on embankment stability. It's natural that safety would be threatened if the water level rises due to flood or rainfall when it comes to abnormal weather conditions, especially. From this point of view, enlargement of embankment, irrigation works, etc. are in progress recently at the situation from a reinforcement work. However, taking influence of soil properties and construction methods on embankment stability into account against cracking or piping is still insufficient. Fragmentary design criteria or irrational construction methods are applied rather as the case may be. In this study, therefore, a way to estimate piping and cracking resistance (Sherard, 1953) has been introduced and reevaluated for practical use with an eye to material properties and its applicability to piping-experienced embankments was examined. Piping possibility was also examined in the present design criteria and compared. In view of the results achieved, it reflects that both yield piping possibility. But it's still necessary to complement how to judge and verify piping resistance of given soils with gradation curves by the representative curve, quantitatively and that piping resistance should consider compaction effects as well.

• Journal of Convergence for Information Technology
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• v.11 no.8
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• pp.84-91
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• 2021

In the 21st century, a number of storm and flood disasters caused by rapidly changing climate change is increasing, and the number of flood accidents at construction sites is also increasing. However, no specific reduction measures have been presented and thereby safety management to prevent flood accident need to be improved. Therefore, in this study, the inundation pattern by downpour at the excavation site was interpreted and the inundation risk quantification method was used to classify the risk magnitude. Finally, using the fish-bone diagram, we derived the major reasons of inundation accident at construction site systematically. The simulation results showed that the inundation depths of small-scale excavation sites and excavation sites exceeded 3 m due to the fluid flowing through the excavation surface. In addition, depending on the excavation site, a high velocity temporarily observed and decreased due to the storage effect, or high velocity surpassing 10 m/s continued. Since this type of flooding can pose a risk to most or all workers, if proper management measures are insufficient, fatal damage to life and property could occur. Consideration of the roots of these disasters is judged to be helpful in understanding the causes of inundation accidents that result in casualties and presenting accident reduction measures.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.317-324
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• 2020

In this study, a simplified equation for settlement evaluation suitable for the special conditions of a counter facility is suggested. Recently, counter facilities, especially breakwaters, are constructed on soft ground in distant seas as new-port development projects. A counter facility that resists the external forces by self-weight settles easily when constructed on soft ground. Settlement in a counter facility and breakwater is not an important factor for maintenance than a land facility. On the other hand, the current settlement evaluation criteria are excessive for conducting a safety inspection. A settlement evaluation from a safety inspection followed by "Detailed Guidelines for a safety inspection on a counter facility" is used. A simplified equation was proposed to calculate the maximum settlement by applying the allowable residual settlement or settlement stability evaluation results. The suitability of the simplified equation was assessed compared to the assessed rating from the settlement survey results. The proposed simplified equation showed that the settlement evaluation rating had been upgraded. The proposed simplified equation is expected to be used to evaluate the practical structural stability and functional performance.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.1
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• pp.100-118
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• 2021

In this study, PM accidents (1,603case) and bicycle accidents (14,672case) that occurred in the last three years were analyzed to determine the characteristics of PM traffic accidents. In particular, PM traffic accidents were divided into perpetrators and victims to determine the characteristics in detail. For PM accidents, the analysis was conducted on the status of each road grade, road type, weather condition, accident type, day and night occurrence, and vehicle type. The number of PM accidents that occurred in 2019 increased by 129%, and deaths increased by more than 200% compared to the previous year. The proportion of pedestrian accidents among PM traffic accidents was higher than that of bicycle accidents. Therefore, regulations on PM traffic are necessary. For the 20 deaths of PM, a detailed analysis was conducted to analyze the factors of traffic accidents. PM fatalities occurred in 50% of vehicle accidents, and 7 out of 10 vehicle accidents occurred at night. This is believed to have been caused by falling or overturning due to an obstacle, such as a depression in the road pavement or a speed bump.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.2
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• pp.115-120
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• 1999

This experiment was carried out to investigate the effects of additives on the quality of alfalfa(Medicago sativa L.) silage at the forage experimental field, National Livestock Research Institute, RDA, Suwon in 1996. The experiment was arranged in a randomized block design with three replications. The treatments consisted of different additives(control, formic acid, molasses, inoculant A and inoculant B). Crude protein(CP) and Nitrogen free extract(NFE) content of alfalfa silage with additives were higher compared with those obtained control, but Crude ash(CA) and Crude fiber(CF) content of control(11.5 and 39.6%) were higher than those of additive treated plots. ADF and NDF contents of control silage were the highest as 36.2 and 48.6%, respectively, and increased by 4% compared with those obtained before ensiling. The acidity(pH) of control was the highest(5.45), but the lowest in inoculant A(4.32). Inoculant teratment significantly reduced acidity of silage compared with control. DM content of control silage was the lowest but DM loss of control silage was higher than that of additive treated silage. Ammonia-N content was the highest at formic acid treatment and level of Lactobacillus was decreased at control and formic acid treated silage. Total organic acid and lactic acid content of inoculant A and inoculant B were higher than those of other treated plots. The results of this study indicate that the treatment of LAB(Lactic acid bacteria) could be recommended as producing high quality of alfalfa silage.

• Tuberculosis and Respiratory Diseases
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• v.44 no.4
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• pp.776-784
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• 1997

Background : Various combinations of treatment modalities have been reported in stage III non-small cell lung cancer (NSCLC). however, the standard treatment modality has not established yet. Recently, the efficacy of concurrent chemotherapy and radiation therapy has been reported in locally advanced lung cancer. We evaluate the response rate, toxicity, and survival of concurrent chemotherapy with etoposide and cisplatin(EP) and radiation therapy for unresectable stage III NSCLC. Method : Between October 1995 and December 1996, 32 patients with histologically proven unresectable stage III NSCLC without malignant pleural effusion were entered into this study. Twenty-nine patients were eligible for the response, survival, and toxicity analysis. Induction was two cycles of chemotherapy with etoposide and cisplatin plus concurrent chest RT to 4500cGy. Resection was attempted if the clinical response offered surgical resectability. Boost radiation therapy upto 5940cGy and one cycle of EP were performed if the disease were stable or responsive but still unresectable. Results : Of 29 eligible patients, 22(75.9%) showed partial response(PR). The progression free interval was 6.3months(range 1.1 to 19.5months). Surgical resection was performed in one patient. The median survival was 12.1months and one-year survival rate was 50.6%. The major toxicity was leukopenia($\geq$ grade 3, 46%). Thrombocytopenia over grade 3 was found in 11%. Radiation pneumonitis occurred in 13 patients(46%). Conclusion : Concurrent chemotherapy(EP) plus radiotherapy was effective and tolerable in the treatment of unresectable stage III NSCLC.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.2
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• pp.68-81
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• 2014

This study was conducted to identify the spacialty, to illuminate the existence and values of Myeongwoldae(明月臺) and Forest Myeongwol, and to suggest the sustainable usage, preservation and management plans with the purpose of ecological and cultural landscaping characteristic and value identification. The result of the study is as follows. Castle Myeongwol and Port Myeongwol shows the status of Hallim-eup Myeongwol District which is the administrative center of western Jeju as well as is the fortress. Building Wolgyejeongsa and School Woohakdang, the head temple of education and culture, located in Myeongwol District represents the spaciality of Myeonwol-ri which was the center of education. Stand Myeongwol is one of the most representative Confucian cultural landscapes in Jeju Island and the field of communion with nature where scholars enjoy poetries, nature, changgi(Korean chess), and go in the Joseon Dynasty period. It was found that the current relics of Myeongwoldae was recovered through the maintenance project conducted by Youth Group Myeongwol composed with Hongjong-si(洪鍾時) as the center during the Japanese colonial era in 1931. It seems that the stonework of Myeongwoldae composed of three levels in the order of square, octagon, and circle based on the heaven-man unity theory of Confucianism and the octagon in the middle is the messenger of Cheonwonjibang(天圓地方), in other words, between the square-shaped earth and the circle-shaped sky. It is assumed that both Grand Bridge Myeongwol and Bridge Myeongwol were constructed as arched bridges in early days. Bridge Myeongwol is the only arched bridge remaining in Jeju Island now, which has the modern cultural heritage value. In Forest Myeongwol, 97 taxa of plants were confirmed and in accordance with 'Taxonomic Group and Class Criteria of Floristic Specific Plants', eight taxa were found; Arachniodes aristata of FD IV and Ilex cornuta, Piper kadsura, Litsea japonica, Melia azedarach, Xylosma congestum, Richosanthes kirilowii var. japonica, Dichondra repens, Viburnum odoratissimum var. awabuki of FD III. Otherwise, 14 taxa of naturalized plants including Apium leptophylihum which is imported to Jeju Island only were confirmed. In Forest Myeongwol, 77 trees including 41 Celtis sinensis, 30 Aphananthe aspera, two Wylosma congestum, a Pinus densiflora, a Camellia japonica, a Melia azedarach, and an Ilex cornuta form a colony. Based on the researched data, the preservation and plans of Myeongwoldae and Forest Myeongwol is suggested as follows. Myeongwoldae, Bridge Myeongwol, and Forest Myeongwol should be managed as one integrated division. Bridge Myeongwol, an arched bridge which is hard to be found in Jeju Island is a high-standard stonework requiring long-term preservation plans. Otherwise, Grand Bridge Myeongwol that is exposed to accident risks because of deterioration and needs safety diagnosis requires measures according to the result of precise safety diagnosis. It is desirable to restore it to a two-sluice arched bridge as its initial shape and to preserve and use it as a representative local landmark with Stand Myeongwol. In addition, considering the topophsis based on the analysis result, the current name of Jeju Special Self-Governing Province Monument No. 19 'Myoengwol Hackberry Colony' should change to 'Myeongwol Hackberry-Muku Tree Colony'. In addition, the serial number system which is composed without distinction of hackberry and muku tree should be improved and the regular monitoring of big and old trees, specific plants, and naturalized species is required.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.4
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• pp.633-637
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• 2001

Local anesthesia procedure in pediatric dentistry using needle-tipped syringes is stressful and painful for the child patients The Syrijet Mark II (Mizzy Inc. USA) is a jet injection instrument, which uses high pressure to propel fluids into soft tissue without the use of a hollow neeldle, so it seems to be able to reduce the injection phobia of the child patients. The authors compared the Syrijet with the conventional syringe by assessing the pain level after local anesthetic procedures using CAS(color analogue scale) which was developed from VAS(visual analogue scale). The result showed that the pain was reduced by the use of syrijet. The advantages of syrijet were no use of neeldes, the reuse of the anesthetic cartridge, and the safety to nerves and vessels. The disadvantages were the large size, the high price, and the need of skill to use.