• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.6
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• pp.2211-2221
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• 2013

During the four river restoration project, several weirs were constructed in the four rivers to prevent drought and flood, to improve water quality, and to manage water resources. However, due to the weir construction, bed changes are produced in the upstream channel of installed weirs because the incoming flow velocity is reduced and sediment transport capacity is also lowered. Especially, since the Haman Weir is located in the lowest downstream section among newly installed weirs in Nakdong River, bed change and sedimentation problems are expected due to the mild slope and reduced velocity. Therefore, numerical simulation was performed to analyze flow and bed changes in the upstream channel of Haman Weir and to evaluate quantitatively sediment control methods for bed stabilization using CCHE2D model. As a result of flow and bed change simulation after installation of Haman Weir, the flow velocity at the initial condition was faster than the final bed condition with the specific simulation time and it was represented that the locations where bed changes were great were identical for all modeling conditions of flow discharge. In case of 4.5 m of water level lowered from 5.0 m of the management water level at Haman Weir for bed stabilization, the flow velocity was generally faster than the case of the management water level and the continuous erosion was developed at the most narrow channel section as the applied discharge and simulation period were increased. The channel width extension at the most narrow channel section was proposed in this study to prevent and stabilize continuos bed erosion. As a result of numerical analysis, there was no bed erosion after channel width extension and it was presented that the channel geometry extension was effective for bed stabilization at Haman Weir.

• Korean Journal of Microbiology
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• v.47 no.4
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• pp.356-363
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• 2011

The accidental releases of total petroleum hydrocarbons (TPH) due to oil spills frequently ended up with soil and ground water pollution. TPH may be degraded through physicochemical and biological processes in the environment but with relatively slow rates. In this study an attempt has been made to develop an integrated chemical and biological treatment technology in order to establish an efficient and environment-friendly restoration technology for the TPH contaminated soils. A Fenton-like reaction was employed as a preceding chemical treatment process and a bioaugmentation process utilizing a diesel fuel degrader consortium was subsequently applied as a biological treatment process. An efficient chemical removal of TPH from soils occurred when the surfactant OP-10S (0.05%) and oxidants ($FeSO_4$ 4%, and $H_2O_2$ 5%) were used. Bioaugmentation of the degrader consortium into the soil slurry led to an increase in their population density at least two orders of magnitude, indicating a good survival of the degradative populations in the contaminated soils ($10^8-10^9$ CFU/g slurry). TPH removal efficiencies for the Fenton-treated soils increased by at least 57% when the soils were subjected to bioaugmentation of the degradative consortium. However, relatively lower TPH treatment efficiencies (79-83%) have been observed in the soils treated with Fenton and the degraders as opposed to the control (95%) that was left with no treatment. This appeared to be due to the presence of free radicals and other oxidative products generated during the Fenton treatment which might inhibit their degradation activity. The findings in this study will contribute to development of efficient bioremediation treatment technologies for TPH-contaminated soils and sediments in the environment.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.4
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• pp.487-496
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• 2021

Full mouth rehabilitation is re-organizing the occlusion of the remaining teeth and missing teeth considering the functions, esthetics, and neuromuscular harmony. With the loss of multiple teeth, the patient's occlusal plane gradually collapses and the vertical dimension can be reduced. Since reduced vertical dimension can be a potential etiology of the temporomandibular joint and masticatory muscles, prosthetic restoration with increased vertical dimension is required. This case report is about a 68 years old patient with vertical dimension loss due to worn dentition and multiple loss of teeth. In this case, the loss of vertical dimension is assessed carefully using the digital dentistry technology. Using CAD software in digital analysis step, the occlusal plane was established and evaluated using several criteria. Orienting the position of the bone and teeth using CBCT image, patient's condition was visualized in 3 dimension and treatment planning was possible virtually. The information that matches the patient's condylar position with the articulator, which is the virtual face bow, is reproduced on the actual articulator, and evaluated again. After the evaluation, provisional prosthesis was fabricated and it was confirmed that the patient adapts without any abnormality. This was implemented as a final prosthesis. As a result, the patient obtained satisfying results, utilizing the benefits of digital dentistry technology and traditional methods.

• Korean Journal of Ecology and Environment
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• v.52 no.1
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• pp.50-64
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• 2019

Recently, quantitative analyses of food web structure based on carbon and nitrogen stable isotopes are widely applied to environmental assessments as well as ecological researches of various ecosystems, particularly rivers and streams. In the present study, we analyzed carbon and nitrogen stable isotope ratios of POM (both planktonic and attached forms), zooplankton, benthic macroinvertebrates and fish collected from 6 sites located at Nakdong River. Samples were collected from upstream areas of 5 weirs (Sangju, Gangjeong-Goryeong, Dalseong, Hapcheon-Changnyeong, and Changnyeong-Haman Weirs) and one downstream area of Hapcheon-Changnyeong Weir in dry season (June) and after rainy season (September). We suggested ranges of their carbon and nitrogen stable isotope ratios and calculated their trophic levels in the food web to compare their temporal and spatial variations. Trophic levels of organisms were relatively higher in Sangju Weir located at upper part of Nakdong River, and decreased thereafter. However, the trophic levels were recovered at the Changnyeong-Haman Weir, the lowest weir in the river. The trophic level calculated by nitrogen stable isotope ratios showed more reliable ranges when they were calculated based on zooplankton than POM used as baseline. The suggested quantitative ecological information of the majority of biological communities in Nakdong River would be helpful to understand the response of river food web to environmental disturbances and can be applied to various further researches regarding the quantitative approaches for the understanding food web structure and function of river ecosystems as well as restoration.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.6B
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• pp.565-575
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• 2011

The purpose of this study was to quantitatively evaluate the expression of both multi-metric qualitative habitat evaluation index (QHEI) and biological integrity index (IBI) for artificial structures eco-artificial fish reef (EAFR) for fishes asylum and habitat. Especially, both experimental evaluation and biological verification were performed in Water and Environmental Center's outdoor test-bed of Korea Institute of Construction Technology located in Andong-city, Gyeongsangbuk-do. The experimental conditions reflecting the situation of domestic river include the flow rate (e.g., $0.0{\sim}1.5m\;s^{-1}$), the width (e.g., 1.0~3.0 m), the depth (e.g., 0.05~0.70 m), and variable bed materials. Both QHEI and IBI were monitored for 8 months from May to December 2010. Whereas QHEI values were highest at experimental points of the E~F with an average of 83.1, those were lowest at B~C with an average of 78.1. However, QHEI values inside EAFR were more than 98.9, regardelss of space and time, and indicated more than the highest good of the state (Good) in the habitat. Overally, IBI values showed similar trend with QHEI, but were 44.2 in the winter dry season, compared to 32.8 of QHEI values. IBI values Also, IBI values inside EAFR were greater than those at the experimental channel by 5.7 to 11.4% and 18.7 to 34.8% in flow and stagnant conditions, respectively, indicating that EAFR can secure asylum and habitat for fish during the dry season. For comprehensive aquatic ecosystem assessment, the experimental channel showed generally fair conditions (Fair~Good), whereas EAFR showed good conditions (Good), suggesting that EAFR can be applied to aquatic ecosystem restoration and improvement.

• Journal of Chest Surgery
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• v.31 no.12
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• pp.1147-1158
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• 1998

Background: Portable cardiopulmonary bypass(CPB) technique has been used increasingly as a potent and effective option for emergency cardiopulmonary resuscitation(CPR) because it can maintain more stable hemodynamics and provide better survival than conventional CPR techniques. This study was designed to develop a prototype of Korean portable CPB system and, by applying it to CPR, to discriminate whether it would be superior to standard open-chest CPR. Material and Method: By using adult mongrel dogs, open-chest CPR(OCPR group, n=4) and portable-CPB CPR(CPB group, n=4) were compared with respects to restoration of spontaneous circulation(ROSC), hemodynamics, effects on blood cells, blood gas patterns, biochemical markers, and survivals. Ventricular fibrillation-cardiac arrest(VF-CA) of arrest(VF-CA) of 4 minutes followed by basic life support(BLS) of 15 minutes was applied in either group, which was standardized by the protocol of American Heart Association. Then, advanced life support(ALS) was applied to either group under the support of internal cardiac massage or CPB. ALS was maintained until ROSC was achieved but not longer than 30 minutes regardless of the presence of ROSC. All of the measured values were expressed as means±SD percent change from baseline. Result: During the early ALS, higher mean arterial pressure was maintained in CPB group than in OCPR group(90±19 vs. 71±32 %; p<.05) and lower mean pulmonary arterial pressure was also maintained in CPB group than in OCPR group(105±24 vs. 146±6%; p<.05). ROSC was achieved in all dogs. Post-ROSC levels of hematocrit, RBC, and platelet were decreased and plasma free hemoglobin was increased significantly in CPB group compared to OCPR group(p<.05). Changes in blood gas patterns, lactate, and CK-MB levels were not different between groups. Early mortality was seen in 3 dogs in OCPR group(survival time 31±36 hours) and 2 in CPB group(228±153 hours, p=ns). The remainders in both groups showed prolonged survival. Conclusion: These findings indicate that portable CPB can be effective to maintain stable hemodynamics during cardiac arrest, to achieve ROSC and to prolong survival. Further study is needed to refine the portable CPB system and to meet clinical challenges.

• Korean Journal of Environment and Ecology
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• v.28 no.2
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• pp.215-234
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• 2014

The purpose of this study is to identify the type and characteristics of the domestic natural streams in order to establish a basis for stream restoration and evaluation. To this end, 95 domestic natural stream areas, which have various natural environments, were selected except for the province of island and then the characteristics of natural environment, hydromorpholoy, plant and vegetation were investigated and analyzed in each stream area. As a result, 95 stream areas were classified into total 24 types according to 3 criteria such as stream size (4 types), altitude (3 types), bed material (5 types). Depending on altitude class that is the environmental factor showing the highest correlation with each stream types, the emergence of vegetation and plant, 24 stream types were reclassified into 3 types such as lowland (altitude less than 200m), mountain (altitude from 200m to 500m), highland (altitude more than 500m), and hydromorpholoy, plant and vegetation characteristics of each stream type were compared. First, when compared to the mountain and highland streams, the typical features of lowland streams were as follows: Stream size was large but bed material size was small and there were many valley forms where flood plane were developed well. In addition, the more large stream size was, the more cross-section width variability, bars and sinuosity were in good conditions. In lowland stream, representative vegetation community was Salix koreensis community. On the other hand, when compared to the lowland streams, the typical features of mountain and highland streams were as follows: Stream size was small but bed material was coarse-grained and its size was large. Mountain and highland streams valley form where flood plane was not developed well was narrow, and sinuosity and bars development were weak. Representative vegetation communities of mountain streams were Quercus serrata -, Quercus variabilis -, Styrax japonica community and representative vegetation communities of highland streams were Pinus densiflora -, Quercus mongolica -, Fraxinus rhynchophylla community.

• Journal of Korean Society of Forest Science
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• v.101 no.3
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• pp.387-394
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• 2012

The study was conducted to develop an effective forest resources use models for an alternate use of abandoned quarry by an attitude survey. According to the result of survey, a pessimistic view due to dust, noise pollution, and forest damage was 5% higher than an affirmative view by economic benefits from the development of quarry. The 42% of the respondents preferred the alternate use of abandoned quarry and the 25% of the respondents wanted an art and cultural space. The optimum size of alternate use was 5-10 ha (43%) with the requirement of nearby residents (32%). According to the SWOT analysis for abandoned quarry, the strength factors were an effective use of land, the content development of modern industrial inheritance + cultural and art fusion, attraction for nearby city and visitors, a harmony of beauty landscape and clean environment, and a sustainable increase of domestic and foreign visitors with the 5-day-work week. The opportunity factors were the improvement of traffic networks through KTX and local highway, the creation of the new growth engines with the establishment of artistic creation belts, the providing of unique cultural and art space through grafting of tour and education, the creation of local income through stone processed goods, and the vitalization of local development through eco-city. The weakness factors were a psychological remoteness and backwardness, and the weakness of staying tour infra. The threat factors were a poor financial support for sustainable development in nearby quarry and a modify of legal and institutional system for the alternated use of abandoned quarry. The developed restoration models for the alternate use in abandoned quarry are classified to a sculpture park, a waterfall and lake park, a rock-climbing, a sports park + forest park, a native botanical garden, a culture and art park, a complex park, a water storage site, a water storage site to extinguish forest fire, a geriatric hospital, an agricultural facility, and a school site types etc. The results suggest that the alternate use in the abandoned soil and stone quarry is needed to establish facility use models with consideration of user's preference.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.3
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• pp.154-167
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• 2014

The results of this study conducted to identify the substance, regional characteristics or landscaping of Namwon Yonghogugok, which is the only valley of Jiri Mountain, based on Kim Samun's 'Yonghokugok-Gyeongseungannae(龍湖九曲景勝案內)', 'Yongseongji(龍城誌)' and position, meaning of letters carved and projection technique by ArcGIS10.0 on the rocks are as below. The feature landscapes of the canyon of Yonghogugok, which is an incised meander and one of the Eight beautiful scenery of Namwon, ponds, cliffs and rocks generated with metamorphic rocks and granites weathered by rapids torrents. As a result of measuring the GPS coordinates of the letters carved on the rocks, excluding the 3 Gok Hakseoam and the distances based on the origin and destination of the letters carved on the rocks using the API(Application Programming Interface) function of Daum map, the total distance of Yonghogugok was 3.5km and the average distance between the each Gok was 436.5m. It is assumed that Yonghogugok was designated by Sarim(士林) of the Kiho School(畿湖學派) related to Wondong Hyangyak(元洞鄕約) which is the main agent of Yonghojeongsa(龍湖精舍), the forerunner of Yonghoseowon(龍湖書院), between the late Joseon Dynasty and the early Japanese colonial era, in 1927. Its grounds are the existence of Yonghoyeongdang mentioned on 'Yonghojeongsilgi'(龍湖亭實記), records of 'Haeunyugo(荷隱遺稿)', 'Yonghopumje(龍湖品題)' of Bulshindang(佛神堂), 'Yonghojeongsadonggu Gapjachun(龍湖精舍洞口 甲子春)' letters carved on the rocks and 'Yonghogugok-Shipyeong(龍湖九曲十詠)' posted on Mokgandang of Yonghoseowon. Comprehensively considering the numerous poetry society lists carved on the stone wall of Punghodae(風乎臺), the Sixth Gok Yuseondae, its stone mortar, 'Bangjangjeildongcheon(方丈第一洞天)' of Bulshindang and Gyoryongdam(交龍潭), the Yonghoseokmun(龍湖石門) letters carved on the rocks, Yeogungseok adjacent to the First Gok and Fengshui facilities, centered on Yonghoseowon and Yonghojeong, Yonghogugok can be understood as a unique valley culture formed with the thoughts of Confucianism, Buddhism, Taoism and Fengshui. 'Yonghogugok-Gyeongseungannae' provides very useful information to understand the place name, called by locals and landscaping aspects of Yonghogugok in the late Joseon Dynasty. In addition, the meaning of "Nine dragons" and even though 12 chu(湫: pond) of Yonghogugok Yongchudong including Bulyeongchu, Guryongchu, Isuchu, Goieumchu and Daeyachu are mentioned on Yongseongji, a part of them cannot be confirmed now. Various place names and facilities relevant to Guryong adjacent to Yonghogugok are the core of the place identity. In addition, the accurate location identification and the delivery of the landscaping significance of the 12 ponds is expected to provide landscaping attractiveness of Yonghogugok and become very useful contents for landscaping storytelling and a keyword of storyboard.

• Journal of dental hygiene science
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• v.9 no.5
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• pp.563-570
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• 2009

This study carried out the survey of the actual condition targeting 303 patients with execution of treatment after medical examination among patients who visited from January 2, 2008 to December 31, 2008 at dental hospital where is located in K region, and analyzed by using a program of SPSS13.0. The ratio of treatment in posterior was high with 76.9% in central incisor, 62.3% in the 1st bicuspids, and 45.3% in the first permanent molars as for health in the right teeth of maxillary, and with 77.9% in central incisor, 64.4% in the 1st bicuspids, and 47.6% in the first permanent molars as for the left teeth. In the lower jaw, the ratio of treatment in posterior was high with 92.1% in central incisor, 73.9% in the 1st bicuspids, and 42.6% in the first permanent molars as for health in the right teeth, and with 92.1% in central incisor, 75.9% in the 1st bicuspids, and 43.2% in the first permanent molars as for the left teeth. The upper left cuspid was treated in older patients by age(${\chi}^2=32.33$, p=0.000), in the more patients with high blood pressure(${\chi}^2=12.60$, p=0.000), and in case of systemic disease. The significant difference was shown(${\chi}^2=6.37$, p=0.012). The older patients led to being treated cuspid among right teeth in the lower jaw. The significant difference was shown according in the more patients with high blood pressure(${\chi}^2=8.26$, p=0.004). The left cuspid in the lower jaw was treated in the older patients by age the statistically significant difference was shown(${\chi}^2=12.10$, p=0.007).