• Journal of the Korean GEO-environmental Society
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• v.17 no.10
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• pp.23-31
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• 2016

Grout is generally operated with low viscous material similar to water, but grout for micro crack with high viscous materials and high injection pressure is gradually increased under the development of underground and subsea space. In order to estimate grouting injection performance considering crack width, viscosity of grouting materials, and injection pressure, there should be a reliable standard laboratory testing method. In this paper, theoretical injection mechanisms of grouting materials are presented as radial and linear flows, and laboratory testing apparatus are introduced to simulate each flow case. Radial flow is simulated by using acrylic disk plates which are able to spread grouting material radially from the center of the disk plates, and linear flow is simulated by using stainless parallel plane plates which are able to spread grouting material linearly. Apparatus are consist of upper and lower plates and industrial films with different thickness are placed between plates in order to simulate various crack widths. Laboratory verification tests with these apparatus were conducted with tap water (1cP at $20^{\circ}C$) as an injection material. Through the laboratory testing results, the best laboratory testing method is recommended in order to estimate grouting injection performance.

• Journal of Korean Foot and Ankle Society
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• v.16 no.2
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• pp.94-100
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• 2012

Purpose: The purpose of this study is to analyze the clinical features of distal tibia fractures and to evaluate the treatment outcomes of minimally invasive plate osteosynthesis (MIPO). Materials and Methods: From January 2004 to December 2009, 84 cases of 81 patients treated with plate fixation for distal tibia fracture were enrolled in this retrospective review. We investigated age, sex, injury mechanism, fracture patterns, and complications, and the clinical features were analyzed. To evaluate the treatment outcomes of MIPO, we divided into two groups. MIPO group consisted of 55 patients were treated with MIPO technique and conventional group consisted of 18 patients were treated with open reduction and internal fixation with conventional anterolateral plating. The results were compared between two groups by assessing bony union time, operation time, amount of blood loss, range of ankle motion, clinical score by American Orthopaedic Foot and Ankle Society (AOFAS) score, and post-operative complications. Results: The mean age of 81 patients with distal tibia fracture was 54.8 years. According to AO classification, A1:2:3 were 16, 20, 16 patients, B1:2:3 were 2, 8, 7, C1:2:3 were 1, 3, 11 patients. According to injury mechanism, slip down injury was patients, traffic accident was 26, fall from height injury was 14 patients respectively. The type A fractures were lower energy trauma and more older patients. The type C fractures were higher energy trauma and younger patients. MIPO group was better than conventional group in operative time, blood loss, bony union time, and ankle joint motion. In complications, MIPO group showed no nonunion and infection, one malunion, one skin necrosis, nine skin irritations, and one screw breakage. Conventional group showed two nonunion, four infections, two skin necrosis, and one metal failure. Conclusion: Distal tibial fractures caused by low energy trauma were on the increase. Minimal invasive plate osteosynthesis was shorter bony union time and operation time, less blood loss, and larger ankle motions than conventional open reduction and plate fixation.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.3
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• pp.237-243
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• 2015

In this study, the effects of the mixing ratio of emulsified fuel on the droplet evaporation and spray behavior characteristics were analyzed. A surfactant comprising span 80 and tween 80 mixed at a 9:1 ratio was used for the emulsified fuel. The fuel and surfactant were mixed at a ratio of 3:1 for the emulsified fuel. In addition, considering the mixing ratio of the surfactant, the mixing ratio of $H_2O_2$ in the emulsified fuel was set as EF (emulsified fuel)0, EF2, EF12, EF22, EF32, and EF42. To observe the evaporation characteristics, droplets of the emulsified fuel were dropped on a heating plate and observed using scattered light and a Schlieren system. In addition, to analyze the effect of the $H_2O_2$ mixing ratio, the behavior characteristics of the evaporative free spray were investigated in the mixing ratio range of EF0 to EF22 using a constant volume chamber with heaters. Consequentially, it was found that in the case of EF22, the free spray development of the emulsified fuel was faster than that of EF0 (diesel only) because of the promotion of the evaporation due to the phase change in the peroxide contained in the emulsion fuel.

• Fire Science and Engineering
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• v.28 no.4
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• pp.81-88
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• 2014

This study identified the complaint ratio of musculoskeletal symptom by 119 EMTs and investigated the work risk extent through ergonomics evaluation about the patient transport works, which cause work-related musculoskeletal disorders (WMSDs) to 119 EMTs. For this, the complaint ratio of musculoskeletal symptom utilized questionnaire tool based on KOSHA Code H-30-2008 and the risk extent about the patient transport work evaluated by using ergonomics evaluation tools such as OWAS, RULA and REBA. According to the study result, 60.9% of 119 EMTs experienced musculoskeletal symptom. Among them, the symptom on back was the most common (36.1%). The work, which mostly causes WMSDs, has been found as patient transport work (48.4%). Among the patient transport motion, loading/unloading of ambulance cot to/from ambulance and the lifting of patient by stretcher were OWAS risk-level 3 and RULA/REBA risk-level 3 to 4. Among the patient transport environment, carrying patient on stairway using emergency mini-stretcher, moving patient in vehicle using spine board and piggy-back carrying or cradle carrying patient on stairway or slope way were OWAS, RULA, REBA risk level 3 to 4. It is suggested that immediate improvement in work postures for these works should contribute to prevention against WMSDs to 119 EMTs.

• The Journal of the Petrological Society of Korea
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• v.18 no.2
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• pp.93-114
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• 2009

Lithological and petrochemical characteristics and tectonic setting of the Cretaceous volcanic rocks in Hampyeong area located in the southwestern part of Okchon Zone, were studied by field survey and petrochemistry of major, trace, and rare earth elements. The $SiO_2$contents of the volcanic rocks range from 50.8 to 77.2wt.%. With increasing $SiO_2$, $Al_2O_3$, $Fe_2O_3\;^T$, $TiO_2$, MnO, CaO and MgO contents decrease and $K_2O$content increase, but $Na_2O$content is scatter to the trend. According to TAS and AFM diagrams, the Cretaceous volcanic rocks are calc-alkaline series. On the discrimination diagram of $K_2O$versus $SiO_2$, the volcanic rocks belong to high-K rocks series. The trace element compositions and REE patterns of the volcanic rocks, characterized by a high LILE/HFSE ratio and enrichments in LREE, indicate that they are typical of continental margin arc calc-alkaline volcanic rocks associated with the subduction environment. The ratios of Ba/Ta and Ba/La indicate that they are associated with volcanic arc-related magmatism. The Cretaceous volcanic rocks in Hampyeong area might be located in the Eurasian continental margin, related to the Pacific type tectonic environment during the Cretaceous times.

• Journal of Korean Foot and Ankle Society
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• v.24 no.2
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• pp.87-93
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• 2020

Purpose: This study evaluated the clinical results of surgical treatment with minimally invasive plate osteosynthesis for treating displaced intra-articular fractures of the calcaneus in comparison with conventional lateral extensile approach plate osteosynthesis. Materials and Methods: Of 79 cases of Sanders type II or III calcaneus fractures, 15 cases treated with the minimally invasive calcaneal plate (group M) and 64 cases treated with lateral extensile approach calcaneal plate (group E) were identified. After successful propensity score matching considering age, sex, diabetes mellitus history, and Sanders type (1:3 ratio), 15 cases (group M) and 45 cases (group E) were matched and the demographic, radiologic, and clinical outcomes were compared between the two groups. Results: The median time of surgery from injury was 2.0 days in group M and 6.0 days in group E (p=0.014). At the six months follow-up, group M showed results comparable with those of group E in radiographic outcomes. In the clinical outcomes, group M showed better postoperative American Orthopaedic Foot and Ankle Society (AOFAS) and visual analogue scale (VAS) scores than did group E (p=0.001, p=0.008). A greater range of subtalar motion was achieved at the six months follow-up in group M (inversion 20.0° vs. 10.0°, p=0.002; eversion 10.0° vs. 5.0°, p=0.025). Although there were no significant differences in complications between the two groups (1 [6.7%] vs. 7 [15.6%], group M vs. group E; p=0.661), there was only one sural nerve injury and no wound dehiscence and deep infection in group M. Conclusion: Minimally invasive plate osteosynthesis showed superior clinical outcomes compared with that of the conventional lateral extensile approach plate osteosynthesis in Sanders type II or III calcaneus fractures. We suggest applying minimally invasive plate osteosynthesis in Sanders type II or III calcaneus fractures.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.1
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• pp.33-38
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• 2013

Occlusal plane is a sagittal expression of dental arch form, and it composes the shape of occlusion, which is one of the most important elements of Maxillo-oral system. In this case, vertical, horizontal coordinates of bionic-median-sagittal plane was produced in articulator, and to achieve relation of left and right position of upper, lower teeth and deficits in alveola, Shilla system was used to reconstruct occlusal plane. In this case, a 41 year-old male patient visited for fracture of 10 unit metal-ceramic fixed partial denture of upper anterior teeth and for overall treatment. Clinical, radiographical, model examination was held, full mouth rehabilitation was achieved by placing dental implant. Maxillo-oral relation was recorded using Gothic arch Tracer complex and were mounted. And for the next step, we estimated original occlusal plane using Shilla system. After analysis we produced diagnosis wax pattern. On the basis of this, radiography stent was manufactured and dental implant was placed, and temporary prosthesis was made by using diagnosis wax pattern. Cross mounting and anterior guiding table were performed in order to reproduce temporary restoration morphology and bite pattern, followed by final restoration made of all ceramic crown with zirconia coping. As stated above, appropriately esthetic and functional results can be seen in using Shilla system in diagnosis and treatment procedure of full mouth rehabilitation patient.

• Journal of Korean Library and Information Science Society
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• v.35 no.3
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• pp.79-94
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• 2004

This research studied the preservation treatment of the papered literature the national treasure 745-9 $\ulcorner$Keumganggyung-samgahae$\lrcorner$, discovered in 1995 from the Four Devas of Borimsa Buddhist Temple at Jangheung County, in the viewpoint of the bibliography. The overall features of the $\ulcorner$Keumganggyung-samgahae$\lrcorner$ were of 25.3cm width, 38.9cm height 1.5cm depth, 58 pages and of high-fine yellow-brown colored reef paper. The book was ruined physically in the shape and color. The covers of the book were deeply stained by the permeated rain and some internal pages were changing into brown color by corrosion. The treatment policies were； maintaining the status quo and capable repeated treatment. And the preservation treatment was done in the sequences of 1) 1st cleaning process, 2) repairing and correcting, 3) 2nd cleaning and preservation 4) cutting, binding the book and making the envelope and wood box. The post-preservation features of $\ulcorner$Keumganggyung-samgahae$\lrcorner$ were； total 64 pages and the size being 25.8 cm width 39.4cm of lenght, and 1.9cm of depth.

• Journal of Korean Foot and Ankle Society
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• v.15 no.2
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• pp.62-67
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• 2011

Purpose: The authors evaluated the differences between K-wires and Cannulated screw, plate for fixing the proximal metatarsal chevron osteotomy of moderate and severe hallux valgus. Materials and Methods: There were 62 patients (79 feetz) who were moderate and severe degree hallux valgus according to the classification of Mann. They all got the proximal chevron osteotomy when correcting the deformity. We divided the patients into 4 groups, Two K-wire fixed group as A, one cannulated screw fixed group as B. Two cannulated screw fixed group as C, Plate fixed group as D, Group A were patients (26 feet) and Group B were patients z(9 feet), Group C were patients (31 feet) and Group D were patients (13 feet). Preoperative, postoperative and follow-up hallux valgus angle (HVA) and intermetatarsal angle (IMA) were measured for each patient. ANOVA test and Student t-test were done for statistical analysis. Results: Mean follow up period was 43.8 months (range: 12~82 months). Preoperative mean IMA was $16.4{\pm}3.5$, $17.7{\pm}11.3$, $17.3{\pm}5.9$ and $16.6{\pm}2.3$ degrees in respectively group A, B, C, D. Immediate postoperative mean IMA was $5.6{\pm}3.4$, $7.3{\pm}4.4$, $7.6{\pm}4.4$ and $6.7{\pm}2.8$ degrees in respectively group A, B, C, D. The final mean IMA was $8.9{\pm}4.5$, $15.2{\pm}7.5$, $10.3{\pm}4.4$ and D $7.7{\pm}3.5$ degrees in respectively group A, B, C, D. There were significant statistical increase in final mean IMA of group B and C (p<0.05). Conclusion: The IMA was significantly increased in the group which used one or two cannulated screw for fixation on follow up, therefore more caution should be needed when using one or two cannulated screw fixation technique after proximal chevron osteotomy.

• The Journal of the Petrological Society of Korea
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• v.14 no.4 s.42
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• pp.212-225
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• 2005

This study has been designed to elucidate the morphology of Jisagae columnar joints and the petrography and petrochemistry of Daepodong basalt in Jeju Island, distributed along the 3.5 km-long coast from Seongcheonpo to Weolpyeongdong. Colonnade of the Jisagae columnar joint typically occurs within the upper part of a flow and consists of relatively well-formed basalt columns. Most columns are straight with parallel sides and diameters from 100 cm to 205 cm, $130\~139\;cm$ in maximum. Length of the columns extends up to 20 m. Most columns tend to have 6 or 5 sides but sometimes they have as few as $3\~4$ or as many as 7 or 8 sides. The Daepodong basalt consists of plagioclase, olivine, orthopyroxene, clinopyroxene, ilmenite and magnetite. Plagioclase is labradorite, clinopyroxene is augite, orthopyroxene is bronzite and olivine is chrysolite and hyalosiderite. The Daepodong basalt shows porphyritic texture with matrix of mainly intersetal texture. The Daepodong basalt is plotted into alkali rock series on the TAS diagram. The tectonic setting of the Daepodong basalt represents within plate environment.