• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.49 no.3
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• pp.107-113
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• 2023

Bimaxillary transverse width discrepancies are commonly encountered among patients with dentofacial deformities. Skeletal discrepancies should be diagnosed and managed appropriately with possible surgical corrections. Transverse width deficiencies can present in varieties of combinations involving the maxilla and mandible. We observed that in a significant proportion of cases, the maxilla is normal, and the mandible showed deficiency in the transverse dimension after pre-surgical orthodontics. We designed novel osteotomy techniques to enhance mandibular transverse width correction, as well as simultaneous genioplasty. Chin repositioning along any plane is applicable concomitant with mandibular midline arch widening. When there is a requirement for larger widening, gonial angle reduction may be necessary. This technical note focuses on key points in management of patients with transversely deficient mandible and the factors affecting the outcome and stability. Further research on the maximum amount of stable widening will be conducted. We believe that developing evidence-based additional modifications to existing conventional surgical procedures can aid precise correction of complex dentofacial deformities.

• Journal of Korean Society of Disaster and Security
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• v.14 no.2
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• pp.61-75
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• 2021

Recently, as the occurrence frequency of sudden floods due to climate change increased and the aging of the existing spillway, it is necessary to establish a plan to utilize an auxiliary spillway to minimize the flood damage of downstream rivers. Most studies have been conducted on the review of flow characteristics according to the operation of auxiliary spillway through the hydraulic experiments and numerical modeling. However, the studies on examination of flood damage in the downstream rivers and the stability of the revetment according to the operation of the auxiliary spillway were relatively insufficient in the literature. In this study, the stability of the revetment on the downstream river according to the outflow conditions of the existing and auxiliary spillway was examined by using 3D numerical model, FLOW-3D. The velocity, water surface elevation and shear stress results of FLOW-3D were compared with the permissible velocity and shear stress of design criteria. It was assumed the sluice gate was fully opened. As a result of numerical simulations of various auxiliary spillway operations during flood season, the single operation of the auxiliary spillway showed the reduction effect of maximum velocity and the water surface elevation compared with the single operation of the existing spillway. The stability of the revetment on downstream was satisfied under the condition of outflow less than 45% of the design flood discharge. However, the potential overtopping damage was confirmed in the case of exceeding the 45% of the design flood discharge. Therefore, the simultaneous operation with the existing spillway was important to ensure the stability on design flood discharge condition. As a result of examining the allocation ratio and the total allowable outflow, the reduction effect of maximum velocity was confirmed on the condition, where the amount of outflow on auxiliary spillway was more than that on existing spillway. It is because the flow of downstream rivers was concentrated in the center due to the outflow of existing spillway. The permissible velocity and shear stress were satisfied under the condition of less than 77% of the design flood discharge with simultaneous operation. It was found that the flood damage of downstream rivers can be minimized by setting the amount allocated to the auxiliary spillway to be larger than the amount allocated to the existing spillway for the total outflow with simultaneous operation condition. However, this study only reviewed the flow characteristics around the revetment according to the outflow of spillway under the full opening of the sluice gate condition. Therefore, the various sluice opening conditions and outflow scenarios will be asked to derive more efficient utilization of the auxiliary spillway in th future.

• Archives of Plastic Surgery
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• v.37 no.5
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• pp.626-632
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• 2010

Purpose: Nasal bone fractures are often classified as minor injury. However, the incidence of posttraumatic nasal deformity remains alarmingly high. It is because of unnoticed septal fracture. This study was conducted to determine the necessity of septoplasty for patients with nasal bone fracture accompanying grade I septal fractures. Methods: Among 105 patients with nasal bone fractures, 52 who had grade I septal fracture were diagnosed based on physical examination and computed tomography. Patients' age ranged from 14 to 65 years (mean 29.25 years), and 35 were male and 17 female. Patients were divided into 2 groups according to surgical treatment methods: patients who underwent closed reduction only (group 1, n=28) and those who underwent simultaneous closed reduction and septoplasty (group 2, n=24). The treatment outcomes were evaluated by comparing changes in nasal airway volume measured by acoustic rhinometry before the surgery, 3 months and 6 months after the surgery according to the timing of surgical repair and surgical treatment methods. Results: Nasal airway volume increased after the surgery by 17.8% in 3 months after the surgery, 25.2% in 6 months in group 1 and by 22.7% in 3 months, 35.8% in 6 months in group 2. The increase in airway volume after the surgery by 26.3% in 3 months after the surgery, 34.2% in 6 months after the surgery in operation within 1 week after trauma and by 12.1% in 3 months, 22.2% in 6 months after the operation later 1 week after trauma. The difference was statistically significant. Three patients in group 1 complained of intermittent nasal obstruction, two of whom showed a decrease in nasal airway volume by acoustic rhinometry. Conclusion: Most patients with nasal bone fractures accompanying grade I septal fractures have been treated with closed reduction in clinical settings. However, the results of this study suggest that septoplasty be performed after a correct diagnosis of septal fracture is made through comprehensive physical examination and computed tomography. Septoplasty is important to obtain more favorable outcomes and reduce complication.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.5
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• pp.1-7
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• 2012

The main purpose of this research is to evaluate the effect of light quality on the growth and physiological activities of Laurus nobilis plants growing indoors, the L. nobilis seedlings were grown under four types of lighting for 180 days. The seedlings were grown under 4 different treatments((n=9 seedlings per treatment): control, control supplemental UV-B irradiated(+UV), FR reduced(-FR) and simultaneously supplemental UV-B irradiated and FR reduced(+UV-FR)). It was found that UV-B irradiation(+UV) reduced dry weight and leaf area, and increased leaf thickness and the amount of UV-absorbing compounds per unit leaf area. In contrast, a reduction in far-red(FR) light did not affect any of these parameters. Interestingly, however, the elongation growth and net photosynthetic rate of the L. nobilis seedlings grown under simultaneous UV-B irradiation and FR reduction(+UV-FR) were significantly decreased than the control treatment. From these results, it is concluded that the light quality has a large effect on the indoor growth of L. nobilis. This study can suggest basic information for managed in the L. nobilis in indoor using light quality.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.4
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• pp.111-120
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• 2014

The aim of this study is to develop an integrated urea-SCR catalytic filter system for reducing soot and $NO_X$ emissions simultaneously in diesel engines. In this study, the characteristics of exhaust emissions relative to reactive activation temperature under four kinds of engine loads are experimentally investigated by using a four-cycle, four-cylinder, direct injection type, water-cooled turbo intercooler ECU common-rail diesel engine with the integrated urea-SCR $MnO_2-V_2O_5-WO_3/TiO_2/SiC$ catalytic filter system operating at three kinds of engine speeds. The urea-SCR reactor is used to reduce $NO_X$ emissions, and the catalytic filter system is used to reduce soot emissions. The reactive activation temperature is very important for reacting a reducing agent with exhaust emissions. The reactive activation temperatures in this experiment is applied to 523, 573 and 623 K. The fuel is sprayed by the pilot and main injections at the variable injection timing between BTDC $15^{\circ}$ and ATDC $1^{\circ}$ according to experimental conditions. It is found that the $NO_X$ conversion rate is the highest as 83.9% at the reactive activation temperature of 523 K in all experimental conditions of engine speed and load, and the soot emissions shown by the average reduction rate of approximately 93.3% are almost decreased below 0.6% in all experimental conditions regardless of reactive activation temperatures. Also, the THC and CO emissions by oxidation reaction of Mn, V and Ti are shown in the average reduction rates of 70.3% and 38% regardless of all experimental conditions.

• Applied Chemistry for Engineering
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• v.10 no.2
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• pp.237-241
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• 1999

Nickel was impregnated on the $SiO_2$ and $Al_2O_3$ supports and applied to the reduction reaction of CFC-113 ($CF_2Cl$-$CFCl_2$) with hydrogen to 3FCl ($CF_2$=CFCl, CFC-1113). The conversion was rapidly declined on the Ni/$SiO_2$(or $Al_2O_3$) and the deactivation accelerated as the increase of Ni content. However, the selectivity of 3FCl was maintained at around 80% level. The simultaneous coprecipitation of copper and lithium on Ni/$Al_2O_3$ improved both the conversion and selectivity to 3FCl, but an excessive amount of lithium reduced the conversion as well as the selectivity of 3FCl. However, in the case of Ni/$SiO_2$, the conversion was greatly reduced possibly due to a loss of silica support with high surface area by the reaction of $SiO_2$ with HF. Such a reduction in conversion also can be ascribed to the decrease in active sites, caused by the addition of alkali metal compound, LiOH.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.36D no.1
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• pp.47-56
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• 1999

As the density of logic gates of VLSI chips has rapidly increased, more number of I/O pins has been required. This results in bigger package size and higher packager cost. The package cost is higher than the cost of bare chips for high I/O count VLSI chips. As the density of logic gates increases, the reduction method of the number of I/O pins for a given complexity of logic gates is required. In this paper, we propose the novel I/O interface circuit using CTR (Constant-Transition-Rate) code to reduce 50% of the number of I/O pins. The rising and falling edges of the symbol pulse of CTR codes contain 2-bit digital data, respectively. Since each symbol of the proposed CTR codes contains 4-bit digital data, the symbol rate can be reduced by the factor of 2 compared with the conventional I/O interface circuit. Also, the simultaneous switching noise(SSN) can be reduced because the transition rate is constant and the transition point of the symbols is widely distributed. The channel encoder is implemented only logic circuits and the circuit of the channel decoder is designed using the over-sampling method. The proper operation of the designed I/O interface circuit was verified using. HSPICE simulation with 0.6 m CMOS SPICE parameters. The simulation results indicate that the data transmission rate of the proposed circuit using 0.6 m CMOS technology is more than 200 Mbps/pin. We implemented the proposed circuit using Altera's FPGA and confimed the operation with the data transfer rate of 22.5 Mbps/pin.

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2648-2656
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• 2011

A simple HPLC-DAD method was developed and validated to determine B group vitamin content (thiamine, riboflavin, nicotinamide, pantothenic acid, pyridoxine and folic acid) in supplemented food samples, i.e., infant formula, cereal, low-calorie food, a multi-vitamin pill and a vitamin drink. In this study, the most significant advantages were simultaneous determination of the six B group vitamins in various food matrices and a small number of sample treatment steps that required only an organic solvent, acetonitrile. Moreover, this method prevents reduction of column durability, because the mobile phase does not contain ion-pairing reagents. Analytes were separated on a Develosil RPAQUEOUS $C_{30}$ (4.6 mm ${\times}$ 250 mm, 5 ${\mu}M$ particle size) column with a gradient elution of acetonitrile and 20 mM phosphate buffer (pH 3.0) at a flow rate between 0.8 and 1.0 mL/min. Detection was performed at 275 nm, except for that of pantothenic acid (205 nm). The calibration curves for all six vitamins showed good linearity with correlation coefficients ($r^2$) higher than 0.995. The developed method was validated with respect to linearity, intra- and inter-day accuracy and precision, limit of quantification (LOQ), recovery and stability. The method showed good precision and accuracy, with intra- and inter-assay coefficients of variation less than 15% at all concentrations. The recovery was carried out according to the standard addition procedure, with yields ranging from 89.8 to 104.4%. This method was successfully applied to the determination of vitamin B groups in supplemented food products.

• Archives of Plastic Surgery
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• v.47 no.6
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• pp.583-589
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• 2020

Background Reduction mammoplasty or mastopexy is performed as an additional balancing procedure in patients with large or ptotic breasts who undergo breast-conserving surgery (BCS). Radiation therapy on breasts that have undergone surgery may result in changes in the volume. This study presents a comparative analysis of patients who received post-BCS balancing procedures to determine whether volume changes were larger in breasts that received radiation therapy than on the contralateral side. Methods Thirty-six participants were selected among patients who received BCS using the inverted-T scar technique between September 2012 and July 2017, were followed up for 2 or more years, and had pre-radiation therapy computed tomography images and post-radiation therapy images taken between 12 and 18 months after completion. The average age of the participants was 53.5 years, their average body mass index was 26.62 kg/㎡. Results The pre- and post-radiation therapy volumes of the breasts receiving BCS were 666.08±147.48 mL and 649.33±130.35 mL, respectively. In the contralateral breasts, the volume before radiation therapy was 637.69±145.72 mL, which decreased to 628.14±166.41 mL after therapy. The volume ratio of the affected to the contralateral breasts was 1.05±0.10 before radiation therapy and 1.06±0.12 after radiation therapy. Conclusions The ratio of the volume between the two breasts immediately after surgery and at roughly 18 months postoperatively was not significantly different (P=0.98). For these reasons, we recommend a simultaneous single-stage balancing procedure as a reasonable option for patients who require radiation therapy after BCS without concerns regarding volume change.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6129-6132
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• 2012

Objectives: To evaluate the feasibility and efficacy of simultaneous accelerated radiation therapy (SMART) and concurrent weekly paclitaxel in the treatment of locally advanced nasopharyngeal carcinoma. Methods: Forty-one patients with pathologically confirmed nasopharyngeal carcinoma were treated by SMART with concurrent weekly paclitaxel. Daily fraction doses of 2.5 Gy and 2.0 Gy were prescribed to the gross tumor volume (GTV) and clinical target volume (CTV) to a total dose of 70 Gy and 56 Gy, respectively. Paclitaxel of $45mg/m^2$ was administered concurrently with radiation therapy every week. Adjuvant chemotherapy was given four weeks after the completion of the radiotherapy (RT) if the tumor demonstrated only a partial response (PR). Results: All patients completed the radiotherapy (RT) course. Adjuvant chemotherapy was administered to 12 patients due to PR. The CR (complete remission) rate was 82.9% three months after RT. Thirty-nine (95.1%) patients completed the concurrent weekly chemotherapy with paclitaxel, and two patients skipped their sixth course. Seven patients had a 15% dosage reduction at the fifth and sixth course due to grade 3 mucositis. The median follow-up was 30 (range, 14-42) months. The three-year overall survival (OS), metastases-free survival (MFS), and local control rates were 77.0%, 64.4%, and 97.6%, respectively. No correlation between survival rate and T or N stage was observed. Grade 3 acute mucositis and xerostomia were present in 17.1% and 7.1%, respectively. Conclusion: SMART with concurrent weekly paclitaxel is a potentially effective and toxicity tolerable approach in the treatment of locally advanced NPC.