• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.5
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• pp.347-356
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• 2001

The issues that influence the packaging of high-speed LiNbO$_{3}$ modulators are discussed, and packaging approaches that result in only minor degradation of the modulator's RF performance are described. The primary problems dealt in this paper, associated with high-speed device packaging, are fallen into the following five categories: die features, pigtailing, suppression of RF package resonance, RF launcher approach, termination approach. By considering factors to influence the modulator performance in packaging, a LiNbO$_{3}$ intensity modulator was fabricated and packaged to have S21 better than -3㏈ upto 10㎓ and S11 below -l5㏈ upto 18㎓.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.38
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• pp.46.1-46.7
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• 2016

Background: Osteoradionecrosis is the most dreadful complication after head and neck irradiation. Orocutaneous fistula makes patients difficult to eat food. Fibular free flap is the choice of the flap for mandibular reconstruction. Osteocutaneous flap can reconstruct both hard and soft tissues simultaneously. This study was to investigate the success rate and results of the free fibular flap for osteoradionecrosis of the mandible and which side of the flap should be harvested for better reconstruction. Methods: A total of eight consecutive patients who underwent fibula reconstruction due to jaw necrosis from March 2008 to December 2015 were included in this study. Patients were classified according to stages, primary sites, radiation dose, survival, and quality of life. Results: Five male and three female patients underwent operation. The mean age of the patients was 60.1 years old. Two male patients died of recurred disease of oral squamous cell carcinoma. The mean dose of radiation was 70.5 Gy. All fibular free flaps were survived. Five patients could eat normal diet after operation; however, three patients could eat only soft diet due to loss of teeth. Five patients reported no change of speech after operation, two reported worse speech ability, and one patient reported improved speech after operation. The ipsilateral side of the fibular flap was used when intraoral soft tissue defect with proximal side of the vascular pedicle is required. The contralateral side of the fibular flap was used when extraoral skin defect with proximal side of the vascular pedicle is required. Conclusions: Osteonecrosis of the jaw is hard to treat because of poor healing process and lack of vascularity. Free fibular flap is the choice of the surgery for jaw bone reconstruction and soft tissue fistula repair. The design and selection of the right or left fibular is dependent on the available vascular pedicle and soft tissue defect sites.

• Journal of Korean Foot and Ankle Society
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• v.8 no.1
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• pp.101-106
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• 2004

Purpose: To determine the efficacy of the SDBBA (Subtalar distraction bone block arthrodesis) procedure on patients with late complication of intra-articular calcaneal fractures including subtalar joint arthritis and anterior ankle impingement syndrome. Materials and Methods: Five cases in which the SDBBA procedure was implemented were followed for more than one year. All five patients were male with an average age of 56. Clinically, the American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot score and the pain score were assessed. Radiographically, the talocalcaneal height and the talar inclination angle were determined. Results: All five patients achieved subtalar joint fusion. The average pre-operative AOFAS score was 22.8 scores (range, 8-32 scores). At last follow-up, these scores improved to an average of 72.4 scores (range, 64-82 scores). The average pre-operative pain score was 8.2 scores (range, 7-10 scores). At last follow-up, these scores improved to an average of 13.2 (range, 12-15 scores). The average pre-operative talocalcaneal height was 72.8 mm (range, 70-77 mm), average post-operative talocalcaneal height improved to 79.8 mm (range, 78-84 mm). At final follow-up, these measurement was slightly decreased to average 78.6 mm (range, 74-83 mm). The average pre-operative talar inclination angle was 13.2 degrees (range, 12-15 degrees), average post-operative talar inclination angle improvedto 19.2 degrees (range, 15-24 degrees). At final follow-up, these measurement was slightly decreased to average 18.6 degrees (range, 12-24 degrees). Four patients achieved successful outcomes. One patient developed a wound infection with subsequent sural neuropathy as well as collapse of the bone graft. Conclusion: This study shows that the SDBBA procedure successfully restores the talocalcaneal height and tibio-talar relationship. This procedure is useful in surgically managed patients with talo-calcaneal height loss and anterior ankle impingement syndrome due to the late complications of calcaneal intra-articular fractures.

• The Journal of Korean Academy of Prosthodontics
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• v.55 no.2
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• pp.171-179
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• 2017

Severely worn dentition is frequently multifactorial. It is crucial that the etiology of excessive wear be determined, but accurately diagnosing the factors responsible for tooth wear is often confusing. Before initiating the treatment of these cases, meticulous examination and determining vertical dimension are essential. A 69-year-old male patient had the chief complaint that he has worn dentition and functional and esthetic discomfort. Based on model analysis and diagnostic wax up, new vertical dimension had been determined. Provisional restorations were cemented and after 5 months permanent prostheses were fabricated. This case reports a satisfactory functional and esthetic clinical outcome achieved by restoring the vertical dimension.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.7
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• pp.664-672
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• 2009

In this paper we propose an on-glass antenna which consists of conducting dual center striplines and multi-loaded striplines. Multi-loaded striplines and dual center lines were employed for achieving a broad matching bandwidth and improving a vertical radiation gain, respectively. The detail design parameters were determined using the Pareto genetic algorithm with an full wave EM simulator. The optimized design was built and installed on a commercial vehicle, and the antenna performances such as the return loss and the radiation gain were measured in a semi-anechoic chamber. The measurement results showed the matching bandwidth($S_{11}$<-3 dB) of about 49 % in the T-DMB frequency band, the vertical gain of about -3 dBi along the bore-sight direction, and the average gain of about -10 dBi along the azimuth direction.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.9
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• pp.1566-1572
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• 2004

Effects of azodicarbonamide (ADA) were investigated on the rheological properties of flour dough by measuring farinogram, amylogram and extensogram based on the amount of ADA added. Quality characteristics of the bread made with the ADA added dough were also evaluated by measuring dough volume, moisture content, pH, proofed time, baking loss and textural characteristics. The farinogram showed that water absorption, stability and elasticity of the dough with ADA were higher than those without ADA. However, its absorption time and weakness decreased compared to the dough without ADA. Through the amylogram, it was found that gelatinization temperature and maximum viscosity increased, but temperature of maximum viscosity reduced in the dough with ADA. The extensogram showed that the area and resistance of the dough increased slightly but extensibility decreased drastically after fermentation, resulting in the ratio of resistance and extensibility (R/E) of the dough with ADA was lower than those without ADA. The bread prepared with the dough containing ADA after freezing up to 12 weeks showed higher pH and specific loaf volume but lower moisture content, second proof time and resistance than those without ADA.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.23 no.5
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• pp.439-446
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• 2020

Purpose: The evidence for an association between inflammatory bowel disease (IBD) and obesity is conflicting. Therefore, we set out to review the body mass index (BMI) at presentation of IBD to understand if the rise of the obesity rate in the general population, lead to an increase of obesity in patients with IBD at the time of diagnosis. Methods: Retrospective review of all patients with IBD seen at Children's Hospital and Medical Center from January 1st 2010 to December 31st 2014. From the initial visit and endoscopy, we obtained: age; sex; BMI; disease phenotype; disease severity. Results: We had a total of 95 patients, 35 patients were excluded due to incomplete data or referral being made after diagnosis was made. 28 were males and 32 were females, Age range was 2-17 years. A 37 had Crohn's disease, 19 ulcerative colitis, and 4 indeterminate colitis. Disease severity in 19 cases was mild, 29 moderate and 12 severe. BMI distribution was as follows-obese (5.0%), overweight (6.7%), normal weight (65.0%), mild malnutrition (8.3%), moderate malnutrition (15.0%), severe malnutrition (1.7%). Conclusion: Our data is consistent with other series. Showing most children had a normal BMI, regardless of disease severity or phenotypes. One confounding factor is the possibility of delay in referral to GI. This could mean some obese children may fall in the normal BMI range at the time of diagnosis due to ongoing weight loss. Future studies should include prospective cohort studies, comparing incidence of IBD in obese and non-obese patients, severity at presentation, duration of symptoms, and clinical outcomes.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.319-319
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• 2013

Even though the fabrication methods of metal oxide based thin film capacitor have been well established such as RF sputtering, Sol-gel, metal organic chemical vapor deposition (MOCVD), ion beam assisted deposition (IBAD) and pulsed laser deposition (PLD), an applicable capacitor of printed circuit board (PCB) has not realized yet by these methods. Barium Strontium Titanate (BST) and other high-k ceramic oxides are important materials used in integrated passive devices, multi-chip modules (MCM), high-density interconnect, and chip-scale packaging. Thin film multi-layer technology is strongly demanded for having high capacitance (120 nF/$mm^2$). In this study, we suggest novel multi-layer thin film capacitor design and fabrication technology utilized by plasma assisted deposition and photolithography processes. Ba0.6Sr0.4TiO3 (BST) was used for the dielectric material since it has high dielectric constant and low dielectric loss. 5-layered BST and Pt thin films with multi-layer sandwich structures were formed on Pt/Ti/$SiO_2$/Si substrate by RF-magnetron sputtering and DC-sputtering. Pt electrodes and BST layers were patterned to reveal internal electrodes by photolithography. SiO2 passivation layer was deposited by plasma-enhanced chemical vapor deposition (PE-CVD). The passivation layer plays an important role to prevent short connection between the electrodes. It was patterned to create holes for the connection between internal electrodes and external electrodes by reactive-ion etching (RIE). External contact pads were formed by Pt electrodes. The microstructure and dielectric characteristics of the capacitors were investigated by scanning electron microscopy (SEM) and impedance analyzer, respectively. In conclusion, the 0402 sized thin film multi-layer capacitors have been demonstrated, which have capacitance of 10 nF. They are expected to be used for decoupling purpose and have been fabricated with high yield.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.398-398
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• 2013

The electronic properties and the local structure of tantalum oxide thin film with variation of oxygen flow rate ranging from 9.5 to 16 sccm (standard cubic centimeters per minute) have been investigated by X-ray photoelectron spectroscopy (XPS), Reflection Electron Energy Loss Spectroscopy (REELS), and X-ray absorption spectroscopy (XAS). The XPS results show that the Ta4f spectrum for all films consist of the strong spin-orbit doublet $Ta4f_{7/2}$ and $Ta4f_{5/2}$ with splitting of 1.9 eV. The oxygen flow rate of the film results in the appearance of new features in the Ta4f at binding energies of 23.2 eV, 24.4 eV, 25.8, and 27.3 eV, these peaks attribute to $Ta^{1+}$, $Ta^{2+}$, $Ta^{4+}$/$Ta^{2+}$, and $Ta^{5+}$, respectively. Thus, the presence of non-stoichiometric state from tantalum oxide ($TaO_x$) thin films could be generated by the oxygen vacancies. The REELS spectra suggest the decrease of band gap for tantalum oxide thin films with increasing the oxygen flow rate. The absorption coefficient ${\mu}$ and its fine structure were extracted from the fluorescence mode of extended X-ray absorption fine structure (EXAFS) spectra. In addition, bond distances (r), coordination numbers (N) and Debye-Waller factors (${\sigma}^2$) each film were determined by a detailed of EXAFS data analysis. EXAFS spectrapresent both the increase of coordination number of the first Ta-O shell and a considerable reduction of the Ta-O bond distance with the increase of oxygen flow rate.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.8
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• pp.336-342
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• 2018

Noise reduction is an important issue in auxiliary power unit(APU) of tracking equipments for using military. In this study, we designed and tested reduction methods of structure borne noise and airborne source noise at the auxiliary power unit. From the bench test results, it is found that the effect of noise reduction is about 22 dB(A) if the silencer is redesigned, which is the rescue structure. However, the influence of noise reduction by air is insufficient. In addition, it is confirmed that the effect of noise reduction is excellent when structure borne noise reduction is applied to the vehicle. We expected that the test results of this study are used as basic data to reduce the noise of other tracking equipment developed later.