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This study investigated the effect of pre-oxidation on the high-temperature oxidation behavior of Fe-Cr-Al powder porous metal. Using the powder metallurgy process, Fe-Cr-Al powder porous metals with and without pre-oxidation were manufactured. 24-hour TGA tests were conducted at three different temperatures: 900°C, 1000°C, and 1100°C. The high temperature oxidation results showed that pre-oxidized powder porous metal had even higher levels of oxidation resistance compared to that of porous metal without pre-oxidation regardless of the oxidation temperature. The weight gain of pre-oxidized porous metal (0.123%) was lowest at oxidation temperature of 900°C. In contrast, the weight gain of porous metals significantly increased at 1100°C. In the porous metals 900°C and 1000°C oxidized specimen, oxides such as Al2O3and Cr2O3were mainly observed. Porous metals oxidation specimen at 1100°C also revealed the presence of Fe-based oxides in large quantities in addition to the oxides formed at lower temperature.

Gas/liquid two-phase ejector is a device without moving parts, in which liquid is used to drivegas of a low-pressure source. In this paper, the hydrodynamic characteristics of a vertical down type two-phase ejector were studied using an air-water loop system. Entrained air flow rates were measured withinlet and outlet pressures of the ejector with varying water flow rate. Homogeneous bubbly flows in thedischarge pipe were confirmed by the high speed flow visualization method. Quantitative measurementsof void fraction were made using a newly developed fiber optic probe system. Key Words:Two-Phase Flow (이상유동), Ejector (이젝터), Flow Visualization (유동가시화), Fiber opticprobe(광섬유 탐침), Void fraction(기포분율) 1. 서론 기체-액체 이상유동 이젝터는 설치가 간편하고, 안정적인 작동 특성으로 인하여 여러 가지 경우의 화학공정및 플랜트에서 중요하게 사용되는 장치중 하나이다. 이상유동 이젝터는 액체를 주유동으로 분사시키고, 이젝터의 목 부분에서 형성되는 음압으로 기체를 흡입하여혼합과정과 이송과정을 동시에 실현시킨다 (1, 2) . 이젝터에 관한 선행연구로 Witte(1962)는 다중 오리피스와 상당히 긴 혼합튜브를 이용하여 이젝터의 등온압축효율이 40%까지 개선될 수 있음을 보고하였다. 이젝터의 성능을 평가하기 위한 최소한의 측정값은 1차유체 및 2차 유체의 체적 유량과 세 지점의 압력 즉 이젝터 전단 압력 P

This paper describes a study of conventional electrical rig and simulated application of Flywheel Energy Storage system on the power system of the offshore plants with dynamic positioning system with the following aims: improve fuel consumption on engines, prevent blackout and mitigate voltage sags due to pulsed load and fault. Fuel consumption has been analyzed for the generators of the typical drilling rigs compared with the power plant with Flywheel Storage Unit which has an important aid in avoiding power interruption during DP (Dynamic Positioning) operation. The FES (Fly wheel Energy storage System) releases energy very quickly and efficiently to ensure continuity of the power supply to essential consumers such as auxiliary machinery and thrusters upon main power failure. It will run until the standby diesel generator can start and supply the electric power to the facilities to keep the vessel in correct position under DP operation. The proposed backup method to utilize the quick and large energy storage Flywheel system can be optimized in any power system design on offshore plant.

This study investigated the high temperature oxidation of Ni–Fe–Cr–Al porous metal. Two types of open porous metals with pore sizes of 30 and 40 PPI were used. For 24-h, the isothermal oxidation TGA tests were conducted at three different temperatures of 900, 1000, and 1100 °C. The oxidation resistance of porous metal decreased with decreasing pore size. Porous metals mainly created oxides such as Al2O3, Cr2O3, NiAl2O4, and NiCr2O4. The porous metal represented increasingly faster dwindling of Al and Cr content and easy progress to internal oxidation, comparing to the oxidation of bulk metal.

Nongrowing adult patients with skeletal open bite have been considered among the most difficult to treat. This case report describes the surgical-orthodontic treatment of a blind 20-year-old woman who presented with skeletal class II malocclusion with vertical maxillary excess, anterior open bite, and transverse maxillary deficiency.After the transverse maxillary deficiency was corrected with miniscrew-assisted rapid palatal expansion, Le Fort I osteotomy with anterior segmental osteotomy and bilateral sagittal split ramus osteotomy with advancement genioplasty were used to correct the vertical maxillary excess and the anterior open bite. The patient's facial appearance was markedly improved, and she achieved a functional and stable occlusion after these treatments.This case report demonstrates the efficiency of miniscrew-assisted rapid palatal expansion for a patient with transverse maxillary deficiency and the benefit of a team approach using effective orthodontic mechanics in orthognathic surgery to correct a severe dentofacial deformity.

The majority of turfgrass composition of golf courses are zoysiagrass, and mingle with cool-season turfgrasses have been increased. As result of mingling the species, invading problem has been raised. In this study, 50 golf courses nationwide were surveyed of grass composition and invading problem with hetero-species of turfgrasses. Among the courses, 47 golf courses have invading problem with more than one species at least. The invading problem has been issued most of golf course in nationwide. Thirty-seven courses composited with zoysiagrass; at 25 courses showed creeping bentgrass invading and at 33 courses were invaded by kentucky bluegrass. Among 47 kentucky bluegrass composition courses, 43 courses had creeping bentgrass invading problem. Invading problem within the grass species (creeping bentgrass in zoysiagrass, kentucky bluegrass in zoysiagrass, creeping bentgrass in kentucky bluegrass); 14, 12, and 21 courses were detected single species, two species, and three species invading problem, respectively.

In this study, we attempted to control invaded hetero-species turfgrass in golf courses with herbicides. Asulam sodium SP and trifloxysulfuron-sodium WG (to control creeping bentgrass in zoysiagrass), trifloxysulfuron-sodium WG (to control kentucky bluegrass in zoysiagrass), and mesotrione SC (to control creeping bentgrass in kentucky bluegrass) were selected as efficient herbicides. To creeping bentgrass, asulam sodium SP and trifloxysulfuron-sodium WG until 70 days after application (DAA), mesotrione SC until 230 DAA and to kentucky bluegrass trifloxysulfuron-sodium WG until 110 DAA; the applications showed 90% herbicidal effect. At 4 X recommended application dose, asulam sodium SP, trifloxysulfuronsodium WG (to zoysiagrass) and mesotrione (to kentucky bluegrass) showed insignificant harmful effect. With recommended dose, asulam sodium SP showed 80% control effect of creeping bentgrass in zoysiagrass until 40 DAA and trifloxysulfuron-sodium WG demonstrated 85% control efficiency until 30 DAA. Trifloxysulfuron-sodium WG controlled 85% of kentucky bluegrass in zoysiagrass until 40 DAA. Mesotrione SC with recommended dose showed 95% control efficiency to creeping bentgrass in kentucky bluegrass.

Objective To evaluate transverse skeletal and dental changes, including those in the buccolingual dental axis, between patients with skeletal Class III malocclusion and facial asymmetry after bilateral intraoral vertical ramus osteotomy with and without presurgical orthodontic treatment. Methods This retrospective study included 29 patients with skeletal Class III malocclusion and facial asymmetry including menton deviation > 4 mm from the midsagittal plane. To evaluate changes in transverse skeletal and dental variables (i.e., buccolingual inclination of the upper and lower canines and first molars), the data for 16 patients who underwent conventional orthognathic surgery (CS) were compared with those for 13 patients who underwent preorthodontic orthognathic surgery (POGS), using three-dimensional computed tomography at initial examination, 1 month before surgery, and at 7 days and 1 year after surgery. Results The 1-year postsurgical examination revealed no significant changes in the postoperative transverse dental axis in the CS group. In the POGS group, the upper first molar inclined lingually on both sides (deviated side, -1.8° ± 2.8°, p = 0.044; nondeviated side, -3.7° ± 3.3°, p = 0.001) and the lower canine inclined lingually on the nondeviated side (4.0° ± 5.4°, p = 0.022) during postsurgical orthodontic treatment. There were no significant differences in the skeletal and dental variables between the two groups at 1 year after surgery. Conclusions POGS may be a clinically acceptable alternative to CS as a treatment to achieve stable transverse axes of the dentition in both arches in patients with skeletal Class III malocclusion and facial asymmetry.

Background/purpose Few studies have evaluated craniofacial growth in boys and girls with idiopathic short stature (ISS) during growth hormone (GH) treatment. The aim of this study was to evaluate the effect of GH treatment on craniofacial growth in children with ISS, compared with those with growth hormone deficiency (GHD). Methods This study included 36 children (mean age, 11.3 ± 1.8 years) who were treated with GH consecutively. Lateral cephalograms were analyzed before and 2 years after start of GH treatment. Results There were no significant differences in age and sex between ISS and GHD groups and the reference group from semilongitudinal study (10 boys and 8 girls from each group). Before treatment, girls with ISS showed a skeletal Class II facial profile compared with the GHD and reference groups (p = 0.003). During GH treatment, the amount of maxillary length increased beyond norm in the ISS and GHD groups in boys (p = 0.035) > 3 standard deviation score (SDS). Meanwhile, mandibular ramus height (p = 0.001), corpus length, and total mandibular length (p = 0.007 for both) increased more in girls with ISS than in girls with GHD. Lower and total anterior facial heights increased more in girls with ISS than in girls with GHD (p = 0.021 and p = 0.007, respectively), > 7–11 SDS. Conclusion GH should be administered carefully when treating girls with ISS, because GH treatment has great effects on vertical overgrowth of the mandible and can result in longer face.

The aim of this retrospective cohort study was to evaluate the postoperative stability of sagittal split ramus osteotomy (SSRO) and intraoral vertical ramus osteotomy (IVRO) in pre-orthodontic orthognathic surgery (POGS) for skeletal Class III malocclusion. Thirty-seven patients (SSRO, n = 18; IVRO, n = 19) who underwent bimaxillary surgery were divided into two groups according to the type of surgery. During the postoperative period, there were no significant differences in anterior and superior movements of the mandible at point B between the two groups, but occlusal plane angle of the SSRO group significantly decreased more than that of the IVRO group (P = 0.003). Only the SSRO group showed a linear relationship between the amount of postoperative horizontal and vertical movements of the mandible (R(2) = 0.254; P = 0.033), indicating that the amount of postoperative upward movement of the mandible increased as the amount of postoperative forward movement increased (r = -0.504; P = 0.033). The mandible after SSRO in POGS rotated counterclockwise due to rigid fixation between two segments, whereas the mandible after IVRO without rigid fixation in POGS moved mainly in a superior direction. These differences must be considered before surgery to ensure postsurgical stability for patients with mandibular prognathism.

Here, we evaluated time-dependent changes in the effects of ultraviolet (UV) and nonthermal atmospheric pressure plasma (NTAPPJ) on the biological activity of titanium compared with that of untreated titanium. Grade IV machined surface titanium discs (12-mm diameter) were used immediately and stored up to 28 days after 15-min UV or 10-min NTAPPJ treatment. Changes of surface characteristics over time were evaluated using scanning electron microscopy, surface profiling, contact angle analysis, X-ray photoelectron spectroscopy, and surface zeta-potential. Changes in biological activity over time were as determined by analysing bovine serum albumin adsorption, MC3T3-E1 early adhesion and morphometry, and alkaline phosphatase (ALP) activity between groups. We found no differences in the effects of treatment on titanium between UV or NTAPPJ over time; both treatments resulted in changes from negatively charged hydrophobic (bioinert) to positively charged hydrophilic (bioactive) surfaces, allowing enhancement of albumin adsorption, osteoblastic cell attachment, and cytoskeleton development. Although this effect may not be prolonged for promotion of cell adhesion until 4 weeks, the effects were sufficient to maintain ALP activity after 7 days of incubation. This positive effect of UV and NTAPPJ treatment can enhance the biological activity of titanium over time.

OBJECTIVE: To evaluate the structural stability of anodic oxidation treatment of miniscrews during a self-drilling procedure and an initial loading period. MATERIALS AND METHODS: Eight orthodontic miniscrews with a machined surface and an anodic oxidized surface were placed in the mandible of two beagle dogs. With all miniscrews, an orthodontic force was applied immediately after placement and was continued for 12 weeks. After beagle dogs were sacrificed, the miniscrews were carefully removed from decalcified bone fragments. Miniscrews were evaluated by comparing and quantitatively analyzing changes in surface roughness of unused and used miniscrews (machined surface vs anodic oxidized surface) utilizing both scanning electron microscopy (SEM) and atomic force microscopy (AFM). RESULTS: SEM revealed that only a thread edge close to the tip of the used anodic oxidized miniscrew became smooth by smearing, compared with the unused anodic oxidized miniscrew. No definite changes were observed in the thread valleys of the two groups after placement. AFM measurements demonstrated that all surface roughness parameters of thread edges of the used anodic oxidized miniscrews were significantly reduced compared with the unused anodic oxidized miniscrew (P < .05). A middle thread edge of the used anodic miniscrew surface was rougher than the unused and used machined surface miniscrews (P < .05). CONCLUSION: Anodic oxidized miniscrews had improved surface characteristics compared with machined surface miniscrews, even if the surface texture was changed by the self-drilling procedure and during the initial loading period.

Eu3+-doped (Y,Gd)NbO4 phosphor was synthesized by solid-state reaction for possible application in cold cathode fluorescent lamps.A broad absorption band with peak maximum at 272 nm was observed which was due to the charge transfer between Eu3+ ions and neighboring oxygen anions.A deep red emission at the peak wavelength of 612 nm was observed which could be attributed to the 5D0→7F2 transition in Eu3+ ions.The highest luminance for Y1x-yGdyNbO4:Eux3+ under 254 nm excitation was achieved at Eu3+ concentration of 18 mol.％(x=0.18) and Gd3+ concentration of 8.2 mol.％ (v=0.082).The luminance of Y0.738Gd0.082NbO4:Eu3+0.18 was higher than that of a typical commercial phosphor Y2O3:Eu3+ and the CIE chromaticity coordinate was (0.6490,0.3506),which was deeper than that of Y2O3:Eu3+.The particle size of the synthesized phosphors was controlled by the NaCl flux and particle size as high as 8μm with uniform size distribution of particles was obtained.

The aim of this retrospective cohort study was to investigate the factors contributing to mandibular relapse after intraoral vertical ramus osteotomy (IVRO) while controlling for possible confounders. Forty-seven patients who underwent bimaxillary surgery were divided into three groups according to the direction of horizontal mandibular relapse: a stable group (group S), a posterior relapse group (group P), and an anterior relapse group (group A). Lateral cephalograms were analysed 1 month before and at 7 days and 12 months after surgery. One month before surgery, the pogonion in group A was positioned about 13 mm more anteriorly than in group P (P

In this study, cast bulk specimens and powder sintered specimens were produced from a Fe-22% Cr-5.8% Al alloy, which has been drawing industrial attention for its outstanding high-thermal and oxidation resistance as well as for its applicability as a filter and support material. The high-temperature oxidation behaviors of the specimens were compared and analyzed. Two types of specimens were subjected to 24-hour isothermal oxidation (temperatures of 900 °C, 1000 °C, and 1100 °C and a gas atmosphere of 79% N2+21% O2) to understand their high-temperature oxidation properties. The oxidized specimens were examined via X-ray, SEM, FE-SEM, and EPMA for microstructure and oxide analyses. The results of the oxidation tests showed that both bulk and powder-sintered specimens gained weight as temperature increased, with the powder sintered specimens gaining far more weight than the bulk specimens. As the temperature increased, the bulk specimens showed sequential formation of Al2O3, Cr2O3, and Fe3O4 oxide layers. The stable Al2O3 on the surface of the bulk specimens was found to play a role in arresting the rapid growth of oxide layers. In the powder-sintered specimens, however, the internal diffusion of O2 easily took place along the powder interfaces. As a result, far more oxidation occurred in the powder-sintered specimens than in the bulk specimens. Cracks and disintegration of the oxide layers were also found to have occurred as the temperature increased. The high-temperature oxidation mechanisms of bulk and powder-sintered materials in relation to temperature increase are further discussed.

The herbicidal action of clove oil on cucumber seedlings was characterized under light and dark conditions. Paraquat showed herbicidal activity only under the light condition, whereas the clove oil displayed herbicidal activity in both the light and the dark condition. Specifically, wilting and water content reduction progressed rapidly under both the light and the dark condition 1 h after the clove oil treatment, whereas the paraquat damage occurred only under the light condition 5 h after treatment. The malondialdehyde concentration increased more with the clove oil treatment than with the paraquat treatment under the light and dark conditions. The superoxide dismutase (SOD) activity was stimulated, but the catalase activity decreased in the clove oil treatment. In contrast, both the SOD and catalase activity decreased in the paraquat treatment. These results suggest that clove oil exerts herbicidal effects through a mechanism that is different from that of paraquat.

【This study investigated the high temperature oxidation behavior of Ni-22.4%Fe-22%Cr-6%Al (wt.%) porous metal. Two types of open porous metals with different pore sizes of 30 PPI and 40 PPI (pore per inch) were used. A 24-hour TGA test was conducted at three different temperatures of $900^{\circ}C$ , $1000^{\circ}C$ and $1100^{\circ}C$ . The results of the BET analysis revealed that the specific surface area increased as the pore size decreased from 30 PPI to 40 PPI. The oxidation resistance of porous metal decreased with decreasing pore size. As the temperature increased, the oxidation weight gain of the porous metal also increased. Porous metals mainly created oxides such as $Al_2O_3$ , $Cr_2O_3$ , $NiAl_2O_4$ , and $NiCr_2O_4$ . In the 40 PPI porous metal with small pore size and larger specific surface area, the depletion of stabilizing elements such as Al and Cr occurred more quickly during oxidation compared to the 30 PPI porous metal. Ni-Fe-Cr-Al porous metal's high-temperature oxidation micro-mechanism was also discussed.】

This study investigated the effect of the pore size of Ni-22.4%Fe-22%Cr-6%Al porous metal on its hightemperature oxidation. Two types of open porous metals with pore sizes of 800 μm and 580 μm were used. A 24-hour isothermal oxidation test was conducted at three different temperatures of 900 °C, 1000 °C, and 1100 °C under a 79% N2 + 21% O2 atmosphere. The results of the BET analysis revealed that the specific surface area increased as the pore size decreased from 800 μm to 580 μm. The high-temperature oxidation results showed that porous metals exhibited far lower levels of oxidation resistance compared with bulk metals, and that the oxidation resistance of porous metals decreased with a decreasing pore size. According to the microstructural observations of the oxide layers, the 900 °C and 1000 °C oxidation layer contained Ni, Cr, and Al oxides mainly on the strut. The 800 μm porous metal strut exhibited similar oxidation behavior at 1100 °C to that found at lower temperatures. In contrast, the 580 μm porous metal strut was found to consist of Ni and Fe oxides in the upper layer and Ni, Cr, and Al oxides in the lower layer, representing a low oxidation resistance. For powders affixed to the strut inside the porous metal, a different oxide-forming behavior from that of the strut was observed. In addition, the Ni-Fe-Cr-Al porous metal high-temperature oxidation microscopic mechanism is also discussed.

This study investigated the high temperature oxidation behavior of Fe-22%Cr-5.8%Al alloy and the oxidation kinetics of the alloy were discussed. Bulk samples were prepared by VAM (vacuum arc melting) and hot forging. High temperature oxidation testes were isothermally conducted up to 100 hours in 79%+21% environment at three different temperatures (, , ). The weight gain was measured after oxidation according to oxidation time (2, 4, 6, 8, 10, 15, 20, 25, 30, 60, 80, 100 hours). The weight gain significantly increased with increasing oxidation temperature. As the temperature increased, the oxidized samples showed sequential formation of , Cr-rich oxide, Fe-rich oxide. The activation energy of high temperature oxidation was obtained as 306.63 KJ/mol. were developed on the surface in the early stage of oxidation, representing protective role of oxidation. However, Fe-based and Cr-based oxides leaded to breakaway of oxide layer, thus resulted in the significant increase of additional oxidation.

This study attempted to investigate the high temperature tensile deformation behaviour of new Al-1%Mg-1.1%Si0.8%CoNi heat resistant aluminium alloy. New aluminium alloy strengthened by Co-Ni based phase was manufactured by using powder ball milling and continuous casting, based on the alloy design & preliminary test. High temperature tensile tests were conducted at various temperatures from 25�� to 450�� . OM, SEM, EPMA, XRD, FIB and HR-TEM equipments were used to analyse microstructure, phases, and fracture surface. Microstructure of the new alloy mainly consisted of Al matrix and Co-Ni based phases (1~8 Πm). The Co-Ni based phase was analyzed and confirmed as (Ni, Co)3Al having incoherent interface with matrix. In high temperature tensile results, the new aluminium alloy didn’t show significant decrease (19.6%) of strength with increasing temperature (450�E ), suggesting totally different behaviour with conventional A319 alloy (87.0% decrease of T.S.). Fractography observation results of new alloy represented the ductile fracture mode with dimples. Voids were mainly initiated at Co-Ni based strengthening phases. It was apparently observed that the strengthening effect of the (Ni, Co)3Al could be still maintained at high temperature of 450�� . The deformation mechanism of this alloy was also discussed. © 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of ICM11

We have investigated electrical characteristics of laser-crystallized polycrystalline silicon thin film transistors (poly-Si TFTs) under various stresses such as bias, temperature, light illumination. The threshold voltage of short channel TFT (LCH=1.5μm) was significantly shifted to negative direction due to bias temperature stress (ΔVTH = -3.75V) compared with that of long channel TFT (ΔVTH = -0.32V) at 100{degree sign}C. We have also investigated the effects of light illumination on the laser-crystallized poly-Si TFT. In order to improve the reliability of laser-crystallized poly-Si TFT, a novel multiple-channel structure was proposed and fabricated without any additional processes. In addition, in order to enhance the electric characteristics and stability of alternating magnetic-field-enhanced rapid thermal annealing (AMFERTA) poly-Si TFTs, we have employed the NH3 plasma pretreatment prior to crystallization process. The NH3 plasma pretreatment process could effectively improve the reliability of AMFERTA poly-Si TFTs.

This study was conducted to investigate the phytotoxic effects of 19 essential oils on seed germination and initial growth of rapeseed (Brassica napus L.). We found that anise, cinnamon, citronella, clove, geranium, lemongrass, mustard and pine oils completely inhibited germination of rapeseed at 100× dilute solution. Based on the inhibition rates of rapeseed emergence and initial growth, three essential oils (cinnamon, clove, and geranium) were selected as potential bio-herbicides. Under pre-emergence applications of cinnamon, clove, and geranium oils at 90 kg ai ha -1 , rates of rapeseed emergence were 7.1, 25.0, and 3.6% and its initial growth were 22.0, 9.9 and 11.0%, respectively.

Previous diagnosing methods based on agglutination have a limitation in view of emergency and point-of-care diagnoses due to the requirement of large scale equipments and much agglutination time. In this paper, we propose a low cost microfluidic lab-on-a-chip for more efficient detection of agglutination. In the present lab-on-a-chip, two inlet microwells, flow guiding microchannels, chaotic micromixer and reaction microwell are fully integrated. Mold inserts for the lab-on-a-chip were manufactured by UV photolithography and nickel electroplating process. The complete lab-on-a-chip was realized by the microinjection molding of cyclic olefin copolymer and the subsequent thermal bonding. The improved serpentine laminating micromixer, developed by our group, integrated in the lab-on-a-chip showed the high-level of chaotic mixing, thereby enabling us to get a reliable mixing of sample and reagent. The performance of the fabricated lab-on-a-chip was demonstrated by agglutination experiments with simulated bloods of 10 μl and simulated sera of 10 μl. The results of agglutination inside the reaction microwell were clearly read by means of the level of light transmission. The present microfluidic lab-on-a-chip could be widely applied to various clinical diagnostics based on agglutination tests.

High quality nanocrystalline silicon (nc-Si) film was deposited by inductively coupled plasma chemical vapor deposition (ICP-CVD) without substrate RF bias at 350 °C. The nc-Si with a dense crystalline structure of the columnar type grew from the bottom to the top of the nc-Si film. A troublesome incubation layer did not exist at the bottom of the fabricated nc-Si film. A grain size of 40 nm was measured by using a SEM image. When a RF bias of 100 and 200 W was applied to the substrate to induce ion bombardment on the substrate, the crystalline structure and grains were not observed and a-Si deposition became dominant. The transition from nc-Si deposition into a-Si deposition can be attributed to ion bombardment which prevents nucleation and crystal growth at the surface of deposition. This shows that the reduction of ion bombardment can be a key factor to fabricate high quality nc-Si film. By using ICP-CVD with no substrate RF bias, ion bombardment can be reduced, while the density of plasma is kept high, so that high quality nc-Si can be fabricated due to the enhancement of crystalline growth on the surface.

The hysteresis phenomenon of both a-Si and poly-Si TFT has been studied in order to investigate the hystersis phenomenon effect on residual image of AMOLED display. The transfer characteristics of both a-Si:H TFT and poly-Si TFT were varied according to the gate voltage sweep direction due to the different initial interface trapped charges in the gate insulator. The threshold voltage in a-Si:H TFT was altered by 0.23V due to hysteresis of device according to gate sweep direction while that in poly-Si TFT was varied by 0.21V due to the different gate insulator. In order to suppress hystersis effect on OLED current error we proposed and fabricated a new pixel circuit. By applying the reset voltage in pixel circuit, the data voltage sweep direction could be fixed and hysteresis effect on OLED current error was successfully suppressed. We showed that the OLED current error was successfully suppressed by experiment.

Highly stable voltage programmed a-Si:H TFT pixel circuit for AMOLED, which employs both Vth-compensation and negative bias annealing, is proposed and fabricated. Experimental results, after 60 hours electrical stress at elevated temperature (60°C) show that the OLED current stability in the proposed pixel is considerably improved compared with a conventional 2-TFT pixel, Vth-compensated pixel, and negative bias annealed pixel, respectively. The proposed pixel can reduce the degradation of a-Si:H TFT by employing negative bias annealing store Vth of a-Si:H TFT so that highly stable and uniform a-Si:H TFT backplane for AMOLED. Our proposed pixel may be suitable for highly stable AMOLED employing the a-Si:H TFT.

Purpose Few studies have evaluated the outcomes of intraoral vertical ramus osteotomy (IVRO) for the correction of skeletal Class III malocclusion with an anterior open bite and the potential for postoperative relapse. Therefore, this study evaluated the stability of outcomes of IVRO for mandibular prognathism with and without an anterior open bite. Material and Methods This retrospective cohort study included consecutive patients with skeletal Class III malocclusion with (AOB group) and without (NAOB group) an anterior open bite who underwent IVRO at Yonsei Dental Hospital (Seoul, Korea). Lateral cephalograms were analyzed for predictor (open bite, yes or no) and outcome (horizontal and vertical relapse in the mandible) variables before and 7 days, 1 year, and 2 years after surgery. Other variables included the patients' demographic characteristics. Data were analyzed using independent t tests, repeated measures analysis of variance, Pearson correlation coefficients, and multiple linear regression analysis. Results The 2 groups (n = 15 each) were matched for baseline demographic characteristics. During the 2-year postoperative period, anterior and superior mandibular movements were observed in the NAOB group, whereas posterior and superior movements were observed in the AOB group. However, there were no meaningful intergroup differences in horizontal and vertical relapses of the mandible at all time points, although the amount of postoperative inferior relapse increased with a decrease in the amount of initial overbite. Conclusions IVRO for the correction of skeletal Class III malocclusion resulted in good postoperative stability over time, regardless of the presence of a preoperative open bite, although the amount of postoperative inferior relapse showed a weak negative correlation with the initial overbite. Thus, IVRO can be a clinically acceptable treatment for skeletal Class III malocclusion with an anterior open bite.

This case report describes the beneficial effects of the interdisciplinary treatment of an adult patient with severe skeletal periodontal problems. A 30-year-old female patient presented with anterior open bite, gummy smile, and facial asymmetry. The patient had chronic generalized severe periodontitis with pathologic maxillary anterior teeth migration and mild intellectual disability. Treatment included 6 months of periodontal treatment, followed by presurgical orthodontic treatment, a Le Fort I osteotomy with anterior segmental osteotomy, a bilateral sagittal split ramus osteotomy, and postsurgical orthodontic treatment. After treatment completion, the patient exhibited functional and aesthetic improvements. Her periodontal condition improved and was maintained after the treatment. Here, we demonstrate a successful treatment outcome in a complicated case following a systematic interdisciplinary approach performed with the correct diagnosis and treatment planning.

Objective: To evaluate the differences in maxillomandibular transverse measurements at either the crown or the estimated center of resistance (CR), and to compare values between normal occlusion and Class III malocclusion groups. Methods: Dental casts and computed tomography (CT) data from 30 individuals with normal occlusion and 30 with skeletal Class III malocclusions were evaluated. Using the casts, dental arch widths (DAWs) were measured from the cusp tips, and basal arch widths (BAWs-cast) were measured as the distance between the points at the mucogingival junction adjacent to the respective cusp tips. The BAWs determined from CT (BAWs-CT) images were measured from the estimated CRs of the teeth. Results: None of the DAW measurements or maxillomandibular DAW differences showed statistically significant intergroup differences. In contrast, the maxillary BAWs-CT and BAWs-cast were lesser in the Class III malocclusion group than in the normal occlusion group. The mandibular BAWs-CT were significantly greater in the Class III malocclusion group than in the normal occlusion group. Moreover, the maxillomandibular BAW differences on both CT and cast showed significant intergroup differences in all transverse measurements. Conclusions: The maxillomandibular DAW differences showed no significant intergroup differences. In contrast, the maxillomandibular BAW differences on both CT and cast showed significant intergroup differences in all transverse measurements. The maxillomandibular BAW differences at the estimated CRs, measured using CT or casts, can reveal underlying transverse maxillary basal arch deficiencies in patients with skeletal Class III malocclusions.

The aim of this study was to evaluate the effect of malocclusion severity on oral health-related quality of life and food intake ability in adult patients, controlling for sex, age, and the type of dental clinic visited.The sample consisted of 472 Korean patients (156 male, 316 female) with a mean age of 21.1 (SD, 8.6) years in a dental hospital and a private clinic. The correlations between the Korean version of the Oral Health Impact Profile-14 (OHIP-14K), subjective food intake ability (FIA) for 5 key foods, and Index of Orthodontic Treatment Need-Dental Health Component (IOTN-DHC) were investigated.The mean IOTN-DHC and OHIP-14K scores were significantly higher for the dental hospital patients than for the private clinic patients (IOTN-DHC, P 0.001; OHIP-14K, P 0.05). Malocclusion severity was significantly higher in male than in female subjects (P 0.001). Older patients perceived their oral health-related quality of life more negatively than did the teens (P 0.001). As the severity of the malocclusion increased, oral health-related quality of life and masticatory function worsened (OHIP-14K, P 0.001; FIA, P 0.05).As the severity of the malocclusion and the age of the patients increased, oral health-related quality of life and masticatory function relatively deteriorated. This finding provides evidence that severe malocclusions are associated with lower quality of life and less masticatory efficiency in older patients.

Proton irradiation technology was used for improvement of switching characteristics of the PT-IGBT. Proton irradiation was carried out at 5.56 MeV energy with doze from the back side of the wafer. The I-V, breakdown voltage, and turn-off delay time of the device were analyzed and compared with those of un-irradiated device and e-beam irradiated device which was conventional method for minority carrier lifetime reduction. For proton irradiated device, the breakdown voltage and the on-state voltage were 733 V and 1.85 V which were originally 749 V and 1.25 V, respectively. The turn-off time has been reduced to 170 ns, which was originally for the un-irradiated device. The proton irradiated device was superior to e-beam irradiated device for the breakdown voltage and the on-state voltage which were 698 V and 1.95 V, respectively, nevertheless turn-off time of proton irradiated device was reduced to about 60 % compared to that of the e-beam irradiated device.

Agglutination is one of the most commonly employed reactions in clinical diagnosis. In this paper, we have designed and fabricated nickel mold insert for injection molding of a microfluidic lab-on-a-chip for the purpose of the efficient detection of agglutination. In the presented microfluidic lab-on-a-chip, two inlets for sample blood and reagent, flow guiding microchannels, improved serpentine laminating micromixer(ISLM) and reaction microwells are fully integrated. The ISLM, recently developed by our group, can highly improve mixing of the sample blood and reagent in the microchannel, thereby enhancing reaction of agglutinogens and agglutinins. The reaction microwell was designed to contain large volume of about of the mixture of sample blood and reagent. The result of agglutination in the reaction microwell could be determined by means of the level of the light transmission. To achieve the cost-effectiveness, the microfluidic lab-on-a-chip was realized by the injection molding of COC(cyclic olefin copolymer) and thermal bonding of two injection molded COC substrates. To define microfeatures in the microfluidic lab-on-a-chip precisely, the nickel mold inserts of lab-on-a-chip for the injection molding were fabricated by combining the UV photolithography with a negative photoresist SU-8 and the nickel electroplating process. The microfluidic lab-on-a-chip developed in this study could be applied to various clinical diagnosis based on agglutination.

We have designed and fabricated poly-Si TFTs employing various counter-doped lateral body terminals (LBT) which suppress a kink current and improve the reliability under the various electrical stresses. Our experimental results show that the TFT with a LBT structure connected near the drain region was more effective to suppress the kink current and to reduce the leakage current. The suppression of the kink effect employing LBT structure can be attributed to the decrease of E-field at the drain junction due to the potential redistribution in the channel of the TFT by the counter doped LBT and the collecting holes, which have been generated by impact ionization at the drain.

Aminofunctional organosilanes, such as 3-aminopropyltriethoxysilane (APTES), have been widely utilized as adhesion promoters, and have also been found to have the ability to prevent dewetting of polymer thin films from substrates. The APTES molecule contains an active terminal amino group that can hydrogen bond with the multiple hydroxylated head groups in itself and hydroxyl groups on a substrate, thus forming cyclic structures and a complex loose network at ambient conditions. Upon heating, the hydrogen bond can be broken, allowing more silanol groups to condense with each other and form siloxane linkages, hence tightening the three-dimensional network. When a polymer thin film is in contact with the APTES layer during the thermal process, the polymer chains can diffuse/penetrate into the APTES network while the network is being tightened by the additional crosslinking. The penetrated and subsequently anchored chains could help to stabilize the thin film on the substrate. This hypothesis was verified by dewetting studies of thin films of polystyrene (PS), having molecular weights above and below the entanglement molecular weight ( M e ), from APTES and control surfaces when the systems were subjected to various treatments. Dewetting suppression was observed for PS/APTES that was thermally treated at ∼80 °C or 120 °C prior to the annealing of the thin film at higher temperatures. Much stronger suppression was noticed for PS having a molecular weight higher than M e . When PS thin films were deposited onto a precured APTES network, no dewetting suppression was observed.

The effects from cervical facet joint injections in those patients who have been complaining cervical zygapophyseal joint pain were compared. The patients were diagnosed originally as myofascial pain syndrome (MPS), cervical herniated nucleus pulposus (HNP), and whiplash-associated disorders (WAD). Patients with the zygapophyseal joints pain of C5-6 and C6-7 were classified by their pain origin as MPS, HNP, and WAD. All patients had been undergone cervical zygapophyseal joints injections with the mixture of lidocaine and triamcinolone unilaterally or bilaterally through the posterior approach under C-arm imaging guide. The therapeutic effects were compared with reduction of numeric rating scale (NRS) of pain before and immediately after blockade and symptom-free periods in each group after 12 months. Symptom durations before injections were 16.1+/-9.6, 4.6+/-1.9 and 4.1+/-1.1 months in each MPS, HNP, and WAD groups. The reductions of NRS immediately after the blockade among the three groups were not different. However, the symptom-free duration after blockade lasted longer in the HNP group than the other two groups. In patients with cervical zygapophyseal pain syndromes, the analgesic effect from cervical facet joint blocks lasted longer in cervical HNP than MPS or WAD.

We designed and fabricated highly reliable multiple-channel indium-gallium-zinc oxide (IGZO) thin-film transistors (TFTs) without any additional fabrication processes. We also investigated the geometric factors of the multiple-channel structure that influence the reliability of the IGZO TFTs in high saturation mode, such as the spacing and width of the subchannels. The proposed device exhibited superior reliability(ΔVTH

Anticholinesterase does not allow adequate reversal of the deep neuromuscular blockade (NMB) achieved using high doses of relaxants. A 71-year-old female patient (weight 70 kg, height 169 cm) was scheduled for a transurethral resection of a bladder tumor under general anesthesia. We administered rocuronium 30 mg (0.43 mg/kg) for tracheal intubation due to an estimated short surgical time. During the operation, an additional rocuronium 10 mg was injected. The surgical procedure ended abruptly 10 minutes after receiving the last dose of rocuronium. At the end of surgery, the patient received pyridostigmine as a reversal. However, residual NMB persisted, and neuromuscular monitoring did not show the expected degree of recovery. Sugammadex 2 mg/kg was used, and the patient experienced complete reversal from NMB in just 2 min.

Gradient surfaces are widely employed in biological studies for protein adsorption and cell attachment and growth. They also offer great potential in the areas of fluid flow and combinatorial experimental design for obtaining material properties and behaviors. Gradient surfaces are created with organosilanes by using the diffusion techniques proposed by Ewling and modified by Chaudhury. However, these techniques have limitations. They either generate a significant amount of organic waste or require well-controlled deposition conditions. In this paper, we propose a fast, convenient, reproducible, and inexpensive method that generates gradient surfaces with minimum waste generation. Particularly, we have adopted Whitesides's contact-printing technique to achieve a gradient by gradually varying the contact time over the contacted area using octadecyltrichlorosilane. Elastomeric stamps with different geometries and various radii of curvature are used to generate gradient surfaces at both millimeter and microm...

We investigated the effect of the deposition temperature on the electrical performance of SiOx passivation layers for amorphous indium-gallium-zinc-oxide thin-film transistors (a-IGZO TFTs). Compared to the time-of-flight secondary ion mass spectroscopy depth profile of the IGZO film with a SiOx passivation layer deposited at low temperature (150oC ), that with the SiOx film formed at 300oC exhibited the significant migration of metal ions from the IGZO film into the SiOx passivation layer. These results were attributed to the high-energy ion bombardment on the IGZO channel layer. In order to suppress the interdiffusion of In, Ga, and Zn atoms between the IGZO and passivation layers, we proposed double SiOx passivation using different substrate temperatures. It combines the merits of low-temperature (150oC) and high-temperature (300oC) passivations and compensates for their individual weaknesses. We confirmed the enhanced electrical characteristics and improved reliability of the IGZO TFTs compared to those of the conventional device.

Objective This retrospective, cross-sectional study aimed to establish reference data for normal crown and root lengths and the root-crown ratios (R/C ratios) for the mature maxillary and mandibular incisors in a Korean population by using cone-beam computed tomography (CBCT). Methods We included 672 Korean patients (141 men and 531 women; mean age, 27.2 ± 7.7 years) who underwent CBCT examinations during various dental treatments. Crown and root lengths and the R/C ratios of the maxillary and mandibular incisors were measured using CBCT data, which were analyzed to detect significant differences between demographic factors as well as sagittal and vertical skeletal or occlusal relationships. Results Teeth of the same type in each half-arch were symmetrical. The mean R/C ratios varied from 1.1 to 1.2 for the maxillary incisors and from 1.3 to 1.4 for the mandibular incisors. Crown and root lengths were greater in men than in women, regardless of tooth type. Root lengths and R/C ratios for the mandibular incisors were significantly greater in patients with skeletal Class II malocclusion or an excessive overjet than in the other patients. The R/C ratios for the mandibular incisors were lower in patients with an open bite than in those with a normal or deep bite. Moreover, the R/C ratios for the mandibular incisors increased with age. Conclusions The data obtained in our study can serve as reference values for crown and root lengths and the R/C ratios for the maxillary and mandibular incisors in the Korean population.

Although ventricular tachycardia/fibrillation (VT/VF) develops suddenly with catastrophic results, its prediction is limited. We tested the fibrillation number (FibN) for potential predictor of VT/VF using clinical data of implantable cardioverter-defibrillator (ICD) patients after validating the number by computational modeling.For clinical application of FibN, we used electrocardiography and echocardiography data: QRS width, QTc, and left ventricular (LV) end-systolic dimension (FibNVT/VF1) or LV end-diastolic dimension (FibNVT/VF2). We compared the maintenance duration of VT/VF for various FibN values using computational modeling, and tested FibNVT/VF in 142 patients with ICD for secondary prevention and 426 patients in age-sex matched control group (81.9% male, 56.1 ± 12.3 years old).1. Computational results showed a positive correlation between VT/VF maintenance duration and FibN (R = 0.82, p 0.001). 2. FibNVT/VFs were significantly higher in patients with ICD than in control (both FibNVT/VF1 and FibNVT/VF2, p 0.001). 3. Within ICD group, FibNVT/VF values were higher in patients with cardiomyopathy than those without (both FibNVT/VF1 and FibNVT/VF2, p 0.001). 4. During 50 ± 39 months follow-up period, the frequency of appropriate ICD therapy was higher in the high FibNVT/VF group (FibNVT/VF1, p = 0.001; FibNVT/VF2, p = 0.002). Both FibNVT/VF1 (HR 2.51, 95%CI 1.48-4.24, p = 0.001) and FibNVT/VF2 (HR 2.11, 95%CI 1.25-3.55, p = 0.005) were independently associated with appropriate ICD therapy in multi-variate analyses.FibNVT/VF, a parameter based on wavelength and heart size, correlates well with maintenance of VT/VF in computational modeling, and may have predictive value for VT/VF events in patients with ICD for secondary prevention.

To reduce a large amount of mandibular setback and to prevent pharyngeal airway space narrowing when correcting a severe anteroposterior skeletal discrepancy, a mandibular step osteotomy is often combined with 2-stage orthognathic surgery. This case report describes a successful 2-stage orthognathic treatment combined with a mandibular step osteotomy. A 20-year-old man had severe mandibular protrusion, facial asymmetry, and macroglossia. Phase 1 surgery included the mandibular step osteotomy and a partial glossectomy; then we performed phase 2 surgery with a 2-piece LeFort I segmental osteotomy and a bilateral intraoral vertical ramus osteotomy to correct the patient's mandibular protrusion and facial asymmetry. The total treatment period was 30 months, and the final result was improvement of the patient's facial appearance.

Distraction osteogenesis is an alternative treatment option for patients with facial asymmetry and mandibular hypoplasia. New bone is formed between bone segment surfaces that are gradually separated by incremental traction. The purpose of this article is to report the treatment of a 22-year-old man with hemifacial microsomia, facial asymmetry, and a skeletal Class II profile. The patient's left mandibular ramus was lengthened with distraction osteogenesis, and miniscrew-assisted rapid palatal expansion was used to correct the maxillary transverse deficiency. Postoperative orthodontic treatment achieved tooth alignment and closure of the posterior open bite. The total treatment period was 27 months. These therapeutic treatments improved the patient's facial appearance.