• Title/Summary/Keyword: Double Split

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Simultaneous two-layer harvesting of scalp split-thickness skin and dermal grafts for acute burns and postburn scar deformities

  • Oh, Suk Joon
    • Archives of Plastic Surgery
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    • v.46 no.6
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    • pp.558-565
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    • 2019
  • Background The scalp, an excellent donor site for thin skin grafts, presents a limited surface but is rich in stem cells. The purpose of this study was to test a double harvesting procedure from the scalp and to evaluate the capacity of the dermal layer. Methods Two layers corresponding to a split-thickness skin graft (SSG) and a split-thickness dermal graft (SDG) were harvested from the scalp using a Zimmer dermatome during the same procedure. Healing of the scalp donor site, reason for recipient site grafting, and the percentage of graft loss were evaluated. Results Fourteen patients, comprising six men and eight women with a mean age of 34.2 years, were treated according to our protocol. The most common reason for a recipient site graft was a postburn scar deformity (10/14 patients). The mean area of scalp SSGs was 151.8 cm2. The mean area of scalp SDGs was 88.2 cm2. The mean healing time of scalp donors was 9.9 days. The only donor complication was a tufted scar deformity. Conclusions Skin defects in the scalp of donors healed faster and led to less scarring than defects at other donor sites. Scalp SDGs needed 10 days for adequate epithelization. The scalp was the best donor site for SSGs and SDGs for burn reconstructive patients.

VEHICLE LONGITUDINAL AND LATERAL STABILITY ENHANCEMENT USING A TCS AND YAW MOTION CONTROLLER

  • Song, J.H.;Kim, H.S.;Kim, B.S.
    • International Journal of Automotive Technology
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    • v.8 no.1
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    • pp.49-57
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    • 2007
  • This paper proposes a traction control system (TCS) that uses a sliding mode wheel slip controller and a PID throttle valve controller. In addition, a yaw motion controller (YMC) is also developed to improve lateral stability using a PID rear wheel steering angle controller. The dynamics of a vehicle and characteristics of the controllers are validated using a proposed full-car model. A driver model is also designed to steer the vehicle during maneuvers on a split ${\mu}$ road and double lane change maneuver. The simulation results show that the proposed full-car model is sufficient to predict vehicle responses accurately. The developed TCS provides improved acceleration performances on uniform slippery roads and split ${\mu}$ roads. When the vehicle is cornering and accelerating with the brake or engine TCS, understeer occurs. An integrated TCS eliminates these problems. The YMC with the integrated TCS improved the lateral stability and controllability of the vehicle.

A study on the Switched Reluctance Motor drive by a New Converter Topology (새로운 컨버터 토폴로지에 의한 스위치드 리럭턴스 모터의 구동에 관한 연구)

  • Kang, Wook;Kim, Hack-Seong;Ryoo, Hong-Je;Won, Chung-Yuen
    • Proceedings of the KIEE Conference
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    • 1994.07a
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    • pp.459-461
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    • 1994
  • This paper proposed a new converter topology improving the split source type converter. In this converter. two switches and six diodes add to the split source type converter. The proposed converter has a performance minimized a negative torqe, putting a phase current off by double impressed voltage 2Vdc. Hence, a new converter results in increase of the average output power and improves converter efficiency in heavy load and high speed. Theoretical prediction is verified by experimental results got with a new proposed converter and 8/6 poles SRM.

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A study on the new converter for the switched reluctance motor drive (스위치드 리럭턴스 전동기 구동을 위한 새로운 컨버터에 관한 연구)

  • Kang, Wook;Won, Chung-Yuen
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.2
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    • pp.217-226
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    • 1996
  • Switched reluctance motor (SRM) drives appear today as viable alternatives to induction and brushless motor drives in a wide range of application such as machine tools, fans, and pumps. This paper deals with a new converter topology which can be used in order converter. The split source type converter consists of minimum switching devices to be used in switched reluctance motor (SRM) drive. In this proposed converter two switches and six diodes are added to split source type converter. The proposed converter has performance minimizes the negative torque, Which puts the phase current off by double impressed voltages. The major advangtage of this converter is the increase of the average output power while improving better converter efficiency in heavy load and high speed than other topologies. The proposed converter system has been implemented using 80C196KB microcontroller and experiments were carried out ot verify the simulation results.

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Power Flow Analysis for Manufacturing of Planetary Gears in an 8-speed Automatic Transmission (II): 4-8 Speeds (8단 자동변속기의 유성기어 가공을 위한 동력 흐름 해석 (2) : 4-8단)

  • Lee, Kyoung-Jin;Kim, Jeong-Min
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.15 no.5
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    • pp.57-65
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    • 2016
  • The power flow of an 8-speed automatic transmission was analyzed using a lever analogy for the manufacturing of planetary gears. From the analysis, we found that the engine power was split between the first and second double-pinion planetary gears (DPPG1 and DPPG2), and was then passed to the DPPG3 for the fourth speed. For the fifth speed, the engine power was split between the DPPG1 and DPPG3. For the speeds 6-8, the engine power was passed only to SPPG2, while the seventh speed contained the power circulation.

Calcium and CN bimodality of RGB stars in Globular clusters with Multiple Populations

  • Lim, Dongwook;Roh, Dong-Goo;Han, Sang-Il;Lee, Young-Wook
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.2
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    • pp.144.1-144.1
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    • 2012
  • A number of recent observations have established that many globular clusters have double or multiple stellar populations. In particular, recent Calcium and Stromgren b & photometry shows a split in the RGB of some of these globular clusters, including M22, NGC 1851, and NGC 288. However, the origin of this split in the RGB is still controversial. In order to confirm the real difference in Calcium abundance between the two RGBs, we have performed low resolution spectroscopy for RGB stars in these globular clusters. The spectral data were obtained from WFCCD/duPont 2.5m telescope in Las Campanas Observatory. We found a significant bimodality of both Calcium and CN abundances in M22 and NGC 1851. NGC 288, however, shows a clear bimodality only in CN abundance.

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Development of a Torsion Joint Yoke for Motor-Driven Power Steering System Using a Double-Action Extrusion Process (더블-액션 압출공정을 적용한 전동조향장치용 토션조인트 요크 개발)

  • Kim, H.M.;Kim, Y.K.;Park, Y.B.
    • Transactions of Materials Processing
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    • v.21 no.8
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    • pp.473-478
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    • 2012
  • The yoke, a component of conventional motor-driven power steering system, often contains welding defects from its manufacturing process. To eliminate these defects, the precision cold forging process has been tried. In this study, the double-action complex forging has been used to manufacture a torsion joint yoke. The backward extrusion proved faster than the forward extrusion in forging of the product. The double-action complex forging process utilized an upper die composed of a punch, a punch guide, a disc spring and a coil spring. The forged material pushes up the punch guide, and then the disc spring and the coil spring balances the backward extrusion force. Consequently, the flow of material was essentially in the forward direction, resulting in a successful forging operation. The forging load of Al 6061-T6 was higher than that of the automotive structural hot rolled plate.

Power comparison for 3×3 split plot factorial design (3×3 분할요인모형의 검정력 비교연구)

  • Choi, Young Hun
    • Journal of the Korean Data and Information Science Society
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    • v.28 no.1
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    • pp.143-152
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    • 2017
  • Restriction of completely randomization within a block can be handled by a split plot factorial design splitted by several plots. $3{\times}3$ split plot factorial design with two fixed main factors and one fixed block shows that powers of the rank transformed statistic for testing whole plot factorial effect and split plot factorial effect are superior to those of the parametric statistic when existing effect size is small or the remaining effect size is relatively smaller than the testing factorial effect size. Powers of the rank transformed statistic show relatively high level for exponential and double exponential distributions, whereas powers of the parametric and rank transformed statistic maintain similar level for normal and uniform distributions. Powers of the parametric and rank transformed statistic with two fixed main factors and one random block are respectively lower than those with all fixed factors. Powers of the parametric andrank transformed statistic for testing split plot factorial effect with two fixed main factors and one random block are slightly lower than those for testing whole plot factorial effect, but powers of the rank transformed statistic show comparative advantage over those of the parametric statistic.

Improvement of efficiency in Multi-layer IPMSM using Response Surface Methodology (반응 표면법을 이용한 Multi-layer 매입형 영구자석 동기정동기의 효율 향상)

  • Fang, Liang;Kwon, Soon-O;Lee, Sang-Ho;Zhang, Peng;Hong, Jung-Pyo
    • Proceedings of the KIEE Conference
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    • 2006.07b
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    • pp.777-778
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    • 2006
  • This paper deals with the optimum rotor design approach about the multi-layer design of the buried magnets in an Interior Permanent Magnet Synchronous Motor (IPMSM), on the efficiency improvement by using Response Surface Methodology (RSM). In the multi-layer design of the prototype 15kw IPMSM, the constant amount of buried PM is split from the single-layer into double-layer design for improving the efficiency characteristics. The optimum double-layer rotor structure is built with the help of RSM analysis. The improvement of IPMSM efficiency is verified by the Finite Element Method (FEM) results comparison with the prototype single-layer IPMSM.

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SOFT TISSUE CHANGES AFTER DOUBLE JAW ROTATION SURGERY IN SKELETAL CLASS III MALOCCLUSION (골격성 III 급 부정 교합자에서 양악 회전 수술 후 연조직 변화에 대한 연구)

  • Jeong, Mi-Hyang;Choi, Jeong-Ho;Kim, Byuong-Ho;Kim, Seong-Gon;Nahm, Dong-Seok
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.32 no.6
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    • pp.559-565
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    • 2006
  • The aim of this study was to evaluate the amount and interrelationship of the soft and hard tissue changes after simultaneous maxillary clockwise rotation and mandibular setback surgery in skeletal class III malocclusion. The sample comprised of 16 adult patients who had anteroposterior skeletal discrepancy. These patients had received presurgical orthodontic treatment and surgical treatment which consisted of Le fort I Osteotomy and bilateral saggital split ramus osteotomy. The presurgical (T1) and postsurgical (T2) lateral cephalograms were evaluated. The computerized statistical analysis was carried out with SPSS/PC program. The results demonstrated a decrease in the vertical dimension in the soft and hard tissue. The nasolabial angle was increased and the mentolabial angle was decreased. The results showed also many statistically significant correlations(p<0.05). The lower lip closely followed the skeletal movement of the B- point in the horizontal plane. The double jaw rotation surgery can afford a good solution to solve the problems of class III malocclusion cases.