• 한국전자파학회논문지
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• 제20권11호
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• pp.1145-1160
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• 2009

본 논문에서는 soft surface를 이용하여 IEEE 802.11a/b 대역에서 10 dBi 이상의 이득과 유사한 모양의 복사 패턴과 이득을 가지며, 동작하는 신호 중계 장치용 안테나를 제안한다. 제안한 안테나의 크기는 $50{\times}56.5{\times}5.5\;mm^3$이고, soft surface를 포함한 접지면의 크기는 $175.0{\times}154.4\;mm^2$이다. 안테나는 동축 케이블을 이용하여 급전하였으며, 두께가 0.508 mm이고 비유전율이 3.38인 RO4003 기판 위에 설계하였다. 전산 모의 실험 결과, VSWR<2 기준으로 2.388~2.493 GHz와 5.561~6.051 GHB의 대역폭을 가지며, 각 대역의 중심 주파수에서의 이득은 10.63 dBi와 10.33 dBi이다.

• 대한치과보철학회지
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• 제52권1호
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• pp.27-33
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• 2014

연구 목적: 본 연구는 임플란트 보철물과 인접치 사이의 식편압입을 호소하는 환자를 대상으로 각종 임상 자료를 분석하여 식편압입의 임상적 발현 양상을 알아보고자 하였다. 연구 재료 및 방법: 식편압입을 주소로 내원한 보철물 장착이 완료된 임플란트 환자 51명을 대상으로 설문조사와 구강검사를 시행하고 방사선 사진과 모형을 채득하여 식편압입과 관련이 있는 요소를 분석한 결과 다음과 같은 결과를 얻었다. 결과: 1. 식편압입은 하악(39.2%)보다 상악(60.7%)에서 많이 나타났다. 2. 식편압입은 자연치아가 임플란트 보철물의 원심 부위(13.7%)에 있는 경우보다 근심 부위(86.2%)에 있는 경우에 많이 나타났다. 3. 식편압입이 나타난 임플란트 보철물과 그 인접치 사이의 접촉점은 긴밀하지 않은 경우(94.2%)가 대부분이었다. 결론: 임플란트 보철물과 인접치 사이에 식편압입이 일어나지 않기 위해서는 임플란트 보철물과 인접치아가 적절한 긴밀도를 가지고 있어야 하겠다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제37권
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• pp.38.1-38.6
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• 2015

Background: The posterior movement of mandible was known as the main cause of the changes in the pharyngeal airway space (PAS) and the postoperative obstructive sleep apnea (OSA). The purpose of this study was to know the changes of PAS and position of hyoid bone. Methods: Lateral cephalographies of 13 patients who had undergone sagittal split ramus osteotomy (SSRO) setback surgery were taken preoperatively (T1), postoperatively within 2 months (T2), and follow-up after 6 months or more (T3). On the basis of F-H plane, diameters of nasopharynx, oropharynx, and hypopharynx were measured. The movements of the soft palate, tongue, and hyoid bone were also measured. Results: The amount of mandible setback was $7.5{\pm}3.8mm$. In the measurements of PAS, there was a statistically significant decrease of $2.8{\pm}2.5mm$ in nasopharynx (P < 0.01), and $1.7{\pm}2.4mm$ in oropharynx (P < 0.01) were observed after surgery. The hypopharynx decreased $1.0{\pm}2.1mm$ after surgery and continuously decreased $1.0{\pm}2.8mm$ at follow-up. The changes in hyoid bone position showed the posterior movement only after surgery and posteroinferior movement at follow-up. Conclusions: The PAS such as nasopharynx, oropharynx, and hypopharynx showed relatively high correlation with the amount of mandibular setback. The change of resistance in upper airway may be important for the prevention of OSA after mandibular setback surgery.

• 대한치과교정학회지
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• 제22권1호
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• pp.89-107
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• 1992

The purpose of this study was to investigate the difference between normal and malocclusion subjects in Temporomandibular joint. This study was based on the 44 subjects with normal occlusion, 30 subjects with Class II malocclusion, 30 subjects with Class III malocclusion before treatment. After submental vertex view analysis, each subject was given the TMJ Tomogram in centric relation and centric occlusion and the Cephalogram was taken with Quint Sectograph. The TMJ spaces were measured and analyzed statistically. Following results were obtained. 1. When centric relation was compared to centric occlusion, The condyles were positioned more posteriorly and superiorly in centric relation position of the normal occlusion group and the class II malocclusion group. In the Class III malocclusion group. There was no significant difference in the condylar position between centric occlusion and centric relation. 2. The condyles of the Class III malocclusion group were positioned more superiorly than the normal occlusion group and the Class II malocclusion group. 3. In the correlation between articular eminence posterior slope angle and lingual slope angle of the upper anterior central incisor, there was significant correlation in the normal occlusion group. But no significant correlation was found in the malocclusion group. 4. The mean value of the horizontal angulation of condylar head to the transear rod axis plane was $20.32^{\circ}{\pm}8.12^{\circ}$ in the normal occlusion group, $25.08^{\circ}{\pm}4.83^{\circ}$ in the class II malocclusion group, $14.68^{\circ}{\pm}4.08^{\circ}$ in the class III malocclusion group.

• 치과방사선
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• 제23권1호
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• pp.103-114
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• 1993

The purpose of this study was to determine whether any difference existed in craniofacial morphology between parents of children with cleft lip and/or palate and parents of children without cleft lip and/or palate as well as the characteristics of craniofacial morphology in parents of children with cleft lip and/or palate. Thirty three measurements of the various regions of cranium and face were obtained from lateral cephalometric radiograms in parents of 28 children with cleft lip and palate, 18 children with cleft lip, and 22 children with cleft palate. There were 28 couples and 40 single parents in this sample. There were 92 individuals including 41 males and 51 females. The measurements were compared with those in control subjects, including 40 adult males and 40 adult females, who had no history of craniofacial abnormalities. The total sample was compared for the sex independently. The obtained results were as follows. 1. In the cranium, both parents of cleft children had significantly shorter posterior cranial base length(S-Ba). 2. In the upper face, a significantly shorter anteroposterior length of maxilla(A'-Ptm'), particularly in the anterior region (A'-K), anterior facial depth(A-SBaL), posterior facia! height(Ptm'-SNL) and relation of subnasale to the cranial base (∠BaN'Sn) were noted in fathers of cleft children. But, all measurements were not found to be significantly different between experimental group and control group in all mothers. 3. In the lower face, both parents of cleft children showed a significantly greater Y axis angle(∠NSGn) and ramal plane angle(∠SNL-RP) in fathers of cleft children. Thus both patents showed a posteriorly rotation of mandible. The thickness of the lower lip(B-B') was significantly thicker in fathers of cleft children. 4. In the facial profile, a significantly shorter posterior facial height(S-Go) and greater angle of soft tissue facial convexity (∠BaN'Pog') were noted in the fathers of cleft children. But, all measurements were not found to be significantly different between experimental group and control group in all mothers.

• 한국작물학회지
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• 제42권3호
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• pp.344-351
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• 1997

The experiment was conducted to examine the varietal variation in gelatinization of rice flour and adaptability to rice bread processing, and the interrelation among the relevant properties. IR 44 showed the lowest temperature of gelatinization onset(T$_{o}$ ) and the highest gelatinization enthalphy(ㅿH) measured by differential scanning calorimetry (DSC). The following lower T$_{o}$ was found with the order of Suweon 230＜Pusa-33-30＜T(N) 1, Daeribbyeo 1 and the next higher ㅿ.H was followed by the order of Pusa-33-30＞Suweon 230. IRAT 177 revealed the highest temperature of gelatinization onset and conclusion(T$_{c}$) and the following higher T$_{c}$ was found with the order of Pusa-33-30＞AC 27＞Nonganbyeo. The varietal range of T$_{o}$ and T$_{c}$ was 50.0~72.5$^{\circ}C$ and 70.2~87.4$^{\circ}C$, respectively. The rice materials tested can be classified by scatter diagram on the plane of upper two principal components contracted from DSC thermogram and various characteristics relevant to processing and sensory preference of rice bread by principal component analysis. AC27, Suweonjo and IR 44 among high-amylose rices showed better suitability to rice bread processing. The temperatures of gelatinization peak and conclusion of rice flour checked by DSC were significantly negatively associated with springiness of rice bread. The most properties relevant to processing and sensory preference of rice bread such as hardness, moistness, springiness, cohesiveness, specific loaf volume and distribution or size of air cell revealed the close correlation between each other.other.

• Archives of Plastic Surgery
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• 제34권3호
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• pp.342-345
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• 2007

Purpose: A common side effect of the scalp reduction is a creation of a 'slot' with the hair growing in the opposite directions away from the scar. Overcoming the unnatural appearance of the slot has been a vexing problem in the scalp reduction surgery. None of the conventional corrective surgical techniques provides a complete and satisfactory aesthetic result. The Frechet flap is a triple transposition flap used for the correction of the slot defect secondary to scalp reduction surgery, seldom needing further scar revision. The Frechet technique provides a solution to the problem of the central slot concealment that is unattainable by other means, such as; Z-plasty and mini-graft. Methods: Authors applied the Frechet technique to Asian patients who had undergone scalp reduction and operated on 4 patients from March, 2000 to January, 2001. Average follow-up period was 13 months. Patients with long scars passing through the temporoparietoccipital zone were excluded. All the undermining was performed in the subgaleal plane, reaching the upper auricular sulcus and stopping just above the nuchal ridge. Results: None of the patients experienced infection, hematoma, nor any permanent hair loss. Transient telogen effluvium at the distal end of flap 2 and 3 was noticeable in one case. Conclusion: In conclusion, the results are aesthetically satisfactory without any significant complications.

• Archives of Plastic Surgery
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• 제44권4호
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• pp.332-336
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• 2017

Background Little is known concerning hair diameter variation within the safe donor area for hair transplantation surgery. Thicker or thinner hair may be needed, depending on the recipient area, hairline design, and the purpose of surgery. Methods Twenty-seven patients (7 men and 20 women; mean age, 28 years; range, 20-47 years) were included in this study. The midoccipital point was used as the reference point on the horizontal plane at the upper border of the helical rim. The target area width was 15 cm (7.5 cm to the right and left of the reference point) and the height was 8 cm (2 cm above and 6 cm below the reference point). The study area was divided horizontally into 3 5-cm sections (A, B, C) and vertically into 4 2-cm sections (1-4), creating a total of 12 zones. Ten anagen hairs were randomly obtained from each zone and their diameters were measured. Results Hair diameter in the 4 vertical sections varied significantly, gradually decreasing from sections 1 (superior) to 4 (inferior) in all 3 horizontal sections (A, B, and C). Conclusions Our results suggest that sections 1 and 2 of the occipital safe donor area would be useful for obtaining thicker hair, such as in procedures to treat male- and female-pattern hair loss, whereas hair from zones 3 and 4 could be useful for transplantation surgery requiring thinner hair, such as eyebrows, eyelashes, and female hairline correction. Our results may be clinically valuable for planning hair transplant surgery and choosing the optimal donor region.

• Progress in Superconductivity
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• 제3권1호
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• pp.23-27
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• 2001

We have investigated the mixed-state magnetoresistance of high quality c-axis-oriented MgB2 thin film for magnetic field from 0.5 T to 5.0 T, applied normal to ab-plane. The temperature dependence of magnetoresistance was well described by vortex glass and fluctuation theories for different temperature regimes. We observed glassy exponent of v(z-1)~3 and upper critical field of $H_{c2}$(0)~35 T, which is consistent with previous data obtained from direct $H_{c2}$(0) measurements. Interestingly, the thermally activated flux flow region was observed to be very narrow, suggesting that the pinning strength of this compound is very strong. This finding is closely related to the recent reports that the bulk pinning is dominant in $MgB_2$and the critical current density of $MgB_2$ thin film is very high, comparable to that of cuprate superconductor. The present results further suggest that $MgB_2$is beneficial to technical applications.ons.

• 대한기계학회논문집A
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• 제35권7호
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• pp.785-790
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• 2011

본 연구에서는 인체의 하지부를 다물체 시스템으로 모델링하여 무릎관절에 걸리는 구속력의 불확실성을 추정하였다. 일반적으로 근육의 기계적인 특성은 Hill-type muscle model 이 사용되며 여기에 적용되는 인체의 특성과 해부학적인 데이터는 지난 십 수년 동안 크게 발전되었다. 그러나 정확하게 그것들을 안다는 것은 불가능하며 개인마다 다른점을 고려해야 할 필요가 있다. 본 논문에서는 Hill-type muscle model 과 함께 인체의 해부학적인 데이터를 통계 방법론을 이용하여 무릎 관절에 걸리는 구속력의 불확실성을 추정하였다. 초기 앉아있는 자세에서 일어서는 과정에서 작용하는 구속력을 추정하였으며 이때 인체 하지 근육의 특성을 musculoskeleton-actuator 를 이용하여 해석하였다.