• Bulletin of the Korean Chemical Society
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• 제30권11호
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• pp.2675-2679
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• 2009

This paper reports the example of headspace mulberry paper bag micro solid phase extraction (HS-MPB-$\mu$-SPE) as a new sampling method for the determination of volatile flavor composition of coriander seeds. Adsorption efficiencies between two configurations of mulberry paper bag were compared, and several parameters affecting the HS-MPB-$\mu$-SPE were investigated and optimized. The optimized technique uses an adsorbent (Tenax TA, 0.1 mg) contained in a mulberry paper bag of front configuration where fine surface was outside, and minimal amount of organic solvent (0.6 mL). Linalool and $\gamma$-terpinene were found as abundant flavor compounds from coriander seeds. The limit of detection (LOD) and the limit of quantitation (LOQ) for linalool of major flavor in coriander seeds were 10.3 ng/mL and 34.4 ng/mL, respectively. The proposed method showed good reproducibility and good recovery. The HS-MPB-$\mu$-SPE is very simple to use, inexpensive, requires small sample amounts and solvent consumption. Because the solvent for extraction is reduced to only a very small volume, there is minimal waste or exposure to toxic organic solvent and no further concentration step.

• Archives of Plastic Surgery
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• 제34권1호
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• pp.105-110
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• 2007

Purpose: The major drawback of submuscular augmentation of the ptotic breast is a "double-bubble" deformity. If a traditional mastopexy is added to correct the ptosis, there would be additional scars. This article describes simultaneous periareolar mastopexy with dual plane or subfascial breast augmentations. Methods: A series of 81 patients with grade I or II ptosis underwent the procedure from 1999 to 2005. Out of these, dual plane augmentation was done in 71 cases and subfascial plane in 10. After periareolar skin excision, an incision is made perpendicularly down to the fascia of pectoralis. At the lower pole, all breast implants are inserted into the subfascial plane. In case of upper pole thickness of above 20 mm, we inserted the implant into the subfascial plane, whereas below 20 mm, we inserted that into the submuscular plane. Results: No major complications were noted and patients' satisfactory score was high. This technique avoids the "double-bubble" deformity and leaves a minimal periareolar scar. Conclusion: Simultaneous periareolar mastopexy/breast augmentation is useful for correction of the ptotic breast, increasing the volume of breast and providing the natural breast shape with minimal scars. We consider that subfascial plane augmentation with periareolar mastopexy to be an alternative for cases with breast upper pole thickness of at least above 20 mm.

• 소성∙가공
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• 제33권4호
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• pp.248-254
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• 2024

The triply periodic minimal surface (TPMS) structure is characterized by a high surface-to-volume (S/V) ratio and the separated internal structure for flow. Combining the different TPMS structures can provide unique flow and strength characteristics. This paper investigates the effects of dimension, density and arrangement of the unit cell of the TPMS on contact and flow areas of combined TPMS structures. Several representative TPMS structures, including primitive, gyroid and diamond structures, are adopted to design gradient and heterogeneous types TPMS structures. The estimation method of contact and flow areas using an image processing technique is proposed. Python software is used to predict contact and flow area. The influence of the combination method of TPMS on contact and flow areas in the contact surface of combined TPMS structures with different shapes is investigated. Based on the results of the investigation, an appropriate combination method of TPMS structures is discussed.

• 대한치과교정학회지
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• 제53권6호
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• pp.358-364
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• 2023

Objective: This study aimed to three-dimensionally evaluate the pharyngeal airway space (PAS) of patients with anterior open bite (AOB) by using cone-beam computed tomography (CBCT) and compare the findings with those obtained in individuals with normal occlusion. Methods: The open bite group (OBG, n = 25) consisted of patients with an anterior overbite of -3 mm or less, while the control group (n = 25) consisted of age- and sex-matched individuals with an anterior overbite of 1-3 mm, Angle Class I malocclusion (1° ≤ point A-nasion-point B angle ≤ 4°), and a normodivergent profile (22° ≤ Frankfort mandibular plane angle ≤ 28°). After the CBCT data were reconstructed into a three-dimensional image, the PAS was segmented into four parts, and the volume of each part was measured. Pharyngeal airway length (PAL) and the area and transverse width of the part showing minimal constriction were also measured. Pearson's correlation analysis was used to evaluate the correlation between changes in the PAS and the amount of anterior overbite. Results: The OBG showed a significantly narrower airway space in the nasopharyngeal, hypopharyngeal, and total airway volumes. The OBG also showed a significantly smaller area and transverse width of the part with minimal constriction. The OBG showed a significantly longer PAL, but there was no correlation between the amount of anterior overbite and the changes in PAS. Conclusions: The PAS was associated with AOB. Patients with AOB had a narrower PAS and a smaller part showing minimal constriction.

• 전자공학회논문지SC
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• 제42권5호
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• pp.51-58
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• 2005

본 논문에서는 유방 초음파 볼륨영상에서 진단하고자 하는 종양 영역을 율왜곡 기반(rate-distortion based) 시드영역 확장 법으로 분할하는 알고리듬을 제안한다. 제안된 분할법에서는 율은 윤곽의 거친 정도를 나타내고 왜곡은 영역의 동질성 정도를 나타내는데, 흉부 종양 볼륨으로부터 획득한 2차원 단면 영상에서 설정된 초기 시드영역에서 시작하여 이러한 율과 왜곡을 동시에 최소화하는 주위영역 중 하나씩 시드영역으로 병합한다. 이러한 병합은 시드영역의 윤곽 화소당 평균 율왜곡 비용이 최대가 될 때까지 반복적으로 수행한다. 이렇게 함으로써 최종 시드영역은 동질성이 잘 유지되고 부드러운 윤곽을 갖게 된다. 마지막으로 모든 단면 영상에 있는 최종 시드영역의 윤곽들을 이용하여 3차원 흉부 종양을 추출한다. 실험 결과, 제안한 방법이 초음파 데이터에 대하여 평균 에러율이 약 4% 미만으로 나타났다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제31권2호
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• pp.130-136
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• 2005

Bone grafts are widely used in the reconstruction of osseous defects in the oral and maxillofacial region. Autogenous bone grafts are considered the gold standard in grafting of the oral and maxillofacial region, because of its osteoconductive and osteoinductive properties. Mandibular symphysis & ascending ramus bone graft have been used more frequently because of easy surgical access, reduced operative time, and following minimal morbidity. However, even though the frequent use of the anterior part of ascending ramus and the different regions of mandible, rare of the reports provide information about the quantity of bone available in this donor site. So this study was taken to evaluate & quantify the amount of bone graft material in the anterior ascending ramus regions. This study was made on 36 samples of CT image. In 3D volume image, imaginary osteotomy & segmentation were done and the dimensions and volume of the bone grafts were measured and evaluated. the average volume of the graft materials obtained from the ascending ramus was $3656.83{\pm}108.19mm^3$, and the average dimensions of graft materials were $(33.68{\pm}0.48){\times}(34.92{\pm}0.51){\times}(15.96{\pm}0.27){\times}(9.05{\pm}0.27)mm$.

• 한국ITS학회 논문지
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• 제2권1호
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• pp.41-52
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• 2003

본 연구의 목적은 기존 신호운용체계의 효율적인 운용과 안전한 보행자 통행시간을 보장한다는 전제하에, 신호교차로 에서 보행자신호로 인해 발생하는 불합리한 좌회전차량의 꼬리물림현상과 우회전차량 진행불가현상이 직진 교통류에 미치는 소통장애를 해소하는 방안을 제시하는 것이다. 본 연구에서 제시하는 방안은 차량직진신호 점등 후 몇 초 정도의 시차(步行者信號 前時間)를 두고 보행자신호를 운용함으로써 보행이 시작되기 전에 회전교통류가 교차로에서 소거되도록 하는 것이다. 이를 위하여 첨두시간에 교차로에서 보행자신호 전시간을 점차 확장시키는 방법으로 좌회전 꼬리물림$\cdot$우회전 진행불가차량 발생현상을 현장조사 하였으며, 분석결과는 다음과 같다. 첫째, 보행자신호 전시간을 연장할수록 직진교통류 소통장애를 야기하는 좌회전 꼬리물림현상과 우회전 진행불가현 상이 현저히 감소하였다. 둘째, 교차로와 횡단보도간의 대기공간이 수용할 수 있는 범위 내에서는 좌회전 꼬리물림차량과 우회전 진행불가차량도 직진차량에 장애를 주지 않았다. 셋째, 이중 횡단보도에서는 신호현시체계상 좌회전 꼬리물림현상이 발생치 않으며 우회전 진행불가현상은 충분한 대기공간으로 인해 직진차량에 미치는 영향이 미미하였다. 검증 결과 보행자신호 전시간 부여는 교차로 소통효율성 증진에 유의한 것으로 판단되었으며 이를 운용하기 위해서는 회전교통량과 횡단보도의 위치$\cdot$종류에 따라 개개 교차로별로 보행자신호 전시간이 설정되어야 한다는 결론을 얻었다.

• Journal of Periodontal and Implant Science
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• 제51권6호
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• pp.398-408
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• 2021

Purpose: In this study, we aimed to evaluate the clinical validity of the modified tunneling technique using minimal soft tissue harvesting and volume-stable collagen matrix in the anterior mandible. Methods: In total, 27 anterior mandibular teeth and palatal donor sites in 17 patients with ≥1 mm of gingival recession (GR) were analyzed before and after root coverage. For the recipient sites, vertical vestibular incisions were made in the interdental area and a subperiosteal tunnel was created with an elevator. After both sides of the marginal gingiva were tied to one another, a prepared connective tissue graft and volume-stable collagen matrix were inserted through the vestibular vertical incision and were fixed with resorbable suture material. The root coverage results of the recipient site were measured at baseline (T₀), 3 weeks (T₃), 12 weeks (T₁₂), and the latest visit (T_l). For palatal donor sites, a free gingival graft from a pre-decided area avoiding the main trunk of the greater palatine artery was harvested using a prefabricated surgical template at a depth of 2 mm after de-epithelization using a rotating bur. In each patient, the clinical and volumetric changes at the donor sites between T₀ and T₃ were measured. Results: During an average follow-up of 14.5 months, teeth with denuded root lengths of 1-3 mm (n=12), 3-6 mm (n=11), and >6 mm (n=2) achieved root coverage of 97.01%±7.65%, 86.70%±5.66%, and 82.53%±1.39%, respectively. Miller classification I (n=12), II (n=10), and III (n=3) teeth showed mean coverage rates of 97.01%±7.65%, 86.91%±5.90%, and 83.19%±1.62%, respectively. At the donor sites, an average defect depth of 1.41 mm (70.5%) recovered in 3 weeks, and the wounds were epithelized completely in all cases. Conclusions: The modified tunneling technique in this study is a promising treatment modality for overcoming GR in the anterior mandible.

• 한국정보과학회논문지:시스템및이론
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• 제29권8호
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• pp.463-471
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• 2002

가상 내시경을 구현하기 위해서는 세밀하고 정확한 원근 투영 영상의 고속생성과 충돌검출이 필수적이다. 본 논문에서는 고속 원근 볼륨 렌더링 기법을 이용하여 정확하면서도 빠른 렌더링이 가능한 가상 내시경 기술을 제안한다. 이 방법은 기본적으로 화질이 우수한 광선 투영법을 기반으로 하며 거리정보(distance information)를 이용하여 투명한 공간을 비약하도록 함으로써 렌더링 속도를 향상시키도록 하였다. 렌더링 시에는 광선의 진행 방향에 따라 샘플 간격을 가변적으로 조절하는 방법을 이용하여 화질의 손실을 최소화하면서 처리시간을 향상시킨다. 또한 전처리 단계에서 생성된 거리 정보를 이용하여 충돌 검출을 간단히 할 수 있는 방법을 제안한다.

• 한국레이저가공학회지
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• 제18권4호
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• pp.17-22
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• 2015

In this paper, ablation rate of $Al_2O_3$ ceramics by femtosecond laser fluence is derived with experimental method. The automatic three axis linear stage makes laser optics to move with high spatial resolution. With 10 times objective lens, minimal pattern width of $Al_2O_3$ is measured in the focal plane. Ablated surface area is shown as linear tendency increasing number of machining times with various laser power conditions. Machining times is most sensitive condition to control $Al_2O_3$ pattern width. Also, the linear increment of pattern width with laser power change is investigated. In high machining speed, the ablation volume rate is more linear with fluence because pulse overlap is minimized in this condition. Thermal effect to surrounding medium can be minimized and clean laser process without melting zone is possible in high machining speed. Ablation volume rate decelerates as increasing machining times and multiple machining times should be considered to achieve proper ablation width and depth.