• 제목/요약/키워드: thinning technique

검색결과 110건 처리시간 0.031초

Measuring rheological properties using a slotted plate device

  • Kee, Daniel-De;Kim, Young-Dae;Nguyen, Q. Dzuy
    • Korea-Australia Rheology Journal
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    • 제19권2호
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    • pp.75-80
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    • 2007
  • The slotted plate technique has previously been shown to be a successful method for directly measuring the static yield stress of suspensions. In this study, we further establish the usefulness of the slotted plate device as a rheometer especially at low shear rates, taking advantage of the extremely low speeds of the slotted plate technique. Newtonian fluids, a shear thinning fluid, and yield stress fluids were tested using the slotted plate device and the results were compared with those from a commercial rheometer using different standard flow geometries. The relationship between the stress on the plate and the viscosity for the slotted plate device obtained by dimensional analysis (drag) predicts a linear relationship between the force at the plate and the plate speed, consistent with the experimental data. The slotted plate device can measure viscosities at very low shear rates. The apparent viscosity - shear-rate data obtained from the slotted plate device are complementary to those obtained using a commercial rheometer. That is : the slotted plate can measure viscosity in the shear rate range $10^{-7}<\dot{\gamma}<10^{-3}\;s^{-1}$, while the commercial rheometer measures viscosity at shear rates higher than $10^{-3}\;s^{-1}$.

Delayed bipedicled nasolabial flap in facial reconstruction

  • Goh, Cindy Siaw-Lin;Perrett, Joshua Guy;Wong, Manzhi;Tan, Bien-Keem
    • Archives of Plastic Surgery
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    • 제45권3호
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    • pp.253-258
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    • 2018
  • Background The nasolabial flap is ideal for reconstruction of the nasal alar subunit due to its proximity, color and contour match, and well-placed donor scar. When raised as a random-pattern flap, there is a risk of vascular compromise to the tip with increased flap length and aggressive flap thinning. Surgical delay can greatly improve the chances of tip survival, allowing the harvest of longer flaps with greater reach. Methods We describe our technique of lengthening the nasolabial flap through multiple delay procedures. A bipedicled flap was first raised and then transferred as a unipedicled flap with a 6:1 length-to-width ratio. During the delay process, the flap tip was thinned to the subdermal layer. Results In our case series of seven patients, defects as far as the medial canthal area and contralateral ala were reconstructed successfully with no incidence of tip necrosis or flap loss. The resultant flaps were thin enough to be folded over for the reconstruction of alar rim defects. Conclusions We highlight the success of our surgical technique in creating thin and robust nasolabial flaps for the reconstruction of full-thickness defects around the nose.

신경회로망을 이용한 지문인식방법에 관한 연구 (A Study on the Fingerprint Recognition Method using Neural Networks)

  • 이주상;이재현;강성인;김일;이상배
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2000년도 추계학술대회 학술발표 논문집
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    • pp.287-290
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    • 2000
  • In this paper we have presented approach to automatic the direction feature vectors detection, which detects the ridge line directly in gray scale images. In spite of a greater conceptual complexity, we have shown that our technique has less computational complexity than the complexity of the techniques which require binarization and thinning. Afterwards a various direction feature vectors is changed four direction feature vectors. In this paper used matching method is four direction feature vectors based matching. This four direction feature vectors consist feature patterns in fingerprint images. This feature patterns were used for identification of individuals inputed multilayer Neural Networks(NN) which has capability of excellent pattern identification.

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배꼽주위 관통지를 이용한 유리 피판 (Paraumbilical Perforator Skin Flap)

  • 박명철;신예식;이병민;김관식
    • Archives of Reconstructive Microsurgery
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    • 제5권1호
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    • pp.92-98
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    • 1996
  • The rectus abdominis myocutaneous flap is frequently used in the field of plastic and reconstructive surgery such as breast reconstruction and as a donor of free tissue transfer. Major problems with this flap is bulkiness, the possibility of postoperative abdominal herniation and muscle weakness following the removal of the rectus abdominis muscle. We used paraumbilical perforator based skin flap fed by a muscle perforator from the deep inferior epigastric artery, with no or little muscle and fatty tissue, in three patients for the resurfacing of relatively wide and thin defects. This technique has all of the advantages of the conventional rectus abdominis myocutaneous flap with decreased possibility of postoperative abdominal herniation or muscle weakness. Another challenging merit is possibility of skin flap thinning.

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새로운 연산자를 이용한 통계적인 윤곽선 추출기법 (Statistical Edge Detecting Method Using a New operator.)

  • 이해영;김훈학;이근영
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(II)
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    • pp.1394-1397
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    • 1987
  • It is difficult to detect edge segments from a noisy image since the image have a noise in piratical applications which utilize some type of visual input capability. Hence, the proposed algorithm consists of the modality tests based on parallel statistical tests without a noise removal preprocessing or postprocessing, and the edge detection technique With one-Pixel edge segments in this paper. The algorithm is very reliable and effective in the case of those situations where the Picture is poor quality and low resolution. And it does'nt require thinning operation and thresholding in hand. Experimental comparision With the more conventional techniques when applied to typical low-quality Pictures confirms good capabilities of the algorithm.

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분석전자현미경용 다층박막 디스크의 시편준비법 (TEM sample preparation of thin film multilayer disks for analytical electron microscopy)

  • 김명룡
    • E2M - 전기 전자와 첨단 소재
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    • 제8권4호
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    • pp.464-471
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    • 1995
  • 메그네트론 스퍼터링으로 제작한 고밀도 다층박막($Co_75{{Pt_12}{Cr_13}}$합금) 디스크를 투과전자현미경을 이용해 단면 및 평면의 미세조직의 조사 혹은 미소부위 성분분석을 할 경우, 선행되어야하는 시편준비 경로와 각 단계별 구체적방법 및 그 효과를 연구하였다. Ion밀링시간이 증가함에 따라 시료가 얇게 되는과정에서 스퍼터링된 물질이 관찰될 시편부위의 다른 표면에 증착되므로써 미세조직의 선명도를 해칠 수 있고, 이로인한 해석상의 오류가능성이 시사되었다. 또한, 자기박막 디스크와 같이 다층으로 구성된 단면분석용 시료에서는 서로 맞붙인 실리콘 단결정 접착면을 따라 밀링속도가 선택적으로 커서 우선축이 생김으로써 양질의 시편을 얻기 어려운 문제점이 제기되었다. 이같은 문제를 포함한 전자현미경 시료준비과정에서 생길 수 있는 문제를 해결할 수 있는 실마리와 이를 이용해 수행한 전자현미경 분석결과 및 효과적인 시편준비방법이 본 논문에서 언급되었다.

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유한요소법을 이용한 초소성 성형/확산접합 공정해석 (Analysis of superplastic forming/diffusion bonding process using a finite element method)

  • 송재선;김용환;홍성석;강영길;이정환;권용남
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2006년도 춘계학술대회 논문집
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    • pp.265-268
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    • 2006
  • The superplastic forming/diffusion bonding is widely accepted as an advanced technique for forming complex industrial components. But the superplastic forming process requires much forming time and generates excessive thinning thickness distribution of formed part. Superplastic in materials is only achieved in a narrow range of strain-rate with optimum value unique to each material. In this study, finite element analysis for surperplastic forming/diffusion bonding (SPF/DB) processes of three-sheet and four-sheet sandwich parts. From this study, forming analysis have offered a lot of information for developing the forming process.

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허프변환과 차선모델을 이용한 효과적인 차선검출에 관한 연구 (Study on Effective Lane Detection Using Hough Transform and Lane Model)

  • 김기석;이진욱;조재수
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2009년도 정보 및 제어 심포지움 논문집
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    • pp.34-36
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    • 2009
  • This paper proposes an effective lane detection algorithm using hugh transform and lane model. The proposed lane detection algorithm includes two major components, i.e., lane marks segmentation and an exact lane extraction using a novel postprocessing technique. The first step is to segment lane marks from background images using HSV color model. Then, a novel postprocessing is used to detect an exact lane using Hugh transform and lane models(linear and curved lane models). The postprocessing consists of three parts, i.e, thinning process, Hugh Transform and filtering process. We divide input image into three regions of interests(ROIs). Based on lane curve function(LCF), we can detect an exact lane from various extracted lane lines. The lane models(linear and curved lane mode]) are used in order to judge whether each lane segment is fit or not in each ROIs. Experimental results show that the proposed scheme is very effective in lane detection.

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MEMS 기술을 이용한 Flexible Module (Flexible Modules Using MEMS Technology)

  • 김용준;황은수;김용호;이태희
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2003년도 춘계학술대회 논문집
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    • pp.223-227
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    • 2003
  • A new flexible electronic packaging technology and its medical applications are presented. Conventional silicon chips and electronic modules can be considered as "mechanically rigid box." which does not bend due to external forces. This mechanically rigid characteristic prohibits its applications to wearable systems or bio-implantable devices. Using current MEMS (Microelectromechanical Systems) technology. a surface micromachined flexible polysilicon sensor array and flexible electrode array fer neural interface were fabricated. A chemical thinning technique has been developed to realize flexible silicon chip. To combine these techniques will result in a realization of truly flexible sensing modules. which are suitable for many medical applications.

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박리없는 복부성형술의 경험 (Experiences of Abdominoplasty without Undermining)

  • 심형보;윤상엽
    • Archives of Plastic Surgery
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    • 제33권3호
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    • pp.303-307
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    • 2006
  • No one technique provides an optimal outcome for all body contouring patients. There are many surgical options for abdominoplasty. Among these, this abdominoplasty without undermining consists of liposuction around abdominal subcutaneous fatty tissue, excision of lower abdominal flap. The procedure allows aggressive thinning and sculpting of abdominal flap. This operation minimizes the dead space, which often leads to postoperative complications, and preserves neurovascular supply to the abdominal skin. From 1999 to 2004, 18 patients underwent the abdominoplasty without undermining, resulting in high satisfaction rates with no significant complications, such as, pulmonary embolism and deep vein thrombosis. Patients could return to normal activity within a week. This abdominoplasty without undermining is an effective and safe alternative with low complication rate and enhances aesthetic results compared to traditional abdominal surgery.