• Clinics in Shoulder and Elbow
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• v.18 no.4
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• pp.211-216
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• 2015

Background: Few studies have investigated magnetic resonance (MR) characteristics of traumatic posterosuperior rotator cuff tears involving the supraspinatus and infraspinatus. We hypothesized that traumatic rotator cuff tears may have MR characteristics distinguishable from those of non-traumatic tears. Methods: Preoperative MR arthrography and intraoperative tear size measurements were compared in 302 patients who underwent MR arthrography and subsequent arthroscopic rotator cuff repairs for traumatic (group T, 61 patients) or non-traumatic (group NT, 241 patients) tears. The inclusion criteria for both groups were posterosuperior full-thickness rotator cuff tear and age between 40 and 60 years. For group T, traumas were limited to accidental falls or slips, or sports injuries, motor vehicle accidents; injuries were associated with acute onset of pain followed by functional shoulder impairment; and time between injury and magnetic resonance imaging (MRI) was 6 weeks or less. Results: In group T, 72.1% of shoulders (44 patients) had tendon tears with blunt edges while 27.9% of shoulders (17 patients) had tears with tapering edges. In contrast, 21.2% of patients in group NT (51 patients) had blunt-edge tears, while 78.8% (190 patients) of tears had tapering edges. These results were statistically significant (p<0.001) and estimated odds ratio was 9.6. The size of tear did not vary significantly between groups. Conclusions: We found no exclusive MR characteristic to define traumatic tears. However, oblique coronal MRI of traumatic tears showed a significant tendency for abrupt and rough torn tendon edges and relatively consistent tendon thicknesses (without lateral tapering) compared to non-traumatic cuff tears.

• Korean Journal of Head & Neck Oncology
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• v.24 no.1
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• pp.53-56
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• 2008

Objectives：The purpose of this study was to evaluate the variable sonographic features in addition to classic findings and to find the helpful characteristic findings for diagnosis of branchial cleft cysts. Subjects and Methods：We retrospectively analyzed the sonographic finding of 16 histopathologically proven branchial cleft cysts. Assessment involved the following variables : location related to carotid artery, size, cyst wall, border, margin, shape, internal echotexture, post echoic enhancement, orientation of longitudinal axis relative to the long axis of the neck, and tapering edge. Results：Most branchial cleft cysts were seen as well defined(15/16), oval shape(13/16), smooth inner (12/16) and outer margin(13/16), and post echoic enhancement(16/16). Their diameter varied from 1 to 6cm (mean 3.3cm). The branchial cleft cysts showed variable internal echopatterns；hyperechogenicity or pseudosolid appearance(1/16), heterogeneous echogenicity(4/16) in addition to classic form of anechoic(5/16) or hypoechoic internal echogenicity(6/16). Longitudinal axis of most branchial cleft cysts were arranged in the direction of the long axis of the neck(13/16) and some branchial cleft cysts had tapering edge(6/16). Conclusion：If both atypical sonographic findings and location are showed, longitudinal arrangement of long axis and tapering edge of branchial cleft cysts are helpful findings for differential diagnosis.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.2 no.1
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• pp.37-42
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• 1992

KDP단결정의 육성을 서냉법 및 정온법에 의해 행하였다. KDP용해도의 온도계수는 20-80℃의 측정온도 범위에서 positive였다. KDP종자결정은 수용액중의 육성온도가 30℃일 때 큰 결정으로 성장하였다. KDP단결정의 tapering효과는 산도, 과포화 및 육성온도에 의존하였다. KDP-ADP결정은 수용액중 33℃의 육성온도에서 얻을 수 있었다.

• Proceedings of the Korean Society For Composite Materials Conference
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• 1999.11a
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• pp.264-267
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• 1999

복합적층판은 일반적으로 균일한 두께를 갖는 평평한 구조물을 형성하게 된다. 그러나 실제 적용시 적층판의 테이퍼링(tapering)이 요구되는 경우가 존재한다. 테이퍼진 복합재 구조물의 적용분야는 항공기의 날개, 수직/수평 안정판 및 헬리콥터의 로터 블레이드 등이다. (중략)

• Journal of the Korean Institute of Telematics and Electronics
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• v.23 no.4
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• pp.490-497
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• 1986

The effectiveness of field plate and window tapering in reducing the maximum surface electric field of planar pn junctions has been studied by two dimensional computer simulation. The influence of silicon dioxide insulator thickness is also presented.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2010.03a
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• pp.121-122
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• 2010

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.125.2-125.2
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• 2016

Semiconductor nanowires are essential building blocks for various nanotechnologies including energy conversion, optoelectronics, and thermoelectric devices. Bottom-up synthetic approach utilizing metal catalyst and vapor phase precursor molecules (i.e., vapor - liquid - solid (VLS) method) is widely employed to grow semiconductor nanowires. Al has received attention as growth catalyst since it is free from contamination issue of Si nanowire leading to the deterioration of electrical properties. Al-catalyzed Si nanowire growth, however, unlike Au-Si system, has relatively narrow window for stable growth, showing highly tapered sidewall structure at high temperature condition. Although surface chemistry is generally known for its role on the crystal growth, it is still unclear how surface adsorbates such as hydrogen atoms and the nanowire sidewall morphology interrelate in VLS growth. Here, we use real-time in situ infrared spectroscopy to confirm the presence of surface hydrogen atoms chemisorbed on Si nanowire sidewalls grown from Al catalyst and demonstrate they are necessary to prevent unwanted tapering of nanowire. We analyze the surface coverage of hydrogen atoms quantitatively via comparison of Si-H vibration modes measured during growth with those obtained from postgrowth measurement. Our findings suggest that the surface adsorbed hydrogen plays a critical role in preventing nanowire sidewall tapering and provide new insights for the role of surface chemistry in VLS growth.

• The Journal of the Korea institute of electronic communication sciences
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• v.7 no.4
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• pp.867-871
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• 2012

In this paper, we proposed and demonstrated a low loss $1{\times}4$ type plastic optical fiber(POF) coupler incorporating a polymer tapering waveguide region. To avoid leakage loss at the interfaces between the POF and the polymer waveguide, we employed two POF transition regions, in which the cross section of the POF is adiabatically converted from a circular to a rectangular shape without change of its cross-section area. The device was fabricated based on a injection mold made of a silicon rubber. The fabricated POF coupler showed 1.33 dB of excess loss and 2.2 dB of flatness.

• Journal of Genetic Medicine
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• v.4 no.2
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• pp.196-199
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• 2007

Coffin-Lowry syndrome (CLS) is a rare X-linked hereditary disorder characterized by moderate to severe mental retardation, facial dysmorphism, tapering fingers, and skeletal deformity. A 12-month-old boy was referred to our pediatric clinic for his developmental delay and seizure with fever. The boy exhibited a coarse facial appearance characterized by prominent, high-arched eyebrow, broad nose, downward palpebral fissure, high arched palate, hypodontia. The boy also showed finger tapering and puffy hand. Hypotonia, hyperextensible fingers and hypermobility of the joint were seen. Based on these findings, he was diagnosed as having Coffin-Lowry syndrome. We report a case of Coffin-Lowry syndrome with reference.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.3
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• pp.333-340
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• 2011

We evaluated the stress-reduction effect for different shapes of a composite adherend with or without a spew fillet. Six different single-lap joint specimens were modeled and assessed using nonlinear finite element analysis. Moreover, we investigated the effect of the stiffness ratio of the adherend and adhesive. The single-lap joint with normal tapering had the highest stress values, and the single-lap joint with reverse tapering and a spew fillet had the lowest stress values. The composite adherends with higher stiffness had lower stress values, and the adhesives with lower stiffness had lower stress values.