• 마이크로전자및패키징학회지
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• 제18권4호
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• pp.49-53
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• 2011

TSV(through-silicon-via)를 이용한 3차원 Si 칩 패키징 공정 중 전기 도금을 이용한 비아 홀 내 Cu 고속 충전과 범핑 공정 단순화에 관하여 연구하였다. DRIE(deep reactive ion etching)법을 이용하여 TSV를 제조하였으며, 비아홀 내벽에 $SiO_2$, Ti 및 Au 기능 박막층을 형성하였다. 전도성 금속 충전에서는 비아 홀 내 Cu 충전율을 향상시키기 위하여 PPR(periodic-pulse-reverse) 전류 파형을 인가하였으며, 범프 형성 공정에서는 리소그라피(lithography) 공정을 사용하지 않는 non-PR 범핑법으로 Sn-3.5Ag 범프를 형성하였다. 전기 도금 후, 충전된 비아의 단면 및 범프의 외형을 FESEM(field emission scanning electron microscopy)으로 관찰하였다. 그 결과, Cu 충전에서는 -9.66 $mA/cm^2$의 전류밀도에서 60분간의 도금으로 비아 입구의 도금층 과성장에 의한 결함이 발생하였고, -7.71 $mA/cm^2$에서는 비아의 중간 부분에서의 도금층 과성장에 의한 결함이 발생하였다. 또한 결함이 생성된 Cu 충전물 위에 전기 도금을 이용하여 범프를 형성한 결과, 범프의 모양이 불규칙하고, 균일도가 감소함을 나타내었다.

• Journal of information and communication convergence engineering
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• 제12권1호
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• pp.46-52
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• 2014

This article presents key research needs in three-dimensional integrated circuit (3D IC) architectural floorplanning. Architectural floorplaning is done at a very early stage of 3D IC design process, where the goal is to quickly evaluate architectural designs described in register-transfer level (RTL) in terms of power, performance, and reliability. This evaluation is then fed back to architects for further improvement and/or modifications needed to meet the target constraints. We discuss the details of the following research needs in this article: block-level modeling, through-silicon-via (TSV) insertion and management, and chip/package co-evaluation. The goal of block-level modeling is to obtain physical, power, performance, and reliability information of architectural blocks. We then assemble the blocks into multiple tiers while connecting them using TSVs that are placed in between hard IPs and inside soft IPs. Once a full-stack 3D floorplanning is obtained, we evaluate it so that the feedback is provided back to architects.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제16권3호
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• pp.464-472
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• 1994

Surgical removal of the submandibular gland via intraoral approach was performed. The surgical procedure to be used for removal of submandibular gland had been performed via extraoral approach for many centuries. Disadvantages of extraoral technique are the esthetic distress due to an external scar, residual inflammation in Wharton's duct, and neurological complications. Indications of intraoral approach are unlimited in surgical cases of submandibular gland. Advantages of intraoral approach are esthetic satisfaction due to no remaining scars, preservation of adjacent anatomical structures and preservation of lower facial contour. This paper describes the surgical technique of the submandibular gland excision through an intraoral approach and variable incision lines tried. In 7 cases, excellent results were obtained after removal of the submandibular gland through an intraoral approach.

• Acta Via Serica
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• 제1권1호
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• pp.51-67
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• 2016

This article examines the nature of geopolitics and its impact on the international political economy of Eurasia/Silk Road. The research questions are exploratory and aim at revealing the differing geopolitical perceptions of the Russian Federation, the People's Republic of China (PRC) and the former Soviet Central Asian countries-Uzbekistan, Turkmenistan, Tajikistan Kyrgyzstan and Kazakhstan-within the context of an emerging "New Silk Road". Consequently, the main goal of this article is to contribute to a better understanding of what factors constrain and shape Silk Road initiatives in Eurasia. To this end, the article focuses on geopolitics and regional integration theories through a consideration of the Silk Road initiatives of a number of Eurasian countries.

• Elastomers and Composites
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• 제51권2호
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• pp.138-146
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• 2016

It is an inconvenience for silica nano-particles to dry again when using it in that they cohere each other through moisture in the air. Acrylamide groups were introduced to improve such inconvenience and copolymerized with silica nano-particles and then we copolymerized again with polyamic acid in order to increase thermal characteristic. Amide block copolymers were prepared using silica and (3-mercaptopropyl) trimethoxysilane (MPTMS) with a siloxane group, using 2,6-Lutidine as a catalyst. Amide block polymers and copolymers were synthesized via ATRP after brominating pyromellitic dianhydride (PMDA) and polyamic acid of methylene diphenyl diamine (MDA), using ${\alpha}$-bromo isobutyryl bromide. Characteristic peaks of copolymer with amide and imide groups and patterns of amorphous polymers were researched by FT-IR and XRD analyses and the analysis of surface characteristic groups was conducted via XPS. A change in thermal properties was examined through DSC and TGA and solubility for solvents was also researched.

• Advances in materials Research
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• 제6권4호
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• pp.349-361
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• 2017

The nonlinear thermal buckling load parameter of the laminated composite panel structure is investigated numerically using the higher-order theory including the stretching effect through the thickness and presented in this research article. The large geometrical distortion of the curved panel structure due to the elevated thermal loading is modeled via Green-Lagrange strain field including all of the higher-order terms to achieve the required generality. The desired solutions are obtained numerically using the finite element steps in conjunction with the direct iterative method. The concurrence of the present nonlinear panel model has been established via adequate comparison study with available published data. Finally, the effect of different influential parameters which affect the nonlinear buckling strength of laminated composite structure are examined through numerous numerical examples and discussed in details.

• Acta Via Serica
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• 제3권2호
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• pp.161-180
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• 2018

Pax Sinica is a historiographical term, modeled after the original phrase Pax Romana. It refers, in Latin, to a Chinese-provided peace which in turn is used to describe an era of peace in East Asia sustained by Chinese hegemony. In historical terms, both the Pax Sinica of the Eastern hemisphere through Han China and the Pax Romana of the Western hemisphere through Rome signified a trans-regional order based on rules and regulations. This orderly world of the Pax Sinica generated a number of positive results such as the intensification of travel, ever-expanding trade relations, an increase in the overall living standards of the populace, the proliferation of cities, and a demographic upsurge in Eurasia along the ancient Silk Road. During this period, China was the dominant civilization not only in the Eastern hemisphere but also in the Middle hemisphere due to its political, economic, military and cultural influence. This paper aims to reintroduce this historiographical term to elucidate the recent Chinese initiatives in Eurasia along the Silk Road to facilitate the integration and connectivity of the continent.

• Communications for Statistical Applications and Methods
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• 제26권5호
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• pp.473-495
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• 2019

In this paper, a new extension of Lindley distribution has been introduced. Certain characterizations based on truncated moments, hazard and reverse hazard function, conditional expectation of the proposed distribution are presented. Besides, these characterizations, other statistical/mathematical properties of the proposed model are also discussed. The estimation of the parameters is performed through different classical methods of estimation. Bayes estimation is computed under gamma informative prior under the squared error loss function. The performances of all estimation methods are studied via Monte Carlo simulations in mean square error sense. The potential of the proposed model is analyzed through two data sets. A modified goodness-of-fit test using the Nikulin-Rao-Robson statistic test is investigated via two examples and is observed that the new extension might be used as an alternative lifetime model.

• Journal of Trauma and Injury
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• 제32권2호
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• pp.122-125
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• 2019

A 73-year-old man, who, in an inebriated state, had slipped in a flowerbed and was wounded on the left flank, was transferred to Trauma Center, Gil Medical Center, Gachon University College of Medicine. Based on the chest and abdominopelvic computed tomography, he was diagnosed with multiple rib fractures and hemopneumothorax on the left hemithorax and was found to have a bony fragment in the spleen. He had not presented peritonitis and exsanguinous symptoms during the observation period. Seven days later, computed tomography of the abdomen showed suspected diaphragmatic injury and a retained foreign body in the spleen. On exploration by video assisted thoracoc surgery (VATS), a herniated omentum through the lacerated site of the diaphragm was observed. After omentectomy using Endo Gia, the foreign body in the spleen was observed through the lacerated site of the diaphragm. Traumatic diaphragm rupture with a foreign body, in the spleen, was successfully managed by video assisted thoracic surgery via the lacerated site of the diaphragm.

• Bulletin of the Korean Chemical Society
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• 제17권2호
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• pp.153-158
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• 1996

The synthesis of common skeleton of podosporin A and aureol was studied through cationic olefin cyclization as a key step. The generation of thermodynamic silyl enol ether or enol acetate under known conditions gave regioselectivity of 88:12. The enolate alkylation of 2,3-dimethylcyclohexanone with 2,5-dimethoxybenzyl bromide at the more substituted site via lithium enolate gave poor yield. In this case an organozincate or an ammonium enolate also proved to be ineffective or not practical in terms of yield. Side chain elongation of the substituted cyclohexanone 13 through Grignard reaction, Wittig reaction, or Shappiro reaction did not proceed because of steric hindrance and side reactions. However, Stille coupling reaction via enol triflate produced the desired product 18 in high yield. The advanced intermediate 22, which was efficiently synthesized from 18, produced 24 instead of the desired product under a cationic olefin cyclization condition, indicating that the cyclization occurred in a stepwise mannervia the organomercury intermediate 23.