• 한국IT서비스학회지
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• 제11권2호
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• pp.19-47
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• 2012

Contemporary smartphone competition is generally described as the battle between Apple's proprietary platform and Google's open platform. However, this competition is not limited within smartphone adoption itself. User's pre-adoption of one mobile platform via smartphone can be connected to the post-adoption of the same mobile platform based on the other smart devices (e.g. smart pad). In this study, we investigate whether user's preference to a certain platform is persistent over mobile ecology, from the pre-adoption of one smart device to the post-adoption of following devices. For this investigation, we adopt the dual-model as the ground theory, where post-adoption of IT product is explained by both dedication and constraint factors. The empirical testing first evidences that dual model works well as our research model for identifying the reasons of post-adoption. Next, we group our data into two parts in order to compare the switching behavior of iPhone users and Android phone users. iPhone users show much lower switching rate to Android based smart pads, while Android phone users show higher churn rate to iPad (49.3% : 96.3%). Especially, satisfaction showed much stronger effect than switching cost on the continuing intention of existing platform, when the analysis is given to the iPhone user's group. From this result, we can conjecture the relatively stronger loyalty of iPhone users. More managerial implications on the mobile platform strategy are driven.

• Tribology and Lubricants
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• 제28권6호
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• pp.265-271
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• 2012

In the preceding Part I study, for improving the unbalance response vibration of a large PRT motor-generator rotor fundamentally by design, a series of design analyses were carried out for bearing improvement by retrofitting from original plain partial journal bearings, applied for operation at a rated speed of 1,800 rpm, to final tilting pad journal bearings. To satisfy evenly key basic lubrication performances such as the minimum lift-off speed and maximum oil-film temperature, a design solution of 5-pad tilting pad journal bearings and maximizing the direct stiffness by about two times has been achieved. In this Part II study, a detailed rotordynamic analysis of the large PRT motor-generator rotor-bearing system will be performed, applying both the original plain partial journal bearings and the retrofitted tilting pad journal bearings, to confirm the effect of rotordynamic vibration improvement after retrofitting. The results show that the rotor unbalance response vibrations with the tilting pad journal bearings are greatly reduced by as much as about one ninth of those with the plain partial journal bearings. In addition, for the tilting pad journal bearings there exist no critical speed up to the rated speed and just one instance of a concerned critical speed around the rated speed, whereas for the plain partial journal bearings there exist one instance of a critical speed up to the rated speed and two instances of concerned critical speeds around the rated speed.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2013년도 춘계학술대회 논문집
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• pp.463-464
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• 2013

• 동의생리병리학회지
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• 제18권3호
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• pp.783-788
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• 2004

Cheonmabanhwa- Tang (CBT) has been used in the Oriental Medicine for many centuries as a therapeutic agent for dizziness due to Poong-Dam, We reported that CBT had effects on the cerebral hemodynamics [regional cerebral blood flow (rCBF), pial arterial diameter (PAD), and mean arterial blood pressure (MABP)] in normal and cerebral ischemic rats. Therefor we designed to determine the mechanism of action of CBT. The changes of rCBF and MABP were determinated by laser-Doppler flowmetry(LDF), and the change of PAD was determinated by video-microscopy. The results were as follows: The CBT-induced increase in rCBF was significnatly inhibited by pretreatment with indomethacin (IDN, 1 ㎎/㎏, i.p.), an inhibitor of cyclooxygenase, or methylene blue (MTB, 10 ㎍/㎏, i.p.), an inhibitor of guanylate cyclase. The CBT-induced increase in PAD was also significantly inhibited by pretreatment with IDN or MTB. The CBT-induced increase in MABP was also significantly inhibited by pretreatment with IDN or MTB. In conclusion, it is suggested that CBT causes a diverse effect on cerebral hemodynamics via mediation of cyclooxygenase and guanylate cyclase.

• 한국콘텐츠학회논문지
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• 제11권12호
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• pp.171-181
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• 2011

본 연구는 전자책 독서경험의 변별자질을 '체험성'으로 전제하고 이를 증명하는데 목적을 둔다. 전자책은 개념적으로 '책'에 그 기반을 두고 있는 만큼, 인문학적인 관점에서 전자책이 '책'의 개념을 어떻게 계승, 변형, 확장하는가에 대해 논할 필요가 있다. 이에 본 연구는 앱북 형식의 전자책 을 대표분석 텍스트로 삼아 전자책의 체험성을 분석했다. 은 아이패드용으로 출시된 앱북으로, 작가인 주이커는 TV 범죄수사드라마 시리즈인 C.S.I.에 참여했던 창작자이기도 하다. 그는 자신의 소설을 '디지노벨'이라 규정짓는다. 디지노벨은 동일한 내용의 소설을 세 가지 읽기 방식-전통텍스트형(Traditional Version), 디지노벨형(Digi-Novel Version), 얼티메이트 디지노벨형(Ultimate Digi-Novel Version)-으로 제시한다. 따라서 같은 내용의 전자책 콘텐츠라 할지라도 상호작용과 멀티미디어적 변수에 따라 사용자의 독서경험이 달리진다는 것을 증명하기에 적절하다. 분석 결과에 따르면, 전자책 콘텐츠는 미디어적 특성상 대중적 취향과 관습적 내용을 따르며, 독자의 신체 개입을 통해 체험을 확장해나간다. 따라서 전자책의 체험성을 높이기 위해서는 체험의 요소가 반드시 서사 구조 내에서 유의미한 극적 요소와 연결되어야 한다.

• 한국정밀공학회지
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• 제13권11호
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• pp.46-56
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• 1996

Planarization technique is rapidly recognized as a critical step in chip fabrication due to the increase in wiring density and the trend towards a three dimensional structure. Global planarity requires the preferential removal of the projecting features. Also, the several materials i.e. Si semiconductor, oxide dielectric and sluminum interconnect on the chip, should be removed simultaneously in order to produce a planar surface. This research has investihgated the development of the chemical mechanical polishing(CMP) machine with uniform pressure and velocity mechanism, and the pad insensitive to pattern topography named hard grooved(HG) pad for global planarization. Finally, a successful result of uniformity less than 5% standard deviation in residual oxide film and planarity less than 15nm in residual step height of 4 inch device wafer, is achieved.

• 한국의류학회지
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• 제41권5호
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• pp.939-949
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• 2017

This study uses 3D printing technology to design and fabricate a fall impact protection pad with a spacer fabric structure. The design of the pads consists of hexagonal three-dimensional units connected in a honey-comb shape; in addition, the unit consists of a surface layer and a spacer layer. Protect pads were designed as either a hexagonal type or diamond type according to the surface layer structure; subsequently, a spacer filament was also designed as the most basic I-shape type. Designed pads were printed using four types of flexible filaments to select suitable material for a fall impact protection pad. Impact protection performance and bending stiffness were evaluated for the eight type of pad outputs. As a result of the impact protection performance evaluation, when the force of 6,500N was applied, the force passed through the pad was in the range of 1,370-2,132N. FlexSolid$^{(R)}$ and Skinflex$^{TM}$ showed good protection performance and cubicon flexible filament showed the lowest protection. NinjaFlex$^{(R)}$ was found to be the most flexible in the bending stiffness evaluation.

• 한국전문물리치료학회지
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• 제27권4호
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• pp.250-256
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• 2020

Background: Unstable surface-based core training can significantly enhance core strength, but no studies have compared the effects of balance pad- and sling-assisted exercises. Objects: To study the effects of unstable surface-based balance pad- and sling-assisted core strength exercises on muscle activity. Methods: Twenty male students aged 20-25 years participated in this study. The effects of three types of core strength exercises, performed with a sling or balance pad, on the activities of three muscles, i.e., the right musculus obliquus externus abdominis (EO), right erector spinae (ES), and right gluteus maximus (GM), were examined. Results: 1) In the glute bridge exercise, the percentage of maximum voluntary contraction of the EO, ES, and GM were significantly different between the balance pad- and sling-assisted exercises. The relative contribution of the ES and GM activities to all muscle activity were not significantly different between the two training types, whereas that for EO showed a significant difference. 2) There was no significant difference in the percentage value of maximum voluntary contraction (%MVC) among the EO, ES, and GM during the "leg-lifting with flat support" exercise, and there were no significant difference in the relative contributions between the two training types. 3) In the "side bridge leg separation exercise", the %MVC of the ES, EO, and GM were significantly different between the two training types. Conclusion: Sling training for core muscles was generally better than balance pad assist training. The majority of physiotherapy patients require core training. Our results could guide physiotherapists in the choice of targeted exercises for these patients.

• Nuclear Engineering and Technology
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• 제37권6호
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• pp.565-574
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• 2005

The CANFLEX Mk-V bundle is designed to improve upon the critical heat flux (CHF) characteristics of the CANFLEX Mk-IV bundle. The main difference between these two bundles is an increase in bearing pad height of about 0.3 mm in the CANFLEX Mk-IV bundle. This change in bearing pad height leads to an increase in gap flow at the bottom of the bundle, primarily eliminating the localized narrow-gap effect that limits the CHF of the CANFLEX Mk-IV bundle. The objective of this paper is to examine the effects of bearing pad height and pressure tube creep on the sheath-temperature distribution, dryout power, and dryout location, as observed ken full-scale bundle tests, between CANFLEX Mk-IV and Mk-V bundles In uncrept and crept channels. A comparison of surface-temperature differences between the top and bottom elements of the bundles showed that increasing the bearing pad height has led to a more homogeneous enthalpy distribution in subchannels of the bundle. Initial dryout locations of the CANFLEX Mk-V bundle were mainly observed at the mid-spacer plane of either the $10^{th}$ (about $80\%$) or $11^{th}$ ($20\%$) bundle in the 12-bundle string, as compared to the mid-spacer and downstream-button planes for the CANFLEX Mk-IV bundle. Dryout power and boiling-length-average (BLA) CHF values exhibit consistent trends and little scatter with varying flow conditions for both types of CANFLEX bundles in uncrept and crept channels. An increase in pressure tube creep has led to a reduction in dryout power (about $20\%$ far the $3.3\%$ crept channel and $27\%$ for the $5.1\%$ crept channel as compared to dryout powers for the uncrept channel). Increasing the bearing pad height of the CANFLEX bundle has led to an increase in the dryout power. Overall, the dryout power of the CANFLEX Mk-V bundle is 7 to $10\%$ higher than that of the CANFLEX Mk-IV bundle at the inlet temperature range of interest (i.e., between 243 and $290^{\circ}C$).

• 마이크로전자및패키징학회지
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• 제8권4호
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• pp.1-10
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• 2001

유리 기판상에 증착된 패드(pad)의 접합부 가열에 의한 면배열(area array) 형태 선자 패키지의 chip-on-glass(COG) 마운팅 공정이 시도되었다. 패드는 접합층(즉, Cr 또는 Ti)과 상부 코팅층(즉, Ni 또는 Cu)으로 구성되었으며, 이 중 접합층이 유리 기판을 투과하는 UV레이저에 의해 가열되었다. 접합층에 흡수된 레이저 에너지는 열전노 과정을 통하여 패드와 물리적으로 접촉되어 있는 솔더볼의 온도를 상승시켰으며, 리플로우 과정을 통하여 솔더 범프를 형성하였다. 레이저 가열 동안 솔더볼의 온도 이력(profile)을 측정함으로써 레이저 리플로우 솔더링시 접합층 및 상부 코팅층의 영향이 조사되었다. 그 결과들은 접합층의 반사율 측정 견과에 기초하여 논의되었다. 아울러 솔더 범프의 미세구조와 기계적 특성이 조사되었다.