• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2000.04a
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• pp.73-73
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• 2000

Shear strength of BGA solder joints on Cu pad was studied for Cu-contained Sn n.5 a and 2.5wt.% Cu) and Sn-Pb (o.5wt.% Cu) solders, with emphasis on the roles of the C Cu-Sn intermetallic layer thickness and the roughness of the interface between the i intermetallic layer and solder. The shear strength test was performed both for a as-soldered s이der joints with soldering reaction times of 1, 2, 4 min and for aged s이der j joints at 170 C up to 16 days. The Cu addition to both pure Sn and eutectic Sn-Pb s solders increased the intermetallic layer thickness at both soldering and aging t temperatures. The Cu addition also resulted in changes in the roughness of the interface b between the intermetallic layer and solder at as-soldered states. With increasing Cu c content. the interface roughened for Sn-Cu solders whereas it flattened for Sn-Pb-Cu s solders. The shear fractures in all solder joints investigated were confined in the bulk s solder rather than through the intermetallic layer. Therefore, the effect of Cu content in s solders on the shear strength of the solder joints was primarily attributed to its i influence on the micros$\sigma$ucture of bulk solder, such as the size and spatial distributions of CU6Sn5 precipitates. In addition, the critical intermetallic layer thickness for a m maximum shear strength seemed to depend on the Cu content in bulk solder.older.

• Journal of Internet Computing and Services
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• v.14 no.3
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• pp.1-13
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• 2013

The recent emergence of diverse platform-based media devices such as smart phones and iPads has aroused interest of consumers all across the world. This interest has led to digitalization of paper books and a steep growth in the digital publishing industry at home and abroad. However, advent of various devices and content has caused the issue of compatibility and produced needs and demand for standardization to exchange and share content related to digital publication. Through collection of opinions of 16 stakeholders from the industrial, academic, research, and public sectors, this study aims to examine predictable future changes about content and its distribution, devices, standardization, technical protective measures, and obstacles in future digital publishing and eventually to draw out areas and elements for future standards development.

• Ocean and Polar Research
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• v.38 no.2
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• pp.129-137
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• 2016

This study aimed to isolate and characterize sulfated polysaccharides (SPs) from Iridaea cordata and evaluate their anticancer activity. SPs of the Antarctic red seaweed were obtained by $CaCl_2$ (SP1) and ethanol precipitations (SP2) following diluted acid extraction at room temperature. Yields of SP1 and SP2 were approximately 14% and 23%, respectively, of the dry weight of red seaweed. The average molecular mass of the SP1 and SP2 was estimated about $1.84{\times}10^3$ and $1.42{\times}10^3kDa$, respectively, by size-fractionation High-Performance Liquid Chromatography (HPLC). From the High-Performance Anion-Exchange Chromatography-Pulsed Amperometric Detection (HPAEC-PAD) analysis, the main monosaccharide was galactose with glucose and fucose as minor components. The sulfate content of SP2 (40.4%) was slightly higher than that of SP1 (33.8%). The FT-IR spectra also showed characteristic band of carrageenan-like sulfated polysaccharides. Taken together the SPs are thought to be carrageenan-like sulfated galactan. The polysaccharides (SPs) from I. cordata exhibited weak antitumor activity against PC-3 (prostate cancer), HeLa (cervical cancer), and HT-29 (human colon adenocarcinoma). To our knowledge, this is the first data on biological activity of the Antarctic red seaweed I. cordata.

• International Journal of Knowledge Content Development & Technology
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• v.7 no.3
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• pp.67-86
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• 2017

The emergence of smart devices such as smartphones (e.g., iPhone) and tablets (e.g., iPad) may enhance e-learning by increasing communication and collaborative learning outside the classroom. These devices also facilitate the use of online technologies such as Facebook. However, the adaptation of Learning Management System (LMS) services to mobile devices took longer than social networks or online tools such as Facebook and Twitter have already been long used via smartphone. The main purposes of this study are to explore students' skill levels of LMS (Moodle) and their knowledge of online tools or technologies and then examine if there is a correlation between smartphone use and using of online tools and Moodle in learning. The study conducted among 173 students in the Department of Information Studies (DIS) in Oman, using online survey. The study found that most students demonstrated high levels of accessing course/subject materials and regularly engaging with studies of using LMSs. YouTube, Wikipedia and Facebook were clearly recorded as the most popular sites among students while LinkedIn and Academia.edu were two online tools that had never been heard of by over half of the 142 participants. Emailing and searching are recorded the most popular online learning activities among students. The study concluded that students prefer to use smartphone for accessing these tools rather than using it to access LMSs, while a positive correlation was found between the use of these tools and smartphones, but there was no correlation between smartphones and using LMSs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.1
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• pp.316-322
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• 2014

The present study investigated the inflammatory hypersensitivity following activation of the transient receptor potential vanilloid receptor-1(TRPV1) in rats. Experiments were carried out on male Sprague-Dawley rats weighing 220-260g. Following an subcutaneous injection of 5% formalin in the orofacial area, nociceptive scratching behavior was recorded for 9 successive 5-min intervals in rats. The subcutaneous injection of $25{\mu}L$ of 5% formalin produced noxious scratching behavior. Injection of capsaicin, TRPV1 agonist, alone into the vibrissa pad did not produced nociceptive behavior. After subcutaneous injection of capsaicin(0$0.1{\mu}g$, $1{\mu}g/10{\mu}L$) in the formalin-treated rats, nociceptive scratching behavior was recorded for 9 successive 5-min internals. Injection of capsaicin into the vibrissa pad significantly increased the number of scratches at 1 hours after injection. Noxious behavioral responses induced by subcutaneous capsaicin injection were significantly potentiated in formalin-treated rats. Pre or post-treatment with iodo-resinaferatoxin(IRTX), TRPV1 antagonist, significantly attenuated increased nociceptive behavior. These findings suggest that activation of the TRPV1 enhanced formalin-induced inflammatory pain in the orofacial area of rats.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.2
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• pp.419-426
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• 2004

This experimental study was designed to investigate the effects of Yukgunja-tang(YGJT) on the inhibition of cerebral ischemia in rats. And We measured regional cerebral blood f1ow(rCBF) and pial arterial diameter(PAD) in cerebral ischemic rats, and cytokines production in serum Of cerebral ischemic rats. The results were as follows; Both rCBF and PAD were significantly and stably increased by YGJT(10 mg/kg, i.p.) during the period of cerebral reperfusion, which contrasted with the findings of rapid and marked increase in control group. In cytokine production of serum by drawing from femoral arterial blood after middle cerebral arterial occlusion(MCAO) 1 hr, IL-1β and TGF-β production of sample group were similar to that of control group, but sample group was decreased TNF-α production compared with control group, and was significantly increased IL-10 production in compared with control group. In cytokine production of serum by drawing from femoral arterial blood after reperfusion 1 hr, sample group was significantly decreased IL-1β and TNF-α production compared with control group, but TGF-β production of sample group was similar to that of control group, and sample group was significantly increased IL-10 production compared with control group. In cytokine production of serum by drawing from femoral arterial blood after reperfusion 4 hrs, sample group was significantly decreased IL-1β production compared with control group, and sample group was decreased TNF-α production in compared with control group, but TGF-β production of sample group was similar to that of control group, and sample group was increased IL-10 production compared with control group. This results were suggested that YGJT has inhibitive effect on the brain damage by inhibited IL-1β production and TNF-α production, but accelerated IL-10 production. We thought that YGJT should have an anti-ischemic effect through the improvement of cerebral hemodynamics and inhibitive effect on the brain damage.

• International Journal of Oral Biology
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• v.34 no.1
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• pp.1-6
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• 2009

The purpose of the present study was to examine the role of peripheral nitric oxide (NO) pathways in the onset of interleukin (IL)-1$\beta$-induced mechanical allodynia in the orofacial area. Experiments were carried out on male Sprague-Dawley rats weighing 230-280 gm and surgical procedures were performed under pentobarbital sodium (40 mg/kg, i.p.). Under anesthesia, a polyethylene tube (PE10) was implanted into the subcutaneous area of one vibrissa pad, which enabled the injection of IL-1$\beta$ or other chemicals. We subcutaneously injected 50 ${\mu}L$ of IL-1$\beta$ into a vibrissa pad through the implanted polyethylene tube with a 100 ${\mu}L$ Hamilton syringe. After the administration of 0.01, 0.1, 1, or 10 pg of IL-1$\beta$, withdrawal behavioral responses were examined. The subcutaneous injection of saline had no effects on the air-puff thresholds. Following the subcutaneous injection of 0.01, 0.1, 1, or 10 pg of IL-1$\beta$, the threshold of air puffs decreased significantly to 12 $\pm$ 3, 7 $\pm$ 2, 5 $\pm$ 1, or 5 $\pm$ 1 psi, respectively, in a dose dependent manner. Pretreatment with L-NAME, a nitric oxide synthase (NOS) inhibitor, blocked IL-1$\beta$-induced mechanical allodynia. However, neither D-NAME, an inactive isomer of L-NAME, nor vehicle affected the IL-1$\beta$-induced mechanical allodynia. Subcutaneous injection of IL-1$\beta$ increased the number of c-fos-like immunoreactive neurons, whereas pretreatment with L-NAME decreased this number, in the trigeminal caudal nucleus. These results suggest that pro-inflammatory cytokines and NO are important contributors to the pathogenesis of persistent and exaggerated IL-1$\beta$-induced pain states. Based on these observations, peripheral application of NOS inhibitors may be of therapeutic value in treating pain disorders in the clinic.

• Journal of the Microelectronics and Packaging Society
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• v.30 no.3
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• pp.40-50
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• 2023

Recently, the number of components of smartphones increases rapidly, while the PCB size continuously decreases. Therefore, 3D technology with a stacked PCB has been developed to improve component density in smartphone. For the s tacked PCB, it i s very important to obtain solder bonding quality between PCBs. We investigated the effects of the properties, thickness, and number of layers of interposer PCB and sub PCB on warpage of PCB through experimental and numerical analysis to improve the reliability of the stacked PCB. The warpage of the interposer PCB decreased as the thermal expansion coefficient (CTE) of the prepreg decreased, and decreased as the glass transition temperature (Tg) increased. However, if temperature is 240℃ or higher, the reduction of warpage is not large. As FR-5 was applied, the warpage decreased more compared to FR-4, and the higher the number and thickness of the prepreg, the lower the warpage. For sub PCB, the CTE was more important for warpage than Tg of the prepreg, and increase in prepreg thickness was more effective in reducing the warpage. The shear tests indicated that the dummy pad design increased bonding strength. The tumble tests indicated that crack occurrence rate was greatly reduced with the dummy pad.

• Journal of Acupuncture Research
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• v.24 no.2
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• pp.141-153
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• 2007

Objectives: The purpose of this report is to examine the effect of $BL_{66}$ ${\cdot}$ $GB_{43}$ supplement and LIl ${\cdot}$ $GB_{44}$ draining in acupuncture for cerebral apoplexy treatment. Methods : I designed to investigate whether $BL_{66}$ ${\cdot}$ $GB_{43}$ supplement and $LI_1$ ${\cdot}$ $GB_{44}$ draining in acupuncture affects cerebral hemodynamics [regional cerebral blood flow(rCBF), mean arterial blood pressure(MABP)] in normal rats, and to make manifest whether $BL_{66}$ ${\cdot}$ $GB_{43}$ supplement and $LI_1$ ${\cdot}$ $GB_{44}$ draining in acupuncture is mediated by cyclooxygenase or guanylate cyclase. The changes of rCBF and MABP were determinated by laser-doppler flowmetry(LDF). Results : 1. $BL_{66}$ ${\cdot}$ $GB_{43}$ supplement and LI1 ${\cdot}$ $GB_{44}$ draining in acupuncture increased rCBF significantly, but decreased MABP. These results suggest that $BL_{66}$ ${\cdot}$ $GB_{43}$ supplement and $LI_1$ ${\cdot}$ $GB_{44}$ draining in acupuncture increased significantly rCBF by dilating pial arterial diameter(PAD). 2. By pretreatment with indomethacin(1 mg/kg, i.p.), the effect of $BL_{66}$ ${\cdot}$ $GB_{43}$ supplement and $LI_1$ ${\cdot}$ $GB_{44}$ draining in acupuncture induced increase of rCBF was significantly inhibited, the decreased MABP by treatment with $BL_{66}$ ${\cdot}$ $GB_{43}$ supplement and $LI_1$ ${\cdot}$ $GB_{44}$ draining in acupuncture was increased. 3. By pretreatment with methylene blue($10{\mu}/kg$, i.p.), the increased rCBF by treatment with $BL_{66}$ ${\cdot}$ $GB_{43}$ supplement and $LI_1$ ${\cdot}$ $GB_{44}$ draining in acupuncture was decreased conversely, the decreased MABP by treatment with $BL_{66}$ ${\cdot}$ $GB_{43}$ supplement and $LI_1$ ${\cdot}$ $GB_{44}$ draining in acupuncture was decreased. and then increased. Conclusion : I suggest that $BL_{66}$ ${\cdot}$ $GB_43$ supplement and $LI_1$ ${\cdot}$ $GB_{44}$ draining in acupuncture has an anti-ischemic effect through the improvement of cerebral hemodynamics.

• Archives of design research
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• v.18 no.4 s.62
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• pp.129-138
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• 2005

Until the early part of the 1990s, interior design has never been thought important by car makers. Repeated attempts have been made to systemize a technical structure, such as layout, driving method, and size, and the car's interior design has been developed by in simple comparison with the exterior design. In the 1990s, however, this trend began to change because consumers began spending more time in their cars, so the motive of the technology development became that of giving comfort and functional satisfaction to the customers. Observing how a person spends inside his or her car and considering the latest trends in car interiors have made a consumer-oriented sense of value i.e., intensifying the personality of the car's interior design and considering the emotional makeup of the consumer factor in the acquisition of a strategic brand identity. These days, car interiors assume a new concept every year due to the constant change in various factors, and the application of a high-tech design, with a sensing function and a navigation system, to achieve driverless running, is being raised as a key trend element technology for the future. Now, at the present when multilateral concept applications of design are attempted under the direct influences from other fields such as product design, fashion and furniture, I would like to lay stress on investigating and analysing the changes in car interior design varying with the background of the times and formative characteristics from the object point of view. On this study, I would like to compare the background of the times and flow of car interior design with priority given to crash pad and would like to attempt to present the direction of the future car interior design together with diversifying major technical factors.