• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.11
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• pp.44-52
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• 2011

In this article, we present a QoS-guaranteed IP mobility management scheme of Internet service for fast moving vehicles with multiple wireless network interfaces. The idea of the proposed mechanism consists of two things. One is that new wireless connections are established to available wireless channels whenever the measured data rate at the vehicle equipped with mobile gateway drops below to the required data rate of the user requirement. The other is that parallel distribution packet tunnels between an access router and the mobile gateway are dynamically constructed using multiple wireless network interfaces in order to guarantee the required data rate during the mobile gateway's movement. By doing these methods, the required data rate of the mobile gateway can be preserved while eliminating the possible delay and packet loss during handover operation, thus resulting in the guaranteed QoS. The architecture of the IETF standard HMIPv6 has been extended to realize the proposed scheme, and detailed algorithms for the extension of HMIPv6 has been designed. Finally, simulation has been done for performance evaluation, and the simulation results show that the proposed mechanism demonstrates guaranteed QoS during the handover with regard to the handover delay, packet loss and throughput.

• Journal of Technologic Dentistry
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• v.36 no.4
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• pp.277-296
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• 2014

Purpose: This study intends to set standard for organizing the curriculum of short-term dental technicians and the change of job environment, as well as the knowledge & training, by identifying the importance and actual job performance of dental technicians following job analysis in the university education of Dept. of Dental Laboratory Technology, and furthermore to foster junior executives to cope with modernization and globalization. Methods: The tools used in this study are based on the job analysis of research report suggested by National Health Personnel Licensing Examination Board(Lee Gyu-seon, 2011), and it consists of general characteristic 7 items. Every competence duty was measured through Likert 5 point gauging, and internal consistency through Cronbach's Alpha. The competence importance of entire questionnaire was .984 and its performance was .874, reflecting considerably high level, and in terms of each competence duty, high credibility was proved and high internal consistency was verified with competence importance ranging from the minimum .655 to the maximum .966 and its performance ranging from the minimum .677 to the maximum .993. Results: Competence importance and its performance in each duty on the job analysis of dental technicians were measured. In competence importance in each duty, the highest was "checking design order form"(average, 4.52), followed by "selling dental prosthesis"(average 4.49), "making removable orthodontic appliance"(average, 4.48), "open managing dental laboratory"(average, 4.46) in order. However, "making complete denture" was found the lowest(average, 4.23), with importance of all competence dutys was considerably high level. In the performance of its competence duty, "checking design order form"(average, 4.04) was found to be the most importance competence, followed by "making conservative restoration"(average, 4.00), "making porcelain"(average 3.98), "checking working cast"(average, 3.90) in order. However it was found out that "making fixed orthodontic appliance"(average, 3.12) was the lowest, and the importance of all competence dutys was quite high level. Conclusion: The duties of dental technicians consist of 13 kinds, in total, and it was found out that "checking design order form"(average, 4.52) was the most important in the competence importance and job performance. In particular, it was revealed that there was a great difference between the competence importance and its performance in the order of "selling dental prosthesis", "open managing dental laboratory", "making removable orthodontic appliance", "making CAD/CAM prosthesis", and then "making fixed orthodontic appliance".

• Journal of Yeungnam Medical Science
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• v.2 no.1
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• pp.229-235
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• 1985

This study was undertaken for the clinical evaluation and statistical analysis on the 88 women with histopathologically confirmed ectopic pregnancies who were admitted and treated from grand opening on May-28, 1983 to Sept.-30, 1985. Incidence of ectopic pregnancy was 1 in 22.2 deliveries and the most common age group was in 30~34 years of age. There was tendency of decreasing incidencies as the gravidity, panty or artificial abortion were over 3. The most common etiologic factor was pelvic inflammatory disease and procedures for family planning were the next common. Common symptoms were lower abdominal pain (85.2%) and vaginal spotting (56.8%). At the admission, hemoglobin level under 10gm% were 44.3%, 69.5% of urine HCG tests were positive. Culdocentesis was positive only in 75.9%. Termination was frequent at 6 ~ 7 weeks of gestation mostly with rupture or abortion. Free blood in the abdominal cavity was averaged 1,224 ml. 4 cases of clinicobiochemically suspected ectopic pregnancies with spontaneous regression were excluded, and there was no fatal case treated in hospital.

• Publications of The Korean Astronomical Society
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• v.27 no.3
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• pp.49-59
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• 2012

KASI (Korea Astronomy and Space Science Institute) has developed an SLR (Satellite Laser Ranging) system since 2008. The name of the development program is ARGO (Accurate Ranging system for Geodetic Observation). ARGO has a wide range of applications in the satellite precise orbit determination and space geodesy research using SLR with mm-level accuracy. ARGO-M (Mobile, bistatic 10 cm transmitting/40 cm receiving telescopes) and ARGO-F (Fixed stationary, about 1 m transmitting/receiving integrated telescope) SLR systems development will be completed by 2014. In 2011, ARGO-M system integration was completed. At present ARGO-M is in the course of system calibration, functionality, and performance tests. It consists of six subsystems, OPS (Optics System), TMS (Tracking Mount System), OES (Opto-Electronic System), CDS (Container-Dome System), LAS (Laser System) and AOS (ARGO Operation System). In this paper, ARGO-M system structure and integration status are introduced and described.

• Polymer(Korea)
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• v.33 no.4
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• pp.389-395
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• 2009

To develop the carrier of hydrophobic antifungal agents based on low molecular weight water-soluble chitosan (LMWSC), LMWSC was chemically modified with deoxycholic acid (DA) which is one of the bile acid as a hydrophobic group. The nanoparticles (WSCDA) using DA conjugated LMWSC were characterized using dynamic light scattering (DLS) and transmittance electron microscope (TEM). The particle size of WSCDA ranged from 250 to 350 nm and increased with the number of DA substitution. The loaded itraconazole as an antifungal agent WSCDA nanoparticles (WSCDA-ITCN) were prepared by solvent evaporation method. The drug content and the loading efficiency were investigated approximately $9{\sim}10%$ and $61{\sim}68%$ by UV spectrophotometer, respectively. The release of drug from nanoparticles was slow and showed sustained release characteristics. Based on the results of release study that the higher DA contents in WSCDA, the slower the releasing rate, the WSCDA-ITCN could be used as an excellent antifungal agent.

• Polymer(Korea)
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• v.37 no.1
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• pp.61-65
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• 2013

In this work, the anodic oxidation of carbon fibers was carried out to enhance the mechanical interfacial properties of carbon fibers-reinforced epoxy matrix composites. The surface characteristics of the carbon fibers were studied by FTIR, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). Also, the mechanical interfacial properties of the composites were studied with interlaminar shear strength (ILSS), critical stress intensity factor ($K_{IC}$), and critical strain energy release rate ($G_{IC}$). The anodic oxidation led to a significant change in the surface characteristics of the carbon fibers. The anodic oxidation of carbon fiber improved the mechanical interfacial properties, such as ILSS, $K_{IC}$, and $G_{IC}$ of the composites. The mechanical interfacial properties of the composites anodized at 20% sulfuric/nitric (3/1) were the highest values among the anodized carbon fibers. These results were attributed to the increase of the degree of adhesion at interfaces between the carbon fibers and the matrix resins in the composite systems.

• Elastomers and Composites
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• v.47 no.4
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• pp.297-309
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• 2012

Different amounts of foaming agents were employed in natural rubber(NR)/butadiene rubber(BR) blends to understand the foaming behavior in presence of nano-reinforcing agent, zinc methacrylate (ZMA). The ZMA greatly improved most of the mechanical properties of the rubber foams, however it did not show considerable effect on the cell morphology, such as cell size, density and porosity. It was also observed that the foaming agent concentration affected all the mechanical parameters. When the content of foaming agent was increased, the number of foams was increased leading to a decrease in density of the compounds. But the size and distribution of foams remained unchanged with increased foaming agent. The effect of high styrene-butadiene rubber (HSBR) was also studied. The size of cells became smaller and the cell uniformity was improved with increasing HSBR. The foam rubber compounds showed much efficient energy absorbing capability at higher strains.

• Archives of Pharmacal Research
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• v.28 no.4
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• pp.413-420
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• 2005

We previously demonstrated the ability of ginseng saponins (active ingredients of Panax ginseng) to enhance $Ca^{2+}$-activated $Cl^{-}$ current. The mechanism for this ginseng saponin-induced enhancement was proposed to be the release of $Ca^{2+}$ from $IP_{3}-sensitive$ intracellular stores through the activation of PTX-insensitive $G\alpha_{q/11}$ proteins and PLC pathway. Recent studies have shown that calmodulin (CaM) regulates $IP_{3}$ receptor-mediated $Ca^{2+}$ release in both $Ca^{2+}-dependent$ and -independent manner. In the present study, we have investigated the effects of CaM on ginseng saponin-induced $Ca^{2+}$-activated $Cl^{-}$ current responses in Xenopus oocytes. Intraoocyte injection of CaM inhibited ginseng saponin-induced $Ca^{2+}$-activated $Cl^{-}$ current enhancement, whereas co-injection of calmidazolium, a CaM antagonist, with CaM blocked CaM action. The inhibitory effect of CaM on ginseng saponin-induced $Ca^{2+}$-activated $Cl^{-}$ current enhancement was dose- and time-dependent, with an $IC_{50} of 14.9\pm3.5 {\mu}M$. The inhibitory effect of CaM on saponin's activity was maximal after 6 h of intraoocyte injection of CaM, and after 48 h the activity of saponin recovered to control level. The half-recovery time was calculated to be $16.7\pm4.3 h$. Intraoocyte injection of CaM inhibited $Ca^{2+}$-induced $Ca^{2+}$-activated $Cl^{-}$ current enhancement and also attenuated $IP_{3}$-induced $Ca^{2+}$-activated $Cl^{-}$ current enhancement. $Ca^{2+}$/CaM kinase II inhibitor did not inhibit CaM-caused attenuation of ginseng saponin-induced $Ca^{2+}$-activated $Cl^{-}$ current enhancement. These results suggest that CaM regulates ginseng saponin effect on $Ca^{2+}$-activated $Cl^{-}$ current enhancement via $Ca^{2+}$-independent manner.

• The Korean Journal of Physiology
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• v.30 no.1
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• pp.33-41
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• 1996

The present study was aimed to investigate the role of endothelium-derived nitric oxide (NO) in the control of renin release and to examine if NO is implicated in the development of two-kidney, one clip (2K1C) hypertension. Male Sprague-Dawley rats $(150{\sim}200\; g)$ were constricted at the left renal artery. They were then supplemented with $N^{G}-nitro-L-arginine\;methyl\;ester\;(L-NAME,\; 5mg/100\;mL)$ or with L-arginine hydrochloride (400 mg/100 mL) in the drinking water. The control group was supplied with normal tap water. The sham-clipped rats were operated as in 2K1C rats except for that no clip was made. The kidneys were taken to examine in vitro release of renin at days 7 and 14 following clipping the renal artery. Northern blot analysis was also done to assess the expression of renin gene in the kidney. In sham-clipped rats, L-NAME caused a sustained increase of the blood pressure, whereas L-arginine was without effect. Neither L-NAME nor L-arginine-supplementation significantly affected the development of hypertension in 2K1C rats. Plasma renin concentration (PRC) measured on day 28 did not significantly differ among the L-NAME, L-arginine and control groups either in 2K1C or in sham-clipped rats. Renin contents (RRC) in the clipped kidney were increased, while those in the contralateral kidney were decreased. The release of renin in vitro from cortical slices was also enhanced in the clipped kidney, whereas it was attenuated in the contralateral. Comparing the RRC and in vitro release, the latter was more rapidly decreased than the former in the contralateral kidney. The renin mRNA levels in the contralateral kidney were almost at their nadir at days 7 and 14 in 2K1C rats. It is suggested that NO does not affect the development of 2K1C hypertension in which the renin-angiotensin system has been activated. The data also confirm that RRC and renin gene expression are increased in the clipped kidney and suppressed in the contralateral kidney in 2K1C rats.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.3B
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• pp.275-286
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• 2011

As the 21st century paradigm of healthcare service changes from post-therapeutic treatment to disease prevention and management in advance, the M2M-based u-healthcare application service is increasingly important. M2M-based u-healthcare application service uses mobile handsets equipped with sensors to measure vital information, and the medical staff in remote locations can manage the health of the patient or the public in real time. In this paper, IEEE/HL7 translation gateway, utilizing the gateway based on M2M u-healthcare application service structure, which is based on international standards, has been designed and implemented. Specifically, the gateway between ISO/IEEE 11073 standards and ANSI HL7 has been developed. The former defines the protocol for the exchange of information between the agent device and the manger devices for measuring and handling biological signal, and the latter defines the application layer protocol for the exchange of various healthcare information systems. Finally, in order to demonstrate the functionality of the proposed architecture, the M2M-based U-healthcare application service based on IEEE/HL7 translation gateway, utilizing the gateway, has been developed which can measure, collect and process a variety of vital signs such as ECG or SpO2.