• Annals of Clinical Neurophysiology
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• v.13 no.2
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• pp.80-86
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• 2011

Background: A dry-type electrode is an alternative to the conventional wet-type electrode, because it can be applied without any skin preparation, such as a conductive electrolyte. However, because a dry-type electrode without electrolyte has high electrode-to-skin impedance, an impedance-converting amplifier is typically used to minimize the distortion of the bioelectric signal. In this study, we developed an active dry electroencephalography (EEG) electrode using an impedance converter, and compared its performance with a conventional Ag/AgCl EEG electrode. Methods: We developed an active dry electrode with an impedance converter using a chopper-stabilized operational amplifier. Two electrodes, a conventional Ag/AgCl electrode and our active electrode, were used to acquire EEG signals simultaneously, and the performance was tested in terms of (1) the electrode impedance, (2) raw data quality, and (3) the robustness of any artifacts. Results: The contact impedance of the developed electrode was lower than that of the Ag/AgCl electrode ($0.3{\pm}0.1$ vs. $2.7{\pm}0.7\;k{\Omega}$, respectively). The EEG signal and power spectrum were similar for both electrodes. Additionally, our electrode had a lower 60-Hz component than the Ag/AgCl electrode (16.64 vs. 24.33 dB, respectively). The change in potential of the developed electrode with a physical stimulus was lower than for the Ag/AgCl electrode ($58.7{\pm}30.6$ vs. $81.0{\pm}19.1\;{\mu}V$, respectively), and the difference was close to statistical significance (P=0.07). Conclusions: Our electrode can be used to replace Ag/AgCl electrodes, when EEG recording is emergently required, such as in emergency rooms or in intensive care units.

• Food Science and Preservation
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• v.14 no.3
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• pp.269-275
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• 2007

This paper was study to develop an extract of Elaeagnus multiflora as a beverage component, and was part of a broader research project for at the development of processed foods using extract of Elaeagnus multiflora. Acceptable mixing properties of the beverage were significantly related to brix values, pH, total acidity, and total phenol contents. When brown rice vinegar was used as a supplement, the vinegar contributed only 1% of total acidity content, and the brix was below 5% of acceptable level. Maximal total acidity of the mixed beverage was attained which added 19.2%(v/v) of Elaeagnus multiflora extract and 7.6%(v/v) of brown rice vinegar. The mixed beverage contributed 0.88% of the total acidity content. The maximum condition of brix(11.5) of the mixed beverage was arrived to 24.7%(v/v) of Elaeagnus multiflora extract and 4.9%(v/v) of brown rice vinegar. The maximum polyphenol contents of beverage(14.47 mg%) was achieved which added 25.0%(v/v) of Elaeagnus multiflora extract and 4.3%(v/v) of brown rice vinegar.

• Food Science and Preservation
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• v.17 no.6
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• pp.770-776
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• 2010

Sarcodon aspratus (Berk.) S. Ito is a wild mushroom commonly consumed in Korea due to its beneficial effects on health. However, only limited information on the volatile and nonvolatile constituents of S. aspratus is available. In the present study, the total concentration of mushroom soluble sugars, including glucose, trehalose, sucrose, and xylose, was found to be 202.5 mg/kg. The total contents of free and essential amino acids were 2,592.1 mg/kg and 1,249.5 mg/kg, respectively; arginine, lysine, methionine, and valine were the major amino acids present. The contents of total 5'-nucleotides and flavor 5'-nucleotides in S. aspratus were 2,510.7 mg/kg and 773.4 mg/kg, respectively. The volatile components of S. aspratus were collected by simultaneous distillation-extraction (SDE) and analyzed by gas chromatography-massspectrometry (GC-MS). A total of 27 volatile compounds were isolated and identified. The most abundant was l-octen-3-ol, which accounted for more than 68% of total volatiles; other important compounds were 2-octen-1-ol, 1-octen-3-one, and 2-octenol. Our results provide preliminary data for the development of S. aspratus as a food material.

• YAKHAK HOEJI
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• v.51 no.2
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• pp.96-102
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• 2007

Measurement of globotriaosylceramide (Gb3, ceramide trihexoside) in urine has clinical importance for monitoring after enzyme replacement therapy in Fabry disease patients. The disease is an X-linked lipid storage disorder that results from a deficiency of the enzyme ${\alpha}$-galactosidase A (${\alpha}$-Gal A). The lack of ${\alpha}$-Gal A causes an intracellular accumulation of glycosphingolipids, mainly Gb3. A simple, rapid, and highly sensitive analytical method for Gb3 in urine was developed without labor-extensive pre-treatment by electrospray ionization MS/MS (ESI-MS/MS). Only simple 5-fold dilution of urine is necessary for the extraction and isolation of Gb3 in urine. Gb3 in diluted urine was dissolved in dioxane containing C17:0 Gb3 as an internal standard. After centrifugation it was directly injected and analyzed through guard column by in combination with multiple reaction monitoring mode of ESI-MS/MS. Eight isoforms of Gb3 were completely resolved from urine matrix. C24:0 Gb3 occupied 50% of total Gb3 as a major component in urine. Linear relationship for Gb3 isoforms was found in the range of 0.005${\sim}$5.0 ${\mu}$g/ml. The limit of detection (S/N=5) was 0.005 ${\mu}$g/ml and limit of quantification was 0.05 ${\mu}$g/ml for C24:0 Gb3 with acceptable precision and accuracy. Correlation coefficient of calibration curves for 8 Gb3 isoforms ranged from 0.9598 to 0.9975. This method could be useful for rapid and sensitive 1st line Fabry disease screening, monitoring and/or diagnostic tool for Fabry disease.

• Journal of the Korean Geographical Society
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• v.42 no.6
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• pp.851-862
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• 2007

The main reason of environmental pollution and destruction due to an indiscreet development of spa is the law of spa in use. According to the law of spa, the water of spa is ordained not mineral component and its efficacy but water temperature of over $25^{\circ}C$. Therefore this research was to analyze the differences between traditional spa and newly-established spa based on heat flow, geological rock, and fault relating to spa in order to call attention to a revision of the law of spa. According to the results, the location of the traditional spas was in accord with places which are Pohang, Bugok, Dongrae and Haeundae-gu of Busan, Uljin, Chungju, Usung-gu of Daejeon, Yesan, Asan, and Ichon. The heat flow of these places is over 67mW/m2 that is an average of South Korea. Relating to a fault, 92.3% of the traditional spas concurs with a fault and 33.5% of newly-established spa is in accord with a fault. 58.2% of the traditional spas and 42.7% of the newly-established spa are consistent with the granite.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.4
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• pp.442-450
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• 2009

Piperine is an alkaloid-amine found in pepper and has been reported to have anticarcinogenic properties. To explore the possibility that piperine has cancer chemopreventive and chemotherapeutic effects in colon cancer, we examined whether piperine inhibits the growth of HT-29 human colon cancer cells and investigated the mechanisms for this effect. Cells were cultured with various concentrations ($0{\sim}40{\mu}M$) of piperine. Piperine decreased the cell viability and induced apoptosis of HT-29 cells. Western blot analysis of total cell lysates revealed that piperine decreases the protein levels of Bcl-2, Mcl-1, and intact Bid but increases Bik levels. Piperine increased the percentage of cells with depolarized mitochondrial membrane, and the release of cytochrome c into cytoplasm. Piperine induced the cleavage of poly (ADP-ribose) polymerase and caspases 8, 9, 7, and 3 and increased the Fas levels. In addition, piperine significantly decreased the protein levels of survivin. The present results indicate that piperine inhibits the growth of HT-29 colon cancer cells by the induction of apoptosis, which may be mediated by its ability to change the Bcl-2 family proteins, increase the activation of caspases, and decrease survivin levels. Overall, our findings suggest that piperine has cancer chemotherapeutic effects in colon cancer.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.4
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• pp.293-301
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• 2017

A Sub-kWe small-scale experimental test loop was manufactured to investigate characteristics of the supercritical carbon dioxide power cycle. A high-speed turbo-generator was also designed and manufactured. The designed rotational speed of this turbo-generator was 200,000 rpm. Because of the low expansion ratio through the turbine and low mass flowrate, the rotational speed of the turbo-generator was high. Therefore, it was difficult to select the rotating parts and design the turbine wheel, axial force balance and rotor dynamics in the lab-scale experimental test loop. Using only one channel of the nozzle, the partial admission method was adapted to reduce the rotational speed of the rotor. This was the world's first approach to the supercritical carbon dioxide turbo-generator. A cold-run test using nitrogen gas under an atmospheric condition was conducted to observe the effect of the partial admission nozzle on the rotor dynamics. The vibration level of the rotor was obtained using a gap sensor, and the results showed that the effect of the partial admission nozzle on the rotor dynamics was allowable.

• Journal of the Microelectronics and Packaging Society
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• v.16 no.1
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• pp.13-19
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• 2009

A 440MHz wireless and passive surface acoustic wave (SAW) based chemical sensor was developed on a $41^{\circ}YX\;LiNbO_3$ piezoelectric substrate for simultaneous measurement of $CO_2$ gas and relative humidity (RH) using a reflective delay line pattern as the sensor element. The reflective delay line is composed of an interdigital transducer (IDT) and several shorted grating reflectors. A Teflon AF 2400 and a hydrophilic $SiO_2$ layer were used as $CO_2$ and water vapor sensitive films. The coupling of mode (COM) modeling was conducted to determine optimal device parameters prior to fabrication. According to simulation results, the device was fabricated and then wirelessly measured using the network analyzer. The measured reflective coefficient $S_{11}$ in the time domain showed high signal/noise (S/N) ratio, small signal attenuation, and few spurious peaks. In the $CO_2$ and humidity testing, high sensitivity ($2^{\circ}/ppm$ for $CO_2$ detection and $7.45^{\circ}/%$RH for humidity sensing), good linearity and repeatability were observed in the $CO_2$ concentration ranges of $75{\sim}375ppm$ and humidity levels of $20{\sim}80%$RH. Temperature and humidity compensations were also investigated during the sensitivity evaluation process.

• Journal of Intelligence and Information Systems
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• v.16 no.2
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• pp.33-54
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• 2010

The World Wide Web is transitioning from being a mere collection of documents that contain useful information toward providing a collection of services that perform useful tasks. The emerging Web service technology has been envisioned as the next technological wave and is expected to play an important role in this recent transformation of the Web. By providing interoperable interface standards for application-to-application communication, Web services can be combined with component based software development to promote application interaction both within and across enterprises. To make Web services for service-oriented computing operational, it is important that Web service repositories not only be well-structured but also provide efficient tools for developers to find reusable Web service components that meet their needs. As the potential of Web services for service-oriented computing is being widely recognized, the demand for effective Web service discovery mechanisms is concomitantly growing. A number of public Web service repositories have been proposed, but the Web service taxonomy generation has not been satisfactorily addressed. Unfortunately, most existing Web service taxonomies are either too rudimentary to be useful or too hard to be maintained. In this paper, we propose a Web service taxonomy generation framework that combines an artificial neural network based clustering techniques with descriptive label generating and leverages the semantics of the XML-based service specification in WSDL documents. We believe that this is one of the first attempts at applying data mining techniques in the Web service discovery domain. We have developed a prototype system based on the proposed framework using an unsupervised artificial neural network and empirically evaluated the proposed approach and tool using real Web service descriptions drawn from operational Web service repositories. We report on some preliminary results demonstrating the efficacy of the proposed approach.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.171-174
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• 2005

According as marine leisure industry has developed and the demand of leisure culture has increased rapidly, a desire about service which supply marine safety and connect marine information is enlarging. The performance of personal mobile device has improved and been evolved by composition terminal. So, it became possible that storage and expression of multimedia information as well as simple communication facility. Domestic wireless internet has given development strain to developer and contents Provider(CP) because of different platform. And this has become hindrance factor of wireless internet activation. But, recently, the use of WIPI(Wireless Internet Platform for Interoperability), the wireless internet standard platform, could use different wireless application programs and also guarantee the independency for hardware. We wish to develop contents of download form that supply geographic information of Electronic Navigational Chart(ENC) in the marine that is digitalized to carrying along terminal of WIPI base and various informations for marine leisure. For this, DB that offer ENC and additional information should be constructed. Also, we need server (CPS; Contents provider Server) that offer required contents. In this paper, we design web retrieval agent which store request information to database. When consumer required necessary information through personal mobile device, CPS can inform that by real time. So, we wish to develop agent component that parse informations in various World Wide Webs, and store to database.