• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.495-508
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• 2010

Vertical drains are commonly used to accelerate the consolidation process of soft soils, such as dredged materials. The installation of vertical drain provides a radial drainage path to water in the deposit soil in addition to the vertical direction. An estimation of time rate of settlement is considerably complicated when vertical drains are installed to enhance consolidation process of dredged material because the vertical drains are commonly installed before self-weight consolidation is ceased. In this paper, the vertical drain theory developed by Barron(1948) is applied to analyze the non-linear consolidation behavior considering radial drainage. The overall average degree of self-weight consolidation of the dredged soil under the condition that the water is drained in both radial and vertical directions is estimated using the Carillo(1942) formula. In addition, the Morris(2002) theory and the one-dimensional non-linear finite strain numerical model, PSDDF, are applied to analyze the self-weight consolidation in case of only the vertical drainage is considered. The new analysis approach proposed herein can simulate properly the time rate of the self-weight consolidation of dredged materials that is facilitated with vertical drains.

• Journal of the Korean Ceramic Society
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• v.33 no.5
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• pp.507-513
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• 1996

Nonlinear optical properties of TeO2-PbO-GeO2 glasses were investigated and their correlation with struc-tural modification was investigated. Third-order nonlinear susceptibility $\chi$, ranged between 5.0$\times$10-13 esu and 10.7$\times$10-13 esu which are approximately 20-40 times larger than that of silica glass. The glass with a composition of 85(80TeO2-20PbO)-15GeO2(mol%) seemed to provide an optimum compromise between $\chi$and the stability against crystallization. Analyses of the Raman spectra suggested that these glasses are mainly composed of [TeO4] tbp, [TeO3]tp and [GeO4] tetrahedral structural units. It was concluded that the positive contribution of Pb2+ with high polarizability to $\chi$ in TeO2-PbO glasses overwhelmed the negative influence due to the structural modification of [TeO4]tbplongrightarrow[TeO3]tp. On the other hand addition of GeO2 in TeO2-PbO-GeO2 glasses resulted in the decrease of $\chi$ values. This behavior was attributed to the formation of [GeO4] polyhedra at the expense of [TeOn] polyhedra and Pb2+ ions which normally sowed a higher contribu-tion to $\chi$ than [GeO4] polyhedra.

• Journal of Periodontal and Implant Science
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• v.27 no.2
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• pp.411-424
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• 1997

The purpose of this study was to evaluate in vitro the effects during subgingival calculus removal using Nd:YAG laser. The study group was consisted of 30 teeth with advanced periodontal disease extracted before the start of periodontal therapy. The specimens were divided into 8 different groups : 1) untreated control 2) scaling and root planing only 3) laser treated using 150mJ/pulse, 1sec, 5sec, contact mode 4) laser treated using 200mJ/pulse, 5sec, contact mode 5) laser treated using 150mJ/pulse, 1sec, non-contact mode 6) laser treated using 200mJ/pulse, 5sec, non-contact mode 7) laser treated using l5OmJ/pulse, 1sec, contact mode with water irrigation 8) laser treated using 200mJ/pulse, 5sec, contact mode with water irrigation. All specimens were prepared for evaluation by scanning electron microscopy(SEM). Specimens from Group 2 exhibited a smear layer of scale like texture with parallel instrument tracks resulting from curet use. Specimens treated by contact mode, Group 3 and 4 featured surface changes not observed· in controls such as charring, randomly distributed pitting and crater formation, and melting down of the tooth material and calculus. Specimens treated by noncontact mode, Group 5 and 6 featured similar surface changes observed in contact mode. However, the differences between contact and non-contact groups not significant. Specimens treated by contact mode with water irrigation, Group 7 and 8 featured slight surface change compared to other groups. The results suggested that Nd: YAG laser did not completely remove the subgingival calculus but was possible the application as adjunctive method.

• Journal of Advanced Marine Engineering and Technology
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• v.28 no.2
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• pp.300-308
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• 2004

The formation mechanism of anodic oxide films on Mg alloys when anodized in NaOH solution. was investigated by focusing on the effects of anodizing potential. Al content. and anodizing time. Pure Mg and Mg-Al alloys were anodized for 10 min at various potentials in NaOH solutions. $Mg(OH)_2$ was generated by an active dissolution reaction at the surface. and the product was affected by temperature. The intensity ratio of $Mg(OH)_2$ in the XRD analysis decreased with increasing applied potential. while that of MgO increased. The anti-corrosion properties of anodized specimens at each constant potential were better than those of non-anodized specimens. The specimen anodized at an applied potential of 3 V had the best anti-corrosion property. And the intensity ratio of $Mg_{17}Al_{12}$/Mg increased with aluminum content in Mg-Al alloys. During anodizing. the active dissolution reaction occurred preferentially in ${\beta}\;phase(Mg_{17}Al_{12})$ until about 4 mins. and then the current density increased radually until 7 mins. The dissolution reaction progressed in a phase(Mg) which not formed the intermetallic compound. which had a lower Al content. In the anodic polarization test of $0.017\;mol{\cdot}dm^-3$ NaCl and $0.1\;mol{\cdot}dm^-3\;Na_2SO_4$ at 298 K. the current density of Mg-15 mass% Al alloy anodized for 10 mins increased. since the anodic film that forms on the a phase is a non-compacted film. The anodic film on the phase for 30 mins was a compact film as compared with that for 10 mins.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.3
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• pp.761-766
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• 2012

Objective: Although various human cancer stem cells (CSCs) have been defined, their applications are restricted to immunocompromised models. Developing a novel CSC model which could be used in immunocompetent or transgenic mice is essential for further understanding of the biomolecular characteristics of tumor stem cells. Therefore, in this study, we analyzed murine lung cancer cells for the presence of CSCs. Methods: Side population (SP) cells were isolated by fluorescence activated cell sorting, followed by serum-free medium (SFM) culture, using Lewis lung carcinoma cell (LLC) line. The self-renewal, differentiated progeny, chemosensitivity, and tumorigenic properties in SP and non-SP cells were investigated through in vitro culture and in vivo serial transplantation. Differential expression profiles of stem cell markers were examined by RT-PCR. Results: The SP cell fraction comprised 1.1% of the total LLC population. SP cells were available to grow in SFM, and had significantly enhanced capacity for cell proliferation and colony formation. They were also more resistant to cisplatin in comparison to non-SP cells, and displayed increased tumorigenic ability. Moreover, SP cells showed higher mRNA expression of Oct-4, ABCG2, and CD44. Conclusion: We identified SP cells from a murine lung carcinoma, which possess well-known characteristics of CSCs. Our study established a useful model that should allow investigation of the biological features and pharmacosensitivity of lung CSCs, both in vitro and in syngeneic immunocompetent or transgenic/knockout mice.

• CELLMED
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• v.3 no.1
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• pp.9.1-9.10
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• 2013

In traditional systems of medicine including homeopathy, the Condurango extract (Con) is often used to cure stomach cancer mainly, without having any scientific validation of its anti-cancer ability. Con has therefore been tested against non-small-cell lung cancer cells (NSCLC) A549 and NCI-H522 (H522) known to contain the KRAS mutation, making them resistant to most chemotherapeutic agents. As cancer cells generally defy cytotoxicity developed by chemopreventive agents and escape cell death, any drug showing the capability of preferentially killing cancer cells through apoptosis is worth consideration for judicious application. A549 and H522 cells were exposed to $0.35{\mu}g/{\mu}l$ and $0.25{\mu}g/{\mu}l$ of Con, respectively, for 48 h and analysed based on various protocols associated with apoptosis and DNA damage, such as MTT assay to determine cell viability, LDH assay, DNA fragmentation assay, comet assay, and microscopical examinations of DNA binding fluorescence stains like DAPI, Hoechst 33258 and acridine orange/ethidium bromide to determine the extent of DNA damage made in drug-treated and untreated cells and the results compared. Changes in mitochondrial membrane potential and the generation of reactive oxygen species were also documented through standard techniques. Con killed almost 50% of the cancer cells but spared normal cells significantly. Fluorescence studies revealed increased DNA nick formation and depolarized membrane potentials after drug treatment in both cell types. Caspase-3 expression levels confirmed the apoptosis-inducing potential of Con in both the NSCLC lines. Thus, overall results suggest considerable anticancer potential of Con against NSCLC in vitro, validating its use against lung cancer by practitioners of traditional medicine including homeopathy.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.1033-1036
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• 2002

Wafer bonding methods such as fusion and anodic bonding suffer from high temperature treatment, long processing time, and possible damage to the micro-scale sensor or actuators. In the localized bonding process, beating was conducted locally while the whole wafer is maintained at a relatively low temperature. But previous research of localized heating has some problems, such as non-uniform soldering due to non-uniform heating and micro crack formation on the glass capsule by thermal stress effect. To address this non-uniformity problem, a new heater configuration is being proposed. By keeping several points on the heater strip at calculated and constant potential, more uniform heating, hence more reliable wafer bonding could be achieved. The proposed scheme has been successfully demonstrated, and the result shows that it will be very useful in hermetic packaging. Less than 0.2 ㎫ contact Pressure were used for bonding with 150 ㎃ current input for 50${\mu}{\textrm}{m}$ width, 2${\mu}{\textrm}{m}$ height and 8mm $\times$ 8mm, 5mm$\times$5mm, 3mm $\times$ 3mm sized phosphorus-doped poly-silicon micro heater. The temperature can be raised at the bonding region to 80$0^{\circ}C$, and it was enough to achieve a strong and reliable bonding in 3minutes. The IR camera test results show improved uniformity in heat distribution compared with conventional micro heaters. For gross leak check, IPA (Isopropanol Alcohol) was used. Since IPA has better wetability than water, it can easily penetrate small openings, and is more suitable for gross leak check. The pass ratio of bonded dies was 70%, for conventional localized heating, and 85% for newly developed FP scheme. The bonding strength was more than 30㎫ for FP scheme packaging, which shows that FP scheme can be a good candidate for micro scale hermetic packaging.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2008.05a
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• pp.1-46
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• 2008

The ability to control filler performance and fines retention is vital in the development of both filled and non filled grades, respectively. This is very important when achieving the desired sheet structure necessary to maximize machine performance and end user demands. A narrow balance exists in attaining the desired retention and formation particularly in systems with heavier ash loads and producing paper and paper board on higher speed high shear equipment. A new generation of both cationic and anionic micropolymer technologies has been developed. These water based chemistries are volatile organic compound (VOC) and alkyphenol ethoxylate (APE) free. When these novel micropolymers are applied with linear poly-acrylamide or in conjunction with inorganic microparticle technologies (such as silica or swellable minerals), substantial increases in drainage, fibre retention and ash retention are observed. These improvements have been observed not only in high filled wood and non wood containing grades such as fine paper and super calendared sheets (SCA), but also in low filled newsprint grades. Of particular note is the drainage improvement seen with the application of the cationic micropolymers in unbleached packaging grades with poly-acrylamide.

• Phonetics and Speech Sciences
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• v.3 no.3
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• pp.27-33
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• 2011

This paper explores two articulatory characteristics of inter-consonantal coordination observed in lingual-lingual (/kt/, /ks/) and labial-lingual (/pt/) sequences. Using electromagnetic articulometry (EMMA), temporal aspects of the lip movement and lingual movement (of the tongue tip and the tongue dorsum) were examined. Three sequences (/ks/, /kt/, /pt/) were investigated in two respects: gestural overlap in C1C2 and formation duration of coronals in C2 (/t/ or /s/). Results are summarized as follows. First, in a sequence of two stop consonants gestural overlap did not vary with order contrast or a low-level motor constraint on lingual articulators. Gestural overlap between two stop consonants was similar in both /kt/ (lingual-lingual; back-to-front) and /pt/ (labial-lingual; front-to-back). Second, gestural overlap was not simply constrained by place of articulation. Two coronals (/s/ and /t/) shared the same articulator, the tongue tip, but they showed a distinctive gestural overlap pattern with respect to /k/ in C1 (/ks/ (less overlap) < /kt/ (more overlap)). Third, temporal duration of the tongue tip gesture varied as a function of manner of articulation of the target segment in C2 (/ks/ (shorter) < /kt/ (longer)) as well as a function of place of articulation of the segmental context in C1 (/pt/ (shorter) < /kt/ (longer)). There are several implications associated with the results from Korean non-assimilating contexts. First, Korean can be better explained in the way of its language-specific gestural pattern; gestural overlap in Korean is not simply attributed to order contrast (front-to-back vs. back-to-front) or a physiological motor constraint on lingual articulators (lingual-lingual vs. nonlingual-lingual). Taking all factors into consideration, inter-gestural coordination is influenced not only by C1 (place of articulation) but also C2 (manner of articulation). Second, the jaw articulator could have been a factor behind a distinctive gestural overlap pattern in different C1C2 sequences (/ks/ (less overlap) vs. /kt/ and /pt/ (more overlap)). A language-specific gestural pattern occurred with reference to a physiological motor constraint on the jaw articulator.

• Proceedings of the Ginseng society Conference
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• 1984.09a
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• pp.45-48
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• 1984

Ion-pair reverse phase HPLC techniques were used to compare the contents of IAA and IAAsp in the embryogenic and non-embryogenic calli derived from ginseng (Panax ginseng C.A. Meyer) root tissues. The contents of IAA and IAAsp of the embryogenic callus were much higher (7 to 18 X respectively) than those of non-embryogenic callus. There is a distinct fluorescent peak of an unknown component in the HPLC profile of the extract for indolic compounds from non-embryo-genic callus. This distinct difference may be employed as a promising parameter to screen the culture pieces for obtaining the calli with high potential for embryoid formation.