• Clean Technology
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• v.4 no.2
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• pp.11-22
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• 1998

The photo-sensitized oxidation of benzene in water was investigated under various reaction conditions using persulfate, sulfate, nitrate, nitrite and chloride ions as sensitizers. Persulfate ion was proved to be the most effective sensitizer, while sulfate and nitrite could not play any sensitizing role on the benzene photooxidation. When exited together with other ions, the nitrite ion inhibited the photooxidation of benzene by quenching the produced hydroxyl radicals.

• The Journal of Internal Korean Medicine
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• v.19 no.2
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• pp.333-346
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• 1998

In order In study the effects of an immunosuppression and a mitigation of inflammation of Gamiseungmagalgeuntang(GMSG) on the allergic contact dermatitis, contact hypersensitivity assay, mast cell, VCAM-1, and T cell of the lymph node in mice induced allergic contact dermatitis by the contacts-sensitizing DNCB were obsereved after oral administration of GMSG extract. The results of this study were as follows ; 1. Ear swelling in contact hypersensitivity assay was decreased in the GMSG group as compared with DNCB group. 2. It was investigated that mast cells were appeared degranulated type in DNCB group and a number of granulated type was more GMSG group than DNCB group. 3. VCAM-1 expression in epidermis and CD11b positive cell in dermis were decreased In the GMSG group as compared with DNCB group. 4. In the lymph node ,the distribution of CD4, CD8, IL-2R positive cell were decreased at the cortex and medula in the GMSG group as compared with DNCB group.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2000.04a
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• pp.150-151
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• 2000

Some chromophores that can undergo a pronouncend colour change when acted upon an extenal agency, such as light, heat, pH, or chemical agents, have many potential applicationa as functional dyes. They may be used as indicators, optical sensors, biochemical probes, optical and thermal recording materials. The results will investigate donor-acceptor chromophores which have the potential for such colour change processes. In particular, cross-conjugated donor-acceptor chormophores, analogous to indigo and squarylium-type chromophores, will be examined for pH sensitizing and for their oxidation-reduction colour change behaviour.

• Analytical Science and Technology
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• v.12 no.3
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• pp.209-217
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• 1999

To elucidate the decay of the rose bengal (RB) sensitized and thiourea (TU) supersensitized photocurrent, spectroscopic analyses of the dye solution were performed. Absorption and fluorescence spectroscopic analyses of sensitizing solution before and after irradiation enabled to conform the new mechanism of the photocatalytic dimerization between RB and TU. And it was also found that the geometrical arrangement of the transition dipole moment is oblique and the angle between the dipoles is $124^{\circ}$ in the dimer of dye molecules.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.3
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• pp.176-186
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• 1996

As the density of VLSI increases, the conventional logic testing is not sufficient to completely detect the new faults generated in design and fabrication processing. Recently, IDDQ testing becomes very attractive since it can overcome the limitations of logic testing. In this paper, G-ATPG (gyeongsang automatic test pattern genrator) is designed which is able to be adapted to IDDQ testing for combinational CMOS VLSI. In G-ATPG, stuck-at, transistor stuck-on, GOS (gate oxide short)or bridging faults which can occur within priitive gate or XOR is modelled to primitive fault patterns and the concept of a fault-sensitizing gate is used to simulate only gates that need to sensitize the faulty gate because IDDQ test does not require the process of fault propagation. Primitive fault patterns are graded to reduce CPU time for the gates in a circuit whenever a test pattern is generated. the simulation results in bench mark circuits show that CPU time and fault coverage are enhanced more than the conventional ATPG using IDDQ test.

• Journal of Environmental Health Sciences
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• v.26 no.2
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• pp.49-58
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• 2000

The present study was performed to investigate photodegradation rate constants and degradation products of phosphamidon and profenofos by the USEPA method. The two pesticides were very stable in 16 days exposure of sunlight from September 3 to 22, 1999 and humic acid had no sensitizing effect on the photolysis of each pesticide in sunlight. In the UV irradiation test, phosphamidon was rapidly degraded as increasing UV intensity. In case of UV irradiation with TiO2 and with TiO2 powder amount, degradation of profenofos showed no significant difference with UV irradiation. Photodegradation rate of profenofos was slower than that of phosphamidon. In order to identify photolysis products, the extracts of degradation products were analyzed by GC/MS. The mass spectra of photolysis products of phosphamidon were at m/z 153 and 149, those of the profenofos were at m/z 208 and 240, respectively. It was suggested that the photolysis products of phosphamidon were 0, 0-dimethyl phosphate(DMP) and N, N-diethylchloroacetamide, those of profenofos were 4-bromo-2-chlorophenol and 0-ethyl-S-propyl phosphate.

• Journal of Welding and Joining
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• v.16 no.3
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• pp.121-128
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• 1998

The degradation of mechanical properties in the high nitrogen steel HN3 developed for nuclear fusion reactor has been evaluated quantitatively using the small punch(SP) test, X-ray diffraction (XRD) analysis has also been conducted to identify carbides or nitrides precipitated on grain boundaries of the heat treated samples. Mechanical properties of the steel HN3 significantly decreased with increasing heat treatment time and temperature or with decreasing testing temperature. Combination of XRD and metallurgical observation, revealed that the material degradation in the thermally aged steel was caused by precipitation of carbides on the grain boundaries. While the weld metal showed the lowest mechanical properties among various microstructures in GTA weldments. By combining SP test and XRD analysis, cryogenic fracture behaviors and aging degradation for high nitrogen steel could be successfully evaluated in nondestructive manner.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.82.1-82.1
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• 2003

The protective adaptive response to electrophiles and reactive oxygen species is mediated by enhanced expression of phase II detoxifying genes including glutathione S-transferases. ${\alpha}$-Lipoic acid, which exerts prooxidant or antioxidant activities, has been shown to activate the insulin signaling pathway and thus to induce insulin-like actions via PI3-kinase and Akt. Our previous studies have shown that PI3-kinase plays an essential role in Nrf2-or C/EBP${\beta}$-mediated glutathione S-transferase A2 (GSTA2) induction. (omitted)

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.145.2-145.2
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• 2003

We have developed a silver staining method using a dye as a silver sensitizer. Dye staining is performed in combination with silver nitrate staining. Dye-silver staining shortens the time of silver staining (~1 hr) and improves the sensitivity better than that of silver diamine stain (1-10 ng) or comparable to that of silver nitrate stain with glutaraldehyde as a silver sensitizer. In dye staining (silver sensitizing step), it has been proven that the sensitivity is at least 4 times comparing with that of CBBR stain and staining time is about 45 min. (omitted)

• Journal of information and communication convergence engineering
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• v.18 no.4
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• pp.239-244
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• 2020

This study analyzed the influencing factors of learning engagement and teaching presence in online programming practice classes. The subjects of this study were students enrolled in an industrial specialized high school, who practiced creating Arduino circuits and programming using a web-based virtual practice tool called Tinkercad. This research adopted a tool that can measure task value, learning flow, learning engagement, and teaching presence. Based on this analysis, learning flow had a mediating effect between task value and online learning engagement, as well as between task value and teaching presence. Increasing learning engagement in online classes requires sensitizing the learners about task value, using hands-on platforms available online, and expanding interaction with instructors to increase learning flow of students. Furthermore, using virtual hands-on tools in online programming classes is relevant in increasing learning engagement. Future research tasks include: confirming the effectiveness of online learning engagement and teaching presence through pre- and post-tests, and conducting research on various practical subjects.