• Journal of Photoscience
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• v.7 no.1
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• pp.27-30
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• 2000

The Photoluminescence (PL) measurement results of a very good quality GaN sample grown by metalorganic chemical vapor deposition (MOCVD) are reported. The temperature dependences of peak position, emission intensity, and the full width at half maximum (FWHM) of free-exciton (FX) A and B are presented. Our results show the fast thermal quenching of FX transition intensities and predominantly acoustic phonon scattering of emission line broadening. The transition-energy-shift following the Varshni's empirical equation, and by using it to fit the data, E$\_$A1/(T) = 3.4861 eV -6.046 $\times$ 10$\^$-4/T$^2$ (620.3+ T) eV, E$\_$B1/(T) = 3.4928 eV -4.777 $\times$ 10$\^$-4/T$^2$ / (408.2+ T) eV and E$\_$A2/ = 3.4991 eV -4.426 $\times$ 10$\^$-4/ T$^2$ / (430.6+ T) eV for A(n=1), B(n=1), and A(n=2) are obtained respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.4
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• pp.566-571
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• 2020

To classify a presumed hybrid of imported grouper species acquired from the National Fishery Products Quality Management Service, maternal and paternal lines were identified based on partial sequencing of mitochondrial cytochrome c oxidase 1 (co1) and nuclear recombination activation gene 1 (rag1) genes. The matrilineal species was identified as Epinephleus moara by a partial (760 bp) co1 sequence. Ambiguous sequences with base pairs belonging to E. moara or E. lanceolatus were found in a total of 15 different base pairs in the partial 1,159 bp of the rag1 gene, and the patrilineal species was found to be E. lanceolatus. Therefore, all of the groupers examined in the study were identified to be hybrids of E. moara and E. lanceolatus. In addition, a fast and convenient method using random amplification of polymorphic DNA (RAPD) was established for hybrid discrimination. Hybrids between E. moara ♀ and E. lanceolatus ♂ were identified through specific bands of 387 bp and 433 bp in PRIMER 6.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.1039-1042
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• 2006

Because many corporations computerize process figure enemy who is introducing eCRM fast and are used mainly at past by purpose to detect and analyze and forecast systematic analysis of customer information and various pattern of customer recently, ordinary peoples are trend that is alternated gradually by data mining that can drawand forecast result of good quality easily. Field that this data mining is used representatively is eCRM. In this treatise customer data of A discount store and sale data of 1 years experimenting that forecast customer contribution to base next year through data mining actuality data and data mining through comparison with predicted data are how effective to eCRM prove.

• Macromolecular Research
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• v.17 no.7
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• pp.499-505
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• 2009

General, fast, and efficient stitching methods are presented for the synthesis of Fr$\acute{e}$chet-type dendrimers with linear units at a core, as a preliminary investigation for the synthesis of dendritic-linear-dendritic materials. The synthetic strategy involved an inexpensive, 1,3-dipolar, cycloaddition reaction between an alkyne and an azide in the presence of the Cu(I) species, which is known as the best example of click chemistry. The linear core building blocks, 1,7-octadiyne and 1,6-diazidohexane, were chosen to serve as the alkyne and azide functionalities for dendrimer growth via click reactions with the azide and alkyne-dendrons, respectively. These two building blocks were employed together with the azide- and alkyne-functionalized Fr$\acute{e}$chet-type dendrons in a convergent strategy to synthesize two kinds of Fr$\acute{e}$chet-type dendrimers with different linear core units. This comparative efficiency of the click methodology supports the fast and efficient synthesis of dendritic-linear-dendritic materials with the tailor made core unit.

• Proceedings of the KIEE Conference
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• 1997.07f
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• pp.1989-1992
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• 1997

A new soft switching single stage AC-DC full bridge boost converter with unit input power factor and isolated output is presented. Due to using of the non-dissipative snubber in the primary side, a single stage high-power factor isolated full bridge boost converter has a significant reduction of switching losses in main switching devices and output rectifiers of the primary and secondary side, respectively. The non-dissipative snubber adopted in this study is consisted of a snubber capacitor C. and a snubber inductor $L_r$, a fast recovery snubber diode $D_r$, a commutation diode $D_p$. This paper presents the complete operating principles, theoretical analysis and simulation results.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2003.11a
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• pp.361-365
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• 2003

In this paper, we proposed the effective serial connection methodology of PBG resonator with defect mode. We use the big difference of impedance ratio in connection region, for example dual PBG, for serial connection. This method reduces the PBG cells and is able to control the pole of bandpass filters. This result in flexibility in design of bandpass filter. Our PBG bandpass filter is modeled by using the ideal transmission line model. This model is very easy, fast, and effective for PBG structure.

• Journal of the Korea Safety Management & Science
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• v.12 no.3
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• pp.295-302
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• 2010

Nowadays, due to the development of computers and the information and communication technology, data processing and transmission is made very vastly and fast. The development of the technologies bring many changes and revolutions to the life of ordinary people. Although, e-Business grows continuously, it is in experimental stage in domestic area because of limits of infrastructure. Also, in spite of explosive growth of internet, the research on the internet has not been fully studied yet. The objectives of this study are that how service consumers perceive the flow of e-Business, and that what effect the makes on their satisfaction and re-purchase intention. This means that the research enables a marketing manager to take the meaning of comparative weight among the components of e-Business flow, and to provide very useful information to establish marketing strategies which are close to the consumers.

• Journal of Adhesion and Interface
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• v.7 no.4
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• pp.28-31
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• 2006

Due to the miniaturization of MEMS and microelectronics the joining techniques also have to be adjusted. The dosing technology with viscous adhesives does not permit reproducible adhesive volumes, which are clearly under a nano-liter. A nano-liter means however a diameter of bonding area within the range of several 100 micrometers. Additional, viscous adhesives need a certain time, until they are cross linked or cured. The problem especially in the MEMS is the initial strength, since it gives the time, which is needed for joining an individual adhesive joint. The time up to the initial strength is with viscous, also with fast curing systems, within the range of seconds until minutes. Until the reach of the initial strength, the micro part must be fixed/held. Without sufficient adjustment/clamping it can come to a shift of the micro parts. Also existing micro adhesive bonding processes are not batch able, i.e. the individual adhesive joints of a micro system must be processed successively. In the context of the WCARP III 2006 now an innovative method is to be presented, how it is possible to solve the existing problems with micro bonding. i.e. a method is presented, which is batch able, possess a minimum joining geometry with some micrometers and is so fast that no problems with the initial strength arise. It is a method, which could revolutionize the sticking technology in the micro system engineering.

• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.273-275
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• 2005

Active thermography is being used since several years for remote non-destructive testing. It provides thermal images for remote detection and imaging of damages. Also, it is based on propagation and reflection of thermal waves which are launched from the surface into the inspected component by absorption of modulated radiation. For energy deposition, it use external heat sources (e.g., halogen lamp or convective heating) or internal heat generation (e.g., microwaves, eddy current, or elastic wave). Among the external heat sources, the ultrasound is generally used for energy deposition because of defect selective heating up. The heat source generating a thermal wave is provided by the defect itself due to the attenuation of amplitude modulated ultrasound. A defect causes locally enhanced losses and consequently selective heating up. Therefore amplitude modulation of the injected ultrasonic wave turns a defect into a thermal wave transmitter whose signal is detected at the surface by thermal infrared camera. This way ultrasound thermography(UT) allows for selective defect detection which enhances the probability of defect detection in the presence of complicated intact structures. In this paper the applicability of UT for fast defect detection is described. Examples are presented showing the detection of defects in PCB material. Measurements were performed on various kinds of typical defects in PCB materials (both Cu metal and non-metal epoxy). The obtained thermal image reveals area of defect in row of thick epoxy material and PCB.

• Mass Spectrometry Letters
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• v.2 no.1
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• pp.8-11
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• 2011

Two types of glycerolipids [monoacylglycerols (MAG) and cyclitols] were isolated by reversed phase high-performance liquid chromatography from the methanol extracts of a marine sponge, and analyzed by fast atom bombardment mass spectrometry (FAB-MS) in positive-ion mode. FAB mass spectra of these compounds yielded protonated molecules $[M + H]^+$ and abundant sodiated molecules $[M + Na]^+$ from a mixture of 3-nitrobenzyl alcohol and NaI. The structures of these compounds were elucidated by FAB-collisional-induced dissociation (CID)-tandem mass spectrometry. We carried out collision-indused dissociation (CID) of these lipids in B/E-linked scan mode. The CID B/E-linked scan of $[M + H]^+$ and $[M + Na]^+$ precursor ions resulted in the formation of numerous characteristic product ions through a series of dissociative processes. The product ions formed by charge-remote fragmentation (CRF) provided important information for the identification of the acyl chain structure substituted at the glycerol backbone. Some of the product the ions were diagnostic for the presence of a glycerol backbone or acyl chain structure.