• Journal of the Optical Society of Korea
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• v.19 no.2
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• pp.182-187
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• 2015

This paper presents a new graphical method for selecting a pair of optical glasses to simultaneously achromatize and athermalize an imaging lens made of materials in contact. An athermal glass map that plots thermal glass constant versus inverse Abbe number is derived through analysis of optical glasses and plastic materials in visible light. By introducing the equivalent Abbe number and equivalent thermal glass constant, although it is a multi-lens system, we have a simple way to visually identify possible optical materials. Applying this method to design a phone camera lens equipped with quarter inch image sensor having 8-mega pixels, the thermal defocuses over $-20^{\circ}C$ to $+60^{\circ}C$ are reduced to be much less than the depth of focus of the system.

• The Korean Journal of Mycology
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• v.48 no.2
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• pp.135-149
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• 2020

Da-Lat is a hilly area located in southern Vietnam. Macrofungal diversity of Da-Lat was investigated from 2018 to 2019. A total of 468 macrofungal specimens was collected and identified using the modern species concept and taxonomic and phylogenetic analyses. Among them, internal transcribed spacer(ITS) region of 401 specimens were successfully sequenced and compared with those of related species retrieved from GenBank. In total, 180 specimens were identified at the species level. The sequenced specimens were classified into 2 phyla, 13 orders, 38 families, 93 genera, and 124 species. The remaining 221 specimens (175 species) did not match the species level. This study is the first well-documented taxonomic list of macrofungi collected from southern Vietnam.

• Vacuum Magazine
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• v.2 no.2
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• pp.17-23
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• 2015

Medium Energy Ion Scattering (MEIS) has been successfully used for ultrathin film analysis such as gate oxides and multilayers due to its single atomic depth resolution in compostional and structural depth profiling. Recently, we developed a time-of-flight (TOF) MEIS for the first time, which can analyze a $10{\mu}m$ small spot. Small spot analysis would be useful for test pattern analysis in semiconductor industry and various thin film technology. The ion beam damage problem is minimized due to its improved collection efficiency by orders of magnitude and the ion beam neutralization problem is removed completely for quantitative analysis. Newly developed TOF-MEIS has been applied for gate oxides, ultra shallow junctions, nanoparticles, FINFET structures to provide compositional and structural profiles. Further development for submicron spot analysis and applications for functional nano thin films and nanostructured materials are expected for various nanotechnology and biotehnology.

• Proceedings of the KIEE Conference
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• summer
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• pp.1331-1333
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• 2004

There are many types of BOM, such as EBOM, MBOM, As-Built BOM, As-Designed BOM, Generic BOM, Customized BOM, etc. We should define an adequate BOM to achieve some purposes. In this paper, we proposed BOM structure for EMU Maintenance Information System. First of all, we define Master BOM including all part's information, such as 2D/3D drawings, images, specification, etc. And then we define Object BOM that is functional structure for someone to achieve maintenance works. Object BOM will be applied to configure sales orders, explode aggregate forecasts, and calculate standard cost.

• Industrial Engineering and Management Systems
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• v.12 no.2
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• pp.85-94
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• 2013

This research investigates the supply chain contract between a distributor and a supplier in which the selling period is relatively short in comparison with long production lead time. At the first stage, supplier who is a Stackelberg leader offers the distributor a contract with a set of parameters, and subjected to those parameters, the distributor places the number of initial orders as well as options. In order to purchase the option, the distributor pays non-linear option premium price with respect to the number of purchased options. At the second stage, based on realized demand, the distributor has the right to exercise option as either put or call which is limited up to the number of purchased options. The wholesale price contract is used as a benchmarking contract. This research has confirmed that the supply chain contract with a non-linear option premium price can help to coordinate the supply chain.

• Journal of the Korean Institute of Landscape Architecture International Edition
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• no.2
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• pp.1-8
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• 2004

The purpose of this study is to carry out the quantitative and qualitative analysis of an urban park in the landscape ecological view and to provide the important basic data in the urban development process. The results of this study are as follows. First, in the case of disposition distance analysis in quantitative plans, very necessary regions of the children park are turned out to be 24 sites, of the neighboring park are turned out to be 30 sites, and walking park are turned out to be 22 sites. Second, in the case of undevelopment neighborhood park analysis, priority orders are Daebong Park, Suseong Park Third, in the case of area, shape, and isolation in qualitative plans, interior area of Bummul park is larger than that of Chimsan park and isolation of Bummul park higher than that of Chimmsan.

• Bulletin of the Korean Chemical Society
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• v.9 no.2
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• pp.81-84
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• 1988

The CO oxidation was performed on $H_2$-reduced NiO-${\alpha}-Fe_2O_3$ in the temperature range 150-$250^{\circ}C$. The kinetic study and the conductivity measurements indicate the oxidation reaction follows Langmuir-Rideal type process that is uncommon in heterogeneous catalyst$^1$. No active site is found on the catalyst surface for CO adsorption, but an oxygen vacancy adsorbs an oxygen, and this step is rate initiation. The partial orders are half for $O_2$ and first for CO, respectively. Apparent activation energy for over-all reaction is 9.05 kcal/mol.

• Bulletin of the Korean Chemical Society
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• v.22 no.8
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• pp.833-836
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• 2001

Infrared absorption spectra of $\alpha\omega-diphenylpolyenyl$, anions Ph(CH)nPh- (DPn-, n=7, 9, and 13) in the tetrahydrofuran-d6 solutions was measured in the range of 1700 and 1200 cm-1 . The infrared spectra obtained from anions (DPn) showed considerable difference from their neutral species (DPn); their intensities were enhanced at least two orders of magnitude stronger than their neutral species. The in-plane CH bending modes at 1464 and 1375 cm-1 are correspondingly strengthened with the chain length increased, but the C=C stretching at 1541 cm-1 is weakened and frequencies are not changed. We provide an IR evidence for the first time that the bond order or bond alternations of the anions (soliton) are different from those of radical anions (polaron) as well as neutral species.

• Journal of Labour Economics
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• v.42 no.1
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• pp.107-128
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• 2019

When parental experience improves parenting skills, parents are likely to behave in favor of children of higher birth orders. To examine this hypothesis, this study analyzes birth month based on birth order of children in South Korea where parents prefer to have babies in the earlier months of a year. This study finds that while more babies are born in the earlier months, second-born children are more likely to be so than first children. This implies that parental experience makes for better parents.

• Journal of Magnetics
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• v.7 no.4
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• pp.156-159
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• 2002

We have investigated the escape rate of nano-magnetic particle with a magnetic field applied along the easy axis. The model studied here is described by the Hamiltonian H=$K_1\hat{S}{_z^2}$ ＋ $K_2\hat{S}{_y^2}$ ＋ $g{\mu}_bB$ $\hat{S}_x(K_1>K_2>0)$ and the escape rate was calculated with in the semiclassical approximation. We have obtained a diagram for orders of the phase transition depending on the anisotropy constant and the external field. For $K_2$/$K_1>$0.85 the present model reveals the existence of the first order transition within the quantum regime.