• Journal of the Korean Society for Library and Information Science
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• v.54 no.4
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• pp.53-82
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• 2020

With the increase in smartphone ownership and Internet usage using smartphones, the information environment is shifting from the existing PC to the smart mobile. The current undergraduate students are called Generation Z who prefer smartphones to PCs and video contents to texts. This study attempted to understand their usage behaviors of electronic resources in an academic library in a smart mobile environment. This study conducted a usage statistics analysis with 61,433 usage records of e-books, audiobooks, and e-learning contents and 1,595 records of users in the A academic library during 3 years from 2016 to 2018. The scope of the data includes the date of use, the subject, the year of publication, the channel of use, and each user's gender, affiliation, status, admission date, and graduation date. This study investigated not only the general characteristics of electronic resource use, but also the usage behaviors according to the user's demographic characteristics. Based on the findings, this study suggested practical service plans that are applicable in the near future and reflect changing circumstances.

• Journal of Korean Society of Forest Science
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• v.97 no.5
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• pp.555-558
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• 2008

Trapping efficiency of various sex pheromone blends of the peach pyralid moth, Dichocrocis punctiferalis was compared by field study to develop monitoring system with its sex pheromone at chestnut orchards in Korea. Five candidates of the sex pheromone blends used for the field trapping of D. punctiferalis males were 70:30, 75:25, 80:20, 85:15 and 90:10 mixture of (E)-10-hexadecenyl aldehyde (E10-16:Al) and (Z)-10-hexadecenyl aldehyde (Z10-16:Al). All lures were treated with 1 or 2 mg of each blends. During 2 years of field survey, the 75:25 blend was usually the most effective in attracting males among 5 blends tested. For the 2nd generation, the best capturing activity for D. punctiferalis male was observed by lure with 75:25 blend. Both 90:10 and 75:25 blends showed highest efficiency for the 3rd generation. In most cases. lures treated with 1 mg of blend caught more male moths than these treated with 2 mg of blend.

• Journal of the Korean Institute of Telematics and Electronics
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• v.19 no.6
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• pp.1-8
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• 1982

In this paper a new analytic method for Ladder networks by weighted tree is proposed. In contrast to conventional tree concept that represents only information structure, in this paper, a tree with hierarchical structure is established by giving wei체t of impedance Z and admittance Y to branch and representing each node of its branch as a pair of voltage and current. Then, by defining generation level from tree structure and by parsing between standand level and arbitrary level, driving point impedance, transfer function and transfer impedance are simultaneously obtained instead of complex calculation method by inspection. The validity of this method is proved by the reciprocal theorem and this method is applied to four-terminal constants and the feedback network.

• The Transactions of the Korea Information Processing Society
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• v.4 no.2
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• pp.596-605
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• 1997

The synamic systrm emplohing the self-squared function, , $f(Z)=z^2+c$, provides the Mandelbrot set which classifies constants c using the divergence of the sequence starting from the origin.To speed-up the generation of Mandelbrot set images, two approaches , called as the divide-and-conquer technique and the triangular boundary tracing technique, have been developed.However , the divede-and-conquer technique genrates sequences of some pixels that so not affect graphical representations of the Mandelbrot set.The triangular boundary tracing tech-mique does noot represent some 8-connected components of the Mandelbrost set.In this paper, we prorose a new ;method which solves the 8-connectivity problem of triangular boundary tracing technique.This algorithm considers the divergence for only pixels which are essential to the graphical repressentation of the Mandelbrot set.It also foves good representations for 8-connected components like hairly structures.

• Journal of Korea Game Society
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• v.21 no.5
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• pp.133-142
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• 2021

This study investigated the effectiveness of 'League of Legends (LoL) game school', an e-sports online training program for relieving youth game over-flow. The Seoul Metropolitan Office of Education's Student Education Institute ran the program. Through this study, it was found that various activities to learn an e-sports game professionally and to explore career paths regarding game had positive effects on students' affections and intrinsic motivation. This study may contribute to helping youth as generation Z understand a healthy game culture.

• Korean Journal of Metals and Materials
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• v.49 no.4
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• pp.275-280
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• 2011

This paper focuses on reliability prediction of long-term creep strength for Modified 9Cr-1Mo steel (Gr. 91) which is considered as one of the structural materials of next generation reactor systems. A "Z-parameter" method was introduced to describe the magnitude of standard deviation of creep rupture data to the master curve which can be plotted by log stress vs. The larson-Miller parameter (LMP). Statistical analysis showed that the scattering of the Z-parameter for the Gr. 91 steel well followed normal distribution. Using this normal distribution of the Z-parameter, the various reliability curves for creep strength design, such as stress-time temperature parameter reliability curves (${\sigma}$-TTP-R curves), stress-rupture time-reliability curves (${\sigma}-t_{r}-R$ curves), and allowable stress-temperature- reliability curves ([${\sigma}$]-T-R curves) were reasonably drawn, and their results are discussed.

• Atmosphere
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• v.34 no.2
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• pp.153-176
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• 2024

At 0843 UTC 30 May 2021, a commercial aircraft encountered severe turbulence at z = 11.5 km associated with the rapid development of Mesoscale Convective System (MCS) in the Gyeonggi Bay of Korea. To investigate the generation mechanisms of Near-Cloud Turbulence (NCT) near the MCS, Weather Research and Forecasting model was used to reproduce key features at multiple-scales with four nested domains (the finest ∆x = 0.2 km) and 112 hybrid vertical layers. Simulated subgrid-scale turbulent kinetic energy (SGS TKE) was located in three different regions of the MCS. First, the simulated NCT with non-zero SGS TKE at z = 11.5 km at 0835 UTC was collocated with the reported NCT. Cloud-induced flow deformation and entrainment process on the downstream of the overshooting top triggered convective instability and subsequent SGS TKE. Second, at z = 16.5 km at 0820 UTC, the localized SGS TKE was found 4 km above the overshooting cloud top. It was attributed to breaking down of vertically propagating convectively-induced gravity wave at background critical level. Lastly, SGS TKE was simulated at z = 11.5 km at 0930 UTC during the dissipating stage of MCS. Upper-level anticyclonic outflow of MCS intensified the environmental westerlies, developing strong vertical wind shear on the northeastern quadrant of the dissipating MCS. Three different generation mechanisms suggest the avoidance guidance for the possible NCT events near the entire period of the MCS in the heavy air traffic area around Incheon International Airport in Korea.

• Fashion & Textile Research Journal
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• v.25 no.3
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• pp.267-279
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• 2023

The current bra market and the purchasing behavior of women of the MZ generation in Korea are reviewed in this study. Therefore, basic data for bra product planning for women of the MZ generation are presented by investigating the wearing status and satisfaction. Through online surveys, 272 questionnaires were obtained and were analyzed through frequency analysis, cross-analysis, t-test, and variance analysis. Generation M and Generation Z share digital culture, but, due to age differences, they are compared by generation. There was, however, little significant difference between these groups. In addition, there was no significant difference between groups when factoring for the time of wearing, place of purchase, and material of bras. However, there were big differences between groups depending on whether bras had wires, lace, and their size, especially in body correction items. According to the results, it is pointless to target each generation when making a bra. Also, the young generation consumers are more interested in functionality than in the design compared to 10 years ago. It will improve consumer satisfaction if two different types of bras are produced; one that corrects the body and one that fits well even if the body is less corrected.

• Journal of Power Electronics
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• v.14 no.5
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• pp.834-841
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• 2014

This paper proposes new active switched-capacitor and switched-inductor Z-source inverter (ASC/SL-ZSI) topologies, which can provide a higher boost ability with a small shoot-through time. The proposed ASC/SL-ZSIs inherit all of the advantages of the classical ZSI, and have a stronger voltage boost inversion ability when compared with the classical ZSI. Thus, the output ac voltage quality is significantly improved. In addition, more cells can be cascaded in the impedance network in order to obtain a very high boost ability. The proposed topologies can be applied to photovoltaic or fuel-cell generation systems with low-voltage renewal sources due to their wide range of obtainable voltages. Both simulations and the experimental results are carried out in order to verify performance of the proposed topologies.

• Proceedings of the KIEE Conference
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• 2006.07c
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• pp.1459-1460
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• 2006

A new gas jet Z-pinch EUV light source having double gas jet electrodes has been developed. It has two nozzles and two diffusers. The EUV beam is collected from the side of pinch plasma, generated in between the inner nozzle and corresponding diffuser. A cylindrical shell of He gas curtain produced by the outer nozzle is specially designed for shielding the debris and suppressing the inner gas expansion. We have succeeded in generating EUV energy of 1.22 mJ/sr/2%BW/pulse at 13.5nm. The estimated dimension of EUV source is to be FWHM diameter of 0.07 mm and length of 0.34 mm, and FW 1/e2 diameter of 0.15 mm and length of 1.2 mm.