• Journal of Advanced Information Technology and Convergence
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• v.8 no.2
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• pp.59-67
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• 2018

The minimum power supply voltage of a typical bandgap current reference (BGCR) is limited by operating temperature and input common mode range (ICMR) of a feedback amplifier. A new BGCR using a bandgap voltage generator (BGVG) is proposed to minimize the effect of temperature, supply voltage, and process variation. The BGVG is designed with proportional to absolute temperature (PTAT) characteristic, and a feedback amplifier is designed with weak-inversion transistors for low voltage operation. It is verified with a $0.18-{\mu}m$ CMOS process with five corners for MOS transistors and three corners for BJTs. The proposed circuit is superior to other reported current references under temperature variation from $-40^{\circ}C$ to $120^{\circ}C$ and power supply variation from 1.2 V to 1.8 V. The total power consumption is $126{\mu}W$ under the conditions that the power supply voltage is 1.2 V, the output current is $10{\mu}A$, and the operating temperature is $20^{\circ}C$.

• International journal of advanced smart convergence
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• v.11 no.2
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• pp.102-107
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• 2022

Smart home systems for safety and security are in high demand and always needed for many reasons including people's desire to feel safe in their own houses and to avoid a high rate of crime. In the current research, we investigate the role of individuals' motivational orientation to prevention in their responses to smart home systems for safety and security. That is, this research examines whether individuals' attitudes toward smart home systems for safety and security vary depending on their level of prevention orientation. Specifically, it is hypothesized that individuals with strong (vs. weak) prevention orientation will have more positive attitudes toward smart home systems for safety and security. In support of the hypothesis, the results indicate that respondents in the strong (vs. weak) prevention orientation reported significantly more positive attitudes toward smart home systems for safety and security. Our findings imply that individuals' motivational orientation to prevention may be an effective marketing and segmentation tool in facilitating their favorable responses to the smart home systems for safety and security.

• International journal of advanced smart convergence
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• v.12 no.2
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• pp.108-116
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• 2023

Smart home and artificial intelligence technologies are developing rapidly, and various smart home systems associated with artificial intelligence (AI) improved the quality of living for people. In the present research, we examine the role of individuals' motivational system in their responses to the application of AI in smart homes. In particular, this research focuses on individuals' prevention motivational system and investigates whether individuals' attitudes toward the application of AI in smart homes differ according to their level of prevention motivation. Specifically, it is hypothesized that individuals with strong (vs. weak) prevention motivation will have more favorable attitudes toward the application of AI in smart homes. Consistent with the hypothesis, the results reveal that the respondents in the strong (vs. weak) prevention motivation reported significantly more favorable attitudes toward the six types of AI-based application in smart homes (e.g., AIbased AR/VR games, AI pet care system, AI robots, etc.). Our findings suggest that individuals' prevention motivational system may be an effective market segmentation tool in facilitating their positive responses to the application of AI in smart homes.

• Tunnel and Underground Space
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• v.23 no.2
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• pp.110-119
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• 2013

It is generalized to measure the arch settlement and convergence during tunnel construction for monitoring its mechanical stability. The initial convergence rate a day is defined from the first convergence measurement and the final convergence defined as the convergence measured lastly. The initial and the final tunnel arch settlement are defined like the preceding convergence. In the study, the relations between the initial and final displacements of a shallow tunnel are analyzed. The measurements were performed in the tunnel of subway 906 construction site in Seoul. The overburden is 10-20 m and the tunnel goes through weathered soil/rock. The width and height of the tunnel are about 11.5 m, 10m, respectively. So this is a shallow tunnel in weak rock. The length of tunnel is about 1,820 m and the tunnel was constructed in 2 stages, dividing upper and lower half. The numbers of measurement locations of arch settlement and convergence are 184 and 258, respectively. As a result, the initial displacement rate and the final displacement are comparatively larger in the section of weathered soil.

• Journal of Digital Convergence
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• v.20 no.2
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• pp.141-154
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• 2022

This study aims to investigate how tie strength in business networks affects successful knowledge sharing, as well as the impact of environmental uncertainty on the relationship between knowledge sharing and tie strength. We gathered data through a questionnaire-based survey of 310 employees affiliated with a high-technology industry in Korea. The results highlighted the positive influence of strong ties on tacit knowledge sharing and weak ties on explicit knowledge sharing. Additionally, in this study, we determine that strong ties are strengthened to share tacit knowledge with exchange parties when environmental uncertainty is high, whereas weak ties may remain unaffected by environmental uncertainty. This study contributes to the literature on tie strength and knowledge sharing by applying social capital theory to a high-technology industry. The findings suggest that firms must take advantage of strong and weak ties to facilitate knowledge sharing to enhance competency, create novel knowledge, and obtain a competitive advantage.

• The Journal of the Korea Contents Association
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• v.6 no.4
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• pp.63-68
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• 2006

For the almost co티am convergent series $S_n$ of independent random variables, by investigating the limiting behavior of the tail series, $T_n=S-S_{n-1}=\sum_{i=n}^{\infty}X_i$, the rate of convergence of the series $S_n$ to a random variable S is studied in this paper. More specifically, the equivalence between the tail series weak law of large numbers and a limit law is established for a quasi-monotone decreasing sequence, thereby extending a result of Previous work to the wider class of the norming constants.

• International Journal of Industrial Entomology and Biomaterials
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• v.48 no.1
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• pp.25-32
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• 2024

Soy protein isolate (SPI) has garnered researchers' attention due to its abundance, costeffectiveness, excellent biocompatibility, hemo-compatibility, and biodegradability. However, SPI faces limitations in application due to poor processability and weak mechanical strength. Substantial efforts have been made to address these challenges. In this preliminary study, glycerol and biofibers were added to SPI to improve the mechanical properties and film forming, and glyoxal was employed to crosslink SPI molecules. The microstructure and mechanical properties of the resulting SPI/composite films were evaluated. A 15% addition of glycerol proved sufficient for good film formation. Among the biofibers, short SF microfibers were the most effective in enhancing breaking strength, while TEMPO-oxidized CNF (cellulose nanofiber) excelled among CNFs. Crosslinking with glyoxal significantly enhanced the mechanical properties, with the type of biofiber minimally affecting the mechanical properties of the crosslinked SPI composite films.

• Journal of the Korean Mathematical Society
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• v.52 no.3
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• pp.503-522
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• 2015

In this paper, we consider the problem of testing for a parameter change in nonlinear time series models with GARCH type errors. We introduce two types of cumulative sum (CUSUM) tests: estimates-based and residual-based tests. It is shown that under regularity conditions, their limiting null distributions are the sup of independent Brownian bridges. A simulation study is conducted for illustration.

• Journal of the Chungcheong Mathematical Society
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• v.25 no.3
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• pp.531-541
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• 2012

Feynman's operational calculus for noncommuting operators was studied by means of measures on the time inteval. And various stability theorems for Feynman's operational calculus were investigated. In this paper we see the time-dependent stability properties when the operator-valued functions take their values in a separable Hilbert space.

• Communications of the Korean Mathematical Society
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• v.13 no.3
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• pp.501-513
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• 1998

In this paper, we deal with the asymptotic behavior for the almost-orbits {u(t)} of an asymptotically nonexpansive semigroup S = {S(t) : t $\in$ G} for a right reversible semitopological semigroup G, defined on a suitable subset C of Banach spaces with the Opial's condition, locally uniform Opial condition, or uniform Opial condition.