• Journal of Korea Multimedia Society
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• v.21 no.1
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• pp.10-17
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• 2018

Persistence Betty numbers, which are the rank of the persistent homology, are a generalized version of the size theory widely known as a descriptor for shape analysis. They show robustness to both perturbations of the topological space that represents the object, and perturbations of the function that measures the shape properties of the object. In this paper, we present a shape matching algorithm which is based on the use of persistence Betty numbers. Experimental tests are performed with Kimia dataset to show the effectiveness of the proposed method.

• Journal of applied mathematics & informatics
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• v.23 no.1_2
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• pp.57-71
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• 2007

This paper considers how to detect structure change in persistence from I(1) to I(0) with innovations in the domain of attraction of a K-stable law. We derive the asymptotic distribution of test statistic and find that the asymptotic distribution of test statistics depends on the stable index K, which is often typically unknown and difficult to estimate. Therefore the subsampling method is proposed to detect changes without estimating K. We establish the asymptotic validity of this method and assess its performance in finite samples by means of simulation study.

• Tunnel and Underground Space
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• v.8 no.4
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• pp.351-358
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• 1998

A statistical method for assessing the joint persistence based on the in-situ measurement of joint trace length has been derived. This method utilizes the probability density distribution of either the joint trace length or the diameter of hypothetically circular joint diameter depending on the relative size of joint surface to that of the potential keyblock. The stability of potential keyblock with different sizes and joint persistences has been also calculated to illustrate the applicability of the developed method to the design and the safe excavation of large scale underground openings.

• KDI Journal of Economic Policy
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• v.43 no.2
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• pp.23-51
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• 2021

The persistence of the employment shock by COVID-19 has various policy implications during the pandemic and beyond it. After evaluating the impact of the health crisis at the individual level, this study decomposes employment losses into persistent and transitory components using the observed timing of the three major outbreaks and subsequent lulls. The estimation results show that while face-to-face services were undoubtedly hit hard by the COVID-19 crisis, the sectoral shock was less persistent for temporary jobs and self-employment. Permanent jobs in the hard-hit sector showed increasingly large persistent losses through the recurring crises, indicating gradual changes in employer responses. The persistent job losses were concentrated on young and older workers in career transitions, whose losses are likely to have long-term effects. These results suggest that targeted measures to mitigate the persistent effects of the employment shock should take priority during the recovery process.

• Journal of Korea Society of Digital Industry and Information Management
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• v.18 no.3
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• pp.43-53
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• 2022

This study analyzed the learning effect on K-MOOC. It was confirmed how the ease and interaction of K-MOOC affects learning satisfaction and Learning Persistence. The results of the study are as follows. First, it was found that the interaction and ease of K-MOOC learners had a positive effect on learning satisfaction. Second, it was found that the ease and interaction of K-MOOC learners had a positive effect on the Learning Persistence. Third, the satisfaction and willingness of learners with prior course experience of K-MOOC learners were high, and there was a significant difference according to the course experience. This study is meaningful in that the effect of actual learning activities was verified for K-MOOC learners. Based on the results of this study, it is necessary to conduct a comparative study on the K-MOOC activation plan and the case of using K-MOOC at each university.

• Asia Marketing Journal
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• v.17 no.2
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• pp.63-71
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• 2015

In this research, we explore whether mere exposure to external cues with vertical progress (e.g., moving upward or moving downward) can influence individuals' persistence to complete focal tasks. Drawing on the theory of embodied cognition, we propose that, a moving-upward (vs. downward) cue activates the abstract concept of difficulty, which is associated with the physical experience of climbing uphill (vs. downhill). Due to this association between moving uphill and difficulty, merely exposing individuals to the moving-upward cue can induce greater feeling of difficulty and this greater difficulty, in turn, reduce individuals' persistence, compared to exposing individuals to the moving-downward cue. Across three studies, we find supporting evidence for the effect of the external cues with vertical progress on individuals' performance both in physical tasks and in a cognitive task.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.2
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• pp.152-159
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• 1997

The asymptotic convergence of a coupled dynamic system, which is motivated from infinite dimensional adaptive systems, is investigated. The convergence analysis is formulated in abstract Banch spaces and is shown to applicable to a broad class of infinite dimensional systems including adaptive identification and adaptive control. Particularly it is shown that if a uniquely existing solution is p-th power integrable, then the solution converges to zero asymptotically. The persistence of excitation(PE) of a signal which arises in an infinite dimensional adaptive system is investigated. The PE property is not completely known yet for infinite dimensional adaptive systems, however it should be investigated in relation to spatial variable, boundary conditions as well as time variable.

• Journal of Korean Dental Science
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• v.16 no.2
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• pp.164-171
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• 2023

Purpose: To evaluate the antimicrobial persistence of silver diamine fluoride (SDF) and silver fluoride (AgF) on Streptococcus mutans. Materials and Methods: An in vitro experiment was conducted to observe changes in the diameter of the inhibition zone of various materials, including AgF (Riva Star Aqua^TM step 1; SDI), potassium iodine (Riva star aqua^TM step 2; SDI), Fluor protector^® (FP, Ivoclar Vivadent), SDF (Riva star^TM step 1; SDI), Ampicillin (Sigma-Aldrich), Amphotericin B (Nexstar) and negative control on S. mutans. Result: SDF, AgF and FP exhibited significant antimicrobial persistence over the 4 weeks period (P<0.05). At day 28, the diameter of inhibition zone was larger in SDF than in AgF. Conclusion: SDF and AgF have significant antibacterial durability against bacteria commonly associated with dental caries, with the antimicrobial effect lasting for at least 4 weeks. Further clinical studies are needed to validate these findings in vivo.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.18 no.6
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• pp.105-116
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• 2023

While there have been studies on the impact of government financial support on the performance of these enterprises, there is limited research on how entrepreneurs' perceptions of such policies affect business performance. Additionally, there is scarce domestic research on the role of entrepreneurial persistence in achieving and sustaining entrepreneurial goals and its impact on business performance. Therefore, the aim of this study is to analyze how entrepreneurs' perceptions of government policy support affect business performance and to explore the mediating effect of entrepreneurial persistence, shedding light on the significance of perceptions and deepening the understanding of entrepreneurial persistence. This study utilizes entrepreneurs' perceptions of government support for South Korean small and venture enterprises, and entrepreneurship as independent variables, with entrepreneurial persistence as a mediating variable and non-financial performance of businesses as the dependent variable. Data was collected through surveys targeting founders, CEOs, and executives of small and venture enterprises. After excluding incomplete responses, a total of 205 survey responses were used for hypothesis testing. The results of this study are as follows. First, it was verified that the perception of SME policy support and entrepreneurship have a significant positive impact on business performance. Second, it was verified that entrepreneurial persistence partially mediates the relationship between the perception of SME policy support and entrepreneurship and business performance. The theoretical implications of this study are twofold. First, it highlights the significant positive impact of entrepreneurs' perceptions of policy support on the non-financial performance of small and venture enterprises. This contributes to the theoretical understanding by demonstrating that entrepreneurs' perceptions play a role in affecting business performance, in contrast to previous research that focused on the impact of policy financial support on business performance. Second, this study extends the theoretical understanding of entrepreneurial persistence, a relatively understudied concept in domestic research, by demonstrating its mediating role in the relationship between entrepreneurs' perceptions of government support and, entrepreneurship, and business performance. Practically, the study suggests that to enhance the performance of small and venture enterprises, the government should not only expand policy support but also seek ways to increase entrepreneurs' perceptions of such support.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.5
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• pp.758-765
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• 1999

Comparative studies of the effects of rates and frequency of application of dairy slurry on herbage yield and stand persistence of alfalfa and various forage grasses have not previously been conducted. The results being reported here are part of a larger study having a primary objective of comparing the effectiveness of alfalfa (Medicago sativa L.), various grasses and alfalfa-grass mixtures for utilizing nutrients from applied dairy slurry. The objectives of this part of the study were to evaluate the effects of various rates and frequencies of application of slurry on herbage yield and stand persistence of orchardgrass (Dactylis glomerata L.), reed canarygrass (Phalaris arundinacea L.), and alfalfa-orchanrdgreass and alfalfa-reed canarygrass mixtures managed as a 4-cutting management system. A randomized complete block design with treatments in a split plot arrangement with four replicates was used. The main plots consisted of 9 fertility treatments: 7 slurry rate and time of application treatments, one inorganic fertilizer treatment, and an unfertilized control. The sub-plots consisted of the two grasses and two alfalfa-grass mixture mentioned above. Slurry was composed from stored solids scraped from the alleyways of a free-stall housing barn and water added to form a slurry having about 8% solids. Manure was pumped from a liquid spreader tank into 10.4 L garden water cans for manual application to the plots. Herbage yields within species were generally unaffected by various rates of application in the first production year. Herbage yields of grasses and alfalfa-grass mixtures the second year were generally not affected by frequency of application for the same rate of slurry applied. Slurry application resulted in greater herbage yield increases in grasses than alfalfa-grass mixtures in the 4-cutting management system. In general, herbage dry matter yields of grasses from the dairy slurry treatments equaled or exceeded yields from the inorganic fertilizer treatment. Stand ratings of grasses and alfalfa-grass mixtures were not changed by manure application rates. In this study, the highest rate of slurry ($967kg\;total\;N\;ha^{-1}$ in 1995 plus $2,014kg\;N\;ha^{-1}$ in 1996) was not detrimental to herbage yields or stand persistence of any of the species. It was concluded that applying dairy slurry to these cool-season grasses and alfalfa-grass mixtures managed in a 4-cutting system is an acceptable practice from the standpoint of herbage yield and satnd persistence and by doing so the utilization of inorganic fertilizers can be reduced.