• Structural Engineering and Mechanics
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• v.6 no.3
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• pp.327-337
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• 1998

In this paper, the first-order ordinary differential constitutive equations of endochronic theory are incorporated into finite element formalism. A theoretical investigation is performed on the ratchetting effect of a stepped beam subjected to steady tension and cyclic bending. Experimental data of lead alloy found in literature are used for comparison. Those data reveal that the endochronic prediction yields more adequate results than those predictions using the plasticity models with isotropic hardening or kinematic hardening, as employed by Hardy, et al. (1985).

• International Journal of Industrial Entomology and Biomaterials
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• v.35 no.2
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• pp.97-99
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• 2017

Eleven polymorphic microsatellite loci were developed and characterized for Dorcus hopei in this study. The number of alleles varied from 2 to 21. The observed heterozygosity and expected heterozygosity ranged from 0.1058 to 0.9744 and 0.0997 to 0.8941, respectively. Two loci showed low polymorphism, while the rest were highly polymorphic. Six loci deviated from Hardy-Weinberg Equilibrium. The set of markers will provide effective tools for examining the population genetic structures and be helpful for managing wild population in D. hopei.

• Journal of Apiculture
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• v.32 no.4
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• pp.327-332
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• 2017

In this study, we studied the changes in antioxidant activity of Actinidia arguta fruit of Autumn Sense cultivar during fruit ripening. The aim of this investigation was to find the knowledge of the changes of physiochemicals associated with fruit quality, antioxidant properties (free-radical scavenging activity and reducing power), total phenolics and vitamin C during fruit ripening. The highest free-radical scavenging activity (at $100{\mu}g/ml$) and reducing power (at $100{\mu}g/ml$) in A. arguta fruit were 78.57% and 0.22, respectively. Total phenolic content and vitamin C content in fruit of 10 days after fruit set were $639.48{\mu}g/g$ and $1052.2{\mu}g/g$, respectively. In general, the antioxidant activity and the related parameters, including total phenolic content and vitamin C content decreased during fruit ripening. These results improve knowledge of the effect of ripening on the antioxidant activity and related compounds contents that could help to establish the optimum A. arguta fruit harvest data for various usages.

• Korean Journal of Mathematics
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• v.29 no.1
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• pp.75-80
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• 2021

For a locus with two alleles (IA and IB), the frequencies of the alleles are represented by $$p=f(I^A)={\frac{2N_{AA}+N_{AB}}{2N} },\;q=f(I^B)={\frac{2N_{BB}+N_{AB}}{2N}}$$ where NAA, NAB and NBB are the numbers of IA IA, IA IB and IB IB respectively and N is the total number of populations. The frequencies of the genotypes expected are calculated by using p2, 2pq and q2. So in this paper, we consider the method of whether some genotypes is in Hardy-Weinburg equilibrium. Also we calculate the probability generating function for the offspring number of genotype produced by a mating of the ith male and jth female under a diploid model of N population with N1 males and N2 females. Finally, we have conditional joint probability generating function of genotype frequencies.

• Communications of the Korean Mathematical Society
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• v.37 no.1
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• pp.163-176
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• 2022

In this paper, we introduce some new classes of generalized mappings and prove some common fixed point theorems for a pair of asymptotically regular mappings. Our results extend and improve various well-known results due to Kannan, Reich, Wong, Hardy and Rogers, Ćirić, Jungck, Górnicki and many others. In addition to it, a sequential fixed point for a mapping which is the point-wise limit of a sequence of functions satisfying Ćirić-Proinov-Górnicki type mapping has been proved. Supporting examples have been given in strengthening hypotheses of our established theorems.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.27 no.3
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• pp.160-179
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• 2023

In this paper, we investigate the existence and diameter of the approximate fixed point results on E-metric spaces (not necessarily complete) by using various cyclic contraction mappings, including the B-cyclic contraction, the Bianchini cyclic contraction, the Hardy-Rogers cyclic contraction, and so on. Additionally, we prove the approximate fixed point results for rational type cyclic contraction mappings, which were discussed mainly in [35] and [37], in the setting of E-metric space. Also, a few examples are provided to demonstrate our findings. Subsequently, we discuss some applications of approximate fixed point results in the field of applied mathematics rigorously.

• Communications of the Korean Mathematical Society
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• v.38 no.2
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• pp.401-430
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• 2023

In this paper, we prove L^p estimates of a class of singular integral operators on product domains along surfaces defined by mappings that are more general than polynomials and convex functions. We assume that the kernels are in L(log L)² (𝕊^n-1 × 𝕊^m-1). Furthermore, we prove L^p estimates of the related class of Marcinkiewicz integral operators. Our results extend as well as improve previously known results.

• The Korean Journal of Mycology
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• v.50 no.4
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• pp.361-365
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• 2022

Here, Podospora leporina was isolated and cultured from Cypripedium guttatum Sw. (spotted lady's slipper), which was designated as an endangered wildlife class 1 by the Ministry of Environment. Further, Podospora sp., which is found in Calanthe discolor Lindl. (Japanese hardy orchid) root is recorded as an endophytic fungus in Jeju Island, Korea. However, there is no existing record of Podospora spp. Thus, in this study, we analyzed the morphological characteristics and two molecular markers, internal transcribed spacer (ITS) and large ribosomal subunit (LSU), of P. leporina and compared these data with other relative species. Consequently, this endophytic fungal species was confirmed as an unrecorded species in Korea, so we presented cultural characteristics and microstructures, such as the conidia of P. leporina.

• Korean Journal of Mathematics
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• v.32 no.2
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• pp.329-348
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• 2024

In this text, we investigate some fixed point results in double-controlled cone metric spaces using several contraction mappings such as the B-contraction, the Hardy-Rogers contraction, and so on. Additionally, we prove the same fixed point results by using rational type contraction mappings, which were discussed by the authors Dass. B. K and Gupta. S. Also, a few examples are included to illustrate the results. Finally, we discuss some applications that support our main results in the field of applied mathematics.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.7 no.1
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• pp.123-127
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• 1969

The studies were conducted to know the relationship between $\beta$-amlyase activities and hardiness for the germinated seedlings of, winter wheat varieties which were classified with eye estimated cold resistance in field as, susceptible, moderate and resistant. These varieties were tested in continued five days from germination in four replicated split plot design. For the measurement of $\beta$-amylase, improved A. K. Balls method (2) was employed. Result obtained will be summarized as follows. 1. Tested varieties showed highly significant differences in $\beta$-amylase activity, while no differences were obtained between dates after germination. 2. Winter hardy varieties, Yukseung ＃3, Chin Kwang and Suwon＃85 showed higher amylase activities than the moderate hardy varieties, Jukdalma, Kangdosinryuk and Norin ＃4, while lower activities were measured in susceptible varieties, Norin ＃6, Kangdo and Norin＃12. 3. With measurement of $\beta$-amylase activity, rurther detail classification to cold resistance is seemed available than eye-estimating in the field condition. 4. In accordance with testing dates, amylase activities were not so clear on 1st, 2nd, 4th and 5th days from germination, while clear differences were found on 3rd day from germination. 5. Amylase activity obtained on 3rd day after germination is considered easy and effective method to estimate cold resistance of wheat varieties with a classification standard.