• Macromolecular Research
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• v.10 no.6
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• pp.297-303
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• 2002

We have investigated the microstructural properties of a weakly charged polyelectrolyte modeled with both Hookean spring and Debye-Huckel potential, by employing a novel hybrid scheme of molecular dynamics (MD) and Monte Carlo (MC) simulations. Although the off-lattice pivot step facilitates the earlier computations stage, it gives rise to oscillations and hinders the stable equilibrium state. In order to overcome this problem, we adopt the MC off-lattice pivot step in early stage only, and then switch the computation to a pure MD step. The result shows that the computational speed-up compared to the previous method is entirely above 10 to 50, without loss of the accuracy. We examined the conformations of polyelectrolyte in solvents in terms of the end-to-end distance, radius of gyration, and structure factor with variations of the screening effects of solvent and the monomer charges. The emphasis can favorably be given on the elongation behavior of a polyelectrolyte chain, with observing the simultaneous snapshots.

• Journal of information and communication convergence engineering
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• v.20 no.1
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• pp.31-40
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• 2022

Coronary heart disease (CHD) is a comorbidity of COVID-19; therefore, routine early diagnosis is crucial. A large number of examination attributes in the context of diagnosing CHD is a distinct obstacle during the pandemic when the number of health service users is significant. The development of a precise machine learning model for diagnosis with a minimum number of examination attributes can allow examinations and healthcare actions to be undertaken quickly. This study proposes a CHD diagnosis model based on feature selection, data balancing, and ensemble-based classification methods. In the feature selection stage, a hybrid SVM-GA combined with fast correlation-based filter (FCBF) is used. The proposed system achieved an accuracy of 94.60% and area under the curve (AUC) of 97.5% when tested on the z-Alizadeh Sani dataset and used only 8 of 54 inspection attributes. In terms of performance, the proposed model can be placed in the very good category.

• Electronics and Telecommunications Trends
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• v.38 no.3
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• pp.11-19
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• 2023

Drones, which were early operated by remote control, have evolved to enable autonomous flight by combining various sensors and software tools. In particular, autonomous flight of drones was possible since the application of GNSS-RTK (global navigation satellite system with real-time kinematic positioning), a precision satellite navigation technology. For instance, unmanned drone delivery based on GNSS-RTK data was demonstrated for pizza delivery in Korea for the first time in 2021. However, the vulnerabilities of GNSS-RTK should be overcome for delivery drones to be commercialized. In particular, jamming in the navigation system and low positioning accuracy in urban areas should be addressed. Solving these two problems can lead to stable flight, takeoff, and landing of drones in urban areas, and the corresponding solutions are expected to establish a hybrid positioning technology. We discuss current trends in hybrid positioning technology that can either replace or complement GNSS-RTK for stable drone autonomous flight.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.17 no.5
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• pp.151-168
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• 2022

Nowadays companies are required to achieve social goals beyond maximizing shareholder profits. Accordingly, it is important to pursue both the economic and social goals of a company at the same time. Thus the importance of hybrid organizations is increasing theoretically and practically. In particular, since hybrid organizations essentially have the complexity of pursuing both economic and social purposes, the institutional demands of various stakeholders surrounding hybrid organizations are also conflicting. Several previous studies have considered how hybrid organizations respond to these conflicting institutional demands, but most studies are limited to studying at a specific point in time. As a result, there was a limit to analyzing the dynamics in response to conflicting institutional demands as the hybrid organization expanded its business. This study predicted that the hybrid organization would take selective coupling with conflicting institutional demands and that the process of responding to institutional demands would change according to the organization's growth. In this study, we had a case study about Noul and Enuma, social ventures that operate relatively advanced business models with outstanding results in innovation and technology. As a result, social ventures show a selective coupling for conflicting institutional demands, and the selective coupling process changes as their business model are advanced. Specifically, in the early stages of the business, it appears to respond to economic and social demands at the same time with a single business model. When the business is advanced, two or more business models are operated, some of which respond to economic needs and some of which respond to social needs. In the early stages of business, social ventures respond to economic and social demands with a single business model to gain legitimacy and survive in the institutional demands. But when they enter the business growth period, they try to separate business models which respond to economic and social values because they pursue sustainable growth and challenge large-scale missions. Overall, this study attempted to contribute to an in-depth understanding of hybrid organizations by identifying that the method of responding to conflicting institutional demands varies depending on the growth process of social ventures.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.5
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• pp.613-619
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• 2005

Indigenous Yakutian cattle' adaptation to the hardest subarctic conditions makes them a valuable genetic resource for cattle breeding in the Siberian area. Since early last century, crossbreeding between native Yakutian cattle and imported Simmental and Kholmogory breeds has been widely adopted. In this study, variations at 22 polymorphic microsatellite loci in 5 populations of Yakutian, Kholmogory, Simmental, Yakutian-Kholmogory and Yakutian-Simmental cattle were analysed to estimate the genetic contribution of Yakutian cattle to the two hybrid populations. Three statistical approaches were used: the weighted least-squares (WLS) method which considers all allele frequencies; a recently developed implementation of a Markov chain Monte Carlo (MCMC) method called likelihood-based estimation of admixture (LEA); and a model-based Bayesian admixture analysis method (STRUCTURE). At population-level admixture analyses, the estimate based on the LEA was consistent with that obtained by the WLS method. Both methods showed that the genetic contribution of the indigenous Yakutian cattle in Yakutian-Kholmogory was small (9.6% by the LEA and 14.2% by the WLS method). In the Yakutian-Simmental population, the genetic contribution of the indigenous Yakutian cattle was considerably higher (62.8% by the LEA and 56.9% by the WLS method). Individual-level admixture analyses using STRUCTURE proved to be more informative than the multidimensional scaling analysis (MDSA) based on individual-based genetic distances. Of the 9 Yakutian-Simmental animals studied, 8 showed admixed origin, whereas of the 14 studied Yakutian-Kholmogory animals only 2 showed Yakutian ancestry (>5%). The mean posterior distributions of individual admixture coefficient (q) varied greatly among the samples in both hybrid populations. This study revealed a minor existing contribution of the Yakutian cattle in the Yakutian-Kholmogory hybrid population, but in the Yakutian-Simmental hybrid population, a major genetic contribution of the Yakutian cattle was seen. The results reflect the different crossbreeding patterns used in the development of the two hybrid populations. Additionally, molecular evidence for differences among individual admixture proportions was seen in both hybrid populations, resulting from the stochastic process in crossing over generations.

• Journal of the Korean Society of Tobacco Science
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• v.6 no.2
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• pp.179-184
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• 1984

This experiment was carried out to select the suitable burley varieties for paddy field. Two varieties, two $F_1$ hybrids and three $F_1$ hybrids with pale yellow line which were all early maturing were tested in the paddy field condition. The results were as follows. 1. Va 528 and all $F_1$ hybrids flowered 4-8 days earlier than Burley 21. 2. Leaf maturity among varieties and $F_1$ hybrids were not significantly different at first priming, but significant differences were detected from second to forth primings. (MS Ky 12x JB 7802-30)Fl and (MS Br 21 x L8)$F_1$ hybrids matured 3-5 days earlier than Burley 21. Pale yellow hyorids matured early, yielded high and were favorable in physical properties, but were low in quality. 4. Va 528 and (MS Br 21 x L8) $F_1$ hybrid showed earthy maturing, high yield and good quality compared with Burley 21. So two varieties were considered suitable for paddy field cultivation.

• Journal of Aquaculture
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• v.10 no.2
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• pp.179-187
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• 1997

Early development growth and sexual phenomena of the hybrid between male spotted flounder (Verasper variegatus) and female olive flounder (Paralichthys olivaceus) were investigated. The hybrid produced was newly called the "Bumnupchi" in Korean name, "Mottled flounder" in English name. Fertilization rate, hatching rate and early survival rate of the mottled flounder were 56.9~72.3%, 86.7~92.5% and 89.1~96.0%, respectively. At 50th day and 240th day after hatching, they were 2.1$\pm0.2cm\;and\;22.9\pm2.1cm\;in\;total\;length, \;0.10\pm0.002g\;and\;179.0\pm38.5g$ in body weight, respectively. Eye position of the mottled flounder was mixed with both dextral (77.7%) and sinistral type (22.3%). Gonads were differentiated into ovarian type and testis type at 80th day after hatching, and its ratio was 1:1 (P>0.05). Most Gonads seemed to be sterile without having germ cell, whereas only 3.6% of investigated indiciduals turned out to have oocytes in the gonad. When the induction of sex reversal were attempted by daily oral administration of $17\beta$-methyltestosterone (0.5mg/kg fish) andestradiol-17$17\beta$(0.5mg/kg fish)from 40th to 100th day after hatching, both testis and ovary type were induced 81.9% and 87.7% of each hormone-treated fish, respectively.fish, respectively.

• Korean Journal of Breeding Science
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• v.43 no.3
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• pp.172-176
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• 2011

'Suan' is a new $F_1$ hybrid variety of rapeseed (Brassica napus L.) with early maturing and high oleic acid. This hybrid variety was bred by the cross between Mokpo-CGMS (male sterile line) and 8516-B-5-6-5-3 (restore line) for the production of bio-diesel and edible oil in 2006. 'Suan' has green and parted leaf, yellowish flower, and black seed coat. 'Suan' is more tolerant to lodging and stem rot compared to 'Sunmang', check variety. The ripening date of 'Suan' is June 2nd which is 6 days earlier than 'Sunmang'. Yield trials were conducted from 2006 to 2007 and regional adaptation trials were examined at five locations each in 2008 and 2009. The average seed yield of regional adaptation trials was 381 kg/10a that was 4% higher than that of 'Sunmang'. Total oil content of 'Suan' was 44.3%. Oleic acid content was 68.3%, which is 5.2% higher than 'Sunmang' but, erucic acid was not detected. Total glucosinolate content was 2.31 mg/g. Therefore, this variety is recommended as a leading variety at southwestern area including Jeonnam, Jeonbuk and Kyongnam provinces of South Korea.

• FLOWER RESEARCH JOURNAL
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• v.16 no.1
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• pp.12-16
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• 2008

This study was carried out to produce haploid plants to verify a systematic breeding program and genetic analysis. Effect of developmental stage of pollen grains and pre-treatment temperature on production of haploid plants was investigated. Microscopic investigation of the explants (Lilium Asiatic hybrid 'reamland' revealed that the length of flower bud at 23.0-24.9, 25.0-26.9, and 27.0-28.9 mm long coincided with tetrad, uninucleate, and binucleate, respectively. When the efficiency of the anther culture from microgametogenetic stages was tested, late uninucleate to early binucleate stage, having the length of 23.0 to 28.0 mm long flower bud, was the best. The frequencies of the callus induction and plant regeneration from the stage mentioned above were 17.8 and 6.7%, respectively. When calli were cultured on the MS medium containing picloram and zeatin at $25^{\circ}C$, shoots were obtained. Roots of regenerated plantlets were confirmed as haploid through an microscopic observation.

• Korean Journal of Breeding Science
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• v.42 no.3
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• pp.236-240
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• 2010

'Jomang' is a new $F_1$ hybrid variety of rapeseed (Brassica napus L.) with early maturation, high yield and high oleic acid. This hybrid variety was developed from the cross between Mokpo-CGMS (male sterile line) and 8516-B-5-6-5-3 (restore line) for the production of edible oil and biodiesel in 2006. Yield trials were conducted from 2007 to 2008, and regional adaptation trials were examined at four locations in 2008. 'Jomang' has green and parted leaf, yellowish flower and black seed coat. The ripening date of 'Jomang' is 1~4 days earlier than 'Sunmang' and 'Tammiyuchae'. The average seed yield of the regional adaptation trials was 406 kg/10a, which was 7% and 42% higher than those of 'Sunmang' and 'Tammiyuchae,' respectively. Total oil content of 'Jomang' was 44.5%. 'Jomang' has no erucic acid in fatty acid composition. However, oleic acid content is 68.2%, which is 3.4% and 5.1% higher than 'Tammiyuchae' and 'Sunmang,' respectively. Total glucosinolate content was 2.31 mg/g. Therefore, this variety is recommended as a leading variety at southwestern area including Jeonnam, Jeonbuk and Kyongnam provinces and Cheju island of Korea.