• International journal of steel structures
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• v.18 no.5
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• pp.1684-1698
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• 2018

Fragility functions are determined for braced steel moment frames (SMFs) with plans such as square-, T-, L-, U-, trapezoidal-, and semicircular-shaped, subjected to blast. The frames are designed for gravity and seismic loads, but not necessarily for the blast loads. The blast load is computed for a wide range of scenarios involving different parameters, viz. charge weight, standoff distance, and blast location relative to plan of the structure followed by nonlinear dynamic analysis of the frames. The members failing in rotation lead to partial collapse due to plastic mechanism formation. The probabilities of partial collapse of the SMFs, with and without bracing system, due to the blast loading are computed to plot fragility curves. The charge weight and standoff distance are taken as Gaussian random input variables. The extent of propagation of the uncertainties in the input parameters onto the response quantities and fragility of the SMFs is assessed by computing Sobol sensitivity indices. The probabilistic analysis is conducted using Monte Carlo simulations. The frames have least failure probability for blasts occurring in front of their corners or convex face. Further, the unbraced frames are observed to have higher fragility as compared to counterpart braced frames for far-off detonations.

• Computers and Concrete
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• v.30 no.2
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• pp.127-141
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• 2022

In this paper, a numerical procedure is proposed for achieving the minimum cost design of reinforced concrete polygonal column cross-sections under compression and biaxial bending. A methodology is developed to integrate the metaheuristic algorithm Quantum Particle Swarm Optimization (QPSO) with an algorithm for the evaluation of the strength of reinforced concrete cross-sections under combined axial load and biaxial bending, according to the design criteria of Brazilian Standard ABNT NBR 6118:2014. The objective function formulation takes into account the costs of concrete, reinforcement, and formwork. The cross-section dimensions, the number and diameter of rebar and the concrete strength are taken as discrete design variables. This methodology is applied to polygonal cross-sections, such as rectangular sections, rectangular hollow sections, and L-shaped cross-sections. To evaluate the efficiency of the methodology, the optimal solutions obtained were compared to results reported by other authors using conventional methods or alternative optimization techniques. An additional study investigates the effect on final costs for an alternative parametrization of rebar positioning on the cross-section. The proposed optimization method proved to be efficient in the search for optimal solutions, presenting consistent results that confirm the importance of using optimization techniques in the design of reinforced concrete structures.

• The Journal of the Convergence on Culture Technology
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• v.8 no.6
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• pp.625-629
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• 2022

This study was conducted to compare the internal and external fruit quality of highbush blueberry cultivars introduced in Korea. The fruit of blueberry showed a double S-shaped growth curve, and the fruit weight increased significantly per seed increased by 0.02 g. The sugar content ranged from 9.5 to 14.2°Bx, with a large difference between cultivars. And the free sugar was composed of glucose and fructose as a reducing sugar, and mannitol as a sugar alcohol. The organic acid content was 0.7~1.13%, and citric acid was higher than that of malic acid. Fruit hardness showed a berry characteristic that rapidly declined as the coloring progressed.

• Earthquakes and Structures
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• v.24 no.4
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• pp.237-245
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• 2023

Based on novel Galerkin's technique, the theoretical study gives a prediction to estimate the vibrations of FG rotating cylindrical shell. Terms of ring supports have been introduced by a polynomial function. Three different laws of volume fraction are utilized for the vibration of cylindrical shells. Variation frequencies with the locations of ring supports have been analyzed and these ring supports are placed round the circumferential direction. The base of this approach is an approximate estimation of eigenvalues of proper functions which are the results of solutions of vibrating equation. Each longitudinal wave number corresponds to a particular boundary condition. The results are given in tabular and graphical forms. By increasing different value of height-to-radius ratio, the resulting backward and forward frequencies increase and frequencies decrease on increasing length-to-radius ratio. There is a new form of frequencies is obtained for different positions of ring supports, which is bell shaped. Moreover, on increasing the rotating speed, the backward frequencies increase and forward frequencies decreases.

• Korean Journal of Plant Resources
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• v.36 no.3
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• pp.237-255
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• 2023

Variations in phenotypic traits are important for onion genetic improvement. The aim of this study was to identify the phenotypic traits of temporary genetic resources and the best accessions for the development of onion breeding programs. Sixteen phenotypic traits of 79 onion accessions were studied. The descriptive statistics of phenotypic traits exhibited a high variation in onion accessions. Among the 79 evaluated accessions, 64.55% had a large bulb neck width and 44.30% had a circular bulb shape. Principal component analysis showed that six principal components (PCs) accounted for 72.65% of the total variation. The main factors contributing to PC1 were bulb weight, equatorial and bulb polar diameters, plant height, and degree of splitting into bulblets, whereas those contributing to PC2 were the bulb color of the epidermal cells of the fleshy scales and color of the dry skin on the bulb. The accessions were classified into three groups-clusters 1, 2, and 3. Cluster 2 accessions were the most suitable for selecting large and circular bulb-shaped onion cultivars. The phenotypic variation observed in this study may help to select potential accessions for breeding new onion cultivars.

• Transactions of Materials Processing
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• v.32 no.2
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• pp.67-73
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• 2023

To overcome a climate change, manufacturing complex-shaped electric mobility parts becomes one of the important issues for enhancing a performance of motor with reducing their weight. Therefore, development of laser-based additive manufacturing shed on light due to their flexible manufacturing capacity that can be suitable to solve the poor formability of Fe-Si alloys for electric mobility parts. Although there are several studies existed to optimize the performance of additively manufactured Fe-Si alloys, the post-annealing effect was not well investigated yet though this is important to control the texture and mechanical properties of additively manufactured parts. In the present work, annealing effect on the mechanical property and microstructure of additively manufactured Fe-4.5Si alloy was investigated. Because of the ordered phase initiation after annealing, the hardness of additively manufactured Fe-4.5Si alloy increased up to 1173 K while a hardness drop occurs at the 1273 K condition due to the micro-crack initiation. The response surface methodology result represents the 1173 K-5 h sample is an optimal condition to maximize the mechanical property of additively manufactured alloy without micro-cracks.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.224-224
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• 2022

Mungbean(Vigna radiata (L.) R. Wilczek) is one of legume cultivated in south and east Asia. It well cultivated in high temperature and drought condition. In order to establish pure line for genomic studies, the agronomical characteristics of Korean mungbean landraces were evaluated. A total of 324 acessions derived from National Agrobiodiversity Center were selfed two times in 2021 nersery. Tree times of selfed from 324 accessions were characterized. The color of seed coat was divided into three groups: green, yellow and brown. Among them green color was the most common with 91.7%. Flower colors were divided into four groups: yellow, purplish yellow, greenish yellow and purplish green. Among them purplish yellow color had the highest with 77.8%. Out of 324 resources, only 4 showed compound leaves, and all resources had a heart-shaped leaf. The days to first flowering was 31 to 78 days. About 63% of the accessions bloomed 35 to 50 days after sowing. 324 Korean landraces are expected to be used as a population of the Korean mungbean core collection and serve as a basis for genomic breeding materials for mungbean.

• Proceedings of the Korean Society of Crop Science Conference
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• 2023.04a
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• pp.142-142
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• 2023

Cowpea(Vigna unguiculata L. Walp) has excellent physical properties and texture of starch, so it is mainly used in various ways for songpyeon sediment, rice-cake paste, and porridge. To utilize it as various processed products such as songpyeon sediment and cowpea milk, 'Okhyun', which has green cotyledons and black seed coats and can be harvested by combine was developed. A cowpea variety 'Okhyun' was improved from the cross between IT145379 and IT208081 at the JARES in 2022. 'Okhyun' has an erect plant with an intermediate plant habit, a light purple-colored corolla, and heart-shaped leaflets. 'Okhyun' has green cotyledons and black seed coats, and has straight black brown pods when mature. The stem length of 'Okhyun' is 47cm, and the weight of 100-seed weight was 12.9g, which was lower than the control variety 'Okdang'(16.6g). 'Okhyun' contains 25.8mg/100g of anthocyanin, 279mg/100g of total polyphenols, and 335mg/100g of total flavonoids, respectively. The average yield of 'Okhyun' was 1.97ton per hectare, 11% higher than that of the control cultivar 'Okdang'. 'Okhyun'' does not require the installation of an espalier-net net, so it is possible to harvest with a combine. In addition, 'Okhyun' variety with green cotyledons and a black seed coat is expected to contribute to developing regional specialties and various processed products.

• International Journal of Computer Science & Network Security
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• v.23 no.11
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• pp.53-58
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• 2023

The trend of satisfying consumer needs (payment for mobile communication, music services, cab ordering, banking products, and food delivery) on a unified online platform has shaped a digital ecosystem, an instrument creating a unified space of economic interaction. Representatives of e-commerce are major stakeholders in the development of such tools. In particular, subscription services (multiservice subscriptions) allow users to create their own ecosystems based on their personal preferences. The rate of subscription service use is growing around the world, yet understanding of the peculiarities of development of this e-commerce sphere is limited due to insufficient research.The study aims to determine the motives and barriers to the use of subscription services (multiservice subscriptions) by consumers and their relationship with consumer characteristics.Proceeding from an online survey of 200 users, the study determines the relationship between the gender and income of consumers and their use of subscription services, motives and motivators for using subscription services, and barriers to the choice of a particular subscription service. The obtained results may serve as a basis for managerial decisions in e-commerce and for improving the effectiveness of marketing solutions.

• The Research Journal of the Costume Culture
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• v.31 no.5
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• pp.692-704
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• 2023

This study analyzed 214 sports knee braces found on Chinese websites between October 2022 and November 2022 to assess product type (impact protection material, fastening method, and protection method), material composition, size, weight, and main characteristics. The product type was further categorized according to (1) use of hard guard and soft guard protection method; (2) cover type, strap type, and slip-on type fastening method; and (3) pressure type and support type protection method. It also noted the physical shock protection materials used, including foam (EVA or polyurethane) attached to joints as a buffer material and plastic (TPU or PP) that protects the user's knee from external impacts. The study found that the materials that primarily comprise sports knee braces are a combination of nylon, polyester, and neoprene. Additionally, it found that most sports knee braces available on the market are available in three sizes based on knee circumference: M (35-38cm), L (38-41cm), and XL (41-44cm), while some products are available in one size only. Furthermore, the majority of the 214 products studied weighed 200g, followed by 1,000g. Finally, in terms of product characteristics, many sports knee braces utilize ring-shaped silicone pads to distribute the load pressure on the knees or incorporate sturdy adhesive velcro to improve knee stability.