• Computers and Concrete
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• v.32 no.5
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• pp.527-541
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• 2023

This paper emphasizes the use of CFT columns in frame structures subjected to strong horizontal forces and shows that the efficiency of using CFT columns is increased when the plastic design approach is adopted. Because the plastic design approach is based on redistribution of the force of the internal member, a double node for the rotational degrees of freedom, where the adjacent two rotational degrees of freedom can be connected by a non-dimensional spring element, is designed and implemented into the formulation. In addition, an accompanying criterion is considered in order to make it possible to describe the continuous moment redistribution in members connected to a nodal point up to a complete plastic state. The efficiency of CFT columns is reviewed in comparison with RC columns in terms of the cost and the resistance capacity, as defined by a P-M interaction diagram. Three representative frame structures are considered and the obtained results show that the most efficient and economical design can be expected when the use of CFT columns is considered on the basis of the plastic design, especially when a frame structure is subjected to significant horizontal forces, as in a high-rise building.

• Korean Journal of Agricultural Science
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• v.50 no.4
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• pp.799-808
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• 2023

Globally, abnormal climate phenomena have led to an increase in rainfall intensity, consequently causing a rise in flooding-related damages. Agricultural areas, in particular, experience significant annual losses every year due to a lack of research on flooding in these regions. This study presents a comprehensive analysis of the flood event that occurred on July 16, 2017, in the agricultural area situated in Sindaedong, Heungdeok-gu, Cheongju-si. To achieve this, the EPA (United States Environmental Protection Agency) Storm Water Management Model (SWMM) was employed to generate runoff data by rainfall information. The produced runoff data facilitated the identification of flood occurrence points, and the analysis results exhibited a strong correlation with inundation trace maps provided by the Ministry of the Interior and Safety (MOIS). The detailed output of the SWMM model enabled the extraction of time-specific runoff information at each inundation point, allowing for a detailed understanding of the inundation status in the agricultural area over different time frames. This research underscores the significance of utilizing the SWMM model to simulate inundation in agricultural areas, thereby validating the efficacy of flood alerts and risk management plans. In particular, the integration of rainfall data and the SWMM model in flood prediction methodologies is expected to enhance the formulation of preventative measures and response strategies against flood damages in agricultural areas.

• The Korean Journal of Pesticide Science
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• v.14 no.3
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• pp.226-234
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• 2010

Foliage residue toxicity experiment was performed against honeybee (Apis mellifera) with bifenthrin, a synthetic pyrethroid insecticide with strong acute contact toxicity and imidacloprid, a neo-nicotinoid insecticide with strong acute oral toxicity to know the honeybee toxicity at the residue level on the leaves of alfalfa and apple. Also, the formulation differences to honeybee toxicity were investigated with WP (2%) and EC (1%) of bifenthrin and WP (10%) and SL (4%) of imidacloprid. Generally, foliage residual toxicity of honeybee and residual amounts of tested insecticides was higher in alfalfa leaves with large leaf area per unit weight than in apple leaves. While on the other hand, the only bifenthrin WP treatment showed higher honeybee toxicity on apple leaves than alfalfa. Although imidacloprid showed higher residue amounts ranged $4.9{\sim}25.4\;mg{\cdot}kg^{-1}$ than bifenthrin ranged $0.6{\sim}12.7\;mg{\cdot}kg^{-1}$ on the leaves, the residual toxicity to honeybee was lower than bifenthrin because of its strong penetration character. In conclusion, the residual toxicity of insecticide to honeybee could be affected by the contact and vaporized toxicity of chemical, the residual amounts on the surface of leaves, and the leaf area per unit weight and formulation differences.

• The Korean Journal of Rheology
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• v.11 no.1
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• pp.18-27
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• 1999

Predicting the deformation behaviors of sheets in thermoforming processes has been a daunting challenge due to the strong nonlinearities arising from very large deformations, mold-polymer contact condition and hyperelasticity constitutive equations. Nonlinear numerical analysis is always required to face this challenge especially for realistic processing conditions. In this study a 3-D algorithm and the membrane approximation are developed for thermoforming processes. The constitutive equation is expressed in terms of the 2nd Piola-Kirchhoff stress tensor and the Cauchy-Green deformation tensor. The 2-term Mooney-Rivlin model is used for the material model equation. The algorithm is established by the finite element formulation employing the total Lagrangian coordinate. The deformation behavior and the stress distribution results of 3-D algorithm with various point boundary conditions are compared to those of the membrane approximation algorithm. Also, the slip boundary condition and the no-slip boundary condition are applied for the systems that have molds. Finally, the effect of sheet temperatures on the final thickness distribution is investigated for the ABS material.

• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.419-427
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• 2013

The insecticidal activity of 124 plant essential oils and control efficacy of six experimental spray formulations (SF) containing 0.25, 0.5, 1, 2.5, 5, and 10% of the selected oils was examined against both nymph and adult of the citrus flatid planthopper, Metcalfa pruinosa using direct contact applications (leaf dipping and spray). Reponses varied according to dose (1,000 and 500 mg/L). When exposed at 1,000 mg/L for 24 h using leaf dipping assay, 19 essential oils showed strong mortality (100%) among 124 essential oils screened. At 500 mg/L, 100% mortality was observed in cinnamon technical, cinnamon green leaf, cinnamon #500, cassia tree, citronella java and pennyroyal followed by origanum, thyme white, grapefruit, savory, fennel sweet, aniseed and cinnamon bark showed considerable mortality (93.3-80%) against nymphs of M. pruinosa. The moderate mortality (73.3-60%) was found in thyme red, tagetes, calamus, lemoneucalptus and geranium. Oils applied as SF-10% sprays provided 100 % mortality against adult M. pruinosa. One hundred mortalities were achieved in cinnamon technical at >SF-0.5 formulation, in cinnamon #500, cinnamon green leaf and penny royal at >SF-2.5. To reduce the level of highly toxic synthetic insecticides in the agricultural environment, the active essential oils as potential larvicides could be provided as an alternative to control M. pruinosa populations.

• Microbiology and Biotechnology Letters
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• v.37 no.4
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• pp.399-404
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• 2009

This paper described the formulation of functional cosmetics and evaluation of anti-wrinkle efficacy in clinical test. Cosmetics were formulated with highly purified $\beta$-carotene obtained from the culture broth of recombinant E.coli cells. Edible oil for solubilizing $\beta$-carotene, vitamine E for long-term storage, detergent/stabilizer (2.0%) for the complete formation of oil/water emulsion, dimethicone (0.35%) for good skin care, and sorbitol for skin moisturizer were also added as ingredients. Physical or chemical degradation of formulated products stored at $0^{\circ}C$, $25^{\circ}C$, or $40^{\circ}C$ was not observed for 60-day testing period. In clinical test, 68% of applicants observed wrinkle decrease after 8-week treatment. This result indicates that newly formulated cosmetics have strong potential for improving wrinkle skin care.

• Fisheries and Aquatic Sciences
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• v.17 no.1
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• pp.37-46
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• 2014

Fresh sea squirt meat requires a modified processing and preservation process because it has a short shelf life due to its high moisture content and strong proteolytic enzyme activity. In this study, bottled sea squirt meat prepared in vegetable oil (BSMO) to enhance the consumer acceptability was exposed to ${\gamma}$-ray (Co60, 10 kGy/h) irradiation to extend the shelf life without the use of a heating process. Response surface methodology was used to determine the optimal mixing ratio of BSMO containing 5% dehydrated fresh meat. Texture analysis and nutritional evaluation were also performed on a control and BSMO samples. The volatile basic nitrogen (VBN) content and total cell count were measured to determine the shelf life of irradiated BSMO products during chilled storage at $4^{\circ}C$ for 60 days. According to a panel of 10 trained tasters (aged 20-29 years), the optimal mixing formulation was 80 g meat in 60 mL of mixed vegetable oil (30 mL of olive oil and 30 mL of sesame oil). The highest rated formulation, according to a panel of nine trained tasters (aged ${\geq}30$ years), was 80 g meat in 60 mL of mixed vegetable oil (42 mL of olive oil and 18 mL of sesame oil). Moisture, ash, and protein contents in BSMO did not change significantly (P < 0.05) compared with the control. A higher lipid content ($0.84{\pm}0.23$ to $2.13{\pm}0.61$; P < 0.05) was observed due to the presence of vegetable oil on the surface of BSMO. The vegetable oil raised the hardness, springiness, cohesiveness, gumminess, chewiness, and resilience of BSMO. BSMO products remained edible after 50 days of storage at $4^{\circ}C$ based on the VBN content (BSMO 1: $27.92{\pm}0.96$ mg/100 g, BSMO 2: $24.84{\pm}1.95$ mg/100 g) and total cell count (BSMO 1: $4.60{\pm}0.80$ log CFU/mL, BSMO 2: $3.65{\pm}0.20$ log CFU/mL) when compared with standard levels of VBN (25.00 mg/100 g) and total cell count (5 log CFU/mL), respectively. The results showed that irradiated BSMO products could help to expand the processed seafood market and increase the popularity of seafood among the younger generations.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.3
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• pp.303-321
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• 2011

The availability and efficient use of the feed resources in Asia are the primary drivers of performance to maximise productivity from animals. Feed security is fundamental to the management, extent of use, conservation and intensification for productivity enhancement. The awesome reality is that current supplies of animal proteins are inadequate to meet human requirements in the face of rapidly depleting resources: arable land, water, fossil fuels, nitrogenous and other fertilisers, and decreased supplies of cereal grains. The contribution of the ruminant sector lags well behind that of non-ruminant pigs and poultry. It is compelling therefore to shift priority for the development of ruminants (buffaloes, cattle, goats and sheep) in key agro-ecological zones (AEZs), making intensive use of the available biomass from the forage resources, crop residues, agro-industrial by-products (AIBP) and other non-conventional feed resources (NCFR). Definitions are given of successful and failed projects on feed resource use. These were used to analyse 12 case studies, which indicated the value of strong participatory efforts with farmers, empowerment, and the benefits from animals of productivity-enhancing technologies and integrated natural resource management (NRM). However, wider replication and scaling up were inadequate in project formulation, including systems methodologies that promoted technology adoption. There was overwhelming emphasis on component technology applications that were duplicated across countries, often wasteful, the results and relevance of which were not clear. Technology delivery via the traditional model of research-extension linkage was also inadequate, and needs to be expanded to participatory research-extension-farmer linkages to accelerate diffusion of technologies, wider adoption and impacts. Other major limitations concerned with feed resource use are failure to view this issue from a farming systems perspective, strong disciplinary bias, and poor links to real farm situations. It is suggested that improved efficiency in feed resource use and increased productivity from animals in the future needs to be cognisant of nine strategies. These include priorities for feed resource use; promoting intensive use of crop residues; intensification of integrated ruminant-oil palm systems and use of oil palm by-products; priority for urgent, wider technology application, adoption and scaling up; rigorous application of systems methodologies; development of adaptation and mitigation options for the effects of climate change on feed resources; strengthening research-extension-farmer linkages; development of year round feeding systems; and striving for sustainability of integrated farming systems. These strategies together form the challenges for the future.

• 한국균학회소식:학술대회논문집
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• 2018.05a
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• pp.44-44
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• 2018

Fusarium head blight (FHB) caused by infection with Fusarium graminearum leads to enormous losses to crop growers, and may contaminate grains with a number of Fusarium mycotoxins that pose serious risks to human and animal health. Antagonistic bacteria that are used to prevent FHB offer attractive alternatives or supplements to synthetic fungicides for controlling FHB without the negative effects of chemical management. Out of 500 bacterial strains isolated from soil, Bacillus amyloliquefaciens JCK-12 showed strong antifungal activity and was considered a potential source for control strategies to reduce FHB. B. amyloliquefaciens JCK-12 produces several cyclic lipopeptides (CLPs) including iturin A, fengycin, and surfactin. Iturin A inhibits spore germination of F. graminearum. Fengycin or surfactin alone did not display any inhibitory activity against spore germination at concentrations less than 30 ug/ml, but a mixture of iturin A, fengycin, and surfactin showed a remarkable synergistic inhibitory effect on F. graminearum spore germination. The fermentation broth and formulation of B. amyloliquefaciens JCK-12 strain reduced the disease incidence of FHB in wheat. Furthermore, co-application of B. amyloliquefaciens JCK-12 and chemical fungicides resulted in synergistic in vitro antifungal effects and significant disease control efficacy against FHB under greenhouse and field conditions, suggesting that B. amyloliquefaciens JCK-12 has a strong chemosensitizing effect. The synergistic antifungal effect of B. amyloliquefaciens JCK-12 and chemical fungicides in combination may result from the cell wall damage and altered cell membrane permeability in the phytopathogenic fungi caused by the CLP mixtures and subsequent increased sensitivity of F. graminearum to fungicides. In addition, B. amyloliquefaciens JCK-12 showed the potential to reduce trichothecenes mycotoxin production. The results of this study indicate that B. amyloliquefaciens JCK-12 could be used as an available biocontrol agent or as a chemosensitizer to chemical fungicides for controlling FHB disease and as a strategy for preventing the contamination of harvested crops with mycotoxins.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1245-1252
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• 2003

A starter formulation was developed to substitute a baker's yeast with natural starter when manufacturing bread products. To develop an active starlet, starter was formulated varying with types of wheat flours, level of water contents and various nutrients. Activities of starter were investigated in terms of viable counts of microbes and change of pH and total titratible acidity Domestic wheat flours contain 100 times more number of lactic acid bacteria than yeast regardless of types of wheat flours. The more protein contents in wheat flours, the more stable microbes in starter. This was considered to be the result of buffering effect of wheat proteins. The optimum level of protein content to ensure the activity of starter was more than 12.0%. Optimum level of water content in active starter was 110% based on strong flour. The more water or the less water had the tendency of decreasing viable counts of microbes. Addition of salt and sucrose had increased the activity of starters. However oligosaccharides did not affect the activity of starter. The optimum concentrations of salt and sucrose were 1.0% and 5.0% respectively. Bread with the starter was higher scored than breads with yeast in terms of all the quality and sensory characteristics except their volumes. In conclusion, a starter formulated with strong flour 100%, water 110%, salt 1% and sucrose 5% was considered to have high potential as a substitute of yeast in making natural bread.