• Journal of the Korea Institute of Building Construction
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• v.22 no.6
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• pp.631-640
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• 2022

Recently, construction accidents have occurred due to illegal water addition and insufficient quality control at domestic construction sites. In this study, the void content test method proposed in ASTM C 642 was used to provide a reference guideline for evaluation on the quality control status of cast-in-place structural concrete. For this purpose, simulated structural concrete for coring purpose was prepared in addition to the concrete cylindrical specimens with the same formulation, and the changes in compressive strength, elastic modulus, and void content related to coring were evaluated. According to experimental results, the compressive strength and modulus of elasticity were reduced by coring, which was associated with the generation of microcracks during coring. With respect to void content, the difference in void content between the cylindrical specimen and the cored specimen was up to 1.69%. If this value is used as a correction factor, it is possible to estimate the real void content of the cast-in-place structural concrete. By comparing this with the void content obtained from cylindrical concrete specimens, it is possible to evaluate the quality control status and amount of illegal water addition on the structural concrete.

• Journal of the Korean Electrochemical Society
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• v.25 no.1
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• pp.1-12
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• 2022

Lithium metal is the most promising anode for next-generation lithium-ion batteries due to its lowest reduction potential (-3.04 V vs. SHE) and high specific capacity (3860 mAh/g). However, the dendritic formation under high charging current density remains one of main technical barriers to be used for commercial rechargeable batteries. To address these issues, tremendous research to suppress lithium dendrite formation have been conducted through new electrolyte formulation, robust protection layer, shape-controlled lithium metal, separator modification, etc. However, Li/Li symmetric cell test is always a starting or essential step to demonstrate better lithium dendrite formation behavior with lower overpotential and longer cycle life without careful analysis. Thus, this review summarizes overpotential behaviors of Li/Li symmetric cells along with theoretical explanations like initial peaking or later arcing. Also, we categorize various overpotential data depending on research approaches and discuss them based on peaking and arcing behaviors. Thus, this review will be very helpful for researchers in lithium metal to analyze their overpotential behaviors.

• Research in Plant Disease
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• v.28 no.1
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• pp.1-18
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• 2022

Volatiles exist ubiquitously in nature. Volatile compounds produced by plants and microorganisms confer inter-kingdom and intra-kingdom communications. Autoinducer signaling molecules from contact-based chemical communication, such as bacterial quorum sensing, are relayed through short distances. By contrast, biogenic volatiles derived from plant-microbe interactions generate long-distance (>20 cm) alarm signals for sensing harmful microorganisms. In this review, we discuss prior work on volatile compound-mediated diagnosis of plant diseases, and the use of volatile packaging and dispensing approaches for the biological control of fungi, bacteria, and viruses. In this regard, recent developments on technologies to analyze and detect microbial volatile compounds are introduced. Furthermore, we survey the chemical encapsulation, slow-release, and bio-nano techniques for volatile formulation and delivery that are expected to overcome limitations in the application of biogenic volatiles to modern agriculture. Collectively, technological advances in volatile compound detection, packaging, and delivery provide great potential for the implementation of ecologically-sound plant disease management strategies. We hope that this review will help farmers and young scientists understand the nature of microbial volatile compounds, and shift paradigms on disease diagnosis and management to aromatic (volatile-based) agriculture.

• Journal of Pharmacopuncture
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• v.25 no.3
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• pp.233-241
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• 2022

Objectives: Asthma is a chronic disease, and the demand for herbal medicines in this field has increased in recent years. The new findings highlight the role of the gut-lung axis in the pathophysiology of asthma. Hence, this study will evaluate the safety and efficacy of Glasthma syrup, an herbal formula based on Persian medicine, in improving asthma and regulating intestinal permeability. The formula consists of five herbal ingredients that have anti-inflammatory effects on the respiratory tract, also known as gut tonics. Methods: The study will be conducted as a placebo-controlled, triple-blind, randomized trial. It will consist of a 4-week intervention followed by a 4-week follow-up period. The target sample size is 20 patients with moderate asthma aged 18 to 60 years. Eligible participants will be randomly assigned to either the experimental group or the control group in equal numbers. Patients in the experimental group will take Glasthma syrup (7.5 mL, twice a day), while patients in the control group will take a matching placebo. Both groups will receive a 4-week combination of a long-acting beta2 agonist and a leukotriene modulator as standard of care. Inhaled corticosteroids can be used as rescue medication as needed. Results: The primary outcomes are asthma symptom scale, lung function, and intestinal permeability. Secondary outcomes include quality of life, symptom recurrence rates, and blood tests. A safety assessment will also be conducted during the trial. Conclusion: In this trial, the effects of Glasthma syrup in patients with moderate asthma will be examined. The study will also assess the effects of the formulation on the gut-lung axis by simultaneously monitoring the gut permeability index, asthma symptoms, and lung function.

• Applied Chemistry for Engineering
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• v.33 no.4
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• pp.394-401
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• 2022

The synthesis of 1,2-alkylaminopropanediols (1,2-AAPs) was designed to improve the hydrophilicity of linear 1,2-alkanediols having 10, 12, 14, and 16 carbon atoms in the alkyl chain. 1,2-AAPs were synthesized by reacting 3-monochloro-1,2-propanediol (3-MCPD) with linear alkylamines having 10, 12, 14 or 16 carbon atoms in an ethanol solvent at 40℃ for 2 h. The yield and purity of four types of 1,2-AAPs synthesized were found to be in the range of 51-58% and 85-99%, respectively. The amine salts of four types of 1,2-AAPs were prepared from a purified paste or solid compound by adding an acidic solution (HCl) to pH 7, and then their solubilities and antibacterial effects were tested. 1,2-decylaminopropanediol, 1,2-dodecylaminopropanediol, and 1,2-tetradecylaminopropanediol were all dissolved in water at concentrations of 100%, 50%, and 0.1%, respectively, however 1,2-hexadecylaminopropanediol was not. The antibacterial effect was improved as the length of the alkyl chain increased. As a result of confirming the preservative effect of the lotion (cosmetic formulation) applied with 1,2-AAP for application, it showed very strong antibacterial activity at low concentrations ranging from 0.005% to 0.2%.

• Applied Chemistry for Engineering
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• v.33 no.2
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• pp.179-187
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• 2022

In this study, the synthesis of 1,2-dodecylaminopropanediol (1,2-DDAP) having a 12 carbon chain length and an amine group was designed to improve the preservation and hydrophilicity of 1,2-alkanediol-based compounds. 1,2-DDAP was prepared by reacting dodecylamine (DDA) with 3-monochloro-1,2-propanediol (3-MCPD) in an ethanol solvent at 40 ℃, and its yield and purity were about 56% and 98%, respectively, under a reaction condition of 2 h and a DDA:3-MCPD molar ratio of 1:0.8. The antimicrobial effect of 1,2-DDAP showed the values of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against microorganisms at concentrations of 10 to 100 times lower than those of 1,2-octanediol(1,2-ODIOL) or 1,2-decanediol (1,2-DDIOL). Based on the hydrophilic properties of 1,2-DDAP, mixed preservatives were prepared by adding small amounts of 1,2-ODIOL or 1,2-DDIOL, which are poorly soluble in water, with 1,2-DDAP. Mixed preservatives exhibited an effect of inhibiting microorganisms equal to or greater than that of 1,2-DDAP alone in antimicrobial activity tests. As a result of confirming the preservation effect in lotion (cosmetic formulation) for application, 1,2-DDAP showed similar antimicrobial activity at concentrations of 0.3 to 0.6 times lower than that of 1,2-ODIOL or 1,2-DDIOL. Therefore, it is considered that the use of 1,2-DDAP alone and the mixed use with small amounts of 1,2-ODIOL or 1,2-DDIOL can be a good alternative to preservatives in the product.

• Tunnel and Underground Space
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• v.32 no.5
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• pp.312-326
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• 2022

The generalized Hoek-Brown (GHB) criterion, which is recognized as one of the standard failure conditions for rock mass, is specialized for rock engineering applications and covers a wide range of rock mass conditions. Accordingly, many research efforts have been devoted to the incorporation of this criterion into the stability analysis of rock structures. In this study, the slip-line analysis method, which is a kind of elastoplastic analysis method, is combined with the GHB failure criterion to derive analytical equations that can easily calculate the plastic radius and stress distribution in the vicinity of the circular tunnel. In the process of derivation of related formulas, it is assumed that the behavior of rock mass after failure is perfectly plastic and the in-situ stress condition is hydrostatic. In the formulation, it is revealed that the plastic radius can be calculated analytically using the two respective tangential friction angles corresponding to the stress conditions at tunnel wall and elastic-plastic boundary. It is also shown that the plastic radius and stress distribution calculated using the derived analytical equations coincide with the results of Lee & Pietruszczak's numerical method published in 2008. In the latter part of this paper, the influence of the quality of the rock mass on the size of the plastic zone, the stress distribution, and the change of the tangential friction angle was investigated using the derived analytical equations.

• KIPS Transactions on Software and Data Engineering
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• v.12 no.3
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• pp.117-124
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• 2023

Through reorganization in 2008, The ministry of Agriculture, Food and Rural Affairs integrated management of the food industry by transferred functions which was scattered in the Ministry of Health and Welfare, and established comprehensive policies covering the primary, secondary, and tertiary industries. In the agricultural industry sector, new business concepts such as smart farm and food tech have recently emerged alongside the fourth industrial revolution. In order for the Ministry of Agriculture, Food, and Rural Affairs to develop appropriate policies for the fourth industrial revolution, it is necessary to accurately estimate the size of agricultural and livestock-related businesses. In 2017, the Ministry of Agriculture, Food, and Rural Affairs initiated research for the agriculture, livestock and food industry's special classification, which was approved by the National Statistical Office in 2020. The estimation of the agriculture, livestock and food industry's size based on special classification is crucial because it has a substantial impact on the formulation and significance of policies. In this paper, the appropriate rate was derived from samples extracted from the special classification and the Korean standard industrial classification. Proposed are a method for estimating the population of the agricultural and livestock food industry, as well as a method for calculating the appropriate rate that more accurately reflects the population than the method currently in use.

• Journal of Animal Science and Technology
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• v.64 no.3
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• pp.471-480
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• 2022

This experiment was conducted to determine the maximum dietary energy levels on growth performance and carcass characteristics of White Pekin duck. the Six dietary treatments were formulated based on their apparent metabolizable energy (AME) concentrations from 2,700 to 3,200 kcal/kg with a 100 kcal/kg gap to evaluate the accurate dietary AME requirement to address current knowledge and further issues for fulfilling the genetic potential of meat-type white Pekin ducklings. A total of 432 one-day-old male White Pekin ducklings were randomly allocated into one of six dietary treatments with six replicates (12 birds per pen). The diets were formulated as corn-soybean meal-based diets to meet or exceed the Nutrient Requirement of Poultry specification for meat-type ducks. Growth performance indices (i.e. average daily gain [ADG], average daily feed intake, feed conversion ratio) were measured weekly. Medium body weight (BW) ducklings from each pen were sacrificed to analyze the carcass traits and abdominal fat content on day 21. Obtained data were analyzed to estimate significant effect using the one-way ANOVA of IBM SPSS Statistics (Version, 25). If the p-value of the results were significant, differences in means among treatments were separated by Tukey's post hoc test. Significant differences were then analyzed with a linear and quadratic broken model to estimate the accurate concentration of AME. Ducklings fed higher dietary AME diets increased (p < 0.05) BW, ADG. Ducklings fed higher AME than 2,900 kcal/kg diets increased abdominal fat accumulation and leg meat portion. The estimated requirement by linear plateau method showed from 3,000.00 kcal/kg to 3,173.03 kcal/kg whereas the requirement by quadratic plateau method indicated from 3,100.00 kcal/kg to 3,306.26 kcal/kg. Collectively, estimated dietary requirements exhibit diverse results based on the measured traits and analysis methods. All the estimated requirements in this experiment present higher than previous research, the maximum requirement for the next diet formulation should be selected by the purpose of the diet.

• Advances in aircraft and spacecraft science
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• v.9 no.5
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• pp.415-431
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• 2022

Secondary flows have a huge impact on losses generation in modern low pressure gas turbines (LPTs). At design point, the interaction of the blade profile with the end-wall boundary layer is responsible for up to 40% of total losses. Therefore, predicting accurately the end-wall flow field in a LPT is extremely important in the industrial design phase. Since the inlet boundary layer profile is one of the factors which most affects the evolution of secondary flows, the first main objective of the present work is to investigate the impact of two different inlet conditions on the end-wall flow field of the T106A, a well known LPT cascade. The first condition, labeled in the paper as C1, is represented by uniform conditions at the inlet plane and the second, C2, by a flow characterized by a defined inlet boundary layer profile. The code used for the simulations is based on the Discontinuous Galerkin (DG) formulation and solves the Reynolds-averaged Navier-Stokes (RANS) equations coupled with the Spalart Allmaras turbulence model. Secondly, this work aims at estimating the influence of viscosity and turbulence on the T106A end-wall flow field. In order to do so, RANS results are compared with those obtained from an inviscid simulation with a prescribed inlet total pressure profile, which mimics a boundary layer. A comparison between C1 and C2 results highlights an influence of secondary flows on the flow field up to a significant distance from the end-wall. In particular, the C2 end-wall flow field appears to be characterized by greater over turning and under turning angles and higher total pressure losses. Furthermore, the C2 simulated flow field shows good agreement with experimental and numerical data available in literature. The C2 and inviscid Euler computed flow fields, although globally comparable, present evident differences. The cascade passage simulated with inviscid flow is mainly dominated by a single large and homogeneous vortex structure, less stretched in the spanwise direction and closer to the end-wall than vortical structures computed by compressible flow simulation. It is reasonable, then, asserting that for the chosen test case a great part of the secondary flows details is strongly dependent on viscous phenomena and turbulence.