• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.27 no.4
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• pp.278-285
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• 1991

The authors propose to use the slot system in order to improve of the efficiency for the cambered otter boards. The experiment is divided into 2 parts, one is the efficiency model test, and the other is the visualization model test. The hydrodynamic characteristics of the model otter boards were tested by efficiency model test to measure the shearing, drag force of the models and visualization test using hydrogen bubble method to observe the streak-line and time-line of flow around the models, and milk spout method to observe the separation zone in the wake behind the models. This study tested for 5 models such ad without slot, slot position 0.2C, 0.4C, 0.6C and 0.8C. The results obtained are as follows: \circled1 The maximum C sub(L) of model otter board with slot position 0.6C in attack angle 27$^{\circ}$ was the highest of all models, it's value was 1.59. \circled2 In general, the L/D ratio of the one slot otter boards were 16~28% higher than otter board without slot. \circled3 The slot position 0.6C was better than any other slot position, and it's conformed by visiualization. \circled4 As to the model otter board with slot position 0.6C, flow speed of the back side was faster 1.3 to 1.7 times than in the front side. \circled5 The size of the separated zone in case of the model otter board with 0.6C was smaller than that of any other models.

• Journal of Distribution Science
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• v.14 no.4
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• pp.39-46
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• 2016

Purpose - Recently, as Korean culture and economy develops, Seoul has become a world-famed city. In Seoul, many special grade hotels have been constructed in order to accommodate many tourists from China, Japan and many other Asian countries. And the hotels entered into competition among themselves. Thus many changes are accelerated due to their mutual competition and manpower problems. In this situation, the role of higher officers above all is thought to be very important in order to enhance the management result and to make preparations for the kernel ability of the organization. Research design, data and methodology - This study was intended to verify how the leadership of the higher officers based on trust affects the job satisfaction of employees of the organization. In order to achieve the purpose of this study, some study models and hypotheses have been established through theoretical examinations. The subjects of this study were centered on the constituents of C-Hotel, M-Hotel, and D-Hotel. 200 questionaries were distributed and 190 questionaries were collected and thus the collection ratio was 91 percent. 8 questionaries which were regarded to be insincere or hard to analyzed were excluded. Finally, 182 questionaries were used for analyzing the factors and trust. For the purpose of the verification of hypotheses, structural equation was used. In order to verify the mediating effect of trust between the relationship of emotional leadership and job satisfaction, 'Three-step Mediated Regression Analysis by Baron & Kenny(1986) was utilized. The four hypotheses for this study are as follows: First, emotional leadership will have a meaningful influence on trust in the affirmative. Second, trust will have a meaningful influence on job satisfaction in the affirmative. Third, trust will play a mediating role in the relationship of emotional leadership and job satisfaction. Result - First, the emotional leadership and trust was found to effect a positive effect. Second, the trust and job satisfaction was found on a positive effect on job satisfaction. Third, the emotional leadership and job satisfaction was found to positive effect on job satisfaction. Fourth, the trust in the relationship between emotional leadership and job satisfaction was found that the partial mediating effect. Especially, in the case of the business of hospitality, human services as well as material resources become its keynote, and we can safely say that the degree of dependence toward human resources is very high. Accordingly, the leaders should display their leadership on the basis of abundant emotional and intellectual faculties so that they can grasp, understand and admit the diverse views of value and emotion of the organization constituents and that they can form emotional leadership. On the basis of the analysis results of the verification of hypotheses, some suggestions and uppermost limit of this study have been presented for further study.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.5
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• pp.467-472
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• 1991

In order to investigate the changes of lipid ingredient and fatty acid content in flint corn by a growth process, total lipids from flint corn(Zea may l.) were extracted, purified and fractionated into three lipid classes (neutral lipid ; NL, glycolipid ; GL, phospolipid ; PL) by silicic acid column chromatography (SACC). Non-polar lipid ingredients and fatty acid contents were determined by thin layer chromatography (TLC) and gas chromatography (GC). And non-polar lipid ingredients were quantitatived by TLC scanner. The crude oil among proximare composition increased 2.74% to 4.43% and NL and PL were fractionated by SACC increased 48.5% to 86.02%, 1.01% to 2.73%, respectively. But GL decreased 50.4% to 11.25%. Neutral lipid ingredients identified monoglyceride, were 1.1~3.7%, 11.9~16.1%, 2.3~4.2%, 16.7~21.5% and 58.5~63.6%, respectively. The major fatty acids of NL were linoleic (48.9~61.0%), oleic(22.3~34.2%), palmitic (10.3~11.7%) acids and stearic, linolenic acids were also detected as minor components. The ratio of total unsaturated fatty acid to total saturated fatty acid presented a higher percentage of 5.87~6.34. The physico-chemical characteristics of flint corn lipids were presented as specific gravity presented 0.920, refractive index 1.468, saponification value 191.2, unsaponificable matter 0.97%, acid value 0.58 and iodine value 124.6, respectively.

• Bulletin of the Korean Chemical Society
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• v.17 no.9
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• pp.794-798
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• 1996

Solid solutions of the nonstoichiometric Dy1-xSrxCoO3-y system with the compositions of x=0.00, 0.25, 0.50, 0.75, and 1.00 have been synthesized by the solid state reaction at 1000 ℃ under atmospheric air pressure. The crystallographic structures of the solid solutions are analyzed by the powder X-ray diffraction patterns at room temperature. The analyses assign the compositions of x=0.00 and 0.25 to the orthorhombic system with space group of Pbnm/D2h16, the compositions of x=0.50 and 0.75 to the tetragonal system like a typical SrCoO2.86, and the composition of x=l.00 or SrCoO2.50 to the brownmillerite type system with space group of I**a. The reduced lattice volumes increase with x value due to the larger radius of Sr2+ ion than that of Dy3+ ion. The mole ratio of Co4+ ion to total Co ion with mixed valence state between Co3+ and Co4+ ions at B sites or τ value has been determined by an iodometric titration. All the samples except for the DyCoO3 compound show the mixed valnce state and thus the composition of x=0.50 has the maximum τ value in the system. The oxygen vacancies increasing with x value are randomly distributed over the crystal lattice except for the composition of x=l.00 which have the ordering of the oxygen vacancies. The nonstoichiometric chemical formulas of the Dy1-xSrxCo3+1-τCo4+τO3-(x-τ)/2 system are formulated from the x, τ, and y values. The electrical conductivity in the temperature range of 100 to 900 K increases with τ value linearly because of positive holes of the Co4+ ions in π* band as a conducting carrier. The activation energy of the x=0.50 as Ea=0.17 eV is minimum among other compouds. Broad and high order transition due to the overlap between σ* and π* bands broadened by the thermal activation is observed near 1000 K and shows a low temperature-semiconducting behavior. Magnetic properties following the Currie-Weiss law show the low to high spin transition in the cobaltate perovskite. Especially, the composition of x=0.75 presents weak ferromagnetic behavior due to the Co3+-O2--Co4+ indirect superexchange interaction.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.4
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• pp.422-429
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• 2018

To make students recognize the danger of fire smoke that may occur in ships and to improve the response capability, spaces for safety educ ation were built inside the training ship, and scenarios were developed. This study is an analysis of the movement characteristics of the students acquire d under each scenario. Followings are the summary of the analysis results. In the non-smoke environments, there was no difference in the velocity of escape movement between the case of without block on the familiar route and the case of with unexpected block. However, when the indoor was filled with smoke, the visibility became very low because of the smoke density and the average velocity was 62.5 % slower than the case where it was not. Regardless of the scenarios, the average equivalent velocity on the complex path was faster than the simple straight path, and the standard deviation was smaller. Under the smoke-fullfilled environment, although the relative velocity probability distributions of the complex passage and the entire passag e are very similar, the inter-individual fluctuation of the relative velocity ratio of the complex passage to that of the entire passage was very large. On the other hand, equivalent velocity could be expressed by the logarithmic function of the visibility. Also, as the tension of the students increased, the equivalent velocities were accelerated on all scenarios.

• Journal of Sasang Constitutional Medicine
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• v.32 no.3
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• pp.33-45
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• 2020

Object Although Taeeum and Soyang constitutional types have bigger body shapes and higher body mass index values than those with the Soeum, the relationship between the Sasang constitutional type and bone mass density is controversial and the association of osteopenia and osteoporosis remains unknown. Therefore, we investigated the relationship between bone mineral density, osteopenia, and osteoporosis according to Sasang constitutional type. Methods A total of 2,508 participants were included in this study. Among the study participants, 1,396 had Taeeum type, 276 had Soeum type, and 836 had Soyang type, respectively. The relationships to bone mass density, osteopenia, and osteoporosis in those with Sasang constitutional type were estimated using logistic and linear regression models. Results Bone mass density was significantly higher in the order of Taeeum, Soyang, and Soeum group (p < 0.01). Soeum group in comparison with Taeeum or Soyang group was significantly associated with a high odds ratio for osteopenia and osteoporosis except in the hip and femoral neck in the comparison of Taeeum and Soeum group (p < 0.01). Moreover, the bone mass density of Soeum group decreased more rapidly as the age increased when compared with Taeeum and Soyang group. Conclusions Our findings may contribute to the early prevention and management of high-risk individuals with poor bone mass density, osteopenia, and osteoporosis using Sasang constitution medicine.

• Journal of The Korean Society of Clinical Toxicology
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• v.12 no.2
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• pp.77-84
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• 2014

Purpose: Carbamate insecticides are potent cholinesterase inhibitors capable of causing severe cholinergic toxicity. Use of carbamate rather than organophosphate insecticides has been increasing. Compared with organophosphate poisoning, relatively few studies have investigated carbamate-associated acute pancreatitis. We investigated general characteristics and pancreatitis of carbamate poisoning and the predictors, among those readily assessed in the emergency department. Methods: We performed a retrospective review of consecutive patients, aged over 18 years, who were admitted between January 2008 and April 2012 to an emergency department (ED) of an academic tertiary care center for treatment of carbamate poisoning. Patients who exhibited poisoning by any other material, except alcohol, were excluded. After application of exclusion criteria, patients were divided according to carbamate-induced pancreatitis and non-pancreatitis groups. Results: A total of 41 patients were included in this study. Among these 41 patients, the prevalence of acute pancreatitis was 36.6% (15 patients). Initial blood chemistry tests showed a statistically higher glucose level in the pancreatitis group, compared with the non-pancreatitis group (222, IQR 189-284 vs. 137, IQR 122-175 mg/dL, P<0.05). Regarding clinical courses and outcomes, a significantly higher proportion of patients developed pneumonia [10 (66.7%) vs. 6 (23.1%), P<0.05] and had a longer hospital stay (7 days, IQR 6-12 vs. 5 days, IQR 2-11, P<0.05), but no difference in mortality, in the pancreatitis group vs. the non-pancreatitis group. In multivariate analysis, the initial glucose was showing significant association with the presentation of carbamate-induced acute pancreatitis (odds ratio 1.018, 95% confidence interval 1.001-1.035, P<0.05). Conclusion: Carbamate-induced acute pancreatitis is common, but not fatal. Initial serum glucose level is associated with acute pancreatitis.

• Food Science and Preservation
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• v.12 no.4
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• pp.361-366
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• 2005

An electronic nose equipped with metal oxide sensor(MOS) was used for investigating the quality of reconstitute orange juice added different recoverable oil(cold pressed valencia oil) contents during 21 days of storage at $4^{\circ}C$. Quality changes in orange juice was described in terms of the sensitivity(${\Delta}R_{gas}/R_{air}$) of the sensors. Principal component analysis(PCA) was carried out using data obtained from twelve metal oxide sensors. The flavor of orange juice contained with the different recoverable oil contents($0.01\%{\sim}0.05\%$) was separated in PCA plot, in which the first principal component score was correlated with the content of recoverable oil. As storage periods prolonged, no significantly different sensitivity score of orange juice was observed in electronic nose. The content of recoverable oil in orange juice was reduced rapidly within 14 days, and then the decreasing ratio was slow on the next 7 days during storage at $4^{\circ}C$. The sensory score for overall and orange flavor of orange juice added $0.03\%$ recoverable oil was decreased during the 14 days and then rapidly dropped next 7 days of storage at $4^{\circ}C$.

• Journal of Adhesion and Interface
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• v.22 no.3
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• pp.98-105
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• 2021

In this study, we prepared a silver nanoparticle transferable adhesive composition with transparency and adhesive properties using UV-curable urethane acrylate containing silane groups. The urethane-based adhesive composition was applied between the Ag/PET film in which silver nanoparticles were patterned on PET and the PC film to be transferred. Immediately after UV-curing with UV, PET was removed to complete the manufacture of Ag/PC film. UV-curable urethane acrylate containing silane groups was synthesized using polycaprolactone diol (PCL), isophrone diisocyanate (IPDI), 2-hydroxyethyl methacrylate (HEMA), and (3-aminopropyl) triethoxysilane (APTES). The silane group of APTES can improve interfacial adhesion by reacting with the specially treated silver nanoparticle surface of the Ag/PET film. In addition, we improved the adhesion between silver nanoparticle and PC film by mixing UV-curable urethane acrylate containing a silane group and a functional acrylic diluent used as a diluent. We analyzed the synthesis process of urethane acrylate using FT-IR, and compared the adhesive properties, optical properties, and transfer properties according to the molar ratio of APTES and the acrylic diluent composition. As a result, the best transfer properties were confirmed in the adhesive composition prepared under the conditions of PUA2S1_0.5.

• Journal of the Korean Applied Science and Technology
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• v.38 no.2
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• pp.476-487
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• 2021

To prepare acrylic resin coatings containing 70% of solids, we used n-butyl methacrylate(BMA), methyl methacrylate(MMA), 2-hydroxyethyl methacrylate(2-HEMA), and acetoacetoxyethyl acrylate(AAEA), caprolactone acrylate(CLA) as raw materials, the glass transition temperature(T_g) of acrylic copolymer was adjusted around 50 ℃. The viscosity and molecular weight of the acrylic resins was increased with increasing OH values. Di-tert-amyl peroxide was found to be the suitable initiator to get high-solids acrylic resins. The optimum reaction conditions found in the study are 5 wt% of initiator, 4 wt% of chain transfer agent, 4 hrs of dropping time, and 140 ℃ of reaction temperature. The structure of the synthesized resins were characterized by FT-IR and ¹H-NMR spectroscopy. Number average molecular weight of 1900~2600 and molecular wight distribution of 1.4~2.1 were obtained. Crosslinked acrylic urethane clear coatings were obtained by curing reaction between the synthesized acrylic resins and hexamethylene diisocyanate trimer(Desmodur N-3300), the equivalent ratio of NCO/OH was 1.2/1.0. The physical properties from the following studies were carried out: viscosity(Zahn cup #2), adhesion, drying time, pot-life, pensil hardness, and 60° specular gloss. Various properties of the acrylic urethane clear coatings were also evaluated on the coating specimens. Adhesion property to a substrate, drying time, pot-life, pencil hardness, and 60° specular gloss of prepared paint showed quite good properties. Futhermore, prepared paint containing 10% of CLA showed quite good properties for adhesion, low viscosity and high hardness.