• Journal of Life Science
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• v.32 no.6
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• pp.482-490
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• 2022

Sarcopenia, a geriatric and multifactorial syndrome characterized by progressive systemic skeletal muscle disorder, may be associated with many comorbidities. Sarcopenia caused by a decrease in muscle mass and muscle strength is accompanied by the aggravation of various pathological conditions, and as life expectancy increases, its prevalence will continue to increase in the future. During the aging process, chronic oxidative stress and increased inflammatory responses act as major contributors to skeletal muscle loss. In addition, disruption of autophagy and apoptosis signals associated with dysfunction of mitochondria, which are essential for energy metabolism, accelerates the loss of muscle proteins. The pharmacological effect of cordycepin, a major physiologically active substance in the genus Cordyceps, which has been widely used for the prevention and treatment of various diseases for a long time, is directly related to its antioxidant and anti-inflammatory actions. In this review, we present the correlation between apoptosis, autophagy, protein catabolism, and satellite cell activity important for muscle regeneration using cordycepin for the prevention and treatment of sarcopenia. Although there have been few studies so far on the use of cordycepin for sarcopenia, previous studies suggest that cordycepin may contribute to inhibiting the age-related weakening of mitochondrial function and blocking the breakdown of muscle proteins. In addition, the protective effect of cordycepin on muscle cell damage is considered to be closely related to its antioxidant and anti-inflammatory activities. Therefore, it is considered that more continuous basic research is needed, focusing on the molecular biological mechanism of cordycepin, which is involved in the anti-aging of muscle cells.

• Journal of the Korea Organic Resources Recycling Association
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• v.29 no.4
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• pp.47-54
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• 2021

In this study, the performance of a honeycomb-type hydrogen oxidation catalyst to remove hydrogen in a hydrogen economy society to secure leaking hydrogen. The Pd/TiO₂ catalyst was prepared based on a liquid phase reduction method that is not exposed to a heat source, and it was showed through H₂-chemisorption analysis that it existed as very small active particles of 2~4 nm. In addition, it was found that the metal dispersion decreased and the active particle size increased as the reduction reaction temperature increased. It was meant that the active metal particle size and the hydrogen oxidation performance were in a proportional correlation, so that it was consistent with the hydrogen oxidation performance reduction result. The prepared catalyst was coated on a support in the form of a honeycomb so that it could be applied to the hydrogen industrial process. When 20 wt% or more of the AS-40 binder was coated, oxidation performance of 90% or more was observed under low-concentration hydrogen conditions. It was showed through SEM analysis that long-term catalytic activity can be expected by enhancing the adhesion strength of the catalyst and preventing catalyst desorption. It is a basic research that can secure safety in a hydrogen society such as gasification, organic resource, and it can be utilized as a system that can respond to unexpected safety accidents in the future.

• Journal of Service Research and Studies
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• v.13 no.3
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• pp.147-159
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• 2023

This study is a study to develop a model for measurement and processing of experience data, which is emerging as a core value in quality management of medical services. In the theoretical background, a literature study was conducted on the importance of experience in medical service, measurement and processing of experience data, and realization of patient-centeredness. Based on these literature and theoretical background research results, operational definitions were performed for the following four research variables, and statistical tests were conducted. Hypothesis 1 is the effect of measuring experience data from the perspective of three factors on persona modeling, Hypothesis 2 is the effect of persona modeling on service blueprint visualization, Hypothesis 3 is the effect of service blueprint visualization on realization of patient-centeredness, and Hypothesis 4 is persona modeling This is the effect that modeling has on the realization of patient-centeredness. After data-based testing of factor analysis, reliability analysis, and correlation analysis, all four hypotheses were adopted as a result of verification using regression analysis. In conclusion, in an era where it is difficult to recognize the value of having only good medical staff and medical equipment in hospitals, it was possible to grasp the meaning that what kind of medical service experience is continuously obtained is more important to patients than the effectiveness of medical staff and medical equipment. In the era of the service economy, the core of hospital service competitiveness is providing attractive experiences, which is the real strength of hospitals, so the measurement and processing of experience data, which is the subject of this study, will have an important meaning in realizing patient-centeredness and realizing smart hospitals.

• The Korean Journal of Franchise Management
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• v.8 no.4
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• pp.7-19
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• 2017

Purpose - The purpose of this study is to investigate the effect of model attractiveness on brand attitude and purchase intention, and examine whether product-model match-up plays a moderating role in the relationship between model attractiveness and brand attitude and purchase intention. The model attractiveness is consist of psychological and physical attractiveness of the model. The authors investigate how product-model match-up influence the strength of the relationship between model attractiveness - brand attitude and purchase intention. The purpose of this is to test whether product-model match-up influence the form and effectiveness of a model attractiveness on brand attitude and purchase intention and suggest the effective and efficient methods in the model selection strategies to increase advertising effectiveness based on the results of this study. Research design, data, and methodology - The experimental design for this study was the between subject design based on 2 group of the psychological attractiveness(high vs. low) × product-model match-up(high vs low) and 2 group of the physical attractiveness(high vs. low) × product-model match-up(high vs low). And a preliminary investigation was conducted to develop experimental stimuli through manipulation check to enhance the external validity of experimental research. The attractiveness of the model and product-model match-up are independent variables and manipulative variables in presentation of experimental stimuli. The self-administered methode experiment was conducted on 300 subjects in four groups constructed according to the independent variables. Result - The findings provide partial support for a moderator for product-model match-up on the model attractiveness - brand attitude and purchase intention. First, the influence of psychological attractiveness and physical attractiveness on brand attitude and purchase intention was shown significant. Also, it was found that the average value of brand attitude and purchase intention according to psychological attractiveness was significantly higher than the average value of brand attitude and purchase intention according to physical attractiveness in additional analysis. Second, the average value of brand attitude and purchase intention were higher when product - model match-up was high in both high and low psychological attractiveness and physical attractiveness of the model. However, in the case of psychological attractiveness, the correlation effect with product - model match-up was significant, but in the case of physical attractiveness, it was not significant. Conclusions - The results of this study suggest that the attractiveness factor should be considered in selecting the ad model by verifying the effect of the attractiveness of the model on the advertising effect. In particular, this study has great significance both academically and practically in terms of suggesting such implications that the advertising effect of psychological attractiveness and physical attractiveness may be different depending on the product type by additional analysis.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6C
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• pp.321-329
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• 2008

In this study, a series of column test as a way in order to make up for the weakness point of the conventional acceleration method were conducted to both propose the suction board drain method and grapes the specific improvement character of this method as a result of a sort of plastic drain board and a phase of vacuum pressure conditions. On this occasion, the study focused on computing the effective factors of the fittest Suction board drain method affected by each condition through confirming the settlement generated during the test, the water content reduction and stress increase effect occurred arising from the test, and the ratio of consolidation related to the improvement period. In accordance with the shape of core and that whether the core is attached to the filter(pocket or adhesion), the castle type of adhesion and the column type of pocket are more efficient than the others as a consequence of the test to find out the improvement effect depending on each drainage such as a castle type, coil type, harmonica type, column type of pocket and a castle of the adhesion. In case of the step suction pressure, the shorter the period of $-0.8\;kg/cm^2$ as a final step of the suction pressure is, the better the improvement is. In addition, the correlation between degree of consolidation per each suction pressure level and duration of application was drawn as a curve and the point of inflection on this curve was provided to determine the duration period to maximize the consolidation.

• Health Policy and Management
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• v.33 no.3
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• pp.311-324
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• 2023

Background: Long-term care insurance for the elderly has been stably established along with the quantitative expansion of long-term care facilities. Indeed, the need for a paradigm about human rights-based service approach is being raised throughout society from a service perspective. Therefore, this study aimed to analyze the association between elderly human rights awareness and quality of service by considering human rights education as a moderate variable. Methods: This study conducted surveys with 138 caregivers working in long-term care facilities located in Seoul and Gangwon. General characteristics, awareness of human rights, and the level of service quality were examined using descriptive statistics, frequency analysis, and correlation analysis. And multi-variable linear regression with a hierarchical framework was employed. These analyses were performed using IBM SPSS ver. 25.0. Results: Of the 138 caregivers, 97.1% were female, 87.7% were more than 50 years old, and most of their education level was high-school graduates. Their length of employment ranged from more than 5 years to less than 10 years. The level of awareness regarding elderly human rights of the elderly was below normal (mean=2.21), but the quality of service was high (mean=4.21), and the need for human rights education was also high (mean=4.28). Among the general characteristics, the length of employment was significantly associated with awareness of elderly human rights. Moreover, political rights awareness, included as sub-domains of human rights, was positively associated with quality of service. However, the moderating variable, human rights education, was not significantly associated with the quality of service. Conclusion: In this study, human rights education, as a moderating variable, did not have a statistically significant effect on caregivers' human rights awareness in relation to service quality. This finding is inconsistent with previous research results. These results can be explained by the fact that the frequency of education in long-term care facilities was a significant factor in the practice of protecting the human rights of the elderly. Therefore ongoing encouragement for the frequency of current human rights education and improvements in the educational approach appear to be necessary. In addition, these findings reveal the need for strength of education policies and effective in-depth research about human rights and quality of service to respect the human rights of the elderly.

• Steel and Composite Structures
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• v.50 no.6
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• pp.705-720
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• 2024

Analyzing the collapse behavior of thin-walled steel structures holds significant importance in ensuring their safety and longevity. Geometric imperfections present on the surface of metal materials can diminish both the durability and mechanical integrity of steel shells. These imperfections, encompassing local geometric irregularities and deformations such as holes, cavities, notches, and cracks localized in specific regions of the shell surface, play a pivotal role in the assessment. They can induce stress concentration within the structure, thereby influencing its susceptibility to buckling. The intricate relationship between the buckling behavior of these structures and such imperfections is multifaceted, contingent upon a variety of factors. The buckling analysis of thin-walled steel shell structures, similar to other steel structures, commonly involves the determination of crucial material properties, including elastic modulus, shear modulus, tensile strength, and fracture toughness. An established method involves the emulation of distributed geometric imperfections, utilizing real test specimen data as a basis. This approach allows for the accurate representation and assessment of the diversity and distribution of imperfections encountered in real-world scenarios. Utilizing defect data obtained from actual test samples enhances the model's realism and applicability. The sizes and configurations of these defects are employed as inputs in the modeling process, aiding in the prediction of structural behavior. It's worth noting that there is a dearth of experimental studies addressing the influence of geometric defects on the buckling behavior of cylindrical steel shells. In this particular study, samples featuring geometric imperfections were subjected to experimental buckling tests. These same samples were also modeled using Finite Element Analysis (FEM), with results corroborating the experimental findings. Furthermore, the initial geometrical imperfections were measured using digital image correlation (DIC) techniques. In this way, the response of the test specimens can be estimated accurately by applying the initial imperfections to FE models. After validation of the test results with FEA, a numerical parametric study was conducted to develop more generalized design recommendations for the stainless-steel shell structures with the initial geometric imperfection. While the load-carrying capacity of samples with perfect surfaces was up to 140 kN, the load-carrying capacity of samples with 4 mm defects was around 130 kN. Likewise, while the load carrying capacity of samples with 10 mm defects was around 125 kN, the load carrying capacity of samples with 14 mm defects was measured around 120 kN.

• Tuberculosis and Respiratory Diseases
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• v.44 no.1
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• pp.93-103
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• 1997

Background : Malnutrition is a common finding in patients with chronic obstructive pulmonary disease, especially in the emphysema group. Although the mechanism of malnutrition is not confirmed, it is believed to be a relative deficiency caused by hypermetabolism due to increased energy requirements of the respiratory muscles, rather than a dietary deficiency. Malnutrition in chronic obstructive pulmonary disease is not a merely coincidental finding. It is known that the nutritional status correlates with physiologic parameters including pulmonary function, muscular power, and exercise performance, and is one of the important and independent prognostic factors of the disease. Methods : Patients with chronic obstructive pulmonary disease Yongdong Severance Hospital from May, 1995 to March, 1996 and age-matched healthy control group were studied. Survey of nutritional intake, anthropometric measurements and biochemical tests were done to assess nutritional status. Relationship between nutritional status and FEV1 (forced expiratory volume at one second), which was a significant functional parameter, was assessed. Results : 1) The patient group was consisted of 25 males with mean age of 66.1years and FEV1 of $42{\pm}14%$ of predicted values. The control group was consisted of 26 healthy males with normal pulmonary function, whose mean age was 65.0 years. 2) The ratio of calorie intake/calorie requirement per day was $107{\pm}28%$ in the patient group, and $94{\pm}14%$ in the control group, showing a tendency of more nutritional intake in patient group(B=0.06). 3) There were significant differences between the patient group and control group in percent ideal body weight(92.8% vs 101.6%, p=0.024), body mass index($20.0kg/m^2$ VS $21.9kg/m^2$, p=0.015), and handgrip strength(29.0kg vs 34.3kg, p=0.003). However, there were no significant differences in triceps skinfold thickness, mid-arm muscle circumference, albumin, and total lymphocyte count between two groups. Percentage of underweight population was 40%(10/25) in the patient group, and 15%(4/26) in the control group. 4) The percent ideal body weight, triceps skinfold thickness, and mid-arm muscle circumference had significant correlation with FEV1. Conclusion : The patients with chronic obstructive pulmonary disease showed significant depletion in nutritional parameters such as body weight and peripheral muscle strength, while absolute amount of dietary intake was not insufficient. Nutritional parameters were well correlated with FEV1.

• Applied Chemistry for Engineering
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• v.7 no.5
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• pp.877-887
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• 1996

The ideal membranes for membrane-covered oxygen probes system should be selectively permeable for oxygen and chemically inert, and have good mechanical strength. Polysulfone(PSf) was selected to develop the membrane for membrane-covered oxygen electrodes system. PSf membranes have properties such as good reproducibility, good mechanical strength, chemical inertness, and high heat resistance. PSf membranes were cast from polymer solution on the glass plate at constant temperature, and casting solvents used were tetrahydrofuran(THF), methylene chloride, and N-methyl-2-pyrrolidone(NMP). Tricresyl phosphate(TCP) as plasicizer was added to PSf to increase the softness of membrane. The permeation characteristics were observed for pure oxygen and nitrogen through pure PSf membranes by variable volume method and membrane-covered electrode system. The permeability coefficients of oxygen and nitrogen measured by variable volume method were slightly decreased with increasing of upstream pressure. The permeation properties of PSf membrane using methylene choride as casting solvent were not affected by the PSf amount of polymer solution. The permeability coefficients of oxygen and nitrogen for PSf membrane containing TCP were very slightly lower than those for pure PSf membrane, but ideal separation factors were slightly higher. The flexibility of PSf membrane containing 2wt% TCP was better than that of pure PSf membrane. It was expected that this increase in flexibility would solve the difficulty of fixing the membrane to the cathode. The membrane-covered oxygen probes system was composed of anode, cathode and electrolyte. The type of the anode was Ag/AgCl half-cell, that of cathode was Ag, and the electrolyte was 4N KCl solution. The result of sampled current voltametry for PSf membrane showed the plateu region at -0.3V~-1.0V. The correlation coefficient of oxygen partial pressure versus current for PSf membrane was relatively high, 0.99949. It was concluded that PSf membrane was the good candidate for the membrane-covered oxygen probes system.

• Journal of Bio-Environment Control
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• v.22 no.3
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• pp.284-290
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• 2013

This study analyzed the geometric, compressive, cutting and friction properties of oriental melons in order to design a gripper capable of soft handling and a cutter for cutting oriental melon vine among the end effector of oriental melon as a preliminary step for developing the end effector of the robot capable of harvesting oriental melons in protected cultivation. As a result, the average length, diameter at the midpoint, weight, volume and roundness of the oriental melons were 108 mm, 70 mm, 188 g, 333 mL and 3.8 mm. Nonlinear regression analysis was performed on the equation $W=L^a{\times}D_2^b$ with variation of the length (L) and diameter (D2) of the weight (W) of the oriental melons. As a result, it was shown that there was a correlation between a of 2.0279 and b of -0.9998 as a constant value. The average diameter of the oriental melon vine was 3.8 mm, and most vines were distributed within a radius of 5 mm from the center. The average yield value, compressive strength and hardness of the oriental melons were $36.5N/cm^2$, $185.7N/cm^2$ and $636.7N/cm^2$, respectively. The average cutting force and shear strength of the oriental melon vines were $2.87{\times}10^{-2}\;N$ and $5.60N/cm^2$, respectively. The maximum friction coefficient of the oriental melons was rubber of 0.609, followed by aluminium of 0.393, stainless steel of 0.177 and teflon of 0.079. It was considered possible to apply it to the size of the gripper and cutter, turning radius, dynamics of drive motor and selection of materials and their quality in light of the position error and safety factor according to the movement when designing end effector based on the analyzed data.