• ALGAE
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• v.31 no.3
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• pp.243-256
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• 2016

Concerns about how ocean acidification will impact marine organisms have steadily increased in recent years, but there is a lack of knowledge on the responses of macroalgae. Here, we adopt an outdoor continuous-flowing mesocosm system designed for ocean acidification experiment that allows high CO₂ conditions to vary with natural fluctuations in the environment. Following the establishment of the mesocosm, five species of macroalgae that are common along the coast of Korea (namely Ulva pertusa, Codium fragile, Sargassum thunbergii, S. horneri, and Prionitis cornea) were exposed to three different CO₂ concentrations: ambient (×1) and elevated CO₂ (2× and 4× ambient), over two-week period, and their ecophysiological traits were measured. Results indicated that both photosynthesis and growth exhibited species-specific responses to the different CO₂ concentrations. Most notably, photosynthesis and growth increased in S. thunbergii when exposed to elevated CO₂ conditions but decreased in P. cornea. The preference for different inorganic carbon species (CO₂ and HCO₃⁻), which were estimated by gross photosynthesis in the presence and absence of the external carbonic anhydrase (eCA) inhibitor acetazolamide, were also found to vary among species and CO₂ treatments. Specifically, the two Sargassum species exhibited decreased eCA inhibition of photosynthesis with increased growth when exposed to high CO₂ conditions. In contrast, growth of U. pertusa and C. fragile were not notably affected by increased CO₂. Together, these results suggest that the five species of macroalgae may respond differently to changes in ocean acidity, with species-specific responses based on their differentiated photosynthetic acclimation. Understanding these physiological changes might allow us to better predict future changes in macroalgal communities in a more acidic ocean.

• CELLMED
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• v.6 no.1
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• pp.6.1-6.6
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• 2016

Polycystic Ovarian Syndrome (PCOS) has now become more common in occurrence in women of reproductive age, particularly in urban and semi-urban population in India. So there is a need to investigate this phenomenon taking into consideration various aspects including possible treatment method to ameliorate/eradicate this syndrome, which has far reaching socio-economic impact and consequences, in view of infertility and irregular menstrual cycles frequently associated with this syndrome. Homeopathy is a branch of traditional alternative medicine which is gaining popularity in India and some other developing countries, as also in some of the developed countries in Europe. With this background scenario, we have made an attempt to treat cases of confirmed PCOS and tried to compare the relative efficacy of two potentized homeopathic drugs, namely, Lycopodium clavatum (Lyco) and Calcarea carbonica (Calc), most frequently used by homeopathic practitioners, selecting different potencies of the drugs, depending on condition/guiding symptom(s) of the patients. While the main focus was pointed on total/partial removal of cysts, data pertaining to different PCOS associated symptoms were also compared for the sake of learning if the two drugs had differential effects on these symptoms also. The study parameters in this investigation included: regularity/irregularity of menstrual cycle, presence/absence of acne, hirsutism, male type alopecia, acanthosis nigricans, body/mass index (BMI) and waist-hip ratio. Overall results provided clear evidences that both these homeopathic drugs had great ameliorating effects on PCOS, although each drug had a little different effect in respect of the individual parameters of this study.

• The Journal of the Acoustical Society of Korea
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• v.37 no.5
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• pp.309-316
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• 2018

Various studies have been conducted to improve the BSR (Buzz, Squeak, Rattle) noise generated irregularly while the vehicle is running. In vehicle, When an external force such as vibration or force flows into the contact surface, BSR noise is generated at the contact surfaces of nearby components. In this paper, BSR conceptually explain the kind of noise generation mechanisms and the basic principles of generation, which have been proven by observing and improving noise phenomena in automobiles over the last 10 years. Through this, it is expected that researchers who want to study BSR related improvement research not only in automobiles but also in other industries, It will be able to understand the BSR phenomenon and provide a framework for thinking out improvement ideas and to carry out further research.

• The Journal of Information Systems
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• v.17 no.4
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• pp.99-127
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• 2008

E-learning becomes an important part of education these days in Korea. Students had no choice but to accept the e-learning when the e-learning was used as a supplementary learning tool within a traditional class or a stand-alone distance education. This study focuses on the students' intention of e-learning acceptance for voluntary studies. In voluntary study, students have the rights to adopt the e-learning or not for their personal study. We used individual characteristics as the external variables of TAM to explain user acceptance of e-learning for voluntary studies and examined the effect of individual characteristics on user's beliefs. Research model and nine hypotheses were set up to identify the relationships among these variables based on investigations of previous researches. The theoretical model is tested with questionnaires from 420 users who accept e-learning for voluntary studies. We tested the measurement and research models by applying a structural equation modeling(SEM) approach, using the AMOS 5.0. Overall, the results provided support for the model as explaining acceptance of an e-learning system. Most path coefficients in the research model were found statistically significant. The results showed usefulness and enjoyment and subject norm were the factors affecting attitude of students using e-learning. In addition, usefulness and subject norm were the factors affecting intention of students using e-learning. The results show innovation and self-efficacy have a significant impact on user's perception of ease of use. Self-efficacy also have significant effects on user's perception of usefulness.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.10
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• pp.1002-1010
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• 2015

Natural gas hydrates are newly emerging as an environment-friendly source of energy to substitute for fossil fuels in the 21stcentury.NGHs are reported to holds much amounts of natural gas (up to 182 standard volumes of gas per volume of hydrate); they are easy to store and safe to carry at about minus 20 degree Celsius under atmospheric pressure because of the self-preservation phenomenon of gas hydrates. The transporting method by gas-ice-hydrate ship carriers has been introduced and developed by a variety of industry and research institutions. Our team has been conducted to develop NGH total systems, including a breakthrough NGH carrier for sea transportation, since 2011. The NGH pellet carrier does not require a separate cooling system for cargo, and the initial temperature is maintained through insulation of the cargo tanks throughout the transport to the final destination. The heat conducted from the exterior and passing through the insulation material of the hull should be cut off as much as possible, but heat inflow inside the cargo tank from an external source is inevitable during transport. In this study, the heat transfer in a cargo tank of a 115K NGH carrier was analyzed through simulation with a commercial CFD code to estimate the boil-off gas/boil-off rate on the developed carrier and understand major hazards that could significantly impact the safety of the vessel.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.3
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• pp.1311-1317
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• 2014

This is a descriptive study that attempts to provide basic information for easing job strain and enhancing the efficiency of cosmetology industry workers by examining the effects that the emotional labor and stress-coping of cosmetology workers have on their job strain. As a result of a multiple regression analysis of the factors affecting the subjects job strain, their surface acting and problem-focused coping, unconcern coping, social support were seen as factors that accounted for 30% of their job strain. Of the emotional labor of the subjects, the external behaviors displayed positive correlations with job strain; and they showed negative correlations with problem-focused coping and social support. Concerning emotional labor, sincere behavior was found to have positive correlations with problem-focused coping, hoping, social support, positive coping and strain relieving. Based on the results of this study, it is deemed that, along with interventions for emotional labor, education and intervention programs for a healthy and positive stress coping are needed in regards to interventions for cosmetology professionals.

• Ocean and Polar Research
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• v.40 no.3
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• pp.169-176
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• 2018

Recently, the pop-up satellite archival tag (PSAT) is being used in studies as a method of using satellites for monitoring organisms. Because PSATs are attached directly on the organism being monitored, it is used mostly on larger species since the health of the organism is an important concern. For this reason, PSAT-based surveys are lacking in Korea with no studies on the physiological responses of organisms with PSAT attached. Accordingly, as a basic biomonitoring study using PSAT, the present study investigated the physiological changes in fish in response to the attachment of PSAT. The present study used red seabream (Pagrus major) and Korean rockfish (Sebastes schlegelii) as the experimental fish. The PSAT was attached to the muscle below the experimental fish's dorsal fin using a mono filament (n = 3). To investigate the changes in physiological responses according to PSAT attachment, blood samples were collected from all experimental fish, including the control (n = 3), at 1, 7, 14 and 21 days after the attachment. Upon blood sample collection, whole blood was used to measure hematocrit and hemoglobin levels. After separating the plasma, the separated plasma was used to measure the GOT, GPT, glucose, total protein, and cholesterol levels. Meanwhile, the plasma cortisol, superoxide dismutase, and catalase levels were measured using the ELISA method. The results showed that attaching the tag did not have any impact on the immunity and stress response of the experimental fish. The findings in this study also demonstrated the possibility of using PSAT for studying relatively smaller species living in the coastal waters of Korea.

• The Journal of Industrial Distribution & Business
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• v.9 no.4
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• pp.53-62
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• 2018

Purpose - In the development of new products, suppliers involvement and developing products jointly can be said to be strategic activities that utilize the lack of knowledge from external organizations. In this new product development, supplier involvement has been proven to have a positive impact on new product development performance for a long time by previous research. However, sufficient academic research has not been conducted on the influence of supplier involvement in various product strategies or sales strategies that buyers make in order to secure a competitive advantage in the market. This study argues that product strategy and sales strategy used by buyers in the development of new products will control the effect of supplier involvement on new product development performance in order to compensate the lack of these academic aspects. Research design, data, and methodology - Specifically, we selected the modularization strategy of the product as the product strategy, which is considered as an important strategy in the new product development through the preceding research, and the mass customer satisfaction strategy was chosen as the sales strategy. In order to achieve these research objectives, regression analysis was conducted using data from manufacturing productivity panel collected jointly by the Ministry of Industry, Trade and Industry and the Korea Productivity Center. Results - As a result, supplier involvement and new product development performances (development cost efficiency, customer satisfaction) were positively related. The product modularity strategy proved to have an interactive effect on the relationship between supplier involvement and new product development performances (development cost efficiency, customer satisfaction). However, it has not been confirmed that there is a statistically significant interaction effect between supplier involvement and new product development performances. Conclusions - Supplier involvement has positive relationships with NPD performance. In addition, product modularity strategies have interaction effects with supplier involvement and affect new product development performance (development cost efficiency and customer satisfaction). The results of this study are of academic significance in the case of lack of empirical studies on the effect of supplier participation on the effect of buyer 's strategy when a supplier participates and develops new products jointly.

• Journal of the Korean Society for Nondestructive Testing
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• v.35 no.4
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• pp.245-250
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• 2015

To verify the possibility of generating rattling noise from a motor on caliper brake system, a test was conducted using a caliper excited with vibrations similar to that in a vehicle running on actual roads; this test was conducted using a quiet shaker installed in an anechoic room. After several hours of external excitation, the test assembly was loosened, and the frequency of rattling noise generation increased. A microphone was used to record the generated noise. The measured signals were analyzed by conventional spectrum analysis. Since the noise is generated as an impact response, the advantages of employing Prony analysis was discussed, and the results were compared to those obtained using conventional fast Fourier transforms. The accuracy of Prony analysis was through endurance tests on different brake systems.

• Journal of Korea Society of Industrial Information Systems
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• v.23 no.4
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• pp.107-121
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• 2018

This study investigates the effects of the Kano model on the product quality and quality satisfaction on the FDM low cost 3D printer, which is used by consumer and makers. 3D printer product quality is analyzed in terms of functionality, usability, durability, reliability and safety based on the inherent quality of the product itself. This study were tested using Kano analysis to calculate the product detail characteristics and Timko coefficient to calculate the degree of satisfactory effects of the 3D printer. As a result, this study becomes product size, the output speed, durability against external impact as attractive quality and the safety part is regarded as One-dimensional quality. With the exception of surface resolution, the Timko customer satisfaction index was the same as the Kano model.