• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.672-680
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• 2018

The opening angle of the duct cap assembly during the operation of a refrigerator ice dispenser was evaluated by transient structural analysis, and an improved design to maximize the opening angle was obtained. The opening angle of the existing design was found to be 78% of the upper limit. Several design modifications were proposed and analyzed to examine the effects of the design factors on the opening angle. As a result of the design modifications, the opening angle was improved by changing the lever material to a material with a high elastic modulus, moving the position of the support to the motor side, or increasing the lever shaft diameter. Considering the manufacturing cost of the new design, the design modification changing only the lever material was found to be the best because it does not require a change in the structure of the ice dispenser case. In conclusion, the opening angle can be improved by up to 95% of the upper limit value if the lever material is changed to an aluminum alloy. The methods and results presented in this study were found to be of great help in designing the duct cap assembly structure to facilitate the discharge of ice.

• Journal of Nutrition and Health
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• v.13 no.3
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• pp.139-144
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• 1980

A study was conducted to examine the physical and chemical changes of wines fermented from three different varieties by three different methods. The products were evaluated by twenty subjects on color, aroma, and taste. The results were as follows; 1) The moisture contents of those varieties were ranged from 90. 70 to 90.82% The Brix sugar and sugar contents were in order of Muscat Bailey A>Alden>Cambell Early. The titratable acidity was higher in Muscat Bailey A and Alden than in Cambell Early while PH of Cambell Early was higher than those of the two others. 2) The specific gravities of the products were slightly decreased as the fermentation progressed. 3) The yeast-fermentation showed the higher degree of alcoholic contents compared to the natural fermentations. of the natural fermentations, the washed-natural fermentation resulted in the lower alcoholic contents than unwashed one. 4) The PH's were also higher in the yeast-fermentation products than in the natural fermentation groups. The difference, however, was smaller as the fermentation progressed further. 5) The total ester coutents of the yeast fermentation group were slightly higher at the beginning of the fermentation than those of the natural fermentation products and the contents were increased during the fermentation in overall. 6) Twenty panel mentors judged the ripe wine products and the order of preference was Alden>Muscat Baliey A>Cabell Early. They preferred the yeast-fermentation wine to the natural fermentation products.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.2
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• pp.219-226
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• 2020

Nondestructive testing is one of the most commonly used quality inspection methods for evaluating ship structures. However, accurate evaluation is dif icult because various composite materials, such as reinforcements, resin, and fiber-reinforced plastics (FRPs), are used in hulls, and manufacturing quality differences are likely to exist owing to the fabrication environment and the skill level of workers. This possibility is especially true for FRP ships because they are significantly thicker than other structures, such as automobiles and aircraft, and are mainly manufactured using the hand lay-up method. Because the density of a material is a critical condition for ultrasonic inspection, in this study, a hull plate was selected from a vessel manufactured using e-glass fiber, which is widely used in the manufacture of FRP vessels with the weight fraction of the glass content generally considered. The most suitable ultrasonic testing conditions for the glass FRP hull plate were investigated using a pulse-echo ultrasonic gauge. A-scans were performed with three probes (1.00, 2.25, and 5.00 MHz), and the results were compared with those of the hull plate thickness measured using a Vernier caliper. It was found that when the probe frequency was higher, the eco-pulse velocity of the receiver had to be lowered to obtain accurate measurement results, whereas fewer errors occurred at a relatively low probe frequency.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.3
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• pp.315-322
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• 2014

Purpose: The physical and optical characteristics of hydrophilic tinted contact lens containing titanium silicon oxide nanoparticles and the basic hydrogel contact lens material containing 4-iodoaniline were examined. In this study, the utility of titanium silicon oxide nanoparticles as a UV-blocking material for ophthalmologic devices were investigated by measuring the UV transmittance of the produced polymer. Also, titanium silicon oxide nanoparticles only without the addition of 4-iodoaniline in primary contact lens materials by copolymerizing two groups were compared. Methods: For manufacturing hydrogel lens, HEMA, MA, MMA, 4-iodoaniline and a cross-linker EGDMA were copolymerized in the presence of AIBN as an initiator. Also, the titanium silicon oxide nanoparticles was used as additive. After polymerization the physical properties such as water content, refractive index, contact angle and spectral transmittance of produced contact lenses were measured. Results: Measurement of the physical properties of the copolymerized material showed that the water content, refractive index, UV-B transmittance and contact angle were in the range of 35.01~38.60%, 1.4350~1.4418, $34.15{\sim}57.25^{\circ}$ and 1.0~10.0%, respectively. Titanium silicon oxide nanoparticles is not used as an additive in the experimental group, the results of the measurement showed that the water content, refractive index, contan angle and UV-B transmittance of the hydrogel lens polymer was 34.00~36.80%, 1.4378~1.4420, $40.15{\sim}60.16^{\circ}$ and 1.8~25.0%, respectively. Conclusions: Also, the transmittance for UV light was reduced significantly in combinations containing titanium oxide nanoparticles.

• The Journal of Korean Society for Radiation Therapy
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• v.19 no.1
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• pp.7-17
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• 2007

Purpose: As increasing complexity of modern radiotherapy technique, more developing dosimetry is required. Polymer gel dosimeters offer a wide range of potential applications with high resolution and assured quality in the thee-dimensional verification of complex dose distribution such as intensity-modulated radiotherapy (IMRT). The purpose of this study is to find the most sensitive and suitable gel as a dosimeter by varying its composition ratio and its condition such as temperature during manufacturing. Materials and Methods: Each polymer gel with various ratio of composition was irradiated with the same amount of photon beam accordingly. Various polymer gels were analyzed and compared using a dedicated software written in visual C++ which converts TE images to R2 map images. Their sensitivities to the photon beam depending on their composition ratio were investigated. Results: There is no dependence on beam energy nor dose rate, and calibration curve is linear. Conclusion: The polymer gel dosimeter developed by using anti-oxidant in this study proved to be suitable for dosimetry.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.8
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• pp.342-347
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• 2020

Recently, as the collaborative robot has been introduced into the domestic industrial robot market, it is installed mainly in the manufacturing industry. Collaborative robots are subject to the safety regulations of industrial robots by Article 93 of the Safety Inspection of the Industrial Safety and Health Act. The sites where collaborative robots are to be installed must perform risk assessments for robots-humans, work environments, and work methods and reduce the risks according to ISO 10218-2 and ISO 12100. On the other hand, because it is early in the introduction of collaborative robots, new risks for collaborative robots have not been issued, and risk assessments are unfamiliar and difficult to apply in the workplace. The risk assessment of collaborative robots aims to identify and reduce the risk of a high probability of occurrence by focusing on the abnormal behavior of humans, human errors, equipment defects, and interlock functions. In this study, a risk assessment was applied to a domestic automobile parts production plant, and improvement measures were drawn. This risk assessment is expected to be useful for improving the safety of small businesses by continuously discovering risk assessment examples of collaborative robots.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.7
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• pp.92-102
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• 2016

In this study, the systems and standards for temporary equipment and materials established in domestic and foreign countries are examined to provide improvement schemes and to insure their safety. Statistical analyses of the data obtained from the internet and/or field visit surveys of employees working in manufacturing, leasing, and construction companies related to temporary equipment and materials and improvement schemes were conducted to evaluate the implementation of a safety certification system for currently used temporary equipment and materials. This safety certification system has been enforced since 2009, but the number of accidents at construction sites, which are reported by the 'serious accident cases and measures in construction sites' group of the Korea Occupational Safety & Health Agency (KOSHA), has increased. The respondents' answers regarding the suitability of the items, which are required for the safety certification of the equipment and materials, were 'yes (36%)', 'no (30%)', and 'unknown (35%)'. Less than half of the answers regarding the current system were positive and most of the respondents answered that the current system does not reflect the evolution of the construction environment. A system is needed to approve items certified in foreign countries and newly developed materials and items, in addition to the (automatic) registration for the reuse of temporary equipment and materials, and improvements are needed in their safety. In this study, after examining the size and practicability of the items requiring approval from the current system, the certification methods are reevaluated and improvement schemes are provided for the system.

• Journal of Korean Medical classics
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• v.23 no.4
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• pp.63-102
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• 2010

Purpose : To propose various types of clinical research which is feasible for botanical new drug (IND) development processes, and suggest essential steps to development of study protocol for IND. Methods : Literature-based discussions and one research group's experience is given regarding domestic act, regulation, and system. Results : In order to get an approval of IND for botanical drug in Korea there are several types of clinical research to conduct. In quality control steps for standardized medicinal herbs, case reports or case series can be conducted, and for good manufacturing practice(GMP) steps, we can conduct case reports, case series, and retrospective cohort studies. In addition, as long as we gathered good laboratory practice(GLP) data we can conduct up to quasi-experimental studies and clinical trials including investigator initiated trials. In order to conduct these studies development of study protocol is essential. First, we obtain historical evidence including target disease and indication, efficacy, safety, and endpoints by reviewing medical classics. Second, we obtain clinically and statistically important data by conducting non-clinical studies, observation studies, and quasi-experimental studies. Third, we generate research hypotheses and purposes and explore methodologies, endpoints, clinical practice guidelines, cost-effectiveness, and commercial potential. Finally, we develop study protocol with aid of biostatistician or expert in contract research organization. Discussions and conclusions : This study have obvious limitations in that most thoughts, suggestions, and proposes are from one research group's experience. Therefore, we hope to see various types of research in this topic and process from other research group as well.

• Korean Journal of Oriental Medicine
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• v.18 no.3
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• pp.87-93
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• 2012

Objectives : The present study is to verify whether the deformation of ear acupuncture needle tips that are currently on the market is caused during the process of initial packaging. Methods : Ear acupuncture needles distributed from three different companies were collected to measure the size of the groove on the transparent plate which is used in for the intial packaging. Then the tolerance range for off-centered tips, which represent the range of the groove size that is safe from damaging the needle tip, was determined based on the vertical length measured from tip to handle. 200 ear acupuncture needles were dipped in alcohol and scanned to confirm the position of the needles. Stereo-microscope was used to observe the needle tips that were located outside the tolerance range. Results : The increased number of ear acupuncture needle tips placed outside the tolerance range were seen from in the order of C company, A company and B company. The increased deformation of the needle tips caused by initial packaging was observed in the order of A company, C company and B company. Conclusion : Only the ear acupuncture needles from B company showed the strong correlation between needle tip deformation and initial packaging. It has been observed that the deformation of the ear acupuncture needles is mainly due to manufacturing process, not the packaging process.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.256-262
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• 2011

Currently among the several methods to estimate an environmental impact of products, Life Cycle Assessment (LCA) technique is mostly used. The Ministry of Environment has been performed the carbon footprint labelling to give the carbon record of product by using this method. But the calculation of carbon footprint in primary agricultural product which is raw material of the processed food cannot be made because there is lack of methodology and LCI DB at agriculture sector. Therefore, LCA carried out to estimate carbon footprint, and established LCI DB for complex fertilizers (21-17-17 1 kg, 17-21-17 1 kg, 15-15-15 1 kg, Unspecified 1 kg) in the production system. The result of LCI DB analysis focussed on the GHG, and it was observed that the values of carbon footprint were $2.42E+00kg\;CO_2-eq.kg^{-1}$ for 21-17-17, $2.10E+00kg\;CO_2-eq.kg^{-1}$ for 17-21-17, $2.23E+00kg\;CO_2-eq.kg^{-1}$ for 15-15-15 and $3.56E+00kg\;CO_2-eq.kg^{-1}$ for Unspecified. For the analysis of LCIA (Life Cycle Impact Assessment) on complex fertilizers in the production system, the carbon footprint from pre-manufacturing phase is contributed to 98.96%, 98.81%, 98.88% and 99.30% on each complex fertilizer with 21-17-17, 17-21-17, 15-15-15, and Unspecified, respectively. These results will be used in basic data for estimation of agricultural greenhouse gas emissions.