• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1030-1035
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• 2002

Despite health benefits derived from fish oil, polyunsaturated fatty acids (PUFAs) contained in fish oil are susceptible to lipid oxidation. To determine the optimum condition for maintaining good quality cooked fish during storage, mackerels were broiled with salt or soysauce condiments, and the lipid oxidation during 12 days of storage at refrigerated condition was measured. Peroxide value of broiled mackerel group with salt significantly increased after immediate cooking and maintained higher value throughout the storage period compare to the soysauce-added group, but showed similar value to the control group. Conjugated diene content in the soysauce-group was lower than the control and salt-added groups. Malondialdehyde content of broiled mackerel increased twofold and showed similar values in soysauce-added and the control groups during storage, whereas increased in the salt-added group significantly. Fatty acid compositions of the three mackerel groups changed after cooking, whereas that of the control group was almost stable during storage. In comparison with raw mackerel, the ratio of PUFA and saturated fatty acids decreased significantly, and the content of n-3 family fatty acid decreased from 25.53 to 20.63% in salted broiled mackerel. Soysauce group showed no reduction of PUFA with increasing storage time and showed the highest ratio of n-3/n-6 among the three groups at 10 days storage. Results reveal soysauce condiment protects against lipid peroxidation of broiled mackerel. Maillard reaction products (MRPs) found in soysauce might be responsible for the inhibitory effect and is a good condiment for extending storage life of cooked fish containing high amount of PUFA.

• KEPCO Journal on Electric Power and Energy
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• v.5 no.3
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• pp.209-213
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• 2019

Recently, demand for high energy density and long cycling stability of energy storage system has increased for application using with frequency regulation (F/R) in power grid. Supercapacitor have long lifetime and high charge and discharge rate, it is very adaptable to apply a frequency regulation in power grid. Supercapacitor can complement batteries to reduce the size and installation of batteries. Because their utilization in a system can potentially eliminate the need for short-term frequent replacement as required by batteries, hence, saving the resources invested in the upkeep of the whole system or extension of lifecycle of batteries in the long run of power grid. However, low energy density in supercapacitor is critical weakness to utilization for huge energy storage system of power grid. So, it is still far from being able to replace batteries and struggle in meeting the demand for a high energy density. But, today, LIC (Lithium Ion Capacitor) considered as an attractive structure to improve energy density much more than EDLC (Electric double layer capacitor) because LIC has high voltage range up to 3.8 V. But, many aspects of the electrochemical performance of LIC still need to be examined closely in order to apply for commercial use. In this study, in order to improve the capacitance of LIC related with energy density, we designed new method of pre-doping in anode electrode. The electrode in cathode were fabricated in dry room which has a relative humidity under 0.1% and constant electrode thickness over $100{\mu}m$ was manufactured for stable mechanical strength and anode doping. To minimize of contact resistance, fabricated electrode was conducted hot compression process from room temperature to $65^{\circ}C$. We designed various pre-doping method for LIC structure and analyzing the doping mechanism issues. Finally, we suggest new pre-doping method to improve the capacitance and electrochemical stability for LIC.

• Korean Journal of Remote Sensing
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• v.37 no.5_1
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• pp.989-998
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• 2021

In the utilization of optical satellite imagery, which is greatly affected by clouds, periodic composite technique is a useful method to minimize the influence of clouds. Recently, a technique for selecting the optimal pixel that is least affected by the cloud and shadow during a certain period by directly inputting cloud and cloud shadow information during period compositing has been proposed. Accurate extraction of clouds and cloud shadowsis essential in order to derive optimal composite results. Also, in the case of an surface targets where spectral information is important, such as crops, the loss of spectral information should be minimized during cloud-free compositing. In thisstudy, clouds using two spectral indicators (Haze Optimized Tranformation and MeanVis) were used to derive a detection technique with low loss ofspectral information while maintaining high detection accuracy of clouds and cloud shadowsfor cabbage fieldsin the highlands of Gangwon-do. These detection results were compared and analyzed with cloud and cloud shadow information provided by Sentinel-2A/B. As a result of analyzing data from 2019 to 2021, cloud information from Sentinel-2A/B satellites showed detection accuracy with an F1 value of 0.91, but bright artifacts were falsely detected as clouds. On the other hand, the cloud detection result obtained by applying the threshold (=0.05) to the HOT showed relatively low detection accuracy (F1=0.72), but the loss ofspectral information was minimized due to the small number of false positives. In the case of cloud shadows, only minimal shadows were detected in the Sentinel-2A/B additional layer, but when a threshold (= 0.015) was applied to MeanVis, cloud shadowsthat could be distinguished from the topographically generated shadows could be detected. By inputting spectral indicators-based cloud and shadow information,stable monthly cloud-free composited vegetation index results were obtained, and in the future, high-accuracy cloud information of Sentinel-2A/B will be input to periodic cloud-free composite for comparison.

• Journal of the Korean Orthopaedic Association
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• v.53 no.6
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• pp.505-512
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• 2018

Purpose: Many reconstruction methods have been attempted after an en-bloc resection of the proximal humerus. In particular, the introduction of reverse shoulder arthroplasty (RSA) has made a breakthrough in the functional recovery of the shoulder. Nevertheless, RSA has limitations when the humeral bone stock loss is significant. In addition, it is unclear if RSA is effective in patients showing failure with non-operative treatment of a proximal humeral tumor. Materials and Methods: A reconstruction was performed using an overlapping allograft-RSA composite for 11 patients with a failed proximal humeral construct. Delayed RSA was performed on 6 patients with failed non-operative treatment. The pre- and postoperative Musculoskeletal Tumor Society (MSTS) score and the complications were addressed. Results: Overlapping allograft-RSA composite afforded a stable construct in 11 failed proximal humeral reconstructions and the patient's chief complaints were resolved. The mean time to the union of overlapped allograft-host junction was 5.5 months. Average preoperative MSTS score of 20.3 point increased to 25.7 point, postoperatively. Four of the six patients who had RSA within 4 years from the index operation showed arm elevation of more than $90^{\circ}$ whereas the remaining 5 patients showed some disability. The complications include one case each of dislocation and aseptic infection, which were resolved by changing the polyethylene liner and scar revision, respectively. None of the 6 patients who underwent delayed RSA after the failure of non-operative treatment showed arm elevation more than $90^{\circ}$. Conclusion: An overlapping allograft-RSA composite is a simple and reliable reconstructive modality in patients with massive bone loss. In patients with metastatic cancer necessitating a surgical resection at presentation, early conversion to RSA is recommended to secure functional recovery.

• Journal of Conservation Science
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• v.34 no.6
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• pp.595-604
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• 2018

In this study, in a bid to develop natural bioadhesives for paper craft, the hanji industry, and preserving cultural assets, complex polysaccharides were extracted from brown and red algae and used as an ingredient in adhesives. Brown algae include sea trumpet, kelp, sea oak, and sea mustard, whereas red algae include Pachymeniopsis elliptica agar-agar weed, Gloiopeltis tenax, and hunori. The polysaccharides were extracted after transforming them from non-aqueous Ca complexes contained in each of the brown and red algae into water-soluble polysaccharides containing alkali metals with a solubility level of 1. and extracted Subsequently, only the polysaccharides were extracted using alcohol precipitation. The adhesion tensile strengths of kelp, a brown algae, and Pachymeniopsis elliptica, a red algae, were 21.58 and 32.99 kgf, respectively. They thus demonstrated better adhesion than that of solid glue products such as water plants (18.45 kgf) and glue sticks (20.45 kgf). The extraction yield of these polysaccharides is supposed to be determined according to their extracted environments; however, no difference in adhesion strength was seen. Further, it was found that the shapes of polysaccharides were determined by their growing environment instead of extraction environment. Use of multi-step alcohol precipitation method during extraction enabled the removal of the constituents except protein and other polysaccharides, thereby demonstrating a stable outcome without cultivation of mold. Furthermore, there was no occurrence of mold even after production of the adhesives by the simple solution method, which demonstrates the adhesive's potential as an environment-friendly adhesive material.

• The Korean Journal of Archival Studies
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• no.50
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• pp.273-309
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• 2016

Unlike other government agencies, the city of Seoul experienced a three-year gap between the establishment of a function classification system and the introduction of a business management system. As a result, the city has been unable to manage the current status of the function classification system, and this impeded the establishment of standards for records management. In September 2012, the Seoul Metropolitan Government integrated the department in charge of the standard sheet for record management with the department of function classification system into a new department: "Information Disclosure Policy Division." This new department is mainly responsible for record management and information disclosure, and taking this as an opportunity, the city government has pushed ahead with the maintenance project on BRM and Standards for Record Management (hereby "BRM maintenance project") over the past two years, from 2013 to 2014. The study was thus conducted to introduce the case for the improvement of standards for record management through the BRM maintenance project by mainly exploring the case of Seoul. During the BRM maintenance project, Seoul established a unique methodology to minimize the gap between the operation of a business management system and the burden of the person in charge of the BRM maintenance project. Furthermore, after the introduction of the business management system, the city government developed its own processes and applied the maintenance result to the system in close cooperation with the related departments, despite the lack of precedence on the maintenance of the classification system. In addition, training for the BRM managers of the department has taken place twice -before and after the maintenance-for the successful performance of the BRM maintenance project and the stable operation of the project in the future. During the period of maintenance, newsletters were distributed to all employees in an effort to induce their active participation and increase the importance of records management. To keep the performance of the maintenance project and to systematically manage BRM in the future, the city government has mapped out several plans for improvement: to apply the "BRM classification system of each purpose" to the service of the "Seoul Open Data Plaza"; to reinforce the function for task management in the business management system; and to develop the function of a records management system for the unit tasks. As such, the researchers hope that this study would serve as a helpful reference so that the organizations-which had planned to introduce BRM or to perform the maintenance project on classification system-experience fewer trials and errors.

• Journal of the Korean Applied Science and Technology
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• v.36 no.1
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• pp.324-332
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• 2019

Most countries including Korea and Indonesia have strong policy for implementing biofuels like biodiesel. Shortage of the oil feedstock is the main barrier for increasing the supply of biodiesel fuel. In this study, in order to improve the stability of feedstock supply and lower the biodiesel production cost, the feasibility of biodiesel production using two types of Indonesian tropical crop oils, pressed at different harvesting times, were investigated. R. Trisperma oils, a high productive non-edible feedstocks, were investigated to produce biodiesel by esterification and transesterification because of it's high impurity and free fatty acid contents. the kindly provided oils from Indonesia were required to perform the filtering and water removal process to increase the efficiency of the esterificaton and transesterification reactions. The esterification used heterogeneous acid catalyst, Amberlyst-15. Before the reaction, the acid value of two types oil were 41, 17 mg KOH/g respectively. After the pre-esterification reaction, the acid value of oils were 3.7, 1.8 mg KOH/g respectively, the conversions were about 90%. Free fatty acid content was reduced to below 2%. Afterwards, the transesterification was performed using KOH as the base catalyst for transesterification. The prepared biodiesel showed about 93% of FAME content, and the total glycerol content was 0.43%. It did not meet the quality specification(FAME 96.5% and Total glycerol 0.24%) since the tested oils were identified to have a uncommon fatty acid, generally not found in vegetable oils, ${\alpha}$-eleostearic acid with much contents of 10.7~33.4%. So, it is required to perform the further research on reaction optimization and product purification to meet the fuel quality standards. So if the biodiesel production technology using un-utilized non-edible feedstock oils is successfully developed, stable supply of the feedstock for biodiesel production may be possible in the future.

• Journal of Korean Society of Forest Science
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• v.100 no.2
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• pp.202-211
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• 2011

The geometric characteristics of step-pool structures and how they are influenced by channel characteristics were investigated in a steep mountain stream in the Experimental Forests of Kangwon National University in Chuncheon, Gangwon-do. Average values of steps for the study reaches were as follows: step spacing, 4.69 m; step height, 0.47 m; step drop, 0.71 m; step-forming particle sizes, 0.68 m; number, 21steps/ 100 m; the ratio of step spacing to channel width, 0.5; and step steepness, 0.13. Relationships between spacing and height of steps and channel gradient showed a negative- and positive correlation, respectively, whereas all geometric variables of steps manifested poor correlation with channel width. Therefore, step steepness, expressed as the ratio of step height to step spacing, increased as channel gradient increased. The ratio of step steepness to channel gradient representing the criterion of maximum flow resistance was 1.2, indicating the channel bed's stable condition. In particular, the relationship between the ratio of step drop to step height and channel gradient showed a significant negative correlation, suggesting the influence of step-pool geometry in trapping sediment and providing an aquatic habitat. Positive correlations also exist between spacing and drop of steps and step particles. Our findings suggest that the dynamics of step-pool structures may strongly control physical and ecological environments in steep mountain streams, so understanding them is essential for stream management.

• (The) Research of the performance art and culture
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• no.34
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• pp.315-353
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• 2017

This study examined the music policies of the three kings, Seongjong, Jungjong, and Injo, who were in power for about 200 years from the late 15th century to the early 17th century. These three kings deserve attention in musical history for different reasons. Sungjong published "Gugjooryeui"(1474), "Gyeong-gugdaejeon"(1476), and "Aghaggwebeom"(1493), the typical etiquette books, law books, and musical books that take the most important position in the history of Joseon, so his direction of music policy deserves attention. Jungjong was the king who rose to the throne after there was a revolt against Yeonsangun's tyranny. Injo ascended to the throne by starting a military coup d'etat himself. One may wonder how the aspect of music policies developed by a king, who was crowned by a revolt, is different from other cases. As each of these three kings had different background of enthronement and the contents of music policies in the royal family also developed with different emphasis, this study examined each aspect separately. Sungjong emphasized the importance of music and regarded it important to cultivate officials who know music. To this end, he gave a special order to Yejo(the office of protocol) and this study tried to clarify the contents first. In addition, this study examined the process, contents, and meaning of various modification works related to the revision of the lyrics used in the ceremonies. Jungjong supplemented the institutional aspects of music. This is the result of expressing the will to correct the anomalous and reckless music policies of the period of Yeonsangun. In addition, many words in the lyrics had been about Buddhist doctrines and love songs between male and female, so there were efforts to reform these. As for the period of Injo, this study examined the music policies that were made in the process of resolving the crisis after the war. It was a time when court musicians were scattered after two times of war and it was not possible to hold the national ritual properly, so music policies in this period were different from the ones in stable era. This study covered discussions on the measures to collect lost instruments and scattered musicians. It also looked at how the restoration effort was made in the situation that the music used in ancestral rites was abolished.

• Journal of the Korean Applied Science and Technology
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• v.37 no.6
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• pp.1517-1527
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• 2020

This study is about the UV protection effect and water resistance of a multiple emulsion (W/O/W) sunblock cream applied with emotional engineering and reports an actual industrial case. Multiple emulsion system of sunblock cream has the characteristics of changing to a W/O type that is soft and moist when applied, and has excellent water resistance after absorption. Multiple emulsion cream is a highly functional sunblock cream that has both moisture and water resistance. It is a stable milky white cream with a viscosity of 36,000 cps. The organic sunscreen used for the sunscreen was ethylhexylmethoxycinnamate and bisethylhexyloxyphenolmethoxyphenyltriazine. Hexagonal zinc oxide and titanium dioxide that block both UVB and UVA were used. As a result of measuring the UV protection effect by the in-vitro method, the UV protection effect (SPF) is 78.9 for multiple emulsion cream, 76.7 for W/O cream, and 71.3 for O/W cream. It was found that the blocking effect was different. This obtained the highest effect value in the multiple emulsion. As a clinical (in-vivo) result of the UV protection effect, the SPF value representing the UV protection effect of the sunblock cream developed with a multiple emulsion system was 85.7, and the PA-value that blocks the UVA area was 26.5, and ++++. It was found that it has a corresponding high blocking effect. As a result of the water resistance test, the W/O/W formulation had a high waterproofing resistance of 93.8% even after 4 hours, W/O had 75.4%, and O/W had a low water resistance of 25.3%. In the results of the HUT test, it was found in the order of multiple emulsion sun block cream > hydrophilic cream > lipophilic cream. Based on the research results of this multiple emulsion, it is expected to be highly active as a sunblock cream dedicated to outdoor activities by improving the feeling of use, UV protection index, and water resistance. Therefore, in this study, a multiple emulsion system of sunblock cream is developed and has a characteristic that changes to a W/O type that has a soft and moist feeling when applied, and has excellent water resistance after absorption.