• Applied Chemistry for Engineering
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• v.34 no.2
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• pp.161-169
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• 2023

In this study, we prepared naproxen (NP) imprinted biodegradable polymer based multi-layer biomaterials using allbanggae starch (ABS), polyvinyl alcohol (PVA), and alginic acid (SA), and investigated their physicochemical properties and the controlled drug release effects. In addition, the prepared multi-layer biomaterials were characterized by FE-SEM and FT-IR. In order to confirm the controlled drug release effect for the transdermal drug delivery system (TDDS), the NP release properties of NP imprinted multi-layer biomaterials were investigated using various pH buffer solutions and artificial skin at 36.5 ℃. The results of NP release in various pH buffer solutions indicated that the NP release at high pH was about 1.3 times faster than that at low pH. In addition, NP release in multi-layer biomaterials was about 4.0 times slower than that in single-layer biomaterials. It was confirmed that the NP release rate in triple-layer biomaterials was 4.0 times slower than that in single-layer biomaterials while using artificial skin. Also, it could be found that NP in double-layer biomaterials and triple-layer biomaterials was released sustainably for 12 h. The NP release mechanism in pH buffer solutions followed the Fickian diffusion mechanism, but followed the non-Fickian diffusion mechanism with artificial skin.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.35 no.1
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• pp.1-12
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• 2023

Along with the growing interest in renewable energy development, Korea's west coast is one of the favorable regions for tidal power. Tidal power using tidal barrages that work like hydroelectric dams is a representative method of tidal power through long-term operation, but the promotion of tidal power projects is being delayed or stopped due to impacts on ecological changes, reproduction, water column processes and hydrology. In order to reduce the high construction cost and environmental cost problems caused by tidal power using tidal barrages, in this study, field experiments were conducted to develop and verify the performance of tidal power generation devices applicable to sea areas where dykes are already installed. As a result of conducting five cases of experiments using two water tanks, pipe lines, open channels, and water turbine and generator, the possibility of developing a power generation system capable of generating more than 10 kW output and more than 60% efficiency were confirmed. The results of this study can be used for small-scale tidal power by utilizing the existing dykes of the west coast.

• Journal of the Society of Disaster Information
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• v.19 no.2
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• pp.411-420
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• 2023

Purpose: In order to compensate for the limitations of the risk assessment of hydrogen charging stations, it is proposed to apply business disaster reduction activities as a way to strengthen safety and business continuity for accidents that may occur during operation. Method: We explored the application of business disaster reduction activities that can reduce, eliminate, transfer, and accept risks by classifying risks according to the passage of time in the installation and operation of hydrogen charging stations, identifying key tasks, deriving risk scenarios. Result: Existing research results are appropriately applied to the risk assessment conducted in the stage before the installation of hydrogen charging stations. However, there is a limit to the risks that can occur at the operational stage, so applying business disaster reduction activities with several example scenarios has resulted in that it can be applied as a way to strengthen safety and business continuity. Conclusion: All of the currently implemented risk assessments for hydrogen charging stations are being used appropriately. However, it proposes business disaster reduction activities that apply various risk scenarios as an evaluation and response to possible risks at the operational stage.

• Korea Trade Review
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• v.41 no.2
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• pp.231-250
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• 2016

The study attempts to consider L/G(Letter of Guarantee) in a different angle, which is internationally used as a way of commercial customs and practices in a case when the consignee wants to receive the goods without the original Bill of Lading, Thus, this study focuses more on verifying the usage of L/G in Mixed Payment System and the range of guarantee responsibility by an issuing bank through case analysis. This case uses a mixed payment method of L/C(Letter of Credit) and T/T(Telegraphic Transfer) in the transaction of goods. The issuing bank of L/C issues L/G with the amount of L/C which is the same as the amount as C/I(Commercial Invoice). However the carrier deliver all goods laden under both L/C and T/T payment with the production of L/G. In this case, because the buyer is unable to pay, the seller makes a claim for damages to the carrier that the carrier delivers the goods to the buyer against L/G. Finally, the judge gives a decision that the issuing bank of L/G should pay the whole amount of the goods. In this case, the main issue of the dispute is the range of guarantee responsibility by the issuing bank of L/G. As a result of the case analysis, the study suggests two counter strategies for smooth utilization in international trade environment. First, in the case of mixed payment system, a seller should issue a commercial invoice separately based on the amount of each settlement plan in order to clarify the liability of guarantee. Second, banks should establish a new form for L/G including a sentence for verifying liabilities of the bank's side in the current form of L/G.

• Journal of the Society of Naval Architects of Korea
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• v.60 no.3
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• pp.186-192
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• 2023

According to the regulation on the pollution of the marine environment, SOx emission from ships has to be reduced. A SOx scrubbing system installed in a funnel of a ship is considered in order to reduce SOx emission. A scrubbing layer with a porous material is present in the funnel to increase the contact area between exhaust gas and water. In this study, experiments on the pressure drop characteristics in the scrubbing layer are conducted to investigate the effect of the scrubber on the engine load. The pressure drop according to flow rate of air instead of exhaust gas was measured for fillers such as sphere, pall ring and saddle in the scrubbing layer. First of all, porosity is experimentally measured for the three types of filler and it is confirmed that the porosity of the saddle-type filler was the largest. The pressure drop according to the change in air flow rate was measured for the three types of fillers in the scrubbing layer. As a result, the pressure drop was the smallest in the scrubbing layer with the saddle-type filler which has the largest porosity. In addition, the effect of spraying water flowing counter flow against air flow is experimentally examined. It is known that the pressure drop is increased because the air flow space is reduced when water is sprayed. In the case of the saddle, the pressure drop is about 1.5 to 2 times greater than that when only air flows at the optimum exhaust gas-water injection ratio.

• Korean Journal of Social Welfare Studies
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• v.42 no.2
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• pp.381-417
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• 2011

The primary goal of this study is to examine the factors that affect how satisfied sexual minorities are with their lives. This study focuses on how sexual minorities perceive social stigma, the social influences involved in its perception, and the effects this perception has. Using stress-coping theory, this study looks at how social stigma, as a perceived stress, affects social support and self-esteem, how the stigma influences the degree to which individuals "come out" in an effort to cope, and the resultant effects of this coping mechanism on life satisfaction. The data used if from a sample of 478 individuals who self identify as gay, lesbian or bisexual. It was collected through an online survey. Using SEM, the quality was evaluated by analyzing the measurement model, and the relationship of the variables included in the theoretical model was verified by analyzing the structural model. The results of this study show that social stigma directly affects the life satisfaction of Korean sexual minorities. It significantly influences the social support they receive(from family and sexual minority peers), and their self-esteem. The degree to which the individual "comes out" is shown to affect life satisfaction as well. In contrast, the mediating effect of heterosexual support is shown to be insignificant. Based on the analyses, practical strategies regarding social stigma, social support, self-esteem, and "coming out" are suggested for sexual minorities. The social stigma should be reduced and society-scaled campaigns promoted in order to improve their level of life satisfaction. In addition, institutional protection should be developed and specialized educational courses on human rights provided which will empower these minorities with self-help mechanisms. Furthermore, issues such as establishing support system and providing a social welfare system for the sexual minority community are discussed.

• Analyses & Alternatives
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• v.1 no.2
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• pp.44-64
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• 2017

From the field survey of the main ethnic minority areas in the south China, it is found that political, economic, cultural and natural environmental changes are the main reasons leading to the change of customary law. The power mechanism of the customary law change include the three aspects, such as the promotion of country elite, the dominance of grassroots government, and the daily demands of the villagers, which promote the change of customary law alone or together. Through the application of customary law, the country elites can adjust and refine the rules of customary law in order to make out the new customary law and promote its development. In the current pattern of rural governance, grassroots self-government is actually the "official supervision of people's autonomy". The executive power of the grassroots government often intervene the practice of customary law and other informal rules. This is another mechanism of customary law change. Customary law arises from the practice of the daily life of the villagers. If the villagers think that the norms of customary law cannot meet the actual needs of daily life practice, the customary law will be promoted in the form of collective consultation. This is the most important dynamic practice mechanism of customary law change. Transformation and abandonment are the two ways to change customary law. No matter what kind of change does not lead to the demise of the customary law system, the demise of the customary law is only an outdated result, which is made by the universality, nature and objectivity of customary law. The procedure of customary law change is the process of continuation and rebirth about customary law. The result of the change is to produce the new customary law of keeping pace with the times, and the customary law will be presented with new content and form after the change. The continuation of customary law means the inheritance of traditional customary law, but it is based on the transformation of traditional customary law. The rebirth of customary law means that the traditional customary law is completely discarded. But it will produce new customary law rules and be based on the needs of social life practice. Customary law occupies a pivotal position in the normative system and the national law cannot be replaced. The purpose of customary law change will let the customary rules better adapt to the development of modern society, adjust the social relations more reasonably and better meet people's needs of production and life, which is decided by the character of customary law.

• Journal of the Korean Society of Radiology
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• v.18 no.3
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• pp.239-248
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• 2024

Radiation therapy uses high energy, which can have side effects on the human body. Therefore, it is important to ensure that the appropriate dose is set for irradiation and to have confidence in the radiation produced by the generator. The EPR/Alanine dosimetry system is characterized by water equivalence, dose response linearity, and low fading, which makes it useful for quality control of radiation therapy equipment. In this study, we compared the signal and dose response curves of EPR/Alanine dosimetry by mass of alanine using 6 MV energy of a LINAC. An alanine dosimeter and EPR spectrometer from Burker, and a LINAC from Elekta, were used. A dose response curve and a 1st order regression equation were constructed from the irradiated dose and the EPR signal from the alanine dosimeter. We compared the signal magnitude and dose response curve with mass and checked the confidence through the measurement uncertainty of the dose response curve. As a result, it was found that the magnitude of the EPR signal increased by about 1.3 times at 64.5 mg, and the sensitivity of the dose response curve increased as the mass increased. The measurement uncertainty was evaluated to be between 5.84 % and 8.93 %. Through this study, it is expected that the EPR/alanine dosimetry system can be applied to the quality assurance and quality control of a LINAC.

• Journal of Christian Education in Korea
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• v.77
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• pp.225-249
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• 2024

Research Purpose : Based on artificial intelligence, this study considers learners' characteristics, learning content, and individual learning, and analyzes the collected learning data to develop a model that supports customized learning for individual learners. Research content and method : In order to achieve the research purpose, the literature was analyzed to investigate the structure of customized learning support, learning data analysis, and learning activities, and based on the investigated data, the area and detailed components of the customized learning support model were derived. did. A draft model was constructed through literature analysis, and the first expert Delphi survey was conducted on the draft model with five experts. The model was revised by reflecting the results of the first Delphi, and the validity of the revised model was verified through the second expert Delphi. The model was elaborated through expert Delphi, and the final model was constructed through this. Conclusion and Recommendation : Through research, customized learning support area, class management system area, and learning analysis data area were formed, and detailed elements were derived for each area. The results of this study provide basic data that can be used as a reference for constructing a customized learning support system based on artificial intelligence, taking into account the university's class environment.

• Journal of Korea Port Economic Association
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• v.39 no.4
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• pp.191-203
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• 2023

This paper analyzed the overall status of the domestic freight transportation business, established SWOT analysis and strategy through existing literature research and designed an AHP model to derive priorities for each strategy. The SWOT analysis analyzed the management model of the consignment borrowers belonging to a transportation company that did not handle the supplies with the lowest satisfaction with the consignment system. The AHP model was designed by establishing a SWOT strategy through SWOT analysis. As a result of the analysis of the upper class, priorities were derived in the order of WO strategy, SO strategy, ST strategy, and WT strategy. As a result of comprehensive priorities for the development strategy of the domestic freight transportation business, WO strategy's "Improvement of cooperative relations between transportation companies and consignment owners through fair consignment contracts" was first, SO strategy's "Public promotion of the necessity of consignment systems based on high economic feasibility and reliability" was second, and ST strategy's "Proposal of policies to strengthen financial performance through the introduction of freight transport platforms" was fourth, followed by WT strategy's "Improvement of satisfaction with transport services through the introduction of freight transport platforms" and SO strategy's "Expansion of safe freight systems" in sixth, respectively.