• Journal of Electrochemical Science and Technology
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• v.15 no.1
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• pp.96-110
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• 2024

Polymer electrolyte membrane fuel cells (PEMFCs) are green energy conversion devices, for which commercial markets have been established, owing to their application in fuel cell vehicles (FCVs). Development of cathode electrocatalysts, replacing commercial Pt/C, plays a crucial role in factors such as cost reduction, high performance, and durability in FCVs. PtNi octahedral catalysts are promising for oxygen reduction reactions owing to their significantly higher mass activity (10-15 times) than that of Pt/C; however, their application in membrane electrode assemblies (MEAs) is challenged by their low stability. To overcome this durability issue, various approaches, such as third-metal doping, composition control, halide treatment, formation of a Pt layer, annealing treatment, and size control, have been explored and have shown promising improvements in stability in rotating disk electrode (RDE) testing. In this review, we aimed to compare the features of each strategy in terms of enhancing stability by introducing a stability improvement factor for a direct and reasonable comparison. The limitations of each strategy for enhancing stability of PtNi octahedral are also described. This review can serve as a valuable guide for the development of strategies to enhance the durability of octahedral PtNi.

• Clinical and Experimental Vaccine Research
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• v.12 no.3
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• pp.209-215
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• 2023

Purpose: The delay in acceptance or refusal to get vaccinated despite the availability of services is called vaccine hesitancy. The Global Polio Eradication Initiative in Pakistan faced consistent barriers preventing the eradication of the disease in the country. Similarly with the advent of the coronavirus disease 2019 (COVID-19) pandemic mass vaccination drives were initiated to a vaccine hesitant population. The aim of this study is to explore the prevalence and reasons for COVID-19 vaccine hesitancy in the Pakistani population. Materials and Methods: Cross-sectional study conducted during July to September 2021 using a snowball sampling technique targeting the adult population of Pakistan. The modified version of the vaccine hesitancy questionnaire related to the Strategic Advisory Group of Experts on Immunization Vaccine Hesitancy matrix was distributed online. Results: Out of 973 participants, 52.4% were immediately willing to take the vaccine and constituted the acceptance group whereas the remaining 47.6% who were still not sure formed the hesitant group. Support from leaders was found to be statistically significant for the difference between the hesitant and acceptance groups (p-value=0.027). Hesitant people were concerned about the effectiveness of the vaccine (60.9%) and potential side effects (57.9%) as it was not sufficiently tested prior to launch (44.7%). Age and education were significant factors affecting the acceptance of vaccination. The most trusted source of information regarding vaccination was health care workers (43.8%). Conclusion: A moderately high prevalence of vaccine hesitancy was reported in Pakistan. To overcome it, policymakers need to address the reasons for it. Leaders, celebrities, and healthcare workers can play an instrumental role in dispelling conspiracy theories regarding vaccines and making the vaccination drive a success.

• Maritime Security
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• v.7 no.1
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• pp.1-29
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• 2023

For the last 70 years, the U.S.-led bilateral security system, or "Hub-and-Spokes" system, has been applied to Northeast Asia, and the system has been successfully settled in terms of stability and economic achievements of the region. Given the increasing complexity of the security environment of East Asia, it is plausible to consider the possibility of a security system shift from bilateral alliances to collective security. In order to analyze the driver of collective security system, this study developed three factors of formation and development of collective security system - main threat, intensity of the threat, and confidence among countries in the system - by reviewing international political theories related to security cooperation. Comparing the formation, development, and achievements of NATO and SEATO, the study figures out that the existence of the main threat, the high intensity of the threat, and the strong confidence among countries in the security system are the primary drivers for a successful collective security system. Based on the result, the study also analyzed the possibility of a security system shift in East Asia. Considering contemporary international conflicts such as U.S.-China strategic competition, Russia-Ukraine War, and growing threats posed by North Korean nuclear and missiles, the study anticipates that the necessity of a collective security system that will replace the current security system of the region would arise. Still, although some issues between countries should be overcome, the growing intensity of the threats will promote cooperation among countries by improving their confidence.

• The Journal of the Convergence on Culture Technology
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• v.10 no.1
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• pp.337-344
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• 2024

This paper is a study on the "Development of Assessment Index for Women's Entrepreneurship support programs." This research highlights the absence of specific assessment indicators for selecting women-led enterprises in women's entrepreneurship support programs, thereby illuminating the limitations of current evaluation methods. It emphasizes the necessity for effective indicators to more successfully select women entrepreneurs and enterprises. The study derives numerous success factors for women's entrepreneurial ventures from prior research and develops a more likely to succeed assessment index for women-led enterprises using the Delphi methodology and collaboration with expert panels. The result is a new assessment index reflecting the characteristics of women entrepreneurs, expected to overcome the limitations of existing selection methods and contribute to enhancing social support and policy development for women-led enterprises.

• International Journal of Stem Cells
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• v.17 no.2
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• pp.102-112
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• 2024

An organoid is a self-organized three-dimensional structure derived from stem cells that mimics the structure, cell composition, and functional characteristics of specific organs and tissues and is used for evaluating the safety and effectiveness of drugs and the toxicity of industrial chemicals. Organoid technology is a new methodology that could replace testing on animals testing and accelerate development of precision and regenerative medicine. However, large variations in production can occur between laboratories with low reproducibility of the production process and no internationally agreed standards for quality evaluation factors at endpoints. To overcome these barriers that hinder the regulatory acceptance and commercialization of organoids, Korea established the Organoid Standards Initiative in September 2023 with various stakeholders, including industry, academia, regulatory agencies, and standard development experts, through public and private partnerships. This developed general guidelines for organoid manufacturing and quality evaluation and for quality evaluation guidelines for organoid-specific manufacturing for the liver, intestines, and heart through extensive evidence analysis and consensus among experts. This report is based on the common standard guideline v1.0, which is a general organoid manufacturing and quality evaluation to promote the practical use of organoids. This guideline does not focus on specific organoids or specific contexts of use but provides guidance to organoid makers and users on materials, procedures, and essential quality assessment methods at end points that are essential for organoid production applicable at the current technology level.

• Computers and Concrete
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• v.34 no.2
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• pp.247-265
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• 2024

Measuring the fracture toughness of concrete in laboratory settings is challenging due to various factors, such as complex sample preparation procedures, the requirement for precise instruments, potential sample failure, and the brittleness of the samples. Therefore, there is an urgent need to develop innovative and more effective tools to overcome these limitations. Supervised learning methods offer promising solutions. This study introduces seven machine learning algorithms for predicting concrete's effective fracture toughness (K-eff). The models were trained using 560 datasets obtained from the central straight notched Brazilian disc (CSNBD) test. The concrete samples used in the experiments contained micro silica and powdered stone, which are commonly used additives in the construction industry. The study considered six input parameters that affect concrete's K-eff, including concrete type, sample diameter, sample thickness, crack length, force, and angle of initial crack. All the algorithms demonstrated high accuracy on both the training and testing datasets, with R² values ranging from 0.9456 to 0.9999 and root mean squared error (RMSE) values ranging from 0.000004 to 0.009287. After evaluating their performance, the gated recurrent unit (GRU) algorithm showed the highest predictive accuracy. The ranking of the applied models, from highest to lowest performance in predicting the K-eff of concrete, was as follows: GRU, LSTM, RNN, SFL, ELM, LSSVM, and GEP. In conclusion, it is recommended to use supervised learning models, specifically GRU, for precise estimation of concrete's K-eff. This approach allows engineers to save significant time and costs associated with the CSNBD test. This research contributes to the field by introducing a reliable tool for accurately predicting the K-eff of concrete, enabling efficient decision-making in various engineering applications.

• Journal of Gifted/Talented Education
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• v.10 no.2
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• pp.71-86
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• 2000

According to Torrance, it is said that about 30% of feeble-headed children are bearing potential brilliant quality. Such potential gifted children exist really much more than children who appear to show their own brilliant quality. Nevertheless, research activity to reveal children's potential giftedness has not been relatively actively progressed. Renzulli, Smith and so on progresses research activity to reveal children's potential giftedness and strategies developed by them are being used widely all over the world, but these strategies show the defect that children can not overcome by themselves the interfered factors influenced negatively on their gift revelation. Russian scholar Babaeva made the effective education program to develop children's potential giftedness. Her program includes various activity methods or mental correct activity and psychological training activity and such training activity is realized through some steps and each step has it's own purpose and realization method. With the result that children discriminated as common children by the experimental study which is progressed by the present program participate, their standard of intelligence and originality showed the improved effect of the similar standard to children factors not a little influencing on children's giftedness development process but she also developed the leading concrete study method for the children to overcome this by themselves. In this paper, the present writer will examine potential giftedness development program researched in Russia and discuss their theoretic background and concrete activity course, activity result. Through this, children's have the excellent abilities in various spheres, this writer will obtain significant suggestions to educate the potential gifted children who do not display their own potentialities and do not receive a favor from gifted children program.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.3
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• pp.410-422
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• 2018

This paper studies the factors that increase the sustainability of Industry-University cooperation in the current structure of domestic I-U cooperation, which is highly dependent on government support. First, we examine the extent to which the 'I-U Relationship Strength' can be explained by the cumulative 'Experiences of I-U cooperation' and 'Width of various I-U cooperation channels', and the 'I-U cooperation barrier' can be explained by the 'Difference in mutual recognition' and 'Institutional barriers' on sustainability. In addition, the factors that can lower the 'I-U cooperation barrier', such as the 'University administration's efforts' and 'Trust between I-U', are examined. The researchers examined the factors affecting the sustainability of I-U cooperation and the factors affecting 'I-U cooperation barriers' in the 'I-U cooperation technology development projects' of the Ministry of Small & Medium Venture Business and Startups with its long history of domestic I-U cooperation programs. In order to clarify the data of the research sample, a questionnaire survey of organizational units was conducted for all companies participating in the 'I-U cooperation technology development projects' of the Ministry of SMVB and Startups between 2011 and 2015, and the responses of 356 organizations were used. It was found that the greater the 'Width of the I-U cooperation channels', the higher the sustainability and that the greater the 'Institutional barriers', the lower the sustainability. However, through the 'University administration's efforts' and 'Trust between I-U', it is possible to overcome the 'I-U cooperation barrier'. Ultimately, the systematization of Industry-University-Research institute subjects is needed to realize sustainability. In other words, it is necessary to have a linkage program that can broaden the link between industry and universities, that is to broaden the scope of I-U cooperation. Moreover, it is necessary for the government to provide institutional support to promote desirable I-U cooperation policies. Finally, it is essential to change the universities' core organizations in order to improve the level of university administration services.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.6
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• pp.249-267
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• 2021

The use of big data accumulated along with the progress of digitalization is bringing disruptive innovation to the global agricultural industry. Recently, the government is establishing an agricultural big data platform and a support organization. However, in the domestic agricultural industry, the use of big data is insufficient except for some companies in the field of cultivation and growth. In this context, this study identifies factors affecting the intention to use big data in terms of technology, organization and environment, and also confirm the moderating effect of technical field, focusing on agricultural ventures which should be the main entities in creating innovation by using big data. Research data was obtained from 309 agricultural ventures supported by the A+ Center of FACT(Foundation of AgTech Commercialization and Transfer), and was analyzed using IBM SPSS 22.0. As a result, Among technical factors, relative advantage and compatibility were found to have a significant positive (+) effect. Among organizational factors, it was found that management support had a positive (+) effect and cost had a negative (-) effect. Among environmental factors, policy support were found to have a positive (+) effect. As a result of the verification of the moderating effect of technology field, it was found that firms other than cultivation had a moderating effect that alleviated the relationship between all variables other than relative advantage, compatibility, and competitor pressure and the intention to use big data. These results suggest the following implications. First, it is necessary to select a core business that will provide opportunities to generate new profits and improve operational efficiency to agricultural ventures through the use of big data, and to increase collaboration opportunities through policy. Second, it is necessary to provide a big data analysis solution that can overcome the difficulties of analysis due to the characteristics of the agricultural industry. Third, in small organizations such as agricultural ventures, the will of the top management to reorganize the organizational culture should be preceded by a high level of understanding on the use of big data. Fourth, it is important to discover and promote successful cases that can be benchmarked at the level of SMEs and venture companies. Fifth, it will be more effective to divide the priorities of core business and support business by agricultural venture technology sector. Finally, the limitations of this study and follow-up research tasks are presented.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.11
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• pp.101-108
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• 2007

In this paper, we propose and verify an adaptive block watermarking algorithm based on JPEG2000 DWT, which determines watermarking for the original image by two scaling factors in order to overcome image degradation and blocking problem at the edge. Adaptive block watermarking algorithm uses 2 scaling factors, one is calculated by the ratio of present block average to the next block average, and the other is calculated by the ratio of total LL subband average to each block average. Signals of adaptive block watermark are obtained from an original image by itself and the strength of watermark is automatically controlled by image characters. Instead of conventional methods using identical intensity of a watermark, the proposed method uses adaptive watermark with different intensity controlled by each block. Thus, an adaptive block watermark improves the visuality of images by 4$\sim$14dB and it is robust against attacks such as filtering, JPEG2000 compression, resizing and cropping. Also we implemented the algorithm in ASIC using Hynix 0.25${\mu}m$ CMOS technology to integrate it in JPEG2000 codec chip.