• International Journal of Contents
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• 제11권4호
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• pp.38-43
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• 2015

Non-orthogonal multiple access (NOMA) where all users share the entire time and frequency resource has paid attention as one of the key technologies to enhance the spectral efficiency and the total throughput. Nevertheless, as the number of users and SIC error increase, the inter-user interference and the residual interference due to the SIC error also increase, resulting in performance degradation. In order to mitigate the performance degradation, we propose grouping-based NOMA system. In the proposed scheme, all users are divided into two groups based on the distance between the BS and each user, where one utilizes the first half of the bandwidth and the other utilizes the rest in the orthogonal manner. On the other hand, users in each group share the spectrum in the non-orthogonal manner. Grouping users can reduce both the inter-user interference and residual interference due to the SIC error, so it can outperform conventional NOMA system, especially in case that the number of users and the SIC error increase. Based on that, we also present the hybrid operation of the conventional and the proposed NOMA systems. In numerical results, the total throughput of the proposed NOMA systems is compared with that of the conventional NOMA systems with regard to the number of users and SIC error. It is confirmed that the proposed NOMA system outperforms the conventional NOMA system as the number of users and the SIC error increase.

• ETRI Journal
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• 제25권4호
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• pp.258-265
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• 2003

In our study, we extracted the market, finance, and government factors determining R&D investment of individual firms in the IT industry in Korea. We collected the financial data of 515 individual firms belonging to IT and non-IT industries between 1980 and 1999 from the Korea Investors Service's database and investigated the empirical relationship between the factors using an ordinary regression model, a fixed effects model, and a random effects model. The main findings of our study are as follows: i) The Herfindahl Index variable representing the degree of market concentration is statistically insignificant in explaining R&D expenditures in the IT manufacturing industry. ii) Assets, which is used as a proxy variable for firm size, have a positive and statistically significant coefficient. These two results suggest that the Schumpeterian Hypothesis may be only partially applied to the IT manufacturing industry in Korea. iii) The dividend variable has a negative value and is statistically significant, indicating that a tendency of high dividends can restrict the internal cash flow for R&D investment. iv) The sales variable representing growth potential shows a positive coefficient. v) The subsidy as a proxy variable for governmental R&D promotion policies is positively correlated with R&D expenditure. This suggests that government policy has played a significant role in promoting R&D activities of IT firms in Korea since 1980. vi) Using a dummy variable, we verified that firms reduced their R&D investments to secure sufficient liquidity under the restructuring pressure during Korea's 1998 and 1999 economic crisis.

• The Journal of Asian Finance, Economics and Business
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• 제8권8호
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• pp.1-12
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• 2021

Altman's Z-score is used to measure a company's financial health and to predict the probability that a company will collapse within 2 years. It is proven to be very accurate to forecast bankruptcy in a wide variety of contexts and markets. The goal of this study is to use Altman's Z-score model to forecast insolvency in non-financial publicly traded enterprises. Non-financial firms are a significant industry in Malaysia, and current trends of consolidation and long-term government subsidies make assessing the financial health of such businesses critical not just for the owners, but also for other stakeholders. The sample of this study includes 84 listed companies in the Kuala Lumpur Stock Exchange. Of the 84 companies, 52 are considered high risk, and 32 are considered low-risk companies. Secondary data for the analysis was gathered from chosen companies' financial reports. The findings of this study show that the Altman model may be used to forecast a company's financial collapse. It dispelled any reservations about the model's legitimacy and the utility of applying it to predict the likelihood of bankruptcy in a company. The findings of this study have significant consequences for investors, creditors, and corporate management. Portfolio managers may make better selections by not investing in companies that have proved to be in danger of failing if they understand the variables that contribute to corporate distress.

• 디지털융복합연구
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• 제19권9호
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• pp.201-207
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• 2021

인공지능이 점차 직무에 확대됨에 따라 비전공자에게 요구되는 AI 리터러시 역량을 갖춘 인재 육성이 필요하다. 이에 본 연구에서는 AI 교육의 필요성 및 현황을 기반으로 향후 전공과 관련하여 AI 학습이 지속 가능하도록 비전공자에 맞는 AI 리터러시 역량 향상 교육을 실시하였다. D 대학의 비전공자를 대상으로 프로젝트 기반 데이터 분석과 시각화를 통한 문제 해결방안 도출을 15주에 걸쳐 적용하고, 학습자들의 교육 전후에 대한 AI 능력 향상 및 효과성을 분석하여 검증하였다. 그 결과, 학습자들의 데이터 분석 및 활용 능력, AI 리터러시 능력, AI 자기효능감 부분에서 통계적으로 유의미한 수준의 긍정적 변화를 확인할 수 있었다. 특히, 학습자들에게 공공데이터를 직접 활용하여 분석하고 시각화하는 능력뿐만 아니라 이를 AI 활용과 연결하여 문제를 해결할 수 있는 자기효능감까지 향상시켰다. 이는 비전공자의 AI 교육에 매우 유용하고 효과성이 있음을 확인할 수 있다. 향후 본 연구를 바탕으로 AI 활용을 확장하여 데이터와 AI 기술을 일상 속에서 자유롭게 활용 가능하도록 다양한 계열의 비전공자에 맞는 확장된 AI 교육 과정 연구를 진행할 예정이다.

• International Journal of Advanced Culture Technology
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• 제8권4호
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• pp.18-24
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• 2020

The Korea Textile and Fashion Industry-Academic Association, which was established in 2004, has been operating without its own homepage until now. In 2019, it was judged that it was urgent to manage new members and build an installed homepage. Therefore, the program provided by 'I'mweb' was used by comparing domestic and overseas website manufacturers, and the reason is as follows. First, 'I'mweb' provides a web builder solution that allows individuals to easily create web sites without IT expertise such as program development, use of photoshop, and coding. Second, it faithfully provides bulletin boards and member management functions necessary in Korea, such as internet homepage builders and shopping mall production services. Third, there is an advantage in that it is easy to manage the homepage because it is convenient to use Q&A service through the administrator when building the web. However, it provides a responsive web function, but it is regrettable that the compatibility between PC and mobile is not smooth. This study is expected to be used as basic data for related research that needs help in opening a website in the future.

• Fisheries and Aquatic Sciences
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• 제3권1호
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• pp.52-63
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• 2000

Non-specific reaction has been a problem in doing, especially, research and diagnosis for infectious agents. Avidin-biotin-peroxidase complex (ABC) techniques has widely been used to amplify a reaction. Photobacterium damse1a subsp. piscicdia (formerly Pasteurella piscicida) exhibited a capacity to bind with streptavidin non-specifically. The band, estimated 26 K Da in Western blotted paper, was blocked with biotin but incompletely. In an attempt to explore an involvement of the non-specific substance in attaching piscine cells, cell attachment test performed using anti- Ph. d. subsp piscicida sera raised mouse and rabbit exhibited slightly blocking effects for Mediterranean (1736) and significantly for Japanese (Sp 92144) isolate. Biotin decreased the attachment ability significantly for Sp92144 but it was not effective to 1736. Both isolates showed greatly enhanced attachment ability with poly-L-lysin. The non-specific binding substance was contained in bacterial extracellular products (ECPs). The substance was able to purified with 2-imminobiotin affinity column, the purified substance appeared to have 4 bands in silver staining, and had a carbohydrate branch. This purified substance showed cytotoxic effects selectively between 5 piscine cell lines. Moreover, it stimulated rainbow trout macrophage in terms of reduction of cytochrome cas well as yeast phagocytosis, significantly.

• 한국산업융합학회 논문집
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• 제25권2_2호
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• pp.199-208
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• 2022

The steel wire or steel bar processing process applied to the manufacture of various bolts and power transmission shafts was improved by applying in-line phosphate film treatment technology. By applying a polymer lubricant for a non-reactive metal forming process and a non-reactive non-phosphorus lubricating coating agent, the film formation for each process time was comparatively analyzed and reviewed. Compared to the nine processes applied previously, the in-line phosphate film treatment technology applied with only two processes has been effectively improved in terms of reduction of treatment time, reduction of facility installation area, prevention of water pollution due to wastewater, and non-use of ozone-depleting substances. In addition, it was found that it can have an important effect on productivity improvement and price competitiveness from the simplification of quality control and process control as well as improvement of the working environment.

• 무역학회지
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• 제46권4호
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• pp.113-130
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• 2021

This study aims to analyze the WTO-inconsistent aspects of the single rate presumption of the United States in establishing and imposing anti-dumping duties for non-market economy exporters. By examining the drafting history in the GATT/WTO negotiations and the practice of the single rate presumption for non-market economies by the United States from a comparative perspective, it critically addresses the inherent lack of pertinent disciplines under the framework of the WTO Anti-Dumping Agreement in establishing dumping margins for exporters of non-market economies. The WTO Dispute Settlement Body leaves open the possibility of allowing the investigating authority to consider multiple exporters and the exporting country as a single entity. However, the study argues that it is difficult in practice for the investigating authority to make a single-entity decision in a WTO-consistent manner. The study also finds an incompatibility in the notion between establishing dumping margins for 'individual' exporters and 'non-market economies.' A proper discipline for non-market economies under the multilateral anti-dumping norm needs to be reconsidered in the era of persistent trade conflicts between the United States and China.

• 대한수학회보
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• 제22권2호
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• pp.89-93
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• 1985

One of the most important problems in automatic continuity theory is to solve the question of continuity of an algebra homomorphism from a Banach algebra into a semisimple Banach algebra with dense range. Many results on this subject are obtained imposing some conditions on the domains or the ranges of homomorphisms. For most recent results and references in automatic continuity theory one may refer to [1], [4] and [5]. In this note we study some properties of homomorphisms from $C^{*}$-algebras into Banach algebras. It is shown that the range of an isomorphism from a $C^{*}$-algebra into a Banach algebra contains no non zero element of the radical of B. Using this result we show that the same holds for a continuous homomorphism, hence a Banach algebra which is the image of a $C^{*}$-algebra under a continuous homomorphism is necessarily semisimple. Thus if there is a homomorphism from a $C^{*}$-algebra onto a non-semisimple Banach algebra it must be discontinuous. Also it follows that every non zero homomorphism from a $C^{*}$-algebra into a radical algebra is discontinuous. Then we make a brief observation on the behavior of quasinilpotent element of noncommutative $C^{*}$-algebras in relation with continuous homomorphisms.momorphisms.

• 한국전산유체공학회지
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• 제17권2호
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• pp.65-70
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• 2012

The droplet ejection behavior from drop-on-demand printhead are investigated numerically in terms of the non-dimensional parameters. The numerical simulation is performed using a volume-of-fluid model. It is important to eject droplet within the printability range, where the droplet is ejected in stable manner without satellite droplets. Generally, the printability range has been determined by Z number, which is the inverse of Oh number. However, it is found that the ejection of droplets with same Z number can exhibit different behavior depending on the value of Ca and We number. Therefore, it is insufficient to determine the printability range only with Z number. Instead, other non-dimensional parameters, such as Ca and We number, should be considered comprehensively.