• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.5
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• pp.2454-2468
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• 2019

The existing direct position determinations(DPD) for coherently distributed(CD) sources are mostly applicable for uniform linear array(ULA), which result in a low degree of freedom(DOF), and it is difficult for them to realize the effective positioning in underdetermined condition. In this paper, a novel DPD algorithm for coherently distributed sources based on compressed sensing with a moving nested array is present. In this algorithm, the nested array is introduced to DPD firstly, and a positioning model of signal moving station based on nested array is constructed. Owing to the features of coherently distributed sources, the cost function of compressed sensing is established based on vectorization. For the sake of convenience, unconstrained transformation and convex transformation of cost functions are carried out. Finally, the position coordinates of the distribution source signals are obtained according to the theory of optimization. At the same time, the complexity is analyzed, and the simulation results show that, in comparison with two-step positioning algorithms and subspace-based algorithms, the proposed algorithm effectively solves the positioning problem in underdetermined condition with the same physical element number.

• The Journal of the Korea Contents Association
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• v.7 no.9
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• pp.117-126
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• 2007

The purpose of this paper is to analyze the trends of technological development in the field of portable multimedia player (PMP) through patent information of major countries, and evaluate the technological Position of PMP. In the first place, we will carry out a quantitative analysis in terms of the annual trend of patent applications in the field of PMP, the technological position of PMP through portfolio analysis, the share of patents by applicant, the worldwide innovation leader of major countries, and the patent trend by IPC. Secondly, we will measure the technological level of PMP using indicators including cites per patent (CPP), science linkage (SL), and patent family size (PFS). Finally, we will evaluate the directions of research or technology development and the technological competitiveness of major countries. This evaluation could give us some useful policy implications on the strategy of R&D in PMP.

• Journal of Power Electronics
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• v.12 no.5
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• pp.758-768
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• 2012

This paper presents the modeling and position-sensorless vector control of a dual-airgap axial flux permanent magnet (AFPM) machine optimized for use in flywheel energy storage system (FESS) applications. The proposed AFPM machine has two sets of three-phase stator windings but requires only a single power converter to control both the electromagnetic torque and the axial levitation force. The proper controllability of the latter is crucial as it can be utilized to minimize the vertical bearing stress to improve the efficiency of the FESS. The method for controlling both the speed and axial displacement of the machine is discussed. An inherent speed sensorless observer is also proposed for speed estimation. The proposed observer eliminates the rotary encoder, which in turn reduces the overall weight and cost of the system while improving its reliability. The effectiveness of the proposed control scheme has been verified by simulations and experiments on a prototype machine.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.10a
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• pp.173-176
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• 2004

Understanding the fact that more spending for R&D is merely a necessity, not a factor of success, managing technological development efforts effectively and efficiently for higher R&D productivity and sustainable growth has become an important issue for contemporary firms. Based on a survey on small- and medium-sized manufacturing firms, this paper explores the relationships of leadership positions, technological contents and acquisition methods of korean firms. This paper has identified several findings from Korean manufacturing firms: (1) five different patterns are identified in the technology strategy of medium-sized companies; (2) a significantly positive relationship exists between a firm's leadership position and the aggressiveness in technological contents of their acquisition methods; (3) a significantly positive relationship of some technology acquisition methods to the firms' leadership position exists,

• International Journal of Advanced Culture Technology
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• v.12 no.1
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• pp.134-143
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• 2024

We investigated and analyzed the technological landscape of the global pet food industry, focusing on related industries in Korea and abroad. This industry accounts for the largest share of the rapidly growing global pet market. We aimed to identify and develop technologies that can strengthen Korea's position in this market. Our study employed various quantitative methods, including time series analysis, country and applicant analysis, and International Patent Classification (IPC) technology analysis. These analyses allowed us to objectively assess the current technological status, patent application distribution, and technological trends in the pet food industry. Our findings revealed that the United States currently holds the leading position in terms of patent applications within the pet food industry. This suggests that to establish a differentiated competitive edge in this field, it's crucial to develop technologies with high usability and target specific segments within related industries. Additionally, focusing on interdisciplinary research that combines Korea's existing advanced technologies with other relevant fields is essential.

• Journal of Korean Academy of Nursing
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• v.30 no.5
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• pp.1368-1378
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• 2000

This study was conducted to explore the nurse's perception of technological development and professional self-concept. The research subjects were 560 clinical nurses in Korea, who worked the general hospitals in Seoul, Kyeonggi, and the Kangwon province. Data sampling was done for the month, of December. 1997. The research tool consisted of 82 items questionnaires which were demographic data, TIQ, PSCNI. The research findings were as follows: 1. Nurses perceived the technological development as slightly positive (Mean =48.8). Also, nurses saw that the fastest developing technological nursing unit was the cardiac care unit, while the lowest technological developing nursing unit was the psychiatric unit. 2. The view of technological development was found to be significantly different according to religion (P=.0109), marital status (P=.0431), and the practical setting (P=.0048). Professional self concept was significantly different according to age (P=.0001), religion (P=.0001), education (P=.0007), marital status (P=.0000), career (P=.0001), and position (P=.0000). 3. The relationship between a nurse's perception of technological development and professional self-concept was highly correlated(r=.26, P=.0001). In the results of the multiple regression, the factors influencing professional self-concept were career, the nurse's perception of technological development, the level of technological development in nursing unit, and education. All these parameters showed the explaining power of 15.4% of the professional self-concept. In conclusion, nurses recognized the technological development was related to the professional self-concept. This study shed light on the meaning of technological development and vision of the nursing profession. Inservice education program should be developed to help the adaptability to technological development and conduct the qualitative research to explore the world of technological development which the nurses are experiencing in nursing.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.5
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• pp.2332-2338
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• 2011

The economy of the EU left behind the U. S. economy in many different aspects and the gap is widening. One major reason that promoted the EU's leading position is the ability to continuously advancing industrial technology and therefor secures the EU's leading position through a high level of competitiveness. The role as a powerhouse of the technological development is nurtured by a systematic attempt of the EU commission to stimulate international cooperation. Although the EU is focussing its efforts on international cooperation between EU members states, nonmembers, namely Korea, can benefit from this policy as well and generate win-win outcomes for both cooperating partners. The paper aims in the first chapter to introduce international technological cooperations in general. The second chapter identifies the political approach of both countries towards technological cooperations. The third chapter introduces the research method. In the forth chapter is analyzed a case study of two cooperation projects between Japan and the EU. Finally, implications for Korean policy makers are given.

• STI Policy Review
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• v.8 no.1
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• pp.113-156
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• 2017

Although technological progress is considered a key element for economic growth and development of a country, strong empirical evidence in this regard is not available yet. Therefore, to establish the empirical link between technology progress and economic development, it is advisable to carry out a time series analysis. In this regard, the Technology Achievement Index (TAI) of 100 top economies has been developed to examine the position of countries' technological progress for the 21 years spanning 1995 to 2015. Countries have been ranked on their TAI which is based on four pillars; technology creation, diffusion of older innovations, diffusion of recent innovations, and development of human skills. As well, this current study re-calculates the Humane Development Index (HDI) of 100 top economies for the 21 years from 1995 to 2015. Ranking of countries' HDI values reflects three dimensions: A long lifespan (life expectancy index), knowledge (Education Index) and a decent standard of living (Gross National Income Index, or GNI). The Standard Deviation (SD) technique has been used to investigate the technological gap between individual countries and groups of countries or regions. For a more meaningful assessment, technological gaps from the maximum achievement value (i.e., one of the countries under study) are presented as well. To investigate the impact of technological progress on economic development, this study introduces a model in which the HDI is used as the dependent variable and the TAI and Gross Capital Formation (GCF) are used as independent variables. The HDI, TAI and GCF are used in this model as proxy variables for economic development, technological progress and capital respectively. Econometric techniques have been used to show the impact of technological progress on economic development. The results show that long-term associations exist between technology progress and economic development; the impact of technology progress on economic development is 13.2% while the impact is 4.3% higher in eight selected East South Asian countries, at 13.5%, than in eight selected highly developed countries (9.2%).

• IEIE Transactions on Smart Processing and Computing
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• v.2 no.5
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• pp.266-276
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• 2013

LSB-based steganography is a simple and well known information hiding technique. In most LSB based techniques, a secret message is embedded into a specific position of LSB in the cover pixels. On the other hand, the main threat of LSB-based steganography is steganalysis. This paper proposes an asynchronous-cellular-automata(ACA)-based steganographic method, where secret bits are embedded into the selected position inside the cover pixel by ACA rule 51 and a secret key. As a result, it is very difficult for malicious users to retrieve a secret message from a cover image without knowing the secret key, even if the extraction algorithm is known. In addition, another layer of security is provided by almost random (rule-based) selection of a cover pixel for embedding using ACA and a different secret key. Finally, the experimental results show that the proposed method can be secured against the well-known steganalysis RS-attack.

• Structural Engineering and Mechanics
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• v.13 no.1
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• pp.1-16
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• 2002

This paper presents the findings of an investigation carried out to determine the most appropriate connections, in terms of rotational stiffness, to use for the optimum design of cold-formed Zed section sleeve joint purlin system. Experiments and parametric studies were conducted to investigate the effects of geometric variables on the behavior of the sleeve-purlin and cleat-purlin connections of the sleeve joint purlin system. The variables considered were purlin size and thickness, sleeve size, thickness, length and bolt position. The test results were used to verify the empirical expressions, developed herein, employed to determine the rotational stiffness of connections. With the predicted connection stiffness, the most suitable sleeve-purlin and cleat-purlin connections can be selected so as to produce an optimum condition for the sleeve joint purlin system.