• Journal of Power Electronics
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• v.16 no.1
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• pp.163-172
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• 2016

The modular multilevel converter (MMC) has been receiving increased attentions in recent years. The new modular multilevel converter is a derivative topology from the traditional MMC in which the number of sub-modules (SMs) necessitated by each phase can be reduced by one. This paper presents a phase-shifted carrier pulse-width modulation (PSC-PWM) for the new MMC with an optimal phase-shifted angle to suppress the harmonics of the output voltage. Further, the harmonic features when the capacitor voltage of the middle SM is selected as two different values are also investigated. Moreover, in order to avoid introducing an unnecessary dc offset current at the ac terminals of the new MMC, a novel capacitor voltage balancing scheme is proposed by adjusting the amplitude of the reference signals rather than the offset. Finally, the validity and effectiveness of the proposed modulation and balancing schemes have been verified by experimental results based on a three-phase prototype of the new MMC.

• Journal of Korea Technology Innovation Society
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• v.7 no.1
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• pp.64-88
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• 2004

This paper aims at investigating which factors play important roles in selecting government's new core IT industries and how competitive they are. We surveyed 6 competitiveness factors and 17 IT industries for the expert group. The logit and probit models were estimated and SWOT analysis was performed. The empirical results show that government put emphasis on marketability, externality and technology, not publicity, when selecting IT new core industry. The skilled human resources turn out to be a threat factor in the government selected IT new core industries such as home-network, third generation semi-conductor. Therefore, training or education system for skilled labors is required to develop and nurture such industries. The contribution to small medium venture industry and publicity are lower in the several industries such as intelligent service robots, post PC, embodied S/W, next generation battery, which are selected by government, not by standardized data based criterion. in such industries, marketabilities, technology, skilled human resources are threats factors to such industries. Therefore every effort for enhancing the marketability and R&D investment and education system for skilled labor are necessary to develop the industries.

• Imaging Science in Dentistry
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• v.51 no.4
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• pp.455-460
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• 2021

This report presents a rare case of maxillary osteoblastoma in a 17-year-old female. The patient presented with dull pain and facial asymmetry inferior to the left zygoma. An intraoral examination found a painless swelling on the buccal gingival tissue in the left posterior maxilla. Panoramic radiographs and multidetector computed tomographic images revealed an ill-defined, non-corticated, mixed attenuating entity of osseous density located within the left posterior maxilla apical to the left maxillary molars. The entity exhibited a heterogeneous internal structure with a fine granular appearance, and the periphery showed a partial hypo-attenuating rim along the antero-medial aspect. Expansion of the left posterior maxilla accompanied with displacement of the left maxillary sinus floor was noted. External root resorption of the first and second molars was noted, as well as postero-superior displacement of the third molar. The histopathologic diagnosis of the biopsy was osteoblastoma. Complete excision of the tumor was performed.

• IE interfaces
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• v.19 no.2
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• pp.140-152
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• 2006

Today, many companies realize that the effort to develop new products / services faster that customers want and continue to purchase is crucial for their survival. As the service sector is rapidly growing, one of the challenges faced by the service industries is the lack of effective methodologies for new service development. This paper proposes a systematic framework for developing new service concepts, with an emphasis on generating innovative, convergence-type service concepts from the customer‘s perspective. The framework consists of three phases-identification of customer needs (Phase I), extraction of new service opportunities (Phase II), and generation of new service concepts (Phase III). The proposed framework is demonstrated through a case study in the telecommunications industry. In the case study, a survey was conducted on ten customers to identify the latent customer needs; 61 new service opportunities were extracted; and 129 new service concepts were generated.

• Journal of The Korean Astronomical Society
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• v.51 no.3
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• pp.65-71
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• 2018

The near real-time speckle masking reconstruction technique has been developed to accelerate the processing of solar images to achieve high resolutions for ground-based solar telescopes. However, the reconstruction of solar subimages in such a speckle reconstruction is very time-consuming. We design and implement a new parallel speckle masking reconstruction algorithm based on the Compute Unified Device Architecture (CUDA) on General Purpose Graphics Processing Units (GPGPU). Tests are performed to validate the correctness of our program on NVIDIA GPGPU. Details of several parallel reconstruction steps are presented, and the parallel implementation between various modules shows a significant speed increase compared to the previous serial implementations. In addition, we present a comparison of runtimes across serial programs, the OpenMP-based method, and the new parallel method. The new parallel method shows a clear advantage for large scale data processing, and a speedup of around 9 to 10 is achieved in reconstructing one solar subimage of $256{\times}256pixels$. The speedup performance of the new parallel method exceeds that of OpenMP-based method overall. We conclude that the new parallel method would be of value, and contribute to real-time reconstruction of an entire solar image.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2687-2692
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• 2003

Recent advancement in information technology requires new interpretations for the space among human, machines and environment. Investigation of space between information and human could lead to the proper ways, in which human and machines meet. Various concepts regarding space have been explored in terms of “virtual reality in cyberspace” and “embodiment in tangible space.” “Mom (embodiment),” space, virtuality, sensation/perception, and interactive technology are some of the key ideas to be explored. Human “Mom” is such a fundamental membrane through which human can interact with the environment physically and mentally. An embodied interaction paradigm, based on “Mom,” is investigated. This leads to interactive technology paradigm. Sound space is an invisible but a tangible space in a sense that it travels in emotional tremors and stimulates new sensations and perceptions. Three cases are introduced to experiment such tangible space as a new and proper interactive paradigm. Also, a historical model of interaction is reviewed, which includes electrical, symbolic, textual, graphical, tangible, and social interaction.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.802-806
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• 2007

There has been growing interest in the antioxidative and anticarcinogenic effects of vegetables. This study was aimed at evaluating the antioxidative and antiproliferative activities of 13 leafy vegetables consumed in Korea. New-beet and ornamental kale contained >1,000 mg of polyphenolics/100g fresh weight (FW), which was the greatest amount among the test vegetable extracts. Ornamental kale also contained the greatest amount (232.84 mg/100g FW) of flavonoids. With the exception of chicory, values of 1.1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activities showed similar trends. New-beet was found to be the greatest antioxidant among the test vegetable extracts. New-beet exhibited the highest antiproliferative activity (>60%) against all tumor cells. No relationship was found between antiproliferative activity and antioxidant contents or antioxidant activities among samples.

• Journal of Information Processing Systems
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• v.5 no.2
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• pp.87-96
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• 2009

Grid computing is a new technology which involves efforts to create a huge source of processing power by connecting computational resources throughout the world. The key issue of such environments is their resource allocation and the appropriate job scheduling strategy. Several approaches to scheduling in these environments have been proposed to date. Market driven scheduling as a decentralized solution for such complicated environments has introduced new challenges. In this paper the bidding problem with regard to resources in the reverse auction resource allocation model has been investigated and the new bidding strategies have been proposed and investigated.

• Journal of Contemporary Eastern Asia
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• v.18 no.2
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• pp.1-8
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• 2019

The blockchain is still new and unfamiliar. But blockchain appears to shake an entire technology innovation system. Blockchain is rapidly drawing attention in that it will be able to fundamentally revolutionize industry ecosystem. While cryptocurrency transactions and market capitalization have been popular in mass media, several platform operators in non-cryptocurrency areas such as jewelry, social networks, and entertainment, are also moving to introduce blockchain technology in full swing. In this brief note, we intend to present integrated theoretical strands to summarize various prospects for blockchain technology. Further, we want to provide a reflection as to whether this new technology gives opportunities, challenges, or risks to future society. Particularly, we point out one of its alternative and promising adoption that gives way to new forms of decentralized and autonomous organizations (DAOs).

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.08a
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• pp.261-267
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• 2004

Current steel makers are trying to develop new manufacturing process to secure price competition and to improve productivity by testing a various kinds of rolling condition of several kinds of steel at TCM. Accordingly, Reverse Mill operation for Stainless steel is changing to TCM operation and furthermore, even general carbon steel and electric steel plate are requested to be worked at TCM simultaneously. By these changing of rolling condition, it become to be necessary to develop new water-soluble cold rolling oil that has a characteristics to be suitable for various working condition and in this report, we would like to mention lubrication condition to fulfill requested characteristics of each steels and development and applying result of multi-purpose water-soluble cold rolling oil which has such an lubrication property.