• Carbon letters
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• v.13 no.1
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• pp.17-22
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• 2012

Currently, graphene is a topic of very active research in fields from science to potential applications. For various radio-frequency (RF) circuit applications including low-noise amplifiers, the unique ambipolar nature of graphene field-effect transistors can be utilized for high-performance frequency multipliers, mixers and high-speed radiometers. Potential integration of graphene on Silicon substrates with complementary metal-oxide-semiconductor compatibility would also benefit future RF systems. The future success of the RF circuit applications depends on vertical and lateral scaling of graphene metal-oxide-semiconductor field-effect transistors to minimize parasitics and improve gate modulation efficiency in the channel. In this paper, we highlight recent progress in graphene materials, devices, and circuits for RF applications. For passive RF applications, we show its transparent electromagnetic shielding in Ku-band and transparent antenna, where its success depends on quality of materials. We also attempt to discuss future applications and challenges of graphene.

• BMB Reports
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• v.55 no.5
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• pp.213-219
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• 2022

The blood-brain barrier (BBB) is an interface between cerebral blood and the brain parenchyma. As a gate keeper, BBB regulates passage of nutrients and exogeneous compounds. Owing to this highly selective barrier, many drugs targeting brain diseases are not likely to pass through the BBB. Thus, a large amount of time and cost have been paid for the development of BBB targeted therapeutics. However, many drugs validated in in vitro models and animal models have failed in clinical trials primarily due to the lack of an appropriate BBB model. Human BBB has a unique cellular architecture. Different physiologies between human and animal BBB hinder the prediction of drug responses. Therefore, a more physiologically relevant alternative BBB model needs to be developed. In this review, we summarize major features of human BBB and current BBB models and describe organ-on-chip models for BBB modeling and their applications in neurological complications.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.2
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• pp.22-29
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• 2013

The platform safety door is difficult to install in platform because the doors of railway vehicles and existing Passenger Safety doors should be alined. To be able to solve this problem, we propose the use of Rope Type Platform Safe Door (RPSD) which is a vertically retractable platform that is designed to close from top to bottom. This platform has installed safety gate pillars at intervals of 20-40 m which accommodates different types of train regardless of train length, gate opening and location. In this paper, we reviewed the application of existing PSD and RPSD in various train stops in Seoul Gyeongbu Line platform. The results of the review showed that the existing PSD may cause problem in construction, safety and cost efficiency. The use of RPSD however shows that minimal problems will be encountered.

• Transactions on Electrical and Electronic Materials
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• v.11 no.4
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• pp.155-165
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• 2010

As a promising candidate to replace the conventional floating gate flash memories, polysilicon-oxide-nitride-oxidesilicon (SONOS)-type nonvolatile semiconductor memories have been investigated widely in the past several years. SONOS-type memories have some advantages over the conventional floating gate flash memories, such as lower operating voltage, excellent endurance and compatibility with standard complementary metal-oxide-semiconductor (CMOS) technology. However, their operating speed and date retention characteristics are still the bottlenecks to limit the applications of SONOS-type memories. Recently, various approaches have been used to make a trade-off between the operating speed and the date retention characteristics. Application of high-k dielectrics to SONOS-type memories is a predominant route. This article provides the state-of-the-art research progress of high-k dielectrics applicable to SONOS-type nonvolatile semiconductor memories. It begins with a short description of working mechanism of SONOS-type memories, and then deals with the materials' requirements of high-k dielectrics used for SONOS-type memories. In the following section, the microstructures of high-k dielectrics used as tunneling layers, charge trapping layers and blocking layers in SONOS-type memories, and their impacts on the memory behaviors are critically reviewed. The improvement of the memory characteristics by using multilayered structures, including multilayered tunneling layer or multilayered charge trapping layer are also discussed. Finally, this review is concluded with our perspectives towards the future researches on the high-k dielectrics applicable to SONOS-type nonvolatile semiconductor memories.

• Korean Institute of Interior Design Journal
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• v.14 no.4 s.51
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• pp.95-105
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• 2005

To plan more effective exhibitions, exhibitions should be evaluated and verified through research. This is Important in that it will present measures for improving shortcomings in exhibition goals and procedures; and it will also provide new ideas and goals for future exhibition plans. The purposes of this study are to investigate the applicability of evaluation methods by organizing related theories systematically through a literature review and to provide more practical and valuable information about the methods by applying them to actual museums. For this study, the National Science Museum was investigated since it uses various themes and exhibition methods, compared with other science museums. Exhibition structures and presentation formats were first analyzed, and then the methods of trace and observation were used to investigate how visitors use the museum. Surveys were also conducted at two different times. The results of the analyses showed that problems of exhibits, arrangement methods of exhibition space, or guide systems are more prominent than those of the presentation format itself. Based on these results, measures for improvement are suggested as follows: First, new formats of exhibition halls using new window frames or holes should be explored to stimulate visitors' curiosity and to lead viewing traffic flow in the museum. Second, in presenting representative exhibits, a gate can be installed at each exhibition area, and representative exhibits are displayed by the gate or between exhibition booths. Third, if a small space is provided at the end of each exhibition area, it can be used to give an orientation on the next exhibition or used as a resting place.

• The Journal of Society for e-Business Studies
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• v.27 no.1
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• pp.15-28
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• 2022

Due to recent expansion of online market such as clothing, utilizing customer review has become a major marketing measure. User review has been used as a tool of analyzing sentiment of customers. Sentiment analysis can be largely classified with machine learning-based and lexicon-based method. Machine learning-based method is a learning classification model referring review and labels. As research of sentiment analysis has been developed, multi-modal models learned by images and video data in reviews has been studied. Characteristics of words in reviews are differentiated depending on products' and customers' categories. In this paper, sentiment is analyzed via considering review data and metadata of products and users. Gated Recurrent Unit (GRU), Long Short-Term Memory (LSTM), Self Attention-based Multi-head Attention models and Bidirectional Encoder Representation from Transformer (BERT) are used in this study. Same Multi-Layer Perceptron (MLP) model is used upon every products information. This paper suggests a multi-modal sentiment analysis model that simultaneously considers user reviews and product meta-information.

• Journal of Navigation and Port Research
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• v.30 no.6 s.112
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• pp.499-508
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• 2006

Many changes lie ahead for Korea both domestically and internationally including opening of Busan New Port, more active Gwangyang Port as well as rapid growth of Shanghai Port and enhanced services and productivity at Shenzen Port. Compared to newer ports, container terminals in Busan Port possesses old equipment and facilities. Therefore, in order for Busan Port to maintain its service level and remain competitive, it needs to undergo remodeling to enhance productivity. Remodeling activities should be implemented on a continual basis by developing and applying new technologies such as those for gate system, berth system, yard system, and IT system In order to review the alternatives, we performed questionnaire survey and interview. From the result of analysis, we designed the application plan based on priority in remodeling, period of technology application, and direction for application.

• Journal of the Korean Institute of Landscape Architecture
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• v.35 no.3
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• pp.92-104
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• 2007

This paper aims to discussion the characteristics of location and spatial organization on Hongneung and Yureung(royal tomb) in Namyangju through the interpretation of traditional oriental philosophy including Feng-Shui theory. To do this, we studied in two ways; analysis of the present conditions and photographing research materials about the form of physical structure and review of historical document. The result of analysis in sight of the location and spatial structure was good matched. Main finding of this paper are as follows: The location and landscape structure was characterized by the harmony with natural following traditional thinking and the Korean view of nature, while maintaining the dignity of the King. The spatial organization were placed in a straight line following the hierarchy of metaphysics by order of Neungchim(Tombs Vicinity) - Changmyungdeung(Stone Lantern) - Chungjakak(Pavilion) - Hongsalmun(Gate for Heavenly Gods) and was based on the Confucianism value, the natural contour and inner value. Through this study, we find the principles made it possibles to re-evaluate nature in modem society and provided us with new ways to conserve nature with the help of environmental theory.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6087-6091
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• 2012

Context: Patients diagnosed with a cancer have a life time risk of developing another de novo malignancy depending on various inherited, environmental and iatrogenic risk factors. Of late the detection of new primary has increased mainly due to refinement in both diagnostic and treatment modalities. Cancer victims are surviving longer and thus are more likely to develop a new metachronous malignancy. Aims: To report our observed trend of increase in prevalence of both synchronous and metachronous second malignant neoplasms among cancer victims and to review the relevant literature. Settings and Design: A hospital based retrospective collection of prospective data of patients diagnosed with second denovo malignancy. Materials and Method: The study was conducted over a 5 year period from July 2008 to June 2012. All patients diagnosed with a histologically proven second malignancy as per Warren Gate's criteria were included. Various details regarding sex, age at presentation, synchronous or metachronous, treatment and outcome were recorded. Conclusions: The occurrence of multiple primary malignancies is not rare. Awareness of the possibility alerts the clinician in evaluation of patients with a known malignancy presenting with unusual sites of metastasis. Individualizing the treatment according to the stages of the primaries will result in durable cancer control particularly in synchronous double malignancy.

• Journal of the Korean housing association
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• v.27 no.3
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• pp.23-30
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• 2016

Among the unearthed House ruins in Gyeongju of the capital of Silla period, the ruins to see the overall appearance of building arrangement is the ruins of Silla capital S1E1 area, Inwangdong 412, and the Jaemaejeong. In this study, the characteristics of urban house arrangement of the Unified Silla period was analyzed that, through a review of the arrangement relationship between the gate and the individual buildings found in these ruins. The urban house of the Unified Silla period was surrounded with wall, and the way to distinguish between functional areas within it are shown differently, depending on the size of the house. In other words, the small house was divided each area by installation of inner fence, and the large house was by arranging attached buildings. Thai is, the central area is not divided by inner fence is the Characteristics that is different from the small house. And in all houses, a large courtyard is located in the front of main building. Conatruction of the courtyard determines the location and direction of the main building. And the each area has external space of courtyard in the center.