• Title/Summary/Keyword: science network

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Visibility Analysis of Iridium Communication for SNIPE Nano-Satellite (SNIPE 초소형위성용 Iridium 통신 모듈의 가시성 분석)

  • Cho, Dong-Hyun;Kim, Hongrae;Kim, Hae-Dong
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.50 no.2
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    • pp.127-135
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    • 2022
  • Compared to the continuous increase of domestic nano-satellite development cases, the initial communication success rate is relatively low. In a situation where communication cases of LEO satellites using commercial satellite communication networks are increasing recently. In this situation, the SNIPE project developed by the KASI(Korea Astronomy and Space Science Institute), KARI(Korea Aerospace Research Institute), and Yonsei University apply an Iridium module for communication test to the SNIPE nano-satellites. Therefore, in this paper, the visibility analysis of the iridium module on the SNIPE satellite was analyzed under considering the orbital and communication environment of the iridium satellite constellation and the attitude control mode. In the case of LEO satellites, the communication possibility was limited due to the relatively small iridium communication coverage for high altitude and the high doppler shift considered in the iridium communication network. For this reason, in this paper, it could be simulated that there was a more performance difference according to the difference in relative RAAN(Right Ascension of Ascending Node) angle with the Iridium constellation. Finally, by checking the visibility of communication module under the tumbling situation that occurred during the initial deployment of the nano-satellite, the possibility of using the iridium communication technology was analyzed.

Research on the Dynamic Application of Cultural and Creative Products based on Museum Resources (박물관 자원에 기초한 문화 창작물의 활성화 응용 연구)

  • Qi, xiao;Pan, Younghwan;Jang, Wan-Sok
    • Journal of the Korea Convergence Society
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    • v.13 no.2
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    • pp.151-166
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    • 2022
  • Museum is the carrier and symbol of history and cultural accumulation, and the museum cultural relics are clues with the spirit of history. Moreover, the museum cultural and creative products are portable history. Museum has changed form the traditional "object-basic" model to the modern "people-basic" model, which pays more attention to its living inheritance. Therefor, the museum cultural and creative products is also the way of expression of its living inheritance. This paper analyzes the opportunities and difficulties of cultural and creative products of Chinese museums by means of network survey, field survey and expert interview. In order to improve the design method of cultural and creative products. By exploring the cultural connotation, broadening the functional factors, innovating the design factors and creating the empathy factor between products and people to explore and the verify. Trying to make up the imperfect design methods of cultural and creative products in small and medium-sized museums which leads to the lack of function, innovation and communication of cultural and creative products. We try to attract more people's attention, spread traditional culture and realize the resonance between people and objects.

Integrated receptive field diversification method for improving speaker verification performance for variable-length utterances (가변 길이 입력 발성에서의 화자 인증 성능 향상을 위한 통합된 수용 영역 다양화 기법)

  • Shin, Hyun-seo;Kim, Ju-ho;Heo, Jungwoo;Shim, Hye-jin;Yu, Ha-Jin
    • The Journal of the Acoustical Society of Korea
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    • v.41 no.3
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    • pp.319-325
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    • 2022
  • The variation of utterance lengths is a representative factor that can degrade the performance of speaker verification systems. To handle this issue, previous studies had attempted to extract speaker features from various branches or to use convolution layers with different receptive fields. Combining the advantages of the previous two approaches for variable-length input, this paper proposes integrated receptive field diversification that extracts speaker features through more diverse receptive field. The proposed method processes the input features by convolutional layers with different receptive fields at multiple time-axis branches, and extracts speaker embedding by dynamically aggregating the processed features according to the lengths of input utterances. The deep neural networks in this study were trained on the VoxCeleb2 dataset and tested on the VoxCeleb1 evaluation dataset that divided into 1 s, 2 s, 5 s, and full-length. Experimental results demonstrated that the proposed method reduces the equal error rate by 19.7 % compared to the baseline.

The Empathy and Justice Contemplated From the Neuroscientific Perspective in the Age of Social Divisions and Conflicts (분열과 반목의 시대에 신경과학적 관점에서 고찰해보는 공감과 정의)

  • Ji-Woong, Kim
    • Korean Journal of Psychosomatic Medicine
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    • v.30 no.2
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    • pp.55-65
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    • 2022
  • Although humans exist as Homo Empathicus, human society is actually constantly divided and conflicted between groups. The human empathy response is very sensitive to the justice of others, and depending on the level of others' justice, they may feel empathy or schadenfreude to the suffering of them. However, our empathy to others' suffering are not always fair, and have inherent limitations of ingroup-biased empathy. Depending on whether the suffering other persons belongs to an ingroup or an outgroup, we may feel biased empathy or biased schadenfreude to them without even realizing it. Recent advances in information and communication technology facilitate biased access to ingroup-related SNS or ingroup media, thereby deepening the establishment of a more biased semantic information network related groups. These processes, through interacting with the inherent limitation of empathy, can form a vicious cycle of more biased ingroup empathy and ingroup-related activities, and accelerate divisions and conflicts. This research investigated the properties and limitations of empathy by reviewing studies on the neural mechanism of empathy. By examining the relationship between empathy and justice from a neuroscientific point of view, this research tried to illuminate the modern society of division and conflict in a different dimension from the classical perspective of social science.

3D printed interim immediate denture by using the occlusal plane digital transfer method of the POP BOW system in a patient planning to extract upper and lower residual teeth: a case report (상하악 전악 발거 환자에서 POP BOW 시스템의 교합평면 디지털 전이법을 이용한 3D 프린팅 임시 즉시의치의 수복 증례)

  • Park, Do-Hyun;Bae, Eun-Bin;Jung, In-Hwan;Jeong, Chang-Mo;Yun, Mi-Jung;Huh, Jung-Bo;Lee, So-Hyoun
    • Journal of Dental Rehabilitation and Applied Science
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    • v.38 no.3
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    • pp.178-188
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    • 2022
  • Interim immediate denture is fabricated to minimize the period of edentulousness after removal of the patient's remaining teeth and before delivery of final prosthesis. In the case of using the CAD/CAM system, there is an advantage in that the manufacturing process in the clinic and laboratory can be simplified by overcoming some of the limitations of manufacturing interim immediate dentures in the traditional way. However, there are also disadvantages in that errors occur in the process of transmitting information about the patient's intermaxillary relationship to the digital network of the laboratory, resulting in unstable occlusal relationships or non-esthetic prostheses. To overcome this problem, using the simple and accurate POP BOW system's occlusal plane digital transfer method, it was possible to fabricate an esthetic and functional 3D printed interim immediate denture after removal of the remaining upper and lower anterior teeth.

A research on cyber target importance ranking using PageRank algorithm (PageRank 알고리즘을 활용한 사이버표적 중요성 순위 선정 방안 연구)

  • Kim, Kook-jin;Oh, Seung-hwan;Lee, Dong-hwan;Oh, Haeng-rok;Lee, Jung-sik;Shin, Dong-kyoo
    • Journal of Internet Computing and Services
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    • v.22 no.6
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    • pp.115-127
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    • 2021
  • With the development of science and technology around the world, the realm of cyberspace, following land, sea, air, and space, is also recognized as a battlefield area. Accordingly, it is necessary to design and establish various elements such as definitions, systems, procedures, and plans for not only physical operations in land, sea, air, and space but also cyber operations in cyberspace. In this research, the importance of cyber targets that can be considered when prioritizing the list of cyber targets selected through intermediate target development in the target development and prioritization stage of targeting processing of cyber operations was selected as a factor to be considered. We propose a method to calculate the score for the cyber target and use it as a part of the cyber target prioritization score. Accordingly, in the cyber target prioritization process, the cyber target importance category is set, and the cyber target importance concept and reference item are derived. We propose a TIR (Target Importance Rank) algorithm that synthesizes parameters such as Event Prioritization Framework based on PageRank algorithm for score calculation and synthesis for each derived standard item. And, by constructing the Stuxnet case-based network topology and scenario data, a cyber target importance score is derived with the proposed algorithm, and the cyber target is prioritized to verify the proposed algorithm.

A Study on Application of Improved Tunnel Water-Sealing Grouting Construction Process and the Inverse Analysis Material Selection Method Using the Injection Processing Results (개선된 터널 차수그라우팅 시공 프로세스 적용 및 그 주입시공결과를 이용한 역해석 재료선정방법 연구)

  • Kim, Jin Chun;Yoo, Byung Sun;Kang, Hee Jin;Choi, Gi Sung;Kim, Seok Hyun
    • Journal of Korean Society of Disaster and Security
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    • v.15 no.3
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    • pp.101-113
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    • 2022
  • This study is planned with the aim of developing a systematic construction process based on the scientific and engineering theory of the water-sealing grouting construction applied to the tunnel excavation process during the construction of the downtown underground traffic network, so that the construction quality of the relatively backward domestic tunnel water-sealing grouting construction is improved and continuously maintained no matter who constructs it. The main contents of the improved tunnel water-sealing grouting can be largely examined in the classification of tunnel water-sealing grouting application and the definition of grouting materials, the correlation analysis of groundwater pressure conditions with groundwater inflow, the study of the characteristic factors of bedrock, and the element technologies and injection management techniques required for grouting construction. Looking at the trends in global research, research in the field of theoretical-based science and engineering grouting is actively progressing in Nordic countries (Sweden, Finland, Norway, etc.), Japan, Germany, and the United States. Therefore, in this study, the algorithm is established through theoretical analysis of the elements of tunnel water-sealing grouting construction techniques to provide an integrated solution including a construction process that can effectively construct tunnel water-sealing grouting construction.

Keyword Analysis of Research on Consumption of Children and Adolescents Using Text Mining (텍스트마이닝을 활용한 아동, 청소년 대상 소비관련 연구 키워드 분석)

  • Jin, Hyun-Jeong
    • Journal of Korean Home Economics Education Association
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    • v.33 no.4
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    • pp.1-13
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    • 2021
  • The purpose of this study is to identify trends and potential themes of research on consumption of children and adolescents for 20 years by analyzing keywords. The keywords of 869 studies on consumption of children and adolescents published in journals listed in Korean Citation Index were analyzed using text mining techniques. The most frequent keywords were found in the order of youth, youth consumers, consumer education, conspicuous consumption, consumption behavior, and character. As a result of analyzing the frequency of keywords by dividing into five-year periods, it was confirmed that the frequency of consumer education was significantly higher betwn 2006 and 2010. Research on ethical consumption has been active since 2011, and research has been conducted on various topics instead of without a prominent keyword during the most recent 5-year period. Looking at the keywords based on the TF-IDF, the keywords related to the environment and the Internet were the main keywords between 2001 and 2005. From 2006 to 2010, the TF-IDF values of media use, advertisement education, and Internet items were high. From 2011 to 2015, fair trade, green growth, green consumption, North Korean defector youths, social media, and from 2016 to 2020, text mining, sustainable development education, maker education, and the 2015 revised curriculum appeared as important themes. As a result of topic modeling, eight topics were derived: consumer education, mass media/peer culture, rational consumption, Hallyu/cultural industry, consumer competency, economic education, teaching and learning method, and eco-friendly/ethical consumption. As a result of network analysis, it was found that conspicuous consumption and consumer education are important topics in consumption research of children and adolescents.

An Exploratory Case Study of a Successful Online Start-up Fashion Shopping Store: Focusing on the Entrepreneurial Process of a Soho Shopping Mall (온라인 패션쇼핑몰의 성공적 창업에 대한 탐색적 사례연구: 소호쇼핑몰의 기업가적 과정을 중심으로)

  • Son, Mi Young
    • Science of Emotion and Sensibility
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    • v.25 no.3
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    • pp.91-106
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    • 2022
  • This study targets four Soho fashion shopping malls that are operating successfully in the online fashion market. This study analyzed the entrepreneurship process by dividing it into three stages. The results of the case study are as follows. In the case of Company S, the founder, who had little work experience, started an e-commerce business with a sense of fashion and entrepreneurship. It is a contemporary, casual brand with competitive prices, design power, and diverse product assortment, and the business performance was achieved through data management and analysis and the diversification of distribution channels. In the case of Company B, the founder, who had little work experience, started a manufacturing and e-commerce business by leveraging their SNS network capabilities and entrepreneurial spirit. It is a contemporary fashion brand with product competitiveness of specific items and start-up characteristics, and performance was achieved through the establishment of brand identity and market expansion. Third, Company M and Company C are examples of Soho fashion shopping malls where the founders with more extensive work experience at the time of founding their respective start-ups focused on brand recognition as their core competitiveness. In the case of Company M, the apparel brand was launched with a wealth of experience and design spirit. It is a fashion designer brand that stands out for its sensibility, and the owner has achieved performance through various entrepreneurial activities that broaden the corporate horizon. Company C is a manufacturing and e-commerce brand that was started with design capabilities and an entrepreneurial spirit. It is a luxury fashion brand that focuses on emotional expression, and the outcomes, such as brand recognition and sales, were achieved through active customer management. The results of this study can be used as basic data in education for and research of Soho shopping malls and the prospective founders.

Effectiveness of the Detection of Pulmonary Emphysema using VGGNet with Low-dose Chest Computed Tomography Images (저선량 흉부 CT를 이용한 VGGNet 폐기종 검출 유용성 평가)

  • Kim, Doo-Bin;Park, Young-Joon;Hong, Joo-Wan
    • Journal of the Korean Society of Radiology
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    • v.16 no.4
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    • pp.411-417
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    • 2022
  • This study aimed to learn and evaluate the effectiveness of VGGNet in the detection of pulmonary emphysema using low-dose chest computed tomography images. In total, 8000 images with normal findings and 3189 images showing pulmonary emphysema were used. Furthermore, 60%, 24%, and 16% of the normal and emphysema data were randomly assigned to training, validation, and test datasets, respectively, in model learning. VGG16 and VGG19 were used for learning, and the accuracy, loss, confusion matrix, precision, recall, specificity, and F1-score were evaluated. The accuracy and loss for pulmonary emphysema detection of the low-dose chest CT test dataset were 92.35% and 0.21% for VGG16 and 95.88% and 0.09% for VGG19, respectively. The precision, recall, and specificity were 91.60%, 98.36%, and 77.08% for VGG16 and 96.55%, 97.39%, and 92.72% for VGG19, respectively. The F1-scores were 94.86% and 96.97% for VGG16 and VGG19, respectively. Through the above evaluation index, VGG19 is judged to be more useful in detecting pulmonary emphysema. The findings of this study would be useful as basic data for the research on pulmonary emphysema detection models using VGGNet and artificial neural networks.