• Title/Summary/Keyword: 경계 특성

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Theoretical Study on the Selective Reduction of Chiral [2-(diphenyl hydroxy-methyl)pyrrolidine]-AlH Derivatives and Aromatic Ketone ([2-(diphenyl hydroxy-methyl)pyrrolidine]-AlH 유도체와 방향족 케톤의 선택적 환원에 대한 이론적 연구)

  • Lee, Chul Jae;Kim, Jong-Mi
    • The Journal of the Convergence on Culture Technology
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    • v.7 no.2
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    • pp.389-394
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    • 2021
  • In this work, we study the properties of molecular structure and boundary orbital functions of the DPHMP-AlH and propiophenone and butyrophenone, which are forms of alkoxy-amine-aluminum derivatives. Furthermore, we investigate the effect on the selective reduction of the final products (R), (S)-phenylpropanol and (R), (S)-phenylbutanol by calculating the stereoscopic and thermodynamic parameters of the transition state. Considering the three-dimensional molecular structural stability, the transition status of (S) types DPHMP-AlH and alkylphenone was found to be more stable, resulting in the selective reductions of DPHM-AlH and alkylphenone from this result: (S)-(1)-phenylpropanol and (S)-(1)-phenylbutanol was confirmed that the formation was advantageous.

Reproduction of Flood Inundation in Marine City, Busan During the Typhoon Chaba Invasion Using ADCSWAN and FLOW-3D Models (ADCSWAN과 FLOW-3D 모델을 이용한 태풍 차바 내습 시 부산 마린시티의 침수범람 재현)

  • Choi, Heung-Bae;Um, Ho-Sik;Park, Jong-Jib;Kang, Taeuk
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.26 no.7
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    • pp.881-891
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    • 2020
  • In recent years, large-scale development of coastal areas has caused the loss of many lives and extensive property damage in coastal areas, due to wave overtopping caused by high-wave invasion and strong typhoons. However, coastal inundation studies considering the characteristics of domestic coastal areas are insufficient. This study is a methodology study that aimed to reproduce inundation of surge and wave complex elements by applying the ADCSWAN (ADCIRC+SWAN) and FLOW-3D models. In this study, the boundary data (sea level, wave) of the FLOW-3D model was extracted using the ADCSWAN (ADCIRC+SWAN) model and applied as the input value of the FLOW-3D model and a reproduction was created of the Flooding due to surge and overtopping in Busan Marine City when the typhoon Chaba passed. In addition, the existing overtopping empirical equation and the overtopping calculated by the FLOW-3D model were compared, and for coastal inundation, a qualitative verification was performed using the Inundation Trace Map of Land and Geospatial Informatrix Corporation, and the effectiveness of this study was reviewed.

A Study on the Performative Case of Contemporary Ceramics through Convergence with Performance (퍼포먼스와 융합을 통한 현대 도예의 수행적 사례 연구)

  • Chung, Yong Hyun
    • Journal of the Korea Convergence Society
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    • v.13 no.4
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    • pp.227-232
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    • 2022
  • This thesis studies and analyzes the performative expression and meaning of ceramic performance art in the diversifying contemporary ceramic art. Therefore, after analyzing the ceramic performance works of Miquel Barcelό, Josef Nadj, Kang-hyo Lee, Teri Frame, and J. J. McCracken, I tried to find out the performativity and effectiveness of the performance. As a result of the study, the ceramic performance shows the expandability beyond the expression form and production process shown in general ceramic artworks through physical actions using clay. In addition, the real-time performance of the actor is a process embodiment of creating an event, and the open structure in which the artist and the audience relate to each other enables interpretation and understanding in a different way than before. Convergence attempts with other media imply borderlessness in contemporary ceramics and show the possibility of expanding into new field. This is expected to have a positive impact that breaks the ideological frame of the ceramic arts field, which has strong craft characteristics.

Performance of selective combining according to channel selection decision method of frequency diversity in underwater frequency selective channel (수중 주파수 선택적 채널에서 주파수 다이버시티의 채널 선택 판정법에 따른 선택 합성법의 성능)

  • Lee, Chaehui;Jeong, Hyunsoo;Park, Kyu-Chil;Park, Jihyun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.26 no.3
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    • pp.436-442
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    • 2022
  • In this paper, the performance of the selective combining according to the channel selection decision method of frequency diversity is evaluated in the underwater frequency selective channel. The underwater acoustic channel in the shallow sea has a complex multipath characteristic by combining various environmental factors such as boundary surface reflection and sound wave refraction according to the water temperature layer. In particular, frequency selectivity due to multipath causes energy fluctuation in a communication channel, which reduces SNR (Signal to Noise Ratio) and deteriorates communication performance. In this paper, we applied the frequency diversity technique using multiple channels to secure the communication performance according to the frequency selectivity by multipath. For each channel, 4-FSK (Frequency Shift Keying) and selective combining were applied, the performance was evaluated by applying the maximum value, average value, and majority decision of the signal in order to decide the demodulation channel selection of the selective combining.

A Study on Gamification-based Effective Digital Marketing Plan Targeting at Generation MZ (MZ세대를 겨냥한 게이미피케이션 기반 효과적인 디지털 마케팅 방안 연구)

  • Nang, Yunseo;Kim, Kyujung
    • The Journal of the Korea Contents Association
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    • v.22 no.7
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    • pp.202-215
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    • 2022
  • The purpose of this study is to identify gamification techniques and characteristics of digital marketing based on the main information communication, learning, and play of the current consumer group, and to present effective gamification digital marketing plans for the MZ generation. The summary of the research process is as follows. First, the characteristics and definitions of MZ generation and gamification were described and the concept was clarified. Second, domestic and foreign gamification cases were compared and analyzed. Studies show that we should be wary of gamification digital marketing, which fails to reflect the characteristics of the fun-seeking MZ generation by failing to organically connect the mechanisms and structures of gamification, focusing only on visible elements, such as Point, Badge, and Leaderboard. In addition, customers who lose the fun of obtaining rewards and leave because they feel that the rewards (points, badges, leaderboards) they provide are worthless should be prevented.

Determination of Density of Saturated Sand Considering Particle-fluid Interaction During Earthquake (입자-유체 상호거동을 고려한 지진시 포화 모래지반의 밀도 결정)

  • Kim, Hyun-Uk;Lee, Sei-Hyun;Youn, Jun-Ung
    • Journal of the Korean Geotechnical Society
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    • v.38 no.10
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    • pp.41-48
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    • 2022
  • The mass density of the medium (ρ) used to calculate the maximum shear modulus (Gmax) of the saturated ground based on the shear wave velocity is unclear. Therefore, to determine the mass density, a verification formula and five scenarios were established. Laboratory tests were conducted, and the obtained results were compared. The mass density of the medium was assumed to be saturated (ρsat), wet (ρt), dry (ρdry), and submerged conditions (ρsub), and the Vs ratios of saturated to dry condition were obtained from each case. Assuming the saturated density (ρsat), the Vs ratio was consistent with the value from the resonant column test (RCT) results, and the value from the bender element test results was consistent with the wet density assumption (ρt). Considering the frequency range of earthquakes, it is concluded that applying the saturated density (ρsat) is reasonable as in the RCT results.

Mutual interference suppression of the sinusoidal frequency modulated pulse using SHAPE algorithm (SHAPE 알고리즘을 이용한 사인파 주파수 변조 펄스의 상호간섭 억제)

  • Kim, Guenhwan;Lee, Donghwa
    • Journal of Korea Society of Industrial Information Systems
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    • v.27 no.5
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    • pp.49-59
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    • 2022
  • The SHAPE algorithm has the advantage of being able to shape the pulse spectrum as desired and design it not to distort other characteristics, so it was used in the active sonar pulse design. In this paper, we propose a pulse design using the SHAPE algorithm for a multi-static sonar system to reduce the cross-correlation between frequency-adjacent pulses and prevent the performance degradation of the pulses themselves. The boundary function of the SHAPE algorithm is set to be limited to the pulse bandwidth. As a result of applying the proposed design method to the sinusoidal frequency modulated pulse, the peak cross-correlation level (PCCL), which means the degree of cross-correlation, was reduced by 44.23 dB. Although the PCCL decreased by several tens of dB, no significant change in the ambiguity function was observed, and the integrated sidelobe level (ISL), which means the average value of the side lobe, increased by 11.64 dB.

A Study on the Direction of Christian education in the Age of hyper connectivity Society (초연결성 사회에서의 기독교교육 방향 모색)

  • Chung, Ha Eun
    • Journal of Christian Education in Korea
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    • v.71
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    • pp.371-399
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    • 2022
  • The era we are living in is an era of hyperconnectivity where boundaries and limitations of each field and domain disappear and organically converge and share with each other. Christians living in the age of hyperconnectivity are losing their direction of life due to various divisions and severances, such as holiness and secularity, church and world, soul and body, faith and life, and humans and nature. However, in a hyperconnected society, it is necessary to break free from division and conflict caused by disconnection, and realize the kingdom of God through connection and solidarity between humans, nature, and the world. In order to explore the direction of Christian education for this purpose, this study examined the characteristics of the era of hyperconnectivity and the principle of solidarity, which is the core of hyperconnectivity. The theological meaning of solidarity was examined in terms of humans, nature, and the world, and based on this understanding, the direction of Christian education in the era of hyperconnectivity was sought. It can be summarized as having a religious understanding of human beings of Homoconnectus with a pericoretic mode of existence. Third, education on the kingdom of justice and peace where we can live together in a solidarity relationship can be summarized.

A Study on the Perception of Travel YouTube Title: Focusing on the Group of Generation Z (여행 유튜브 제목에 대한 Z세대의 인식 유형 연구)

  • Choi, Won Joo;Hong, Jang Sun
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.6
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    • pp.175-184
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    • 2022
  • Travel YouTubers who cross the boundary between tradition and novelty communicate by sharing their activities with others through SNS-based media. Media content should not only satisfy individuals, nor should it be too purpose-oriented. YouTube channels should be operated so that users can easily access content naturally, and more diverse methods can be pursued based on usage patterns and satisfaction theory. This study is about the type of perception of Generation Z on travel YouTube titles. As a result of conducting QUANL program analysis on 34 Q samples and 28 P samples from the Q methodological perspective, a total of three types were found. For types with unique characteristics, the first type was named "attention of keywords that draw imagination," the second type was "preferred to stories that stimulate curiosity," and the third type was "image satisfaction reflecting expectations." In addition, considering the characteristics of each type found, the scalability and strategic plan of the activities that Generation Z travel YouTubers want to unfold were presented.

Effect of Overlap Design on the Impact Characteristics of Piecewise Integrated Composite Plates (구간 조합 복합재료 판의 충격 특성에 미치는 겹침부 설계에 관한 연구)

  • Hui-Yun Hwang;Monem Moktadir;Asif Istiak
    • Composites Research
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    • v.36 no.1
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    • pp.25-31
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    • 2023
  • Composite structures have been designed by stacking the laminae with different stacking angles to meet the required mechanical performance. Although the induced stresses on the composite structures under the external loads usually differ depending on the location, we determined the stacking sequence based on the maximum stress, which leads to low efficiency and generally is not the optimum design. Recently, piecewise integrated composites (PICs) were suggested for solving this inefficiency. PICs assume the perfect bonding between adjacent pieces, but this is ideal and hard to accomplish. Therefore, the overlap at the boundary is essential to prevent separation from each other. In this study, we investigated the effect of the overlap design on the impact failure mode of PIC plates. We fabricated the sample composite plates with different overlap designs using the fast curing carbon prepreg and conducted the impact tests according to ASTM D 7136. We found that PICs had different failure modes according to the overlap design, which lead the changes of absorbed impact energies as well as impact load curves.