• 한국환경과학회지
• /
• 제11권9호
• /
• pp.881-895
• /
• 2002

Sediments and river waters form the channel of Hwasun-cheon were studied in sedimentological size and geochemical analyses of metallic elements for the purposes of identification of depositional environments and geochemical characteristics. The sizes of sediments are assigned to pebble to coarse sand in mean size and polymodal in distribution. And the sediments are poorly to very poorly sorted and positively skewed. According to the grain size distributions of the sediments, the Hwasun-cheon belongs to gravel-bed river on the basis of the grain size distribution of the sediments. The behaviors of metallic elements in the sediments mainly depend on not grain size distribution but the geology connected with geomorphological reliefs near the stream. Contamination indices(CI) of Zn, Cu and Pb are 2.83 to 6.96 with average 4.31 in the sediments. Hwasun-cheon is assigned to general stream type in accordance with water quality of physical factors and chemical characteristics by Piper's diagram. Though meaningful values of BOD, T-N, T-P were locally depicted near Masan-ri, Hwasun-eup and Jiseok-cheon areas, artificial metal concentration do not represent in the most area of the stream. Sediments and river water are considered that the relatively more or less high metallic contents in the stream are originated from coal mine and urban area.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제9권11호
• /
• pp.4483-4501
• /
• 2015

In this paper, we investigate a security transmission scheme at the physical layer for cooperative wireless relay networks in the presence of a passive eavesdropper. While the security scheme has been previously investigated with perfect channel state information(CSI) in the presence of a passive eavesdropper, this paper focuses on researching the robust cooperative relay beamforming mechanism for wireless relay networks which makes use of artificial noise (AN) to confuse the eavesdropper and increase its uncertainty about the source message. The transmit power used for AN is maximized to degrade the signal-to-interference-plus-noise-ratio (SINR) level at the eavesdropper, while satisfying the individual power constraint of each relay node and worst-case SINR constraint at the desired receiver under a bounded spherical region for the norm of the CSI error vector from the relays to the destination. Cooperative beamforming weight vector in the security scheme can be obtained by using S-Procedure and rank relaxation techniques. The benefit of the proposed scheme is showed in simulation results.

• The Journal of Asian Finance, Economics and Business
• /
• 제7권11호
• /
• pp.439-447
• /
• 2020

The dynamics of communications powered by the Internet, specifically from the increased use of social media, has led marketers to find creative channels to engage with the customers. One of the recent channels, "branded entertainment", is becoming familiar as an advertising strategy in which the content presented is a marketing tool for the advertising of certain brands. The current study examined the case of a branded-entertainment channel and the mechanism of the advertising instrument that leads to purchase intention. The specific purpose of this research is to investigate whether there is evidence of the role of narrative transportation and the fantasy proneness leading towards purchase of the brand advertised. To arrive at the conclusion, the study using web series sponsored by an artificial sweetener brand and employs a quantitative survey to question the audience. The findings contribute toward the understanding of how consumers respond to branded entertainment via video-sharing platforms. It is indicated that the stories presented in the web series can stimulate the audience to fantasize. Thus, the advertising message conveyed through narrative persuasion can form a favorable attitude toward the brand, which leads to intention to purchase. Practical elements are identified along with limitations and future research suggestions.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2010년도 학술발표회
• /
• pp.1044-1048
• /
• 2010

해수를 이용한 세계최초의 해수수로인 송도 신도시 중앙공원 해수수로는 서해안에서 집수된 해수를 $5{\mu}m$의 공극 크기를 가지는 해수처리시설 (STF, seawater treatment facility)에 의해 여과된 뒤 2곳의 해수공급 지점에서 해수수로로 공급된다. 여과된 해수는 수로로 155L/sec의 유량으로 1.8km를 흐른 뒤 서해로 방류된다. 이러한 인공 해수수로에서는 흐름정체에 따른 수질 문제와 영양염에 의한 적조를 유발하는 조류 성장이 문제가 된다. 따라서 본 연구에서는 3차원 수치모형을 이용한 인공 해수수로내의 흐름특성 모의와 수질 모니터링의 통한 조류 생성 특성 및 장소를 비교하여 그 상관성을 분석하고자 한다. 수치모의 실험은 3차원 수치모형인 FLOW-3D를 이용하였으며, 격자망 형태는 직사각형 직각 격자가 사용되었다. 현장 모니터링을 통하여 획득한 수질 데이터와 비교 분석을 통하여 해수수로 내 해수 흐름 특성변화(유속, 와도 등)와 조류생성에 미치는 영향을 비교 분석하였다. 해수 수로내의 평균 유속은 0.01m/s 이었으며, 수로의 형상에 따라서 정체수역이 발생하였다. 이러한 정체수역은 현장 모니터링을 통하여 예측된 조류 발생 지역과 일치하였다. 이러한 흐름 특성과 조류생성과의 상관성 규명을 통하여 인공수로의 물순환 시스템 설계시 조류 생성을 억제할 수 있는 최적 관리를 위한 설계의 기초 자료를 제공할 수 있을 것으로 판단된다.

• 대한전기학회논문지:시스템및제어부문D
• /
• 제53권5호
• /
• pp.374-379
• /
• 2004

This paper proposes an algorithm for human sensibility evaluation using 4-channel EEG signals of the prefrontal and the parietal lobes. The algorithm uses an artificial neural network and the multiple templates. The linear prediction coefficients are used as the feature parameters of human sensibility. Comfortableness for chairs and temperature/humidity are evaluated. Many conventional researches have emphasized that a wave of left prefrontal lobe is activated in case of positive sensibility and that of right prefrontal lobe is activated in case of negative sensibility. So the power ratio of a wave is obtained from FFT computation and the results are compared. The results of the comfortableness evaluation for temperature and humidity showed that the outputs of the proposed algorithm coincided with corresponding sensibilities depending on the task of the temperature and the humidity. The . conventional method using a wave is hardly related with comfortableness. And it is also observed that the uncomfortable state due to the high temperature and humidity can be easily changed to the comfortable state by small drop of the temperature and the humidity. It seems to be good results to get 66.7％ of evaluation performance in spite of using EEG and the subject independent approach.

• 한국항해항만학회:학술대회논문집
• /
• 한국항해항만학회 2005년도 추계학술대회 논문집
• /
• pp.141-146
• /
• 2005

본 연구에서는 최근 유체역학 유동장 해석분야에서 각광을 받고 있는 PIV 해석기술을 이용하여 소파블럭과 인공어초 주위의 유동을 실험적으로 분석하였다. 실험에 사용된 소파블럭은 현재 현장에서 널리 채택, 운용되는 삼각뿔 tetrapod를 이용하였고 인공어초로는 원통형인 흄관어초 모형을 이용하였다. 유동장 촬영은 소형 회류수조와 아르곤 레이저, 고속 카메라 등을 이용하였다. 최종적으로 영상정보를 이용하여 PIV 해석을 실시, 실험 대상 물체 주위의 경계층(Boundary layer)영역, 박리 현상 등의 유동 특성을 조사하였다.

• 물과 미래
• /
• 제29권4호
• /
• pp.161-176
• /
• 1996

기존 하천유지유량 결정 방법을 문헌 조사와 항목별 조사 방법 등을 통해 검토하고, 검토 결과를 바탕으로 산정 가능한 항목과 방법에 따라 하천유지유량 결정 방법의 개발 방향을 결정하였다. 이에 따라 하천의 정상적인 기능 유지에 필요한 주요 항목별 필요유량 결정 방법, 구간 및 대표지점에 대한 하천유지유량과 하천관리유량의 결정 방법을 개발하였다. 고려한 항목은 주로 갈수량, 수질 보전, 어류 서식처의 복원 및 보전, 하천 경관, 수상 이용 등이고, 이와 같은 하천의 자연 및 인위적 기능을 유지하는데 필요한 하천 유지유량의 결정방법은 효율적인 하천관리에 필요한 방법을 제공할 수 있을 것이다.

• 패션비즈니스
• /
• 제25권4호
• /
• pp.79-91
• /
• 2021

Currently, chatbot, a conversational platform based on artificial intelligence, is drawing attention as a new marketing channel. This study attempted to verify the effect of the anthropomorphism, message type, and media self-efficacy level on purchase intention. The experimental design of this study was a 2 (anthropomorphism level of shopping chatbot: low vs. high) × 2 (message type: factual vs. evaluative) × 2 (media self-efficacy: low vs. high) three-way mixed analysis of variance (ANOVA). This study conducted a survey by the convenience sampling method of 402 women in their 20s and 30s living in Seoul and the Gyeonggi area who were aware of chatbot services. For the final analysis, 388 questionnaires were used. Data were analyzed with the SPSS 23 program and three-way ANOVA. Simple main effects analysis was conducted. The results of this study were as follows. First, there were statistically significant differences in purchase intention according to anthropomorphism level, message type, and media self-efficacy. Second, message type and media self-efficacy showed statistically significant interaction effects on purchase intention. Lastly, anthropomorphism and the media self-efficacy level and the message type of the shopping chatbots showed significant three-way interaction effects on purchase intention.

• 디지털산업정보학회논문지
• /
• 제14권4호
• /
• pp.69-77
• /
• 2018

The malignant melanoma accounts for about 1 to 3% of the total malignant tumor in the West, especially in the US, it is a disease that causes more than 9,000 deaths each year. Generally, skin lesions are difficult to detect the features through photography. In this paper, we propose a computer-aided diagnosis algorithm based on deep learning for classification of malignant melanoma and benign skin tumor in RGB channel skin images. The proposed deep learning model configures the tumor lesion segmentation model and a classification model of malignant melanoma. First, U-Net was used to segment a skin lesion area in the dermoscopic image. We could implement algorithms to classify malignant melanoma and benign tumor using skin lesion image and results of expert's labeling in ResNet. The U-Net model obtained a dice similarity coefficient of 83.45% compared with results of expert's labeling. The classification accuracy of malignant melanoma obtained the 83.06%. As the result, it is expected that the proposed artificial intelligence algorithm will utilize as a computer-aided diagnosis algorithm and help to detect malignant melanoma at an early stage.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제15권5호
• /
• pp.1929-1943
• /
• 2021

Millimeter wave (mmWave) communication based on the wide bandwidth of >28 GHz is one of the key technologies for cellular-connected unmanned aerial vehicles (UAVs). The selection of mmWave beams in such cellular-connected UAVs is challenging and critical, especially when downlink transmissions toward aerial user equipment (UE) suffer from poor signal-to-interference-plus-noise ratio (SINR) more often than their terrestrial counterparts. This study proposed a coordinated mmWave beam selection scheme using fingerprint for cellular-connected UAV. The scheme comprises fingerprint database configuration and coordinated beam selection. In the fingerprint database configuration, the best beam index from the serving cell and interference beam indexes from neighboring cells are stored. In the coordinated beam selection, the best and interference beams are determined using the fingerprint database information instead of performing an exhaustive search, and the coordinated beam transmission improves the SINR for aerial UEs. System-level simulations assess the UAV effect based on the third-generation partnership project-new radio mmWave and UAV channel models. Simulation results show that the proposed scheme can reduce the overhead of exhaustive search and improve the SINR and spectral efficiency.