• 한국융합학회논문지
• /
• 제11권12호
• /
• pp.15-22
• /
• 2020

본 논문은 채널 강조(Channel Attentin)와 공간 강조(Spatial Attention) 방법을 결합한 딥 러닝 기반의 초해상도 방법을 제안하였다. 초해상도 과정에서 질감, 특징과 같은 주변 픽셀의 변화량이 큰 고주파 성분의 복원이 중요하다. 채널 강조와 공간 강조를 결합한 특징 강조를 이용한 초해상도 방법을 제안하였다. 기존의 CNN(Convolutional Neural Network) 기반의 초해상도 방법은 깊은 네트워크의 학습이 어려우며, 고주파 성분의 강조가 부족하여 윤곽선이 흐려지거나 왜곡이 발생한다. 문제를 해결하기 위해 스킵-커넥션(Skip Connection)을 적용한 채널 강조와 공간 강조를 결합한 강조 블록과 잔차 블록(Residual Block)을 사용하였다. 방법으로 추출한 강조된 특징 맵을 부-픽셀 컨볼루션(Sub-pixel Convolution)을 통해 특징맵을 확장하여 초해상도를 진행하였다. 이를 통해 기존의 SRCNN과 비교하여 약 PSNR는 5%, SSIM은 3% 향상되었으며 VDSR과 비교를 통해 약 PSNR는 2%, SSIM은 1% 향상된 결과를 보였다.

• International Journal of Vascular Biomedical Engineering
• /
• 제1권2호
• /
• pp.36-41
• /
• 2003

Both flow visualizations and computational fluid dynamics were performed to determine hemodynamics in a total cavopulmonary connection (TCPC) model for surgically correcting congenital heart defects. From magnetic resonance images, an anatomically correct glass model was fabricated to visualize steady flow. The total flow rates were 4, 6 and 8L/min and flow rates from SVC and IVC were 40:60. The flow split ratio between LPA and RPA was varied by 70:30, 60:40 and 50:50. A pressure-based finite-volume software was used to solve steady flow dynamics in TCPC models. Results showed that superior vena cava(SVC) and inferior vena cava(IVC) flow merged directly to the intra-atrial conduit, creating two large vortices. Significant swirl motions were observed in the intra-atrial conduit and pulmonary arteries. Flow collision or swirling flow resulted in energy loss in TCPC models. In addition, a large intra-atrial channel or a sharp bend in TCPC geometries could influence on energy losses. Energy conservation was efficient when flow rates in pulmonary branches were balanced. In order to increase energy efficiency in Fontan operations, it is necessary to remove a flow collision in the intra-atrial channel and a sharp bend in the pulmonary bifurcation.

• 비파괴검사학회지
• /
• 제31권3호
• /
• pp.246-259
• /
• 2011

This study presents a structural health monitoring (SHM) method for bolted connections by using multi-channel wireless impedance sensor nodes and multiple PZT-interfaces. To achieve the objective, the following approaches are implemented. Firstly, a PZT-interface is designed to monitor bolt loosening in bolted connection based on variation of electro-mechanical(EM) impedance signatures. Secondly, a wireless impedance sensor node is designed for autonomous, cost-efficient and multi-channel monitoring. For the sensor platform, Imote2 is selected on the basis of its high operating speed, low power requirement and large storage memory. Finally, the performance of the wireless sensor node and the PZT-interfaces is experimentally evaluated for a bolt-connection model Damage monitoring method using root mean square deviation(RMSD) index of EM impedance signatures is utilized to estimate the strength of the bolted joint.

• 한국통신학회논문지
• /
• 제30권9B호
• /
• pp.596-601
• /
• 2005

In this paper it is focused on the relation between CLR(Cell Loss Ratio) and blocking probability in the wireless ATM access transport. Traffic model of wireless ATH access transport is based on the cell scale, burst scale and call connection level. The CLR due to buffer overflow for wireless access node is derived for VBR traffic. The CLR due to transmission errors for wireless channel is derived. Using the CLR for both access node and wireless channel: the CLR of wireless ATM access transport is derived. The relation between CLR and blocking probability is analyzed for VBR traffic to evaluate performance of wireless ATM access transport.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2009년도 춘계학술대회
• /
• pp.105-107
• /
• 2009

본 논문에서는 대형 매장 혹은 임의의 공간과 공간사이에 다른 뮤직콘텐츠를 필요로 할 때 이를 해결해 줄 수 있는 멀티 스트리밍 플랫폼에 대해 연구한다. 사용자의 인터넷 사용을 겸하기 위해 NAT를 구성하고, Multi-Channel Connection을 위한 Application 설계방법과 그에 따른 Multi Stream을 위한 Hardware Path를 구현하는 방법을 제안한다.

• 인터넷정보학회논문지
• /
• 제20권1호
• /
• pp.113-124
• /
• 2019

Recently, Omni Channel Services has been considered the most innovative business strategy. Omni-Channel sees a variety of channels from all channels viewpoints, organically combining each channel to provide a seamless experience for consumers. In other words, Omni-Channel is not simply a systematic integration of channels, but a means of delivering consistent services to consumers in all processes through a strategy to an organic connection. The aim of this study is to provide a comprehensive insight into the decision factors affecting the adoption of Omni-channel. For this purpose, an empirical analysis is conducted on the course of acceptanceof the Omni-channel service based on the Unified Theory of Acceptance and Use of Technology (UTAUT) and Task-technology fit (TTF), an effective model frequently selected to describe the acceptance of service in the introduction phase of new information technology. As a result of the study, it was confirmed that the task characteristics and the technical characteristics had a positive effect on the task-technology fit, and the task-technology fit had a positive effect on the performance expectancy. In addition, task-technology fit, performance expectancy, and social influence have a positive effect on the intention to use the Omni-Channel. This study is intended to deliver an experimental meaning by proposing a strategical measure to understand the behaviorsand uses of consumers in the Omni-channel service environment and increase the customer satisfaction for the system.

• 한국소음진동공학회논문집
• /
• 제27권1호
• /
• pp.94-99
• /
• 2017

Breaking the rigid connection between the two faces of the wall can significantly improve the sound transmission loss of the wall. This is usually achieved by resiliently mounting the gypsum board on one of the two faces of the wall using resilient channel. Resilient channel with less stiffness than that of air cavity could move the resonance frequency of the light-weight wall. So we can get higher sound transmission loss at low frequencies for light-weight wall using resilient channel. It's sound transmission loss is 17 dB higher than that of single stud wall, and 5 dB higher than that of double stud wall.

• 한국항행학회논문지
• /
• 제17권4호
• /
• pp.435-441
• /
• 2013

본 논문에서는 무선 인지망에서 멀티 클래스 인지 사용자의 서비스를 지원하기 위해 신경망 예측기법에 의한 예측 연결수락제어기법을 제안한다. 제안한 기법에서는 주 사용자가 도착하여 스펙트럼 핸드오프를 해야 하는 인지 사용자를 실시간과 비 실시간 사용자로 구분하고, 실시간 인지사용자에게 가드채널(guard channel)을 우선하여 사용하도록 한다. 이를 위해서 신경망 예측기법을 이용하여 주 사용자의 도착을 예측하고, 실시간 인지사용자가 스펙트럼 핸드오프 하는데 필요로 하는 채널의 크기를 예약하여 요구하는 서비스 품질(QoS)를 보장한다. 실시간과 비 실시간 인지사용자 연결을 위한 자원스케줄링 방법은 본 논문의 $C_IA$(cognitive user I complete access)방법을 사용하며, 연결 수락제어는 인지사용자에 대해서만 실시하여 주 사용자에게는 간섭이 없도록 한다. 시뮬레이션을 통하여 제안한 연결 수락제어기법이 실시간 인지사용자가 원하는 서비스 품질을 보장할 수 있음을 보인다.

• 복식
• /
• 제67권1호
• /
• pp.40-55
• /
• 2017

The current new distribution environment provides the consumers to shop at anytime and any places by using mobile appliances. So, the companies which run the offline-store increase the contact point with the consumer by launching not only online-store but also the mobile application (app). Moreover, they are trying to operate the Omni-channel shopping environment. In order for this research to draw the direction of 'the Omni-Channel Strategy', which is about the changed distribution environment of the domestic fashion enterprise, the following steps were performed. First of all, the term related to 'Omni-Channel' is defined. And then, Example of the 'Omni-Channel' strategy and 'O2O' business in the domestic distributior were researched. Lastly, present condition of the 'Omni-Channel' strategy case of the domestic fashion industry was researched. At the result, the online-stores usually have several brands which can not represent their identities. It is suggested that each online-store according to each brand has their own characteristic identity. And The Omni-Channel strategy of the domestic fashion enterprise that is needed the connection point connecting the on-line and off-line. It is able to allure the customer to the off-line-store.

• The Journal of Advanced Prosthodontics
• /
• 제9권4호
• /
• pp.271-277
• /
• 2017

PURPOSE. This in vitro study aimed to evaluate the effect of implant connection design (external vs. internal) on the fit discrepancy and torque loss of zirconia and titanium abutments. MATERIALS AND METHODS. Two regular platform dental implants, one with external connection ($Br{\aa}nemark$, Nobel Biocare AB) and the other with internal connection (Noble Replace, Nobel Biocare AB), were selected. Seven titanium and seven customized zirconia abutments were used for each connection design. Measurements of geometry, marginal discrepancy, and rotational freedom were done using video measuring machine. To measure the torque loss, each abutment was torqued to 35 Ncm and then opened by means of a digital torque wrench. Data were analyzed with two-way ANOVA and t-test at ${\alpha}=0.05$ of significance. RESULTS. There were significant differences in the geometrical measurements and rotational freedom between abutments of two connection groups (P<.001). Also, the results showed significant differences between titanium abutments of internal and external connection implants in terms of rotational freedom (P<.001). Not only customized internal abutments but also customized external abutments did not have the exact geometry of prefabricated abutments (P<.001). However, neither connection type (P=.15) nor abutment material (P=.38) affected torque loss. CONCLUSION. Abutments with internal connection showed less rotational freedom. However, better marginal fit was observed in externally connected abutments. Also, customized abutments with either connection could not duplicate the exact geometry of their corresponding prefabricated abutment. However, neither abutment connection nor material affected torque loss values.