Highly Efficient Polymer Light-Emitting Diodes Using Graphene Oxide as a Hole Transport Layer

Lee, Bo Ram,Kim, Jung-woo,Kang, Dongwoo,Lee, Dong Wook,Ko, Seo-Jin,Lee, Hyun Jung,Lee, Chang-Lyoul,Kim, Jin Young,Shin, Hyeon Suk,Song, Myoung Hoon American Chemical Society 2012 ACS NANO Vol.6 No.4

<P>We present an investigation of polymer light-emitting diodes (PLEDs) with a solution-processable graphene oxide (GO) interlayer. The GO layer with a wide band gap blocks electron transport from an emissive polymer to an ITO anode while reducing the exciton quenching between the GO and the active layer in place of poly(styrenesulfonate)-doped poly(3,4-ethylenedioxythiophene) (PEDOT:PSS). This GO interlayer maximizes hole–electron recombinations within the emissive layer, finally enhancing device performance and efficiency levels in PLEDs. It was found that the thickness of the GO layer is an important factor in device performance. PLEDs with a 4.3 nm thick GO interlayer are superior to both those with PEDOT:PSS layers as well as those with rGO, showing maximum luminance of 39 000 Cd/m<SUP>2</SUP>, maximum luminous efficiencies of 19.1 Cd/A (at 6.8 V), and maximum power efficiency as high as 11.0 lm/W (at 4.4 V). This indicates that PLEDs with a GO layer show a 220% increase in their luminous efficiency and 280% increase in their power conversion efficiency compared to PLEDs with PEDOT:PSS.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2012/ancac3.2012.6.issue-4/nn300280q/production/images/medium/nn-2012-00280q_0007.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn300280q'>ACS Electronic Supporting Info</A></P>

Identification of cell‐penetrating osteogenic peptide from copine‐7 protein and its delivery system for enhanced bone formation

Lee, Dongwoo,Park, Kwang‐,Sook,Yoon, Gook Jin,Lee, Hyun Jung,Lee, Jue‐,Yeon,Park, Yoon Shin,Park, Joo‐,Cheol,Lee, Gene,Chung, Chong Pyoung,Park, Yoon Jeong Wiley Publishers 2019 JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART A Vol.107 No.11

<P><B>Abstract</B></P><P>Peptide and proteins are recognized as highly selective and therapeutically active biomaterials, as well as relatively safe in clinical application. A calcium phospholipid‐binding protein, copine 7 (CPNE7), has been recently identified to induce hard tissue regeneration, including bone and dentin by internalizing into the cells. However, the clinical application of the full length of CPNE7 has limited due to its large size with short half‐life. Herein, as an alternative to CPNE7, six bioactive synthetic peptides are designed from CPNE7 (CPNE7‐derived peptides, CDP1–CDP6) and investigated their osteogenic potential. Among the CDPs, CDP4 have the highest level of cell‐penetrating activity as well as osteogenic efficiency in dental pulp stem cells (DPSCs). CDP4 increased the expression of osteogenesis‐related genes and proteins, which was comparable to that by BMP‐2. The cell penetration capacity of CDP4 may synergistically induce the osteogenic potential of DPSCs. Moreover, the implantation of the mixture of CDP4 with injectable collagen gel increased bone formation with recovery in the mouse calvarial defect model, comparable to full‐length CPNE7 and even BMP‐2. In conclusion, these results suggest that our synthetic peptide, CDP4, can be applied in combination with biomaterial to provide high osteogenic efficacy in the field of bone tissue engineering.</P>

Environment Adaptive Emergency Evacuation Route GUIDE through Digital Signage Systems

Dongwoo Lee,Daehyun Kim,Junghoon Lee,Seungyoun Lee,Hyunsuk Hwang,Vinayagam Mariappan,Minwoo Lee,Jaesang Cha 국제문화기술진흥원 2017 International Journal of Advanced Culture Technolo Vol.5 No.1

Nowadays, the most of commercial buildings are build-out with complex architecture and decorated with more complicated interiors of buildings so establishing intelligible escape routes becomes an important case of fire or other emergency in a limited time. The commercial buildings are already equipped with multiple exit signs and these exit signs may create confusion and leads the people into different directions under emergency. This can jeopardize the emergency situation into a chaotic state, especially in a complex layout buildings. There are many research focused on implementing different approached to improve the exit sign system with better visual navigating effects, such as the use of laser beams, the combination of audio and video cues, etc. However the digital signage system based emergency exit sign management is one of the best solution to guide people under emergency situations to escape. This research paper, propose an intelligent evacuation route GUIDE that uses the combination centralized Wireless Sensor Networks (WSN) and digital signage for people safety and avoids dangers from emergency conditions. This proposed system applies WSN to detect the environment condition in the building and uses an evacuation algorithm to estimate the safe route to escape using the sensor information and then activates the signage system to display the safe evacuation route instruction GUIDE according to the location the signage system is installed. This paper presented the prototype of the proposed signage system and execution time to find the route with future research directions. The proposed system provides a natural intelligent evacuation route interface for self or remote operation in facility management to efficiently GUIDE people to the safe exit under emergency conditions.

A Study on Touchless Panel based Interactive Contents Service using IrDA Matrix

Lee, Minwoo,Lee, Dongwoo,Kim, Daehyeon,Ann, Myungsuk,Lee, Junghoon,Lee, Seungyoun,Cho, Juphil,Shin, Jaekwon,Cha, Jaesang The Institute of Internet 2015 International Journal of Internet, Broadcasting an Vol.7 No.2

Touch panel is mainly applied to pressure type touch panel but it occur a low recognition rate and error during long-term use. So, it is partly applied to capacitive touch panel to compensate for these problems but it also can occur a same problems via pollutions. Touch technology has developed a various method but it is not used because of high costs and difficult installation process. So, in this paper, we proposed an input method of touchless panel using IrDA matrix. This method is conducted using an IrDA Matrix composed of depth sensor. It is possible to offer a various contents for multi user. The proposed technology need a development of a high sensitivity sensing method and high-speed processing method of position information for Seamless operation control. And, it is required high-precision drive technology. Also, we proposed a Seamless user recognition for interactive contents service through a touchless panel using IrDA matrix.

Design of Low Cost Real-Time Audience Adaptive Digital Signage using Haar Cascade Facial Measures

Dongwoo Lee,Daehyun Kim,Junghoon Lee,Seungyoun Lee,Hyunsuk Hwang,Vinayagam Mariappan,Minwoo Lee,Jaesang Cha 국제문화기술진흥원 2017 International Journal of Advanced Culture Technolo Vol.5 No.1

Digital signage is becoming part of daily life across a wide range of visual advertisements segments market used in stations, hotels, retail stores, hotels, etc. The current digital signage system used in market is generally works on limited user interactivity with static contents. In this paper, a new approach is proposed using computer vision based dynamic audience adaptive cost-effective digital signage system. The proposed design uses the Camera attached Raspberry Pi Open source platform to employ the real-time audience interaction using computer vision algorithms to extract facial features of the audience. The real-time facial features are extracted using Haar Cascade algorithm which are used for audience gender specific rendering of dynamic digital signage content. The audience facial characterization using Haar Cascade is evaluated on the FERET database with 95% accuracy for gender classification. The proposed system, developed and evaluated with male and female audiences in real-life environments camera embedded raspberry pi with good level of accuracy.

Design of Low Cost Real-Time Audience Adaptive Digital Signage using Haar Cascade Facial Measures

Lee, Dongwoo,Kim, Daehyun,Lee, Junghoon,Lee, Seungyoun,Hwang, Hyunsuk,Mariappan, Vinayagam,Lee, Minwoo,Cha, Jaesang The International Promotion Agency of Culture Tech 2017 International Journal of Advanced Culture Technolo Vol.5 No.1

Digital signage is becoming part of daily life across a wide range of visual advertisements segments market used in stations, hotels, retail stores, hotels, etc. The current digital signage system used in market is generally works on limited user interactivity with static contents. In this paper, a new approach is proposed using computer vision based dynamic audience adaptive cost-effective digital signage system. The proposed design uses the Camera attached Raspberry Pi Open source platform to employ the real-time audience interaction using computer vision algorithms to extract facial features of the audience. The real-time facial features are extracted using Haar Cascade algorithm which are used for audience gender specific rendering of dynamic digital signage content. The audience facial characterization using Haar Cascade is evaluated on the FERET database with 95% accuracy for gender classification. The proposed system, developed and evaluated with male and female audiences in real-life environments camera embedded raspberry pi with good level of accuracy.

Environment Adaptive Emergency Evacuation Route GUIDE through Digital Signage Systems

Lee, Dongwoo,Kim, Daehyun,Lee, Junghoon,Lee, Seungyoun,Hwang, Hyunsuk,Mariappan, Vinayagam,Lee, Minwoo,Cha, Jaesang The International Promotion Agency of Culture Tech 2017 International Journal of Advanced Culture Technolo Vol.5 No.1

Nowadays, the most of commercial buildings are build-out with complex architecture and decorated with more complicated interiors of buildings so establishing intelligible escape routes becomes an important case of fire or other emergency in a limited time. The commercial buildings are already equipped with multiple exit signs and these exit signs may create confusion and leads the people into different directions under emergency. This can jeopardize the emergency situation into a chaotic state, especially in a complex layout buildings. There are many research focused on implementing different approached to improve the exit sign system with better visual navigating effects, such as the use of laser beams, the combination of audio and video cues, etc. However the digital signage system based emergency exit sign management is one of the best solution to guide people under emergency situations to escape. This research paper, propose an intelligent evacuation route GUIDE that uses the combination centralized Wireless Sensor Networks (WSN) and digital signage for people safety and avoids dangers from emergency conditions. This proposed system applies WSN to detect the environment condition in the building and uses an evacuation algorithm to estimate the safe route to escape using the sensor information and then activates the signage system to display the safe evacuation route instruction GUIDE according to the location the signage system is installed. This paper presented the prototype of the proposed signage system and execution time to find the route with future research directions. The proposed system provides a natural intelligent evacuation route interface for self or remote operation in facility management to efficiently GUIDE people to the safe exit under emergency conditions.

A Study on Touchless Panel based Interactive Contents Service using IrDA Matrix

Minwoo Lee,Dongwoo Lee,Daehyeon Kim,Myungsuk Ann,Junghoon Lee,Seungyoun Lee,Juphil Cho,Jaekwon Shin,Jaesang Cha 한국인터넷방송통신학회 2015 International Journal of Internet, Broadcasting an Vol.7 No.2

Touch panel is mainly applied to pressure type touch panel but it occur a low recognition rate and error during long-term use. So, it is partly applied to capacitive touch panel to compensate for these problems but it also can occur a same problems via pollutions. Touch technology has developed a various method but it is not used because of high costs and difficult installation process. So, in this paper, we proposed an input method of touchless panel using IrDA matrix. This method is conducted using an IrDA Matrix composed of depth sensor. It is possible to offer a various contents for multi user. The proposed technology need a development of a high sensitivity sensing method and high-speed processing method of position information for Seamless operation control. And, it is required high-precision drive technology. Also, we proposed a Seamless user recognition for interactive contents service through a touchless panel using IrDA matrix.

A study for IoT data quality characteristics

Changsoo Lee,Sunho Kim,Micheal Wolde,Dongwoo Lee,Sangyup Lee,Jinwoo Lee 대한산업공학회 2018 대한산업공학회 춘계학술대회논문집 Vol.2018 No.4

Large amount of data is one of the most drastic character of IoT environment. And there are many types of data including streaming data also in IoT. Considering data quality in IoT environment, we need to identify such characteristics. Identification of data quality characteristics is the basic of data quality improvement. This paper deals with characteristics affecting data quality: plentiful in amount, diversity in structure, distributed in location, continuous in time, uncertain in circumstances, erroneous in connectivity and so on. Comparison of IoT and non-IoT data quality characteristics are mentioned.

A study for IoT data quality characteristics

Changsoo Lee,Sunho Kim,Micheal Wolde,Dongwoo Lee,Sangyup Lee,Jinwoo Lee 한국경영과학회 2018 한국경영과학회 학술대회논문집 Vol.2018 No.04

Large amount of data is one of the most drastic character of IoT environment. And there are many types of data including streaming data also in IoT. Considering data quality in IoT environment, we need to identify such characteristics. Identification of data quality characteristics is the basic of data quality improvement. This paper deals with characteristics affecting data quality: plentiful in amount, diversity in structure, distributed in location, continuous in time, uncertain in circumstances, erroneous in connectivity and so on. Comparison of IoT and non-IoT data quality characteristics are mentioned.