Jeong-Tak Ryu

Dr. Jeong-Tak Ryu

Department of Electronic Engineering, Daegu University, Gyeongsan 38453, Republic of Korea

Research Focus & Metrics

Academic Career Length

31Years (1996-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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30 September 1998 in Surface Science
Verified
Journal Article
Closed access
OKO. Kubo
O. Kubo
ASA.A. Saranin
A.A. Saranin
AZA.V. Zotov
A.V. Zotov
JRJeong-Tak Ryu
Jeong-Tak Ryu
HTH. Tani
H. Tani
KOK. Oura
K. Oura

15 November 1999 in Physical Review B
Verified
Journal Article
Closed access
PDF file
ASA. A. Saranin
A. A. Saranin
AZA. V. Zotov
A. V. Zotov
VLV. G. Lifshits
V. G. Lifshits
JRJeong-Tak Ryu
Jeong-Tak Ryu
OKO. Kubo
O. Kubo
KOK. Oura
K. Oura
The advantages of scanning tunneling microscopy for the determination of the composition of the submonolayer metal/silicon interfaces has been demonstrated using Si(100)4×3-In and Si(111)4×1-In as sample reconstructions. It has been found that the Si(100)4×3-In unit cell is built of 7 In atoms and 6 Si atoms, while the Si(111)4×1-In unit cell contains 3 In atoms and 2 Si atoms in addition to the top Si(111) bilayer. The obtained quantitative information provides the ground for discussion of the plausible atomic arrangement of these reconstructions.

1 January 1999 in Surface Science
Verified
Journal Article
Closed access
TFTakashi Fuse
Takashi Fuse
TFToshiaki Fujino
Toshiaki Fujino
JRJeong-Tak Ryu
Jeong-Tak Ryu
MKMitsuhiro Katayama
Mitsuhiro Katayama
KOKenjiro Oura
Kenjiro Oura

1 June 1999 in Surface Science
Verified
Journal Article
Closed access
ASA.A. Saranin
A.A. Saranin
AZA.V. Zotov
A.V. Zotov
VLV.G. Lifshits
V.G. Lifshits
JRJeong-Tak Ryu
Jeong-Tak Ryu
OKO. Kubo
O. Kubo
KOK. Oura
K. Oura

15 August 1998 in Physical Review B
Verified
Journal Article
Closed access
PDF file
ASA. A. Saranin
A. A. Saranin
AZA. V. Zotov
A. V. Zotov
SRSergei V. Ryzhkov
Sergei V. Ryzhkov
DTD. A. Tsukanov
D. A. Tsukanov
VLV. G. Lifshits
V. G. Lifshits
KOK. Oura
K. Oura
Using scanning tunneling microscopy (STM), we have studied the formation and structure of the Si(100)2×3−Na surface phase. It has been found that both the formation process and atomic arrangement of the Si(100)2×3−Na surface differ substantially from those known for 2×3 reconstructions induced by other alkali and alkaline earth metals, since the Si(100)2×3-Na phase is the only one in which the top Si layer undergoes a substantial reordering. The Si-atom density in the Si(100)2×3−Na surface phase has been determined to be 1/3 ML. A structural model of the Si(100)2×3-Na reconstruction has been proposed, and its registry to STM images has been discussed.

23 July 2019 in Applied Sciences
Verified
Journal Article
Open access
PDF file
DKDonghwoon Kwon
Donghwoon Kwon
RMRitesh Malaiya
Ritesh Malaiya
GYGeumchae Yoon
Geumchae Yoon
JRJeong-Tak Ryu
Jeong-Tak Ryu
SPSu-Young Pi
Su-Young Pi
One of the recent news headlines is that a pedestrian was killed by an autonomous vehicle because safety features in this vehicle did not detect an object on a road correctly. Due to this accident, some global automobile companies announced plans to postpone development of an autonomous vehicle. Furthermore, there is no doubt about the importance of safety features for autonomous vehicles. For this reason, our research goal is the development of a very safe and lightweight camera-based blind spot detection system, which can be applied to future autonomous vehicles. The blind spot detection system was implemented in open source software. Approximately 2000 vehicle images and 9000 non-vehicle images were adopted for training the Fully Connected Network (FCN) model. Other data processing concepts such as the Histogram of Oriented Gradients (HOG), heat map, and thresholding were also employed. We achieved 99.43% training accuracy and 98.99% testing accuracy of the FCN model, respectively. Source codes with respect to all the methodologies were then deployed to an off-the-shelf embedded board for actual testing on a road. Actual testing was conducted with consideration of various factors, and we confirmed 93.75% average detection accuracy with three false positives.