자동조향기반 사고회피시스템 무인 장애물 구현장치 개발

전종화(Jonghwa Jeon),박성정(Seongjeong Park),박현배(Hyunbae Park),오종화(Jonghwa Oh),전재석(Jaeseok Jeon) 한국자동차공학회 2021 한국자동차공학회 학술대회 및 전시회 Vol.2021 No.11

PARAMETER RANGE OF METAMATERIALS

Jonghwa SHIN 한국산업응용수학회 2013 한국산업응용수학회 학술대회 논문집 Vol.8 No.1

Implementation of a Decimal Divider using a Hybrid Method

Jonghwa Choi,Youngdae Kim,Myungyu Kim,Younggap You 대한전자공학회 2007 ITC-CSCC :International Technical Conference on Ci Vol.2007 No.7

This paper proposed an implementation of a hybrid decimal division algorithm to enhance division speed and it’s implementation. The proposed hybrid algorithm employed either non-restoring or restoring technique (algorithm) on each digit to reduce iterative computations based on the relative remainder values with respect to the half of its divisor. The hybrid decimal divider design addressed rapid operations. Dividers were synthesized using a 0.18 ㎛ CMOS standard cell library for performance comparison purposes. For a 16 digit quotient, the number of computations for the proposed hybrid divider is reduced 36.5 % and 29 % less than the conventional restoring and the non-restoring dividers, respectively.

Electrical Spin Injection and Detection in Semiconductors

Jonghwa Eom,Hyun Cheol Koo,Hyunjung Yi,Jae-Beom Ko,Seon-Gu Huh,Joonyeon Chang,Suk-Hee Han 한국자기학회 2006 한국자기학회 학술연구발표회 논문개요집 Vol.- No.-

Study on the Effect of Blade Leading Edge Damage on Wind Turbine Performance and Load Changes

Jonghwa Kim,Bumsuk Kim 한국신재생에너지학회 2021 AFORE Vol.2021 No.10

Multimodal Parametric Fusion for Emotion Recognition

Jonghwa Kim 한국인터넷방송통신학회 2020 Journal of Advanced Smart Convergence Vol.9 No.1

The main objective of this study is to investigate the impact of additional modalities on the performance of emotion recognition using speech, facial expression and physiological measurements. In order to compare different approaches, we designed a feature-based recognition system as a benchmark which carries out linear supervised classification followed by the leave-one-out cross-validation. For the classification of four emotions, it turned out that bimodal fusion in our experiment improves recognition accuracy of unimodal approach, while the performance of trimodal fusion varies strongly depending on the individual. Furthermore, we experienced extremely high disparity between single class recognition rates, while we could not observe a best performing single modality in our experiment. Based on these observations, we developed a novel fusion method, called parametric decision fusion (PDF), which lies in building emotion-specific classifiers and exploits advantage of a parametrized decision process. By using the PDF scheme we achieved 16% improvement in accuracy of subject-dependent recognition and 10% for subject-independent recognition compared to the best unimodal results.

Investigating the Feature Collection for Semantic Segmentation via Single Skip Connection

Jonghwa Yim(임종화),Kyung-Ah Sohn(손경아) 한국정보과학회 2017 정보과학회논문지 Vol.44 No.12

최근 심층 컨볼루션 신경망을 활용한 이미지 분할과 물체 위치감지 연구가 활발히 진행되고 있다. 특히 네트워크의 최상위 단에서 추출한 특징 지도뿐만 아니라, 중간 은닉 층들에서 추출한 특징 지도를 활용하면 더욱 정확한 물체 감지를 수행할 수 있고 이에 대한 연구 또한 활발하게 진행되고 있다. 이에 밝혀진 경험적 특성 중 하나로 중간 은닉 층마다 추출되는 특징 지도는 각기 다른 특성을 가지고 있다는 것이다. 그러나 모델이 깊어질수록 가능한 중간 연결과 이용할 수 있는 중간 층 특징 지도가 많아지는 반면, 어떠한 중간 층 연결이 물체 분할에 더욱 효과적일지에 대한 연구는 미비한 상황이다. 또한 중간층 연결 방식 및 중간층의 특징 지도에 대한 정확한 분석 또한 부족한 상황이다. 따라서 본 연구에서 최신 깊은 신경망에서 중간층 연결의 특성을 파악하고, 어떠한 중간 층 연결이 물체 감지에 최적의 성능을 보이는지, 그리고 중간 층 연결마다 특징은 어떠한지 밝혀내고자 한다. 그리고 이전 방식에 비해 더 깊은 신경망을 활용하는 물체 분할의 방법과 중간 연결의 방향을 제시한다. Since the study of deep convolutional neural network became prevalent, one of the important discoveries is that a feature map from a convolutional network can be extracted before going into the fully connected layer and can be used as a saliency map for object detection. Furthermore, the model can use features from each different layer for accurate object detection: the features from different layers can have different properties. As the model goes deeper, it has many latent skip connections and feature maps to elaborate object detection. Although there are many intermediate layers that we can use for semantic segmentation through skip connection, still the characteristics of each skip connection and the best skip connection for this task are uncertain. Therefore, in this study, we exhaustively research skip connections of state-of-the-art deep convolutional networks and investigate the characteristics of the features from each intermediate layer. In addition, this study would suggest how to use a recent deep neural network model for semantic segmentation and it would therefore become a cornerstone for later studies with the state-of-the-art network models.

Calcium Mobilization through L-type Channels in Hepatic Stellate Cell Is Essential for TGF-b-mediated CTGF

( Jonghwa Kim ),( Sohee Kang ),( Soohyun Park ),( Ju-yeon Cho ),( Won Sohn ),( David A. Brenner ),( Yong-han Paik ) 대한간학회 2016 춘·추계 학술대회 (KASL) Vol.2016 No.1

Aims: In hepatic fibrogenesis hepatic stellate cell (HSC) is a major cell type responsible for producing a major profibrogenic cytokine TGF-b, and connective tissue growth factor (CTGF), a major fibrogenic mediator in several organs. The multi-functional nature of TGF-b signaling in hepatic fibrogenesis is still elusive. At the previous The Liver Week(2015) we reported that Pyk2 is essential for TGF-b-mediated, Smad-independent CTGF induction. Pyk2 is known to be calcium- sensitive, and TGF-b was reported to increase intracellular calcium level. Therefore, we investigated the relation between intracellular calcium levels and pro-fibrogenic TGF-b/Pyk2 axis in hepatic stellate cell. Methods: Immortalized human stellate cell line, LX-2, has been cultured. After TGF-b treatment, expression of CTGF and a-SMA were assessed with RT-PCR and western blot. Pharmacological inhibitor and siRNA-mediated knockdown were used to modulate the activities and expression levels of protein. Intracelllular calcium mobilization was measured with Fura-4/AM. Activation of Pyk2 was addressed in western blot using different phosphorylation site-specific antibodies. Results: CTGF expression was up-regulated within 1hr in TGF-b stimulated LX-2. This up-regulation was greatly suppressed by siRNA-mediated knockdown and pharmacological inhibitor of Pyk2. TGF-b treatment increased phosphorylation of Pyk2 on tyrosine 402, 579/580, and 881. Consistent with the previous reports, TGF-b increased intracellular calcium concentration in Fura-4-preloaded LX-2. CTGF induction by TGF-b was blocked in dose dependent manner by pre-treatment with BAPTA-AM, an intracellular calcium chelator, while A23187, a calcium ionopore, increased CTGF induction even in the absence of TGF-b, suggesting that increase of intracellular calcium level is enough to induce CTGF expression. In addition, A23187 increased phosphorylation of Pyk2, and CTGF induction by A23187 is also greatly reduced by siRNA of Pyk2. Pre-treament of LX-2 with Nifedipine (an L-type calcium channel blocker) suppressed CTGF induction by TGF-b in dose-dependent manner, while FPL64176 (L-type channel activator) increased CTGF expression without TGF-b. The CTGF up-regulations by TGF-b, A23187, and FPL64176 were all suppressed by siRNA-mediated knockdown and pharmacological inhibitors of Pyk2. Conclusions: In hepatic stellate cell, TGF-b increases the intracellular calcium level through L-type calcium channel, leading to downstream Pyk2 signaling for CTGF induction.

Edge-adaptive Demosaicking for Artifact Suppression Along Line Edges

Jonghwa Lee,Taeuk Jeong,Chulhee Lee IEEE 2007 IEEE transactions on consumer electronics Vol.53 No.3

<P>In this paper, we present an edge-adaptive demosaicking method for artifact suppression along line edges. Although various demosaicking methods have been proposed, they still suffer from artifacts along line edges. In order to suppress these undesirable artifacts, the proposed method first determines the pattern of line edges and interpolates missing pixels along the detected direction during initial interpolation. Then, refinement and calibration processes are carried out in series to improve image quality. Experimental results demonstrate that the proposed method produces visually pleasing images and outperforms existing demosaicking methods in terms of the peak signal-to-noise ratio (PSNR) and the mean squared error of S-CIELAB.</P>

Public Procurement for Innovation in Korea

Jonghwa Choi,Kwang Ho Lee,Ahjung Lee 과학기술정책연구원 2015 STI Policy Review Vol.6 No.2

Public procurement for innovation is used as one of the major policy tools to stimulate innovation and promote growth of small and medium-sized enterprises (SMEs) in Korea. However, it is evaluated that this policy has not been so effective in promoting technological innovation among SMEs largely because it heavily depends on price competitiveness of SMEs products and services. In order to draw some policy implications, this study examines the PPI policies of selected countries as comparative references and conducts an empirical analysis on Korean Public Procurement Services (PPS) data for identifying challenges of the current policy in Korea. We conclude that in order to enhance technological innovations of SMEs, PPI policy in Korea should 1) focus more on the potential competitiveness of SMEs, 2) enlarge public demands especially on R&D services, 3) encourage private sector participation in the public procurement market, 4) improve the assessment criteria for public procurement market registration, and 5) restructure the responsible organizations.