휴먼형 로봇 손의 사물 조작 수행을 이용한 인간 행동 복제 강화학습 정책 최적화 방법 성능 평가

박나현 ( Na Hyeon Park ),오지헌 ( Ji Heon Oh ),류가현 ( Ga Hyun Ryu ),( Edwin Valarezo Añazco ),( Patricio Rivera Lopez ),원다슬 ( Da Seul Won ),정진균 ( Jin Gyun Jeong ),장윤정 ( Yun Jung Chang ),김태성 ( Tae-seong Kim ) 한국정보처리학회 2020 한국정보처리학회 학술대회논문집 Vol.27 No.2

로봇이 사람과 같이 다양하고 복잡한 사물 조작을 하기 위해서 휴먼형 로봇손의 사물 파지 작업이 필수적이다. 자유도 (Degree of Freedom, DoF)가 높은 휴먼형(anthropomorphic) 로봇손을 학습시키기 위하여 사람 데모(human demonstration)가 결합된 강화학습 최적화 방법이 제안되었다. 본 연구에서는 강화학습 최적화 방법에 사람 데모가 결합된 Demonstration Augmented Natural Policy Gradient (DA-NPG)와 NPG 의 성능 비교를 통하여 행동 복제의 효율성을 확인하고, DA-NPG, DA-Trust Region Policy Optimization (DA-TRPO), DA-Proximal Policy Optimization (DA-PPO)의 최적화 방법의 성능 평가를 위하여 6 종의 물체에 대한 휴먼형 로봇손의 사물 조작 작업을 수행한다. 그 결과, DA-NPG 와 NPG를 비교한 결과를 통해 휴먼형 로봇손의 사물 조작 강화학습에 행동 복제가 효율적임을 증명하였다. 또한, DA-NPG 는 DA-TRPO 와 유사한 성능을 보이면서 모든 물체에 대한 사물 파지에 성공하여 가장 안정적이었다. 반면, DA-TRPO 와 DA-PPO 는 사물 조작에 실패한 물체가 존재하여 불안정한 성능을 보였다. 본 연구에서 제안하는 방법은 향후 실제 휴먼형 로봇에 적용하여 휴먼형 로봇 손의 사물조작 지능 개발에 유용할 것으로 전망된다.

Whole-genome resequencing analysis of 20 Micro-pigs

Da‑Hye Son,Nam‑Hyun Hwang,Won‑Hyong Chung,Ha‑Seung Seong,Hyungbum Lim,Eun‑Seok Cho,Jung‑Woo Choi,Kyung‑Soo Kang,Yong‑Min Kim 한국유전학회 2020 Genes & Genomics Vol.42 No.3

Background Miniature pigs have been increasingly used as mammalian model animals for biomedical research because of their similarity to human beings in terms of their metabolic features and proportional organ sizes. However, despite their importance, there is a severe lack of genome-wide studies on miniature pigs. Objective In this study, we performed whole-genome sequencing analysis of 20 Micro-pigs obtained from Medi Kinetics to elucidate their genomic characteristics. Results Approximately 595 gigabase pairs (Gb) of sequence reads were generated to be mapped to the swine reference genome assembly (Sus scrofa 10.2); on average, the sequence reads covered 99.15% of the reference genome at an average of 9.6-fold coverage. We detected a total of 19,518,548 SNPs, of which 8.7% were found to be novel. With further annotation of all of the SNPs, we retrieved 144,507 nonsynonymous SNPs (nsSNPs); of these, 5968 were found in all 20 individuals used in this study. SIFT prediction for these SNPs identified that 812 nsSNPs in 402 genes were deleterious. Among these 402 genes, we identified some genes that could potentially affect traits of interest in Micro-pigs, such as RHEB and FRAS1. Furthermore, we performed runs of homozygosity analysis to locate potential selection signatures in the genome, detecting several loci that might be involved in phenotypic characteristics in Micro-pigs, such as MSTN, GDF5, and GDF11. Conclusion In this study, we identified numerous nsSNPs that could be used as candidate genetic markers with involvement in traits of interest. Furthermore, we detected putative selection footprints that might be associated with recent selection applied to miniature pigs.

디메틸포름아미드 노출 근로자의 요중 N-메틸포름아미드 분석시 GC-NPD와 GC-FID 방법간 비교

정다운,김현욱 가톨릭대학산업의학센타 산업의학연구소 1999 韓國의 産業醫學 Vol.38 No.1

This purpose of the this study was to compare the results of two analytical techniques, GC-NPD and GC-FID, of quantifying urinary NMF from 70 DMF exposed workers in synthetic resins, leather, and dye manufacturing industries. In addition, the relationship between conecntrations of airborne DMF and urinary NMF was investigated using samples collected from 12 workers. Airborne DMF was sampled using both charcoal and silicagel tubes. All urine specimens were collected both prior-to and at end-of workshifts. The results were as follows: 1. The detection limits of urinary NMF by GC-FID and GC-NPD were 0.043㎎/l and 0.009㎎/l, respectively. The recovery rates were 96.9% for the GC-NPD and 90.2% for the GC-FID methods. 2. Desorption efficiencies of DMF on Charcoal tubes were very poor with 32.96%, while those on silicagel tubes were marginally acceptable with 85.70%. 3. A statistically significant relationship between concentrations of airborne DMF and urinary NMF from 12 workers determined by GC-NPD (r=0.74) and by GC-FID (r=0.67) was observed. 4. Geometric mean concentrations of urinary NMF of the end-of-shift urines from 70 workers were 15.84㎎/g creatinine by GC-NPD and were 9.88㎎/g creatinine by GC-FID, respectivery. For the prior-to-shift samples, they were 6.05 ㎎/g creatinine by GC-NPD and 0.92㎎/g creatinine by GC-FID. These results of this study suggest that for collecting airborne DMF in the workplace, silicagel tubes should be utilized. For quantifying urinary NMF concentrations as a biological marker of DMF exposed workes, urine should be collected at the end-of-shift. Urinary NMF should be analyzed by GC-NPD because of its lower of detection and better precision than that of GC-FID.

행동 복제 강화학습 및 딥러닝 사물 부분 검출 기술에 기반한 사람형 로봇손의 사물 조작

오지헌 ( Ji Heon Oh ),류가현 ( Ga Hyun Ryu ),박나현 ( Na Hyeon Park ),( Edwin Valarezo Añazco ),( Patricio Rivera Lopez ),원다슬 ( Da Seul Won ),정진균 ( Jin Gyun Jeong ),장윤정 ( Yun Jung Chang ),김태성 ( Tae-seong Kim ) 한국정보처리학회 2020 한국정보처리학회 학술대회논문집 Vol.27 No.2

최근 사람형(Anthropomorphic)로봇손의 사물조작 지능을 개발하기 위하여 행동복제(Behavior Cloning) Deep Reinforcement Learning(DRL) 연구가 진행중이다. 자유도(Degree of Freedom, DOF)가 높은 사람형 로봇손의 학습 문제점을 개선하기 위하여, 행동 복제를 통한 Human Demonstration Augmented(DA)강화 학습을 통하여 사람처럼 사물을 조작하는 지능을 학습시킬 수 있다. 그러나 사물 조작에 있어, 의미 있는 파지를 위해서는 사물의 특정 부위를 인식하고 파지하는 방법이 필수적이다. 본 연구에서는 딥러닝 YOLO 기술을 적용하여 사물의 특정 부위를 인식하고, DA-DRL 을 적용하여, 사물의 특정 부분을 파지하는 딥러닝 학습 기술을 제안하고, 2 종 사물(망치 및 칼)의 손잡이 부분을 인식하고 파지하여 검증한다. 본 연구에서 제안하는 학습방법은 사람과 상호작용하거나 도구를 용도에 맞게 사용해야하는 분야에서 유용할 것이다.

Changes in Antigenicity of Gliadin from Strong Dough by Physical Treatments and Secondary Structure of Gliadin

Da-Hyun JEONG,Koth-Bong-Woo-Ri KIM,Min-Ji KIM,Dong-Hyun KIM,Chan SUNWOO,Seul-A JUNG,Hyun-Jee KIM,Hee-Ye JUNG,Jung-Su CHOI,Seong-Won KIM,Dong-Hyun AHN 한국생물공학회 2012 한국생물공학회 학술대회 Vol.2012 No.4

Design of a Work Process and Implementation of a Prototype for the Development of an Automation Tool for Android Application Vulnerability Inspection

Da-Woon Leem,Hyun-Ju Jung,Moon-Sung Hwang,Jung-Ah Shim,Hyun-Jung Kwon 보안공학연구지원센터 2016 International Journal of Software Engineering and Vol.10 No.3

As a variety of services are provided through mobile devices, there have been increasing security threats to mobile platforms and applications. Many mobile application security check methodologies are proposed to deal with such threats, but it is not clear exactly how the security vulnerabilities are inspected, and there is no correct methodology for such. One way to increase the execution rate of vulnerability check is to develop an automation tool that simplifies the process. Therefore, in this study, a work process of Android application vulnerability inspection was designed and a prototype of the automation tool for vulnerability inspection was implemented. Furthermore, the effectiveness of the implemented prototype was assessed through an actual application using the prototype.

Association among epicardial fat, HR recovery, circadian BP variability in patients with hypertension

( Hyun-Joon Park ),( Da-Jung Kim ),( Kyoung-Im Cho ),( Jin-Wook Lee ),( Sun-Min Kim ),( Hyun-Su Kim ),( Jung Ho Heo ) 대한내과학회 2015 대한내과학회 추계학술대회 Vol.2015 No.1

Background: Epicardial fat tissue has unique endocrine and paracrine functions that affect the cardiac autonomic system. Heart rate recovery (HRR) is a simple non-invasive measurement that assesses autonomic nervous system dysfunction. We aimed to investigate the association between epicardial fat thickness (EFT) and HRR in patients with hypertension according to circadian blood pressure (BP) variation. Methods: A total of 358 consecutive patients who underwent both 24-hour ambulatory BP monitoring (ABPM) and a treadmill test were enrolled. Echocardiographic EFT and HRR, defined as peak heart rate minus heart rate after a 1-minute recovery time, were measured. Patients were classified according to the ABPM; 147 patients with hypertension with a dipping pattern at night (dippers), 140 patients with hypertension with a non-dipping pattern at night (non-dippers) and 71 normotensive controls. Results: EFT was significantly higher in hypertensive patients, especially in the non-dipper group, compared to the controls (non-dippers, 7.5 ± 2.9 mm; dippers, 6.6 ± 1.6 mm; controls, 5.5 ± 2.1 mm; p<0.001). HRR was significantly lower in both hypertensive groups as compared to the control group and was the lowest in the non-dipper group (non-dipper, 26.6 ± 18.6; dipper, 29.5 ± 21.5; control, 71.4 ± 19.8; p<0.001). EFT was significantly correlated with age, body mass index, 24-hour mean systolic BP and 24 hours mean BP variability, whereas exercise duration, metabolic equivalents (METs) and HRR were inversely correlated with EFT. Furthermore, EFT>6.7 mm was associated with a blunted HRR with 76% sensitivity and 61% specificity (ROC area under curve: 0.71, 95% confidence interval, CI=0.65-0.76, p<0.001). In a multivariate analysis, EFT (odds ratio, OR =3.53, 95% CI=1.20-10.37, p=0.022) and 24-hour mean BP variability (OR=1.09, 95% CI=1.03-1.16, p=0.005) were independent predictors of a blunted HRR defined as HRR ≤12 beats (n=63) in patients with hypertension. Conclusions: EFT and circadian BP variability were independent predictors of blunted HRR in patients with hypertension, which suggests a link between epicardial fat and autonomic dysregulation in hypertension.

Peptide Nucleic Acid Probe-Based Analysis as a New Detection Method for Clarithromycin Resistance in Helicobacter pylori

( Da Hyun Jung ),( Jie-hyun Kim ),( Su Jin Jeong ),( Soon Young Park ),( Il-mo Kang ),( Kyoung Hwa Lee ),( Young Goo Song ) 대한소화기학회 2018 Gut and Liver Vol.12 No.6

Background/Aims: Helicobacter pylori eradication rates are decreasing because of increases in clarithromycin resistance. Thus, finding an easy and accurate method of detecting clarithromycin resistance is important. Methods: We evaluated 70 H. pylori isolates from Korean patients. Duallabeled peptide nucleic acid (PNA) probes were designed to detect resistance associated with point mutations in 23S ribosomal ribonucleic acid gene domain V (A2142G, A2143G, and T2182C). Data were analyzed by probe-based fluorescence melting curve analysis based on probe-target dissociation temperatures and compared with Sanger sequencing. Results: Among 70 H. pylori isolates, 0, 16, and 58 isolates contained A2142G, A2143G, and T2182C mutations, respectively. PNA probe-based analysis exhibited 100.0% positive predictive values for A2142G and A2143G and a 98.3% positive predictive value for T2182C. PNA probe-based analysis results correlated with 98.6% of Sanger sequencing results (κ-value=0.990; standard error, 0.010). Conclusions: H. pylori clarithromycin resistance can be easily and accurately assessed by dual-labeled PNA probe-based melting curve analysis if probes are used based on the appropriate resistance-related mutations. This method is fast, simple, accurate, and adaptable for clinical samples. It may help clinicians choose a precise eradication regimen. (Gut Liver 2018;12:641-647)

HER2 Regulates Cancer Stem Cell Activities via the Wnt Signaling Pathway in Gastric Cancer Cells

Jung, Da Hyun,Bae, Yoo Jin,Kim, Jie-Hyun,Shin, You Keun,Jeung, Hei-Cheul S. Karger AG 2019 Oncology Vol.97 No.5

<P><B><I>Introduction:</I></B> Human epidermal growth factor 2 (<I>HER2</I>) gene overexpression in breast carcinoma cell lines has been shown to drive mammary carcinogenesis and tumor growth and invasion through its effects on mammary stem cells. <B><I>Objective:</I></B> Therefore, we investigated the mechanism by which HER2 regulates cancer stem cell (CSC) activity in gastric cancer cells. <B><I>Methods:</I></B><I>HER2</I> was transfected into MKN28 gastric cancer cells, and its role in regulating CSC activity was determined by characterizing the HER2-overexpressing cells. <B><I>Results:</I></B> The sphere formation assay revealed that the sphere sizes and frequency of sphere formation were significantly greater for the HER2-overexpressing cells than for the MKN28 control cells. The CSC markers Oct-4 and BMI1 were more highly expressed in the HER2-overexpressing cells, as were the EMT markers. This was accompanied by a significant enhancement in cellular invasion of the Matrigel and migration. The E-cadherin level was significantly downregulated, and the mesenchymal marker Snail upregulated, in the <I>HER2</I>-transfected cells. HER2 overexpression activated the well-characterized CSC-associated Wnt/β-catenin signaling pathway, as shown by the luciferase assay. After treatment of these cells with the Wnt signal inhibitor PRI-724, the BMI1 and Oct-4 levels were decreased for 24 h and Snail was also downregulated. Immunofluorescence staining revealed the significant restoration of E-cadherin levels in the <I>HER2</I>-transfected cells after PRI-724 treatment. <B><I>Conclusions:</I></B> These results established a role for HER2 in regulating gastric CSC activity, with Wnt/β-catenin signaling being mediated via a HER2-dependent pathway. In summary, HER2-overexpressing gastric cancer cells exhibited increased stemness and invasiveness and were regulated by Wnt/β-catenin signaling.</P>

Clinicopathologic Analysis of Proton Pump Inhibitor-Responsive Esophageal Eosinophilia in Korean Patients

( Da Hyun Jung ),( Gak Won Yun ),( Yoo Jin Lee ),( Yunju Jo ),( Hyojin Park ) 대한소화기기능성질환·운동학회 2016 Gut and Liver Vol.10 No.1

Background/Aims: Proton pump inhibitor-responsive esophageal eosinophilia (PPI-REE) is a newly recognized form of eosinophilic esophagitis (EoE) that responds to PPI therapy. It remains unclear whether PPI-REE represents a subphenotype of gastroesophageal reflux disease, a subphenotype of EoE, or its own distinct entity. The aim was to evaluate the clinicopathologic features of PPI-REE. Methods: Six patients were diagnosed with PPI-REE based on symptoms, endoscopic abnormalities, esophageal eosinophilia with ≥15 eosinophils/high-power field, and a response to PPI treatment. Symptoms and endoscopic and pathological findings were evaluated. Results: The median follow-up duration was 12 months. Presenting symptoms included dysphagia, heartburn, chest pain, foreign body sensation, acid reflux, and sore throat. All patients had typical endoscopic findings of EoE such as esophageal rings, linear furrows, nodularity, and whitish plaques. Three patients had a concomitant allergic disorder, and one had reflux esophagitis. Four patients exhibited elevated serum IgE, and five had positive skin prick tests. All patients experienced symptomatic resolution within 4 weeks and histologic resolution within 8 weeks after starting PPI therapy. There was no symptomatic recurrence. Conclusions: PPI therapy induced rapid resolution of symptoms and eosinophil counts in patients with PPI-REE. Large-scale studies with long-term follow-up are warranted. (Gut Liver 2016;10:37-41)