손 재활을 위한 로봇 시스템 기술 동향

민지영,문효정,신화희,이용찬 한국재활복지공학회 2023 재활복지공학회논문지 Vol.17 No.4

본 논문은 손 재활 로봇에 대한 연구 동향과 발전 방향을 이해하기 위해 조사하고 요약하는 것을 목표로한다. 최근 손 재활의 수요가 증가함에 따라 손 재활 로봇에 대한 연구는 활발하게 수행되고 있다. 손 재활은 다른 부위에 비해 높은 자유도와 복잡성을 가지며, 이를 효과적으로 치료하기 위해 다양한 형태의 로봇과 손 재활 방법이 연구되고 있다. 다양한 형태의 손 재활 로봇 분석을 위해 착용 형태, 사용자 의도 파악방식, 구동 방식으로 분류하여 정리하였다. 또, 손 재활 방법의 이해를 위해 제어 알고리즘, 재활 동작, 사용자-로봇 상호작용 내용으로 분류하였다. 결과적으로 손 재활 로봇의 최고 수준과 각 시스템의 성능을 분석하고 생체 데이터의 딥러닝, 재활 시스템에 인공지능 적용 등 향후 연구 방향을 제시하고자 한다. This paper aims to investigate and summarize to understand the research trends and development directions for hand rehabilitation robots. Recently, as the demand for hand rehabilitation increases, research on hand rehabilitation robots is being actively conducted. Hand rehabilitation has a higher degree of freedom and complexity compared to other parts, and various types of robots and hand rehabilitation methods are being studied to treat this effectively. To analyze various types of hand rehabilitation robots, they were categorized and organized into wearing type, user intention identification method, and driving method. In addition, to understand the hand rehabilitation method, it was classified into control algorithm, rehabilitation movement, and user-robot interaction content. As a result, we want to analyze the state-of-the-art of hand rehabilitation robots and the performance of each system and suggest future research directions, such as deep learning of biometric data and application of artificial intelligence to rehabilitation systems.

러·북 정상회담의 주요 이슈와 러시아의 평가

민지영,김경민 대외경제정책연구원 2023 KIEP 세계경제 포커스 Vol.23 No.38

혼합원자가 $Sr_xEu_{1-x}FeO_{3-y}$ ($0.00{\leq}x{\leq}$1.00)계의 비화학량론과 물성 연구

민지영,노권선,여철현,Ji Young Min,Kwon Sun Roh,Chul Hyun Yo 대한화학회 1994 대한화학회지 Vol.38 No.12

$Sr_xEu_{1-x}FeO_{3-y}$ (0.00{\leq}x{\leq}1.00)계의 고용체 시료를 $1200^{\circ}C$와 대기압하에서 합성하였다. X-선 회절분석, 열분석, Mohr염 분석 및 Mossbauer 분광분석을 수행하여 합성된 고용체의 구조들을 규명하고 전기 전도도를 측정하여 물성에 관한 논의를 하였다. X-선 회절 분석 결과 x = 0.00, 0.25 및 1.00인 조성계들은 사방정계이고, x = 0.50과 0.75인 조성계들은 입방정계이다. 입방세포로 환산된 격자부피는 x값이 증가함에 따라 증가한다. Mohr염 적정으로 고용체내의 $Fe^{4+}$이온의 몰비 또는 $\tau$값을 결정하고 전기 중성화 조건에 의해 산소 비화학량 또는 y값을 계산하여 비화학량론적 화학식을 설정한다. Fe 이온의 혼합원자가 상태, 산소 배위상태 및 공유결합성을 Mossbauer 분광분석 결과와 관련하여 논의한다. 전기전도도의 활성화 에너지는 -100 ~ $600^{\circ}C$ 의 온도범위와 대기압하에서 $\tau$값에 의존하였다. 시료의 Mossbauer 스펙트럼과 전기전도도를 비화학량론적 화학조성과 관련시켜 논의 하였다. A series of samples of solid solutions in the $Sr_xEu_{1-x}FeO_{3-y}(0.00{\leq}x{\leq}1.00)$ system has been prepared at $1200^{\circ}C$ under an atmospheric air pressure. The structures of solid solutions are studied by X-ray diffraction, thermal, Mohr salt, and Mossbauer spectroscopic analyses. Their physical properties are also discussed with the electrical conductivities. X-ray diffraction data for the compositions of x = 0.00, 0.25, and 1.00 are assigned to the orthorhombic and the compositions of x = 0.50 and 0.75 to the cubic systems. The lattice volume reduced to cubic cell increases with the x value. The mole ratio of $Fe^{4+}$ iometric chemical formulas of the system are formulated from the x, $\tau$, and y values. The mixed valency state of Fe ions, the oxygen coordination, and covalent bond character are discussed with the Mossbauer spectroscopic data. The activation enegy of the electrical conductivities depends on the $\tau$ value in the temperature range of -$100^{\circ}C$ to $600\circC$ under the air pressure. The Mossbauer spectrum and electrical conductivity of the solid solutions are discussed with nonstoichiometric chemical compositions.

비전센서 및 딥러닝을 이용한 항만구조물 방충설비 세분화 시스템 개발

민지영,유병준,김종혁,전해민 한국구조물진단유지관리공학회 2022 한국구조물진단유지관리공학회 논문집 Vol.26 No.2

As port structures are exposed to various extreme external loads such as wind (typhoons), sea waves, or collision with ships; it is important to evaluate the structural safety periodically. To monitor the port structure, especially the rubber fender, a fender segmentation system using a vision sensor and deep learning method has been proposed in this study. For fender segmentation, a new deep learning network that improves the encoder-decoder framework with the receptive field block convolution module inspired by the eccentric function of the human visual system into the DenseNet format has been proposed. In order to train the network, various fender images such as BP, V, cell, cylindrical, and tire-types have been collected, and the images are augmented by applying four augmentation methods such as elastic distortion, horizontal flip, color jitter, and affine transforms. The proposed algorithm has been trained and verified with the collected various types of fender images, and the performance results showed that the system precisely segmented in real time with high IoU rate (84%) and F1 score (90%) in comparison with the conventional segmentation model, VGG16 with U-net. The trained network has been applied to the real images taken at one port in Republic of Korea, and found that the fenders are segmented with high accuracy even with a small dataset. 매립지 위에 건설되는 항만시설물은 바람(태풍), 파랑, 선박과의 충돌 등 극한 외부 하중에 노출되기 때문에 구조물의 안전성 및 사용성을 주기적으로 평가하는 것이 중요하다. 본 논문에서는 항만 계류시설에 설치된 방충설비의 유지관리를 위하여 비전 및 딥러닝 기반의 방충설비 세분화(segmentation) 시스템을 개발하였다. 방충설비 세분화를 위하여 인코더-디코더 형식과 인간 시각체계의 편심 기능에서 영감을 얻은 수용 영역 블록(Receptive field block) 기반의 합성곱 모듈을 DenseNet 형식으로 개선하는 딥러닝 네트워크를 제안하였다. 네트워크 훈련을 위해 BP형, V형, 원통형, 타이어형 등 다양한 형태의 방충설비 영상을 수집하였으며, 탄성 변형, 좌우 반전, 색상 변환 및 기하학적 변환을 통해 영상을 증강시킨 다음 제안한 딥러닝 네트워크를 학습하였다. 기존의 세분화 모델인 VGG16-Unet과 비교하여 제안한 모델의 세분화 성능을 검증하였으며, 그 결과 본 시스템이 IoU 84%, 조화평균 90% 이상으로 정밀하게 실시간으로 세분화할 수 있음을 확인하였다. 제안한 방충설비 세분화 시스템의 현장적용 가능성을 검증하기 위하여 국내 항만 시설물에서 촬영된 영상을 기반으로 학습을 수행하였으며, 그 결과 기존 세분화 모델과 비교하였을 때 우수한 성능을 보이며 정밀하게 방충설비를 감지하는 것을 확인하였다.

Factors affecting determination of the optimal ketamine dose for pediatric sedation

민지영,이정림,김현일,변효진 대한응급의학회 2019 Clinical and Experimental Emergency Medicine Vol.6 No.2

Objective Children are sedated before undergoing diagnostic imaging tests in emergency medi­cine or pediatric sedation anesthesia units. The aim of this study was to identify variables poten­tially affecting the dose of ketamine required for induction of sedation in pediatric patients un­dergoing diagnostic imaging.Methods This retrospective study included children aged 0 to 18 years who underwent sedation with ketamine for computed tomography or magnetic resonance imaging in the pediatric seda­tion anesthesia unit of a tertiary medical center between January 2011 and August 2016. The children’s hemodynamic status and depth of sedation were monitored during the examination. We recorded data on demographics, categories of imaging tests, ketamine doses administered, adverse events, respiratory interventions, and duration of sedation. Data for patients who expe­rienced adverse events were excluded.Results Sixty-six patients were included in the final analysis. Univariate linear regression analysis revealed that patient age, height, and body surface area (BSA) affected the sedative dose of ket­amine administered. These three variables showed multicollinearity in multivariate linear regres­sion analysis and were analyzed in three separate models. The model with the highest adjusted R-squared value suggested the following equation for determination of the dose of ketamine re­quired to induce sedation: ketamine dose (mg)=-1.62+0.7×age (months)+36.36×BSA (m2).Conclusion Variables such as age and BSA should be considered when estimating the dose of ketamine required for induction of sedation in pediatric patients.

대학의 자기 주도적 융합교육과정 동향

민지영 한국문화융합학회 2023 문화와 융합 Vol.45 No.1

This study examined self-directed interdisciplinary curriculum trends in higher education by delving into the self-directed interdisciplinary curricula (SDIC) of Korean universities, compared to those of U.S. universities. Data sources included SDIC information from the individualized studies program websites and hyperlinked documents. The analysis centered on (1) whether a student should include interdisciplinary independent study and experiential learning courses and (2) whether a student was given support in curriculum design and course study. Results revealed that U.S. and Korean universities enacted SDIC under different names to make the traditional curriculum diverse and flexible. The former required students to develop course plans, including interdisciplinary independent study and experiential learning courses. The latter encouraged students to design course plans to improve their multidisciplinary expertise and skills. Both SDIC were oriented toward the shared object: to foster individuals equipped with creativity and interdisciplinary competencies to meet the needs of society and industry. U.S. universities provided diverse aids to students who planned to take the SDIC. Korean universities gradually secured professionals to help students design and complete the SDIC. Based on the results, I suggested management systems of SDIC in higher education.

스마트폰 학습 앱을 사용한 어휘 학습이 초등학생의 영어 어휘 능력과 태도에 미치는 영향

민지영,이은주 한국외국어교육학회 2018 Foreign languages education Vol.25 No.1

With the advent of mobile technology, teaching and learning have been more effective with the help of smartphone education applications. This study investigates the effects of vocabulary learning using the smartphone education applications on Korean elementary school learners’ English vocabulary learning and attitudes. A total of fifty-seven elementary school students in the 5th grade participated in the study and were randomly divided into an experimental and a control group. The results of the study manifested that both the experimental and control group showed an increase in the comprehension and production score from pre- to post-tests. The effects of the long-term vocabulary learning, however, were not found to be statistically significant. The average score in the delayed test for both groups slightly increased, which indicated that the treatment was beneficial for learners’ long-term memory enhancement. In the affective domain, interests and confidence ratings were significant for the upper-level experimental and lower-level control group. The results of the survey questionnaire showed that the vocabulary learning using direct examples and pictures for both groups was helpful to improve learners’ lexical competence.

Comparison of the Diagnostic Accuracies of 1.5T and 3T Stress Myocardial Perfusion Cardiovascular Magnetic Resonance for Detecting Significant Coronary Artery Disease

민지영,고성민,송인영,이정근,황흥곤,신제균 대한영상의학회 2018 Korean Journal of Radiology Vol.19 No.6

Objective: To compare the diagnostic performance of cardiovascular magnetic resonance (CMR) myocardial perfusion at 1.5- and 3-tesla (T) for detecting significant coronary artery disease (CAD), with invasive coronary angiography (ICA) as the reference method. Materials and Methods: We prospectively enrolled 281 patients (age 62.4 ± 8.3 years, 193 men) with suspected or known CAD who had undergone 1.5T or 3T CMR and ICA. Two independent radiologists interpreted perfusion defects. With ICA as the reference standard, the diagnostic performance of 1.5T and 3T CMR for identifying significant CAD (≥ 50% diameter reduction of the left main and ≥ 70% diameter reduction of other epicardial arteries) was determined. Results: No differences were observed in baseline characteristics or prevalence of CAD and old myocardial infarction (MI) using 1.5T (n = 135) or 3T (n = 146) systems. Sensitivity, specificity, positive and negative predictive values, and area under the receiver operating characteristic curve (AUC) for detecting significant CAD were similar between the 1.5T (84%, 64%, 74%, 76%, and 0.75 per patient and 68%, 83%, 66%, 84%, and 0.76 per vessel) and 3T (80%, 71%, 71%, 80%, and 0.76 per patient and 75%, 86%, 64%, 91%, and 0.81 per vessel) systems. In patients with multi-vessel CAD without old MI, the sensitivity, specificity, and AUC with 3T were greater than those with 1.5T on a per-vessel basis (71% vs. 36%, 92% vs. 69%, and 0.82 vs. 0.53, respectively). Conclusion: 3T CMR has similar diagnostic performance to 1.5T CMR in detecting significant CAD, except for higher diagnostic performance in patients with multi-vessel CAD without old MI.

장주기 지진에 대한 철근콘크리트 건물의 비선형요구내력 스펙트럼의 제안

민지영,이복기,이강석,최윤철 국제차세대융합기술학회 2021 차세대융합기술학회논문지 Vol.5 No.6

내진설계용 스펙트럼은 건물주기 약 1초 미만의 단주기 건물 증폭형이다. 결과적으로 장주기를 가지는 고 층 건축물은 지진에 대해서 안전군이라고 인식되고 있다. 하지만 최근 장주기 지진의 발생빈도가 늘어나고 있으 며, 장주기 지진에 대한 고층 건축물의 내진설계법, 내진성능 평가법 등을 포함한 이에 대한 대책이 시급한 실정 이다. 하지만, 장주기 지진에 대한 연구는 극히 제한적으로 진행이 되고 있으며, 극소수의 연구자들에 의해서 수행 되고 있는 것이 현재의 실정이다. 본 연구에서는 고층 철근콘크리트 (이하, RC) 건물의 내진설계 및 내진성능 평 가에 기초적인 자료로서 활용하기 위한 장주기 지진에 대한 RC 건물의 비선형요구내력스펙트럼을 제안하였다. 비 선형요구내력스펙트럼은 전단파괴형 RC 건물을 상정한 Origin-Oriented 모델 및 휨파괴형 RC 건물을 상정한 Degrading Trilinear 모델을 각각 이용하여 SDOF 비선형동적해석에 의해서 제안하였다. The major characteristics of seismic design spectrum is a amplification type for buildings having short period (T) of less than approximately T=0.1. As a result, high-rise buildings with long periods have been widely recognized as safety groups against earthquakes. Recently because the frequency of long period earthquakes has been increased, recently, countermeasures for such earthquakes including the seismic design method and seismic performance evaluation method of high-rise buildings are urgently needed. However, studies on long period earthquakes are being conducted limitedly, and the current situation is that they are being conducted by very few researchers. In this study, the nonlinear required spectrum of RC buildings for long-period earthquakes was proposed to be used as basic data for seismic design and seismic performance evaluation of high-rise RC buildings. The nonlinear required spectrum was proposed by using SDOF nonlinear dynamic analysis using the Origin-Originated model assuming the shear-controlled RC building and the Degrading Trilinear model assuming the flexure-controlled RC building, respectively.

Development of a low-cost multifunctional wireless impedance sensor node

민지영,Seunghee Park,윤정방,Byunghun Song 국제구조공학회 2010 Smart Structures and Systems, An International Jou Vol.6 No.6

In this paper, a low cost, low power but multifunctional wireless sensor node is presented for the impedance-based SHM using piezoelectric sensors. Firstly, a miniaturized impedance measuring chip device is utilized for low cost and low power structural excitation/sensing. Then, structural damage detection/sensor self-diagnosis algorithms are embedded on the on-board microcontroller. This sensor node uses the power harvested from the solar energy to measure and analyze the impedance data. Simultaneously it monitors temperature on the structure near the piezoelectric sensor and battery power consumption. The wireless sensor node is based on the TinyOS platform for operation, and users can take MATLAB interface for the control of the sensor node through serial communication. In order to validate the performance of this multifunctional wireless impedance sensor node, a series of experimental studies have been carried out for detecting loose bolts and crack damages on lab-scale steel structural members as well as on real steel bridge and building structures. It has been found that the proposed sensor nodes can be effectively used for local wireless health monitoring of structural components and for constructing a low-cost and multifunctional SHM system as place and forget wireless sensors.