Effect of Electrochemical Oxidation-Reduction Cycles on Surface Structures and Electrocatalytic Oxygen Reduction Activity of Au Electrodes

Lim, Taejung,Kim, Jongwon Korean Chemical Society 2016 대한화학회지 Vol.60 No.5

Oxidation-reduction cycling (ORC) procedures are widely used for cleaning nanoparticle surfaces when investigating their electrocatalytic activities. In this work, the effect of ORC on the surface structures and electrocatalytic oxygen reduction activity of Au electrodes is analyzed. Different structural changes and variations in electrocatalysis are observed depending on the initial structure of the Au electrodes, such as flat bulk, nanoporous, nanoplate, or dendritic Au. In particular, dendritic Au structures lost their sharp-edge morphology during the ORC process, resulting in a significant decrease in its electrocatalytic oxygen reduction activity. The results shown in this paper provide an insight into the pretreatment of nanoparticle-based electrodes during investigation of their electrocatalytic activities.

Enhancing the Performance of Organic Dye-Sensitized Solar Cells via a Slight Structure Modification

Lim, Kimin,Kim, Chulwoo,Song, Juman,Yu, Taejung,Lim, Woocherl,Song, Kihyung,Wang, Peng,Zu, Ningning,Ko, Jaejung American Chemical Society 2011 The Journal of Physical Chemistry Part C Vol.115 No.45

<P>A novel organic sensitizer <B>JK-225</B> incorporating a planar indeno[1,2-<I>b</I>]thiophene bridging group was synthesized and compared to its prototype sensitizer <B>JK-2</B>. <B>JK-225</B> affords a short circuit photocurrent of 13.84 mA cm<SUP>–2</SUP>, an open circuit voltage of 790 mV, and a fill factor of 0.75, corresponding to an overall conversion efficiency of 8.2% under standard AM 1.5 sunlight, which is much higher than that of 6.9% in <B>JK-2</B>.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpccck/2011/jpccck.2011.115.issue-45/jp2070776/production/images/medium/jp-2011-070776_0009.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/jp2070776'>ACS Electronic Supporting Info</A></P>

Electrocatalysis of Selective Chlorine Evolution Reaction: Fundamental Understanding and Catalyst Design

Taejung Lim,Jinjong Kim,Sang Hoon Joo The Korean Electrochemical Society 2023 Journal of electrochemical science and technology Vol.14 No.2

The electrochemical chlorine evolution reaction (CER) is an important electrochemical reaction and has been widely used in chlor-alkali electrolysis, on-site generation of ClO^-, and Cl₂-mediated electrosynthesis. Although precious metal-based mixed metal oxides (MMOs) have been used as CER catalysts for more than half a century, they intrinsically suffer from a selectivity problem between the CER and parasitic oxygen evolution reaction (OER). Hence, the design of selective CER electrocatalysts is critically important. In this review, we provide an overview of the fundamental issues related to the electrocatalysis of the CER and design strategies for selective CER electrocatalysts. We present experimental and theoretical methods for assessing the active sites of MMO catalysts and the origin of the scaling relationship between the CER and the OER. We discuss kinetic analysis methods to understand the kinetics and mechanisms of CER. Next, we summarize the design strategies for new CER electrocatalysts that can enhance the reactivity of MMO-based catalysts and overcome their scaling relationship, which include the doping of MMO catalysts with foreign metals and the development of non-precious metal-based catalysts and atomically dispersed metal catalysts.

Developing Design Strategies of E-Learning Interfaces for Supporting Learners` Emotion Regulation

( Cheolil Lim ),( Taejung Park ),( Jungeun Park ),( Wonjoon Hong ) 한국교육공학회 2014 한국교육공학회 학술대회발표자료집 Vol.2014 No.2

In a face-to-face classroom environment, it is possible for a teacher to monitor learners`` emotions and help them manage their emotions for continuous engagement in learning. However, online classes without the touch of a teacher and peers make learners feel more isolated, alienated, lonely, anxious, bored and frustrated (Jarvela, Hurme & Jarvenoja, 2011; Quinn, 2006; Wotnitza & Volet, 2005; Zembylas, Theodorou, & Pavlakis, 2008). Moreover, learners experience more negative emotions in an e-Learning environment than they do in off-line learning environment (Kekkonen-Moneta & Moneta, 2007). A growing number of previous studies have indicated that emotions felt during online learning can enhance or inhibit learning and performance. Nevertheless, the importance of online learners`` emotional experiences has not been well recognized in the research literature (MacFadden, et al., 2005). These emotions experienced in learning situations are called academic emotions. However, academic emotions have been ignored or deemphasized rather than technical and cognitive aspects for more interactive e-Learning environments in instructional design and technology. Based on the importance of emotions in e-Learning environment, emotional elements are required to be considered in designing interface where learners interact with learning content and among teachers and peers. In order for an e-learning to be successful, its interface should be designed and developed to help learners to overcome their negative academic emotions, such as frustration, anger, anxiety, fear and boredom. In learning environments, emotions are critical factors for independent and self-regulated learning as well as cognition, behavior, and motivation (Ben-Eliyahu & Linnenbrink-Garcia, 2012; Efklides, 2011; Pekrun et al., 2002). Hence, this study intended to develop design strategies of e-Learning interface for learners to regulate their academic emotions in learning situations. This study consists of a stage of strategy development by reviewing relevant prior studies, and other stage of strategy validation through in-depth expert interviews and prototype development and evaluation based on Design and Development Research methodology. The final design strategies of e-Learning interface for supporting learners`` academic emotion regulation are composed of 1) Planning, 2) Distraction, 3) Venting, and 4) Social Support. Prototype applying developed four design strategies with twelve detailed guidelines was designed and developed by redesigning an extant interface of an E-Learning site delivering MOOCs-type content. Further research is needed to conduct empirical studies of the impact of developed design strategies and their detailed guidelines on various learning outcomes and emotional responses of e-Learners.

소형 무인기를 이용한 1:1,000 지도제작 가능성 분석: 무인기 기종 및 처리 SW별 비교

김태정(Taejung Kim),임평채(Pyung-Chae Lim),손종환(Jonghwan Son),서정훈(Junghoon Seo) 대한공간정보학회 2019 한국공간정보학회 학술대회 Vol.2019 No.5

Developing Design Principles of Emotional Interface for Self-Regulated Learning in an E-Learning Environment

Cheolil Lim,Taejung Park,Wonjoon Hong,Jungeun Park 한국교육공학회 2013 한국교육공학회 학술대회발표자료집 Vol.2013 No.1

미래학교 공간 구축 및 개선을 위한 핵심 설계요소에 대한 탐색적 연구

임철일 ( Cheolil Lim ),박태정 ( Taejung Park ),한형종 ( Hyeongjong Han ),김근재 ( Keunjae Kim ),권혜성 ( Hyeseong Kwon ),이지연 ( Jiyeon Lee ) 한국교육공학회 2019 교육공학연구 Vol.35 No.S

미래사회 변화에 효과적으로 대응하기 위한 학교 공간 구축의 중요성이 강조되고 있다. 특히, 미래사회가 요구하는 역량의 효과적 향상이 이루어지기 위해서는 거시적인 측면에서 학교공간 및 시설의 구축과 개선이 이루어져야 한다. 미래 교육 환경으로서 학교 공간의 중요성에도 불구하고 이에 대한 종합적인 검토와 체계적인 접근은 미흡하다. 본 연구에서는 미래학교의 보다 최적화된 설계를 위해 고려해야 할 핵심 설계요소를 탐색하는 데 그 목적을 지닌다. 이를 위해 선행 연구 검토, 현장 사례 분석을 통해 고려해야 할 핵심 설계요소를 도출하였다. 이에 대해 미래학교 설계에 대해 전문성을 지닌 대학교수, 연구(위)원 및 장학관, 교사 포함 총 스물여덟 명을 대상으로 전문가 검토를 실시하여 연구 결과에 대한 수정 및 보완이 이루어졌다 연구 결과, 미래 지향적 학교 공간 구축 및 개선을 위한 ‘교수·학습 및 테크놀로지’, ‘정서적 지원’, ‘커뮤니티 생태계’, ‘통합 안전망’ 총 네 개의 구성요소와 열한 개의 핵심 설계요소를 도출하였다. 교수·학습 및 테크놀로지 측면에서 ‘맞춤형 교수·학습 활동 지원’, ‘테크놀로지 활용수업 지원’ 등을 고려해야 하며 학습자의 정서적 지원을 위해서 ‘정서적 편안함 제공’, ‘정서적 즐거움 제공’을 제공해야 한다. 커뮤니티 생태계가 조성되기 위해서는 ‘지역 사회와의 다양한 연계’, ‘사용 주체별 공간 및 시간의 구획화’를 고려할 필요가 있으며 통합 안전망을 구축하기 위해서는 ‘인적 안전망의 체계화’와 ‘물리적 안전망의 스마트화’를 실현해야 한다. The purpose of this study is to explore design elements in the construction of a school space suitable for the future. The importance of constructing school space has been emphasized to effectively respond to future social changes. In particular, it is necessary to build the school space in order to improve future core competencies. Despite the significance of school spaces as a learning environment for future education, there is insufficient research in a comprehensive analysis and the investigation of various stakeholder responses. Using a literature review, cases analysis, components and design elements were derived. Also, the responses of twenty-eight experts including professors, researchers, and teachers were examined to revise the design elements. As a result, the four components were as follows: learning and technology, emotional support, community ecosystem, and integrative safety net. The major design elements of teaching·learning and technology are as follows: ‘supporting customized teaching and learning activities’, and ‘implementing technology-enhanced learning’. To support learner’s feelings, ‘offering affective comfort’ and ‘offering affective pleasure’ should be considered. For the community ecosystem, ‘various links with local communities’ and ‘division of space and time by users’ are included. Systematizing human safety net and making physical safety net smart are necessary for the integrative safety net.

자기조절학습자로서의 암 환자를 위한 치료 여정에 적응적인 온라인 지원 시스템 설계전략 개발

임철일 ( Cheolil Lim ),김성욱 ( Sungwook Kim ),박태정 ( Taejung Park ),윤영호 ( Youngho Yun ) 한국교육정보미디어학회(구 한국교육정보방송학회) 2017 교육정보미디어연구 Vol.23 No.2

본 연구의 목적은 암 환자가 치료 여정에서 겪게 되는 포괄적인 건강위기를 고려하여 자기조절학습자로서의 암 환자가 스스로 자신의 건강상태와 치료과정을 점검하며 필요한 건강정보를 학습하고 수행하는 자기조절학습 능력을 신장하기 위한 온라인 지원 시스템의 설계전략을 개발하는 것이다. 이 목적을 달성하기 위하여 보건의료분야와 교육공학분야의 문헌분석을 통해 암 환자가 겪게 되는 다양한 위기와 치료 여정, 그들의 삶의 질을 향상시키는 주요 요인과 중재 방법을 확인하였으며 효과적인 온라인 지원 시스템의 구조와 기능, 지원도구의 가능성을 탐색하였다. 연구 결과, 암 환자가 겪게 되는 자기평가, 현실수용, 변화준비, 의사결정, 계획, 환경조성, 실행, 피드백 및 유지의 8개의 치료 여정과 총 24개의 세부 단계에 따라 환자의 자기조절학습을 지원하기 위한 온라인 시스템의 설계전략이 개발되었다. 또한 환자의 자기조절학습을 지원하는 온라인 시스템에서 환자에게 제공되어야 할 건강정보의 종류 및 시스템의 기능 등을 도출하였다. 개발된 설계전략을 통해 암 환자가 현재의 건강상태와 바람직한 건강상태간의 차이를 인지하고 둘 사이의 간격을 좁히기 위한 계획을 세워 수행하며 자신의 상태를 지속적으로 평가하는 자기조절행위를 다차원적으로 지원하고자 하였다. 본 연구는 자기조절학습자로서의 암 환자가 자신의 치료과정을 스스로 극복해나갈 수 있도록 지원하는 온라인 지원 시스템설계에 관한 탐색적 연구로서 보건의료 분야에서의 교육공학 이론과 실천의 지평이 확장되기를 기대한다. The aim of this study was to develop design strategies for online support systems that enable cancer patients as self-regulated learners to improve self-regulated learning abilities for acquiring health information and monitoring their own health condition and treatment process, taking into account the comprehensive healthcare crises experienced by them. To achieve the goal, literature review of the healthcare and educational technology fields have identified the various health crises, treatment routes, and the major factors and intervention methods that improve the quality of life for cancer patients. We explored the structure of online support systems, the possibility of the support tool, and then derived design strategies of online support systems to help cancer patients for self-regulated learning skills during their treatment journey. As a result of the research, we developed design strategies of an online support system to help cancer patients self-regulate their learning based on eight their therapeutic journey of self-evaluation, reality acceptance, preparation for change, decision making, planning, creating environments, implementation, and feedback and maintenance and twenty-four detailed procedures. In addition, we derived the types of health information to be provided to the patients and the functions of the system in the online support system. Through design strategies, we sought to multi-dimensionally support cancer patients` self-regulated learning behaviors in perceiving the gaps between the current health status and the desired health status and performing a continuous assessment of the patient`s condition by setting the plans to make up the gaps. This study was an exploratory study to expand the scope of theory and practice of educational technology in health care fields on the design of an online support system that supports cancer patients as self-regulated learners to overcome their treatment process by themselves.

암환자의 긍정성 증진을 위한 블렌디드 건강코칭 교육프로그램 프로토타입 개발 및 적용

임철일(Cheolil Lim),박태정(Taejung Park),김성욱(Sungwook Kim),윤영호(Youngho Yun) 한국IT서비스학회 2019 한국IT서비스학회지 Vol.18 No.5

This study aimed to develop and pilot-test educational program prototypes of training health coaches to help cancer patients overcome crises and create positive growth. For this purpose, the educational contents and methods of the blended learning program prototypes were derived through learner needs and literature analysis. The prototypes, which consist of introducing of health management and health information and understanding and practice of basic coaching and health coaching, were developed to integrate with four sessions of face-to-face, off-line classes, training practices through 12 tele-classes, and use of online learning system. The prototypes were conducted and pilot-tested by a total of 35 students selected through the document screening and the interview. After participating in the blended learning program, learners expressed greater overall satisfaction with each session program (average score = 4.36, with 5 being most satisfied), satisfaction with learning contents (average score=4.42) satisfaction with course preparation (average score = 4.26) and satisfaction with lecture materials (average score = 4.19). The results of this study show that a systematic and integrative approach for designing a blended learning program can be useful for various educational needs in health and medical fields. In the future, empirical studies are expected to see how these curricula are actually implemented and assess whether the intended learning outcomes are achieved.

자기조절학습을 위한 감성조절 지원 이러닝 인터페이스 설계전략 개발

임철일 ( Cheolil Lim ),박태정 ( Taejung Park ),박정은 ( Jungeun Park ) 한국교육정보미디어학회(구 한국교육정보방송학회) 2015 교육정보미디어연구 Vol.21 No.3

성공적인 이러닝을 촉진하기 위해서는 학습자들이 좌절감, 두려움, 지루함, 혼동감 등의 부정 감성을 극복하여 긍정적 감성 상태에서 자기조절학습을 지속할 수 있도록 설계할 필요가 있다. 이에 본연구는 이러닝 환경에서 학습자가 자기조절적으로 학습을 진행할 수 있는 감성상태를 유발 및 유지하도록 도와줄 수 있는 감성조절 지원 인터페이스에 대한 설계전략을 마련하고자 하였다. 이를 위해 문헌고찰을 통해 초기 감성조절 지원 인터페이스 설계전략을 도출한 다음, 전문가 타당화 검토 작업을 실시하였다. 전문가 피드백을 반영하여 수정보완된 설계전략을 적용하여 개발된 프로토타입에 대한 학습자의 반응 평가를 통해 설계전략의 효과성을 살펴보았다. 이러닝 환경에서 자기조절학습을 위한 감성조절 지원 인터페이스 프로토타입 설계, 개발에 적용된 최종설계전략은 학습계획, 기분전환, 감성표출, 사회적지지 추구로 구성되며 각 설계전략은 2-3개의 설계지침을 포함하고 있다. 설계전략, 지침을 적용하여 개발된 이러닝 인터페이스 프로토타입에 대한 학습자 반응 평가 결과, 본 프로토타입이 학습자의 긍정 감성을 증진하고 부정 감성을 완화시키는 데 긍정적인 영향을 미치는 것으로 나타났다. 이러닝 인터페이스 설계전략 개발을 통해 확인된 자기조절학습과 감성간의 긴밀한 관계는 감성적 영역의 학습환경 설계로써 교수설계이론의 확장에 기여할 수 있다. 향후 인지, 동기, 행동뿐 아니라 감성조절 차원에서 자기조절학습을 촉진할 수 있는 통합적 교수설계 방안을 모색할 필요가 있다. For successful e-Learning, its interface should be designed and developed to help learners sustain self-regulated learning in their positive emotional states through overcoming their negative emotions such as frustration, anger, anxiety, fear and boredom. The purpose of this study was to develop the design strategies of e-Learning interface supporting emotion regulation for self-regulated learning. The design strategies were initially developed based on related prior research implications and reviewed by experts. Then their effectiveness was explored through learners`` evaluations of an e-Learning interface prototype reflecting the revised design strategies by expert feedback. According to the results of the study, the design strategies for designing interface of supporting emotion regulation for self-regulated e-Learning are planning for learning, distraction, venting emotions, and seeking social support. Each design strategy includes two or three detailed design guidelines. The results of learners`` evaluations of the prototype applying the design strategies show that it is help for inducing their positive emotions and reducing their negative emotions. A close relationship between the self-regulating learning and emotions through this study on the design strategies of emotion regulation supporting e-Learning interface can contribute to the expansion of an instructional design theory as an emotional design of instruction. This research findings suggest a direction to integrated instructional design methods which can support emotion as well as cognition, motivation, and behavior to promote self-regulated learning.