http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Kim, Jooyoung,Kim, Junhyeong,Kim, Hyunki,Ahn, Sang Hyun American Chemical Society 2019 ACS APPLIED MATERIALS & INTERFACES Vol.11 No.34
<P>Hydrogen production via a proton exchange membrane water electrolyzer (PEMWE) is an essential technology to complement discontinuity of renewable energies. Development of a high-efficiency and cost-effective gas diffusion electrode (GDE), which is a key component of this technology, remains a challenge. Here, we report a high-performance Ni phosphide GDE prepared by simple electrochemical methods. Selective leaching of excess Ni in electrodeposited Ni<SUB><I>x</I></SUB>P<SUB>1-<I>x</I></SUB> enabled fabrication of a nanoporous NiP GDE with a large electrochemical surface area (ECSA). In half-cell tests, the nanoporous NiP GDE demonstrated a hydrogen-evolving current density of −10 mA/cm<SUP>2</SUP> at an overpotential of 103 mV with good stability. In the single-cell tests, the PEMWE employing a nanoporous NiP cathode exhibited a current density of 1.47 A/cm<SUP>2</SUP> at a cell voltage of 2.0 V, which was the competitive performance among state-of-the-art non-noble cathodes reported to date.</P> [FIG OMISSION]</BR>
Kim, Junhyeong,Kim, Hyunki,Kim, Jooyoung,Kim, Jung Hwan,Ahn, Sang Hyun Elsevier 2019 JOURNAL OF ALLOYS AND COMPOUNDS Vol.807 No.-
<P><B>Abstract</B></P> <P>The development of high-performance gas diffusion electrodes is essential for the fabrication of efficient proton exchange membrane water electrolyzers (PEMWEs) and thus for clean hydrogen production. Herein, we electrodeposited Fe-based binary and ternary phosphides on porous carbon paper (CP) as a substrate and demonstrated that, under optimized deposition conditions (i.e. when the P content was maximum), amorphous FeCoP showed the highest intrinsic activity for hydrogen evolution in an acidic medium. This behavior was ascribed to appropriate electronic structure modification and the alloying effect. Further enhancement of hydrogen evolution performance was achieved by increasing the electrochemical surface area of FeCoP by using a porous Cu foam (CF) support. In a half-cell test, the FeCoP/CF/CP electrode featured an acceptably stable cathodic current of −10 mA/cm<SUP>2</SUP> at an overpotential of −125 mV. A PEMWE single cell with an FeCoP/CF/CP cathode exhibited a current density of 0.95 A/cm<SUP>2</SUP> at a cell voltage of 2.0 V, which is superior to or comparable with previously reported values. Thus, the developed electrode might be a promising alternative to Pt-based cathodes in practical PEMWE applications.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Fe-based transition metal phosphides were electrodeposited on porous carbon paper. </LI> <LI> FeCoP/carbon paper (CP) showed the highest HER intrinsic activity. </LI> <LI> The electrochemical surface area of FeCoP was increased by using a Cu foam support. </LI> <LI> PEMWE with a FeCoP/CF/CP cathode featured a current density of 0.95 A/cm<SUP>2</SUP> at 2.0 V. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
김선희(Sunhee Kim),이주영(Jooyoung Lee),최서경(Seo Gyeong Choi),지승훈(Seunghun Ji),강지민(Jeemin Kang),김종인(Jongin Kim),김도희(Dohee Kim),김보령(Boryoung Kim),조은기(Eungi Jo),김호정(Hojeong Kim),장정민(Jungmin Jang),김준형(Jun Hyung 한국음성학회 2020 말소리와 음성과학 Vol.12 No.4
본 논문은 응급의료 환경에서 음성인식 성능을 향상시키기 위하여 실제 환경에서 데이터 수집 방법을 정의하고 정의된 환경에서 수집된 데이터를 전사하는 방법을 제안한다. 그리고 제안된 방법으로 수집되고 전사된 데이터를 이용하여 기본 음성인식 실험을 진행함으로써 제안한 수집 및 전사 방법을 평가하고 향후 연구 방향을 제시하고자 한다. 모든 음성은 기본적으로 16비트 해상도와 16 kHz 샘플링으로 저장되었다. 수집된 데이터는 총 166건의 대화로서 8시간 35분의 분량이다. 수집된 데이터는 Praat를 이용하여 철자 전사, 음소 전사, 방언 전사, 잡음 전사, 그리고 의료 코드 전사를 수행하여 다양한 정보를 포함한 텍스트 데이터를 구축하였다. 이와 같이 수집된 데이터를 이용하여 기본 베이스라인 실험을 통하여 응급의료 영역에서의 음성인식 문제를 실제로 확인할 수 있었다. 본 논문에서 제시한 데이터는 응급의료 영역의 1단계 데이터로서 향후 의료 영역에서의 음성인식 모델의 학습 데이터로 활용되고, 나아가 이 분야의 음성기반 시스템 개발에 기여할 수 있을 것으로 기대된다. This paper describes a method of building Korean conversational speech data in the emergency medical domain and proposes an annotation method for the collected data in order to improve speech recognition performance. To suggest future research directions, baseline speech recognition experiments were conducted by using partial data that were collected and annotated. All voices were recorded at 16-bit resolution at 16 kHz sampling rate. A total of 166 conversations were collected, amounting to 8 hours and 35 minutes. Various information was manually transcribed such as orthography, pronunciation, dialect, noise, and medical information using Praat. Baseline speech recognition experiments were used to depict problems related to speech recognition in the emergency medical domain. The Korean conversational speech data presented in this paper are first-stage data in the emergency medical domain and are expected to be used as training data for developing conversational systems for emergency medical applications.
Kim, Seonghyeop,Kim, Jooyoung,Hyeok Kim, Jin Elsevier 2017 Ceramics international Vol.43 No.11
<P><B>Abstract</B></P> <P>Insulated metal substrates (IMSs) were fabricated and characterized using an organic ceramic composite as a coating mixture. Organic‐inorganic sol solutions were prepared by a sol‐gel process using TEOS (tetraethylorthosilicate), MTMS (methyltrimethoxysilane) and PhTMS (phenyltrimethoxysilane). Ceramic fillers were composed of aluminum oxide (1 and 4µm) and silicon nitride. The optimal ratio of ceramic filler in the coating mixture was found to be 70wt%. A thermal conductivity of 3.16W/mK and a breakdown voltage of 4kV with a leakage current of 0.17mA/cm<SUP>2</SUP> were obtained for the 122µm-thick film. A well-networked microstructure between the sol resin and filler in the organic ceramic composite films enhanced the properties of the IMS, such as thermal conductivity and electric insulation.</P>
The Influence of Life Stress and Sleep Disturbance on White Matter Integrity
Kim Minjeong,Lee Jiye,Kim Nambeom,Hwang Yunjee,Lee Kyung Hwa,Lee Jooyoung,Lee Yu Jin,Kim Seog Ju 대한신경정신의학회 2023 PSYCHIATRY INVESTIGATION Vol.20 No.5
Objective This study investigated whether sleep and stress mutually interact to induce changes in white matter integrity.Methods Diffusion tensor imaging (DTI) was conducted on 36 participants (male=22, female=14; mean age=38.33±12.78 years). Participants were divided into three groups depending on their sleep quality and stress levels: poor sleepers with stress, poor sleepers without stress, and good sleepers. Sleep quality and stress level were evaluated using the Pittsburgh Sleep Quality Index and the Life Experiences Survey, respectively. Fractional anisotropy (FA) values were calculated employing DTI tractography.Results After controlling for age and sex, poor sleepers with stress exhibited a lower FA of the left inferior cerebellar peduncle (ICP) than did poor sleepers without stress (t=2.81, p=0.02). Poor sleepers without stress showed a higher FA of the right middle longitudinal fasciculus (MdLF) than did good sleepers (t=3.35, p=0.006).Conclusion The current study reports the effects of sleep, stress, and their interaction on the white matter integrities of the ICP and MdLF. ICP change seems to be associated with sleep disturbances related to stress, while MdLF change would be associated with sleep disturbances unrelated to stress.
Jooyoung Kim,MyungIn Ji,Youngsu Cho,Yangkoo Lee,Sangjoon Park 제어로봇시스템학회 2013 제어로봇시스템학회 국제학술대회 논문집 Vol.2013 No.10
The fingerprinting has been considered as a promising method for indoor localization due to the robustness from the multi-path than other methods exploiting wireless signals. However, the fingerprinting method has serious limitation which it requires too much time and cost to construct a DB (Data Base) before positioning. In conventional static collection based fingerprint DB generation system, it usually takes up to several minutes to obtain a radio pattern for a single reference point comprising very small part of whole service areas. To overcome the drawback, the fingerprint DB generation system based on the dynamic collection, which breaks the tradition of the radio pattern collection, is proposed. In contrast to the conventional collection method, a collector carrying a smart-phone moves pre-designated routes in service areas, and the position and the radio patterns are autonomously gathered by the collecting application in the smart-phone at every seconds. With the dynamically collected data, then, the fingerprint DB is finally generated by averaging method. From the experimental results, it is validated that the proposed collection method remarkably improves the efficiency of the collection. Also, the positioning using the generated DB shows reasonable accuracy, 2.62m, in an indoor office environment.
Jooyoung Kim,Jaewoo Do 보안공학연구지원센터 2016 International Journal of Software Engineering and Vol.10 No.12
National Competency Standards (NCS) are defined as required knowledge, skills and attitudes needed to execute one’s duties at work; these are systematized by business sectors and level of ability. To create a competence based society, the South Korean government has established NCS and have promoted the application of NCS in vocational education areas. In accordance with the government’s effort, universities, government institutions, and companies are trying to apply NCS into their system. Particularly, universities have developed NCS-based curriculum and offer courses which are developed based on national competency standards. However, a standardized assessment tool for instructors has not been developed as of yet. With absence of an assessment instrument, instructors are struggling to assess students’ NCS vocational competency. This study developed the performance assessment instrument to assess NCS communication skills, and tested the validity of developed instrument. Developed performance assessment instrument enables the objective and coherent assessment of students’ communication skills. This study will contribute to the development of an assessment instrument for assessing other vocational basic skills.