http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Yunji Jeong,Jihwan Park,Geonho Cho,Ki-Jeong Hong 한국응용곤충학회 2023 한국응용곤충학회 학술대회논문집 Vol.2023 No.10
The members of genus Donacia are aquatic leaf beetles in the subfamily Donaciinae. Their larvae feed on submerged portions of aquatic plants and adults live on surface parts of the same plants. This genus includes 6 species belonging to 2 subgenera in the Korean Peninsula, of which there have been questions about the record of D. (Donacomima) japana. Ch?j? and Goecke (1956) described a new species, D. japana, based on specimens collected in Japan and Korea (Unggi, Hamgyeongbuk-do), and Hayashi (2020) stated that records of this species from Korea and NE China may be misidentification of D. aquatica (Linnaeus, 1758). In this study, as a result of comparing specimens collected in South Korea (Gwangneung, Gyeonggi-do) with descriptions of D. japana, male genitalia (Hayashi, 2020) and gene sequences of COI region, we conclude that records of D. japana replace with D. aquatica in the Korean Peninsula, and D. japana is endemic to Japan.
Jeong Woo Shin,Sungje Lee,Dohyun Go,Byung Chan Yang,Taeyoung Kim,Sung Eun Jo,Pei-Chen Su,Jihwan An 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.10 No.3
Designing highly active and thermally stable electrodes is crucial for realizing low-temperature solid oxide fuel cells (LT-SOFCs) with excellent performance. In this study, we fabricated an yttria-doped ceria (YDC) shell layer by atomic layer deposition (ALD) over a Pt cathode by controlling the doping concentration of yttria in YDC film. The exchange current density was enhanced by a factor of five when the ALD YDC shell layer was deposited onto the cathode surface compared to the bare Pt cathode, resulting in an 80% decrease in the activation resistance of the 19 mol%-doped ALD YDC-overcoated Pt cathode compared to that of the bare Pt cathode. Furthermore, the thermal stability was enhanced in low-to-medium-doped (7–19 mol%) ALD YDC-coated Pt cathodes, whereas the highly doped (31 mol%) cathode showed a relatively marginal improvement in stability.
A Current-Mode Boost Converter with Wide Bandwidth Inductor Current Sensor
Jihwan Lee(이지환),Junyeol Jeon(전준열),Jeongpyo Park(박정표),Mingyu Jeong(정민규),Jingyu Kang(강진규),Changsik Yoo(유창식) 대한전자공학회 2018 전자공학회논문지 Vol.55 No.10
본 논문은 넓은 주파수 대역폭의 인덕터 전류 센서를 갖는 전류 모드 제어 부스트 컨버터를 소개한다. 제안하는 current-mirror 기반의 인덕터 전류 센서는 추가적인 feedback loop이 없어 높은 정확성과 넓은 주파수 대역폭을 갖는다. 부스트 컨버터는 180-nm BCDMOS 공정으로 제작되었으며 실리콘 면적은 2200-μm × 2200-μm이다. 부스트 컨버터는 1-MHz의 switching 주파수에서 동작하며 3-V의 입력 전압, 3.5-V에서 5-V의 출력 전압 범위를 가진다. 출력 전압 ripple은 33-mV 이내이며 최대효율은 95-%에 달한다. This paper presents a current-mode boost converter with wide bandwidth inductor current sensor. The proposed inductor current sensor is based on current-mirror without any feedback loop, allowing high accuracy and wide bandwidth. The boost converter has been fabricated in a 180-nm BCDMOS process occupying the silicon area of 2200-μm × 2200-μm. Operating at 1-MHz switching frequency, the boost converter provides the output voltage ranging from 3.5-V to 5-V from 3.0-V input. The output voltage ripple is smaller than 33-mV and the peak power efficiency is 95-%.
Jeong, Heonjae,Kim, Jun Woo,Park, Joonsuk,An, Jihwan,Lee, Tonghun,Prinz, Fritz B.,Shim, Joon Hyung American Chemical Society 2016 ACS APPLIED MATERIALS & INTERFACES Vol.8 No.44
<P>Nickel and ruthenium bimetallic catalysts were heterogeneously synthesized via atomic layer deposition (ALD) for use as the anode of direct methanol solid oxide fuel cells (DMSOFCs) operating in a low-temperature range. The presence of highly dispersed ALD Ru islands over a porous Ni mesh was confirmed, and the Ni/ALD Ru anode microstructure was observed. Fuel cell tests were conducted using Ni-only and Ni/ALD Ru anodes with approximately 350 mu m thick gadolinium-doped ceria electrolytes and platinum cathodes. ThC performance of fuel cells was assessed using pure methanol at operating temperatures of 300-400 degrees C. Micromorphological changes of the anode after cell operation were investigated, and the content of adsorbed carbon on the anode side of the operated samples was measured. The difference in the maximum power density between samples utilizing Ni/ALD Ru and Pt/ALD Ru, the latter being the best catalyst for direct methanol fuel cells, was observed to be less than 7% at 300 degrees C and 30% at 350 degrees C. The improved electrochemical activity of the Ni/ALD Ru anode compared to that of the Ni-only anode, along with the reduction of the number of catalytically active sites due to agglomeration of Ni and carbon formation on the Ni surface as compared to Pt, explains this decent performance.</P>
Jeong, Ha-Neul,Ahn, Sang-Il,Na, Minkyun,Yoo, Jihwan,Kim, Woohyun,Jung, In-Ho,Kang, Soobin,Kim, Seung Min,Shin, Ha Young,Chang, Jong Hee,Kim, Eui Hyun The Korean Neurosurgical Society 2021 Journal of Korean neurosurgical society Vol.64 No.2
Objective : Electrooculography (EOG) records eyeball movements as changes in the potential difference between the negatively charged retina and the positively charged cornea. We aimed to investigate whether reliable EOG waveforms can be evoked by electrical stimulation of the oculomotor and abducens nerves during skull base surgery. Methods : We retrospectively reviewed the records of 18 patients who had undergone a skull base tumor surgery using EOG (11 craniotomies and seven endonasal endoscopic surgeries). Stimulation was performed at 5 Hz with a stimulus duration of 200 μs and an intensity of 0.1-5 mA using a concentric bipolar probe. Recording electrodes were placed on the upper (active) and lower (reference) eyelids, and on the outer corners of both eyes; the active electrode was placed on the contralateral side. Results : Reproducibly triggered EOG waveforms were observed in all cases. Electrical stimulation of cranial nerves (CNs) III and VI elicited positive waveforms and negative waveforms, respectively, in the horizontal recording. The median latencies were 3.1 and 0.5 ms for craniotomies and endonasal endoscopic surgeries, respectively (p=0.007). Additionally, the median amplitudes were 33.7 and 46.4 μV for craniotomies and endonasal endoscopic surgeries, respectively (p=0.40). Conclusion : This study showed reliably triggered EOG waveforms with stimulation of CNs III and VI during skull base surgery. The latency was different according to the point of stimulation and thus predictable. As EOG is noninvasive and relatively easy to perform, it can be used to identify the ocular motor nerves during surgeries as an alternative of electromyography.
Predictors of Habitual and Addictive Smartphone Behavior in Problematic Smartphone Use
Jihwan Park,Jo-Eun Jeong,Mi Jung Rho 대한신경정신의학회 2021 PSYCHIATRY INVESTIGATION Vol.18 No.2
Objective Smartphones have become common, and problematic smartphone use (PSU) is increasing. Predictors of PSU should be identified to prevent it. Little is known about the role of content types of smartphone use as predictors of PSU. Therefore, we aimed to evaluate the predictors of two proposed concepts of PSU, namely habitual smartphone behavior (SB) and addictive SB, within the context of the application (app) categories. Methods We studied 1,039 smartphone users using online surveys conducted between January 2 and 31, 2019. We employed multiple regression analysis to identify the predictors of habitual and addictive SB. We controlled for sex and age (mean=39.20). Results Common predictors of habitual and addictive SB were the use of social networking services, games, entertainment apps, and average weekend smartphone usage time. The predictors of habitual SB were the use of web and lifestyle apps, weekly usage frequency, and sex (female) and the predictors of addictive SB were the use of shopping apps and sleep duration. Conclusion This study revealed the need to consider habitual and addictive SB in evaluating PSU. The predictors in terms of the content types of smartphone usage can be used to develop monitoring and prevention services for PSU.
Jeong, Younghun,Park, Jihwan,Yu, Jin,Lee, Sunyeong,Ha, Jihee,Choo, Yeonki,Oh, Taeyoung International Academy of Physical Therapy Research 2019 Journal of International Academy of Physical Ther Vol.10 No.1
Background: There have been many studies on self-myofascial release (SMR) stretching, but there are few comparative studies on the effects of massages using a release ball, which is a type of the SMR method. Objective: To investigate the immediate effects of release ball massage and self-stretching on proprioceptive sensory, hamstring's temperature, range of motion (ROM) muscle strength,. Design: Crossover study. Methods: Thirty women in 20's at S University in Busan voluntarily participated in the study. Participants were random to release ball group (n=15) or self-stretching group (n=15). Both groups performed 3 sets of exercises, stretching for 30 seconds and resting for 15 seconds in each position. The proprioceptive sensory, temperature of the hamstring muscle, ROM, and strength were measured before exercise, 5 minutes after exercise, and 30 minutes after exercise. Results: Release ball group showed significant differences in muscle length and temperature over time (p<.05). The comparison between two group over time showed significant differences in muscle length, temperature, and muscle strength (p<.05). Conclusions: These results demonstrate that release ball massage and self-stretching are beneficial for improving hamstring's temperature, ROM and muscle strength.