Anomalous Ambipolar Transport of Organic Semiconducting Crystals via Control of Molecular Packing Structures

Park, Beomjin,Kim, Kyunghun,Park, Jaesung,Lim, Heeseon,Lanh, Phung Thi,Jang, A-Rang,Hyun, Chohee,Myung, Chang Woo,Park, Seungkyoo,Kim, Jeong Won,Kim, Kwang S.,Shin, Hyeon Suk,Lee, Geunsik,Kim, Se Hyun American Chemical Society 2017 ACS APPLIED MATERIALS & INTERFACES Vol.9 No.33

<P>Organic crystals deposited on 2-dimensional (2D) van der Waals substrates have been widely investigated due to their unprecedented crystal structures and electrical properties. van der Waals interaction between organic molecules and the substrate induces epitaxial growth of high quality organic crystals and their anomalous crystal morphologies. Here, we report on unique ambipolar charge transport of a 'lying-down' pentacene crystal grown on a 2D hexagonal boron nitride van der Waals substrate. From in-depth analysis on crystal growth behavior and ultraviolet photoemission spectroscopy measurement, it is revealed that the pentacene crystal at the initial growth stage have a lattice-strained packing structure and unique energy band structure with a deep highest occupied molecular orbital level compared to conventional 'standing-up' crystals. The lattice-strained pentacene few layers enable ambipolar charge transport in field-effect transistors with balanced hole and electron field-effect mobilities. Complementary logic circuits composed of the two identical transistors show clear inverting functionality with a high gain up to 15. The interesting crystal morphology of organic crystals on van der Waals substrates is expected to attract broad attentions on organic/2D interfaces for their electronic applications.</P>

Improvements that are often pointed out in regular inspection of experimental animal facility in Seoul National University Hospital

Chohee Hwang,Yunjung Won,Dongwon Lee,Kyoungmin Roh,Sangyoung Park,Eunyoung Cho,Euna Kwon,Jinsung Park,Byeong-Cheol Kang,Kookhyun Lee,Hyeonggon Yu 한국실험동물학회 2019 한국실험동물학회 학술발표대회 논문집 Vol.2019 No.7

인지행동치료 기반 부모훈련 프로그램이 아동학대 가해 부모의 부모양육태도, 부모 자녀간 의사소통 유형, 정서조절곤란에 미치는 영향

박초희 ( Chohee Park ),김정민 ( Jungmin Kim ) 사단법인 아시아문화학술원 2021 인문사회 21 Vol.12 No.1

본 연구는 인지행동치료 기반 부모훈련 프로그램이 아동학대 가해 부모의 가해 행동과 관련된 변인에 미치는 효과를 분석한 연구이다. 가해 부모 총 16명을 대상으로 실험집단 8명, 통제집단 8명을 구성하여, 2019년 5~7월 동안 실험집단에 8회기 인지행동치료 기반 부모훈련 프로그램을 적용하였다. 인지행동치료 기반 부모훈련 프로그램의 효과성을 검증하기 위한 측정 도구를 부모양육태도, 부모 자녀간 의사소통 유형 및 정서조절곤란으로 구성하였고, 집단 간 사전-사후-추후 검사를 비교분석하였다. 연구결과는 실험집단이 통제집단보다 통계적으로 유의한 변화가 있었다. 이러한 연구결과는 인지행동치료 기반 부모훈련 프로그램이 부모의 아동학대 가해 행동을 감소시키고 재학대를 예방하는데 효과적인 방법이 될 수 있음을 시사한다. This study analyzed the effects of cognitive behavioral therapy based parental training programs on variables related to the abused parents’ behaviors. For a total of 16 offender parents, 8 experimental groups and 8 control groups were formed, and the 8th session of cognitive behavioral therapy based parental training programs were applied to the experimental group from May to July 2019. The measuring tools to verify the effectiveness of the cognitive behavioral therapy based parent training program consisted of parenting attitude, communication type between parents and children, and emotional control difficulties, and pre-post tests amd follow-up test four weeks later were compared and analyzed between groups. The study results showed that the experimental group had a statistically significant change than the control group. These findings suggest that cognitive-behavioral therapy-based parental training programs can be an effective method to reduce parental child abuse behavior and prevent re-abuse.

학대 피해 아동의 심리사회적 적응을 위한 위기개입 인지행동놀이치료 프로그램 개발 및 효과

박초희 ( Chohee Park ),김정민 ( Jungmin Kim ) 사단법인 아시아문화학술원 2021 인문사회 21 Vol.12 No.6

본 연구는 학대 피해 아동의 심리사회적 적응을 위한 위기개입 인지행동놀이치료(CBPT) 프로그램을 개발하고 효과성을 검증하는 데 있다. 학대 피해 아동 총 24명을 대상으로 실험집단과 비교집단, 통제집단에 각 8명을 구성하였다. 8주 동안 실험집단은 위기개입 CBPT를, 비교집단은 위기개입 미술치료를 주 1회 실시하였다. 위기개입 CBPT의 효과성을 검증하기 위한 측정 도구는 적대적, 의도적 귀인, 우울, 불안, 공격성으로 구성하였고, 집단 간 사전-사후 검사를 비교분석하였다. 연구결과는 모든 변인에서 실험집단이 비교집단과 통제집단보다 통계적으로 유의한 변화가 있는 것으로 나타났다. 이러한 연구결과는 위기개입 CBPT가 학대 피해 아동의 심리사회적 적응을 증진하는데 효과적인 방법이 될 수 있음을 시사한다. The purpose of this study is to develop and verify the effectiveness of a crisis intervention cognitive behavioral play therapy (CBPT) program for psychosocial adaptation of abused children. A total of 24 children were composed of 8 children each in the experimental group, comparison group, and control group. Once a week for 8 weeks, the experimental group received crisis intervention CBPT, and the comparison group performed crisis intervention art therapy. Measuring tools to verify the effectiveness of the crisis intervention CBPT consisted of hostile, intentional attribution, depression, anxiety, and aggression. The results of the study showed that the experimental group had statistically significant changes in all variables than the control group and the control group. These findings suggest that the crisis intervention CBPT can be an effective method to promote psychosocial adaptation of abused children.

신재생에너지 밀집 연계 지역에서 전기자동차의 영향

박상우(Sangwoo Park),황초희(Chohee Hwang),문혁진(Hyeokjin Moon),박희정(Heejung Park) 대한전기학회 2022 대한전기학회 학술대회 논문집 Vol.2022 No.7

The Effects of Mobile User Interface Red and Blue on Affordance

Won, Chohee,Park, Yungkyung 한국색채학회 2023 한국색채학회 논문집 Vol.37 No.2

Online shopping and e-learning utilizing smartphones are becoming more active. In this process, decision-making such as Yes or No is being made directly on the display. Mobile displays do not provide visual clues, i.e., affordance, for behavior induction, such as properties that can be pressed in the user interface, in physical contact. Therefore, this study aimed to investigate the effect of red and blue graphic user interface on affordance in the mobile environment. The research questions are as follows: First, does hue affect affordance? Second, does tone affect visibility? Third, what is the relationship between visibility and affordance? The PCCS color system was used, and red, blue light tone, vivid tone, grayish tone, and dark tone were selected. Using paired comparison, eight user interfaces were paired sequentially in pairs of two so that all samples could correspond to one-to-one, making a total of 16 pairs. The participants were 26 people in their 20s to 30s, and an iPhone 11 pro was used for the device. When checked by hue, it can be confirmed that red user interface has a higher affordance than blue user interface. The z-score by tone confirmed that red showed a positive (+) value in light, grayish, dark, and vivid tone, but blue showed a negative (-) value in dark, vivid, grayish, and light tone. Therefore, It can also be confirmed that red user interface is the color with high visibility. When considering visibility, the z-score by tone confirmed that red user interface showed a positive (+) value in vivid, light, dark, and grayish tone, but blue user interface showed a negative (-) value in all cases. C*, a factor with a high correlation with visibility, was confirmed. L*, a factor with a high correlation with intuitive choice, was resulted.

Grayness에 따른 저채도 색채감성 연구

원초희(Chohee Won),박영경(Yungkyung Park) 한국색채학회 2020 한국색채학회 학술대회 Vol.2020 No.11

Grayness는 고유색과 비교할 수 있는 지각적 명암을 가지고 있으며 Chromaticness의 영향을 받는다. Chromaticness는 특히 저채도색의 지각에서 중요한 역할을 한다. Grayness와 저채도색의 지각은 관련성 있음이 밝혀졌지만 색채감성에 대한 연구는 많지 않은 실정이다. 따라서 본 연구에서는 Grayness에 따른 저채도 색채감성을 알아보고자 한다. 그 결과 Grayness에 따른 저채도색의 색채감성은 Y는 ‘Passive’, R은 ‘Passive’, ‘Soft’, B, G는 ‘Cool, YR은 ‘Passive’, ‘Soft’, RB는 ‘Cool’, ‘Feminine’, BG는 ‘Cool’, GY는 ‘Soft’, ‘Light’ 감성이 두드러진다. 반면에 Y는 ‘Soft’, ‘Dislike’, R은 ‘Cool’, ‘Light’, B는 ‘Dirty’, ‘Dislike’, G는 ‘Dirty’, ‘Soft’, ‘Dislike’, ‘Light’, YR은 ‘Cool’, ‘Dislike’, RB는 ‘Classical’, ‘Dislike’, BG는 ‘Dirty’, ‘Stale’, GY는 ‘Dirty’, ‘Cool’을 느끼기 어려운 감성으로 나타났다.

Hanging by a thread: Post-attack defense of caterpillars

Kim Yongsu,Park Chohee,No Seongsu,Yoo Sohee,Suh Sung-Suk,Kang Changku 한국응용곤충학회 2022 Journal of Asia-Pacific Entomology Vol.25 No.2

Caterpillars use a diverse range of anti-predator defenses, including camouflage, making and hiding in shelters, mimicry, regurgitating, rolling, and biting. Some caterpillars also drop to the ground and hang themselves by a silk thread. This hanging behavior has been described for a long time but has surprisingly been overlooked in entomological research. In this study, we aimed to identify (1) the taxonomic distribution of the species showing the hanging behavior and (2) the type of sensory stimulus that induces the hanging behavior. We first located caterpillars in the forest and stimulated each caterpillar with three different types of sensory stimuli sequentially: visual approaching, wind-blowing, and poking. For those who responded to none of the stimuli, we further delivered harder tactile stimuli (pinching and detaching from the plants by grabbing) and observed whether they performed the hanging behavior. Among the surveyed 88 species, 46 species (comprising 11 different families) were confirmed to perform the hanging behavior. Most species responded to neither visual nor wind stimulus, but about half of the tested individuals responded to one of the tactile stimuli. Our results suggest that hanging by a silk thread is widespread across a range of lepidopteran groups, and they use this behavior as a post-attack defense

Wafer-Scale and Wrinkle-Free Epitaxial Growth of Single-Orientated Multilayer Hexagonal Boron Nitride on Sapphire

Jang, A-Rang,Hong, Seokmo,Hyun, Chohee,Yoon, Seong In,Kim, Gwangwoo,Jeong, Hu Young,Shin, Tae Joo,Park, Sung O.,Wong, Kester,Kwak, Sang Kyu,Park, Noejung,Yu, Kwangnam,Choi, Eunjip,Mishchenko, Artem,Wi American Chemical Society 2016 Nano letters Vol.16 No.5

<P>Large-scale growth of high-quality hexagonal boron nitride has been a challenge in two-dimensional-material-based electronics. Herein, we present wafer-scale and wrinkle-free epitaxial growth of multilayer hexagonal boron nitride on a sapphire substrate by using high-temperature and low-pressure chemical vapor deposition. Microscopic and spectroscopic investigations and theoretical calculations reveal that synthesized hexagonal boron nitride has a single rotational orientation with AA' stacking order. A facile method for transferring hexagonal boron nitride onto other target substrates was developed, which provides the opportunity for using hexagonal boron nitride as a substrate in practical electronic circuits. A graphene field effect transistor fabricated on our hexagonal boron nitride sheets shows clear quantum oscillation and highly improved carrier mobility because the ultraflatness of the hexagonal boron nitride surface can reduce the substrate-induced degradation of the carrier mobility of two-dimensional materials.</P>

Quantitative analysis of capsaicinoids in Capsicum annuum using HPLC/UV

Gia Han Tran,Hyejin Cho,Chohee Kim,Ohyeol Kweon,Jun Yeon Park,Sullim Lee,Sanghyun Lee 한국응용생명화학회 2023 Journal of Applied Biological Chemistry (J. Appl. Vol.66 No.-

Capsicum annuum belongs to the Solanaceae family, crops of which are extensively cultivated worldwide. It is a food source containing various nutrients and vitamins and also serves as a medicine for treating ailments. The burning feeling experienced while consuming Capsicum fruits is due to the presence of capsaicinoids, particularly capsaicin and dihydrocapsaicin. This study aimed to assess the content of these two compounds in 34 varieties of capsicum and paprika. High-performance liquid chromatography with a gradient elution system and a reversephase YMC Pack-Pro column with UV detection at 280 nm was employed. The results revealed that, among the 34 samples, only six samples (samples 1, 15, 20, 29, 32, and 34) contained capsaicin and dihydrocapsaicin, and their highest contents were found in sample 1 - variety name: Sungil-c (capsaicin: 3.42 mg/g extract, dihydrocapsaicin: 1.20 mg/g extract). These findings suggest that the content of these two compounds is attributed to the variety and is influenced by geographical location and environmental factors. Additionally, this study provides a basis for establishing a C. annuum variety with high capsaicin and dihydrocapsaicin contents.