Neurophysiological and Psychological Predictors of Social Functioning in Patients with Schizophrenia and Bipolar Disorder

Yourim Kim,Aeran Kwon,Dongil Min,Sungkean Kim,Min Jin Jin,Seung-Hwan Lee 대한신경정신의학회 2019 PSYCHIATRY INVESTIGATION Vol.16 No.10

psychological and neurophysiological predictors of social functioning. Methods Twenty-seven patients with schizophrenia and thirty patients with bipolar disorder, as well as twenty-five healthy controls, completed measures of social functioning (questionnaire of social functioning), neurocognition (Verbal fluency, Korean-Auditory Verbal Learning Test), and social cognition (basic empathy scale and Social Attribution Task-Multiple Choice), and the childhood trauma questionnaire (CTQ). For neurophysiological measurements, mismatch negativity and heart rate variability (HRV) were recorded from all participants. Multiple hierarchical regression was performed to explore the impact of factors on social functioning. Results The results showed that CTQ-emotional neglect significantly predicted social functioning in schizophrenia group, while HRVhigh frequency significantly predicted social functioning in bipolar disorder patients. Furthermore, emotional neglect and HRV-HF still predicted social functioning in all of the subjects after controlling for the diagnostic criteria. Conclusion Our results implicated that even though each group has different predictors of social functioning, early traumatic events and HRV could be important indicators of functional outcome irrespective of what group they are.

Finding the Quickest Straight-Line Trajectory for a Three-Wheeled Omnidirectional Robot under Input Voltage Constraints

Kim, Ki Bum,Kim, Yong-Hyuk,Yoon, Yourim Hindawi Limited 2015 Mathematical problems in engineering Vol.2015 No.-

<P>We provide an analytical solution to the problem of generating the quickest straight-line trajectory for a three-wheeled omnidirectional mobile robot, under the practical constraint of limited voltage. Applying the maximum principle to the geometric properties of the input constraints, we find that an optimal input vector of motor voltages has at least one extreme value when the orientation of the robot is fixed and two extreme values when rotation is allowed. We can find an explicit representation of the optimal vector for a motion under fixed orientation. We derive several properties of quickest straight-line trajectories and verify them through simulation. We show that the quickest trajectory when rotation is allowed is always faster than the quickest with fixed orientation.</P>

Improved Correction of Atmospheric Pressure Data Obtained by Smartphones through Machine Learning

Kim, Yong-Hyuk,Ha, Ji-Hun,Yoon, Yourim,Kim, Na-Young,Im, Hyo-Hyuc,Sim, Sangjin,Choi, Reno K. Y. Hindawi Publishing Corporation 2016 Computational intelligence and neuroscience Vol.2016 No.-

<P>A correction method using machine learning aims to improve the conventional linear regression (LR) based method for correction of atmospheric pressure data obtained by smartphones. The method proposed in this study conducts clustering and regression analysis with time domain classification. Data obtained in Gyeonggi-do, one of the most populous provinces in South Korea surrounding Seoul with the size of 10,000 km<SUP>2</SUP>, from July 2014 through December 2014, using smartphones were classified with respect to time of day (daytime or nighttime) as well as day of the week (weekday or weekend) and the user's mobility, prior to the expectation-maximization (EM) clustering. Subsequently, the results were analyzed for comparison by applying machine learning methods such as multilayer perceptron (MLP) and support vector regression (SVR). The results showed a mean absolute error (MAE) 26% lower on average when regression analysis was performed through EM clustering compared to that obtained without EM clustering. For machine learning methods, the MAE for SVR was around 31% lower for LR and about 19% lower for MLP. It is concluded that pressure data from smartphones are as good as the ones from national automatic weather station (AWS) network.</P>

V₂O<SUB>5</SUB> 기반의 금속 산화물 투명 광전소자

김상윤(Sangyun Kim),최유림(Yourim Choi),이경남(Gyeong-Nam Lee),김준동(Joondong Kim) 대한전기학회 2018 전기학회논문지 Vol.67 No.6

All transparent metal oxide photoelectric device based on V₂O5 was fabricated with structure of V₂O5/ZnO/ITO by magnetron sputtering system. V₂O5 was deposited by reactive sputtering system with 4 inch vanadium target (purity 99.99%). In order to achieve p-n junction, p-type V2O5 was deposited onto the n-type ZnO layer. The ITO (indium tin oxide) was applied as the electron transporting layer for effective collection of the photo-induced electrons. Electrical and optical properties were analyzed. The Mott-Schottky analysis was applied to investigate the energy band diagram through the metal oxide layers. The V₂O5/ZnO/ITO photoelectric device has a rectifying ratio of 99.25 and photoresponse ratios of 1.6, 4.88 and 2.68 under different wavelength light illumination of 455 nm, 560 nm and 740 nm. Superior optical properties were realized with the high transmittance of average 70 % for visible light range. Transparent V₂O5 layer absorbs the short wavelength light efficiently while passing the visible light. This research may provide a route for all-transparent photoelectric devices based on the adoption of the emerging p-type V₂O5 metal oxide layer.

Empathy and Social Attribution Skills Moderate the Relationship between Temporal Lobe Volume and Facial Expression Recognition Ability in Schizophrenia

정민지,Seung Yeon Baik,Yourim Kim,Sungkean Kim,Dongil Min,Jeong-Youn Kim,Seunghee Won,이승환 대한정신약물학회 2020 CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE Vol.18 No.3

Objective: While impaired facial expression recognition has been closely associated with reduced temporal lobe volume in patients with schizophrenia, this study aimed at examining whether empathy and social attribution affect such a relationship. Methods: A total of 43 patients with schizophrenia and 43 healthy controls underwent a facial expression recognition task (FERT) and magnetic resonance imaging. Basic empathy scale and the social attribution task-multiple choice were used to measure empathy and social attribution. Results: Patients with schizophrenia showed significant positive correlations between the total temporal lobe volume and the FERT-accuracy (FERT-ACC). Diminished temporal lobe volume predicted the impaired facial emotion recognition ability. Both empathy and social attribution played roles as moderators of the path from the left amygdala volume, left fusiform gyrus volume, both sides of the superior temporal gyrus volume, and left middle temporal gyrus volume to the FERT-ACC. In contrast, empathy alone functioned as a moderator between the right fusiform gyrus volume, right middle temporal gyrus volume, and FERT-ACC. No significant interaction was found for healthy controls. Conclusion: Our results suggest that social cognition remediation training on empathy and social attribution, could buffer the negative effects of small temporal lobe volume on interpersonal emotional communication in patients with schizophrenia.

Frontal Alpha Asymmetry Moderated by Suicidal Ideation in Patients with Major Depressive Disorder: A Comparison with Healthy Individuals

Sang-Choong Roh,Ji Sun Kim,Sungkean Kim,Yourim Kim,Seung-Hwan Lee 대한정신약물학회 2020 CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE Vol.18 No.1

Objective: Frontal alpha asymmetry (FAA) of electroencephalography (EEG) has been studied to differentiate patients with major depressive disorder (MDD) from healthy controls (HC). However, inconsistent results have been obtained thus far. Suicidal ideation (SI) has been known to alter frontal lobe activity, and could be an important covariate in FAA studies. This study aimed to explore the influence of FAA on the relationship among MDD patients with SI and without SI, and HC. Methods: Sixty-seven patients with MDD (44 without and 23 with SI) and 60 HCs were recruited. Resting state EEG was recorded with their eyes open, and FAA as a lateralized index of alpha power was calculated in the frontal brain region. Hamilton Rating Scale for Anxiety and Depression scores were estimated. Results: FAA was higher (increased alpha power in the left frontal region) in the MDD group than in the HC group. The FAA was lower (reduced alpha power in the left frontal region) in MDD patients with SI than in MDD patients without SI. The severity of depression and anxiety symptoms were significantly correlated with FAA only in MDD patients with SI. SI moderated the effects of depressive symptom on FAA in the MDD group. Conclusion: Our results suggest that SI is a clinically important moderator of frontal alpha asymmetry in patients with MDD.

Two Applications of Clustering Techniques to Twitter: Community Detection and Issue Extraction

Kim, Yong-Hyuk,Seo, Sehoon,Ha, Yong-Ho,Lim, Seongwon,Yoon, Yourim Hindawi Limited 2013 Discrete dynamics in nature and society Vol.2013 No.-

<P>Twitter’s recent growth in the number of users has redefined its status from a simple social media service to a mass media. We deal with clustering techniques applied to Twitter network and Twitter trend analysis. When we divide and cluster Twitter network, we can find a group of users with similar inclination, called a “Community.” In this regard, we introduce the Louvain algorithm and advance a partitioned Louvain algorithm as its improved variant. In the result of the experiment based on actual Twitter data, the partitioned Louvain algorithm supplemented the performance decline and shortened the execution time. Also, we use clustering techniques for trend analysis. We use nonnegative matrix factorization (NMF), which is a convenient method to intuitively interpret and extract issues on various time scales. By cross-verifying the results using NFM, we found that it has clear correlation with the actual main issue.</P>

An Efficient Genetic Algorithm for Maximum Coverage Deployment in Wireless Sensor Networks

Yourim Yoon,Yong-Hyuk Kim IEEE 2013 IEEE transactions on cybernetics Vol.43 No.5

<P>Sensor networks have a lot of applications such as battlefield surveillance, environmental monitoring, and industrial diagnostics. Coverage is one of the most important performance metrics for sensor networks since it reflects how well a sensor field is monitored. In this paper, we introduce the maximum coverage deployment problem in wireless sensor networks and analyze the properties of the problem and its solution space. Random deployment is the simplest way to deploy sensor nodes but may cause unbalanced deployment and therefore, we need a more intelligent way for sensor deployment. We found that the phenotype space of the problem is a quotient space of the genotype space in a mathematical view. Based on this property, we propose an efficient genetic algorithm using a novel normalization method. A Monte Carlo method is adopted to design an efficient evaluation function, and its computation time is decreased without loss of solution quality using a method that starts from a small number of random samples and gradually increases the number for subsequent generations. The proposed genetic algorithms could be further improved by combining with a well-designed local search. The performance of the proposed genetic algorithm is shown by a comparative experimental study. When compared with random deployment and existing methods, our genetic algorithm was not only about twice faster, but also showed significant performance improvement in quality.</P>

미용교육의 상호작용적 특성과 지각된가치 및 팬쉽의 관계

이유림 ( Yourim Lee ),김지영 ( Jiyeong Kim ),서예지 ( Yeji Suh ),박은준 ( Eun-jun Pack ) 한국미용학회 2021 한국미용학회지 Vol.27 No.3

The improved economic level has led to the development of the leisure culture of people, and various human needs based on leisure have been expressed. In response, the purpose of this study is to present practical implications related to the importance of learning transfer through communication and trust for the qualitative growth of beauty education, by examining the effect of learner-educator interaction characteristics and students' perceived value on fanship as a beauty educator. For empirical analysis, a self-report survey was conducted on students who had recently taken beauty education, and a total of 506 questionnaires collected from March 4, 2020 to April 24, 2020 (52 days in total) were used as the final analysis data. Through the SPSS 22.0 program, frequency analysis, factor analysis, reliability analysis, and regression analysis were conducted. The main results of this study for beauty trainees are as follows. The main results of this study based on a total of 506 beauty education students are summarized as follows. First, the result of examining the demographic characteristics of the survey subjects showed that the gender and age of beauty education students were women in their 20s and younger. Also, less than a year of total work experience and a monthly average salary of 1 to 2 million Korean won had the highest percentages. Second, according to the result of regression analysis on the effect of interactive characteristics on perceived value, perceived value was significantly influenced by the factors such as receptivity, sensitivity, cognitive involvement, and the accessibility of interactive characteristics. In addition, the influence appeared in the order of receptivity, sensitivity, and cognitive involvement. Third, the result of regression analysis on the influence of interactive characteristics on fanship showed that all sub-elements of interactive characteristics had a positive effect on fanship. Fourth, as a result of regression analysis on the effect of perceived value on fanship, all sub-elements of perceived value had a positive effect on fanship. The study findings demonstrated that the close interaction between students and educators in beauty education and the perceived values of the students can form a positive fanship for beauty educators. This means that beauty education must not only consist of transferring knowledge but also establish a social relationship with students through empathy and communication with them. This implies that rather than giving beauty education to simply cultivate students' knowledge in their major, it is necessary to connect it to an individual's self growth so that the beauty education perceived by them becomes more valuable and meaningful in life.

Quotient geometric crossovers and redundant encodings

Yoon, Yourim,Kim, Yong-Hyuk,Moraglio, Alberto,Moon, Byung-Ro Elsevier 2012 Theoretical computer science Vol.425 No.-

<P><B>Abstract</B></P><P>We extend a geometric framework for the interpretation of search operators to encompass the genotype–phenotype mapping derived from an equivalence relation defined by an isometry group. We show that this mapping can be naturally interpreted using the concept of quotient space, in which the original space corresponds to the genotype space and the quotient space corresponds to the phenotype space. Using this characterization, it is possible to define induced geometric crossovers on the phenotype space (called <I>quotient geometric crossovers</I>). These crossovers have very appealing properties for non-synonymously redundant encodings, such as reducing the size of the search space actually searched, removing the low locality from the encodings, and allowing a more informed search by utilizing distances better tailored to the specific solution interpretation. Interestingly, quotient geometric crossovers act on genotypes but have an effect equivalent to geometric crossovers acting directly on the phenotype space. This property allows us to actually implement them even when phenotypes cannot be represented directly. We give four example applications of quotient geometric crossovers for non-synonymously redundant encodings and demonstrate their superiority experimentally.</P>