Development of a Sensor Knowledge Store Using a Quadtree Algorithm to Support Autonomous Vehicle Path Planning

Jihyun Yoon,Carl D. Crane III 제어로봇시스템학회 2010 제어로봇시스템학회 국제학술대회 논문집 Vol.2010 No.10

This paper presents a Quadtree algorithm which is one of the several possible methods that can be used to store an unknown amount of terrain data. The Quadtree algorithm is often used for visualizing large terrain. The Triangulated Irregular Network (TIN) method has been developed recently but it is difficult to make geographical operations such as neighbor finding, searching, and updating. The purpose of this paper is to show an easy way to implement these operations.

Bone Marrow-derived Side Population Cells are Capable of Functional Cardiomyogenic Differentiation

Yoon, Jihyun,Choi, Seungcheol,Park, Chiyeon,Choi, Jihyun,Kim, Yangin,Shim, Wanjoo,Lim, Dosun Korean Society for Molecular Biology 2008 Molecules and cells Vol.25 No.2

It has been reported that bone marrow (BM)-side population (SP) cells, with hematopoietic stem cell activity, can transdifferentiate into cardiomyocytes and contribute to myocardial repair. However, this has been questioned by recent studies showing that hematopoietic stem cells (HSCs) adopt a hematopoietic cell lineage in the ischemic myocardium. The present study was designed to investigate whether BM-SP cells can in fact transdifferentiate into functional cardiomyocytes. Phenotypically, BM-SP cells were 19.59%±9.00 CD14+, 8.22%±2.72 CD34+, 92.93%±2.68 CD44+, 91.86%±4.07 CD45+, 28.48%±2.24 c-kit+, 71.09%±3.67 Sca-1+. Expression of endothelial cell markers (CD31, Flk-1, Tie-2 and VEGF-A) was higher in BM-SP cells than whole BM cells. After five days of co-culture with neonatal cardiomyocytes, 7.2%±1.2 of the BM-SP cells expressed sarcomeric α-actinin as measured by flow cytometry. Moreover, BM-SP cells co-cultured on neonatal cardiomyocytes fixed to inhibit cell fusion also expressed sarcomeric α-actinin. The co-cultured BM-SP cells showed neonatal cardiomyocyte-like action potentials of relatively long duration and shallow resting membrane potential. They also generated calcium transients with amplitude and duration similar to those of neonatal cardiomyocytes. These results show that BM-SP cells are capable of functional cardiomyogenic differentiation when co-cultured with neonatal cardiomyocytes.

Nannophya pygmaea (Odonata: Libellulidae), an endangered dragonfly in korea, prefers abandoned paddy fields in the early seral stage.

Yoon, Jihyun,Nam, Jong Min,Kim, Heungtae,Bae, Yeon Jae,Kim, Jae Geun Entomological Society of America 2010 Environmental entomology Vol.39 No.2

<P>To characterize habitats of Nannophya pygmaea Rambur (the northern pygmyfly; Odonata: Lilbellulidae), which is endangered in Korea, we analyzed characteristics of surface water and soil, landscape properties, and vegetation types in 22 habitats in eight areas of Korea where nymphs of N. pygmaea have been found since 2005. We divided the habitats into two groups: DS (dwelling site) habitats, where N. pygmaea was observed at the time of the study, and PDS (past dwelling site) habitats, where N. pygmaea recently lived but is no longer found. The habitats were mostly located in former paddy fields on mountain slopes that have been abandoned for 3-7 yr. The main water sources for these habitats were ground water and surface runoff, and the water level was stable at 3-7 cm in depth. The habitats ranged from 300 to 1000 m(2) and were dominated by Juncus effusus, which formed tussock mounds. According to the hydrosere model of succession, N. pygmaea appeared mostly in the early stages of plant succession (the period approximately 3-7 yr after the initiation of succession in former paddy fields) and N. pygmaea preferred habitats displaying the water and soil characteristics that are typical of the early stages of succession in abandoned paddy fields. These results indicate that the primary habitats of N. pygmaea in Korea are recently abandoned paddy fields that are in an oligotrophic state. As succession proceeds in these habitats, N. pygmaea disappears. A habitat management program should be launched to conserve the habitats and populations of N. pygmaea.</P>

Disability-adjusted Life Years for 313 Diseases and Injuries: the 2012 Korean Burden of Disease Study

Yoon, Jihyun,Oh, In-Hwan,Seo, Hyeyoung,Kim, Eun-Jung,Gong, Young-hoon,Ock, Minsu,Lim, Dohee,Lee, Won Kyung,Lee, Ye-Rin,Kim, Dongwoo,Jo, Min-Woo,Park, Hyesook,Yoon, Seok-Jun The Korean Academy of Medical Sciences 2016 JOURNAL OF KOREAN MEDICAL SCIENCE Vol.31 No.suppl2

<P>This study is part of a 5-year research project on the national burden of diseases, injuries, and risk factors in Korea. Using disability-adjusted life years (DALYs), a metric introduced by the 1990 Global Burden of Disease (GBD) project, we performed a comprehensive and detailed assessment of the magnitude and distribution of both fatal and non-fatal health problems in the Korean population. The concept and general approach were consistent with the original GBD study, with some methodological modifications to make the study more suitable for Korea. We computed DALYs for 313 causes in both sexes and nine age groups using the entire population's medical records and newly generated Korean disability weights. In 2012, the dominant disease burden was non-communicable diseases, which accounted for 85.21% of total DALYs, while injuries accounted for 7.77% and communicable, maternal, neonatal, and nutritional disorders for 7.02%. Of the total DALYs, 88.67% were from years lived with disability and 11.32% were from years of life lost due to premature mortality. Diabetes mellitus was the leading cause of DALYs, followed by low back pain, chronic obstructive pulmonary disease, ischemic heart disease, ischemic stroke, cirrhosis of the liver, falls, osteoarthritis, motorized vehicle with three or more wheels, and self-harm. The results reported here identify key health challenges and opportunities for future health interventions and policy changes, and provide information that will help assess the major public health issues in Korea, a nation faced with one of the world's most rapidly ageing populations.</P>

The Non-Communicable Disease Burden in Korea: Findings from the 2012 Korean Burden of Disease Study

Yoon, Jihyun,Seo, Hyeyoung,Oh, In-Hwan,Yoon, Seok-Jun The Korean Academy of Medical Sciences 2016 JOURNAL OF KOREAN MEDICAL SCIENCE Vol.31 No.suppl2

<P>In recognition of Korea's rising burden of non-communicable diseases (NCDs), we investigated the nation's NCD status and extracted detailed information from the 2012 Korean Burden of Disease study. Consistent with that study, we used disability-adjusted life year (DALY) as a metric. Using national data sources and disability weights specific to the Korean population, we analyzed 116 disaggregated NCDs from the study's four-level disease and injury hierarchy for both sexes and nine age groups. Per 100,000 population, 21,019 DALYs were lost to 116 NCDs. Of those, 13.97% were due to premature death (death prior to the standard life expectancy for a subject's age) and 86.03% to non-fatal health outcomes. Based on traditional statistics, the main causes of health loss were mortality of neoplasms; cardiovascular and circulatory diseases; diabetes, urogenital, blood, and endocrine diseases; and chronic respiratory diseases. When combined with analyses of premature death and non-fatal outcomes, however, a substantially different view emerged: the main causes of health loss were diabetes mellitus, low back pain, chronic obstructive pulmonary disease, ischemic heart disease, ischemic stroke, cirrhosis of the liver, osteoarthritis, asthma, gastritis and duodenitis, and periodontal disease (in that order), collectively causing 49.20% of DALYs. Thus, burden of disease data using DALYs rather than traditional statistics brings a new perspective to characterization of the population's health that provides practical information useful for developing and targeting national NCD control programs to better meet national needs.</P>

Differentiation Study on Airline Marketing after Pandemic

Yoon Jihyun,Cheong Yugyeong 한국항공우주의학협회 2023 항공우주의학 학술대회 Vol.2023 No.6

Characterization of amyloid beta oligomers using atomic force microscopy

Jihyun YOON,Joon Won PARK 한국진공학회 2016 한국진공학회 학술발표회초록집 Vol.2016 No.8

A Study on the Development of Arduino-Electrochemical Cell and the Exploration of Educational Possibilities from the Perspective of Learning by Making

Yoon, Jihyun,Cheon, Ji-Hye,Kang, Seong-Joo Korean Chemical Society 2021 대한화학회지 Vol.65 No.3

In this study, the new electrochemical cell device using Arduino and sensor was developed, and experiments of changes in voltage at the time of serial and parallel connection of electrochemical cells were conducted to verify the effectiveness of the device. In addition, in order to examine the educational effects of the device, student's inquiry activities of measuring voltage of electrochemical cells and making objects using the voltage difference were conducted. As a result, it was confirmed that the electrochemical device using Arduino and sensor could not only perform automatic measurements and visualize data but also have a possibility to seek various educational effects through easy coding and modification of the device. Based on the results of students' performance, it was found that experimental activities using the device impart a positive effect not only on the understanding of scientific concepts, but also on the development of the practical ability to apply scientific knowledges to the real life. Educational implications are discussed in terms of 'learning by making'.

Quantifying Burden of Disease to Measure Population Health in Korea

Yoon, Jihyun,Yoon, Seok-Jun The Korean Academy of Medical Sciences 2016 JOURNAL OF KOREAN MEDICAL SCIENCE Vol.31 No.suppl2

<P>Quantitative assessments of the health status of a population are essential to make decisions and set priorities in the field of public health. Changing epidemiologic patterns increase the demand for comprehensive estimates of population health across the full health spectrum, including non-communicable diseases and injuries. Burden of disease (BoD) analysis has helped meet this need. With the success of the Global Burden of Disease (GBD) Study, the BoD technique has become predominantly associated with the GBD approach and its methodology using disability-adjusted life year (DALY) has been rapidly disseminated and generally accepted over the last several years. The first Korean BoD study using the DALY metric was presented in 2002. Various BoD studies have since been conducted, but the DALY concept has remained primarily academic and has not yet been actively utilized in the health policy arena. Here, we review the DALY metric and population-based Korean BoD studies using national health data, with the intent of increasing the understanding of their value and their potential role in strengthening future assessments of the Korean population’s health status.</P>

The effects of Korean Red Ginseng on stress-related neurotransmitters and gene expression: A randomized, double-blind, placebo-controlled trial

Jihyun Yoon,Byoungjin Park,Kyung-Won Hong,Dong-Hyuk Jung 고려인삼학회 2023 Journal of Ginseng Research Vol.47 No.6

Background: Korean Red Ginseng (KRG) is an effective anti-stress treatment. In this study, we investigatedthe therapeutic potential effects of KRG on relieving stress in a general population using transcriptomeanalysis. Methods: We conducted an 8-week clinical pilot study on 90 healthy men who reported stress. The studywas completed by 43 participants in the KRG group and 44 participants in the placebo group. Participantswere randomized 1:1 to the KRG and placebo groups. We evaluated the stress by stress responseinventory (SRI) at baseline and 8 weeks. The main outcomes were changes in the levels of neurotransmitters(NTs) and NT-related gene expression. NTs were analyzed using automated (GC) content, andlevels of gene expression were measured by reads per kilobase of transcript per million mapped reads(RPKM). Results: The KRG group showed significantly preserved epinephrine decrease compared with placebogroup at 8 weeks (changes in epinephrine, KRG vs. placebo; 1623.2 ± 46101.5 vs. 35116.3 ± 86288.2,p ¼ 0012). Among subjects who higher SRI score, meaning stress increased compared to baseline, theKRG group showed a smaller decrease in serotonin than the placebo group (changes in serotonin, KRG vs. placebo; 2627.5 ± 5859.1 vs, 8087.4 ± 7162.4, p ¼ 0.005) and a smaller increase in cortisol than theplacebo group (changes in cortisol, KRG vs. placebo; 1912.7 ± 10097.75 vs. 8046.2 ± 8050.6 , p ¼ 0.019) insubgroup analysis. Transcriptome findings indicated that KRG intake affects gene expression related withmetabolism of choline, adrenalin, and monoamine. Conclusion: These findings suggest that KRG has beneficial effects on the amelioration of stress responsein NTs, and this effect is more prominent in stressful situations. Further clinical studies are required toconfirm the anti-stress effect of KRG.