Impact of Changes in Medical Aid Status on Health Care Utilization

( Woorim Kim ),( Chung Mo Nam ),( Sang Gyu Lee ),( Sohee Park ),( Tae Hyun Kim ),( Eun-cheol Park ) 한국보건행정학회 2019 보건행정학회지 Vol.29 No.4

Background: South Korea operates a Medical Aid (MA) program targeting selected low-income individuals to ensure medical service delivery to the disadvantaged while enhancing self-sufficiency of work-capable beneficiaries. However, as reasons behind welfare exits are diverse and do not always infer poverty relief or the provision of appropriate levels of health care services, this study aimed to investigate the association between changes in MA status and health care utilization. Methods: This study used the 2006 to 2015 National Health Insurance claims data. The impact of changes in annual MA status on health care utilization (yearly number of outpatient visits, inpatient visits, length of stay, and emergency department [ED] visits) was investigated using the generalized estimating equation model. Results: In 117,943 adult subjects aged 20 to 64, compared to the ‘MA to MA’ group, the ‘MA to MA exit’ group showed general decreases in utilization (outpatient visits: β=-3.93, p<0.0001; hospital admissions: relative risk [RR], 0.87; 95% confidence interval [CI], 0.83-0.91; length of stay: β=-3.64, p<0.0001; ED visits: RR, 0.83; 95% CI, 0.77-0.90). Similar patterns were found in the ‘MA exit to MA exit’ group (outpatient visits: β=-5.72, p<0.0001; admissions: RR, 0.91; 95% CI, 0.87-0.94; length of stay: β=-5.87; p<0.0001; ED visits: RR, 0.81; 95% CI, 0.75-0.88). Likewise, in 74,747 older adult subjects aged 65 or above, the ‘MA to MA exit’ group showed reduced levels of utilization (outpatient visits: β=-1.51; p=0.0020), as well as the ‘MA exit to MA exit’ group (admissions: RR, 0.92; 95% CI, 0.89-0.95; length of stay: β, -5.45; p<0.0001; ED visits: RR, 0.90; 95% CI, 0.83-0.97). Conclusion: MA exit was associated with general decreases in health care utilization. Utilization patterns of individuals with experiences of receiving MA benefits should be monitored to promote the ideal use of health care services while preventing potential financial barriers present in accessing medical care.

The Ability to Rest at Home During COVID-19 Symptom Manifestation and Depressive Symptoms: Evidence From Korea

Woorim Kim,Yeong Jun Ju,Soon Young Lee 대한신경정신의학회 2022 PSYCHIATRY INVESTIGATION Vol.19 No.2

Objective This study investigated the association between ability to rest at home in times of coronavirus disease 2019 (COVID-19) symptom manifestation and depressive symptoms.Methods The 2020 Korea Community Health Survey data were used. The presence of depressive symptoms was determined using the Patient Health Questionnaire-9. The relationship between depressive symptoms and ability to rest at home was examined using logistic regression analysis. Additional analysis was performed on the reasons for the inability to stay at home.Results Depressive symptoms were more common in participants who could not rest at home if symptoms manifested (4.1%) than those who could rest at home (2.7%). Participants who could not rest at home (OR 1.53, 95% CI 1.34–1.74) were more likely to have depressive symptoms, particularly when they had to report to work (OR 1.50, 95% CI 1.30–1.74) or purchase daily necessities (OR 2.40, 95% CI 1.15–5.03).Conclusion Inability to rest at home in the case of COVID-19 symptom manifestation was associated with depressive symptoms. The findings suggest the need to address the identified vulnerable groups to mitigate the mental health consequences of the pandemic.

Numerical Simulation of Bubble Growth and Heat Transfer During Flow Boiling in a Surface-Modified Microchannel

Lee, Woorim,Son, Gihun Taylor Francis 2014 Heat transfer engineering Vol.35 No.5

마이크로 핀 표면 핵비등에서의 기포거동에 대한 수치적 연구

이우림(Woorim Lee),손기헌(Gihun Son) 대한기계학회 2011 대한기계학회 춘추학술대회 Vol.2011 No.4

열전달 향상을 위한 방법으로 많이 사용되고 있는 마이크로 핀을 포함한 표연 위에서의 핵비등에 대한 수치해석을 수행하였다. 핵비등에서의 기포거동을 계산하기 위해 sharp-interface 레벨셋(level-set) 방법을 상변화 효과와 핀에서의 접촉각 및 마이크로 액체층에서의 증발 열유속을 포함하도록 수정하였다. 핀과 캐비티를 포함한 표면에서의 기포 생성, 성장, 이탈에 대한 해석을 통하여 핀-캐비티 간격, 핀-핀 간격이 핵비등에서의 기포거동에 중요한 역할을 하는 것을 확인하였다. Numerical simulation is performed for nucleate boiling on a micro-finned surface, which has been widely used to enhance heat transfer, by solving the equations governing conservation of mass, momentum and energy in the liquid and vapor phases. The bubble motion is determined by a sharp-interface level-set method, which is modified to include the effect of phase change and to treat the no-slip and contact-angle conditions as well as the evaporative heat flux from the liquid microlayer on immersed solid surfaces such as micro fins and cavities. The numerical results for bubble formation, growth and departure on a microstructured surface including fins and cavities show that the bubble behavior during nucleate boiling is significantly influenced by the fm-cavity arrangement and the fin-fin spacing.

Comamonas piscis sp. nov., isolated from the intestine of a Korean rockfish, Sebastes schlegelii

Kang, Woorim,Soo Kim, Pil,Hyun, Dong-Wook,Lee, June-Young,Sik Kim, Hyun,Joon Oh, Sei,Shin, Na-Ri,Bae, Jin-Woo Microbiology Society 2016 International journal of systematic and evolutiona Vol.66 No.-

염소 및 브롬 산화제 자외선 광분해 수처리에서의 산화 효율 및 소독부산물 생성 특성 파악

이우림 ( Woorim Lee ),이유리 ( Yuri Lee ),이윤호 ( Yunho Lee ) 한국물환경학회 2020 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2020 No.-

조류독소, 의약물질, 내분비계 교란물질 등의 신종오염물질을 처리하기 위하여 라디칼을 발생시킬 수 있는 고도산화공정이 연구 및 사용되고 있다. 본 연구에서는 수처리에서 유리 염소 및 브롬 산화제의 (HOX 및 OX-, X = Cl 또는 Br) UV_254nm 광분해 동안 산화제 분해 속도 및 ^ㆍOH, X^ㆍ, XO₃^-의 생성 수율을 조사하였다. 라디칼 생성에 대한 산화제의 고유 양자 수율은 라디칼 소거제인 삼차 부틸 알코올 존재 하에서의 포름알데하이드 형성 분석 및 모델 피팅을 통하여, HOCl, OCl^-, HOBr, OBr^-에 대해 각각 0.61, 0.45, 0.32, 0.43으로 결정되었다. HOCl과 OCl^- 광분해에서의 비교적 작은 라디칼 발생 속도의 차이는 (약 1.5배) 나이트로벤젠의 제거속도로 파악한 23배 이상의 ^ㆍOH 정상상태농도 ([^ㆍOH]_ss) 차이를 완전히 설명하지 못하지만, 이는 상대적으로 느린 ^ㆍOH와 HOCl의 반응속도 차이, 즉 라디칼 소거 효과의 차이로 설명할 수 있다. 라디칼 소거 효과를 결정하는 속도상수k_OH,HOCl 값은 경쟁 반응속도법을 사용하여 1.4(±0.2)×10⁸ M^-1s^-1로 측정되었으며, 이는 같은 방법으로 측정한 ^ㆍOH 와 OCl-의 반응 (k_OH,OCl- = 2.0(±0.5)×10⁹ M^-1s^-1) 에 비하여 약 14배 낮은 값을 가짐으로 UV/HOCl 시스템에서의 높은 산화 효율 ([^ㆍOH]_ss) 을 잘 설명한다. XO₃^- 형성에 대한 겉보기 양자 수율은 HOCl, OCl^-, HOBr, OBr^-에 대해 각각 0.23, 0.19, 0.12, 0.18로 측정되었으며, 삼차 부틸 알코올 첨가 시 염소와 ^ㆍOH 반응속도의 차이로 인하여 UV/OCl^- 에 비해 UV/HOCl 시스템에서의 ClO₃^- 형성이 더욱 효과적으로 억제되었다. 본 연구에서 결정된 새로운 광화학·동역학 인자 및 기존문헌에 보고된 반응에 기초하여 동역학 모델을 구축하였다. 이를 활용하여 UV/염소 및 UV/브롬 시스템에서 라디칼 생성, 산화효율 및 XO₃^- 형성을 시뮬레이션 하였으며, XO₃^- 의 생성 경로를 파악하였다.

마이크로 Groove에서 액적충돌에 대한 수치적 연구

이루림(Woorim Lee),서영호(Youngho Suh),손기헌(Gihun Sin) 대한기계학회 2009 大韓機械學會論文集B Vol.33 No.10

Microdroplet deposition in a micro-groove is studied numerically. The droplet shape is determined by a level-set method which is improved by incorporating a sharp-interface modeling technique for accurately enforcing the matching conditions at the liquid-gas interface and the no-slip and contact angle conditions at an immersed solid surface. The computations are carried out to investigate the droplet behavior derived by the interfacial characteristics between the liquid-gas-solid phases. The effects of contact angle, impact velocity and groove geometry on droplet deposition in a micro-groove are quantified.

마이크로 groove에서 액적충돌을 포함한 마이크로라인 패터닝 공정에 대한 수치적 연구

이우림(Woorim Lee),손기헌(Gihun Son) 대한기계학회 2009 대한기계학회 춘추학술대회 Vol.2009 No.11

Microdroplet impact on a micro-groove, which can be used to produce very narrow micro-lines, is studied numerically. The droplet interface is tracked by a sharp-interface level-set method, which is extended to treat the no-slip and contact angle conditions at an immersed solid surface. The computations are performed to investigate a liquid filling process in a micro-groove whose width is narrower than the typical width (20~50㎛) to be obtained from the droplet impact on a flat substrate. Based on the numerical results, the effects of contact angle, groove geometry and impact velocity on the droplet deposition and liquid filling time are quantified.

Does having various types of fear related to COVID-19 disrupt individuals’ daily life?: Findings from a nationwide survey in Korea

Kim Woorim,Ju Yeong Jun,이순영 한국역학회 2022 Epidemiology and Health Vol.44 No.-

OBJECTIVES: Unexpected changes in daily routines caused by the coronavirus disease 2019 (COVID-19) pandemic may affect psychological health. This study investigated the association between various types of COVID-19-related fear and the subjective level of disturbance in daily activities experienced by individuals. METHODS: This cross-sectional study used the Korea Community Health Survey conducted from August through November 2020. COVID-19-related fear included fear of infection, death, public criticism, family members getting infected, and economic loss. The subjective level of disruption in daily activities was measured using a 0-100 numeric rating scale developed by the Korea Disease Control and Prevention Agency. Multivariable linear regression was used to analyze the associations between the independent and dependent variables. A subgroup analysis was performed based on income level. RESULTS: Participants who reported fear of infection (β= -3.37, p< 0.001), death (β= -0.33, p= 0.030), public criticism (β= -1.63, p< 0.001), a family member getting infected (β= -1.03, p< 0.001), and economic loss (β= -3.52, p< 0.001) experienced more disturbances in daily activities. The magnitude of this association was most significant in the lowest-income group. CONCLUSIONS: Individuals reporting COVID-19-related fear experienced higher levels of subjective disruption in daily activities.

Bubble Dynamics and Heat Transfer During Nucleate Boiling in a Microchannel

Lee, Woorim,Son, Gihun Taylor Francis 2008 NUMERICAL HEAT TRANSFER PART A-APPLICATIONS - Vol.53 No.10

<P> The bubble dynamics and heat transfer associated with nucleate boiling in a microchannel is studied numerically by solving the equations governing conservation of mass, momentum, and energy in the liquid and vapor phases. The liquid-vapor interface is tracked by a level set method which is modified to include the effects of phase change and contact angle. Also, the method is coupled with a simple and efficient model for predicting the evaporative heat flux from the liquid microlayer. The effects of channel size, contact angle, and wall superheat on the bubble growth and heat transfer in a microchannel are investigated.</P>