Examination of Synthetic Control Methods to Evaluate a Community-Based Traffic Safety Program in South Korea

Kim, HyoungAh(김형아) 서울행정학회 2020 한국사회와 행정연구 Vol.30 No.4

본 연구는 2013년부터 한시적으로 실시된 “교통안전시범도시” 프로그램을 준실험방법인 Synthetic Control Method(SCM)을 사용하여 평가하였다. “교통안전시범도시” 프로그램은 2013년도부터 2017까지 부산 사상구에서 시행한 시범사업으로 주민참여를 사업 운영의 기반으로 하여, 해당 지역의 교통안전 제고를 위해 필요한 안전시설 설치 및 주민교육실시 등 지역중심의 복합적인 교통안전 프로젝트이다. 이와 같은 사업의 효과를 평가할때, 사업이 실시된 지역(처리집단)의 수가 작다는 비교 연구의 한계가 항상 존재한다. 이를 극복하기 위해, 본 연구에서는 SCM 방법을 사용하였다. 그 결과, 사업이 집행된 지역은 “교통안전시범도시” 사업이 시행된 후 교통사고 수가 통계적으로 유의하게 줄어들었다. 또한, 사고로 인한 부상자 수도 줄어든 것으로 나타났다. 그러나, 교통사고로 인한 사망자 수에는 큰 영향이 없는 것으로 밝혀졌다. 이 논문의 또 다른 목적은, 정책분석을 하는 데 있어 가장 적합한 방법인 실험연구설계(experimental research design)의 어려움을 극복하기 위한 대안 중 하나인 SCM기법을 소개하는 것이다. SCM으로 추정된 정책효과값(정책시행 전후 RMSPE의 비)으로 정책 효과의 크기를 계량화하고, 비모수통계기법중 하나인 permutation test를 통해 통계적 유의성을 측정하는 방식을 소개하고자 한다. This study evaluates the traffic safety program, titled “the Pilot City for Traffic Safety Project”, in South Korea. To estimate program effects on road safety at the local government level, I use a synthetic control method (SCM), widely used to estimate the effect of policy intervention on an outcome variable. In this study, for example; three variables are used-the number of traffic accidents, the number of injuries, and the number of deaths. The results indicate that the road safety program in Korea was effective to reduce the overall number of traffic accidents (The ratio of pre- and post-intervention RMSPE was 5.3 with a 0.06 p-value) and marginally effective to decrease the number of injuries (the ratio of RMSPE was 3.1 with a 0.12 p-value). In contrast, the result for the number of death from traffic accidents shows that there is no strong evidence of the program effect. These findings suggest that the community-based traffic safety program was ineffective in lowering the number of fatal traffic accidents, but would help to reduce the non-fatal traffic accidents in a community. In addition to the policy implication, this study introduces the policy evaluation tool, a SCM, as a useful method to verify the casual effect of a policy intervention in social science. Under the problem of small sample size and randomization issue, SCM will help to systemically build a control group as a counterfactual so that a researcher can measure an effect of policy intervention more thoroughly.

제주도 코로나-19 확산 패턴 분석 - 지역신문 스크래핑 기술과 텍스트 분석(Text Analysis)의 활용 -

Hyoungah Kim 위기관리 이론과 실천 2022 Crisisonomy Vol.18 No.2

Researchers are able to adopt a text scrapping method to collect data from news articles when data are not available due to privacy protections. This study introduces the processes of text scrapping and analyzing texts of news articles from a local news server in Jeju-do. Since the Jeju government regularly discards the path information of COVID-19 patients, researchers who want to explore characteristics of places where a high number of confirmed cases occurred have predicaments in collecting relevant information. To overcome this challenge for social researchers, this study shows a text analysis process including pre-processing, calculating TF-IDF, creating word clouds, and conducting a word network analysis. The results from analyzing 4500 news articles confirm that there was a serial correlation between the number of daily COVID-19 cases and the number of articles and explore specific features of the places where COVID-19 patients went through. The article would help social researchers to use big data and text mining methods in order to overcome the difficulties of data collection in public administration. 정부는 개인정보보호와 프라이버시 때문에 연구자가 필요한 데이터를 공개하지 않기도 한다. 이때연구자는 필요한 데이터를 인터넷에 있는 다양한 정보로부터 수집하기 위해 기사 스크래핑(scrapping)방법을 사용할 수 있다. 본 연구에서는 제주도 지역 확진자 동선 정보가 연구 목적으로 공개되지 않는다는 점에 착안하여, 지역 신문 기사를 수집하고 수집된 기사에 텍스트 분석(text analysis) 기법을 활용하여 필요한 정보를 획득하는 일련의 절차를 소개한다. 한글 텍스트의 전처리(preprocessing) 과정을 거쳐 확산 시기별 핵심 키워드를 추출해 데이터를 구축하고, 이를 바탕으로 워드클라우드(word cloud) 및 단어 네트워크 분석(word network analysis)을 통해 2020년 1월부터 2021년10월까지 제주 지역신문 기사 4500개를 분석한 결과, 코로나-19 확진자 수와 기사수가 시계열적상관관계가 있다는 점과 확진자 수에 따른 확진자 동선관련 정보를 추출해 낼 수 있는 가능성을밝혀냈다. 본 연구에서 소개한 텍스트 분석 과정과 빅데이터 활용 방법이 앞으로 행정학 분야에더욱 활발하게 사용되기를 기대해본다.

정치경제학적 관점에서 본 ICT 분야의 R&D 지출과 국제표준 제안의 상관관계 연구

김형아 ( Hyoungah Kim ),박수빈 ( Subeen Park ) 중앙대학교 국가정책연구소 2019 국가정책연구 Vol.33 No.4

본 연구의 목적은 우리나라 표준 및 표준화 정책의 변화를 정치경제학적 관점에서 살펴봐야 함을 설파하고, 정치경제학적 관점에서 정부 ICT 정책의 기조에 따라 이 분야의 R&D 지출과 국제표준 제안 수의 상관관계가 어떻게 변했는지 실증적으로 살펴보는 것이다. 연구결과 지난 16년 동안 ICT 분야는 우리나라 경제의 성장동력으로 인식되어 정부의 지속적인 지원을 받은 것으로 나타났다. 그에 따라, 이 분야의 국가표준 규모와 국제표준 제안 수가 꾸준하게 상승했다. 실증분석을 위해 교차상관함수(cross-correlation function)를 사용하여 두 시계열 변수(R&D지출과 국제표준 제안 수)를 분석한 결과, 두 변수는 양(+)의 관계가 있는 것으로 나타났다(lag=0과 1). 그러나 정부가 표준관리방식을 시장주의 방식으로 바꾼 후에는 국제표준 제안 수가 감소하거나 완만하게 증가하는 추세를 보였다. 이 결과는 표준정책이 기술의 발전, 국가의 지원, 시장의 완숙이라는 세 요소의 접합점에서 성공을 이룬다고 가정했을 때, 국제표준 수를 늘리기 위해서는, 정부의 시기적절한 지원이 필요하다는 의미를 제공한다. 왜냐하면, 기술의 발전과 시장의 완숙은 자연적으로 발생하는 흐름(stream)이므로 정부의 인위적인 개입의 여지가 적기 때문이다. The goal of this study is to explore the chronological change of Korean standardization and standards policies within a political economy framework by analyzing the cross-correlation between R&D (Research and Development) expenditures and the number of international standards, suggested to IEC (International Electrotechnical Commission) in ICT (Information and Communications Technology). During the last 16 years, South Korea has financially and systemically supported the ICT industry for economic growth so as to become a market leader in the high-tech industry in the world. To explore whether the government investments would increase the number of international standards suggested to IEC as an alternative to take a market leader position, we used a cross-correlation function. The results of the analysis show that there is a positive association between R&D investments and the number of international standards to IEC at the time lag 1 and 0 from 2003 to 2017. Meanwhile, the size of R&D investments has gradually increased in the study period, but the increase of international standards suggested to IEC became moderated when the government started to privatize standardization processes. This finding indicates that the government intervention and supports could play an important role to increase the number of international standards upon the assumption that three key factors; technical development, mature market, and government supports need to come together in order for a country to have more international standards. It is because that the technical development and mature market are the streams governments could not get directly involved due to international law and free trade agreements.

Examining Spatial Associations of Road Intersections, Traffic Accidents, and Health Facilities in Lagos, Nigeria

김형아(HyoungAh Kim) 위기관리 이론과 실천 2020 Crisisonomy Vol.16 No.3

아프리카 등 제3세계 국가와 같이 사회 인프라가 낮은 지역은 데이터 및 연구시설의 부족으로 증거기반(evidence-based) 교통안전 정책 마련에 어려움을 겪기가 쉽다. 특히 저개발 국가일수록 재정적어려움으로 인해 선진국보다 더 효율적인 방법을 사용하여 안전시설을 배치해야 하는데, 교통사고위치와 같은 중요데이터가 없는 경우가 많아 안전시설의 과학적 배치가 어려운 실정이다. 이 논문은저개발 국가를 위해, 교통안전 정책마련 시 도로의 교차점을 사고다발지역으로 가정하고 핫스팟분석(Hotspot analysis)을 통해 사고 위험성이 높은 지역을 유추한 후 교통안전시설 배치를 위한 방법을 제안하는 데 목적이 있다. 나이지리아의 라고스(Lagos) 주를 연구대상으로 계산한 결과 도로교차점과 사고 수가 통계적으로 상관관계가 높다는 사실 및 도시지역이 비도시 지역보다 사고의 수가많지만, 사고의 심각성(severity)은 낮다는 사실을 밝혀냈다. 이 논문에서 제안한 방법이 다른 아프리카 도시 및 지역에도 확대·적용되어 도로 안전 수준을 높이는 데 기여하길 바란다. The purpose of this study is to suggest a new method to estimate the potential hotspots of road traffic accidents (RTAs) in underdeveloped countries. Due to the lack of infrastructure and experiences, many underdeveloped countries have failed to prepare effective policies to reduce traffic accidents. Considering their fiscal constraints, it would be critical to allocate health and traffic safety facilities with evidence-based methods. This study suggests the method of using road intersections as potential high-risk areas of RTAs when no accurate data are available in underdeveloped countries. Using the data from Lagos State in Nigeria, RTA hotspots were identified based on road intersections and travel distances from the high-risk points to the nearest health facility were calculated. There was a strong spatial correlation between the number of road traffic accidents and road interactions (<0.001). It is also found that urban areas had more traffic accidents but crashes were less severe, compared to suburban areas. These results indicate a disproportional allocation of health facilities between urban and suburban areas in Lagos, Nigeria.

소방공무원의 스트레스 관리정책 개선을 위한 연구

김형아(HyoungAh Kim),한재호(Jaeho Han),황선규(Sungyu Hwang),장재혁(Jaehyeok Jang),강동민(Dongmin Kang) 한국방재학회 2024 한국방재학회논문집 Vol.24 No.1

Assessment of skin sensitization potential of manganese oxide and copper oxide nanoparticles through the local lymph node assay: 5-Bromo-deoxyuridine flow cytometry method

Ravi Gautam,DaEun Lee,Anju Maharjan,Manju Acharya,JiHun Jo,HyunJi Park,YuBin Kim,Pramod Bahadur KC,Chang Yul Kim,HyoungAh Kim,JiMin Choi,SooMin Lim,YoungWoo Shin,SuBin Yang,Yong Heo 한국실험동물학회 2021 한국실험동물학회 학술발표대회 논문집 Vol.2021 No.7

Nanoparticles (NPs), fine particles ranging from 1 to 100 nm, are being used extensively in various fields including industry, agriculture, engineering. Nanoparticles also have become the imperative parts of cosmetic and dermal products owing to the higher benefits over their counter bulk particles. Manganese oxide (Mn2O3) and copper oxide (CuO) are used in cosmetics and dermal products owing to their UV protection and antimicrobial properties and also to make products transparent and aesthetically acceptable. Although Mn2O3 and CuO are used in consumer products that get exposed to the skin, their skin sensitization potential has not been well investigated. In this study we employed, Local lymph node assay: 5-bromo-2-deoxyuridine-flow cytometry method (LLNA: BrdU-FCM) to predict the skin sensitization (SS) potential of nanoparticles. LLNA: BrdU-FCM is a method for screening of SS potential that addressed the activation and proliferation of T-lymphocytes, key event-4 (KE-4), on adverse outcome pathway (AOP) for SS. Mn2O3 (5%, 10%, and 25%), and CuO (5%, 10%, and 25 %) NPs were suspended in dimethyl sulfoxide (DMSO) for experimentation. AOO (acetone: olive oil = 4:1) and α-hexyl cinnamaldehyde were used as negative and positive control respectively. Mn2O3 and CuO NPs were both classified as non-sensitizer with maximum stimulation indices of 1.4 and 0.99 respectively. Although both NPs were classified as non-sensitizer using LLNA: BrdU-FCM, further assays addressing other KEs of AOP for SS could be carried out as confirmation and cautious use of products containing these nanoparticles is recommended as various studies have revealed their toxicity in vitro . This study was supported by the Korea National Research Foundation (grant number: 2020R1I1A3A0403650911) and the Ministry of Environment-Educational training program for the management of information on the hazards and risk of chemical substances.

Quantitative Association of Humoral or Cellular Immunologic Markers with the Prediction of Skewed Adaptive Immunity in Agricultural Workers

Anju Maharjan,JiHun Jo,Manju Acharya,SuJeong Yang,Ravi Gautam,Sojung Sin,Hyocher Kim,ChangYul Kim,Yong Heo,HyoungAh Kim 계명대학교 자연과학연구소 2020 Quantitative Bio-Science Vol.39 No.2

The paradigm of immune homeostasis between type-1 helper T cells (Th1) and type-2 helper T cells (Th2) has been extensively examined with respect to infectious diseases, autoimmune diseases, or tumor progression. Such studies have mostly relied on the profiling of cytokines/chemokines using animal studies or cell culture-based in vitro tests. No quantitative analyses have yet been systematically performed to determine the relationship between the various immune parameters in in vivo investigations. Using peripheral blood from 55 chicken husbandry workers or grapevine orchard workers, we obtained data for various immunologic markers as follows: proportion of major immune cell subpopulations, concentrations of plasma immunoglobulin subclasses, and levels of cytokines produced from activated peripheral blood mononuclear cells. Correlational analyses were carried out to examine the association between these parameters. As the IFN-γ:IL-13 ratio was strongly associated with the production levels of IFN-γ, TNF-α, and to the IFN-γ:IL-4 ratio, the IFN-γ:IL-13 ratio could prove to be a valuable monitoring index to examine Th1 or Th2 predominance. IL-17 levels correlated well with those of IFN-γ or TNF-α. Plasma levels of IgG4, a typical IgG subclass expressed upon the occurrence of allergic diseases, strongly correlated with IgG1 levels, suggesting the implication of IgG1 in allergic hyperreactivity. The proportion of cytotoxic T cells correlated significantly with levels of IFN-γ, and the proportion of natural killer T cells correlated well with IL-13 levels. These two cell types are sources for the production of IFN-γ and IL-3 respectively; hence, results of this study might provide potential monitoring markers for cytotoxic T cells or natural killer T cell-mediated immunoreactivity. Overall, the present study provides several putative candidates for the surveillance or prognosis of the in vivo alteration of humoral or cell-mediated immunity.

Comparison of Overall Immunity Levels among Workers at Grape Orchard, Rose Greenhouse, and Open-Field Onion Farm

Maharjan, Anju,Gautam, Ravi,Jo, JiHun,Acharya, Manju,Lee, DaEun,Pramod, Bahadur KC,Gim, Jin,Sin, Sojung,Kim, Hyocher,Kim, ChangYul,Lee, SooYeon,Lee, SooJin,Heo, Yong,Kim, HyoungAh Occupational Safety and Health Research Institute 2022 Safety and health at work Vol.13 No.2

Background: Occupational hazards in crop farms vary diversely based on different field operations as soil management, harvesting processes, pesticide, or fertilizer application. We aimed at evaluating the immunological status of crop farmers, as limited systematic investigations on immune alteration involved with crop farming have been reported yet. Methods: Immunological parameters including plasma immunoglobulin level, major peripheral immune cells distribution, and level of cytokine production from activated T cell were conducted. Nineteen grape orchard, 48 onion open-field, and 21 rose greenhouse farmers were participated. Results: Significantly low proportion of natural killer (NK) cell, a core cell for innate immunity, was revealed in the grape farmers (19.8±3.3%) in comparison to the onion farmers (26.4±3.1%) and the rose farmers (26.9±2.5%), whereas cytotoxic T lymphocyte proportion was lower in the grape and the onion farmers than the rose farmers. The proportion of NKT cell, an immune cell implicated with allergic response, was significantly higher in the grape (2.3±0.3%) and the onion (1.6±0.8%) farmers compared with the rose farmers (1.0±0.4%). A significantly decreased interferon-gamma:interleukin-13 ratio was observed from ex vivo stimulated peripheral blood mononuclear cells of grape farmers compared with the other two groups. The grape farmers revealed the lowest levels of plasma IgG1 and IgG4, and their plasma IgE level was not significantly different from that of the onion or the rose farmers. Conclusion: Our finding suggests the high vulnerability of workplace-mediated allergic immunity in grape orchard farmers followed by open-field onion farmers and then the rose greenhouse farmers.

Prediction of skin sensitization potential of silicon dioxide and titanium dioxide nanoparticles through the local lymph node assay: 5-bromo-2-deoxyuridine flow cytometry method

Manisha Adhikari,Ravi Gautam,Manju Acharya,Anju Maharjan,DaEun Lee,JiSun Lee,JinHo Kim,MinHee Kim,GiYong Lee,Chang Yul kim,HyoungAh Kim,Yong Heo 한국실험동물학회 2022 한국실험동물학회 학술발표대회 논문집 Vol.2022 No.7

Immunodysregulatory potentials of polyethylene or polytetrafluorethylene microplastics to mice subacutely exposed via intragastric intubation

Jo JiHun,Acharya Manju,K C Pramod Bahadur,Maharjan Anju,Lee DaEun,Gautam Ravi,Kwon Jung-Taek,Kim KilSoo,Kim ChangYul,Heo Yong,Kim HyoungAh 한국독성학회 2023 Toxicological Research Vol.39 No.3

Microplastics (MPs) have been recently recognized as posing a risk to human health. The adverse health effects of MP exposure have been recently reported, especially via the oral exposure route. The present study investigated whether subacute (4 week) exposure to polyethylene (PE) or polytetrafluorethylene (PTFE) MPs via gastric intubation caused immunotoxicity. Two different sizes of PE MPs (6.2 or 27.2 μm) and PTFE MPs (6.0 or 30.5 μm) were administered to 6-week-old mice of both sexes at 0 (corn oil vehicle control), 500, 1000, or 2000 mg/kg/day (n = 4/group). No significant differences were observed between groups in the major thymic or splenic immune cell populations, including thymic CD4+, CD8+, CD4+/ CD8+ T lymphocytes, and splenic helper T cells, cytotoxic T cells, and B cells. The ratio of interferon-gamma (IFNγ) to interleukin-4 (IL-4) in culture supernatants from polyclonally activated splenic mononuclear cells ex vivo (48 h) was dosedependently decreased in female mice that received small- and large-size PTFE MPs. The IFNγ/IL-4 ratio was also decreased in the female mice dosed with large-size PE MPs. The serum IgG2a/IgG1 ratio was dose-dependently increased in male and female animals dosed with small-size PE MPs, in female animals dosed with large-size PTFE MPs, and in male animals dosed with small-size PTFE MPs. The present study implies that immune functions could be affected in animals exposed to MPs via gastric intubation. These effects are dependent on MP size, MP dose, MP polymer type, and mouse sex. Further investigations with longer exposure periods could be necessary to more clearly define the immunotoxic effects of MPs.