배치 실험을 이용한 암모니아 제거 기작 및 효율 평가

장지은,강지영,김혜원,신규진,진성욱,Jang, Jieun,Kang, Jiyoung,Kim, Hye Won,Shin, Kyu Jin,Jeen, Sung-Wook 한국지하수토양환경학회 2022 지하수토양환경 Vol.27 No.6

As the amount of livestock wastewater increases, ammonia contamination in surface water and groundwater is also increasing, and its treatment is urgently needed. In this study, indigenous soil bacteria was utilized for ammonia removal in artificial wastewater and associated removal mechanisms and efficiencies were evaluated. Two batch reactors were configurated to contain natural soil and artificial wastewater at 1:10 mass ratio, and incubated for 84 and 168 hours, respectively. The results showed that ammonia was completely removed within 48 and 72 hours in the first and second reactors, respectively. There were no significant changes in ammonia concentrations in the control groups without soil. Nitrate was formed in the reactors, indicating that the main removal mechanism of ammonia was nitrification by nitrifying bacteria. Nitrate was further converted to nitrogen gas by denitrification in the anaerobic environment, which was caused by consumption of oxygen during the nitrification process.

공중재급유를 위한 상대운동방정식 유도 및 검증

장지은,이상종,유혁,Jang, Jieun,Lee, Sangjong,Ryu, Hyuk 한국항공운항학회 2013 한국항공운항학회지 Vol.21 No.4

This paper addresses the derivation of 6-DOF equation of Tanker and Receiver's aircraft for aerial refueling. The new set of nonlinear equations are derived in terms of the relative translational and rotational motion of receiver aircraft respect to the tanker aircraft body frame. Further the wind effect terms due to the tanker's turbulence are included. The derivation of absolute dynamic equation for tanker aircraft written in the inertial frame is calculated from the relative dynamics equations of receiver. The derived relative and absolute equations are implemented the simulation in the same flight conditions to verify the relative motion and compare the trim results by using the MATLAB/SIMULINK program.

개인의 사회경제적 수준과 지역의 사회경제적 수준의 상호작용이 제2형 당뇨 환자에서 당뇨합병증 발생 및 당뇨와 관련된 입원에 미치는 영향: 2002-2013년 국민건강보험공단 표본 코호트 자료를 활용하여

장지은 ( Jieun Jang ),주영준 ( Yeong Jun Ju ),이두웅 ( Doo Woong Lee ),이상아 ( Sang Ah Lee ),오소연 ( Sarah Soyeon Oh ),최동우 ( Dong-woo Choi ),이현지 ( Hyeon Ji Lee ),신재용 ( Jaeyong Shin ) 한국보건행정학회 2021 보건행정학회지 Vol.31 No.1

Background: In this study, we aimed to investigate the interaction effects of individual socioeconomic status and regional deprivation on the onset of diabetes complications and diabetes-related hospitalization among type 2 diabetes patients. Methods: Korean National Health Insurance Service National Sample Cohort data from 2002 to 2013 were used. A total of 50,954 patients newly diagnosed with type 2 diabetes from 2004 to 2012 and aged 30 years or above were included. We classified patients into six groups according to individual income level and neighborhood deprivation: ‘high in advantaged,’ ‘high in disadvantaged,’ ‘middle in advantaged,’ ‘middle in disadvantaged,’ ‘low in advantaged,’ and ‘low in disadvantaged.’ We calculated hazard ratios (HR) of onset of diabetes complication and diabetes-related hospitalization using the Cox proportional hazard model, with the reference group as diabetes patients with high income in advantaged regions. Results: In terms of the interaction effects of individual income level and regional socioeconomic level, even with the same low individual income level, the group with a high regional socioeconomic level (low in advantaged) showed low HRs for the onset of diabetes complication (HR, 1.04; 95% confidence interval [CI], 1.00-1.08) compared to the ‘low in disadvantaged’ group (HR, 1.10; 95% CI, 1.05-1.16). In addition, the ‘high in advantaged’ group showed slightly higher HRs for the onset of diabetes complication (HR, 1.06; 95% CI, 1.00-1.11) compared to the ‘low in advantaged’ and it appeared to be associated with slight mitigation of the risk of diabetes complication. For the low-income level, the patients in disadvantaged regions showed the highest HRs for diabetes-related hospitalization (HR, 1.29; 95% CI, 1.19-1.41) compared to the other groups. Conclusion: Although we need to perform further investigations to reveal the mechanisms that led to our results, interaction effects individual socioeconomic status and regional deprivation might be associated with on onset of diabetes complications and diabetes-related hospitalization among type 2 diabetes patients.

대황으로부터 세균성 질염 치료를 위한 항균성 물질의 분리 및 특성

장지은(Jieun Jang),강동희(Dong-Hee Kang),윤재우(Jaewoo Yoon),김현수(Hyun-Soo Kim) 한국생물공학회 2017 KSBB Journal Vol.32 No.2

Rheum palmatum has traditionally been used as a preventive agent and medication against fever and infection. The aim of this study was to isolate and characterize an antibacterial substance from R. palmatum that is effective against bacterial vaginosis. A methanol extract from R. palmatum showed antibacterial activity against Lactobacillus vaginalis KC TC 3515, Chryseobacterium gleum KCTC 2904, and Sphingomonas paucimobilis KCTC 2834, which cause bacterial vaginosis. After extraction and pH control of the methanol extract from R. palmatum, we found that acidic and alkaline extracts did not show antibacterial activity. A neutral extract (50 mg/mL) displayed an inhibitory zone of 18 mm on a nutrient agar plate with C. gleum KCTC 2904. Fractions No. 11 and 12 among 41 fractions obtained by silica gel column chromatography produced inhibitory zones of 10 mm on nutrient agar plates with C. gleum KCTC 2904. Rf0.15 and Rf0.17 spots produced by TLC of fraction No. 11 showed antibacterial activity against C. gleum KCTC 2904. Isolation and purification of the peak at a retention time (Rt) of 9.427 min was achieved by HPLC of Rf0.29spots. The peak at Rt 9.427 min showed antibacterial activity against C. gleum KCTC 2904.

사물인터넷을 위한 퍼지 로직 기반 클러스터링 알고리즘

장지은(Jieun Jang),이휘호(Hwi-Ho Lee),오하라(Ha-Ra Oh),권정혁(Jung-Hyok Kwon),김의직(Eui-Jik Kim) 한국통신학회 2016 한국통신학회 학술대회논문집 Vol.2016 No.6

노년기의 성공적 노화와 취로 활동 : 일본의 오가와노쇼 오야키무라 사례를 중심으로

장지은(Jang JiEun) 한국비교교육학회 2017 比較敎育硏究 Vol.27 No.3

본 논문은 고령자의 사회참여의 일 형식으로서 경제활동에 대한 대안적 인식의 필요성과 이에 따른 고령자 교육의 과제를 제기하기 위하여 추진되었다. 이를 위하여 일본의 ‘보람 취로’의 개념과 실천사례를 고찰하였다. 문헌연구를 통하여 일본의 국가 및 지자체의 고령자정책사업을 개관하는 가운데 그 특징을 살피어 보았다. 그리고 고령자들이 자주적인 회사설립을 통하여 추진한 사례, 오가와 노쇼 오야키무라의 실천을 현지방문과 인터뷰조사를 통하여 고찰하였다. 본 연구를 통하여 얻은 결과는 다음과 같다. 고령자의 경제활동은 성공적 노화의 관점에서 전개되어야 할 필요가 있고 이러한 경제활동은, 일본의 ‘보람취로’에서와 같이 다음과 같은 특징을 가진다. 첫째, 고령자상에 대한 변화된 인식이 필요하다. 고령자는 사회적 활용의 가치가 있는 경험자원을 가진 존재이다. 둘째, 고령자가 가진 경험자원을 사회적 가치로 창조하여 내는 교육과 기관경영이 필요하다. 셋째, 노년기에 부합한 일에 대한 유연한 인식이 필요하다. 즉 노년기의 심리적 고독경향, 사회적 단절 특성을 반영하고 이외에도 의미있는 존재가 되고 싶은 노년기의 요구를 반영한 일의 고안이 필요하다. 그러므로 향후 고령자 교육은 보람취로의 관점에서 일 교육에 대한 방침과 실천을 고안할 필요가 있다. The purpose of this study is to raise the necessity of an alternative awareness toward economic activities as the work form of social participation by the elderly and their corresponding educational tasks. For this aim, the concept of Japan’s ‘rewarding work participation’ and its practical cases have been examined. As a study method, the characteristics of Japan’s state and local government elderly policy projects have been examined through literature research. Next, the cases of the elderly having established an autonomous company and practiced Ogawanosho Oyakimura were researched based on on-site visits and interviews. As this study has suggested that the economic activities of the elderly have to be carried out from the perspective of successful aging and these activities have been conducted through ‘rewarding work participation’, the following features have been clarified. First, a converted image of the elderly is necessary. The elderly do have the experiences worthy of social utilization. Second, the educational and managerial policies which turn the elderly’s experiences into social values are necessary. Third, a flexible awareness toward the corresponding works of the elderly is needed. In other words, the works which have reflected mentally solitary tendency and social discontinuity features of the elderly and taken into account the demands of the elderly generation who desire to become an influential and meaningful existence are necessary. Thus, future elderly education need to come up with the policies and practices toward work education from the viewpoint of rewarding work participation.

가상 상대방(agent)의 프로필 외모 유사성 효과 연구

주연경(Yeon Kyoung Joo),김경보(Kyungbo Kim),장지은(Jieun Jang),장지호(Jiho Jang),심효주(Hyoju Shim),제갈성경(Sunggyung Jegal),허재원(Jaewon Hur) 사이버커뮤니케이션학회 2016 사이버 커뮤니케이션 학보 Vol.33 No.2

사람들이 자신과 유사한 존재에 대해 본질적으로 호감을 느낀다는 것은 잘 알려진 심리학적 사실이다. 이렇듯 비슷한 상대방에게 끌린다는 것을 나타내는 유사성 효과라고 부른다. 유사성 효과는 대인 커뮤니케이션뿐만 아니라, 인간 컴퓨터 상호작용의 맥락에서도 종종 관찰된다. 사용자들이 자신과 유사한 가상 상대방에게 더 호감을 느끼는 것이 바로 그것이다. 이런 유사성 효과는 사용자와 가상 상대방이 갈등 관계에 놓인 이후에도 지속될 수 있을까? 본 연구는 유사성 효과가 가상 상대방과의 갈등 경험 후에도 계속 이어질 수 있는지 실험 연구를 통해 살펴보았다. 더불어 본 연구는 갈등 상황 시, 가상 상대방과 사용자간의 개인 정보 프로필의 유사성과 외모 유사성이 갈등적 상황에서의 경쟁 전략 선택에 어떤 영향을 끼칠지 살펴보았다. 이를 위해 총 80여명의 실험 참가자가 가상 상대방과 온라인으로 최후통첩게임이라는 경쟁적인 협상 과제를 수행하였다. 실험 참가자들은 각각 자신과 유사하거나 유사하지 않은 가상 사용자와 함께 상호작용을 하였다. 이를 위해 2(프로필 유사도: 유사 혹은 상이)x 2(외모 유사도: 유사 혹은 상이)요인 설계가 제공되었다. 실험 결과, 다음과 같은 결과를 얻었다. 우선, 사용자들은 초기에는 자신과 프로필이나 외모가 유사한 가상 상대방에게 호감을 보였다. 그러나 경쟁적 게임이 시작되자, 실험 참가자들은 오히려 자신과 유사한 상대방에게 이기적인 전략을 취하였다. 특히 게임이 반복됨에 따라 외모가 유사한 상대방에게 이기적인 전략을 취하는 태도가 도드라졌다. 게임이 끝나고 이어진 경험 평가에서, 실험 참가자들은 다른 외모를 가진 상대방과 갈등적 상황에 놓인 경험보다 외모가 유사한 상대방과 갈등적 상황에 놓인 경험을 더욱 부정적으로 평가했다. 이와 관련된 시사점 및 한계점이 논의되었다. It is well known that people are likely to be prone to similar others. This phenomenon is referred to as similarity effect. Similarity effect has been found in a variety of domains, including both humanhuman interaction and human-computer interaction. Recent studies showed that users are likely to have positive experiences when they are interacting with agents or avatars that are similar to the users. The current study explored if this positive experience based on similarity between users and agents can last even after users’ performing a series of competitive tasks against the similar agent. Furthermore, the current study investigated how profile/face similarity of the agent would influence users’ strategies at the competitive tasks. We recruited 80 participants and randomly assigned them to one of four experimental conditions based on a 2(agent’s profile: similar/ dissimilar) x 2(agent’s face: similar/dissimilar) factorial design. Participants played a series of competitive economic games, the ultimatum game, with a similar or dissimilar virtual agent. The findings of the current study showed that both profile similarity and face similarity were effective to formulate positive first impression about the agent. However, similarity was found to lead to selfishness at the game; participants took more selfish strategies when they were interacting with the agents that were similar to them, compared to the agents that were dissimilar. Moreover, participants reported that they felt more negative when they were interacting with the agent with a similar face. Implications of the findings are discussed.

일반화된 무인항공기 선회 유도법칙 설계

문정호(Jungho Moon),박종근(Jonggeun Park),장지은(Jieun Jang),박문수(Munsoo Park) 한국항공우주학회 2016 한국항공우주학회 학술발표회 논문집 Vol.2016 No.4

오픈폼을 이용한 120W급 동축반전 축류팬에 대한 수치해석 연구

이명성(Myungsung Lee),정윤주(Yoonju Jung),장지은(Jieun Jang),김주한(Joo-Han Kim) 대한기계학회 2016 대한기계학회 춘추학술대회 Vol.2016 No.12

Due to the restriction of energy consumption and requirement of product size, a compact axial fan is highly demanded in various industrial fields. The counter-rotating axial fan could be a promising way to achieve these demands with decreasing rotational speed and increasing axial speed for the flow downstream of the fan. The present paper deals with a numerical simulation for an 120W counter-rotating axial fan by using OpenFOAM code which is free and open numerical solvers for computational fluid dynamics. The incompressible full 3-D Navier-Stokes equation is solved with the frozen rotor method to consider the rotating motions of the front and rear rotors of the counter-rotating axial fan. The numerical results are compared to the experimental data such as static pressure rise with various air flow rate, and it shows good agreements. The results of the present study could provide useful data for optimal aerodynamic design of the counter-rotating axial fan.

곡류 및 두류를 이용한 젖산균 전배양용 식용 배지의 제조

박소림(So-Lim Park),박선현(Sunhyun Park),장지은(Jieun Jang),양혜정(Hye-Jung Yang),문성원(Sung-Won Moon),이명기(Myung-Ki Lee) 한국식품영양과학회 2013 한국식품영양과학회지 Vol.42 No.6

본 연구는 곡류 및 두류를 이용하여 식용 가능한 젖산균 모배양용 식용배지를 개발하고자 실시하였다. 식용 배지의 제조를 위하여 곡류는 발아현미, 찰현미, 발아찰현미를 사용하였고, 두류는 대두콩(대두콩, 껍질을 제거한 대두콩, 발아대두콩, 껍질을 제거한 발아 대두콩)과 검은 대두콩(검은 대두콩, 껍질을 제거한 검은 대두콩, 발아 검은 대두콩, 껍질을 제거한 발아 검은 대두콩)으로 나누어서 젖산균 증식배지를 제조하였다. 실험에 사용된 젖산균은 Lactobacillus(Lb.) farciminis, Lb. homohiochii , Lb. pentosus, Lb. plantarum, Leuconostoc(Leu.) paramesenteroides, Leu. citreum 및 Leu. lactis 총 7종이다. 곡류를 이용한 식용배지에서 배양한 경우, 7개 종균의 평균 균수는 7.6~8.0 log CFU/mL의 균수를 나타내었다. 대두콩으로 제조한 식용배지는 껍질을 제거한 발아 대두콩 배지에서 대부분의 균이 높은 증식량을 나타내었다. 특히 Lb. plantarum은 10.08 log CFU/mL로 가장 높은 균수를 보였다. 검은 대두콩의 경우는 껍질을 제거한 발아 검은 콩배지에서 증식량이 많았다. Lb. homohiochii는 껍질제거 발아 검은 콩배지에서 9.90 log CFU/mL로 가장 많은 증식량을 보였다. 모든 결과에서 곡류와 두류를 이용한 식용배지를 이용하여 배양할 때 젖산균 증균량이 우수함을 알 수 있었고, 특히 가장 증식량이 우수한 ‘껍질을 제거한 발아 검은 대두콩’ 식용 배지를 향후 젖산균 모배양에 이용하는 것을 권장한다. This study was conducted to develop an edible culture media with various types of cereals and soybeans for the pre-cultivation of lactic acid bacteria (LAB). To manufacture the edible culture media, LAB enrichment media were prepared using cereals such as brown rice (including germinated brown rice, glutinous brown rice, and germinated glutinous brown rice), yellow soybeans (including yellow soybeans, hulled yellow soybeans, germinated yellow soybeans, hulled and germinated yellow soybeans), and black soybeans (black soybeans, hulled black soybeans, germinated black soybeans, hulled and germinated black soybeans). Seven species of LAB were used in the experiment: Lactobacillus (Lb.) farciminis, Lb. homohiochii, Lb. pentosus, Lb. plantarum, Leuconostoc (Leu.) paramesenteroides, Leu. citreum, and Leu. lactis. For edible culture media from cereals, the average viable cell count of the seven starter cultures was 7.6~8.0 log CFU/mL, while that of the MRS culture medium, a synthetic medium, was 9.2 log CFU/mL; thus proliferation was lower by about 1~2 log CFU/mL in starter cultures from cereals compared to the synthetic medium. In the case of the edible culture media from soybeans, most bacteria showed higher proliferation in the hulled and germinated soybean media. In particular, Lb. plantarum showed the highest cell count at 10.08 log CFU/mL. In the case of edible culture media from black soybeans, the proliferation rate was higher in the hulled and germinated black soybean medium. Lb. homohiochii showed the highest proliferation in the hulled and germinated black soybean medium at 9.90 log CFU/mL. All results show that edible culture media using cereals and soybeans are generally good for LAB. Especially, hulled and germinated black soybeans are optimal for the pre-cultivation of LAB medium.