Installation of the Brackish Water Reverse Osmosis System Coupled with Solar Power for Drinking Water Production in Ben Tre, Vietnam Considering Water Usage and Cost

Seongpil Jeong(Seongpil Jeong),Hye-Won Kim(Hye-Won Kim),Kyungjin Cho(Kyungjin Cho),Dongjin Yang(Dongjin Yang),Seong-Rae Kim(Seong-Rae Kim),Soon-Ho Park(Soon-Ho Park) 적정기술학회 2022 적정기술학회지(Journal of Appropriate Technology) Vol.8 No.2

Recently, the unbalanced water demand and supply have been occurred globally due to the climate change, industrialization, and population increase. The water shortage problem became much severe in the developing countries because the low-stage of infrastructure might result in frequent limitation of water and transportation of water. Therefore, sustainable water supplying option is the key for the boosting the local economy. The Mekong Delta area produce most of the products in agriculture and fishery in Vietnam. However, due to low income and vast area, the infrastructure for water supply has been limited in the Mekong Delta area. Moreover, due to reduced Mekong-river flow by the dam construction in upper reaches, increased seawater level by the global warming, and increased unexpected drought and flooding by the climate change, the water supply in the Mekong delta is becoming hard. Therefore, sustainable water supplying option was required. In this study, the reverse osmosis-based desalination process could use undrinkable saline water as the feed water coupled with photovoltaic panel was suggested. In order to install the decentralized and off-grid type water production plant in the proper place in the Mekong Delta, the KIST, VKIST, and central and local governments in Vietnam collaborated. The RO plant could be successfully installed by the help of the partners and the operational conditions have been monitored. If the water providing option could be separated according to the purposes such as drinking usage and other water usage, the more technical options could be applied for the water production.

Effect of engineered environment on microbial community structure in biofilter and biofilm on reverse osmosis membrane

Jeong, Sanghyun,Cho, Kyungjin,Jeong, Dawoon,Lee, Seockheon,Leiknes, TorOve,Vigneswaran, Saravanamuthu,Bae, Hyokwan Pergamon Press 2017 Water research Vol.124 No.-

<P><B>Abstract</B></P> <P>Four dual media filters (DMFs) were operated in a biofiltration mode with different engineered environments (DMF I and II: coagulation with/without acidification and DMF III and IV: without/with chlorination). Designed biofilm enrichment reactors (BERs) containing the removable reverse osmosis (RO) coupons, were connected at the end of the DMFs in parallel to analyze the biofilm on the RO membrane by DMF effluents. Filtration performances were evaluated in terms of dissolved organic carbon (DOC) and assimilable organic carbon (AOC). Organic foulants on the RO membrane were also quantified and fractionized. The bacterial community structures in liquid (seawater and effluent) and biofilm (DMF and RO) samples were analyzed using 454-pyrosequencing. The DMF IV fed with the chlorinated seawater demonstrated the highest reductions of DOC including LMW-N as well as AOC among the other DMFs. The DMF IV was also effective in reducing organic foulants on the RO membrane surface. The bacterial community structure was grouped according to the sample phase (i.e., liquid and biofilm samples), sampling location (i.e., DMF and RO samples), and chlorination (chlorinated and non-chlorinated samples). In particular, the biofilm community in the DMF IV differed from the other DMF treatments, suggesting that chlorination exerted as stronger selective pressure than pH adjustment or coagulation on the biofilm community. In the DMF IV, several chemoorganotrophic chlorine-resistant biofilm-forming bacteria such as <I>Hyphomonas</I>, <I>Erythrobacter</I>, and <I>Sphingomonas</I> were predominant, and they may enhance organic carbon degradation efficiency. Diverse halophilic or halotolerant organic degraders were also found in other DMFs (i.e., DMF I, II, and III). Various kinds of dominant biofilm-forming bacteria were also investigated in RO membrane samples; the results provided possible candidates that cause biofouling when DMF process is applied as the pretreatment option for the RO process.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Four dual media filters (DMFs) were operated under different engineered conditions. </LI> <LI> DMF with pre-chlorination treatment was effective to reduce organic matter. </LI> <LI> Functional biofilm bacterial structure in DMF and RO membranes were investigated. </LI> <LI> Pre-chlorination acted stronger selective pressure on biofilm community. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Korea Brain Initiative: Emerging Issues and Institutionalization of Neuroethics

Jeong, Sung-Jin,Lee, In Young,Jun, Bang Ook,Ryu, Young-Joon,Sohn, Jeong-woo,Kim, Sung-Phil,Woo, Choong-Wan,Koo, Ja Wook,Cho, Il-Joo,Oh, Uhtaek,Kim, Kyungjin,Suh, Pann-Ghill Elsevier 2019 Neuron Vol.101 No.3

<P>Neuroscience research has become a national priority for the Korean government. Korean scholars have dedicated interest in the societal ramifications of neurotechnologies; neuroethics is an integral component of the Korea Brain Initiative and to the formation of its growing neuroscience community.</P>

Current technologies on ultrapure water production: based on the patent survey

Seongpil Jeong,Hyokwan Bae,Kyungjin Cho,Minkyu Choi,Seungheon Yang,Dawon Jeong,Taekgeun Yun,Heoncheol Koo,Seokcheon Lee 대한환경공학회 2015 대한환경공학회 학술발표논문집 Vol.2015 No.10

상이한 아이템에 대한 사용자 선호도 활용 LOCA 접근 방법 연구

백주련(Juryon Paik),고광호(Kwang-Ho Ko) 한국컴퓨터정보학회 2022 한국컴퓨터정보학회 학술발표논문집 Vol.30 No.2

보육교사 소진과 극복 경험에 대한 질적 메타분석

정경진(Jeong, Kyungjin),윤혜미(Yoon, Hyemee) 한국영유아보육학회 2024 한국영유아보육학 Vol.- No.147

본 연구의 목적은 보육교사의 소진경험과 극복과정을 다룬 질적 연구들을 질적 메타분석 유형 중 질적 연구 종합(QRS:qualitative research synthesis) 방법을 이용하여 분석함으로써 공통적 주제와 패턴을 제시하고 개별 연구 결과를 넘어선 새로운 통찰과 해석을 도출하고자 하는 것이다. 자료수집은 학술 DB 등을 검색하여 2023년까지 발표된 총 15편 중 8편을 최종 선정하였고 이 과정에서 CASP(Critical Appaisal Skill Programme)을 적용하여 연구물의 질을 평가하였다. 분석결과, 총 53개의 기술적 주제를 2차적으로 종합하여 새로운 해석의 가능성을 보여주는 13개의 종합적 주제로 추출한 후‘다양한 스트레스로 지쳐감, ‘소진 증상을 겪게 됨’, ‘치유와 회복을 위한 노력’, ‘소진 극복으로 개인적•전문적 성장’ 이라는 4개의 핵심주제를 도출했다. 소진을 유발하는 다양한 스트레스는 심리적 요인, 직무요인, 조직요인으로 분류할 수 있었고, 소진증상으로는 정서적 고갈, 부정적 정서 반응, 대인관계 철회 및 소극적 직무수행라고 하는 소진의 하위구조들을 공유하는 것으로 나타났다. 특징적으로 연구물간 구조관계에서는 소진과정을 다룬 기존연구들과 달리 질적 연구물에서는 치유와 회복과정이 심도있게 논의되어 소진 극복 후 성장이라는 핵심 주제가 드러나 차별화되었다. 질적 메타분석을 통해 소진의 치유와 회복, 성장 경험이 연구참여 보육교사들에게 의미있게 도출되어 앞으로의 소진 연구가 가야 할 방향을 시사하고 있다. This study systematically synthesizes qualitative research on experiences of burnout and coping process among childcare teachers, aiming to identify common themes and patterns. The research involved a comprehensive search of academic databases, resulting in the selection of eight relevant qualitative studies published up to 2023, which were evaluated for quality using the Critical Appraisal Skills Programme (CASP). Through detailed analysis, 13 comprehensive themes were extracted from 53 technical topics, revealing new interpretive possibilities. Four core themes emerged: Exhaustion from Various Stressors, Experience of Burnout Symptoms, Pursuit of Healing and Recovery, and Personal and Professional Growth. Common stressors precipitating burnout were identified across psychological, job-related, and organizational dimensions, with burnout symptoms including emotional exhaustion, depersonalization, and lack of personal accomplishment. A distinctive contribution of this study is the identification of growth following burnout coping, which extends beyond the traditional focus on the burnout process itself. The findings underscore the importance of healing, recovery, and growth, offering new directions for future research on burnout among childcare teachers.

Suppressive Mechanism of Platycodi Radix in B16F10 Melanoma Cell Metastasis

Jeong HyeGwang,Lee KyungJin 大韓藥學會 2003 大韓藥學會 總會 및 學術大會 Vol.2003 No.1

Effects of salinity on nitrification efficiency and bacterial community structure in a nitrifying osmotic membrane bioreactor

Jeong, Dawoon,Cho, Kyungjin,Lee, Chang-Ha,Lee, Seockheon,Bae, Hyokwan Elsevier 2018 PROCESS BIOCHEMISTRY Vol.73 No.-

<P><B>Abstract</B></P> <P>The objective of this study was to evaluate the effects of salt accumulation on nitrifying bacterial communities in a nitrifying bioreactor combined with forward osmosis. The conversion of nitrite to nitrate was inhibited at a total dissolved solids (TDS) concentration of 17.3 g/L, whereas conversion of ammonia to nitrite was inhibited at a higher concentration (52.8 g-TDS/L). The gene copies of ammonia-oxidizing bacteria (AOB) were more abundant than those of nitrite-oxidizing bacteria (NOB) throughout the entire operating period of 225 days. Among NOB, the number of copies of <I>Nitrobacter</I> spp. were 100–1000 times higher than those of <I>Nitrospira</I> spp. A total of 140 operational taxonomic units were identified using 454 pyrosequencing. The relative abundances of autotrophic AOB and NOB accounted for 34.1–57.8% during 225 days. Dominance of <I>Nitrosomonas eutropha</I> was stable as a salt-tolerant AOB, but the representative NOB, <I>Nitrobacter winogradskyi</I>, showed salt-sensitive variations in their relative abundance. Nonmetric multidimensional scaling and hierarchical clustering analysis clearly illustrated the shift in bacterial community due to external conditions, i.e., ammonia loading rate, alkalinity availability, and salinity. Heterotrophic bacteria contributed to changes in overall bacterial community structure in the nitrifying osmotic membrane bioreactor despite the absence of carbon sources in the influent.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Bacterial population dynamics were studied in an osmotic membrane bioreactor. </LI> <LI> Ammonia, alkalinity, and salinity caused changes in the bacterial community. </LI> <LI> Increased salinity led to NOB activity inhibition at 17.3 g-TDS/L. </LI> <LI> AOB were more tolerant than NOB to the high ammonia-loading rate and salinity. </LI> <LI> <I>Nitrosomonas eutropha</I> was dominant at high ammonia and salt concentrations. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Evaluating the feasibility of pyrophyllite-based ceramic membranes for treating domestic wastewater in anaerobic ceramic membrane bioreactors

Jeong, Yeongmi,Cho, Kyungjin,Kwon, Eilhann E.,Tsang, Yiu Fai,Rinklebe, Jö,rg,Park, Chanhyuk Elsevier 2017 Chemical engineering journal Vol.328 No.-

<P><B>Abstract</B></P> <P>This study laid great emphasis on anaerobic ceramic membrane bioreactor (AnCMBR) treatment of domestic wastewater for facile and enhanced energy recovery. To this end, the performance of the natural-based ceramic (<I>i.e.</I>, pyrophyllite-based) membranes was mainly explored in this study by evaluating filtration and treatment performances. 92.9±5.5% chemical oxygen demand (COD) removal and stable methane production were successfully achieved in a bench-scale AnCMBR while maintaining a slightly long hydraulic retention time (HRT). Comparative filtration experiments with commercialized ceramic membranes suggested that the pyrophyllite-based membrane separation in AnCMBR treatment of wastewater at long HRT is feasible. However, short HRT operations resulted in substantial levels of sludge washout. Future improvements of AnCMBR technology in cost-effective ceramic membrane development, increased flux, and harsh environmental conditions would make AnCMBR competitive with anaerobic membrane bioreactor (AnMBR) technology.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Pyrophyllite-based ceramic membranes applied to anaerobic membrane bioreactors. </LI> <LI> This novel approach achieved higher organic removal and methane yield at long HRTs. </LI> <LI> Short HRT operations resulted in substantial levels of sludge washout. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Effects of Platycodi Radix on Hepatic Fibrosis in Rats

Jeong HyeGwang,Cho YoungSoo,Choi ChulYung,Chung YoungChul,Ryu SiYung,Kim YoungSup,Lee KyungJin 大韓藥學會 2003 大韓藥學會 總會 및 學術大會 Vol.2003 No.1