Transport of CO₂ in heterogeneous porous media: Spatio-temporal variation of trapping mechanisms

Oh, Junho,Kim, Kue-Young,Han, Weon Shik,Park, Eungyu Elsevier 2017 International journal of greenhouse gas control Vol.57 No.-

<P><B>Abstract</B></P> <P>We present the results of core-flooding experiments by assessing the impact of capillary heterogeneity on residual and dissolution CO<SUB>2</SUB> trapping. Two types of injection tests with different rates are conducted: single-phase (supercritical CO<SUB>2</SUB>) injection and co-injection (equilibrated CO<SUB>2</SUB> and brine) cases are considered for drainage tests. In case of the single-phase injection, CO<SUB>2</SUB> builds up at a low capillary pressure (<I>P<SUB>c</SUB> </I>) zone located upstream of a high <I>P<SUB>c</SUB> </I> zone as CO<SUB>2</SUB> was hindered to transport across the barriers. The experiments were conducted under capillary-dominated condition, and as capillary number (<I>N<SUB>c</SUB> </I>) was increased with greater injection rate, the increased viscous force led higher CO<SUB>2</SUB> saturation in fine matrix implying that high <I>P<SUB>c</SUB> </I> zone was more sensitive to the injection rate than the low <I>P<SUB>c</SUB> </I> zone. The co-injection, however, leads to greater CO<SUB>2</SUB> saturation at the high <I>P<SUB>c</SUB> </I> zone. The observed disparity of CO<SUB>2</SUB> saturation patterns in these two experiments resulted from the induced pressure gradient across the core as well as the greater capillary forces in high <I>P<SUB>c</SUB> </I> zone. The following imbibition test, which was designed to reproduce conditions for the post-injection period, characterized three regimes of spatio-temporal variation of trapping mechanisms as follows: (1) displacement of mobile CO<SUB>2</SUB> by the injected brine and concurrent CO<SUB>2</SUB> dissolution into the fresh brine; (2) preservation of immobile CO<SUB>2</SUB> as a residual trapping; and (3) gradual CO<SUB>2</SUB> dissolution into the fresh brine.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Impact of heterogeneity and injection rate on CO<SUB>2</SUB> saturation buildup was assessed. </LI> <LI> Capillary barriers in heterogeneous porous media are sensitive to injection rates. </LI> <LI> Three regimes of the spatio-temporal variation of the CO<SUB>2</SUB> trapping mechanism are characterized. </LI> <LI> Co-injection of CO<SUB>2</SUB> and water results in greater storage of CO<SUB>2</SUB> at high capillary pressure zone. </LI> </UL> </P>

Visualization of Interfacial Phenomena Enhancing Phase Change Heat Transfer

Junho Oh(오준호),A. Alperen Gunay,Soumyadip Sett 대한기계학회 2021 대한기계학회 춘추학술대회 Vol.2021 No.08

Heterogeneity effects on pressure and CO₂ saturation during core-scale multiphase flow tests

Oh, Junho,Kim, Kue-Young,Han, Weon Shik,Kim, Minji,Park, Eungyu Elsevier 2019 Journal of petroleum science & engineering Vol.172 No.-

<P><B>Abstract</B></P> <P>Carbon capture and storage (CCS) technologies can help manage current emission levels of greenhouse gases while enhancing energy security and diversifying energy economy. For a successful and effective CO<SUB>2</SUB> geological storage, a comprehensive understanding of the multiphase flow properties of the CO<SUB>2</SUB>/water system in permeable rocks is crucial because they control the engineering design and management of industrial CO<SUB>2</SUB> storage projects. In this study, we conducted multiphase flow tests at a core-scale to understand the migration behaviors of CO<SUB>2</SUB> and water in a stratified geologic media (sandstone interbedded with silt). A core-flooding apparatus combined with an X-ray scanning system provided high-resolution experimental dataset of continuous data on the differential pressure ( Δ P ) across a core plug and CO<SUB>2</SUB> saturation maps over time. During the multiphase flow tests, we captured dynamic fluctuation in Δ P as CO<SUB>2</SUB> front advanced by displacing water through different geologic media. The spatio-temporal evolution of CO<SUB>2</SUB> saturation in each geologic media revealed two increasing stages, implying that the capillary pressure of the downstream geologic media affects the upstream CO<SUB>2</SUB> saturation. In addition, multiphase transport simulations were conducted to assess the sensitivity of model parameters. Permeability and porosity were respectively sensitive to pressure and CO<SUB>2</SUB> saturation. Overall, the parameters of the silt layer were more sensitive to the pressure and CO<SUB>2</SUB> saturation build-up compared to those of the sand layer. Additionally, history matching was conducted to validate the model by sequentially matching Δ P and CO<SUB>2</SUB> saturation within the stratified system. Finally, we extended the core-scale modeling work further to field-scale and investigated the impact of boundary conditions and heterogeneity on both pressure and CO<SUB>2</SUB> saturation distribution.</P> <P><B>Highlights</B></P> <P> <UL> <LI> High-resolution dataset of pressure and CO<SUB>2</SUB> saturation from multiphase flow tests. </LI> <LI> Sensitivity analysis of petrophysical properties on pressure and CO<SUB>2</SUB> saturation build-up. </LI> <LI> History matching for pressure measurements and saturation profiles at core-scale. </LI> </UL> </P>

Behavior of sorbent particles in ceramic candle filters for multi-purpose syngas cleaning of waste gasification

( Junho Oh ),( Changkook Ryu ),( Jeongheon Kim ),( Byung Hwan Kim ) 한국폐기물자원순환학회 2023 I-CIPEC Vol.2012 No.0

Modeling and analysis of a syngas cooler with concentric evaporator channels in a coal gasification process

Junho Oh,류창국,IN-SOO YE,Sangbin Park,Sung Ku Park 한국화학공학회 2014 Korean Journal of Chemical Engineering Vol.31 No.12

Coal gasification offers a flexible and efficient conversion of the solid fuel into CO- and H2-rich syntheticgas (syngas) for production of various chemicals and energy products. Since the hot syngas leaving a gasifier containsvarious impurities such as acidic gases and particulates, it needs to be cooled down for cleaning prior to conversioninto the final product. A dedicated heat exchanger called a syngas cooler (SGC) is used to lower the gas temperaturewhile recovering the thermal energy. This study investigated the heat transfer characteristics in a commercial-scaleSGC consisting of a series of concentric helical coil channels. First, the detailed flow and heat transfer pattern in theunique heat exchanger were analyzed using computational fluid dynamics (CFD) for various operating loads and foulingconditions. The predicted heat transfer rate was used to derive correlations for Nusselt number for the channel sectionsof the SGC. Second, a one-dimensional model of the equipment was proposed for fast-response process simulations. In terms of heat transfer rate and gas temperature, the process model showed a reasonable accuracy compared to theCFD results for the tested cases.

On Whom You Spend, There Your Ethics Will Be: The Combined Effect of Spending and Construal Level on Ethical Behavior

Junho Oh(오준호),Su Sang Lee,Yunchul Shin,Jessica Seungyoon Sung,Sujin Lee 한국인사조직학회 2018 한국인사ㆍ조직학회 발표논문집 Vol.2018 No.1

Prior research has documented the strong link between money and unethicality. Our research extends previous findings by focusing on a different aspect of money: spending behavior, or on whom the money is spent. The current study integrates the spending literature and the construal level perspective to propose that individuals’ ethical behavior is determined by whom they spend their money on (the self or others) and how they think (abstractly/high-level or concretely/low-level). Experimental data show that under a high-level construal, people who spent money on others behaved more ethically than those who spent money on themselves. Under a low-level construal, however, neither prosocial nor personal spending influenced subsequent behavior related to an ethical dilemma. Thus, while people spend money on others, they should adopt an abstract, high-level construal to maintain greater integrity with regard to subsequent ethical dilemmas.

五臟辨證을 활용한 朝鮮 鍼法 硏究

오준호(Junho Oh),김남일(Namil Kim) 한국한의학연구원 2010 한국한의학연구원논문집 Vol.16 No.2

Objective : The objective of this study is to verify the characteristics of acupuncture methods of Joseon Dynasty by looking into the relationship between five viscera diagnosis and acupuncture methods. Material & Method : In the process, I've reviewed the relationship between meridian/exterior and viscera/bowels, along with a thorough comparison of the academic tendency in acupuncture of Ming-China, Qing-China and Joseon. Result & Conclusion : The two fields of meridian and exterior, and viscera and bowels had been theoretically merged, and based upon that, foundation methods applying the five viscera diagnosis were designed. Joseon acupuncture exceeded the existing concept of viscera which simply related itself to the exterior meridian and exterior by integrating the concepts from the visceral manifestation theory. With this, large proportions of medicine related to the visceral manifestation theory were invited into acupuncture, expanding therapeutic boundaries for acupuncture treatment. A historical review on medical texts starts from the Hyangyakjipseongbang(『鄕藥集成方』) which familiarized the public with mainstream acupuncture knowledge up until the Song dynasty, followed by Uibangyuchwi (『醫方類聚』), which sparked up interest on the acupuncture methods based on viscera and bowels. Donguibogam(『東醫寶鑑』) organized the medical theories up until then, building a foundation upon which viscera/bowel-based acupuncture was able to develop further. In Chimgugyeongheombang(『鍼灸經驗方』), viscera/bowel-based acupuncture methods started to blossom, integrating the meridian and exterior theory with the viscera manifestation theory, which in turn provided various methods through five viscera diagnosis. In the Saamdoin acupuncture method(舍岩道人鍼法), diagnostic criteria moved on to the five viscera diagnosis, and new methods resulting from the inter-complimentary and inter-prohibiting relationships between the five phases were introduced, opening a new world of acupuncture.

한의학 분야 번역의 현황과 과제

오준호(Oh, Junho),권오민(Kwon Ohmin) 한국고전번역원 2013 民族文化 Vol.41 No.-

본 연구는 한문으로 작성된 동아시아 전통의학 문헌들이 한국에서 어떻게 번역되어 왔는지를 거시적으로 살펴보기 위해 기획되었다. 이를 토대로 한의학 분야 번역이 지향해야할 향후 과제에 대해 고민해 보고자 한다. 한의학은 인간의 질병과 치료를 다루고 있는 실용 학문이다. 따라서 한의학 분야 번역은 특히 지식 인프라로서의 속성이 강하다. 하지만 이를 위해서는 먼저 정밀한 번역이 수행되어야 한다. 모호한 표현일수록 자세한 고증으로 독자들의 궁금증을 해소해 주어야 하며, 적절히 번역되지 않는 곳은 알 수 없다고 인정하는 용기도 필요하다. 한의학 분야에서 오역은 곧바로 잘못된 시술이나 투약으로 이어질 수 있기 때문이다. 그간 한의학 분야 번역은 한의계 내부의 역량을 주축으로 이루어져 왔다. 60년대 『동의보감』이 초역된 이래로 70년대 중요 원전 의서와 임상의서가 번역되었다. 80년대와 90년대에는 대상 서적의 범위가 확대되고 학생들까지 번역에 참여하면서 양적인 성장을 이루었다. 2000년대 이후로는 전문역자 계층이 성장하고 한의학 번역의 질적인 반성이 이루어지는 등 중요한 변화를 겪고 있다. 한의학 분야 번역은 한의학 전공자가 같은 한의학 전공자를 독자로 상정하고 이루어졌다는 특징을 가진다. 목적에 있어서도 학교 교육이나 개인의 학습을 위해 이루어지는 경우가 많았다. 이에 따라 번역 대상서 역시 인지도 높은 의서를 중심으로 편중되는 경향을 보인다. 번역에서 善本 선정과 원문 교감이 간과되거나 독자층에 대한 고려 없이 기획되는 문제들은 한의학 분야 번역이 해결해야할 문제들이다. 또 번역자원이 한 쪽으로 집중되면서 다양한 번역이 제한되는 폐단도 해소되어야 한다. 앞으로 한의학 분야 번역은 학계 내외로부터 좀 더 높은 학술적인 완성도와 체계적인 효율성을 요구받을 것이다. 정보는 책뿐만 아니라 전자매체로 공개될 것이며, 더 많은 이들이 열람하고 이용하게 될 것이다. 그간 한의학계 내부 역량만으로 많은 한의서들이 번역되어 왔지만, 번역 대상서를 다양화하고 번역의 질을 높이기 위해 한의학의 전문성은 심화시키면서도 다른 학문 분야와의 공동 번역을 지향하는 방향으로 변모해 나가야 한다. 뿐만 아니라 한의학 고유의 실용성을 살리기 위해 기획단계부터 번역 이후 활용 분야와의 연계에 대한 체계인 접근이 필요하다. This article explores the current status and future issues of the modern Korean translation of medical classics written in ancient Chinese. Korean Medicine as a scholarly endeavor is a practical science that examines the body, diseases and treatments. Thus, when it comes to the transmission of its knowledge and techniques, essential is the exact translation of ancient medical books and documents into modern vernacular language. This is because incorrect translation can lead to killing or hurting innocent people. Translators should decode, interpret and transform ambiguous, abstruse or illegible words/phrases/sentences into clear meaning as well as translate them precisely into modern language. If there is a currently unsolved issue associated with translation, translators reasonably let them clearly publicized and leave them for future research. Korean Medicine doctors and scholars have mainly engaged in translating the ancient literature of traditional Korean Medicine. Major medical canonical and clinically-oriented books were translated through to the 70s following the initiation of Donguibogam translation in the 60s. In the last two decades of the 20th century the scope of translated literature was enlarged and translating community extended to graduating classes of Korean Medicine colleges. Since the new millennium there are two game-changing shifts in relation to the translation of Korean Medicine’s literature: shaping of a professional translator group and resultant prioritizing of translational quality. Translation of Korean Medicine’s literature is characterized by the fact that inner members of Korean Medicine community straightforwardly transliterate it for peer members and is aimed at mentor-apprentice transmission or professional education of theoretical/practical medical knowledge and practices. Therefore, range of selected medical books is confined to popular and highly visible ones. Translators affiliated to the Korean Medicine professional community has yet to consider seriously issue of the authenticity of source-language texts and issue of readership. Call for translational integrity will intensify inside and outside of relevant professional groups, and scope of readership will diversify. New forms of communication channels such as web-based media have been employed beyond conventional paper and efforts will be made to discover useful knowledge for various purposes including scientific R&D and commercialization. Future issues connected to the current status of translation in Korean Medicine are as follows. Joint or team approach where heterogeneous experts participate is needed to improve translation quality. Expansion of source texts of, and thorough planning for translation are indispensable to suit changing medical, cultural and economic environments.

이색적인 문화영화: 유현목과 시네포엠(1964-66)의 실험영화 개념에 관한 제안

오준호(Junho Oh) 한국영화학회 2017 영화연구 Vol.0 No.71

시네포엠은 유현목이 1963년 제7회 샌프란시스코 국제영화제에 참석하고 돌아와서 설립했던 동인으로 전위적 단편영화의 제작을 목표로 제시했었다. 본 논문은 샌프란시스코 국제영화제가 시네포엠에 끼친 영향과 유현목과 시네포엠(1964-66)이 인식했던 실험영화가 무엇인지를 밝히는 것을 목적으로 한다. 이를 위해 우선 신문기사에 기록된 단편적 사실들을 정리한다. 그리고 유현목의 방미여정과 동시대의 미국 실험영화 지형, 샌프란시스코 국제영화제 출품작들, 시네포엠 영화감상회에서 상영되었던 작품들을 검토한다. 연구의 결과로, 1964년 당시에 유현목과 시네포엠이 인식했던 실험영화가 동시대의 북미 실험영화를 지시했을 가능성은 없다. 본 논문은 유현목과 시네포엠이 인식했던 실험영화가 ‘이색적인 문화영화’에 준하는 개념이었고, 목표로 밝혔던 전위적 단편영화의 제작은 전형적이지 않은 문화영화를 제작하겠다는 선언의 의미로 이해될 수 있다고 제안한다. Cinepoem (1964-66) was a cinema circle, which was founded by Hyun-mok Yu who had returned after attending to 1963 San Francisco International Film Festival(SFIFF). Its main objective was presented as making avant-garde short film that was an interchangeable term with experimental film. This paper aims to reveal what experimental film was meant for Yu and Cinepoem. The official records about Cinepoem have mostly been missed except few articles. For that reason, it is necessary to find out additional information useful to describe the historical background of Cinepoem. The paper will follow three traces: Yu’s itinerary in the United States and experimental film scenes in San Francisco and New York during Yu’s visit, films presented in 1963 SFIFF, and films shown in screenings held twice by Cinepoem. As a result of the review, it is unlikely that the experimental film that Yu and Cinepoem recognized was relevant to North American experimental film at the same period. The paper suggests that Yu and Cinepoem understood the experimental film as an extraordinary Culture-film. Cinepoem’s intention to make avant-garde short films can be understood as a declaration that they would create unconventional Culture-films.

모바일 디바이스와 어쿠스틱 인풋을 이용한 가상 터치 인식 기술 설계

오준호 ( Junho Oh ),최재훈 ( Jaehoon Choi ),강재우 ( Jaewoo Kang ) 한국정보처리학회 2010 한국정보처리학회 학술대회논문집 Vol.17 No.2

본 논문은 모바일 디바이스에 설치된 어쿠스틱 센서를 이용하여 가상의 터치패드를 구현하는 방법을 제시한다. 어쿠스틱 센서를 이용한 가상 터치패드 구현은 기존의 터치패드 방식에서 나타나는 대형화에 대한 한계를 극복함과 동시에 설치 및 유지비용을 낮추는데 큰 기여를 할 것으로 기대 된다. 2 대의 아이폰에 설치되어 있는 단일채널 마이크 2 개, 자이로스코프와 가속도계, 블루투스 통신을 사용하여, 정해진 경계면에서 나오는 소리의 위치를 식별하고, 이를 화면과 동기화하여 간단한 조작을 가능하게 한다.