혼합미생물배양체를 이용한 폐활성슬러지 가용화 산물로부터 polyhydroxyalkanoate 생합성

박태준,유영재,정동훈,이선희,이영하,Park, Taejun,Yoo, Young Jae,Jung, Dong Hoon,Lee, Sun Hee,Rhee, Young Ha 한국미생물학회 2017 미생물학회지 Vol.53 No.3

SA-TSA 복합구를 이용해 폐활성슬러지로부터 VFAs를 생산하고, 이를 발효 기질로 이용해 PHA를 생산하기 위한 실험을 수행하였다. 30%의 SA-TSA 복합구를 처리하였을 때 폐활성슬러지의 가용화 효율이 가장 효과적으로 일어나서 약 3,900 mg/L의 SCOD값을 얻었으며, acetic acid, propionic acid, iso-butyric acid 및 butyric acid를 주성분으로 하는 2,961 mg/L 농도의 VFAs를 얻었다. VFAs를 외부탄소원으로 이용하는 SBR 공정을 통해 PHA를 생합성하는 미생물을 농화배양하는 실험을 수행하고 PCR-DGGE로 분석한 결과, 우점 미생물로 Vibrio spp.와 Corynebacterium glutamicum이 확인되었다. 폐활성슬러지로부터 얻은 VFAs를 탄소원으로 사용하여 농화된 혼합미생물배양체를 회분배양한 결과, 건체량의 25.9%에 달하는 PHB를 얻었다. 본 연구결과는 SA-TSA 복합구를 이용하여 폐활성슬러지로부터 VFAs를 얻음으로써 폐슬러지 감량화 효과를 얻고, 또 혼합미생물배양체를 이용하여 VFAs를 바이오폴리머로 전환함으로써 경제성을 확보할 수 있는 새로운 생물공정의 가능성을 보여준다. A new approach to the solubilization of waste activated sludge (WAS) using alginate-quaternary ammonium complex beads was investigated under controlled mild alkaline conditions. The complex beads were prepared by the reaction of sodium alginate (SA) with 3-(trimethoxysilyl)propyl-octadecyldimethylammonium chloride (TSA) in acid solution, followed by crosslinking with $CaCl_2$. Treatment of WAS with SA-TSA complex beads was effective for enhancing the efficacy of WAS solubilization. The highest value of soluble chemical oxygen demand (SCOD) concentration (3,900 mg/L) was achieved after 10 days of treatment with 30% (v/v) SA-TSA complex beads. The WAS solubilization efficacy of the complex beads was also evaluated by estimating the concentrations of volatile fatty acids (VFAs). The maximum value of VFAs was 2,961 mg/L, and the overall proportions of VFAs were more than 75% of SCOD. The main components of VFAs were acetic, propionic, iso-butyric, and butyric acids. These results suggest that SA-TSA complex beads might be useful for enhancing the solubilization of WAS. The potential use of VFAs as the external carbon substrate for the production of polyhydroxyalkanoate (PHA) by a mixed microbial culture (MMC) was also examined. The enrichment of PHA-accumulating MMC could be achieved by periodic feeding of VFAs generated from WAS in a sequencing batch reactor. The composition of PHA synthesized from VFAs mainly consisted of 3-hydroxybutyrate. The maximum PHA content accounted for 25.9% of dry cell weight. PHA production by this process is considered to be promising since it has a doubly beneficial effect on the environment by reducing the amount of WAS and concomitantly producing an eco-friendly biopolymer.

자동차용 토크컨버터 부품 최적화

박태준(Taejun Park),문성영(Sungyoung Moon),김영일(Youngil Kim),장재덕(Jaeduk Jang) 한국자동차공학회 2007 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

New competitive products must meet the growing demands of the market. They must be light-weighted, resource-efficient, durable, stable, and have a low noise emission. At the same time, the product must be introduced quickly into the market. These demands can only be met if structural optimization tools are used in addition to established CAE, CAD, DMU, and PDM systems. Variation calculations and improvements can be carried out on the digital prototype at a very early project stage. Accordingly, the number of required prototypes can be reduced which results in possible time and cost savings. The paper shows a torque converter optimization for proof the value of optimization.

소아에서 발생하는 이시성 서혜부 탈장에 대한 임상적 고찰

박태준(Taejun Park),정은영(Eunyoung Jung),박우현(Woo-Hyun Park),최순옥(Soon-Ok Choi) 대한외과학회 2011 Annals of Surgical Treatment and Research(ASRT) Vol.80 No.2

Purpose: The purpose of this study is to identify the incidence of metachronous contralateral inguinal hernia (MCH) and how early patients visit hospital upon discovering the presence of a lump on the contralateral side after initial hernia repair. Methods: This is a retrospective study of 2,169 patients with inguinal hernia between January 2001 and January 2010 at a single institution. We evaluated the occurrence of MCH among 1,689 consecutive unilateral inguinal hernia (UIH) patients who were treated in our department. We also analyzed and compared the time lag (number of days) between noticing the presence of hernia and hospital visit between UIH and MCH. Results: A total of 102 patients with MCH underwent initial UIH repair during the study period. The incidence of MCH was 6.0% and was slightly higher in males (6.7%) than in females (3.5%). The patients with left inguinal hernia (7.3%) had higher incidence of developing MCH than those with right (5.2%). When we analyzed the patients with MCH, 69.6% of them were under age 5 and 74.6% of MCH occurred within 2 years after initial UIH repair. Seventy-three percent of the patients with MCH, whose time lag was over one month when the first episode of UIH occurred, visited hospital later as MCH occurred. Conclusion: The incidence of MCH within the study period is 6.0%. It is slightly higher in males and in patients with left inguinal hernia. Most MCH occurred under age 5 and within 2 years after initial UIH repair.

토크 컨버터 록업클러치의 용량설계에 관한 연구

박태준(Taejun Park),홍순석(Soonseok Hong),장재덕(Jaeduk Jang),주인식(Insik Joo) 한국자동차공학회 2007 한국자동차공학회 Symposium Vol.- No.-

New torque converter clutch works at low speed area for high fuel efficiency. This trend caused heat problem of friction material in lock-up clutch. Heat may cause the damage of friction material. Friction material require cooling flow rate for guarantee of material life. In order to improve cooling, Torque converter adapted the system by introducing the cooling hole in lock-up piston. However cooling hole causes torque drop because the oil flow for cooling lowers the pressure in the clutch piston. Torque converter designers should consider proper flow rate and torque for engine. Therefore the torque and hole size estimation is required for the early stage of torque converter design. Estimation equation was derived based on the physical background such as the centrifugal force, sudden expansion, sudden contraction and Bernoulli’s equation.

소프트웨어 정의 네트워크 기반 리플렉터넷

박태준(Taejune Park),이승수(Seungsoo Lee),신승원(Seoungwon Shin) 한국통신학회 2014 韓國通信學會論文誌 Vol.39 No.6(네트워크)

소프트웨어 정의 네트워킹(SDN)은 기존의 네트워킹 구조와는 상이하게 제어 계층과 데이터 계층이 분리되어 있어 데이터 계층을 중앙 집중 형태로 제어할 수 있는 네트워킹 구조로서 차세대 네트워킹 기술로 강력히 거론되고 있다. 이러한 기술을 잘 활용하면, 새롭고 다양한 네트워크 기능을 어플리케이션의 형태로 개발이 가능하여, 현재 해당 분야에 대한 연구가 활발히 이루어지고 있다. 뿐만 아니라, 새로운 라우팅 기능 등과 같은 기본적인 네트워크 기능 외에도 네트워크 보안 기능 또한 SDN 기술을 활용하면 재설계가 가능하여 흥미로운 네트워크 보안 애플리케이션들이 다수 제안되었다. 그러나 현재까지 제안된 네트워크 보안 애플리케이션들은 대부분 기존의 네트워크 기능을 SDN기술을 활용하여 재구현하였기 때문에, SDN이 제공하는 많은 기능들을 효과적으로 사용하지는 못하였다. 따라서 본 논문에서는 SDN기술을 사용하여 악성 및 의심스러운 네트워크 공격 시도를 허니팟과 같은 감시/분석 시스템으로 재전송(redirect)해주는 기능인 리플렉터넷(Reflectornet)애플리케이션을 설계하고 구현하였다. 또한, 해당 애플리케이션의 성능과 실용성을 실험을 통해 검증한다. 본 논문의 결과는 SDN 기술을 사용하여 더 지능적이고 진보된 네트워크 보안 애플리케이션을 설계하는 방법에 대한 연구를 촉진하는데 큰 기여를 할 수 있을 것이다. Software-Defined Networking (SDN), which separates the control plane from the data plane and manages data planes in a centralized way, is now considered as a future networking technology, and many researchers and practitioners have dived into this area to devise new network applications, such new routing methods. Likewise, network security applications could be redesigned with SDN, and some pioneers have proposed several interesting network security applications with SDN. However, most approaches have just reimplemented some well-known network security applications, although SDN provides many interesting features, They didn’t effectively use them. To investigate if we can use SDN in realizing sophisticated network security applications, we have designed and implemented an advanced network security application, Reflectornet, which redirects malicious or suspicious network trials to other security monitoring points (e.g., honeypot). In addition, we have tested its performance and practicability in diverse angles. Our findings and some insights will encourage other researchers to design better or intelligent network security applications with SDN.

구조용 헬기 시뮬레이터 개발을 위한 영상 S/W 기본설계

박태준(Taejun Park),김동현(Donghyun Kim),성은혜(Eunhye Sung),윤석준(Sugjoon Yoon),신현욱(Hyunwook Shin) 한국항공우주학회 2016 한국항공우주학회 학술발표회 논문집 Vol.2016 No.11

토크 컨버터의 가압 스핀 해석

박태준(Taejun Park),장재덕(Jaeduk Jang),주인식(Insik Joo) 한국자동차공학회 2008 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

This paper discussed deformation of torque converter at lock-up mode. It was mainly verified by high spin experiment, so this paper made an attempt to analyze high spin experiment by structural analysis. To analyze high spin experiment, 1/4 FEM model was made. And, cyclic symmetry condition and pressure included the centrifugal force were used. By analysis results. it showed that analysis results agree with experiment results at less than 3000rpm. And, because of plastic deformation at more than 3000rpm, analysis results make a difference with experiment results.

블루투스를 이용한 DirectShow기반의 H.264 동영상 플레이어의 설계 및 구현

박태준(Taejun Park),조태훈(Tai-Hoon Cho) 한국지능시스템학회 2009 한국지능시스템학회 학술발표 논문집 Vol.19 No.1

본 논문에서는 블루투스를 이용한 DirectShow기반의 H.264 동영상 플레이어의 구현에 대해 기술한다. 블루투스는 근거리상의 디바이스들을 무선으로 연결하여 통신하는 기술이고 DirectShow는 Microsoft사가 개발한 멀티미디어 프레임워크이자 API로 소스필터 기반이다. 동영상 스트리밍 데이터를 블루투스를 이용하여 전송을 하고 DirectShow기반의 필터가 데이터를 받아 해당 데이터를 필요로 하는 필터에게 보내게 된다. 이 때 블루투스로부터 데이터를 받게 되는 부분은 쓰레드를 생성하여 데이터를 받도록 구현하였다.

가상 네트워크 인터페이스 카드와 소프트웨어 스위치를 활용한 이기종간 통신

박태준(Taejune Park),우승원(Seungwon Woo),신승원(Seungwon Shin) 한국통신학회 2017 한국통신학회 학술대회논문집 Vol.2017 No.11

오픈플로우 흐름표 (Flow Table) 분석을 통한 이상행위 탐지 시스템

박태준(Taejune Park),신승원(Seungwon Shin) 한국통신학회 2018 한국통신학회 학술대회논문집 Vol.2018 No.6