3.0m급 저고도 장기체공 태양광 무인기 시스템 연구

정재백,김태림,김도영,문석민,배재성,박상혁 항공우주시스템공학회 2023 항공우주시스템공학회지 Vol.17 No.4

This paper describes the research and development of a 3.0 m Solar-Powered UAV system for mission flight that is based on the 4.2 m Solar-powered UAV. Both the Solar-Powered UAVs were lightened in weight by applying a composite fuselage and solar charging system. Also, a deep stall landing application and airbag module were installed for usability in mission performance. The flight performance of the Solar-Powered UAV system was verified through flight test. In particular, the 3.0 m Solar-Powered UAV performed continuous flight along the coastline of Jeju Island for 147 km in 3 hours and 50 minutes, and its performance as a mission flight was also confirmed. 본 논문은 한국항공대학교에서 연구 및 개발한 태양광 무인기에 관한 것으로, 주익 4.2 m 장기체공 태양광 무인항공기 KAU-SPUAV-2019에 대한 연구를 기반으로 하여 임무 비행을 위해 개발한 주익 3.0 m 태양광 무인항공기 KAU-SPUAV-2020의 시스템 설계에 관하여 기술하였다. 기체의 경량화를 위하여 동체에 복합재료를 적용하였고, 태양광 충전 시스템을 적용하였다. 임무 수행 활용성을 위하여 비상시 긴급하게 착륙하기 유리하도록 Deep Stall Landing이 가능하도록 제작하였으며, 강제 실속 착륙 시 항공기에 가해지는 충격을 흡수하기 위한 에어백 모듈을 장착하였다. 개발된 3.0 m 태양광 무인항공기의 비행 성능 및 임무 수행 능력은 비행 실험을 통해 그 수행 능력을 검증하였으며, 147 km에 달하는 제주도 해안선을 3 시간 50 분 만에 비행하는 것에 성공함으로 태양광 무인항공기가 다양한 분야에서 촬영, 모니터링 임무에 활용 가능함을 확인하였다.

Targeted cellular delivery of robust enzyme nanoparticles for treating drug-induced hepatotoxicity

정재백,정지훈,이민상,김다훤 한국공업화학회 2019 한국공업화학회 연구논문 초록집 Vol.2019 No.0

We synthesized hydrophilic natural polymer with inorganic calcium phosphate for the facile preparation of a SOD-containing bio-hybrid nanoparticle system. The polymer has multiple functions such as liver-targeting property, endosomal escape function, and desirable stability in the blood stream. d-HA/SOD was synthesized by reacting catechol moieties of d-HA with surface amines of SOD. CaP/d-HA/SOD was successfully prepared and stabilized by preventing excessive growth of CaP and inter-particular aggregation. Cellular uptake of CaP/d-HA/SOD was significantly increased by CD44-mediated endocytosis and dissociation of calcium and phosphate ions. The targeted nanoparticles not only improved radical scavenging activity but also reduced oxidative stress-mediated apoptosis. Systemically injected CaP/d-HA/SOD showed therapeutic effects in preventing APAP-induced hepatic toxicity and injury in animals.

Targeted cellular delivery of injectable enzyme nanoparticles for treating drug-induced hepatotoxicity and liver injury

정재백,이민상,김다훤,정지훈 한국공업화학회 2019 한국공업화학회 연구논문 초록집 Vol.2019 No.1

Direct delivery of proteins into cells has been considered an effective approach for treating the protein-related diseases. To achieve an efficient cellular delivery of the protein, a multifunctional carrier system having desirable stability, cell-targeting property and endosomal escape functions may be required. d-HA/SOD was synthesized by reacting catechol moieties of d-HA with surface amines of SOD. CaP/d-HA/SOD was successfully prepared and stabilized by preventing excessive growth of CaP and inter-particular aggregation. Cellular uptake of CaP/d-HA/SOD was significantly increased by CD44-mediated endocytosis and dissociation of calcium and phosphate ions. The nanoparticle achieved the efficient hepatic cellular delivery of SOD via a systemic administration and resulted in efficient removal of reactive oxygen species (ROS) in the liver and remarkable improvement of APAP-induced hepatotoxicity and liver injury.

한국항공대학교 저고도 장기체공 태양광 무인기 개발에 관한 연구 (1) - 주익 4.2m 태양광 무인기 시스템 설계 -

정재백,김도영,김태림,문석민,배재성,박상혁 한국항공우주학회 2022 韓國航空宇宙學會誌 Vol.50 No.7

본 논문은 한국항공대학교에서 연구 및 개발한 태양광 무인기 KAU-SPUAV에 관한 내용으로, 2020년 6월 32시간 19분 장기체공 비행에 성공한 주익 4.2m 태양광 무인기의 설계 과정에 관하여 기술하였다. 태양광 무인기의 장기체공 능력을 향상시키기 위해 항력을 줄이기 위한 원형 단면의 동체를 설계하였고, 유리섬유 복합재를 사용한 모노코크 구조를 적용하여 가볍고 튼튼한 동체를 제작하였다. 또한 4.2m 태양광 무인기의 날개 형상에 최적화된 태양광 모듈을 구성하여 배열하였고, 23[in] x 23[in] 프로펠러를 적용한 추진시스템을 구성하여 충전 및 비행 효율을 향상시켰다. 개발된 태양광 무인기는 순항할 때 평균 55W를 소비하고, 주간에 최대 165W 에너지를 공급받을 수 있으며 비행실험을 통해 장기체공 성능을 검증하였다.

초음파와 전기분해를 이용한 수중의 난분해성 유기물질의 분해 특성

정재백,이성호,배준웅,Jeong, Jae-Baek,Lee, Seong-Ho,Bae, Jun-Ung 대한화학회 2006 대한화학회지 Vol.50 No.6

refractory organic compounds in aqueous solution are not readily removed by the existing conventional wastewater treatment process. In recent years, the sonolysis and electrochemical oxidation process had been shown to be promising for wastewater treatment due to the effectiveness and easiness in operation. This study was performed to investigate the characteristics of sonolytic and electrolytic decomposition as the basic data for development of the wastewater treatment process. Trichloroethylene(TCE) and 2,4- dichlorophenol(2,4-DCP) were used as the samples, and their destruction efficiency were measured with various operating parameters, such as initial solution concentration, initial solution pH, reaction temperature, sonic power and current density. Also, the decomposition mechanism conformed indirectly with the effect of NaHCO3 as a radical scavenger on the decomposition reaction. Thermal decompositon reaction is predominant for TCE but thermal and radical decompositon reactions were dominant for 2,4-DCP. Results showed that the destruction efficiencies of all samples were above 65% within 120 minutes by sonolysis and electrolysis at the same time, and were increased with increasing initial concentration, sonic power and current density. Destruction efficiency of TCE was high in the acidic solution, but 2,4-DCP showed high destruction efficiency in basic solution. 폐수처리방법으로는 분해가 어려운 유해화합물을 효과적으로 정화처리 할 수 있는 방법 개발을 위해, 최근 주목받고 있는 새로운 AOP(advanced oxidation process, 고급산화법) 공정인 초음파분해와 전기분해를 함께 이용하여 연구하였다. 대상 물질은 TCE(trichloroethylene)와 2,4-DCP(2,4-dichlorophenol)이며, 각 공정의 분해효율과 특성을 구하기 위해 각 시료물질들에 대해 초기농도, 초기 pH, 초음파 power 그리고 전류밀도 등을 변화시키며 최적 분해 조건을 조사하였다. 또한 시료물질에 대한 라디칼 포착제로 알려진 NaHCO3의 영향을 조사하여 각 시료물질의 분해반응 경로를 간접적으로 확인한 결과는 다음과 같다. TCE는 열분해반응이 지배적이며, 2,4-DCP 경우는 열분해반응 못지않게 라디칼 분해반응도 경쟁적으로 일어난다는 것을 알 수 있었다. 초음파와 전기분해를 동시에 적용시켰을 때, 두 시료 모두에서 120분 이내, 65% 이상 제거율을 보였으며, 제거율은 초기농도가 높을 때 그리고 초음파 power와 전류밀도가 증가할수록 향상되었다. 그리고 초기수용액의 pH 영향 실험에서는 TCE는 산성수용액에서 제거율이 높지만 2,4-DCP의 경우에는 알칼리성 수용액에서 제거율이 높은 것으로 나타났다.

Enhanced cancer chemo-immunotherapy using nanomicelle generating microneedles containing paclitaxel and TLR7/8 agonist

정재백,정지훈,김다훤,임수연,조희주,김동민 한국공업화학회 2020 한국공업화학회 연구논문 초록집 Vol.2020 No.-

A dissolving microneedle(MN) for transdermal drug delivery is an attractive method to improve therapeutic efficacy. Efficient delivery of low dose chemotherapeutic agent-paclitaxel and immunostimulatory adjuvants-resiquimod was synergized to demonstrate tumor killing effect and activation of antigen presenting cells. In this research, both therapeutic agents being water insoluble were dispersed with the help of amphiphilic triblock copolymer: Pluronic F127 based dissolving MNs in situ that generate nanomicells (NMCs) upon their dissolution after cutaneous application. Various Cancer cells were significantly killed via paclitaxel and combination of paclitaxel and resiquimod in vitro, while antigen presenting cells (dendritic cells) treated with same concentration of resiquimod along with the combination led to enhanced proliferation. In DCs, as to extraordinarily enhanced secretion of pro-inflammatory, the combination resulted in a considerable synergy effect for the immune responses.

모핑 조종면을 갖는 무인항공기 체계 및 비행시험

정재백(Jaebaek Jeong),배재성(Jae-Sung Bae) 한국항공우주학회 2023 한국항공우주학회 학술발표회 논문집 Vol.2023 No.4

Vascular endothelial growth factor-induced angiogenesis and experimental corneal neovascularization are successfully suppressed by using apatinib-loaded nanoparticles

조희주,정재백,임수연,김다훤,김동민,정지훈 한국공업화학회 2020 한국공업화학회 연구논문 초록집 Vol.2020 No.-

Pathological angiogenesis is one of the major symptoms of severe ocular diseases, including corneal neovascularization. treating corneal neovascularization. In this study, we aimed to investigate whether nanoparticle-based delivery of apatinib, a selective inhibitor of vascular endothelial growth factor(VEGF) receptor 2, inhibits VEGF-mediated angiogenesis. In a rat model of alkali burn injury-induced corneal neovascularization, a subconjunctival injection of apatinib-loaded HSA-PEG (Apa-HSA-PEG) nanoparticles decreases in neovascularization compared to free apatinib solution. These in vitro and in vivo results demonstrate that apatinib-loaded nanoparticles may be promising for the prevention and treatment of corneal neovascularization-related ocular disorders.

Hyaluronic Acid/Calcium Phosphate Hybrid Gene Delivery System facilitates osteogenic differentiation of Human Mesenchymal Stem Cells

조희주,정재백,임수연,김다훤,김동민,정지훈 한국공업화학회 2020 한국공업화학회 연구논문 초록집 Vol.2020 No.-

Human mesenchymal stem cells (hMSC) are one of the stem cells that have multipotent properties. Despite their boundless possibility, current use of hMSCs in clinics is still limited because differentiation of hMSCs to desired cells is often difficult to control especially in vivo situation. Herein, biologically acceptable calcium phosphate (CaP)-based nanoparticles stabilized with a catechol-derivatized hyaluronic acid (dopa-HA) conjugate were used as a carrier for gene transfection to hMSCs for improved differentiation. Owing to the specific binding between HA and CD44 of bone marrow-derived hMSCs, dopa-HA/CaP showed significantly higher transfection in hMSCs than branched polyethylenimine (bPEI, MW 25 kDa) with high biocompatibility. The co-delivery of a plasmid DNA encoding bone morphogenetic protein 2 (BMP-2 pDNA) and micro RNA 148b (miRNA-148b) by dopa-HA/CaP successfully achieve improved osteogenic differentiation of hMSCs.

PEGylated human serum albumin nanocarrier for chemotherapy

김동민,정재백,임수연,김다훤,조희주,정지훈 한국공업화학회 2020 한국공업화학회 연구논문 초록집 Vol.2020 No.-

Paclitaxel(PTX) is representative chemo-drug which has high effect and low solubility. PTX needs oil/detergent-based solvent to be dissolved due to its poor solubility in an aqueous environment. However, those formulations often cause undesirable complications including hypersensitivity reactions and limited tumor distribution, resulting in a lower dose than recommended dose. Now, we introduce a facile and oil free method to prepare albumin-based PTX nanoparticles for efficient systemic cancer therapy using a conjugate of human serum albumin (HSA) and poly(ethylene glycol) (PEG). PTX were efficiently incorporated in the self-assembled PEGyl-HSA nanoparticles (PEGyl-HSA/PTX) using a simple film casting and re-hydration procedure without additional processes such as application of high pressure/shear or chemical crosslinking. The spherical PEGyl-HSA nanoparticle mediates efficient cellular delivery, leading to high cytotoxicity in various breast cancer cells.