http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Reliability-guaranteed multipath allocation algorithm in mobile network
Jaewook Lee(Jaewook Lee),Haneul Ko(Haneul Ko) 한국전자통신연구원 2022 ETRI Journal Vol.44 No.6
The mobile network allows redundant transmission via disjoint paths to support high-reliability communication (e.g., ultrareliable and low-latency communications [URLLC]). Although redundant transmission can improve communication reliability, it also increases network costs (e.g., traffic and control overhead). In this study, we propose a reliability-guaranteed multipath allocation algorithm (RG-MAA) that allocates appropriate paths by considering the path setup time and dynamicity of the reliability paths. We develop an optimization problem using a constrained Markov decision process (CMDP) to minimize network costs while ensuring the required communication reliability. The evaluation results show that RG-MAA can reduce network costs by up to 30% compared with the scheme that uses all possible paths while ensuring the required communication reliability.
Jaewook Lee,Jaeman Jang,Hyeongjung Kim,Jiyoul Lee,Bang-Lin Lee,Sung-Jin Choi,Dong Myong Kim,Dae Hwan Kim,Kyung Rok Kim IEEE 2014 IEEE electron device letters Vol.35 No.3
<P>The physical origins of the negative-bias stress (NBS) instability in polymer-based thin-film transistors have been characterized. Through the quantitative analysis by TCAD simulation for the NBS time-dependent experimental results, the threshold voltage (V<SUB>T</SUB>)-shift by sub-bandgap density-of-states redistribution forms 70% and 78% for the measured total V<SUB>T</SUB>-shift while V<SUB>T</SUB>-shift by gate oxide charge trapping only takes 30% and 22% at NBS time of 3000 and 7000 s, respectively. In addition, the increase of source/drain Schottky contact resistance (R<SUB>SD</SUB>) is the main reason for NBS-induced on -current (I<SUB>ON</SUB>) degradation.</P>
Lee, Jaewook,Kim, JiEun,Go, Jun,Lee, Jong Ho,Han, Dong-Wook,Hwang, DaeYoun,Lee, Jaebeom Elsevier 2015 Colloids and surfaces Biointerfaces Vol.135 No.-
<P><B>Abstract</B></P> <P>The biological activities and therapeutic potential of phytochemical-decorated Au nanoparticles (Phyto-AuNPs) were investigated through the treatment of Phyto-AuNPs on the dorsal skin of rats via transdermal drug delivery process in order to regenerate surgical wounded and burned skin. Two different Phyto-AuNPs were applied to the dorsal skin: gallic acid–isoflavone – covered AuNPs (GI-AuNPs) and protocatechuic acid–isoflavone – covered AuNPs (PI-AuNPs). From the biological activity monitoring, it has been resulted that 5-fold thicker epidermis (ER), 50% reduction of metalloproteinase-1 (MMP-1) level, 3-fold higher superoxide dismutase (SOD) activity were obtained in the Phyto-AuNP-treated group, compared with a vehicle group (deionized water (DI-water) treatment). Moreover, the Phyto-AuNPs treatment on the surgical and burn damaged Sprague-Dawley (SD) rats induced higher expression of vascular endothelial growth factor (VEGF) and angiopoietin-2 (Ang-2). It would be plausible that antioxidant property of Phyto-AuNPs assist the acceleration and activation of biomolecules in the healing mechanism, where Phyto-AuNPs can be potential candidates for skin regeneration and wound healing.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Phytochemical decorated Au nanoparticles (Phyto-AuNPs) have been eco-friendly synthesized using gallic acid, protocatechuic acid and isoflavone without thermal and pressure assistance. </LI> <LI> According to hairless mouse dorsal skin test, it was proved that Phyto-AuNPs exhibited anti-oxidant effect and skin regeneration property. </LI> <LI> Phyto-AuNPs also showed wound healing properties for surgically damaged and burned dorsal skins of SD rats via transdermal treatment. </LI> <LI> These bioactive nanomaterials can be used for the excellent skin therapy agents. </LI> </UL> </P>
Investigation of carbon nanomaterials via metal-oxide catalytic pyrolysis of waste mask
Do Hyun Lee(Do Hyun Lee),Jaewook Myung(Jaewook Myung) 유기성자원학회 2022 유기성자원학회 학술발표대회논문집 Vol.2022 No.추계
Owing to the continuous demand for masks caused by the continued COVID-19, several waste masks made of recalcitrant plastics have accumulated in nature, causing environmental and societal problem in the waste management process for smart cities. To deal with this present issue, metal-oxide catalytic pyrolysis process was conducted. The catalyst was prepared using nickel and iron through the impregnation method in which metal oxide (alumina (Al2O3) and zeolite (ZSM-5)) were selected as a support. Carbon nanomaterials were observed on the nickel-doped metal oxide catalyst surface, and a growth mechanism of carbon nanomaterial on the surface of iron-nickel doped zeolite was identified by Transmission Electron Microscope (TEM). These findings are expected to contribute to the development of sustainable plastic recycling technology aimed at creating value-added products in connection with the government's waste upcycling project.
Adhesion of Kraft Lignin-Based Polyurethane Adhesives for Wood Bonding
( Jaewook Lee ),( Byung-dae Park ) 한국목재공학회 2022 한국목재공학회 학술발표논문집 Vol.2022 No.2
The abundance of natural polymers such as lignin has been attracting much attention as a raw material for polyurethane (PU) resin adhesives. PU resins have excellent adhesion performance due to strong urethane bonds, and also do not release any toxic substance after curing. The objective of this study is to characterize non-isocyanate-based PU (NIPU) resins synthesized with softwood kraft lignin (KL), and to optimize the adhesion of NIPU resins for plywood. Acetone fractionation of crude KL (CKL) was done to produce acetone soluble KL (ASKL). NIPU resins were synthesized with CKL or ASKL for NIPU resin adhesives. CKL- and ASKL-NIPU resins show a similar FTIR spectra. Tensile shear strength showed that CKL-NIPU met the standard requirement of plywood. This result suggests that CKL-NIPU resins are suitable adhesive with favorable tensile shear strength (TSS) of and formaldehyde emission from plywood. Subsequently, a silane coupling agent was added to speed up the curing of KL-NIPU adhesives.
Lee, Jaewook,Kim, Dongjin,Nomura, Tsuyoshi,Dede, Ercan M.,Yoo, Jeonghoon Elsevier 2018 COMPOSITE STRUCTURES -BARKING THEN OXFORD- Vol.201 No.-
<P><B>Abstract</B></P> <P>This paper presents a topology optimization method for the sequential design of material layout and fiber orientation in functionally graded fiber-reinforced composite structures. Specifically, the proposed method can find the optimal structural layout of matrix and fiber materials together with optimal discrete fiber orientations. In this method, an orientation design variable in the Cartesian coordinate system is employed with a conventional density design variable. The orientation design variable controls not only the fiber orientation, but also fiber volume fraction. The fiber volume fraction control can be used to relax the orientation design problem and simultaneously design a functionally graded structural layout of fiber material. To avoid intermediate fiber orientations and achieve discrete fiber orientation design, a penalization scheme is applied to the orientation design variable. For solving the optimization problem which involves multiple design variables such as the density variable, fiber orientation variable, and target discrete orientation set, a three-step sequential optimization procedure is proposed. In this procedure, the result for each step provides the isotropic design, continuous fiber orientation design, and functionally graded discrete orientation design, respectively. To validate the effectiveness of the proposed approach, numerical examples for structural compliance minimization and compliant mechanism design are provided.</P>
Lee Jaewook,Ahn Jin Hwan,Lee Ingyu,Cho Yongun 대한정형외과 스포츠의학회 2020 Arthroscopy and Orthopedic Sports Medicine Vol.7 No.1
We report a case of pathologic bilateral impingement of the posterior cruciate ligament (PCL) synovial folds referred to PCL plicae. A 40-year-old female was admitted to the hospital with vague bilateral knee pain along the medial side of both knees just below each patella. She reported that standing for long periods of time increased the pain and that it has been more than 10 years since the vague pain occurred. On magnetic resonance imaging, medial synovial folds of the PCL were identified and therefore knee arthroscopy was performed under general anesthesia. The arthroscopic findings revelated entrapped folds within the medial tibiofemoral joints when the knees were in passive extension. The entrapped tissue of the synovial folds was resected by punch forceps and debrided by a shaver. After eight months of surgery, the patient’s symptoms completely resolved, and she regained full range of motion. The long medial synovial folds around the PCL can be a cause of knee pain due to entrapment between the femoral and tibial condyles. Plicae pathologies can therefore be considered one of the differential diagnosis of vague knee pain.
Lee, Minsup,Yun, Seohyeon,Lee, Hyesook,Yang, Jaewook MDPI 2017 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol.18 No.12
<P>Retinal vascular endothelial growth factor (VEGF) increased by neovascularization is well known as a pathogenic factor in ocular neovascular diseases. However, it is still unclear how retinal neurons are damaged by VEGF. The aims of this study are to demonstrate the inflammatory protein expression regulated by VEGF using mouse photoreceptor-derived cells and the protective effect of quercetin against VEGF-induced inflammatory response. Expression and phosphorylation of protein and expression of mRNA were detected by immunoblot and reverse transcriptase polymerase chain reaction. VEGF-induced degradation of limiting membrane and translocation of nuclear factor kappa B (NF-κB) were analyzed by immunocytochemistry. VEGF treatment activated angiogenic signaling pathway in photoreceptor cells. In addition, adhesion molecules and matrix metalloproteinases were increased in VEGF-treated photoreceptor cells. All these events were reversed by quercetin. Zona occludins-1 and β-catenin decreased by VEGF were recovered by quercetin. NF-κB signaling pathway regulated by VEGF through phosphorylations of mitogen-activated protein kinases (MAPK) and protein kinase B (Akt) was suppressed by quercetin. These results suggest that quercetin suppressed VEGF-induced excessive inflammatory response in retinal photoreceptor cells by inactivation of NF-κB signals through inhibition of MAPKs and Akt. These data may provide a basic information for development of pharmaceuticals or nutraceuticals for treatment of retinal diseases caused by excessive VEGF.</P>