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Microstructure and Optical Properties of Yttrium-doped Zinc Oxide(YZO) Nanobolts Synthesized by Hydrothermal Method

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Journal of Materials Science & Technology 2016年第1期32卷 12-16页

作者： Sanjeev K.Sharma deuk Young kim Semiconductor Materials and Device Laboratory Department of Semiconductor ScienceDongguk University-Seoul

In this work, yttrium-doped zinc oxide （YZO） nanopowder was synthesized via hydrothermal precipitation- method. The microstructure and optical properties of yttrium-doped zinc oxide nanopowder were characterized, which confirmed the well-crystalline wurtzite hexagonal phase of ZnO. The yttrium- doped zinc oxide nanopowder grains formed the nanobolts of -400 nm in length and -900 nm in width. High resolution-transmission electron microscopy （HR-TEM） of the nanobolts revealed uniform lattice fringes and no visible faults and/or distortions. X-ray photoelectron spectroscopy （XPS） analysis con- firmed the presence of yttrium in the zinc oxide lattice, proving the contribution of yttrium on the microstructural and optical properties of the material. A strong ultra violet （UV） emission peak of the YZO exhibited a red shift compared to pure zinc oxide, which was ascribed to the defects and the for- mation of a shallow energy level caused bv the incorporation of yttrium.

关键词： YZO nanobolts Hydrothermal synthesis Microstructural Optical properties

Effect of nanoclay on properties of porous PVdF membranes

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 141-147页

作者： Hae-Young HWANG deuk-Ju kim Hyung-Jun kim Young-Taik HONG Sang-Yong NAM School of Materials Science and Engineering Engineering Research Institute i-Cube Center Gyeongsang National University Fuel Cell Research Center Korea Institute of Science and Technology Seoul 136-791 Korea Energy Material Research Center Korea Research Institute of Chemical Technology Daejeon 305-600 Korea

The main requirements for battery separators are high porosity which can serve pathways of lithium ion and space for gel electrolytes to impregnate in a membrane and mechanical strength to allow easy handling for battery assembly. Generally, it appears the trade-off relationship between the porosity and mechanical strength of the membrane. PVdF composite membranes containing nano-size clays were used to improve the mechanical strength of the membrane without affecting the membrane porosity. The composite membranes were prepared by phase inversion method controlling the membrane preparation conditions such as retention time. The resultant membranes show increased mechanical properties with similar membrane porosity around 80 % compared to the pristine PVdF membrane. Incorporation of nonoclay can be considered as an effective method to improve the mechanica! strength in porous membrane supports, especially in a separator.

关键词： Li-ion battery separator poly(vinylidene fluoride) nanocomposite

Preparation and Characterization of Porous PVdF-HFP/clay Nanocomposite Membranes

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Journal of Materials Science & Technology 2010年第7期26卷 633-638页

作者： Mi Jin Koh Hae Young Hwang deuk Ju kim Hyeng Jun kim Young Taik Hong Sang Yong Nam School of Materials Science and Engineering Engineering Research Institutei-Cube CenterGyeongsang National UniversityJinjuKorea Fuel Cell Research Center Korea Institute of Science and TechnologySeoul 136-791Korea Energy Material Research Center Korea Research Institute of Chemical TechnologyDaejeon 305-600Korea

Polyvinylidene fluoride-hexafluoropropylene （PVdF-HFP） / clay nanocomposite membranes were prepared by phase inversion method through controlling retention time to apply for a lithium ion secondary batteries. Increased membrane porosity with macrovoids was observed at increasing retention time. Partially intercalated structures of PVdF-HFP/clay nanocomposite membranes were confirmed by X-ray diffraction （XRD） analysis. PVdF-HFP membranes containing various kind of clay showed the increase of membrane modulus compared to the pristine PVdF-HFP membrane.

关键词： PVdF-HFP Porosity Mechanical properties Clay Separator

Network Intrusion Detection in Internet of Blended Environment Using Ensemble of Heterogeneous Autoencoders(E-HAE)

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Computer Systems Science & Engineering 2023年第9期46卷 3261-3284页

作者： Lelisa Adeba Jilcha deuk-Hun kim Julian Jang-Jaccard Jin Kwak ISAA Lab. Department of AI Convergence NetworkAjou UniversitySuwon16499Korea ISAA Lab. Institute for Information and CommunicationAjou UniversitySuwon16499Korea Department of Computer Science and Information Technology Massey UniversityAuckland0745New Zealand Department of Cyber Security Ajou UniversitySuwon16499Korea

Contemporary attackers,mainly motivated by financial gain,consistently devise sophisticated penetration techniques to access important information or *** growing use of Internet of Things(IoT)technology in the contemporary convergence environment to connect to corporate networks and cloud-based applications only worsens this situation,as it facilitates multiple new attack vectors to emerge *** such,existing intrusion detection systems suffer from performance degradation mainly because of insufficient considerations and poorly modeled detection *** address this problem,we designed a blended threat detection approach,considering the possible impact and dimensionality of new attack surfaces due to the aforementioned *** collectively refer to the convergence of different technology sectors as the internet of blended *** proposed approach encompasses an ensemble of heterogeneous probabilistic autoencoders that leverage the corresponding advantages of a convolutional variational autoencoder and long short-term memory variational *** extensive experimental analysis conducted on the TON_IoT dataset demonstrated 96.02%detection ***,performance of the proposed approach was compared with various single model(autoencoder)-based network intrusion detection approaches:autoencoder,variational autoencoder,convolutional variational autoencoder,and long short-term memory variational *** proposed model outperformed all compared models,demonstrating F1-score improvements of 4.99%,2.25%,1.92%,and 3.69%,respectively.

关键词： Network intrusion detection anomaly detection TON_IoT dataset smart grid smart city smart factory digital healthcare autoencoder variational autoencoder LSTM convolutional variational autoencoder ensemble learning

Biliary phytobezoar resulting in intestinal obstruction

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World Journal of Gastroenterology 2013年第1期19卷 133-136页

作者： Yura kim Beom Jin Park Min Ju kim deuk Jae Sung Dong-Sik kim Young-Dong Yu Jeong Hyeon Lee Department of Radiology College of MedicineKorea UniversityAnam HospitalSeoul 136-705South Korea Division of HBP Surgery and Liver Transplantation Department of SurgeryCollege of MedicineKorea UniversityAnam HospitalSeoul 136-705South Korea Department of Pathology College of MedicineKorea UniversityAnam HospitalSeoul 136-705South Korea

Phytobezoar is the most common type of *** is composed of indigestible vegetable matter and is usually found in the *** phytobezoar is extremely rare and difficult to diagnose *** pathogenesis is not clear,and there have been only a few reports of biliary bezoars associated with sphincteric impairmentat the ampulla of ***,we present a report of biliary bezoar that resulted in jejunal *** were unable to identifythe bezoar in the extrahepatic bile duct until it obstructed the small bowel *** our knowledge,this is the first report of small bowel obstruction resulting frommigration of a biliary bezoar.

关键词： Phytobezoar Biliary Intestinal obstruction Choledochoduodenal Fistula Multidetector-row computed tomography

Cystic Brunner's gland hamartoma in the duodenum:A case report

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World Journal of Gastroenterology 2009年第39期15卷 4980-4983页

作者： Beom Jin Park Min Ju kim Jeong Hyeon Lee Sung-Soo Park deuk Jae Sung Sung Bum Cho Department of Radiology Korea UniversityCollege of MedicineAnam Hospital Department of Pathology Korea UniversityCollege of MedicineAnam Hospital Department of Surgery Korea UniversityCollege of MedicineAnam Hospital

Cystic Brunner's gland hamartoma in the duodenum is exceedingly rare,although microscopic examination may sometimes reveal a Brunner's gland hamartoma containing dilated ducts in the *** present a case of large cystic Brunner's gland hamartoma in the duodenum with a long stalk,which is described in light of multidetector-row computed tomography,magnetic resonance imaging,and a modified small bowel series,together with pathologic correlation and differential diagnosis.

关键词： Brunner's gland Hamartoma Duodenum Multidetector-row computed tomography Magnetic resonance imaging

The predictability of T3 disease in staging MRI following prostate biopsy decreases in patients with high initial PSA and Gleason score

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Asian Journal of Andrology 2011年第3期13卷 487-493,515页

作者： Young Hwii Ko deuk Jae Sung Sung Gu Kang Seok Ho Kang Jeong Gu Lee Je Jong kim Jun Cheon Department of Urology Korea University School of Medicine Seoul Korea Department of Radiology Korea University School of Medicine Seoul Korea

To obtain improved accuracy in predicting extracapsular extension （ECE） and seminal vesicle invasion （SVI）, we evaluated the variables affecting the predictability of staging magnetic resonance imaging （MRI, phased-array coil） and estimated their impact on accuracy between preoperative MRI staging and histological outcome. A total of 121 patients with localized or locally advanced prostate cancer who underwent robotic radical prostatectomy （RALP） were included. Following transrectal biopsy, all enrolled patients had undergone MRI for staging work-up. After RALP, only 43.8% （53/121） of the patients were matched with the MRI predicted stage. Compared to the matched group in the prediction of ECE, the unmatched group had significantly higher initial prostate-specific antigen （PSA, 12.8 ng m1-1 versus 8.1 ng m1-1, P=0.048）. In the prediction of SVI, initial PSA （8.1 ng ml- 1 versus 17.3 ng ml- 1, P=0.009） and biopsy Gleason score （6.5 versus 7.6, P=0.035） were significantly higher in the unmatched group. When applying clinical cutoffs of initial PSA of 10 and 20 ng ml-1, the accuracy of MRI in the prediction of ECE was decreased in the group with PSA over 20 ng ml- 1 （75.6, 64.5 and 37.5%, P=0.01）, and this group had significantly decreased accuracy of MRI in the prediction of SVI （91.5, 77.4 and 37.5%, P〈0.01）. Applying the clinical cutoff of a Gleason score of 7, the accuracy of MRI in the prediction of SVI was decreased in the higher G leason score group （93.9, 82.1 and 62.9%, P= 0.01）. Thus, for these patient groups, to obtain margin negativity during radical prostatectomy, operative findings, rather than post-biopsy MRI images, may provide substantial information, implying a clinical advantage in conducting MRI before prostate biopsy.

关键词： magnetic resonance imaging neoplasm staging prostatic neoplasms

Perfluorooctanoic acid(PFOA) and perfluorooctanesulfonic acid(PFOS) concentrations in the South Korean agricultural environment: A national survey

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Journal of Integrative Agriculture 2017年第8期16卷 1841-1851页

作者： Geun-Hyoung Choi deuk-Young Lee Dong-Kyu Jeong Saranya Kuppusamy Yong Bok Lee Byung-Jun Park Jin-Hyo kim Chemical Safety Division National Institute of Agricultural ScienceRural Development Administration Division of Applied Life Science(BK21 Plus) Institute of Agriculture and Life Science(IALS)Gyeongsang National University

Research on the occurrence of perfluorochemicals （PFCs） such as perfluorooctanesulfonic acid （PFOS） and perfluorooctanoic acid （PFOA） in the agricultural environment is lacking, in spite of their potential risk via food chain transfer from aquatic and soil-plant systems to animals and/or humans. In the present study, for the first time, soil and water samples collected from 243 different agricultural sites adjacent to waste water treatment plants （WWTPs） belonging to 81 cities and 5 provinces with different levels of industrialization in South Korea were monitored for concentrations of PFOS and PFOA by use of solid phase extraction and liquid chromatography-tandem mass spectroscopy （LC-MS/MS）. Significant mean concentrations of PFOA （0.001-0.007 tJg L-1 water and 〈0.05-1.573 tJg kg-1 soil） and PFOS （0.001-0.22 tJg L-1 water and 〈0.05-0.741 pg kg-1 soil） were found in all samples. Concentrations of PFCs in soils were high, highlighting that soil is an important sink for PFCs in the agricultural environment. Samples from near WWTPs in Gyeongsang Province contained the highest concentrations of PFOS and PFOA, reflecting the concentration of heavy industry in the province. The concentrations of PFCs in agricultural water （most samples 〈0.05 pg L-~） and soils （most samples 〈1 IJg kg-~） from South Korea were less than acceptable guideline values, indicating that South Korea is not a hotspot of PFOS and PFOA contamination and that there is negligible risk to human and ecological health from these chemicals. However, further studies investigating the seasonal variation in PFOA, PFOS and other perfluorochemical concentrations in the agricultural environment are needed.

关键词： PFOS PFOA agricultural environment residual concentration South Korea

Effects of Korean ginseng berry extract （GB0710） on penile erection： evidence from in vitro and in vivo studies

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Asian Journal of Andrology 2013年第4期15卷 503-507,I0008页

作者： Kang Su Cho Chan Woong Park Chun-Ki kimt Hee Young Jeon Wan Gi kim Sang Jun Lee Young-Myeong kim Joo Yong Lee Young deuk Choi Department of Urology Severance Hospital Urological Science Institute Yonsei University College of Medicine Seou1120-752 Korea R&D Center Amorepacific Corporation Yongin Gyeonggi-do 446-729 Korea Vascular System Research Center and Department of Molecular and Cellular Biochemistry School of Medicine Kangwon National University Chunchon 200-701 Korea and Clinical Trial Center for Medical Devices Yonsei University College of Medicine Seoul 120-752 Korea

Several reports have promoted the root-derived Korean red ginseng （KRG; Panax ginseng） as alternative treatment for erectile dysfunction （ED）, and ginsenosides are known to be the principal active ingredients of ginseng. Recent studies showed that ginseng berries produce more ginsenosides than KRG; thus, we investigated the ability of the Korean ginseng berry extract GB0710 to relax the penile corpus cavernosum smooth muscle （CCSM） in this study. As a comparative control, the results were compared to those obtained using KRG. In addition, possible mechanisms of action for GB0710 were investigated. While KRG and GB0710 both displayed dose-dependent relaxation effects on precontracted rabbit CCSM in vitro, GB0710 was shown to be more potent than KRG. The GBO710-induced relaxation could be partially reduced by removing the endothelium. In addition, pre-treatment with several nitric oxide （NO） inhibitors significantly inhibited the relaxation of muscle strips. Furthermore, administration of GB0710 increased intracavernosal pressure （ICP） in a rat in vivo model in both a dose- and duration-dependent manner. Intracellular NO production in human microvascular endothelial cells could be induced by GB0710 and inhibited by NG-monomethyI-L-arginine. In conclusion, GB0710 had a greater relaxation effect on rabbit CCSM than did KRG extract, and increased ICP in a rat model in both a dose- and a duration-dependent manner. This relaxine effect might be mediated bv NO production.

关键词： corpus cavernosum erectile dysfunction (ED) ginseng berry nitric oxide (NO) smooth muscle