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Velocity Profiles between Two Baffles in a Shell and Tube Heat Exch.nger

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Journal of Thermal Science 2015年第4期24卷 356-363页

作者： Tae-Hyun ch.ng ch.ng-Hoan lee Hae-soo lee Kwon-soo lee Senior Research Fellow of RESEAT Korea Institute of Science and Technology Information Korea Institute of Science and Technology Information Postdoctoral Research Fellow School of Mechanical Engineering of Kyungnam University International University of Korea

Heat exch.ngers are extensively utilized for waste heat recovery,oil refining,chemical processing,and steam *** this study,velocity profiles are measured using a 3D particle image velocimetry(PIV)system between two baffles in a shell and tube heat exch.nger for parallel and counter *** PIV and computational fluid dynamics results show the occurrence of some strong vectors near the *** vectors are assumed due to the clearance between the inner tubes and the front ***,the major parts of the vectors are moved out through the bottom opening of the rear baffle,and other vectors produce a large circle between the two *** simulations are conducted to investigate the effects of the baffle on the heat exch.nger using the Fluent *** k-εturbulence model is employed to calculate the flows along the heat exch.nger.

关键词： Baffle P1V Shell and tube heat exch.nger Cut off ratio CFD

Luminescence properties of Eu^(2+),Gd^(3+) and Pr^(3+) doped translucent Sialon phosphors

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Journal of Rare Earths 2015年第11期33卷 1142-1147页

作者： Bhupendra Joshi soo Wohn lee Research Center for Eco Multi-Functional Nano Materials Sun Moon University

Optical properties of hot pressed Sialon ceramics doped with different rare earth oxides（REOs） i.e. Eu2O3, Gd2O3, and Pr2O3 were investigated. The α-Sialon phase was the main phase obtained after sintering as observed by X-ray diffraction（XRD）. The transparency of different samples of varying thickness measured from UV to IR region revealed that the samples were translucent in the visible region while transparent in IR region. The thin samples of 150 μm thickness had transmittance as high as 30% in the visible region. The luminescence was observed in transmittance mode to investigate the effect of sample thickness on luminescence intensity. We observed blue, yellow and red emissions in Sialon doped with Gd2O3, Eu2O3, and Pr2O3, respectively. The excitation wavelength for Gd2O3 and Pr2O3 doped samples were in UV region i.e. 280 and 270 nm, respectively, whereas, for Eu2O3 doped samples was in the blue region（460 nm）. The Eu2O3 doped Sialon having 300 μm thickness showed better white light extraction as coupled with blue LED. Moreover, the fabricated phosphor samples exhibited high hardness around 20 GPa and fracture toughness above 5 MPa·m1/2.

关键词： Sialon phosphors luminescence rare earth oxides hot pressing

A New FIR Filter for State Estimation and Its Application

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Journal of Computer Science & Technology 2007年第5期22卷 779-784页

作者： Pyung-soo Kim Myung-Eui lee Department of Electronics Engineering Korea Polytechnic University Shiheung CityKgunggi-DoKorea School of Information Technology Korea University of Technology and Education cheonan City Chungnam-DoKorea

This paper proposes a new FIR （finite impulse response） filter under a least squares criterion using a forgetting factor. The proposed FIR filter does not require information of the noise covariances as well as the initial state, and has some inherent properties such as time-invariance, unbiasedness and deadbeat. The proposed FIR filter is represented in a batch form and then a recursive form as an alternative form. Prom discussions about the choice of a forgetting factor and a window length, it is shown that they can be considered as useful parameters to make the estimation performance of the proposed FIR filter as good as possible. It is shown that the proposed FIR filter can outperform the existing FIR filter with incorrect noise covariances via computer simulations. Finally, as a useful application, an image sequence stabilization problem is considered. Through this application, the FIR filtering based approach is shown to be superior to the Kalman filtering based approach.

关键词： state estimation FIR (finite impulse response) filter Kalman filter least squares forgetting factor

Factors associated with strabismus after cataract extraction and primary intraocular lens implantation in congenital cataracts

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International Journal of Ophthalmology(English edition) 2014年第3期7卷 522-527页

作者： soo Jung lee Wan-soo Kim Department of Ophthalmology Haeundae Paik Hospital

AIM:To evaluate factors associated with the development of strabismus after cataract extraction and primary intraocular lens ***:The medical records of 122 patients,aged1.5mo to 9y,who had undergone cataract extraction with primary intraocular lens implantation between January1993 and August 2011 were *** patients(17 eyes)with strabismus before cataract surgery were *** were divided into those with congenital bilateral cataracts(64 patients,128 eyes)and those with unilateral cataracts(44 patients,44 eyes).The associations between the development of strabismus and age at cataract surgery,pre-and post-cataract extraction corrected distance visual acuity(CDVA),interocular CDVA difference,nystagmus,surgical method,and secondary cataract were ***:Factors significantly associated with the development of strabismus included age at cataract surgery(≤1y),preoperative mean CDVA≤20/100,presence of nystagmus in the bilateral cataract group and postoperative interocular CDVA difference>20/70 in the unilateral *** CDVA≤20/100 and preservation of posterior capsule,and presence of secondary cataract were significant factors in both ***:children with congenital cataracts should be monitored carefully after cataract surgery for the development of strabismus,especially when they underwent surgery at age≤1y,and they have nystagmus,large postoperative interocular CDVA difference,poor preoperative and postoperative CDVA,preservation of the posterior capsule,or secondary cataract.

关键词： strabismus congenital cataract nystagmus

Factors influencing stereoacuity levels after surgery to correct unilateral developmental cataracts in children

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International Journal of Ophthalmology(English edition) 2013年第3期6卷 331-336页

作者： soo Jung lee Wan-soo Kim Department of Ophthalmology Haeundae Paik Hospital

·AIM: To evaluate factors influencing stereoacuity after surgery to correct unilateral developmental pediatric cataracts. ·METHODS: We retrospectively surveyed 110 patients who had undergone removal of unilateral acquired developmental cataracts and primary posterior chamber intraocular lens implantation between February 1992 and December 2009. In all patients, stereoacuity was assessed using the Titmus test at the last follow -up period of minimum 2 years after surgery. Patients were divided into two groups according to the extent of stereoacuity : group 1 ( = 42 ) had stereoacuity values ≤ 100sec/arc and group 2 ( =68) values >100sec/arc. The values of ten parameters associated with stereoacuity were measured in each group: Cataract types, preoperative best corrected visual acuity (BCVA) of the affected eyes, preoperative inter -ocular difference of BCVA, age at cataract surgery, operative method, secondary cataract, postoperative strabismus, postoperative BCVA of the affected eyes, postoperative inter-ocular difference of BCVA, and anisometropia. ·RESULTS: The extent of stereoacuity was significantly associated with both operative method and secondary cataract ( =0.000 and =0.016, respectively). All patients in whom the posterior capsule was preserved, had poor stereoacuity >100sec/arc. Significant correlations with the extent of stereoacuity were found with postoperative strabismus ( =0.048),postoperative BCVA of the affected eyes ( =0.002), anisometropia ( =0.034). ·CONCLUSION: Postoperative stereoacuity was better in patients who underwent either optic capture or anterior vitrectomy after posterior continuous curvilinear capsulorhexis, and who didn’t develop secondary cataracts or strabismus postoperatively. Furthermore, postoperative BCVA of the affected eyes, and anisometropia influenced the stereoacuity of the patients surgically treated for unilateral developmental pediatric cataracts. ·

关键词： anisometropia developmental cataract secondary cataract stereoacuity stereopsis strabismus unilateral pediatric cataract visual acuity

Synthesis of tin nanoparticles through modified polyol process and effects of centrifuging and drying on nanoparticles

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中国有色金属学会会刊：英文版 2012年第S3期22卷 707-711页

作者： Sang-soo chEE Jong-Hyun lee Department of Materials Science and Engineering Seoul National University of Science and Technology

Sn nanoparticles with average diameter of 13.1 nm were synthesized by modified polyol process,and their melting point was observed to be about 40 °C less than that of bulk *** though Sn nanoparticles are solid and covered with thin PVP capping and oxide layer,Sn nanoparticles in solution agglomerate upon centrifugation,resulting in a melting point *** to stickiness of the PVP capping layer,extensive aggregation between Sn nanoparticles was observed after ***,the aggregation behavior did not further influence the melting point,because actual agglomeration did not occur in the aggregates.

关键词： tin nanoparticle melting point centrifugation agglomeration aggregation

Comparison of soil bacterial diversity and community composition between clear-cut logging and control sites in a temperate deciduous broad-leaved forest in Mt. Sambong, South Korea

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Journal of Forestry Research 2020年第6期31卷 2367-2375页

作者： Byeong-Ju lee soo Hyung Eo Department of Forest Resources Kongju National UniversityYesanChungnam 32439Republic of Korea

Deforestation or clear-cut logging affects forest ecosystems,including soil microbial *** purpose of this study was to investigate the effects of clearcut logging on the soil bacterial community in a temperate deciduous broad-leaved forest on ***,South *** investigated the physicochemical characteristics and bacterial diversity of the soil in clear-cut logging and control *** available phosphorus(AP)level in soil was significantly lower in the clear-cut sites than in the control;however,the other physicochemical properties of soil were similar at the two *** examining the bacterial 16S rRNA gene using next-generation sequencing,we found that the number of bacterial taxa at the species and phylum level were similar at the control and clear-cut *** with the high resilience of bacterial communities and absence of ch.nge in the soil physicochemical properties—with the exception of AP—we found similar levels of bacterial diversity at the two *** most taxa showed similar composition ratios at the control and the clear-cut sites,some taxa such as Deltaproteobacteria,Ktedonobacteriales,Myxocccales,Polyangiaceae,Pedosphaera_f,and Solibacter showed differences after clear-cut *** conclude that AP was significantly associated with those bacterial taxa that showed differences in their composition ratios following clear-cut logging.

关键词： Forest soil Metagenomics Pyrosequencing Soil physicochemical characteristics

Macrophage activation syndrome in children with Kawasaki disease: diagnostic and therapeutic approaches

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World Journal of Pediatrics 2020年第6期16卷 566-574页

作者： Seung Beom Han soo-Young lee Department of Pediatrics Daejeon St.Mary's Hospital.College of MedicineThe Catholic University of Korea64 Daeheung-ro.Jung-guDaejeon 34943Republic of Korea Department of Pediatrics.Bucheon St.Mary's Hospital College of MedicineThe Catholic University of Korea327 Sosa-roWonmi-gu.Bucheon 14647Republic of Korea

Background Macrophage activation syndrome(MAS)is a rare,life-threatening complication of Kawasaki disease(KD).Early recognition and treatment of MAS are very important,but sometimes it is difficult to distinguish MAS from a severe form of *** sources A PubMed search was performed in Clinical Queries using the key terms“macrophage activation syndrome or secondary hemophagocytic lymphohistiocytosis(HLH)”and“Kawasaki disease”.Results KD patients with MAS show high intravenous immunoglobulin(IVIG)resistance and coronary *** is also as high as MAS in other *** fever greater than 10 days is highly associated with development of MAS in *** is observed in more than two-thirds of KD patients with *** is often the earliest laboratory finding of *** is highly specific and sensitive for detecting MAS in KD;so,ferritin levels should be checked if there are unexplained clinical exacerbations in KD *** the under-recognition of MAS in KD,it is prudent to consider resistant KD as occult/subclinical *** KD patients with MAS have good outcomes on immune ***,if KD patients fulfill the HLH-2004 diagnostic criteria,they may undergo longer and more intensive treatment than *** The possible existence of MAS should be taken into account when a KD patient shows persistent fever,splenomegaly,thrombocytopenia,hyperferritinemia,or IVIG *** under-diagnosis of MAS in patients with KD is an important issue to be ***,however,there is a possibility of over-treatment of MAS in patients with KD.

关键词： Macrophage activation syndrome Kawasaki disease children

Recoverable SnO_2-Based Sensors Promoted with MoO_3 and Sb_2O_3 for the Detection of DMMP

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稀有金属材料与工程 2006年第A03期35卷 155-156页

作者： Woo Suk lee Ho Yun choi soo chool lee soo Jae lee Duk Dong lee Jeung soo Huh Jae ch.ng Kim Department of chemical Engineering Kyungpook National UniversityDaegu 702-701Korea School of Electrical Engineering and Computer Science Kyungpook National UniversityDaegu 702-701Korea Department of Materials Science and Metallurgy Kyungpook National UniversityDaegu 702-701Korea

The sensitivity and the recovery behavior of SnO_2-based gas sensor prepared from a commercial SnO_2 powder were tested under the low concentration of DMMP(0.5μg/g) in the flow system at 350℃.In order to improve the sensitivity of the sensor,promoters such as NiO,Nb_2O_5,MoO_3,and Sb_2O_3 were added into SnO_2 *** sensitivities were increased up to 80% from 50% but they were not *** the SnO2-based gas sensor promoted with MoO_3 and Sb_2O_3 was recovered after detection of DMMP,although the recovery rate was *** particular,the SnO_2-based sensor promoted with 5wt% of MoO_3 and 1wt% of Sb_2O_3 simultaneously showed an complete recovery ability,though its sensitivity was 40% which was lower than that of SnO_2 gas sensor without *** ability was discussed in terms of catalytic roles of promoters.

关键词： SnO2 MoO3 Sb2O3 sensor,recovery DMMP