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The 3-Hour-interval Prediction of Ground-Level Temperature in South Korea Using Dynamic Linear Models

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Advances in Atmospheric Sciences 2003年第4期20卷 575-582页

作者： Keon-Tae SOHN deuk-KyunRHA young-KyungSEO Dept.of Statistics Pusan National University30 Jangjeon-dongGeumjung-guPusan609-735KoreaKorea Meteorological Administration460-18 Shindaebang-dongTongjak-guSeoul156-720KoreaKorea Meteorological Administration460-18 Shindaebang-dongTongjak-guSeoul156-720Korea

The 3-hour-interval prediction of ground-level temperature from +00 h out to +45 h in South Korea (38 stations) is performed using the DLM (dynamic linear model) in order to eliminate the systematic error of numerical model forecasts. Numerical model forecasts and observations are used as input values of the DLM. According to the comparison of the DLM forecasts to the KFM (Kalman filter model) forecasts with RMSE and bias, the DLM is useful to improve the accuracy of prediction.

关键词： temperature forecasting systematic error dynamic linear model

Effect of nanoclay on properties of porous PVdF membranes

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Transactions of Nonferrous Metals Society of china 2011年第A01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

Observational Study of Surface Wind along a Sloping Surface over Mountainous Terrain during Winter

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Advances in Atmospheric Sciences 2018年第3期35卷 276-284页

作者： young-Hee LEE Gyuwon LEE Sangwon JOO Kwang-deuk AHN Department of Astronomy and Atmospheric Sciences Kyungpook National University Numerical Data Application Division Numerical Modeling Center

The 2018 Winter Olympic and Paralympic Games will be held in Pyeongchang, Korea, during February and March. We examined the near surface winds and wind gusts along the sloping surface at two outdoor venues in Pyeongchang during February and March using surface wind data. The outdoor venues are located in a complex, mountainous terrain, and hence the near-surface winds form intricate patterns due to the interplay between large-scale and locally forced winds. During February and March, the dominant wind at the ridge level is westerly; however, a significant wind direction change is ob- served along the sloping surface at the venues. The winds on the sloping surface are also influenced by thermal forcing, showing increased upslope flow during daytime. When neutral air flows over the hill, the windward and leeward flows show a significantly different behavior. A higher correlation of the wind speed between upper- and lower-level stations is shown in the windward region compared with the leeward region. The strong synoptic wind, small width of the ridge, and steep leeward ridge slope angle provide favorable conditions for flow separation at the leeward toot of the ridge. The gust factor increases with decreasing surface elevation and is larger during daytime than nighttime. A significantly large gust factor is also observed in the leeward region.

关键词： flow separation gust factor leeward region sloping surface

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

The optimal timing of post-prostate biopsy magnetic resonance imaging to guide nerve-sparing surgery

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Asian Journal of Andrology 2014年第2期16卷 280-284,I0010页

作者： young Hwii Ko Phil Hyun Song Ki Hak Moon Hee chang Jung Jun cheon deuk Jae Sung Department of Urology Yeuflgnam University School of Medicine Daegu Korea Department of Urology Korea University School of Medicine Seoul Korea Department of Radiology Korea University School of Medicine Seoul Korea

The goal of our study was to evaluate the impact of the interval between prostate biopsy and magnetic resonance imaging （MRi） on the accuracy of simple tumor localization, which.is essential information that enables nerve-sparing surgery. We also sought to determine the optimal timing of a post-biopsy MRi, A total of 184 patients who had undergone MRi before radical prostatectomy at an institution without a predetermined schedule for MRi after a prostate biopsy were enrolled. The mean interval from the biopsy to the MRi was 30.8 ± 18.6days. The accuracy of the MRi for simplified tumor location （right, left, bilateral and none） was 44.6%. in the group with discordant pathologic and MRi findings, the most common reason recorded was ＇MRi predicted a unilateral lesion, but pathology revealed bilateral lesions＇（58.3%）, followed by ＇MRi predicted no lesion, but pathology revealed the presence of a lesion＇（32.0%）. Multivariable analysis showed that the discordant group had a shorter interval （25.0 ± 14.3 vs 38.1 ± 20.6days, P 〈 0.01） preceding the MRi and a higher rate of hemorrhage as observed by MRi （80.4% vs 54.8%, P 〈 0.01） in comparison with the accordant group. in receiver operating characteristics analysis, the area under the curve of the MRi interval in accurate prediction of the tumor location was 0.707 （P 〈 0.001）. At the MRi interval＇s cutoff of 28.5days, the sensitivity was 73.2% and the specificity was 63.7%. When the MRi was performed within 28days, the accumulated accuracy was only 26.1% （23/88）; however, when it was performed after 28days, the reversely accumulated accuracy was 61.5% （59/96）. These data support a waiting period of at least 4weeks after a biopsy before performing an MRi for the purposes of surgical refinement.

关键词： magnetic resonance imaging nerve preservation prostate biopsy radical prostatectomy

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 ch.i 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

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

Upgrading and upstaging of low-risk prostate cancer among Korean patients： a multicenter study

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Asian Journal of Andrology 2015年第5期17卷 811-814,I0009页

作者： insang Hwang Donghoon Lim young Beom Jeong Seung chol Park Jun Hwa Noh Dong deuk Kwon Taek Won Kang Department of Urology Chonnam National University Medical School Gwangju Korea Department of Urology Chosun University Medical School Gwangju Korea Department of Urology Chonbuk National University Medical School Jeonju Korea Department of Urology Wonkwang University School of Medicine Iksan Korea Department of Urology Kwangju Christian Hospital Gwangju Korea

Only 54% of prostate cancer cases in Korea are localized compared with 82% of cases in the US. Furthermore, half of Korean patients are upgraded after radical prostatectomy （41.6%-50.6%）. We investigated the risk factors for upgrading and/or upstaging of low-risk prostate cancer after radical prostatectomy. We retrospectively reviewed the medical records of 1159 patients who underwent radical prostatectomy at five hospitals in Honam Province. Preoperative data on standard clinicopathological parameters were collected. The radical prostatectomy specimens were graded and staged and we defined a ＂worsening prognosis＂ as a Gleason score ≥ 7 or upstaging to ≥ pT3. Multivariate logistic regression models were used to assess factors associated with postoperative pathological upstaging. Among the 1159 patients, 324 were classified into the clinically low-risk group, and 154 （47.5%） patients were either upgraded or upstaged. The multivariable analysis revealed that the preoperative serum prostate-specific antigen level （odds ratio [OR], 1.131; 95% confidence interval [Ci], 1.007-1.271; P = 0.037）, percent positive biopsy core （OR： 1.018; 95% Ci： 1.002-1.035; P = 0.032）, and small prostate volume （≤30 ml）（OR： 2.280; 95% Ci： 1.351-3.848; P = 0.002） were predictive of a worsening prognosis. Overall, 47.5% of patients with low-risk disease were upstaged postoperatively. The current risk stratification criteria may be too relaxed for our study cohort.

关键词： prostate cancer prostatectomy risk factors

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 ch.i 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 ch.in 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