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Snowstorm over the Southwestern Coast of the Korean Peninsula Associated with the Development of Mesocyclone over the Yellow Sea

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Advances in Atmospheric Sciences 2008年第5期25卷 765-777页

作者： Ki-Young HEO kyung-Ja ha Division of Earth Environmental System College of Natural Sciences Pusan National University Korea

This study investigates the characteristics of a heavy snowfall event over the southwestern part of the Korean Peninsula on 4 December 2005. The snowstorm was a type of mesoscale maritime cyclone which resulted from barotropic instability, and diabatic heating from the warm ocean in continental polar air masses. Based on surface observations, radiosonde soundings, MTSAT-1R satellite data and the 10-km grid RDAPS （Regional Assimilation and Prediction System based on the PSU/NCAR MM5） data, the evolution of the mesocyclone is explained by the following dynamics; （1） In the initial stage, the primary role in the cyclogenesis process of the mesocyclone is a barotropic instability in the horizontal shear zone. （2） In the developing stage, the mesocyclone moves and deepens into a baroclinic zone corresponding to the surface heating and moistening. （3） In the mature stage, it is found that the mesocyclone is intensified by the destabilization caused by enhanced low-level heating and condensation, the moisture flux convergence, and the interaction between upper and lower-level potential vorticity anomalies. We suggest that a checklist with stepwise indicators responsible for development be prepared for the forecasting of heavy snowfall over the southwestern part of the Korean Peninsula.

关键词： heavy snowfall mesocyclone baroclinic instability barotropic instability stepwise roles potential vorticity anomalies

Implementation of Turbulent Mixing over a Stratocumulus-Topped Boundary Layer and Its Impact in a GCM

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Advances in Atmospheric Sciences 2009年第5期26卷 995-1004页

作者： Sun-Hee SHIN kyung-Ja ha Division of Earth Environmental System Pusan National University

The effect of a vertical diffusion scheme over a stratocumulus topped boundary layer （STBL） was investigated using the YONU AGCM （Yonsei University Atmospheric General Circulation Model）. To consider the impact of clouds on the turbulence production, the turbulence mixing term, driven by radiative cooling at the cloud top, is implemented as an extended non-local diffusion scheme. In the model with this new scheme, the STBL parameterization significantly influences the lower atmosphere over the tropical and subtropical regions. Consideration of the turbulent mixing within the cloud layer leads to continuous stratocumulus formation. The cloud-top radiative cooling tends to favor more rapid entrainment and produces top-down turbulent mixing. This cooling develops a mixed layer without initiation of deep convection by surface fluxes. Variations in thermodynamical and dynamical features are produced by planetary boundary layer （PBL） cloud development. The simulated stratocumulus induces more mixing of heat and moisture due to the cloud forcing. Over STBL regions, the lower boundary layer becomes warmer and drier. It also weakens vertical motion and zonal trade winds in the eastern Pacific, which indicates that stratocumulus cloud cover plays a role in weakening the Walker circulation; that is, cloud cover damps the tropical circulation.

关键词： stratocumulus topped boundary layer non-local diffusion scheme tropical circulation general circulation model

Association between Tropical Convection and Boreal Wintertime Extratropical Circulation in 1982/83 and 1988/89

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Advances in Atmospheric Sciences 2003年第4期20卷 593-603页

作者： Ja-Yeon MOON kyung-Ja ha Climate Research Laboratory Meteorological Research InstituteSeoul156-720KoreaDepartment of Atmospheric SciencesPusan National UniversityPusan609-735Korea

Boreal wintertime extratropical circulation is studied in relation to the tropical convection during the 1982/83 El Niño and 1988/89 La Niña. The anomaly structure of 1982/83 and 1988/89 over the extratropics reveals remarkably different features as the longitudinal tropical forcing region changes. The Rossby wave source (Positive) shows the largest maximum over East Asia in both years due to the persistent heating from the western Pacific warm pool area. However, the sink term shows contrasting features over the subtropics and extratropics between the two years. In the El Niño year, enhanced tropical convection over the eastern Pacific produces the Rossby wave sink at 10°N and shifted eastward over the North Pacific, while in the La Niña year, the sink area is shifted westward over the North Pacific. The contrasting features between the two events in mean-eddy interaction appears especially over the downstream area of the East Asian Jet. The extension (retraction) of the meanflow eastward (westward) to the east (west) of the dateline is related with the effect of the westward (eastward) E-vector and the strengthening (weakening) of the negative anomalies of the barotropic growth of kinetic energy. Hence, almost opposite characteristics between the two events can explain the close relationship of tropical convection and the extratropical internal variability.

关键词： tropical convection extratropical circulation rossby wave source mean-eddy interaction

Optimal Spatial Allocation of Initial Attack Resources for Firefighting in the Republic of Korea Using a Scenario Optimization Model

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Journal of Mountain Science 2014年第2期11卷 323-335页

作者： Yohan LEE Byungdoo LEE kyung ha KIM Korea Rural Economic Institute 117-3 Hoegi-ro Dongdeamun-guSeoul 130-710 South Korea Korea Forest Research Institute Hoegiro 57 Dongdaemun-guSeoul 130-712 South Korea

【Title】 This study explores the optimal spatial allocation of initial attack resources for firefighting in the Republic of Korea. To improve the effectiveness of Korean initial attack resources with a range of policy goals, we create a scenario optimization model that minimizes the expected number of fires not receiving a predefined response. In this study, the predefined response indicates the number of firefighting resources that must arrive at a fire before the fire escapes and becomes a large fire. We use spatially explicit GIS-based information on the ecology, fire behavior, and economic characterizations important in Korea. The data include historical fire events in the Republic of Korea from 1991 to 2007, suppression costs, and spatial information on forest fire extent. Interviews with forest managers inform the range of we address in the decision model. Based on the geographic data, we conduct a sensitivity analysis by varying the parameters systematically. Information on the relative importance of the components of the settings helps us to identify “rules of thumb” for initial attack resource allocations in particular ecological and policy settings.

关键词： Spatial allocation Initial attack Firefighting The Republic of Korea Senario optimization

Comparison of the clinical efficacy of medical treatment of symptomatic benign prostatic hyperplasia between normal and obese patients

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Asian Journal of Andrology 2011年第5期13卷 728-731页

作者： Seung Hwan Lee Cheol Young oh kyung Kgi Park Mutt Su Chung Se Jeong Yoo Byung ha Chung Department of Urology Yonsei University Health System Seoul Korea Department of Urology Hallym University Anyang 431-070 Chuncheon

We aimed to investigate the difference in efficacy of medical treatment of symptomatic benign prostatic hyperplasia （BPH） between normal and obese patients with BPH; obesity was determined by either body mass index （BMI） or waist circumference （WC）. In this 12-week prospective observational study, a total of 175 patients aged ≥40 years with International Prostate Symptom Scores （IPSS） ≥12 points and prostate volume≥20 ml were prospectively enrolled. The patients were divided into two groups according to BMI or WC. Patients received the doxazosin gastrointestinal therapeutic system （GITS） at a dose of 4 mg once per day for 12 weeks. The changes from baseline in the IPSS, maximal urinary flow rate （Qmax）, post-void residual volume, quality of life （QoL） scores and adverse events （AEs） were analysed. Of the 175 enrolled patients, 132 completed the study. Sixty-seven patients had BMI 〉23 kg m-2, and 43 had WC 〉90 cm. Obese patients represented by WC 〉90 cm or BMI≥ 23 kg m-2 had a significantly greater prostate volume compared with non-obese patients at baseline. Total IPSS was significantly higher in the WC 〉90 cm group compared to the WC ≤ 90 cm group. Total I PSS was positively correlated with prostate volume （P=-0.031） and WC （P=0.045）. All groups showed significant improvements in total IPSS and QoL at 12 weeks. However, the improvement of total IPSS was greater in the high-BMI and high-WC groups. The most frequent AE was dizziness （n= 13）, and it was significantly lower in the obese BPH patients. Obesity was associated with increased prostate volume and lower urinary tract symptoms. Alpha-blockers appear to be efficacious for controlling symptoms, especially in obese men.

关键词： Alpha-blocker benign prostatic hyperplasia body mass index prostate waist circumference

Nonlinear Local Lyapunov Exponent and Quantification of Local Predictability

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Chinese Physics Letters 2008年第5期25卷 1919-1922页

作者：丁瑞强李建平 ha kyung-Ja State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 Division of Earth Environmental ~System Pusan National University Busan 609- 735 Korea

Nonlinear local Lyapunov exponent （NLLE） is applied to quantitatively determine the local predictability limit of chaotic systems. As an example, we find that the local predictability limit of Henon attractor varies considerably with time, and some underlying phase-spatial structure does not appear. The local predictability limit of initially adjacent points in phase space may be completely different. This will cause difficulties in making the long-time analogue forecast.

关键词： ATMOSPHERIC PREDICTABILITY

Favorable surgical treatment outcomes for chronic constipation with features of colonic pseudo-obstruction

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World Journal of Gastroenterology 2012年第32期18卷 4441-4446页

作者： Eon Chul han Heung-Kwon oh Heon-Kyun ha Eun kyung Choe Sang Hui Moon Seung-Bum Ryoo Kyu Joo Park Department of Surgery Seoul National University College of MedicineSeoul 110-744South Korea Seoul National University Hospital Gangnam Center Seoul 110-744South Korea

AIM:To determine long-term outcomes of surgical treatments for patients with constipation and features of colonic ***:Consecutive 42 patients who underwent surgery for chronic constipation within the last 13 years were prospectively *** identified a subgroup with colonic pseudo-obstruction(CPO) features,with dilatation of the colon proximal to the narrowed transitional zone,in contrast to typical slowtransit constipation(STC),without any dilated colonic *** outcomes of surgical treatments for chronic constipation with features of CPO were analyzed and compared with outcomes for ***:Of the 42 patients who underwent surgery for constipation,33 patients had CPO with dilatation of the colon proximal to the narrowed transitional *** were 16 males and 17 females with a mean age of 51.2 ± 16.1 *** had symptoms of chronic intestinal obstruction,including abdominal distension,pain,nausea,or vomiting,and the mean duration of symptoms was 67 mo(range:6-252 mo).Preoperative defecation frequency was 1.5 ± 0.6 times/wk(range:1-2 times/wk).Thirty-two patients underwent total colectomy,and one patient underwent diverting transverse *** was no surgery-related *** histologic examination showed hypoganglionosis or agangliosis in 23 patients and hypoganglionosis combined with visceral neuropathy or myopathy in 10 *** contrast,histology of STC group revealed intestinal neuronal dysplasia type B(n = 6) and visceral myopathy(n = 3).Early postoperative complications developed in six patients with CPO;wound infection(n = 3),paralytic ileus(n = 2),and intraabdominal abscess(n = 1).Defecation frequencies 3 mo after surgery improved to 4.2 ± 3.2 times/d(range:1-15 times/d).Long-term follow-up(median:39.7 mo) was available in 32 patients;all patients had improvements in constipation symptoms,but two patients needed intermittent medication for management of *** 32 patients had distinct

关键词： Constipation Total colectomy Pseudoobstruction Surgical outcome Hypoganglionosis

Comparative detection of syndecan-2 methylation in preoperative and postoperative stool DNA in patients with colorectal cancer

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World Journal of Gastrointestinal Surgery 2023年第9期15卷 2032-2041页

作者： Ji Hyeong Song Tae Jeong oh Sungwhan An kyung ha Lee Ji Yeon Kim Jin Soo Kim Department of Surgery Chungnam National University Sejong HospitalSejong 30099South Korea Genomictree Inc.Daejeon 34027South Korea Department of Surgery College of MedicineChungnam National UniversityDaejeon 35015South Korea

BACKGROUND Early detection of colorectal cancer(CRC)is essential to reduce cancer-related morbidity and *** DNA(sDNA)testing is an emerging method for early CRC ***-2(SDC2)methylation is a potential biomarker for the sDNA *** DNA methylation is an early epigenetic event during tumorigenesis and can occur in the normal colonic mucosa during aging,which can compromise the sDNA test *** In this prospective study,we enrolled 151 patients with CRC who underwent curative surgical resection between September 2016 and May *** stool samples were collected from 123 patients and postoperative samples were collected from 122 patients.A total of 104 samples were collected from both preoperative and postoperative *** promoter methylation of SDC2 in sDNA was assessed using linear target enrichment quantitative methylation-specific real-time polymerase chain *** parameters were analyzed using the results of SDC2 *** Detection rates of SDC2 methylation in the preoperative and postoperative stool samples were 88.6%and 19.7%,*** tumor size(3 cm,P=0.019)and advanced T stage(T3–T4,P=0.033)were positively associated with the detection rate of SDC2 methylation before *** sex was associated with false positives after surgery(P=0.030).Cycle threshold(CT)values were significantly decreased postoperatively compared with preoperative values(Phat the SDC2 methylation test for sDNA has acceptable sensitivity and ***,small size and early T stage tumors are associated with a low detection rate of SDC2 *** the cycle threshold values significantly decreased after surgery,SDC2 methylation test for sDNA might have a diagnostic value for CRC.

关键词： Biomarkers DNA methylation Syndecan-2 Colorectal cancer

In situ synthesis of chemically bonded NaTi2（PO4）3/rGO 2D nanocomposite for high-rate sodium-ion batteries

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Nano Research 2016年第6期9卷 1844-1855页

作者： ha-kyung Roh Hyun-kyung Kim Myeong-Seong Kim Dong-Hyun Kim kyung Yoon Chung Kwang Chul Roh Kwang-Bum Kim Department of Material Science & Engineering Yonsei University 50 Yonsei-ro Seodaemun-gu Seou103722 Republic of Korea Department of Materials Science and Metallurgy University of Cambridge 27 Charles Babbage Road Cambridge CB30FS UK Center for Energy Convergence Korea Institute of Science and Technology 5 Hwarang-ro 14-gil Seongbuk-gu Seou102792 Republic of Korea Energy & Environmental Division Korea Institute of Ceramic Engineering & Technology 101 Soho-ro Jinju-si Gyeongsangnam-do 52851 Republic of Korea

A phase-pure NaTi2（PO4）3/reduced graphene oxide （rGO） nanocomposite was prepared using a microwave-assisted one-pot method and subsequent heat treatment. The well-crystallized NaTi2（PO4）3 nanoparticles （30-40 nm） were uniformly precipitated on rGO templates through Ti-O-C bonds. The chemical interactions between the NaTi2（PO4）3 nanoparticles and rGO could immobilize the NaTi2（PO4）3 nanoparticles on the rGO sheets, which might be responsible for the excellent electrochemical performance of the nanocomposite. The NaTi2（PO4）B/rGO nanocomposite exhibited a specific capacity of 128.6 mA-h.g-1 approaching the theoretical value at a 0.1 C-rate with an excellent rate capability （72.9% capacity retention at 50 C-rate） and cycling performance （only 4.5% capacity loss after 1,000 cycles at a high rate of 10 C）. These properties were maintained even when the electrodes were prepared without the use of an additional conducting agent. The excellent sodium storage properties of the NaTi2（PO4）B/rGO nanocomposite could be attributed to the nano-sized NaTi2（PO4）3 particles, which significantly reduced the transport lengths for Na＋ ions, and an intimate contact between the NaTi2（PO4）3 particles and rGO due to chemical bonding.

关键词： NaTi2(PO4)dreducedgraphene oxide (rGO)nanocomposite chemical bonding energy-efficiency in situ synthesis high-rate sodium-ion batteries