检索结果-南通市图书馆

Statistical Guidance on Seasonal Forecast of Korean Dust Days over South Korea in the Springtime

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2013年第5期30卷 1343-1352页

作者： keon Tae SOHN Pusan National University

This study aimed to develop the seasonal forecast models of Korean dust days over South Korea in the springtime. Forecast mode was a ternary forecast （below normal, normal, above normal） which was classified based on the mean and the standard deviation of Korean dust days for a period of 30 years （1981-2010）. In this study, we used three kinds of monthly data： the Korean dust days observed in South Korea, the National Center for Environmental Prediction in National Center for Atmospheric Research （NCEP/NCAR） reanalysis data for meteorological factors over source regions of Asian dust, and the large-scale climate indices offered from the Climate Diagnostic Center and Climate Prediction Center in NOAA. Forecast guidance consisted of two components; ordinal logistic regression model to generate trinomial distributions, and conversion algorithm to generate ternary forecast by two thresholds. Forecast guidance was proposed for each month separately and its predictability was evaluated based on skill scores.

关键词： Korean dust days ternary forecast logistic regression NCEP/NCAR reanalysis data largescale climate indices

Gut microbiome:a balancing act between degeneration and regeneration

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2022年第9期17卷 1967-1968页

作者： Nitin Saksena Matt keon OMICS Centre of Excellence G42 HealthcareMasdar CityAbu Dhabi.UAE.And Victoria UniversityMelbourneAustralia GeneiUS DarlinghurstSydneyAustralia

In a symbiotic and mutualistic manner,the gut microbiota strongly influences many vital aspects of host physiology,biology,repair,and *** role of microbiota in many areas of regenerative medicine is just beginning to emerge,but it is under-recognized because of its *** we remove the barriers that impede our understanding of this complex entity,we will uncover some of the most vital facets of our microbiome that make us who we are,its intrinsic connection with not only our wellbeing,but also with regeneration *** will subsequently define its utility in regenerative medicine.

关键词： degeneration mutual remove

Effect of change of sand properties on travel distance of ricocheted debris

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2021年第4期17卷 1486-1495页

作者： Yoon keon Kim Woo Chun Choi Department of Mechanical Engineering Korea University145 Anam-roSeongbuk-guSeoul02841Republic of Korea

The debris from exploded buildings can ricochet after colliding with the ground,thus increasing the debris travel distance and danger from any associated impacts or *** reduce this danger,the travel distance of ricocheted debris must be accurately *** study analyzed the change in the travel distance of ricocheted concrete debris relative to changes in the properties of a sand *** shear tests were conducted to measure the change in internal friction angle as a function of temperature and water content of the *** element analysis(FEA)was then applied to these variables to predict the speed and angle of the debris after *** FEA results were compared with results of low-speed ricochet experiments,which employed variable temperature and water *** travel distance of the debris was calculated using MATLAB,via trajectory equations considering the drag *** the internal friction angle decreased,the shear stress decreased,leading to deeper penetration of the debris into the *** the loss of kinetic energy increased,the velocity and travel distance of the ricocheted debris *** in the ricochet velocity and travel distance of the debris,according to changes in the internal friction angle,indicated that the debris was affected by the environment.

关键词： Ricochet Exploded debirs Environmental change Sand Temperature Water content Internal friction angle Travel distance

Development of hyaluronic acid-based edible film for alleviating dry mouth

在线全文

学校读者我要写书评

暂无评论

Food Science and Human Wellness 2023年第2期12卷 371-377页

作者： Dong-keon Kweon Jung-Ah Han Jinwoo Bio Co. Ltd.Yongin 17111Korea Department of Food and Nutrition Sangmyung UniversitySeoul 03016Korea

For alleviating dry mouth symptoms,edible films based on hyaluronic acid(HA)with 3 different m(800,1200 and 2300 kDa)were prepared(800 F,1200 F and 2300 F,respectively),and the properties as well as effectiveness were *** concentration of each HA dispersion for film forming was set as 3.0%,1.5%or 1.0%,for the m800,1200 and 2300 kDa,respectively,based on the *** 800 F showed the highest thickness,tensile strength,and water vapor transparency,whereas obtained the lowest transparency and elongation at break among *** of the HA films showed safety against microorganism during 28 storage day at 40℃with 60%*** optimum site for film attachment in mouth was the palate,and800 F was the most effective for stimulating saliva secretion,eliciting a 38%increase compared to control(without film),tested by the elderly over 65 years *** the sensory test,800 F was also the most *** on above results,the edible films effectively stimulating saliva secretion could be produced with HA,and the physical,sensory characteristics as well as disintegration times of the film could be controlled by mand the dissolution concentration of HA.

关键词： Edible film Hyaluronic acid Saliva stimulating Tensile strength Thickness

Prediction of Monthly Mean Surface Air Temperature in a Region of China

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2007年第3期24卷 503-508页

作者： Jeong-Hyeong LEE keon-Tae SOHN Division of Management Information Science Dong-A University Busan 604-714Korea Department of Statistics Pusan National University Busan 609-735Korea

In conventional time series analysis, a process is often modeled as three additive components： linear trend, seasonal effect, and random noise. In this paper, we perform an analysis of surface air temperature in a region of China using a decomposition method in time series analysis. Applications to the National Centers for Environmental Prediction/the National Center for Atmospheric Research （NCEP/NCAR） Collaborative Reanalysis data in this region of China are discussed. The main finding was that the surface air temperature trend estimated for January 1948 to February 2006 was not statistically significant at 0.5904℃ （100 yr）^-1. Forecasting aspects are also considered.

关键词： Chinese region surface air temperature time series decomposition method regression

Guidance on the Choice of Threshold for Binary Forecast Modeling

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2008年第1期25卷 83-88页

作者： keon Tae SOHN Sun Min PARK Department of Statistics Pusan National University

This paper proposes useful guidance on the choice of threshold for binary forecasts. In weather forecast systems, the probabilistic forecast cannot be used directly when estimated too smoothly. In this case, the binary forecast, whether a meteorological event will occur or not, is preferable to the probabilistic forecast. A threshold is needed to generate a binary forecast, and the guidance in this paper encompasses the use of skill scores for the choice of threshold according to the forecast pattern. The forecast pattern consists of distribution modes of estimated probabilities, occurrence rates of observations, and variation modes. This study is performed via Monte-Carlo simulation, with 48 forecast patterns considered. Estimated probabilities are generated by random variate sampling from five distributions separately. Varying the threshold from 0 to 1, binary forecasts are generated by threshold. For the assessment of binary forecast models, a 2×2 contingency table is used and four skill scores （Heidke skill score, hit rate, true skill statistic, and threat score） are compared for each forecast pattern. As a result, guidance on the choice of skill score to find the optimal threshold is proposed.

关键词： binary forecast Monte-Carlo simulation threshold skill score

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

在线全文

学校读者我要写书评

暂无评论

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

Properties of ZnO Thin Films Grown on Si (100) Substrates by Pulsed Laser Deposition

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2010年第11期26卷 973-976页

作者： Young Rae Jang keon-Ho Yoo Seung Min Park Department of Physics Kyung Hee University Department of Chemistry Kyung Hee University

ZnO thin films were grown on Si （100） substrates by pulsed laser deposition using a ZnO *** substrate temperature was varied in the range of room temperature to 800 ℃,and the oxygen partial pressure of 0.1333 Pa （1 m Torr） to 1333 Pa （10 Torr）.The properties of the resulting films were investigated by photoluminescence （PL）,grazing incidence X-ray diffraction （GIXRD）,X-ray photoelectron spectroscopy （XPS）,and field emission scanning electron microscopy （FESEM）.Based on the ultraviolet （UV,～380 nm） to visible emission ratio in the PL spectrum,the optimum growth conditions were determined to be 600 ℃ and 133.3 Pa （1 Torr）,*** oxygen 1s peak in the XPS spectrum was decomposed into two *** peak at lower binding energy increased in intensity with the oxygen partial pressure from 0.1333 Pa （1 m Torr） to 133.3 Pa （1 Torr） while the other peak *** GIXRD curve at the optimum condition showed strong two peaks （002） and （103）.A strong correlation between the （103） peak intensity and the UV emission intensity was found.

关键词： ZnO Pulsed laser deposition Photoluminescence

Climate Change Signal Analysis for Northeast Asian Surface Temperature

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2005年第2期22卷 159-171页

作者： Jeong-HyeongLEE ByungsooKIM keon-TaeSOHN Won-TaeKOWN Seung-KiMIN DivisionofManagementInformationScience Dong-AUniversityBusan604-714 DepartmentofDataScience InjeUniversityKimhae621-749 DepartmentofStatistics PusanNationalUniversityBusan609-735 ClimateResearchLaboratory MeteorologicalResearchInstituteKoreanMeteorologicalAdministrationSeoul156-720 ClimateResearchLaboratory MeteorologicalResearchInstituteKoreanMeteorologicalAdministrationSeoul156-720／／MeteorologicalInstituteoftheUniversityofBonnGermany

Climate change detection, attribution, and prediction were studied for the surface temperature in the Northeast Asian region using NCEP/NCAR reanalysis data and three coupled-model simulations from ECHAM4/OPYC3, HadCM3, and CCCma GCMs (Canadian Centre for Climate Modeling and Analysis general circulation model). The Bayesian fingerprint approach was used to perform the detection and attribution test for the anthropogenic climate change signal associated with changes in anthropogenic carbon dioxide (CO2) and sulfate aerosol (SO42-) concentrations for the Northeast Asian temperature. It was shown that there was a weak anthropogenic climate change signal in the Northeast Asian temperature change. The relative contribution of CO2 and SO42- effects to total temperature change in Northeast Asia was quantified from ECHAM4/OPYC3 and CCCma GCM simulations using analysis of variance. For the observed temperature change for the period of 1959-1998, the CO2 effect contributed 10%-21% of the total variance and the direct cooling effect of SO42- played a less important role (0%-7%) than the CO2 effect. The prediction of surface temperature change was estimated from the second CO2+SO42- scenario run of ECHAM4/OPYC3 which has the least error in the simulation of the present-day temperature field near the Korean Peninsula. The result shows that the area-mean surface temperature near the Korean Peninsula will increase by about 1.1° by the 2040s relative to the 1990s.

关键词： climate change detection attribution prediction Northeast Asia