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Examination of n-t_(9) conditions required by N=50,82,126 waiting points in r-process

Communications in theoretical Physics 2021年第10期73卷 147-157页

作者： Nguyen Duy Ly Nguyen Ngoc Duy Nguyen kim Uyen Vinh N t Pham Faculty of Fundamental Sciences Vanlang UniversityHo Chi Minh City 700000Vietnam Department of Physics Sungkyunkwan UniversitySuwon 16419Republic of Korea Department of Physics Ho Chi Minh City University of EducationHo Chi Minh City 700000Vietnam

We examined the conditions of neutron density(n) and temperature(t9) required for the N = 50, 82,and 126 isotopes to be waiting points(WP) in the r-process. the nuclear mass based on experimental data presented in the AME2020 database(AME and AME ± Δ) and that predicted using FRDM,WS4, DZ10, and ktUY models were employed in our estimations. We found that the conditions required by the N = 50 WP significantly overlap with those required by the N = 82 ones, except for the WS4 model. In addition, the upper(or lower) bounds of the n-t9 conditions based on the models are different from each other due to the deviations in the two-neutron separation *** standard deviations in the nuclear mass of 108 isotopes in the three N = 50, 82, and 126 groups are about rms = 0.192 and 0.434 Me V for the pairs of ktUY-AME and WS4-ktUY models,respectively. We found that these mass uncertainties result in a large discrepancy in the nn-t_(9) conditions, leading to significant differences in the conditions for simultaneously appearing all the three peaks in the r-process abundance. the newly updated FRDM and WS4 calculations can give the overall conditions for the appearance of all the peaks but vice versa for their old versions in a previous study. the change in the final r-process isotopic abundance due to the mass uncertainty is from a few factors to three orders of magnitude. therefore, accurate nuclear masses of the r-process key nuclei, especially for 76 Fe,81Cu,127Rh,132Cd,192Dy, and 197tm, are highly recommended to be measured in radioactive-ion beam facilities for a better understanding of the r-process evolution.

关键词： neutron capture r-process nuclear mass isotopic abundance precise mass measurement

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中老年群体的BMI、久坐行为、身体活动水平、年龄歧视和老龄化焦虑的关系研究

中老年群体的BMI、久坐行为、身体活动水平、年龄歧视和老龄化焦...

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第二届陕西省体育科学大会

作者：李静 Seung-Yong kim Chae-Hee PARk

随着人口老龄化现象以惊人的速度席卷全球,各国都在积极推动健康老龄化和积极老龄化,身体活动不足和久坐行为已严重影响到人们的健康,甚至与全因死亡率和跌倒风险有关。年龄歧视和老龄化焦虑是实现健康老龄化的主要阻碍因素之一,老年人... 详细信息

随着人口老龄化现象以惊人的速度席卷全球,各国都在积极推动健康老龄化和积极老龄化,身体活动不足和久坐行为已严重影响到人们的健康,甚至与全因死亡率和跌倒风险有关。年龄歧视和老龄化焦虑是实现健康老龄化的主要阻碍因素之一,老年人的身心健康问题直接影响到整个社会的健康,是我们面临的重大课题。研究目的:调查中老年群体的BMI、久坐行为、身体活动水平,年龄歧视和老龄化焦虑的现状及其相互间的关联性,为即将步入老年阶段的中老年群体提高晚年幸福感,构建积极健康的老年生活提供基础资料。研究方法:采取随机抽样的方法于2023年在中国S地区选取264名中老年人(男性87名,女性177名)为调查对象。根据性别、BMI(kg/m2)、婚姻状况、吸烟状况、受教育程度、主观健康状况等因素分层对中老年群体的身体活动水平、年龄歧视和老龄化焦虑程度进行问卷测量。身体活动水平分为高强度(VPA)、中强度(MPA)、低强度(LP A),每次至少持续10分钟才记录为有效。数据分析使用SPSS 22.0和AMOS 25.0统计软件进行因子分析、t检验、Pearson's r、方差分析(ANOVA)和路径分析。研究结果:结果表明,61.8%的中老年群体的BMI值高于正常数值范围;中老年群体的久坐行为、身体活动水平的调查结果显示,男性的久坐行为、VPA、MPA均高于女性的水平;中老年群体的BMI与VPA呈负相关关系(r=-.148, p=.016),BMI与MPA呈负相关关系(r=-.164, p=.008),久坐行为与LPA成负相关关系(r=-.135, p=.028);中老年群体的年龄歧视与老龄化焦虑呈正相关关系(r=.539,p=.000)。结论:VPA和MPA不同程度会影响中老年群体的BMI指数,适当增加身体活动量,减少久坐行为,能有效降低老年人的BMI指数。为改善老龄化社会结构中的老龄化焦虑,实现健康老龄化,不仅需要社会结构层面的努力,还需要减少社会群体中的年龄歧视,提高个体对健康老龄化的再认识,促使中老年人为今后步入健康老年生活做好充分准备。

关键词： BMI 久坐行为身体活动年龄歧视老化焦虑

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Evaluation of the k-nearest neighbor method for forecasting the influent characteristics of wastewater treatment plant

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Frontiers of Environmental Science & Engineering 2016年第2期10卷 299-310页

作者： Minsoo kim Yejin kim Hyosoo kim Wenhua PIAO Changwon kim Department of Civil and Environmental Engineering Pusan National University Busan 609-735 Republic of Korea Department of Civil and Environmental Engineering Catholic University of Pusan Busan 609-757 Republic of Korea EnvironSoft Co. Ltd. #511 Industry-University Co.Bld. Pusan Nationai University Busan 609-735 Republic of Korea

the k-nearest neighbor （k-NN） method was evaluated to predict the influent flow rate and four water qualities, namely chemical oxygen demand （COD）, suspended solid （SS）, total nitrogen （t-N） and total phosphorus （t-P） at a wastewater treatment plant （WWtP）. the search range and approach for determining the number of nearest neighbors （NNs） under dry and wet weather conditions were initially optimized based on the root mean square error （RMSE）. the optimum search range for considering data size was one year. the square root-based （SR） approach was superior to the distance factor-based （DF） approach in determining the appropriate number of NNs. However, the results for both approaches varied slightly depending on the water quality and the weather conditions. the influent flow rate was accurately predicted within one standard deviation of measured values. Influent water qualities were well predicted with the mean absolute percentage error （MAPE） under both wet and dry weather conditions. For the seven-day prediction, the difference in predictive accuracy was less than 5% in dry weather conditions and slightly worse in wet weather conditions. Overall, the k-NN method was verified to be useful for predicting WWtP influent characteristics.

关键词： influent wastewater prediction data-drivenmodel k-nearest neighbor method (k-NN)

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Metabolic Plasticity of Nitrogen Assimilation by Porphyra umbilicalis(Linnaeus) kützing

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Journal of Ocean University of China 2012年第4期11卷 517-526页

作者： Jang k.kim George P.kraemer Charles Yarish Departments of Ecology and Evolutionary Biology and Marine Sciences University of Connecticut1 University PlaceStamfordCT 06901USA Department of Environmental Studies Purchase College735 Anderson Hill RoadPurchaseNY 10577USA

the physical stresses associated with emersion have long been considered major factors determining the vertical zona- tion of intertidal seaweeds. We examined Porphyra umbilicalis （Linnaeus） kiitzing thalli from the vertical extremes in elevation of an intertidal population （i.e. upper and lower intertidal zones） to determine whether Porphyra thalli acclimate to different vertical elevations on the shore with different patterns of nitrate uptake and nitrate reductase （NR） and glutamine synthetase （GS） activities in response to different degrees of emersion stress. We found that the nitrate uptake and NR recovery in the emersed tissues took longer in lower intertidal sub-population than in upper intertidal sub-population; and GS activity was also significantly affected by emersion and, interestingly, such an activity was enhanced by emersion of thalli from both upper and lower intertidal zones. these results sug- gested that intta-population variability in post-emersion recovery of physiological functions such as nutrient uptake and NR activity enables local adaptation and contributes to the wide vertical distribution ofP. umbilicalis. the high GS activity during periodic emer- sion stress may be a protective mechanism enabling P umbilicalis to assimilate nitrogen quickly when it again becomes available, and may also be an evidence ofphotorespiration during emersion.

关键词： emersion glutamine synthetase nitrate reductase nitrogen assimilation Porphyra

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Low skeletal muscle mass is associated with non-alcoholic fatty liver disease in korean adults： the Fifth korea National Health and Nutrition Examination Survey

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Hepatobiliary & Pancreatic Diseases International 2016年第1期15卷 39-47页

作者： hee yeon kim chang wook kim chung-hwa park jong young choi kyungdo han anwar t merchant yong-moon park division of hepatology department of internal medicinecollege of medicinethe catholic university of korea222Banpo-daeroSeocho-guSeou1 06591Republic of Korea department of biostatistics college of medicinethe catholic university of korea222Banpo-daeroSeocho-guSeou1 06591Republic of Korea department of epidemiology and biostatistics arnold school of public healthuniversity of south carolinaColumbiaSC 29208USA epidemiology branch national institute of environmental health sciencesnational institutes of healthdepartment of health and human servicesResearch Triangle ParkNC 27709USA

BACkGROUND： Sarcopenia and non-alcoholic fatty liver dis- ease （NAFLD） share similar pathophysiological mechanisms, and the relationship between sarcopenia and NAFLD has been recently investigated. the study investigated whether low skel- etal muscle mass is differentially associated with NAFLD by gender in korean adults. MEtHODS： We conducted a cross-sectional analysis of the data from the Fifth korea National Health and Nutrition Examination Survey. the skeletal muscle index （SMI） was obtained by the appendicular skeletal muscle mass divided by the weight. NAFLD was defined as a fatty liver index （FLI）〉60 in the absence of other chronic liver disease. RESULtS： Among the included subjects, 18.3% （SE： 1.4%） in men and 7.0% （SE： 0.7%） in women were classified as having FLI-defined NAFLD. Most of the risk factors for FLI-defined NAFLD showed a significant negative correlation with the SMI in both genders. Multiple logistic regression analysis showed that low SMI was associated with FLI-defined NAFLD, inde- pendent of other metabolic and lifestyle parameters in both genders [males： odds ratio （OR）=1.35; 95% confidence inter- val （CI）： 1.17-1.54; females： OR=1.36; 95% CI： 1.18-1.55]. the magnitude of the association between FLI-defined NAFLD and low SMI was higher in middle aged to elderly males （OR-1.50; 95% CI： 1.22-1.84） than in males less than 45 years of age （OR=1.25; 95% CI： 1.02-1.52） and in premenopausal females （OR=l.50; 95% CI： 1.12-2.03） than in postmenopausal females （OR-1.36; 95% CI： 1.20-1.54）.CONCLUSIONS： Low SMI is associated with the risk of FLI- defined NAFLD independent of other well-known metabolic risk factors in both genders. this association may differ ac- cording to age group or menopausal status. Further studies are warranted to confirm this relationship.

关键词： korea National Health and Nutrition Examination Survey non-alcoholic fatty liver disease sarcopenia skeletal muscle

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techno-economic evaluation of a biogas-based oxidative coupling of methane process for ethylene production

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Frontiers of Chemical Science and Engineering 2018年第4期12卷 598-618页

作者： Alberto t.Penteado Mijin kim Hamid R.Godini Erik Esche Jens-Uwe Repke Process Dynamics and Operations Group Technische Universitat BerlinD-10623 BerlinGermany

this contribution is a preliminary techno-economic assessment of a biogas-based oxidative coupling of methane (OCM) process. Biogas is frequently utilized as a renewable energy source within small scale combined heat and power plants or as a natural gas substitute. the activation of methane also enables its utilization as a feedstock to produce chemicals. In this sense, the OCM process allows for the direct conversion of methane into ethylene, which is a major building block for the chemical and polymer industries. Biogas resulting from the anaerobic digestion of vinasse, a liquid effluent from bioethanol industry, is treated for contaminant removal and its methane content is converted into ethylene, which is then purified as the main product. the biogas cleaning process is assessed based on literature data, while an experimentally validated simulation model is used to assess the OCM process. A techno-economic evaluation is then performed through a Monte Carlo simulation, wherein uncertain parameters take random values between reasonable bounds. the net present value results positive in 74% of the cases, indicating that the project is profitable under a wide range of scenarios. Some performance improvement opportunities have been identified and highlighted to guide future studies in the topic.

关键词： biogas conversion ethylene production oxidative coupling of methane feasibility study

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Reliable and explainable machine-learning methods for accelerated material discovery

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npj Computational Materials 2019年第1期5卷 186-194页

作者： Bhavya kailkhura Brian Gallagher Sookyung kim Anna Hiszpanski t.Yong-Jin Han Center for Applied Scientific Computing Computing DirectorateLawrence Livermore National LaboratoryLivermoreCAUSA Materials Science Division Physical and Life Sciences DirectorateLawrence Livermore National LaboratoryLivermoreCAUSA

Despite ML’s impressive performance in commercial applications,several unique challenges exist when applying ML in materials science *** such a context,the contributions of this work are ***,we identify common pitfalls of existing ML techniques when learning from underrepresented/imbalanced material ***,we show that with imbalanced data,standard methods for assessing quality of ML models break down and lead to misleading ***,we find that the model’s own confidence score cannot be trusted and model introspection methods(using simpler models)do not help as they result in loss of predictive performance(reliability-explainability trade-off).Second,to overcome these challenges,we propose a general-purpose explainable and reliable machine-learning ***,we propose a generic pipeline that employs an ensemble of simpler models to reliably predict material *** also propose a transfer learning technique and show that the performance loss due to models’simplicity can be overcome by exploiting correlations among different material properties.A new evaluation metric and a trust score to better quantify the confidence in the predictions are also *** improve the interpretability,we add a rationale generator component to our framework which provides both model-level and decision-level ***,we demonstrate the versatility of our technique on two applications:(1)predicting properties of crystalline compounds and(2)identifying potentially stable solar cell *** also point to some outstanding issues yet to be resolved for a successful application of ML in material science.

关键词： explain overcome simpler

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Computational Analysis of a Variable Ejector Flow

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Journal of thermal Science 2006年第2期15卷 140-144页

作者： H.D. kim J.H. LEE t. SEtOGUCHI S.MAtSUO School of Mechanical Engineering Andong National University 388 Songchun-dong Andong 760-749 Korea Department of Mechanical Engineering Saga University 1 Honjo Saga 840-8502 Japan

the present study addresses a variable ejector which can improve the ejector efficiency and control the re-circulation ratio under a fixed operating pressure ratio. the variable ejector is a facility to obtain specific recirculation ratio under a given operating pressure ratio by varying the ejector throat area ratio. the numerical simulations are carried out to provide an understanding of the flow characteristics inside the variable ejector. the sonic and supersonic nozzles are adopted as primary driving nozzles in the ejector system, and a movable cone cylinder, inserted into a conventional ejector-diffuser system, is used to change the ejector throat area ratio. the numerical simulations are based on a fully implicit finite volume scheme of the compressible, Reynolds-Averaged Navier-Stokes equations. the results show that the variable ejector can control the recirculation ratio at a fixed operating pressure ratio.

关键词： variable ejector ejector throat area ratio re-circulation ratio

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Circadian clock component, LHY, tells a plant when to respond photosynthetically to light in nature

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Journal of Integrative Plant Biology 2017年第8期59卷 572-587页

作者： Youngsung Joo Variluska Fragoso Felipe Yon Ian t. Baldwin Sang-Gyu kim Department of Molecular Ecology Max Planck Institute for Chemical EcologyHans-Knoll-Straβe 8D-07745 JenaGermany center for genome engineering institute for basic scienceYuseong-guDaejeon34047South Korea

the circadian clock is known to increase plant growth and fitness, and is thought to prepare plants for photosynthesis at dawn and dusk; whether this happens in nature was unknown. We transformed the native tobacco, Nicotiana attenuata to silence two core clock components, NaLHY （irLHY） and NatOC1 （irtOC1）. We characterized growth and light- and dark-adapted photosynthetic rates （Ac） throughout a 24 h clay in empty vector-transformed （EV）, irLHY, and irtOC1 plants in the field, and in NaPhyA-and NaPhyB1-silenced plants in the glasshouse. the growth rates of irLHY plants were lower than those of EV plants in the field. While irLHY plants reduced Ac earlier at dusk, no differences between irLHY and EV plants were observed at dawn in the field, irLHY, but not EV plants, responded to light in the night by rapidly increasing Ac. Under controlled conditions, EV plants rapidly increased Ac in the day compared to dark-adapted plants at night; irLHY plants lost these time-dependent responses. the role of NaLHY in gating photosynthesis is independent of the light-depen- dent reactions and red light perceived by NaPhyA, but not NaPhyB1. In summary, the circadian clock allows plants not to respond photosynthetically to light at night by anticipating and gating red light-mediated in native tobacco.

关键词： in et is of Circadian clock component,LHY,tells a plant when to respond photosynthetically to light in nature were for Figure EV tOC

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tensorial tomographic Fourier ptychography with applications to muscle tissue imaging

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Advanced Photonics 2024年第2期6卷 50-60页

作者： Shiqi Xu Xi Yang Paul Ritter Xiang Dai kyung Chul Lee Lucas kreiss kevin C.Zhou kanghyun kim Amey Chaware Jadee Neff Carolyn Glass Seung Ah Lee Oliver Friedrich Roarke Horstmeyer Duke University DurhamNorth CarolinaUnited States Friedrich-Alexander University ErlangenGermany UC San Diego La JollaCaliforniaUnited States Yonsei University SeoulRepublic of Korea UC Berkeley BerkeleyCaliforniaUnited States Duke University Medical Center DurhamNorth CarolinaUnited States

We report tensorial tomographic Fourier ptychography(t^(2)oFu),a nonscanning label-free tomographic microscopy method for simultaneous imaging of quantitative phase and anisotropic specimen information in *** upon Fourier ptychography,a quantitative phase imaging technique,t^(2)oFu additionally highlights the vectorial nature of *** imaging setup consists of a standard microscope equipped with an LED matrix,a polarization generator,and a polarization-sensitive *** tensors of anisotropic samples are computationally recovered from polarized intensity measurements across three *** demonstrate t^(2)oFu’s efficiency through volumetric reconstructions of refractive index,birefringence,and orientation for various validation samples,as well as tissue samples from muscle fibers and diseased heart *** reconstructions of healthy muscle fibers reveal their 3D fine-filament structures with consistent ***,we demonstrate reconstructions of a heart tissue sample that carries important polarization information for detecting cardiac amyloidosis.

关键词： computational imaging three-dimensional imaging phase retrieval microscopy polarization-sensitive imaging labelfree imaging

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