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Evaluation of Heavy Rainfall Model Forecasts over the Korean Peninsula Using Different Physical Parameterization Schemes and Horizontal Resolution

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Advances in Atmospheric Sciences 2011年第6期28卷 1233-1245页

作者： Jeong-Gyun PARK dong-Kyou LEE Atmospheric Sciences Program School of Earth and Environmental Sciences Seoul National University Seoul 151-747 Korea

In this study, the accuracy of a Pennsylvania State University–National Center for Atmospheric Research mesoscale model （PSU/NCAR MM5） for predicting heavy summer precipitation over the Korean Peninsula was investigated. A total of 1800 simulations were performed using this model for 30 heavy rainfall events employing four cumulus parameterization schemes （CPS）, two grid-scale resolvable precipitation schemes （GRS）, and two planetary boundary layer （PBL） schemes in three model resolutions （90 km, 30 km, and 10 km）. The heavy rainfall events were mesoscale convective systems developed under the influence of mid-latitude baroclinic systems with low-level moisture transport from the ocean. The predictive accuracy for maximum rainfall was approximately 80% for 10-km resolution and was 60% for 30-km resolution. The predictive accuracy for rainfall position extended to ～150 km from the observed position for both resolutions. Simulated rainfall was most sensitive to CPS, then to PBL schemes, and then to GRS. In general, the Grell （GR） scheme and the Anthes and kuo （AK） scheme showed a better prediction capability for heavy rainfall than did the Betts-Miller （BM） scheme and the Kain-Fritsch （KF） scheme. The GR scheme also performed well in the 24-h and 12-h precipitation predictions： the parameterized convective rainfall in GR is directly related to synoptic-scale forcing. The models without CPS performed better for rainfall amounts but worse for rainfall position than those with CPS. The MM5 model demonstrated substantial predictive capacity using synoptic-scale initial conditions and lateral boundary data because heavy summer rainfall in Korea occurs in a strong synoptic-scale environment.

关键词： heavy rainfall mesoscale convection mesoscale model evaluation convective parameterization

Development of a low-background neutron detector array

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Nuclear Science and Techniques 2022年第4期33卷 10-18页

作者： Yu-Tian Li Wei-Ping Lin Bing-Shui Gao Han Chen Hao Huang Yu Huang Tao-Yu Jiao kuo-Ang Li Xiao-dong Tang Xin-Yu Wang Xiao Fang Han-Xiong Huang Jie Ren Long-Hui Ru Xi-Chao Ruan Ning-Tao Zhang Zhi-Chao Zhang CAS Key Laboratory of High Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Radiation Physics and Technology of the Ministry of Education Institute of Nuclear Science and TechnologySichuan UniversityChengdu 610064China Joint Department for Nuclear Physics Lanzhou University and Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China China Institute of Atomic Energy Beijing 102413China

A low-background neutron detector array was developed to measure the cross section of the ^(13)C(a,n)^(16)O reaction,which is the neutron source for the s-process in AGB stars,in the Gamow window(E_(c.m.)=190±40 keV)at the China Jinping Underground Laboratory(CJPL).The detector array consists of 24^(3)He proportional counters embedded in a polyethylene *** to the deep underground location and a borated polyethylene shield around the detector array,a low background of 4.5(2)/h was *** ^(51)V(p,n)^(51)Cr reaction was used to determine the neutron detection efficiency of the array for neutrons with energies E_(n)<1 ***4 simulations are shown to effectively reproduce the experimental *** were used to extrapolate the detection efficiency to higher energies for neutrons emitted in the ^(13)C(α,n)^(16)O *** theoretical angular distributions of the ^(13)C(α,n)^(16)O reaction were shown to be important in the estimation of the uncertainties of the detection efficiency.

关键词： Underground laboratory Neutron detector Low background ^(3)He Counter

Preparation and Properties of Alumina Heat Insulation Materials with High Purity

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China's Refractories 2015年第4期24卷 18-22页

作者： WANG Gang YUAN Bo WU Haibo dong Binbin HAN Jianshen CHEN kuo LI Hongxia State Key Laboratory of Advanced Refractories Sinosteel Luoyang Institute of Refractories Research Co.Ltd. State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of Sciences

With the wide using of transparent alumina ceramics and synthetic sapphire, the demand of the furnace for them is promoted steadily, and the furnace lining materials are upgrading. Having low thermal conductivity and the same composition with transparent alumina ceramics and sapphire, porous alumina ceramics with. high purity are expected to lower the high energy consumption without contamination, in this paper, porous alumina ceramics with porosity of 75.3% -81.9% and impurity less than 0. 1% were prepared by a foaming method combined with gelcasting, using high purity alumina powders as raw materials. By changing the amount of foaming agent and the solid content, the microstructure and properties of porous ceramics were tailored. The compressive strength of the porous ceramics ranged .front （ 22.4 ±2.5） MPa to （48. 1± 3. 1 ） MPa, the thermal conductivity of porous ceramics at 1 000℃ ranged between 0. 41 -0. 65 W · （ m · K）^-1.

关键词： foaming high purity alumina porous ceramics microstructure thermal conductivity

长江口深水航道及横沙东滩促淤圈围对滞流点的影响

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同济大学学报（自然科学版） 2017年第11期45卷 1621-1628页

作者：匡翠萍董智超陈括刘旭同济大学土木工程学院上海200092

滞流点位置的变化对河口拦门沙的形成和泥沙淤积具有极大的影响.基于MIKE3软件建立长江口水动力和盐度输运三维数学模型,采用实测资料对模型的潮位、流速、流向和盐度进行验证.运用验证好的数学模型模拟和分析长江口深水航道工程及横沙... 详细信息

滞流点位置的变化对河口拦门沙的形成和泥沙淤积具有极大的影响.基于MIKE3软件建立长江口水动力和盐度输运三维数学模型,采用实测资料对模型的潮位、流速、流向和盐度进行验证.运用验证好的数学模型模拟和分析长江口深水航道工程及横沙东滩促淤圈围工程对河口滞流点位置的影响,结果表明,(1)应用改进的近底层平均单宽通量计算公式确定滞流点的位置,验证结果良好,可以用该公式确定滞流点的位置;(2)深水航道工程的建设增大了水深和涨落潮流速,各汊道内落潮流量的增加明显高于涨潮流量的增加,且滞流点均向下游移动;(3)横沙东滩促淤圈围工程建成后,北港滞流点向下游移动约5km,北槽和南槽的滞流点则向上游移动约1km.

关键词：长江口深水航道横沙东滩促淤圈围滞流点数学模型

Short- and Long-term Outcomes in Patients with Connective Tissue Diseases Undergoing Percutaneous Coronary Intervention

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Chinese Medical Journal 2016年第7期129卷 804-808页

作者： Li Zhou Hui Chen Wei-Ping Li Hong-Li Gao dong-Bao Li Hui-Qiang Zhao Oao-kuo Yao Hong-Wei Li Department of Cardiology Beijing Friendship Hospital Capital Medical University Beijing 100050 China

Background： Coronary artery disease （CAD） is a leading cause of morbidity and mortality in patients with connective tissue diseases （CTDs）. Risk factors and clinical characteristics in these patients are not equivalent to those in traditional CAD patients. The objective of this study was to report short- and long-term clinical outcomes in a consecutive series of patients with CTD who underwent percutaneous coronary intervention （PC1） with stent implantation. Methods： The study group comprised 106 consecutive patients with CTD who underwent PCI in Beijing Friendship Hospital between January 2009 and June 2012. Medical records were analyzed retrospectively including clinical basic material, coronary angiogram data, and the incidence of major adverse cardiac events （MACEs） during the short- and long-term （median 3 years） follow-up. Results： Ninety-two of the patients （86.8%） had one or more traditional CAD risk lhctors. Multivessel disease was present in more than 2/3 of patients （73.6%）. Tbe left anterior descending coronary artery was the most commonly affected vessel （65. 1%）. Five bare-metal stents and 202 drug-eluting stents were implanted. After a median follow-up period of 36 months, thirteen patients （12.3%） died from cardiac causes, the rate of stent thrombosis was 9.4%, and the rate of target vessel revascularization （TVR） was 14.2%. Multivariate analysis revealed that hypertension （hazard ratio [HR] = 3.07, 95% confidence interval [CI]： 1.30-7.24, P = 0.041 ）, anterior myocardial infarction （HR - 2.77. 95% CI： 1.06-7.03, P = 0.04）, longer duration of steroid treatment （HR - 3.60, 95% CI： 1.43-9.08, P 0.032）, and C-reactive protein level 〉10 mg/L （HR 3.98, 95% CI： 1.19 12.56, P = 0.036） were independent predictors of MACEs. Conclusions： Patients with CTD and CAD may have severe coronary lesions. PCI in these patients tends to result in an increased rate of stent thrombosis and TVR during long-term follow-up, which may be influenced by traditional and nontradi

关键词： Connective Tissue Disease Coronary Artery Disease Percutaneous Coronary Intervention

An anatomical and histological study of human meniscal horn bony insertions and peri-meniscal attachments as a basis for meniscal transplantation

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Chinese Medical Journal 2009年第5期122卷 536-540页

作者： WANG Yong-jian YU Jia-kuo LUO Hao YU Chang-long AO Ying-fang XIE Xing JIANG dong ZHANG Ji-ying Institute of Sports Medicine Peking University Third Hospital Beijing 100191 China

Background AIIograft meniscal transplantation is an increasingly popular treatment option for the symptomatic young patients with meniscus deficiency. However, many questions still surround it. In this research, we studied the anatomical location and histological structure of human meniscal horn bony insertions and to observe the anatomical morphology and histomorphology of peri-meniscal attachments based on meniscal allograft transplantation. Methods Twenty-two fresh-frozen adult cadaver knees were dissected. The locations of meniscal anterior and posterior horn bony insertions to tibia were measured. The anatomical morphology of peri-meniscal attachments was observed and the histological structure of meniscal horn bony insertions and peri-meniscal attachment were studied by HE staining. Results The anterior horn bony insertion of medial meniscus was （9.19±1.83） mm inferior to the corresponding anterior border of tibial plateau, and （7.81±2.25） mm lateral to the axial line of the medial intercondylar eminence. The posterior horn bony insertion of medial meniscus was in the posterior intercondylar fossa of tibia, located between the anterior fibers of the posterior cruciate ligament （PCL） tibial insertion and anterior border of the tibial posterior intercondylar fossa, and was （5.05±1.18） mm lateral to the axial line of the medial intercondylar eminence. The distance between anterior and posterior horn bony insertions of the lateral meniscus was （13.68±2.19） mm. Anterior horn bony insertion of the lateral meniscus was （3.99±1.27） mm medial to the axial line of the lateral intercondylar eminence, and the posterior horn bony insertion of the lateral meniscus was （5.80±1.36） mm medial to the axial line of the lateral intercondylar eminence. Except for the meniscal horn bony insertions, which is the typical enthesis, we call the attachment of the other parts of menisci as ‘peri-meniscal attachment＇. The morphological and histological study showed that the main peri-meni

关键词： anatomy meniscus transplantation knee

An investigation of ab initio shell-model interactions derived by no-core shell model

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Science China(Physics,Mechanics & Astronomy) 2016年第9期59卷 52-58页

作者： XiaoBao Wang GuoXiang dong QingFeng Li CaiWan Shen ShaoYing Yu School of Science Huzhou University

The microscopic shell-model effective interactions are mainly based on the many-body perturbation theory （MBPT）, the first work of which can be traced to Brown and kuo＇s first attempt in 1966, derived from the Hamada-Johnstou nucleon-nucleon potential. However, the convergence of the MBPT is still unclear. On the other hand, ab initio theories, such as Green＇s function Monte Carlo （GFMC）, no-core shell model （NCSM）, and coupled-cluster theory with single and double excitations （CCSD）, have made many progress in recent years. However, due to the increasing demanding of computing resources, these ab initio applications are usually limited to nuclei with mass up to A = 16. Recently, people have realized the ab initio construction of valence-space effective interactions, which is obtained through a second-time renormalization, or to be more exactly, projecting the full-many- body Hamiltonian into core, one-body, and two-body cluster parts. In this paper, we present the investigation of such ab initio shell-model interactions, by the recent derived sd-shell effective interactions based on effective J-matrix Inverse Scattering Potential （JISP） and chiral effective-field theory （EFT） through NCSM. In this work, we have seen the similarity between the ab initio shell- model interactions and the interactions obtained by MBPT or by empirical fitting. Without the inclusion of three-body （3-bd） force, the ab initio shell-model interactions still share similar defects with the microscopic interactions by MBPT, i.e., T = 1 channel is more attractive while T = 0 channel is more repulsive than empirical interactions. The progress to include more many-body correlations and 3-bd force is still badly needed, to see whether such efforts of ab initio shell-model interactions can reach similar precision as the interactions fitted to experimental data.

关键词： shell model effective interactions ab initio methods

φ-pH diagram of As-N-Na-H_2O system for arsenic removal during alkaline pressure oxidation leaching of lead anode slime

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Transactions of Nonferrous Metals Society of China 2017年第3期27卷 676-685页

作者： Yun-long HE Rui-dong XU Shi-wei HE Han-sen CHEN kuo LI Yun ZHU Qing-feng SHEN Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology Kunming 650093 China State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and Technology Kunming 650093 China

In order to illustrate the thermodynamic characteristics of arsenic during alkaline pressure oxidation leaching process oflead anode slime(NaNO3as oxidant;NaOH as alkaline reagent),theφ-pH diagrams of As-Na-H2O,N-H2O,As-N-Na-H2Osystems at ionic mass concentration of0.1mol/kg and temperatures of298,373,423and473K were established according tothermodynamic *** results show that the existence forms of arsenic are associated with pH value,which mainly exists inthe forms of H3AsO4,24H AsO-,24HAsO-,H2AsO2-and As2O3in lower pH region,while it mainly exists in the form of3AsO4-when pH>*** alkali concentration and high temperature are advantageous to the arsenic *** alkaline pressureoxidation leaching experiments display that the tendency of arsenic leaching rate confirms the thermodynamic analysis resultsobtained from theφ-pH diagrams of As-N-Na-H2O system,and the highest leaching rate of arsenic reaches95.85%at453K.

关键词： φ-pH diagram As-N-Na.H2O system lead anode slime leaching arsenic removal

Trustworthiness Evaluation for Permissioned Blockchain-Enabled Applications

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Computers, Materials & Continua 2022年第11期73卷 2731-2755页

作者： Shi-Cho Cha Chuang-Ming Shiung Wen-Wei Li Chun-Neng Peng Yi-Hsuan Hung kuo-Hui Yeh Department of Information Management National Taiwan University of Science and TechnologyTaiwanChina Department of Information Management National Dong Hwa UniversityHualienTaiwanChina Department of Computer Science and Engineering National Sun Yat-Sen UniversityKaohsiungTaiwanChina

As permissioned blockchain becomes a common foundation of blockchain-based circumstances for current organizations,related stakeholders need a means to assess the trustworthiness of the applications involved *** is extremely important to consider the potential impact brought by the Blockchain technology in terms of security and ***,this study proposes a rigorous security risk management framework for permissioned blockchain-enabled *** framework divides itself into different implementation domains,i.e.,organization security,application security,consensus mechanism security,node management and network security,host security and perimeter security,and simultaneously provides guidelines to control the security risks of permissioned blockchain applications with respect to these security *** addition,a case study,including a security testing and risk evaluation on each stack of a specific organization,is demonstrated as an implementation instruction of our proposed risk management *** to the best of our knowledge,this study is one of the pioneer researches that provide a means to evaluate the security risks of permissioned blockchain applications from a holistic point of *** users can trust the applications that adopted this framework,this study can contribute to the adoption of permissioned blockchain-enabled ***,application providers can use the framework to perform gap analysis on their existing systems and controls and understand the risks of their applications.

关键词： Permissioned blockchain blockchain security blockchain risk evaluation