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Omental fibroma combined with right indirect inguinal hernia masquerades as a scrotal tumor: A case report
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作者 Ping Zhou Chan-Hui Jin +6 位作者 ying shi Guo-Qing Ma Wen-Hao Wu Yu Wang Kun Cai Wu-Feng Fan Tian-Bao Wang 《World Journal of Clinical Cases》 SCIE 2024年第5期988-994,共7页
BACKGROUND The most common causes of scrotal enlargement in patients include primary tumor of the scrotum,inflammation,hydrocele of the tunica vaginalis,and indirect inguinal hernia;scrotal enlargement caused by exter... BACKGROUND The most common causes of scrotal enlargement in patients include primary tumor of the scrotum,inflammation,hydrocele of the tunica vaginalis,and indirect inguinal hernia;scrotal enlargement caused by external tumors of the scrotum is rare.The patient had both a greater omentum tumor and an inguinal hernia,and the tumor protruded into the scrotum through the hernia sac,which is even rarer.Moreover,omental tumors are mostly metastatic,and primary omental fibroma is rare.CASE SUMMARY Here,we report a rare case of a 25-year-old young man with scrotal enlargement and pain for 3 months.Preoperative examination and multidisciplinary discu-ssions considered intra-abdominal tumor displacement and inguinal hernia,and intraoperative exploration confirmed that the greater omentum tumor protruded into the scrotum.Therefore,tumor resection and tension-free inguinal hernia repair were performed.The final diagnosis was benign fibroma of the greater omentum accompanied by an indirect inguinal hernia.CONCLUSION This unusual presentation of a common inguinal hernia disease illustrates the necessity of performing detailed history taking,physical examination,and imaging before surgery. 展开更多
关键词 HERNIA Indirect inguinal hernia FIBROMA Omental tumor Scrotal tumor Greater omentum Case report
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THE LIMITING PROFILE OF SOLUTIONS FOR SEMILINEAR ELLIPTIC SYSTEMS WITH A SHRINKING SELF-FOCUSING CORE
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作者 金可 石影 谢华飞 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期583-608,共26页
In this paper,we consider the semilinear elliptic equation systems{△u+u=αQ_(n)(x)|u|^(α-2)|v|^(β)u in R^(N),-△v+v=βQ(x)|u|^(α)|v|^(β-2)v in R^(N),where N≥3,α,β>1,α+β<2^(*),2^(*)=2N/N-2 and Q_(n) are... In this paper,we consider the semilinear elliptic equation systems{△u+u=αQ_(n)(x)|u|^(α-2)|v|^(β)u in R^(N),-△v+v=βQ(x)|u|^(α)|v|^(β-2)v in R^(N),where N≥3,α,β>1,α+β<2^(*),2^(*)=2N/N-2 and Q_(n) are bounded given functions whose self-focusing cores{x∈R^(N)|Q_(n)(x)>0} shrink to a set with finitely many points as n→∞.Motivated by the work of Fang and Wang[13],we use variational methods to study the limiting profile of ground state solutions which are concentrated at one point of the set with finitely many points,and we build the localized concentrated bound state solutions for the above equation systems. 展开更多
关键词 Schrödinger system ground states solutions bound state solutions
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Specifying Requirements of Real-Time System with Rules and Templates 被引量:8
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作者 Wu Guo-qing Xiao Hai-feng +1 位作者 Zheng Pen ying shi 《Wuhan University Journal of Natural Sciences》 EI CAS 2000年第3期278-284,共7页
This paper presents a model specifying requirements of real-time systems. Different from existing researches, this model mainly uses rules and templates to represent hierarchical FSMs (Finite State Machine). In this m... This paper presents a model specifying requirements of real-time systems. Different from existing researches, this model mainly uses rules and templates to represent hierarchical FSMs (Finite State Machine). In this model, one rule corresponds to one state transition of FSM and one template corresponds to one FSM. Rules and information with respect to a FSM can be written in a template. So templates include not only state diagrams, but also information that can not be described by FSM, such as performance requirements. The specification using this model consists of a collection of templates and it is easy for users to understand and to review. After introduced the related researches and principles of the model, this paper specifies requirements of a real-time system with this model, and discusses characters of this model in the end. 展开更多
关键词 requirements specification model requirements specification real-time system finite state machine
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Theoretical study on the relationship between the position of the substituent and the ESIPT fluorescence characteristic of HPIP
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作者 张馨 韩建慧 +4 位作者 李尤 孙朝范 苏醒 石英 尹航 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第3期442-447,共6页
The influences of the substituent base position on the excited state intramolecular proton transfer fluorescence properties were explored in 2-(2'-hydroxyphenyl)imidazo[1,2-a]-pyridine(HPIP)and HPIP's derivati... The influences of the substituent base position on the excited state intramolecular proton transfer fluorescence properties were explored in 2-(2'-hydroxyphenyl)imidazo[1,2-a]-pyridine(HPIP)and HPIP's derivatives(5'Br-HPIP and 6'BrHPIP).And the density functional theory(DFT)and time-dependent DFT(TD-DFT)methods were used to calculate the molecule structures.The calculated results showed that the influence of 5'Br-HPIP on the fluorescence intensity is stronger than that of 6'Br-HPIP.The fluorescence emission peak of 5'Br-HPIP occurred a blue shift compared with HPIP,and 6'BrHPIP exhibited an opposite red shift.The change of the fluorescence emission peak was attributed to the decrease of the energy gap from 6'Br-HPIP to 5'Br-HPIP.Our work on the substituent position influence could be helpful to design and develop new materials. 展开更多
关键词 TIME-DEPENDENT density functional theory EXCITED state INTRAMOLECULAR PROTON transfer
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OCTA定量分析补阳还五汤加味对非增殖型糖尿病视网膜病变患者视盘血流的影响
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作者 石颖 陈子扬 +3 位作者 叶照达 柯发杰 胡艳红 陈胜 《国际眼科杂志》 CAS 北大核心 2023年第12期2040-2045,共6页
目的:观察补阳还五汤加味治疗气阴两虚、络脉瘀阻型非增殖型糖尿病视网膜病变(NPDR)的临床疗效,并应用光学相干断层扫描血管成像(OCTA)定量分析治疗前后视盘旁血流密度的变化。方法:采用前瞻性随机对照试验。收集2022-06/11期间我院收... 目的:观察补阳还五汤加味治疗气阴两虚、络脉瘀阻型非增殖型糖尿病视网膜病变(NPDR)的临床疗效,并应用光学相干断层扫描血管成像(OCTA)定量分析治疗前后视盘旁血流密度的变化。方法:采用前瞻性随机对照试验。收集2022-06/11期间我院收治的符合气阴两虚、络脉瘀阻型NPDR患者58例99眼,随机分为对照组29例48眼,采用2019年美国眼科学会发布的糖尿病视网膜病变推荐方案进行基础治疗(对于轻度NPDR患者进行控制血糖、糖尿病健康教育、定期随访;中度NPDR患者必要时增加局部或格栅样激光光凝治疗),观察组29例51眼在对照组的基础上加用补阳还五汤加味口服治疗1mo。比较两组患者治疗前后最佳矫正视力(BCVA)、中医证候疗效、视盘旁放射状毛细血管网血流密度(ppVD)及视盘旁视网膜神经纤维层(pRNFL)厚度变化。结果:治疗1mo后观察组BCVA(LogMAR)为0.20(0.10,0.30),较对照组0.30(0.20,0.40)明显改善(P<0.05)。治疗1mo后观察组中医证候疗效优于对照组(P<0.05)。观察组治疗1mo后各象限ppVD均较治疗前明显提高,且观察组各象限ppVD均高于对照组(P<0.05)。观察组治疗1mo后上方、颞侧象限及全周平均pRNFL厚度较治疗前升高,且观察组上方、颞侧、下方象限和全周平均pRNFL厚度均高于对照组(P<0.05)。结论:气阴两虚、络脉瘀阻型NPDR患者服用补阳还五汤加味后可改善视力、提高中医证候疗效,可能与其能提高视盘旁放射状毛细血管网血流密度和减少视盘旁神经纤维层的损伤有关。 展开更多
关键词 非增殖型糖尿病视网膜病变 补阳还五汤加味 视盘血流 光学相干断层扫描血管成像(OCTA)
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Hybrid absorbing boundary condition based on transmitting boundary and its application in 3D fractional viscoacoustic modeling
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作者 Song-Ling Li ying shi +2 位作者 Ning Wang Wei-Hong Wang Xuan Ke 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期840-856,共17页
An accurate numerical simulation for wave equations is essential for understanding of wave propagation in the earth's interior as well as full waveform inversion and reverse time migration. However, due to computa... An accurate numerical simulation for wave equations is essential for understanding of wave propagation in the earth's interior as well as full waveform inversion and reverse time migration. However, due to computational cost and hardware capability limitations, numerical simulations are often performed within a finite domain. Thus, an adequate absorbing boundary condition (ABC) is indispensable for obtaining accurate numerical simulation results. In this study, we develop a hybrid ABC based on a transmitting boundary, which is referred to as THABC, to eliminate artificial boundary reflections in 3D second-order fractional viscoacoustic numerical simulations. Furthermore, we propose an adaptive weighted coefficient to reconcile the transmitting and viscoacoustic wavefields in THABC. Through several numerical examples, we determine that the proposed THABC approach is characterized by the following benefits. First, with the same number of absorbing layers, THABC exhibits a better ability in eliminating boundary reflection than traditional ABC schemes. Second, THABC is more effective in computation, since it only requires the wavefields at the current and last time steps to solve the transmitting formula within the absorbing layers. Benefiting from a simple but effective combination between the transmitting equation and the second-order wave equation, our scheme performs well in the 3D fractional Laplacian viscoacoustic numerical simulation. 展开更多
关键词 Hybrid absorbing boundary Numerical simulation Transmitting boundary Fractional viscoacoustic wave equation
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The SMAD2/miR-4256/HDAC5/p16^(INK4a) signaling axis contributes to gastric cancer progression
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作者 MIN WANG HAILIANG ZHAO +14 位作者 WEIWEI CHEN CAIQUN BIE JINying YANG WENRUI CAI CHUTIAN WU YANFANG CHEN SHUFEN FENG ying shi YUTING LI HUIJUN TANG LIXIAN ZHONG LILIANGZI GUO SISI CHEN LINJING LONG SHAOHUI TANG 《Oncology Research》 SCIE 2023年第4期515-541,共27页
The dysregulation of exosomal microRNAs(miRNAs)plays a crucial role in the development and progression of cancer.This study investigated the role of a newly identified serum exosomal miRNA miR-4256 in gastric cancer(G... The dysregulation of exosomal microRNAs(miRNAs)plays a crucial role in the development and progression of cancer.This study investigated the role of a newly identified serum exosomal miRNA miR-4256 in gastric cancer(GC)and the underlying mechanisms.The differentially expressed miRNAs were firstly identified in serum exosomes of GC patients and healthy individuals using next-generation sequencing and bioinformatics.Next,the expression of serum exosomal miR-4256 was analyzed in GC cells and GC tissues,and the role of miR-4256 in GC was investigated by in vitro and in vivo experiments.Then,the effect of miR-4256 on its downstream target genes HDAC5/p16^(INK4a) was studied in GC cells,and the underlying mechanisms were evaluated using dual luciferase reporter assay and Chromatin Immunoprecipitation(ChIP).Additionally,the role of the miR-4256/HDAC5/p16^(INK4a) axis in GC was studied using in vitro and in vivo experiments.Finally,the upstream regulators SMAD2/p300 that regulate miR-4256 expression and their role in GC were explored using in vitro experiments.miR-4256 was the most significantly upregulated miRNA and was overexpressed in GC cell lines and GC tissues;in vitro and in vivo results showed that miR-4256 promoted GC growth and progression.Mechanistically,miR-4256 enhanced HDAC5 expression by targeting the promoter of the HDAC5 gene in GC cells,and then restrained the expression of p16^(INK4a) through the epigenetic modulation of HDAC5 at the p16INK4a promoter.Furthermore,miR-4256 overexpression was positively regulated by the SMAD2/p300 complex in GC cells.Our data indicate that miR-4256 functions as an oncogene in GC via the SMAD2/miR-4256/HDAC5/p16^(INK4a) axis,which participates in GC progression and provides novel therapeutic and prognostic biomarkers for GC. 展开更多
关键词 Gastric cancer miR-4256 SMAD2 HDAC5 p16^(INK4a)
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Preparation and Study of Borosilicate Foam Glass with High Thermal Insulation and Mechanical Strength
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作者 Yiwen Zhang Jianjun Xie +6 位作者 Minghui Sun Shaolong Wang Tengfei Xu Yonggen Xu Xiaoqing Ding ying shi Lei Zhang 《Journal of Renewable Materials》 SCIE EI 2023年第5期2125-2141,共17页
Foam glass is a kind of green building material that is widely used because of its excellent thermal insulation and mechanical properties.In this study,the borosilicate foam glass was fabricated by powder sintering me... Foam glass is a kind of green building material that is widely used because of its excellent thermal insulation and mechanical properties.In this study,the borosilicate foam glass was fabricated by powder sintering method using recycled soda lime waste glass,quartz,and borax as the primary raw materials.CaCO_(3)was used as a foaming agent and Na_(2)CO_(3)as a flux agent.Results showed that as the quartz content decreases from 30 to 17.5 wt.%and borax content increases from 5 to 17.5 wt.%,the pore size,porosity,and thermal insulation of borosilicate foam glass increase significantly,while the compressive strength decreases slightly.When the content of quartz and borax are both 17.5 wt.%,borosilicate foam glass with outstanding performance can be prepared,whose pore distribution is uniform,mean pore size is 1.93 mm,total porosity is 83.44%,thermal conductivity is 0.0711W/(m⋅K),and compressive strength is 2.37 MPa.Finally,the influences of foaming agent content,flux agent content,foaming temperature,and holding time on the pore structure and various properties of borosilicate foam glass were investigated by orthogonal test.According to the results,the foaming temperature has a significant effect,and appropriate foaming agent content,flux agent content,and holding time help to form a uniform pore structure,thereby improving the thermal insulation and mechanical strength of the borosilicate foam glass. 展开更多
关键词 Foam glass waste glass thermal conductivity compressive strength
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Design of a rapid-cycling synchrotron for flash proton therapy
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作者 ying shi Man-Zhou Zhang +3 位作者 Lian-Hua Ou-Yang Zhi-Ling Chen Xiu-Fang Li De-Ming Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第10期1-11,共11页
The purpose of this study was to design a rapid-cycling synchrotron, making it capable of proton beam ultrahigh dose rate irradiation, inspired by laser accelerators. The design had to be cheap and simple. We consider... The purpose of this study was to design a rapid-cycling synchrotron, making it capable of proton beam ultrahigh dose rate irradiation, inspired by laser accelerators. The design had to be cheap and simple. We consider our design from six aspects: the lattice, injection, extraction, space charge effects, eddy current effects and energy switching. Efficiency and particle quantity must be addressed when injected. The space charge effects at the injection could affect particles' number. The eddy current effects in the vacuum chambers would affect the magnetic field itself and generate heat, all of which need to be taken into account. Fast extraction can obtain 10^(10) protons/pulse, equal to instantaneous dose rate up to 10~7 Gy/s in a very short time, while changing various extraction energies rapidly and easily to various deposition depths. In the further research, we expect to combine a delivery system with this accelerator to realize the FLASH irradiation. 展开更多
关键词 FLASH Rapid-cycling synchrotron Proton therapy
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Research on Operation Optimization of Heating System Based on Electric Storage Coupled Solar Energy and Air Source Heat Pump
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作者 Jingxiao Han Chuanzhao Zhang +5 位作者 LuWang ZengjunChang Qing Zhao ying shi JiaruiWu Xiangfei Kong 《Energy Engineering》 EI 2023年第9期1991-2011,共21页
For heating systems based on electricity storage coupled with solar energy and an air source heat pump(ECSA),choosing the appropriate combination of heat sources according to local conditions is the key to improving e... For heating systems based on electricity storage coupled with solar energy and an air source heat pump(ECSA),choosing the appropriate combination of heat sources according to local conditions is the key to improving economic efficiency.In this paper,four cities in three climatic regions in China were selected,namely Nanjing in the hot summer and cold winter region,Tianjin in the cold region,Shenyang and Harbin in the severe cold winter region.The levelized cost of heat(LCOH)was used as the economic evaluation index,and the energy consumption and emissions of different pollutants were analyzed.TRNSYS software was used to simulate and analyze the system performance.The Hooke-Jeeves optimization algorithm and GenOpt software were used to optimize the system parameters.The results showed that ECSA systemhad an excellent operation effect in cold region and hot summer and cold winter region.Compared with ECS system,the systemenergy consumption,and the emission of different pollutants of ECSA system can be reduced by a maximum of 1.37 times.In cold region,the initial investment in an air source heat pump is higher due to the lower ambient temperature,resulting in an increase in the LOCH value of ECSA system.After the LOCH value of ECSA system in each region was optimized,the heating cost of the system was reduced,but also resulted in an increase in energy consumption and the emission of different pollutant gases. 展开更多
关键词 Electric heat storage solar energy air source heat pump multi-objective optimization method LOCH
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基于非爆开采和固废资源化利用的硬岩矿山绿色开发(英文) 被引量:26
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作者 王少锋 孙立成 +4 位作者 黄麟淇 李夕兵 石英 姚金蕊 杜绍伦 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第9期1914-1928,共15页
基于深部高地应力、高地温、高井深等灾害因素的“变害为利”,提出深部固体资源开采技术变革思路,实现深部固体资源的绿色开采。首先,通过深部硬岩可截割性实验研究和回归分析,获得能够有效改善非爆机械化破岩的应力诱导调控方法。其次... 基于深部高地应力、高地温、高井深等灾害因素的“变害为利”,提出深部固体资源开采技术变革思路,实现深部固体资源的绿色开采。首先,通过深部硬岩可截割性实验研究和回归分析,获得能够有效改善非爆机械化破岩的应力诱导调控方法。其次,通过非爆机械化和智能化开采,实现以坚硬磷矿石为代表的深部硬岩连续化精准开采,确保贵州开阳磷矿资源的高回收率(大于90%)、低废(贫化率5%)、高效(开采效率107.7 t/h)开采。最后,开发矿山循环经济新模式,构建矿山全固废充填系统,实现矿山固废资源化利用。连续实施后,2018年开阳磷矿的磷石膏、黄磷渣、废石利用量分别达到1853.6×10^3 t/a、291.1×10^3 t/a和1493.8×10^3 t/a。 展开更多
关键词 硬岩矿山 非爆开采 固废充填 循环经济 固废资源化利用 绿色开采
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软件工程专业教学思考与实践 被引量:1
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作者 应时 李小红 +1 位作者 刘伟 李晓伟 《软件导刊》 2020年第1期15-17,共3页
围绕软件工程知识体系及其学习、构造、再造和应用等方面的特点,在建构主义学习理论的指导下,结合工程学科特点,讨论学好软件工程专业知识并铸造专业素质的价值观念,探讨突出和强化专业知识学习的教学方法,通过总结教学实践工作体会,提... 围绕软件工程知识体系及其学习、构造、再造和应用等方面的特点,在建构主义学习理论的指导下,结合工程学科特点,讨论学好软件工程专业知识并铸造专业素质的价值观念,探讨突出和强化专业知识学习的教学方法,通过总结教学实践工作体会,提出亟待解决的一系列教学问题。 展开更多
关键词 软件工程知识体系 建构主义学习理论 专业知识学习
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结晶高分子薄膜的内部和表面结构及光学性能 被引量:20
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作者 郑萃 姚雪容 +2 位作者 史颖 任毅 刘立志 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2018年第11期56-62,共7页
高分子薄膜的雾度贡献可分为表面雾度和内部雾度两部分。文中介绍了如何分离结晶高分子薄膜光学雾度的表面贡献和内部贡献,如何用白光干涉仪(轮廓仪)研究高分子薄膜表面的三维形态及表面粗糙度。相比于原子力显微镜而言,白光干涉轮廓仪... 高分子薄膜的雾度贡献可分为表面雾度和内部雾度两部分。文中介绍了如何分离结晶高分子薄膜光学雾度的表面贡献和内部贡献,如何用白光干涉仪(轮廓仪)研究高分子薄膜表面的三维形态及表面粗糙度。相比于原子力显微镜而言,白光干涉轮廓仪可快速获得面积大很多倍的表面三维形态及统计性更好的表面粗糙度。并在此基础上进一步介绍了如何定量地研究高分子薄膜的表面粗糙度与表面雾度之间的关系。研究表明,尽管所研究的薄膜材料不同,制造工艺也不同,薄膜的厚度也有不相同,但由白光干涉仪得到的薄膜的表面粗糙度与表面雾度之间呈较好的线性正相关。而且,相对于内部雾度,薄膜的表面雾度对总雾度的贡献更大。此外还介绍了用激光散射研究高分子薄膜中较小球晶结构的方法,实验结果表明,用偏光显微镜研究这类尺寸较小的球晶是很困难的。对于结晶度相同的薄膜样品,其内部雾度可以差别很大。在结晶度相近的情况下,有无球晶形成,球晶形态的完善程度及大小是调节内部雾度的主要因素。球晶尺寸越大结构越完善,内部雾度也越大。 展开更多
关键词 聚乙烯薄膜 表面粗糙度 球晶 雾度
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异氰酸酯硬段对聚氨酯结构及性能的影响 被引量:11
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作者 刘长伟 史颖 +4 位作者 马驰 刘立志 刘紫婷 却毓晖 王连慧 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2021年第3期79-84,共6页
异氰酸酯的种类和含量对所合成的聚氨酯性能有重要的影响。文中以聚四氢呋喃醚二醇(PTMG)为软段,甲苯二异氰酸酯(TDI)、二苯基甲烷二异氰酸酯(MDI)和六亚甲基二异氰酸酯(HDI)分别为硬段,采用预聚体法合成了一系列具有不同硬段及软硬段... 异氰酸酯的种类和含量对所合成的聚氨酯性能有重要的影响。文中以聚四氢呋喃醚二醇(PTMG)为软段,甲苯二异氰酸酯(TDI)、二苯基甲烷二异氰酸酯(MDI)和六亚甲基二异氰酸酯(HDI)分别为硬段,采用预聚体法合成了一系列具有不同硬段及软硬段比例的聚氨酯,并通过红外光谱、小角X射线散射、动态力学热分析及热重分析等方法,研究了异氰酸酯种类及比例对聚氨酯软硬段相分离结构和性能的影响。结果表明,由柔性脂肪族异氰酸酯所合成的聚氨酯其相分离程度更大,软段和硬段所对应的玻璃化转变温度差异更大。由链段刚性较强的TDI所合成的聚氨酯相分离程度更小,软硬段的玻璃化转变温度相差不大,更适合用于阻尼吸音的聚氨酯材料。同时,提高异氰酸酯指数使硬段含量增加,链段运动更加困难,相分离程度有所降低,会使材料的力学性能有所提升,但是耐热性降低。 展开更多
关键词 聚氨酯 异氰酸酯 相分离 小角散射
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一种基于日志聚类的多类型故障预测方法 被引量:7
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作者 王卫华 应时 +2 位作者 贾向阳 王冰明 程国力 《计算机工程》 CAS CSCD 北大核心 2018年第7期67-73,共7页
现有故障预测方法的日志事件多数是无规律交错存在的,且不同类型的故障事件所涉及的事件数量与时间范围存在一定差异。为在故障预测时能够提供故障相关信息,提出一种基于频繁日志事件序列对多种不同类型的故障进行预测的方法。以日志事... 现有故障预测方法的日志事件多数是无规律交错存在的,且不同类型的故障事件所涉及的事件数量与时间范围存在一定差异。为在故障预测时能够提供故障相关信息,提出一种基于频繁日志事件序列对多种不同类型的故障进行预测的方法。以日志事件序列之间的最长公共子序列作为其相似性度量,使用聚合层次聚类算法挖掘与故障事件相关的频繁事件序列。在频繁事件序列的基础上生成故障事件预测规则,并给出一种对故障事件预测规则进行过滤的方法,将过滤后的规则应用到测试集上进行故障预测。实验结果表明,该方法不仅能够进行有效的故障预测,而且可以平衡故障预测的准确率和召回率。 展开更多
关键词 故障事件预测 频繁事件序列 规则过滤 聚合层次聚类算法 超级计算机
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元数据驱动的多样化服务的混合编排方法 被引量:3
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作者 张光宇 应时 +1 位作者 贾向阳 骆慧 《计算机应用研究》 CSCD 北大核心 2018年第3期777-781,共5页
服务协议的多样性带来了消息结构的多样性,而BPEL不支持多样化的服务消息结构,因此在多样化的服务组合方面存在服务交互不匹配的问题。为此,提出元数据驱动的多样化服务的混合编排方法,对多样化服务进行元数据建模,描述服务消息结构,服... 服务协议的多样性带来了消息结构的多样性,而BPEL不支持多样化的服务消息结构,因此在多样化的服务组合方面存在服务交互不匹配的问题。为此,提出元数据驱动的多样化服务的混合编排方法,对多样化服务进行元数据建模,描述服务消息结构,服务适配器利用元数据转换多样化的服务消息,在统一的消息结构上定义流程中服务间的数据交互,总体结合了基于元数据的数据依赖定义和BPMN定义完整地描述一个流程。通过案例测试以及可用性评估,结果验证了方法的可行性。该方法在一定程度上解决了多样化服务编排的问题,对多样化的服务协议类型可扩展。 展开更多
关键词 服务组合 流程编排 服务协议 元数据
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应用软件运行日志的收集与服务处理框架 被引量:14
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作者 张骁 应时 张韬 《计算机工程与应用》 CSCD 北大核心 2018年第10期81-89,142,共10页
随着现代计算机系统的规模和复杂性不断增大,其运行日志的数量也不断增多,但是由于日志数据的规模巨大、内容杂乱,用户查看日志数据具有一定的困难,因此对应用软件运行日志进行有效收集与处理具有重要意义。提出了一种应用软件运行日志... 随着现代计算机系统的规模和复杂性不断增大,其运行日志的数量也不断增多,但是由于日志数据的规模巨大、内容杂乱,用户查看日志数据具有一定的困难,因此对应用软件运行日志进行有效收集与处理具有重要意义。提出了一种应用软件运行日志的收集与服务处理框架,利用分布式收集策略对日志数据收集,定义了一种多层次数据存储结构对日志数据进行存储,并向用户提供日志数据查询服务。通过对某综合减灾系统的日志数据分析验证了提出的日志数据收集与服务处理框架的实用性,并与传统的日志收集分析软件ELK和Chukwa进行了对比。 展开更多
关键词 日志数据 框架 收集处理 分布式收集 多层次数据存储 查询服务
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一种支持设计时软件重用的反射式软件体系结构及其形式化研究 被引量:3
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作者 罗巨波 应时 刘天时 《计算机工程与科学》 CSCD 北大核心 2019年第8期1434-1443,共10页
软件体系结构在软件重用中有着特殊的意义。缺乏显式的描述并使用支持体系结构重用过程的信息和缺乏有效的重用方法是软件体系结构难以重用最根本的原因。在软件设计阶段,将元信息、元建模、反射和软件体系结构结合起来,构造了一种支持... 软件体系结构在软件重用中有着特殊的意义。缺乏显式的描述并使用支持体系结构重用过程的信息和缺乏有效的重用方法是软件体系结构难以重用最根本的原因。在软件设计阶段,将元信息、元建模、反射和软件体系结构结合起来,构造了一种支持软件体系结构重用的反射式软件体系结构。给出了基于反射式软件体系结构的软件体系结构重用过程。给出了反射式软件体系结构的具体化过程的基本原理和具体化操作的Object-Z形式化描述,即创建元组件、创建元连接器、创建元组合件操作的形式化描述。给出了基于反射式软件体系结构的软件体系结构重用的支撑工具的设计过程。 展开更多
关键词 软件体系结构重用 反射式软件体系结构 具体化 Object-Z形式化描述
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基于细观试验和离散元法的盐岩力学特性 被引量:2
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作者 胡唯哲 谢凌志 +3 位作者 岑望来 殷实 罗云川 赵鹏 《岩土力学》 EI CAS CSCD 北大核心 2018年第6期2073-2081,共9页
当前盐岩的宏观力学模型通常是唯象模型,不能很好地解释盐岩受力变形破坏的真正物理基础。盐岩是由于化学沉积而形成的矿物集合体,是一种主要由NaCl和少量杂质组成的多晶体,其变形机制主要由晶粒与晶界的力学特性控制。通过扫描电镜(SE... 当前盐岩的宏观力学模型通常是唯象模型,不能很好地解释盐岩受力变形破坏的真正物理基础。盐岩是由于化学沉积而形成的矿物集合体,是一种主要由NaCl和少量杂质组成的多晶体,其变形机制主要由晶粒与晶界的力学特性控制。通过扫描电镜(SEM),获得盐岩晶粒的微细观结构特征,采用分子动力学方法和纳米压痕技术,确定盐岩晶粒和晶界的微细观力学参数;将盐岩晶粒作为块体,基于Voronoi多边形技术,建立盐岩的微细观数值模型;利用离散元方法,对盐岩试件在单轴压缩和直剪条件下的宏观力学行为进行了数值模拟。数值模拟结果与宏观力学试验结果吻合度高,表明基于盐岩微细观晶粒结构特征并结合离散元数值模拟的方法能够较好地研究盐岩的宏观力学性能及其材料物理基础。 展开更多
关键词 盐岩 离散元法 分子动力学 微细观模型
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Choice for graphene as conductive additive for cathode of lithium-ion batteries 被引量:11
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作者 ying shi Lei Wen +2 位作者 Songfeng Pei Minjie Wu Feng Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第3期19-26,共8页
Graphene is a promising conductive additive for the lithium-ion batteries(LIBs) and shows great potential especially with its fast development of the large scale fabrication technology. This work has explored the infl... Graphene is a promising conductive additive for the lithium-ion batteries(LIBs) and shows great potential especially with its fast development of the large scale fabrication technology. This work has explored the influence of the incorporation of graphenes prepared by three typical methods on the electrochemical performance of the LiCoO_2-based cathode focusing on the choice for the effective graphene as conductive additive for the cathode of LIBs. Through the comparison of the intrinsic characteristics of graphenes and the electrochemical performance of electrodes with graphene, it is found that graphene with low disorder degree and large size is not suitable for LiCoO_2 cathodes as conductive additive. Conversely, the graphene with oxygen functional groups, relatively low surface area and proper size displays much better electrochemical performance when it is used as conductive additive. This work also demonstrates the transmission mechanism for different graphenes as conductive additives in the LiCoO_2 materials, and further reveals that the conductivity of graphene is not the only factor as conductive additives, surface chemistry and sheet size of the graphene are also essential factors which greatly influence the electrochemical performance of electrode. In addition, when combined with Super P, only 1% graphene is enough to construct an efficient conductive network in the electrode. This study also gives a new sight on the practical application of graphene as conductive additive for high performance LIBs. 展开更多
关键词 GRAPHENE CONDUCTIVE additive LITHIUM-ION batteries LICOO2 CATHODE
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