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Secondary trading of airport slots:Issues and challenges

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Chinese Journal of Aeronautics 2023年第12期36卷 1-12页

作者： Yanjun WANg Mengyin WANg Weishan XU Mark hansen College of Civil Aviation Nanjing University of Aeronautics and AstronauticsNanjing 210016China Adam Smith Businesses School University of GlasgowGlasgow G128QQUK Department of Civil and Environmental Engineering University of CaliforniaBerkeley 94720USA

Most Level 3 airports around the world suffer severe congestion and flight *** have to obtain airport slots in order to schedule flights at such *** main way for airlines to acquire slots is primary slot allocation,in which a slot coordinator distributes slots to airlines according to certain rules and *** to excessive demand for slots and restrictions on allocation rules,it is difficult for some airlines to obtain the desired slots in this *** way for airlines to obtain slots is through secondary slot trading,in which slots can be redistributed among airlines without being returned to slot *** secondary trading of airport slots has played a positive role in promoting the efficient utilization of slot resources,but systematic studies are *** paper discusses the reasons for the existence of slot secondary trading,sorts out the main policies and rules governing the mechanism,investigates its impacts on the industry and society,and points out the major problems and *** paper provides a reference for subsequent research and practical application of airport slot secondary trading in the future.

关键词： Air traffic management Airport capacity Airport slot allocation Market-based mechanism Secondary slot trading

中深层地热能同轴套管换热器储能发电系统热力学性能分析

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西安交通大学学报 2024年第1期58卷 126-137页

作者：令兰宁姚尔人孙昊李瑞雄邹瀚森王焕然席光张孙孝西安交通大学能源与动力工程学院西安710049 长安大学建筑工程学院西安710061

针对地热能发电技术效率低、稳定性差的问题,提出一种兼具同轴套管取热技术和压缩空气储能技术特点的中深层地热能同轴套管换热器储能发电系统,通过建立系统的热力学模型,研究了典型工况下系统关键参数和热力学性能的演化规律,揭示了不... 详细信息

针对地热能发电技术效率低、稳定性差的问题,提出一种兼具同轴套管取热技术和压缩空气储能技术特点的中深层地热能同轴套管换热器储能发电系统,通过建立系统的热力学模型,研究了典型工况下系统关键参数和热力学性能的演化规律,揭示了不同运行特征下地热恢复与提取的动态机制。研究结果表明:储能发电系统的运行分为非稳定循环和稳定循环阶段,在非稳定循环阶段中,热提取量和膨胀机输出功随循环次数的增加而增加,而热补偿量和系统效率呈相反趋势变化;当热提取量、热补偿量和地热消耗量达到平衡时,储能发电系统从第8次循环进入稳定循环阶段,稳定循环中各参数不随循环次数改变,单次循环输出电量为47 956.7 kW·h,系统效率达到63.5%;通过提升压缩机压比和补热水流量可以提升地热恢复温度:当压缩机压比由6提升至7时,深度为1 300 m、半径为0.116 m处,岩土温度多提升4.3℃,当补热水流量由4.5 m^(3)/h提升至6 m^(3)/h,同一处岩土温度多提升6.4℃,该研究为提高地热能发电效率和稳定性提供了新方案。

关键词：地热发电稳定性地热恢复热力学性能

Epidemiologic methods for investigating male fecundity

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Asian Journal of Andrology 2014年第1期16卷 17-22页

作者： Jrn Olsen Cecilia Host Ramlau-hansen Department of Public Health Section for Epidemiology Aarhus University Aarhus Denmark

Fertility is a couple concept that has been measured since the beginning of demography, and male fecundity （his biological capacity to reproduce） is a component of the fertility rate. Unfortunately, we have no way of measuring the male component directly, although several indirect markers can be used. Population registers can be used to monitor the proportion of childless couples, couples who receive donor semen, trends in dizygotic twinning, and infertility diagnoses. Studies using time-to-pregnancy （TTP） may identify couple subfecundity, and TTP data will correlate with sperm quality and quantity as well as sexual activity and a number of other conditions. Having exposure data available for couples with a fecund female partner would make TTP studies of interest in identifying exposures that may affect male fecundity. Biological indicators such as sperm quality and quantity isolate the male component of fertility, and semen data therefore remain an important source of information for research. Unfortunately, often over half of those invited to provide a sperm sample will refuse, and the study is then subject to a selection that may introduce bias. Because the most important time windows for exposures that impair semen production could be early fetal life, puberty, and the time of ejaculation; longitudinal data over decades of time are required. The ongoing monitoring of semen quality and quantity should continue, and surveys monitoring fertility and waiting TTP should also be designed.

关键词： data collection epidemiology epidemiological monitoring fertility sperm count time-to-pregnancy (TTP)

文旅融合背景下历史街区社会韧性测度与业居关联微干预调节——以重庆市磁器口街区为例

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现代城市研究 2024年第9期39卷 66-73页

作者：肖竞钟海洁邵筱萱谢汉森曹珂重庆大学建筑城规学院山地城镇建设与新技术教育部重点实验室自然资源部国土空间规划监测评估预警重点实验室重庆大学建筑城规学院宾夕法尼亚大学重庆工商大学公共管理学院

文章以文旅融合发展背景下历史街区经济韧性与社会韧性平衡保持为目标,提出“业居关联”的历史街区社会韧性议题研究思路,建构出以态征测度、回归分析、阈值计算为分析步骤,以居民保有率、邻里网络密度、环境滋扰指数和商铺比例、房租... 详细信息

文章以文旅融合发展背景下历史街区经济韧性与社会韧性平衡保持为目标,提出“业居关联”的历史街区社会韧性议题研究思路,建构出以态征测度、回归分析、阈值计算为分析步骤,以居民保有率、邻里网络密度、环境滋扰指数和商铺比例、房租价格、访客载荷为表征指标因子的历史街区业居态征定量测度与关联分析方法;以重庆市磁器口历史街区的多期多区多态数据为研究样本,揭示出文旅商业化进程中历史街区社会韧性的3项衰减机理:空间竞价导致本地居民外迁、业态置换导致邻里阻隔、访客超载导致生活滋扰,以及相应业居作用关系下街区社会韧性保持的业居指标阈值。上述方法与指标结论遵循历史街区业居态征交互影响、动态变化的现实逻辑,突破了历史街区韧性研究“评调脱节”的技术瓶颈,有助于将定量评测结论转化为定量调控措施,可为我国历史街区社会韧性研究和文旅融合发展实践提供有益参考。

关键词：存量更新历史街区文旅融合社会韧性业居关联微干预调节磁器口历史街区

Therapeutic procedures for submucosal tumors in the gastrointestinal tract

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World Journal of gastroenterology 2007年第24期13卷 3316-3322页

作者： Laura graves Ponsaing Mark Berner hansen Department of Surgical gastroenterology K Bispebjerg University Hospital of Copenhagen Denmark

This review is part three of three and will present an update on the therapeutic options and procedures concerning gastrointestinal (gI) submucosal tumors (SMTs). The aim of this paper is to investigate the treatments of gI SMTs and to present a case of a gastrointestinal stromal tumor (gIST). Literature searches were performed to find information on therapy for gI SMTs. Based on these searches, the optimal therapeutic procedures could be outlined. The choice of treatment of localized tumors is endoscopic resection if possible or, alternatively, laparoscopic resection or surgical resection by an open procedure. However, benign SMTs should only be excised if symptoms are present, and gISTs should be treated with particular precautions. Irresectable or recurrent gISTs may be successfully treated with the tyrosine kinase inhibitor, imatinib.

关键词： Submucosal tumor Treatment Case story Endoscopic mucosal resection Imatinib

Impact of the gut microbiota on rodent models of human disease

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World Journal of gastroenterology 2014年第47期20卷 17727-17736页

作者： Axel Kornerup hansen Camilla Hartmann Friis hansen Lukasz Krych Dennis Sandris Nielsen Section of Experimental Animal Models Department of Veterinary Disease BiologyUniversity of Copenhagen1871 FrederiksbergDenmark Department of Food Science Faculty of SciencesUniversity of Copenhagen1958 FrederiksbergDenmark

Traditionally bacteria have been considered as either pathogens, commensals or symbionts. The mammal gut harbors 1014 organisms dispersed on approximately 1000 different species. Today, diagnostics, in contrast to previous cultivation techniques, allow the identification of close to 100% of bacterial species. This has revealed that a range of animal models within different research areas, such as diabetes, obesity, cancer, allergy, behavior and colitis, are affected by their gut microbiota. Correlation studies may for some diseases show correlation between gut microbiota composition and disease parameters higher than 70%. Some disease phenotypes may be transferred when recolonizing germ free mice. The mechanistic aspects are not clear, but some examples on how gut bacteria stimulate receptors, metabolism, and immune responses are discussed. A more deeper understanding of the impact of microbiota has its origin in the overall composition of the microbiota and in some newly recognized species, such as Akkermansia muciniphila, Segmented filamentous bacteria and Faecalibacterium prausnitzii, which seem to have an impact on more or less severe disease in specific models. Thus, the impact of the microbiota on animal models is of a magnitude that cannot be ignored in future research. Therefore, either models with specific microbiota must be developed, or the microbiota must be characterized in individual studies and incorporated into data evaluation.

关键词： Animal models gut microbiota Diabetes Obesity Cancer Allergy Behavior Colitis

On the Existence of Robot Zombies and our Ethical Obligations to AI Systems

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Journal of Social Computing 2023年第4期4卷 270-274页

作者： Luke R.hansen the Computer Science Department Stanford UniversityStanfordCA 94305USA

As artificial intelligence algorithms improve,we will interact with programs that seem increasingly *** may never know if these algorithms are sentient,yet this quality is crucial to ethical considerations regarding their moral *** will likely have to make important decisions without a full understanding of the relevant issues and *** this ignorance,we ought to take seriously the prospect that some systems are *** would be a moral catastrophe if we were to treat them as if they were not sentient,but,in reality they are.

关键词： artificial intelligence sentience ethics

Dietary fats may impact semen quantity and quality

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Asian Journal of Andrology 2012年第4期14卷 511-512页

作者： Jorn Olsen Cecilia Host Ramlau-hansen Department of Public Health Section of Epidemiology Aarhus University 8000 Aarhus C Denmark

This recently published cross-sectional study that included 99 men from Massachusetts general Hospital Fertility Center, Boston, MA, USA, reports that a high intake of saturated fats was inversely associated with sperm concentration and total sperm count and a high intake of omega-3 polyunsaturated fats （PUFAs） was positively associated with sperm morphology. Although the study is based upon a highly selected group of males and is of cross-sectional nature, the findings are of interest, since poor semen quality is a frequent problem in some parts of the world and identification of modifiable risk factors is highly wanted.

关键词： MEN

空间变异性蠕变地层中综合管廊变形安全可靠度预测

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武汉大学学报（工学版） 2024年第3期57卷 302-310页

作者：沈才华王业钊蒋新宇蔡丹丹于瀚森河海大学土木与交通学院江苏南京210098 宜兴市工程建设施工图审查中心江苏宜兴214200 宿迁市高速铁路建设发展有限公司江苏宿迁223800

针对宿迁软土层空间变异性进行统计分析,获得沿综合管廊轴向软土层底高程截断式正态分布函数。考虑软土层底高程空间变异性和蠕变参数不均匀性,引入蒙特卡洛法,建立了综合管廊运营期安全预测随机有限元模拟方法,分析了支护结构对综合管... 详细信息

针对宿迁软土层空间变异性进行统计分析,获得沿综合管廊轴向软土层底高程截断式正态分布函数。考虑软土层底高程空间变异性和蠕变参数不均匀性,引入蒙特卡洛法,建立了综合管廊运营期安全预测随机有限元模拟方法,分析了支护结构对综合管廊安全性的影响规律。结合综合管廊结构的允许拉应力设计指标,提出了综合管廊运营期变形安全可靠度设计方法,分析了不同综合管廊宽度对管廊安全性的影响规律。结果表明:软土层空间变异性对综合管廊运营期最大等效应力影响较大;支护结构可大幅增加综合管廊安全性,保留支护结构工况下综合管廊最大拉应力可靠度0.9控制值(可靠概率为0.9时对应的控制值)1.004 1 MPa比拆除支护结构的1.582 2 MPa减小36.53%,综合管廊最大差异沉降可靠度0.9控制值2.39 mm比拆除支护结构工况的7.45 mm减小67.92%;综合管廊宽度对管廊最大拉应力有影响,宽度越大,管廊最大拉应力累计概率曲线越平缓,风险越大。

关键词：综合管廊可靠度随机有限元蠕变软土空间变异性