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Evaluation of freezing state of sandstone using ultrasonic time-frequency characteristics

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第3期15卷 584-599页

作者： Jiwei Zhang Julian Murton Tim cane Vikram Maji Lili Sui Shujie Liu Song Zhang University of Science and Technology Beijing Beijing100083China permafrost Laboratory Department of GeographyUniversity of SussexBrightonBN19QJUK Beijing Key Laboratory of Urban Underground Space Engineering University of Science and Technology BeijingBeijing100083China Department of Earth Sciences Indian Institute of Technology KanpurKanpurIndia North China University of Technology Beijing100041China

Common problems in engineering projects that involve artificial ground freezing of soil or rock include inadequate thickness,strength and continuity of artificial frozen *** is difficult to evaluate the freezing state using only a few thermometer holes at fixed positions or with other existing *** we report a novel experimental design that investigates changes in ultrasonic properties(received waveform,wave velocity V_(p),wave amplitude,frequency spectrum,centroid frequency f_(c),kurtosis of the frequency spectrum KFS,and quality factor Q)measured during upward freezing,compared with those during uniform freezing,in order to determine the freezing state in 150 mm cubic blocks of Ardingly *** content,porosity and density were estimated during upward freezing to ascertain water migration and changes of porosity and density at different *** period of receiving the wave increased substantially and coda waves changed from loose to compact during both upward and uniform *** trend of increasing V_(p) can be divided into three stages during uniform *** upward freezing,V_(p) increased more or less *** frequency spectrum could be used as a convenient and rapid method to identify different freezing states of sandstone(unfrozen,upward frozen,and uniformly frozen).The continuous changes in reflection coefficient r_(φ),refraction coefficient t_(φ) and acoustic impedance field are the major reason for larger reflection and refraction during upward freezing compared with uniform *** velocity V_(p),wave amplitude A_(h),centroid frequency f_(c) and quality factor Q were adopted as ultrasonic parameters to evaluate quantitatively the temperature T of uniformly frozen sandstone,and their application within a radar chart is *** of V_(p) provides a convenient method to evaluate the freezing state and calculate the cryofront height and frozen section thickness of upward frozen sandstone,with

关键词： Frozen sandstone Uniform freezing Upward freezing Ultrasonic testing Freezing state

Impairment of non-muscle myosin IIA in human CD41 T cells contributes to functional deficits in the elderly

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Cellular & Molecular Immunology 2012年第1期9卷 86-96页

作者： Stefania cane Subramaniam ponnappan Usha ponnappan Department of Microbiology and Immunology University of Arkansas for Medical SciencesLittle RockARUSA Department of Geriatrics University of Arkansas for Medical SciencesLittle RockARUSA

physiological aging imposes significant alterations in the repertoire of T cells and all associated *** several studies have reported defects upon antigen-induced activation of T cells during aging,the molecular mechanisms that control T-cell receptor(TCR)downmodulation remain to be fully *** previous studies have assessed the role of F-actin in regulating activation-induced TCR internalization,few have delineated the roles of motor proteins,such as non-muscle myosin IIA(NMMIIA).In this study,we describe a series of experiments supporting the hypothesis that effective TCR downmodulation requires not only efficient reorganization of the actin cytoskeleton,but also functional *** the first time,we show that CD41 T cells from elderly human donors have dysfunctional NMMIIA that contributes to delaying activation-induced TCR internalization and impairing calcium ***,our results demonstrate that chemical inhibition of NMMIIA in CD41 T cells from young donors also results in complete abrogation of TCR internalization,strongly supporting the fundamental role of NMMIIA in modulating this *** observations that the generation of an efficient T-cell response requires migration prompted us to investigate whether NMMIIA also plays a regulatory role in CD41 T-cell *** show that chemical inhibition of NMMIIA downmodulates chemotactic migration in CD41 T cells from both young and elderly ***,these data demonstrate a significant contribution of dysfunctional NMMIIA to TCR-mediated functional defects during aging.

关键词： chemotaxis Hsp90 immune senescence NMMIIA TCR internalization

基于DAB-IBDC控制器的储能系统控制研究

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基于DAB-IBDC控制器的储能系统控制研究

作者： Makuwatsine Munashe cane（慕那）济南大学

学位级别：硕士

本硕士论文的研究重点是对隔离双向全桥直流-直流变换器的控制策略进行分析和优化。通过设计、开发和测试各种控制策略,旨在提高这些变换器的性能和效率。论文包括五个章节,每个章节都涉及问题的特定方面。第一介绍了双有源桥隔离双向直... 详细信息

本硕士论文的研究重点是对隔离双向全桥直流-直流变换器的控制策略进行分析和优化。通过设计、开发和测试各种控制策略,旨在提高这些变换器的性能和效率。论文包括五个章节,每个章节都涉及问题的特定方面。第一介绍了双有源桥隔离双向直流-直流变换器作为电力电子的关键组件,实现两个具有电气隔离的直流电源之间的能量传输。强调了控制在实现最佳性能、效率和系统稳定性方面的重要性。变换器的复杂行为和非线性特性使得设计高效控制策略具有挑战性。因此,本研究重点探索和开发基于双有源桥隔离双向直流-直流变换器的能量存储系统的先进控制技术。第二深入分析了单相移(SpS)控制原理。它考察了每个阶段开关和二极管的开启和关闭状态,并建立了电感电流、传输功率、回流功率和电感电流峰值的数学表达式。分析了这些变量与相移之间的关系,表明尽管可以减少回流功率,但无法完全消除。将电压匹配值k接近1会降低回流功率、电感电流峰值、变换器损耗,并提高传输效率。理论分析经过仿真验证。第三着重研究双相移(DpS)控制。它分析了开关状态,推导了每个阶段变压器的电感电流、主次侧电压的表达式。得到了传输功率和回流功率的数学表达式。本章探讨了基于单闭环和子段最小回流功率的最小回流功率控制方法。仿真验证证明这两种方法在减少回流功率和稳定输出电压方面都有效。与DpS控制相比,单闭环方法具有更小的电感电流峰值和更高的系统传输能量效率。第四研究了三相移(TpS)控制。分析了将一个周期分为八个阶段的原理,考虑了每个阶段开关管的导通、关断、电流大小和方向。在稳态条件下建立了传输功率、输出电流和回流功率的数学模型。基于数学模型推导了回流功率的优化策第五介绍了隔离双向全桥直流-直流变换器的实验原理和原型构建。讨论了参数指标、开关器件的选择以及高频变压器的设计。提供了对主电路、驱动电路和相关子电路的详细描述,包括隔离、电源和驱动子电路的设计。编写了带有死区的相移程序,并对实验原型进行了初步测试。逐步调试了控制电路、驱动电路和主电路,并提供了实验波形。经过整合和测试的原型实现了2.8 k W的输出功率。在三种控制模式下的实验波形验证了理论分析的准确性。总的来说,通过对隔离双向全桥直流-直流变换器的控制策略进行分析和优化,本研究对于推进电力电子技术的发展和更高效可靠的能量存储系统的开发具有重要贡献。

关键词： DAB IBDC SpS DpS TpS 控制策

Weed Classification Using particle Swarm Optimization and Deep Learning Models

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Computer Systems Science & Engineering 2023年第1期44卷 913-927页

作者： M.Manikandakumar p.Karthikeyan Department of Computer Science and Engineering Thiagarajar College of EngineeringTamil NaduIndia Department of Information Technology Thiagarajar College of EngineeringTamil NaduIndia

Weed is a plant that grows along with nearly allfield crops,including rice,wheat,cotton,millets and sugar cane,affecting crop yield and *** and accurate identification of all types of weeds is a challenging task for farmers in earlier stage of crop growth because of *** address this issue,an efficient weed classification model is proposed with the Deep Convolutional Neural Network(CNN)that implements automatic feature extraction and performs complex feature learning for image *** this work,weed images were trained using the proposed CNN model with evolutionary computing approach to classify the weeds based on the two publicly available weed *** Tamil Nadu Agricultural University(TNAU)dataset used as afirst dataset that consists of 40 classes of weed images and the other dataset is from Indian Council of Agriculture Research–Directorate of Weed Research(ICAR-DWR)which contains 50 classes of weed *** effective particle Swarm Optimization(pSO)technique is applied in the proposed CNN to automa-tically evolve and improve its classification *** proposed model was evaluated and compared with pre-trained transfer learning models such as GoogLeNet,AlexNet,Residual neural Network(ResNet)and Visual Geometry Group Network(VGGNet)for weed *** work shows that the performance of the pSO assisted proposed CNN model is significantly improved the success rate by 98.58%for TNAU and 97.79%for ICAR-DWR weed datasets.

关键词： Deep learning convolutional neural network weed classification transfer learning particle swarm optimization evolutionary computing Algorithm 1:Metrics Evaluation

The Sports-Recreational Animation as a Factor for Tourism Development

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Journal of Tourism and Hospitality Management 2014年第1期2卷 1-5页

作者： Zlatko Jakovlev cane Koteski Snezana Bardarova Mimoza Serafimova Kristijan Dzambazoski University Goce Delcev Stip Republic of Macedonia Agency for Tourism promotion of Republic of Macedonia Skopje Republic of Macedonia

Sports and tourism activities act together. So today, sports tourism is undoubtedly one of the most important industries characterized by ever increasing profits, almost without experiencing any shocks and repercussions of the global economic crisis. Tourist agencies, touristic facilities, and touristic places are trying in every way to animate tourists with some sports. Sport is fun for everyone. Modern hotels have pools, golf courses, playgrounds, gyms, etc., in order for tourists to do sports and to have fun. On the other side, tourist agencies organize visits to some (important) sports events for visitors to ride and to have fun. Hence, the objective of the sport is to animate the tourists. For example, the Olympic Games is a world most famous sports event where a lot of money is spent in order for visitors, who came for that event only to enjoy from all over the world, to have fun. Apparently, there is a link between sport and animation in tourism, and it is necessary to make investments in sport if we want to put more fun in tourism. Although tourism is not a sport branch, it covers many sporting activities (sports recreation, sports events, etc.). It can be concluded that tourism and sport are interrelated phenomena.

关键词：旅游业旅游经济旅游市场旅游景点服务业酒店管理

RECONSTRUCTION OF WIND STRESS ANOMALIES SIMULATED BY AN AGCM USING SVD TECHNIQUE

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Acta meteorologica Sinica 1996年第3期10卷 257-269页

作者：倪允琪 S.E.Zebiak M.A.cane L.Marx Department of Atmospheric Sciences Nanjing University.Nanjing 210093 Lamont-Doherty Earth Observatory of Columbia University.palisades NY 10964USA Center for Ocean-Land-Atmosphere Studies.Calverton MD 20705-3106USA

Systematic errors in the COLA R15 AGCM are analyzed by the SVD *** order to remove or reduce this kind of error source and reduce climate drift in coupled runs a way in which the wind stress anomalies simulated by an AGCM are reconstructed is proposed by using SVD anal- *** results show that not only wind stress anomalies simulated by an AGCM are obviously improved by reconstructed wind stress anomalies but also this reconstruction has a func- tion of a low-pass time filter,as a result,response of the ZC ocean model to reconstructed wind stress anomalies is more realistic than that of simulated wind stress anomalies by an *** this paper,application of the hybrid couple ocean-atmosphere model is further discussed.

关键词： reconstruction wind stress anomaly SVD technique climate signal climate change

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Animator＇s Roles in Enriching the Content of Tourist Stay

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Journal of Tourism and Hospitality Management 2014年第3期2卷 133-139页

作者： Zlatko Jakovlev cane Koteski Snezana Bardarova Aleksandra Zezova Kristijan Dzambazoski Gorancho Koteski University Goce Deicer Stip Republic of Macedonia Agency for Tourism promotion of Republic of Macedonia Skopje Republic of Macedonia Army of Republic of Macedonia Skopje Republic of Macedonia

For successful animation of visitors, animators must perform very complex, demanding, and dynamic tasks. professional performance of tasks implies the need for an animator to be a complete person. This means that he/she not only must have a sound education, but also have to be specialized for certain activities. There are different types of animators so that their diversity mirrors the success of the hotel. Animators must have certain basic physical and psychological characteristics. So, despite the knowledge and experience, animators must have inherent characteristics such as talent, humour, to be friendliness, and so on. Sense of humour and ability to work with people are two important characteristics of a successful animator. Many hotels need animators who can entertain tourists and make their stay memorable resort experience, which will be a reason for return of tourists. One of the key factors for tourism success is animator. Today, the whole tourism sector is based on animation of the tourists. The purpose of this paper is to show the role of the animator in enriching the content of tourist stay. To successfully execute the animation to the tourists, animators must meet certain characteristics which will be analysed in this paper. In this research will be used methods of analysis of scientific literature on the impact of animation on enrichment of tourist stay. The research stems from the fact that animation is one of the most important animation-motivational factors for the development of tourism.

关键词：旅游业旅游经济旅游市场旅游景点服务业酒店管理

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流水账的十六个关键词

中学生百科（阅读写作） 2004年第4期 16-17页

作者： cane

[选择]高二开学,我选择理科。[后来]小小一本正经地摇头。石头抛来无数个怜悯眼神。多多跳起来骂我脑袋秀逗了。阿凯在长途电话里毫不留情地喝倒彩。我皱皱眉,还是义无反顾地在志愿单上写了“选理”。然后Wine来信了,她的评价是: “哎,... 详细信息

[选择]高二开学,我选择理科。[后来]小小一本正经地摇头。石头抛来无数个怜悯眼神。多多跳起来骂我脑袋秀逗了。阿凯在长途电话里毫不留情地喝倒彩。我皱皱眉,还是义无反顾地在志愿单上写了“选理”。然后Wine来信了,她的评价是: “哎,你这别扭的小孩。”我知道她想说的还有很多,比如“其实你真的很不适合”。[数学]我承认自己是太冒险了,这份冒险却让我情不自禁地觉得我伟大。我的文科很好,这么多年我一直是个彻头彻尾的偏科生,最惨不忍睹的一门考试永远是数学。

关键词：流水账关键词石头节奏数学长途电话垃圾桶理科叶子文科

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厄尔尼诺-南方涛动模式研究

气象科技 1989年第2期17卷 26-34页

作者： S.E.Zebiak M.A.cane 陈兴芳哥伦比亚大学

研制了一个海-气耦合模式,并用于讨论ENSO现象。在没有异常的外部强迫作用的条件下,该耦合模式再现了观测现象的某些关键特征,其中包括增暖事件多以3—4年的不规则时间间隔重新出现。研究表明,平均海平面温度、风和洋流场确定ENSO距平... 详细信息

研制了一个海-气耦合模式,并用于讨论ENSO现象。在没有异常的外部强迫作用的条件下,该耦合模式再现了观测现象的某些关键特征,其中包括增暖事件多以3—4年的不规则时间间隔重新出现。研究表明,平均海平面温度、风和洋流场确定ENSO距平的特征空间结构。距平的锁相(phase-locking)趋势可以用与平均场年变程有关的耦合强度的变化来解释。敏感性研究发现,振荡的振幅和时间尺度对于影响海-气耦合强度的几个参数是敏感的。较强的耦合意味着较大、较长时间尺度的振荡。模式振荡的关键性因素是赤道海水上部含热量的变化率,赤道地区含热量在增暖事件之前增加,在增暖过程中急剧减少。给出了这种变化率和有关El Nino与非El Nino状态之间转化的理论。还讨论了预报El Nino事件的模式结果的含意。

关键词：南方涛动 ENSO 距平耦合模式海-气耦合强迫作用敏感性研究时间尺度含热量变程

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