Full－range nonlinear analysis of fatigue behaviors of reinforced concrete structures by finite element method

The offshore reinforced concrete structures are always subject to cyclic load, such as wave load.In this paper a new finite element analysis model is developed to analyze the stress and strain state of reinforced concrete structures including offshore concrete structures, subject to any number of the cyclic load. On the basis of the anal ysis of the experimental data,this model simplifies the number of cycles-total cyclic strain curve of concrete as three straight line segments,and it is assumed that the stress-strain curves of different cycles in each segment are the same, thus the elastoplastic analysis is only needed for the first cycle of each segment, and the stress or strain corresponding to any number of cycles can be obtained by superposition of stress or strain obtained by the above e lastoplastic analysis based on the cyclic numbers in each segment.This model spends less computer time,and can obtain the stress and strain states of the structures after any number of cycles.The endochronic-damage and ideal offshore concrete platform subject to cyclic loading are experimented and analyzed by the finite element method based on the model proposed in this paper. The results between the experiment and the finite element analysis are in good agreement,which demonstrates the validity and accuracy of the proposed model.

On the Adaptability Range, Self-Selection, and Economic Nature of Biological Evolution

This article employs a combined approach of biology and economics to reveal that biological evolution has an economic nature, evolving towards improved energy efficiency. The orthodox Darwinian theory of evolution describes evolution as the random variation of organisms and their survival through natural selection. In fact, the natural environment itself is a constantly changing context, and the strategy to adapt to this change is to enhance behavioral capabilities, thereby expanding the range and dimensions of behavior. Therefore, the improvement of behavioral capabilities is an important aspect of evolution. The enhancement of behavioral capabilities expands the range of adaptation to the natural environment and increases the space for behavioral choices. Within this space of behavioral choices, some options are more effective and superior to others;thus, the ability to select is necessary to make the improved behavioral capabilities more beneficial to the organism itself. The birth and development of the brain serve the purpose of selection. By using the brain to make selections, at least the “better” behavior will be chosen between two alternatives. Once the better behavior yields better results, and the organism can associate these results with the corresponding behavior, it will persist in this behavior. The persistent repetition of a behavior over generations will form a habit. Habits passed down through generations constitute a new environment, causing the organism’s genes to activate or deactivate certain functions, ultimately leading to genetic changes that are beneficial to that habit. Since the brain’s selection represents the organism’s self-selection, it differs from random variation;it is also a rational selection, choosing behaviors that either obtain more energy or reduce energy consumption. Thus, this evolution possesses an economic nature.

A phenomenological model for plastic flow behavior of rotating band material with a large temperature range

The plastic flow behavior of the rotating band material is investigated in this paper. The rotating band material is processed from H96 brass alloy, which is hardened to a much higher yield strength compared to the annealed one. The dynamically uniaxial compression behavior of the material is tested using the split Hopkinson pressure bar(SHPB) with temperature and strain rate ranging from 297 to 1073 K and500 to 3000 s^(-1), respectively, and a phenomenological plastic flow stress model is developed to describe the mechanical behavior of the material. The material is found to present noticeable temperature sensitivity and weak strain-rate sensitivity. The construction of the plastic flow stress model has two steps. Firstly, three univariate stress functions, taking plastic strain, plastic strain rate and temperature as independent variable, respectively, are proposed by fixing the other two variables. Then, as the three univariate functions describe the special cases of flow stress behavior under various conditions, the principle of stress compatibility is adopted to obtain the complete flow stress function. The numerical results show that the proposed plastic flow stress model is more suitable for the rotating band material than the existing well-known models.

Spring home range and social behavior of Hazel grouse at Changbai Mountain

The spring home range and social behavior of Hazel grouse, (Bonasa bonasia) were studied at Changbai Mountain using radiotelemetry in 1993–94. Flock dissolution and pair formation started in mid-March. Paired males held territories in spring, the area was from 3.2 hm2 to 17.3 hm2 (n=2). Hazel grouse was proved to be monogamous by radiotelemetry work. The overlap of home range between paired No.10 and No.8 was 82.4%. The time of birds being together was 83.0% of the time during the prelaying period (n=53), showing that the pair bond was stable. Unpaired males showed different behavior, held a territory or wandering, and they changed their behavior in early May. The study suggested that unpaired males gave up their reproduction goal, and the acquisition for survival became more important in early May, when female started incubation.

热加工工艺对Beta-C钛合金组织和力学性能的影响

利用Gleeble-3800热模拟试验机在应变速率为20 s^(-1)、变形温度为780~920℃的条件下对Beta-C钛合金试样进行热模拟实验,分析该合金的热变形行为,并在此基础上研究一次镦拔和多次镦拔对Beta-C钛合金棒材显微组织和力学性能的影响。结果表明:当压缩温度为780℃时,热压缩试样出现剪切开裂;当压缩温度为830~920℃时,热压缩试样表面完好,可进行热加工。在相变点以上100℃的β相区进行多次镦拔后,Beta-C钛合金棒材的显微组织可得到明显改善,晶粒更加细化、均匀,综合力学性能得到提高。

Disruptive behavior in the workplace: Challenges for gastroenterology fellows

To assess first-year gastroenterology fellows’ ability to address difficult interpersonal situations in the workplace using objective structured clinical examinations (OSCE).METHODSTwo OSCEs (“distracted care team” and “frazzled intern”) were created to assess response to disruptive behavior. In case 1, a fellow used a colonoscopy simulator while interacting with a standardized patient (SP), nurse, and attending physician all played by actors. The nurse and attending were instructed to display specific disruptive behavior and disregard the fellow unless requested to stop the disruptive behavior and focus on the patient and procedure. In case 2, the fellow was to calm an intern managing a patient with massive gastrointestinal bleeding. The objective in both scenarios was to assess the fellows’ ability to perform their duties while managing the disruptive behavior displayed by the actor. The SPs used checklists to rate fellows’ performances. The fellows completed a self-assessment survey.RESULTSTwelve fellows from four gastrointestinal fellowship training programs participated in the OSCE. In the “distracted care team” case, one-third of the fellows interrupted the conflict and refocused attention to the patient. Half of the fellows were able to display professionalism despite the heated discussion nearby. Fellows scored lowest in the interprofessionalism portion of post-OSCE surveys, measuring their ability to handle the conflict. In the “frazzled intern” case, 68% of fellows were able to establish a calm and professional relationship with the SP. Despite this success, only half of the fellows were successfully communicate a plan to the SP and only a third scored “well done” in a domain that focused on allowing the intern to think through the case with the fellow’s guidance.CONCLUSIONFellows must receive training on how to approach disruptive behavior. OSCEs are a tool that can assess fellow skills and set a culture for open discussion.

Comparison of head size and bite force in two sister species of parrotbills

Background: Brain size is associated with morphological evolution and behavioral flexibility because animals with large brain size tend to utilize new resources and colonize novel environments more successfully.Therefore, animals with larger brain size should possess larger distribution ranges.Brain size is strongly positively correlated with head size in birds, but also with prey size and vocalizations, because individuals with large heads eat large food items and produce high frequency calls.Methods: To test if there exists an association between head morphology and bite performance, we compared head size and bite force in two sympatric sister species of parrotbills, Ashy-throated Parrotbill(Paradoxornis alphonsianus) and Vinous-throated Parrotbill(P.webbianus), which both originated from the Himalayan area, but differ significantly in their distribution ranges.Results: In Guizhou, southwestern China, the Ashy-throated Parrotbill with a restricted distribution range had smaller heads whilst the Vinous-throated Parrotbill with a large distribution range had larger heads.However, there were no differences in head size between Ashy-throated Parrotbills and allopatric populations of Vinous-throated Parrotbills(Jiangxi and Hebei).Furthermore, the tendency of variation in bite force was opposite to that in head size with populations with larger head size having weaker bite force.Conclusions: We showed that there are no differences in head size between the Ashy-throated Parrotbill and allopatric populations of Vinous-throated Parrotbill, which provides evidence for the hypothesis that differences in head size in the Guizhou populations of two sister species are probably the result of local adaptation rather than species-specific.Our study has implications for avian dispersal and adaption related to head size such as diet ecology and vocalizations.

Transport Property of La_(0.67-x)Sm_xSr_(0.33)MnO_3 at Heavy Samarium Doping (0.40≤x≤0.60)

The influence of heavy samarion （Sm） doping （0.40≤x≤0.60） on magnetic and electric properties of La0.67-xSmxSr0.33MnO3 was investigated by measuring the magnetization-temperature （M - T） curves, magnetization-magnetic density （ M - H） curves, resistivity-temperature （ρ- T） curves and magnetoresistivity-temperature （ MR - T） curves of the samples under different temperatures. It is found that, form from long-range ferromagnetic order to spin-cluster glass with the increase of Sm doping amount, the samples transstate and anti-ferromagnetic state; and when x = 0.60, the transport property becomes abnormal under magnetic background; and the magnetic structure changes and extra magnetic coupling induced by doping leads to colossal magnetoresistance effect. The transport mechanism of metallic conduction at low temperature is mainly electron-magneton interaction and can be fitted by the formula ρ = ρ0 ＋ AT^4.5, and the insulatorlike transport mechanism on high temperature range is mainly the function of variable-range hopping and can be fitted by the formula ρ = ρ0exp（T0/T）^1/4. In the formulas above, p is resistivity, T is temperature, and A, ρ0, T0 are constants.

Support from Examiner’s Non-verbal Behavior in Spoken Test

Based on the overall view of communication theory and spoken English language testing system,this paper has conducted a comprehensive and specific observation and research on how examiner non-verbal behavior has affected candidate performance.The research has found out that not only examiner behavior including non-verbal behavior but language testing scenario itself is of communicative nature and examiner’s non-verbal behavior indeed promotes examinee’s test performance,which can help to better understand spoken testing system,examiner non-verbal behavior,and testing environment to promote the development of language speaking test and reflect examinee’s real language competence and ability.

老年结直肠癌高危人群智能语音健康干预效果评价

目的评价60岁及以上结直肠癌高危人群智能语音健康干预效果,为提高该人群知识水平和检查行为依从性提供依据。方法将2020年上海市黄浦区社区60岁及以上居民结直肠癌筛查项目中初筛结果为阳性者782例使用随机数字表法分为干预组和对照组。在1年干预期间,干预组接受2次智能语音电话干预,对照组接受常规健康教育。在干预前后,分别对干预组和对照组进行一次问卷调查,了解其结直肠癌防治的相关知识以及肠镜检查和肛指检查行为改变情况。结果干预组344例,对照组342例,2组对象一般资料比较,差异均无统计学意义(P>0.05)。干预后,干预组较对照组的大肠癌防治知识总分高0.29分,且差异有统计学意义(χ^(2)=5.45,P<0.05),干预组干预后较干预前知识总分提高了0.55分且差异有统计学意义(χ^(2)=60.84,P<0.05)。干预后,干预组的肠镜检查率显著高于对照组(χ^(2)=4.24,P<0.05),干预组干预后较干预前肠镜率显著提高,且差异有统计学意义(χ^(2)=28.25,P<0.05)。结论运用智能语音技术对60岁及以上结直肠癌高危人群进行干预是提高大肠癌防治知识和肠镜检查率的有效手段,可在今后的干预项目中进一步完善和推广。

基于软件机器人的工控靶场应用软件行为模拟

工控靶场为开展工业控制系统(ICS)安全研究提供重要支撑。面向工控靶场关键任务之一的应用软件行为模拟,提出一种软件机器人方法以实现工控靶场应用软件行为的逼真模拟。考虑软件图形界面及软件内在显隐式规则,提出基于尺度不变特征变换(SIFT)图像相似度的软件菜单采集算法及混合状态机模型对应用软件行为进行建模。针对软件机器人的智能化问题,使用深度Q网络(DQN)算法驱动软件机器人对应用软件行为进行自主学习,同时结合多重经验回访和多重目标网络对DQN算法进行优化。实验结果表明:基于DQN的软件机器人能够对工控软件进行有效学习,且优化后的DQN算法自主学习效果更佳。

本科生跨学科考研现象解读——与理想学习者比较的视角

一流本科教育的核心是学习质量,本科生跨学科考研折射的学习问题不容忽视。基于对15名跨学科考研学生的深度访谈,通过主题分析与内容分析归纳其学习投入的具体表征,并与理想学习者进行比较发现,其一,跨学科考研现象具有必然性;其二,跨学科考研中存在“功利型”学生与“学术型”学生两类亚群体,其中“功利型”学生与理想学习者的差距较大;其三,需要特别关注“非本意学习者”及学生的“逃避性投入”。为此,应该通过本科教育制度塑造更多理想学习者,探索建立更为多元且科学的研究生教育选拔方式,同时研究生教育环节应更加注重“学术型”跨学科考研学生的个性化培养。

一种基于行为特征的网络靶场大规模攻击流量生成方法

网络靶场是进行网络安全研究和攻防对抗演练的重要基础设施,生成攻击流量是网络靶场复杂行为模拟的主要组成内容。现有的攻击流量生成方法存在攻击类型有限、生成速率低下、流量内容单一等问题,难以满足网络靶场的应用需求。针对上述问题,本文提出了一种基于行为特征的网络靶场大规模攻击流量生成方法,根据攻击的动作序列和关键载荷等行为特征构建攻击模型,通过动态填充数据包模板的方式高速生成内容可变的大规模攻击流量。在此基础上,本文实现了攻击流量生成系统FATG。实验结果表明,与现有工具相比,FATG在攻击类型、可扩展性、流量内容灵活性以及生成速率等方面均存在优势,能够有效地模拟漏洞利用、拒绝服务等攻击行为支撑对网络靶场各类靶标设备的安全测试。

Sex-specifc seasonal variations of wild boar distance traveled and home range size

Distance traveled and home range size describe how animals move in space.The seasonal variations of these parameters are important to comprehensively understand animal ecology and its connection with reproductive behavior and energy costs.Researchers usually estimate the distance traveled as the sum of the straight-line displacements between sampled positions,but this approach is sensitive to the sampling frequency and does not account for the tortuosity of the animal’s movements.By means of the continuous-time movement modeling which takes into account autocorrelation and tortuosity of movement data,we estimated the distance traveled and monthly home range size of 28 wild boar Sus scrofa and modeled their inter-sexual seasonal variability.Males traveled longer distances and used larger home ranges than females,particularly during the rut in autumn-winter,consistently with the different biological cycles of males and females.Males enlarged their home ranges during the rut but traveled constant average distances along the year,whereas females traveled shorter distances in correspondence with the peak of food resources and birth periods but exhibited constant home range size across seasons.The differences between the seasonal variation patterns of distance traveled and home range size,observed in both sexes,revealed the complex relationship between these two aspects of spatial behavior and the great opportunity of including both distance traveled and home range size in behavioral ecology investigations.We provided a detailed analysis of wild boar spatial behavior and its relationships with the reproductive cycles of males and females,promoting a deeper comprehension of their behavioral ecology.

专利审查中修改超范围的探讨

针对审查实践中对于专利申请文件的修改是否超范围常常存在不一致观点的现象,本文通过分析中日韩三国对申请文件修改的相关规定,找出了三者的异同,并结合具体案例阐述了如何把握修改超范围的尺度。本文指出考虑修改超范围,应兼顾申请人利益和公众利益;我国目前对申请文件的修改较为严格,建议可从技术贡献的角度整体考虑新加入的内容。

Ranging behavior of the François’langur(Trachypithecus francoisi)in limestone habitats of Nonggang,China

Ranging behavior is an important aspect of animal behavior that researchers use to investigate ecological influences on individual behavior.We collected data on the ranging behavior of one group of François’langurs(Trachypithecus francoisi)between August 2003 and July 2004 in a limestone habitat within Nonggang Nature Reserve,China.We evaluated the influences of food availability,water resources and sleeping sites on ranging behavior.During the study period,the total home range size for the study group was 64.5 or(69.3 ha if the lacunae within the borders in which langurs were not observed were included),and the mean daily path length was 541 m.These are well within the range of variation reported in Trachypithecus species.The monthly range size was between 9.8 and 23.3 ha,and monthly range size correlated negatively with young leaf availability.The langurs tended to use a larger range size during young leaf-lean periods.The langurs did not use their home range uniformly,and 74%of their activities occurred within 35%of their home range.The most heavily used quadrats in the home range were located near the most frequently used sleeping sites,suggesting that sleeping sites have a significant influence on the ranging behavior of François’langurs in limestone habitats.

SPOC+行为导向教学法对手术室实习护士自我效能、CIRN评分及出科考试成绩的影响

目的:探讨应用小规模限制性在线课程(SPOC)联合行为导向教学法对手术室实习护士自我效能、中国注册护士核心能力量表(CIRN)评分及出科考试成绩的影响。方法:选取2022年1月—2023年1月于德阳市人民医院手术室实习的94名实习护士作为研究对象,按照抛硬币法将进入A区手术室的实习护士作为实验组,进入B区手术室的实习护士为对照组,每组各47人。对照组实习护士应用传统临床带教法,实验组实习护士在对照组基础上应用SPOC联合行为导向教学法,比较两组实习护士自我效能[一般自我效能感量表(GSES)评分]、护士核心能力(CIRN评分)、出科考试成绩及护理满意度。结果:培训后,实验组实习护士GSES总分、CIRN各维度评分、理论考核成绩、实践考核成绩及教学满意度均高于对照组,差异均有统计学意义(t=4.655、9.787、6.912、9.476、7.775、2.595、6.874、7.131、9.931、9.776,χ^(2)=4.681;P<0.05)。结论:采用SPOC联合行为导向教学法可显著提升手术室实习护士自我效能、CIRN评分、出科考核成绩及教学满意度。

城市排污行为分析下的城市水环境污染范围确认方法研究

针对城市水环境污染范围确认精度及效率低下问题,提出城市排污行为分析下的城市水环境污染范围确认方法。通过分析城市排污行为特征,采用Contourlet变换方法,对城市水环境遥感图像展开两次细节增强处理,提高水环境遥感图像的清晰度,为后续的污染范围确认提供可靠依据。将增强后的遥感图像输入AFR-LinkNet网络中,获取图像特征图,动态确认水环境污染范围。实验结果表明,所提方法可有效分析污水排放系数在不同季节内的变化情况,遥感图像的清晰度较高且确认时间较短,具有较高的精度和效率。

双参保守复混沌系统的构建及偏置增压控制

基于经典保守混沌系统的结构,构造了一个双参数保守混沌系统,能够产生复杂动力学现象。通过理论分析和多种数值仿真方法,研究了系统结构参数和外力参数对混沌性、保守性、平衡状态和稳定性的影响。结果表明,随着参数的变化,系统相体积保持守恒,呈现混沌、周期运动等现象,并证明了参数对平衡状态的影响。此外,通过虚实分离的方法构造了复系统,并研究了其动力学特性,发现实混沌系统所构造的复系统中,同样具有混沌性和保守性,且具有大参数范围混沌现象。设计了控制器,使系统产生偏置增压现象,并可对信号极性进行控制。最后,设计了系统电路并进行了仿真,结果与理论相符,证明了混沌系统的物理可行性。

基于空气检测的吸油烟机设计与开发

目前厨房因燃气泄漏造成的安全事故防不胜防,同时,室内PM2.5颗粒浓度超标会危害用户的健康,为了解决这个问题,设计了一种可以检测空气质量的吸油烟机。该机基于SolidWorks三维软件进行整机的结构组成,并借助Keil C51编程软件进行电路控制系统设计。首先,阐述该机的设计原理与开发流程;其次,对该机的结构组成进行了介绍;然后介绍整机的控制系统设计;最后,通过在实验室用烟气分析仪及激光粉尘仪检测,当一氧化碳浓度大于或等于允许值30 mg/m^(3)或PM2.5浓度大于或等于允许值50μg/m^(3)时,自动开启油烟机运转,快速排出有害污染气体,直至空气质量小于或等于允许值时将自动关闭油烟机,无需人工操作。与现有技术相比,本机更具智能化,通过空气质量检测模块的作用,能够实时监控用户厨房有害气体的浓度,当有害气体超标时,由蜂鸣器发出警报,自动启动吸油烟机并加大转速排出有害气体,防止用户因有害气体中毒的现象。