Cloudless-Training:基于serverless的高效跨地域分布式ML训练框架

跨地域分布式机器学习(ML)训练能够联合多区域的云资源协作训练,可满足许多新兴ML场景(比如大型模型训练、联邦学习)的训练需求。但其训练效率仍受2方面挑战的制约。首先,多区域云资源缺乏有效的弹性调度,这会影响训练的资源利用率和性能;其次,模型跨地域同步需要在广域网(WAN)上高频通信,受WAN的低带宽和高波动的影响,会产生巨大通信开销。本文提出Cloudless-Training,从3个方面实现高效的跨地域分布式ML训练。首先,它基于serverless计算模式实现,使用控制层和训练执行层的2层架构,支持多云区域的弹性调度和通信。其次,它提供一种弹性调度策略,根据可用云资源的异构性和训练数据集的分布自适应地部署训练工作流。最后,它提供了2种高效的跨云同步策略,包括基于梯度累积的异步随机梯度下降(ASGD-GA)和跨云参数服务器(PS)间的模型平均(MA)。Cloudless-Training是基于OpenFaaS实现的,并被部署在腾讯云上评估,实验结果表明Cloudless-Training可显著地提高跨地域分布式ML训练的资源利用率(训练成本降低了9.2%~24.0%)和同步效率(训练速度最多比基线快1.7倍),并能保证模型的收敛精度。

Consideration of Postgraduate Training under the Cross Field of Medical Information and Engineering

The slogan of“Combination of medicine and engineering”proposed in“Made in China 2025”has aroused great attention to higher engineering education.However,it is a difficult problem and challenge for schools and educators to effectively adapt to the economic and social development,train new medical and engineering talents,and explore and cultivate new subject growth points.In order to deal with engineering change and a new round of scientific and technological revolution,facing the challenge of new engineering construction.This paper will combine the reality and characteristics of colleges and universities,analyze the problems existing in the current medical engineering cross-graduate training,and put forward countermeasures and suggestions to promote the progress and development of science and technology in colleges and universities.

Training theory and practice of crossing cultural awareness in college English teaching

English is the current most widely used international language of communication, with the improvement of China＇ s comprehensive national strength, participation in the exchange, cooperation and increase trade opportunities for the international community, particularly the WTO, Beijing ＇s successful Olympic bid, the Shanghai World Expo, several major events more and more people are realizing the importance of English practical applications. Now students acquire decent rules of successful communication in English, and this should be the starting point and final destination of English teaching. Therefore, in the process of teaching English, the penetration of the language and cultural knowledge, cross-cultural communication awareness training must cause concern and attention of English teachers to improve students ＇ intercultural communication content acumen, thus to improve students＇ English communication in practice capacity.

Improvement of heat-tolerance by training I. Evaluation of effects of combined of march and cross-country race on heat-tolerance

in order to improve the acquired level of heat acclimatization (HA) by training, on the basis of singlemode march training (SMT) or single-mode cross-country race training (SCT) , combined training method of march and cross-country race in the heat was adopted in this experiment ,and the effect of the training on heat tolerance was analyzed. Eight young males were asked to perform a simulated SMT and SCT for 90 min on a treadmill in a hot climate chamber (Td 32. 7℃ , WBGT 28. 4℃ ) once daily for 10 to 12 d within two weeks. The results showed that rectal temperature (Tr) was reduced by 0. 61℃ , heart rate (Hr) by 8. 5 b/min,sweat volume (SV)by 0. 220 kg, physiological strain index (PSI)by 0. 620,systolic pressure (SP)and diastolic pressure (DP) had a little change, pulse pressure (PP) and stroke volume (StV) increased , and cardiac output (CO) decreased a little at the middle stage and increased at the late stage due to Hr change. The standardized bicycle ergometer test (SBE test) in the heat (Td 37℃)has proved that these physiological indexes post-training had significant improvements ,as compared with those pre-training, suggesting that the combined training could raise heat-tolerance and was superior to the SMT in improving acquired heat acclimatization in same training duration and times , and to the SCT in regulating body temperature and cardiovascular function and in prolonging heat tolerance duration.

Improvement of heat-tolerance by training Ⅱ. Evaluation of effects of cross-country race and heat-bath training on heat-tolerance

This paper reports the effects of two trainings-5 km cross-country race and 15 min heat-bath on theimprovement of heat-tolerance. All subjects of the training group were asked to perform a training once daily for 10to 12 d within two weeks. The results proved that the cross-country race training both in the artificial hot chamberand on the drill ground of troop could obtain evident training-adaptation. The rectal temperature, heart rate, andsweat volume reduced by 0. 39℃, 13. 2 b/min and 338 g during training in field, respectively. In the same period ofcross-country race training, the normal military exercises, labours and natural heat acclimatization in the summercould only raise slightly the level of heat acclimatization in soldiers. Heat-bath training could reduce rectal temperature by 0. 6℃ during immersion in hot water, however, the level of heat-tolerance in a hot climatic chamber was inferior to that attained by cross-country race, march and running training.

Cross-Cultural Communication Skills Training Strategies in College English Education

With the increasing exchange of countries,the role of English as an international official language has become more and more prominent.First and foremost,how to improve the comprehensive quality of students in the teaching process and further en hance students'cross-cultural communication ability is what teachers should think about in the course of teaching.English,as the second language of students,has its own language characteristics and cultural backgrounds,starting from the root of culture,which lay the foundation for students'cross-cultural communication abilities,but also require a better environment for students to master English.After all,English learning is not only about reading and writing,but also about the comprehensive use of hearing and un derstanding.This paper mainly discusses the value of cross-cultural communicative ability training in college English education and the strategy of cross-cultural communicative ability in college English education.

Changes in brain activation patterns according to cross-training effect in serial reaction time task An functional MRI study

Cross-training is a phenomenon related to motor learning, where motor performance of the untrained limb shows improvement in strength and skill execution following unilateral training of the homologous contralateral limb. We used functional MRI to investigate whether motor performance of the untrained limb could be improved using a serial reaction time task according to motor sequential learning of the trained limb, and whether these skill acquisitions led to changes in brain activation patterns. We recruited 20 right-handed healthy subjects, who were randomly allocated into training and control groups. The training group was trained in performance of a serial reaction time task using their non-dominant left hand, 40 minutes per day, for 10 days, over a period of 2 weeks. The control group did not receive training. Measurements of response time and percentile of response accuracy were performed twice during pre- and post-training, while brain functional MRI was scanned during performance of the serial reaction time task using the untrained right hand. In the training group, prominent changes in response time and percentile of response accuracy were observed in both the untrained right hand and the trained left hand between pre- and post-training. The control group showed no significant changes in the untrained hand between pre- and post-training. In the training group, the activated volume of the cortical areas related to motor function （i.e., primary motor cortex, premotor area, posterior parietal cortex） showed a gradual decrease, and enhanced cerebellar activation of the vermis and the newly activated ipsilateral dentate nucleus were observed during performance of the serial reaction time task using the untrained right hand, accompanied by the cross-motor learning effect. However, no significant changes were observed in the control group. Our findings indicate that motor skills learned over the 2-week training using the trained limb were transferred to the opposite homologous limb, and motor skill acquisition of the untrained limb led to changes in brain activation patterns in the cerebral cortex and cerebellum.

基于交叉熵的安全Tri-training算法

半监督学习方法通过少量标记数据和大量未标记数据来提升学习性能.Tri-training是一种经典的基于分歧的半监督学习方法,但在学习过程中可能产生标记噪声问题.为了减少Tri-training中的标记噪声对未标记数据的预测偏差,学习到更好的半监督分类模型,用交叉熵代替错误率以更好地反映模型预估结果和真实分布之间的差距,并结合凸优化方法来达到降低标记噪声的目的,保证模型效果.在此基础上,分别提出了一种基于交叉熵的Tri-training算法、一个安全的Tri-training算法,以及一种基于交叉熵的安全Tri-training算法.在UCI(University of California Irvine)机器学习库等基准数据集上验证了所提方法的有效性,并利用显著性检验从统计学的角度进一步验证了方法的性能.实验结果表明,提出的半监督学习方法在分类性能方面优于传统的Tri-training算法,其中基于交叉熵的安全Tri-training算法拥有更高的分类性能和泛化能力.

Effect of landform on aerodynamic performance of high-speed trains in cutting under cross wind

The effects of the different landforms of the cutting leeward on the aerodynamic performance of high-speed trains were analyzed based on the three-dimensional, steady, and incompressible Navier-Stokes equation and k-e double-equation turbulent model. Results show that aerodynamic forces increase with the cutting leeward slope decreasing. The maximum adding value of lateral force, lift force, and overturning moment are 147%, 44.3%, and 107%, respectively, when the slope varies from 0.67 to -0.67, and the changes in the cutting leeward landform have more effects on the aerodynamic performance when the train is running in the line No. 2 than in the line No. 1. The aerodynamic forces, except the resistance force, sharply increase with the slope depth decreasing. By comparing the circumstance of the cutting depth H=-8 m with that of H=8 m, the resistance force, lateral force, lift force, and overturning moment increase by 26.0%, 251%, 67.3% and 177%, respectively. With the wind angle increasing, the resistance force is nonmonotonic, whereas other forces continuously rise. Under three special landforms, the changes in the law of aerodynamic forces with the wind angle are almost similar to one another.

Detached-eddy simulation of flow around high-speed train on a bridge under cross winds

In order to describe an investigation of the flow around high-speed train on a bridge under cross winds using detached-eddy simulation(DES), a 1/8th scale model of a three-car high-speed train and a typical bridge model are employed, Numerical wind tunnel technology based on computational fluid dynamics(CFD) is used, and the CFD models are set as stationary models. The Reynolds number of the flow, based on the inflow velocity and the height of the vehicle, is 1.9×10~6. The computations are conducted under three cases, train on the windward track on the bridge(WWC), train on the leeward track on the bridge(LWC) and train on the flat ground(FGC). Commercial software FLUENT is used and the mesh sensitivity research is carried out by three different grids: coarse, medium and fine. Results show that compared with FGC case, the side force coefficients of the head cars for the WWC and LWC cases increases by 14% and 29%, respectively; the coefficients of middle cars for the WWC and LWC increase by 32% and 10%, respectively; and that of the tail car increases by 45% for the WWC whereas decreases by 2% for the LWC case. The most notable thing is that the side force and the rolling moment of the head car are greater for the LWC, while the side force and the rolling moment of the middle car and the tail car are greater for the WWC. Comparing the velocity profiles at different locations, the flow is significantly influenced by the bridge-train system when the air is close to it. For the three cases(WWC, LWC and FGC), the pressure on the windward side of train is mostly positive while that of the leeward side is negative. The discrepancy of train's aerodynamic force is due to the different surface area of positive pressure and negative pressure zone. Many vortices are born on the leeward edge of the roofs. Theses vortices develop downstream, detach and dissipate into the wake region. The eddies develop irregularly, leading to a noticeably turbulent flow at leeward side of train.

Analysis and Study on the Effect of PNF Stretching and Resistance Training on the Rehabilitation of Superior Chiasma Syndrome

In this paper,18 subjects with superior chiasma syndrome were analyzed and studied according to the inducement and correction method of superior chiasma syndrome by questionnaire survey,literature review and experimental research.To explore the effect of bad posture on the posture of patients,and to explore the effect of PNF stretching,anti-resistance training and manual loosening on the rehabilitation of patients with superior chiasma.Methods:the subjects were divided into three experimental groups,A,B and C,for 6 weeks,4 times a week for resistance training and PNF stretching training.It has been proved that the population with chest ambushes for a long time will cause the imbalance of muscle strength of shoulder,neck and chest,abnormal physiological curvature of cervical vertebrae and thoracic vertebrae,and induce chronic injury of shoulder and neck muscles and soft tissue,which will lead to symptoms of superior chiasma syndrome.According to the designed rehabilitation training experiment,PNF stretching training and anti-resistance training were carried out for the shoulder and neck muscles which caused superior chiasma syndrome,and the rehabilitation effect was very significant,which was obviously better than that of PNF stretching or resistance training alone.Therefore,PNF stretching and resistance training should be fully combined in rehabilitation training to improve the posture problem in order to achieve twice the result with half the effort.

Application of cross-migration theory in limb rehabilitation of stroke patients with hemiplegia

BACKGROUND Stroke is a common cause of neurological dysfunction,often resulting in hemiplegia.Thus,rehabilitation of limb function in stroke patients is an important step towards accelerating recovery and improving quality of life.AIM To investigate whether unilateral strength training in hemiplegic stroke patients could lead to cross-migration,an increase in bilateral muscle strength,and an improvement in lower limb motor function.METHODS We randomly divided 120 patients with hemiplegic stroke into two groups:Eexperimental and control groups,with 60 patients in each group.Both groups received routine rehabilitation treatment,while the experimental group additional-ly received ankle dorsiflexion resistance training on the healthy side for 6 wk.We measured the maximum voluntary contract(MVC),changes in surface electromyography(EMG),and the lower limb motor function using the simplified Fugl Meyer Motor Function Assessment Scale(FMA)before and within 1 wk after training.RESULTS The FMA score in the experimental group improved significantly compared to both their pre-training score and the control group's post-training score(P<0.05).The integrated EMG of the anterior tibialis muscle and pulmonary intestine muscle in the experimental group were significantly different after training than before(P<0.05).Furthermore,the MVC of the anterior tibialis muscle on both the healthy and affected sides and the MVC of the pulmonary intestine muscle on both sides showed significant improvement compared with before training and the control group(P<0.05).CONCLUSION Our findings suggest that ankle dorsiflexion resistance training on the healthy side in hemiplegic stroke patients can increase strength in the opposite tibialis anterior muscle and antagonist's muscle,indicating a cross-migration phenomenon of strength training.Furthermore,this type of training can also improve lower limb motor function,providing a new exercise method for improving early ankle dorsiflexion dysfunction.

Crossed Micro-bands in the Martensite Variant Pairs of a Thermomechanically Trained Cu-Zn-Al Alloy

The crossed micro-bands in the martensite variant pairs of a thermomechanically trained Cu25.66Zn-4.02Al (wt-%) alloy have been studied. It was found that the micro-bands pass through the interface from one martensite variant to another and their orientation inside different variants is distinct, which would remain in the parent phase after the reverse transformation and play an important role in the formation of preferential martensite. In fact, the crossed micro-bands are micro-twins for accommodating the stress fields generated during thermomechanically training

30所三级医院开展ICU护士入职培训的现况调查

目的:调查三级医院开展ICU护士入职培训现况,为探索更有效的ICU护士入职培训提供参考。方法:2022年7月—8月,采用便利抽样法选取全国11个省份30所三级医院57个ICU的护理管理者及583名ICU护士作为调查对象,使用自行设计的ICU护士入职培训情况调查问卷进行调查。结果:参与调查的57个(100.0%)ICU均制定了新护士入职培训计划并规定经过带教期后方可独立上岗,但培训形式多样、带教期时长尚不统一,仅32个(56.1%)ICU有资质准入制度和相关考核;52名(91.2%)护理管理者将规范化培训后的新护士视为最优选;应届毕业生新护士占总护士人数的比例与非计划性拔管的发生率呈正相关(r=0.341,P<0.05)。参与调查的583名护士中364名(62.4%)认为3~6个月的带教时长最为合适,339名(58.1%)倾向于毕业后先掌握普通患者护理技能,再入职ICU;回归分析显示入职培训期间ICU护士适应工作压力的影响因素为ICU类型、临床实践带教形式与带教时长。结论:目前ICU资质准入制度仍不完善,入职培训尚无统一的方案,带教时长仍需要进一步讨论,未来仍需要制定纲领性文件指导ICU开展护士入职培训工作。

Cross Fit训练对我国青少年身体素质影响的Meta分析

目的:系统评价Cross Fit训练对我国青少年身体素质的影响效果,并对其内在机制进行探讨分析。方法:通过Pub Med、Web of Science、CNKI等数据库筛选15篇符合要求的文献纳入Meta分析。运用Cochrance系统评价工具对纳入文献进行方法学质量和发表偏倚性研究。通过Rev Man5.4统计软件对纳入文献采用固定效应模型进行统计学分析。结果:Meta分析结果显示Cross Fit训练对青少年肺活量、50m跑、立定跳远、引体向上、仰卧起坐成绩的提升较对照组相比有显著优势。对青少年身高、体重、BMI、坐位体前屈、1000m跑、800m跑成绩的提升较对照组相比并无显著优势。结论:Cross Fit训练可以有效帮助青少年提高肺活量、速度素质以及力量素质。而对于身体形态、柔韧素质、耐力素质的提升与常规训练模式相比并不存在显著优势。建议将Cross Fit训练与常规的素质练习有效结合,充分发挥该训练模式的优势,以提高青少年各项身体素质。

基于产教融合的跨境电子商务专业校企协同育人模式研究

随着经济全球化的发展,跨境电子商务已经成为了国际贸易的重要形式,为推动国际贸易和经济发展提供了新的机遇和挑战。跨境电子商务的发展对人才的需求越来越高,如何培养高素质的跨境电子商务人才已经成为了当前教育领域的一个热点问题。文章从产教融合的角度出发,结合校企协同育人的模式,对跨境电子商务专业人才培养模式进行了探讨和研究。通过分析当前跨境电子商务市场的现状和发展趋势,总结了跨境电子商务人才的基本要求和能力素质,从而提出了基于产教融合的校企协同育人模式。在模式实施中,需要建立稳定的校企合作关系,建设完善的实践基地,实现课程的有效对接,并注重实践教学的重要性。通过研究,旨在为跨境电子商务专业人才的培养提供参考,为推动产教融合的校企协同育人模式提供借鉴。

青少年越野滑雪运动员有氧耐力训练研究

2022年北京冬奥会上,中国冰雪健儿斩获了9金4银2铜,我国冰雪运动从弱项发展为均衡。其中,越野滑雪项目有了极大的突破,这与科学训练有着非常密切的联系。科学的有氧耐力训练法能够在有效激发运动员运动潜能的同时,增强运动员的综合能力,以此确保青少年越野滑雪运动员可以在正式比赛中取得优异成绩。该文就青少年越野滑雪运动员有氧耐力训练展开相应研究,从越野滑雪运动概述入手,简述越野滑雪运动员有氧耐力基本要求,并详细介绍了青少年越野滑雪运动员有氧耐力训练的方法。

基于视觉注意力的图文跨模态情感分析

针对单模态情感分析无法完全捕获情感信息的问题,提出一种图像和文本跨模态情感分析模型(BERT-VistaNet),该模型没有直接使用视觉信息作为特征,而是利用视觉信息作为对齐方式,使用注意力机制指出文本中重要的句子,得到基于视觉注意力的文档表示。对于视觉注意力无法完全覆盖的文本内容,使用BERT模型对文本进行情感分析,得到基于文本的文档表示,将特征进行融合应用于情感分类任务。在Yelp公开餐厅数据集上,该模型相比基线模型TFN-aVGG,准确率提高了43%,相比VistaNet模型准确率提高了1.4%。

跨线条件下城市轨道交通列车交路计划优化方法

跨线运营是城市轨道交通重点发展方向。针对跨线条件下列车交路计划编制问题,通过构造乘客出行时空网络图准确刻画复杂交路下的客流行为,建立以最小化列车走行公里与乘客出行时间成本为目标的混合整数规划模型。模型以列车交路方案、开行比例与频率为决策变量,并针对跨线交路与本线交路的行车冲突,考虑非等间隔发车,确定列车发车时刻。设计基于交路及开行频率搜索与运行间隔协调的定制分解算法。案例结果表明,列车跨线方向与乘客换乘主方向一致时,跨线交路可同时提升企业运营与乘客出行效益。换乘出行导致的断面客流量差异是跨线交路开行方案设置的主要依据。研究结论可为运营企业制定列车交路计划提供依据,有助于提高网络运输效率。

规范化培训护士培训负荷与工作嵌入水平的相关性研究

目的:分析规范化培训护士培训负荷与工作嵌入水平的现状,并探讨两者之间的相关性。方法:2022年4月,便利选取福建省某三级甲等医院246名规范化培训护士作为研究对象,应用临床护士培训负荷量表和护士职业嵌入量表进行调查。结果:规范化培训护士培训负荷总分为(61.50±17.51)分,工作嵌入总分为(64.93±12.59)分。相关性分析结果显示,培训负荷总分及各维度得分与工作嵌入总分及各维度得分均呈负相关(P<0.05)。结论:规范化培训护士培训负荷处于中等水平,工作嵌入处于中等偏上水平,降低规范化培训护士的培训负荷将有效提升其工作嵌入水平。