3-Turns教学法在实践共同体促进深度学习中的应用

在电气工程专业实践教学过程中凝练出由Turn up、Turn away、Turn back等环节组成的3-Turns教学法。经过多轮的实践应用,3-Turns教学法在实践共同体中提供了一个兼具解释性与可操作性的教学样例。研究发现,3-Turns教学法对实践共同体促进工科生深度学习起到了提质增效的作用;3-Turns教学法为工程实践学习情境的强化设计提供了理论依据与经验支持。该研究验证了基于3-Turns教学法的实践共同体促进工科生深度学习的有效性,为助力工科人才培养质量的持续提升做出了积极的探索与实践。

Domestic clothing market turns from decline to increase

From January to February,policies and measures to stabilize the economy were further effective,combined with factors such as the fading impact of the pandemic,and the resumption of production and business in China's garment industry accelerated steadily.The domestic garment market changed from a decline to an increase,and the market vitality continued to recover.However,due to the weakening of international market demand,order transfer and other reasons,China's garment exports are from positive growth to a significant decline In general,with domestic sales recovering and exports declining,the growth rate of major indicators such as production,benefit and investment of the garment industry showed an obvious negative growth trend.There are still great pressures and challenges for the industry to maintain a stable recovery.

Case Retrieval Strategy of Turning Process Based on Grey Relational Analysis

To solve the problem of long response time when users obtain suitable cutting parameters through the Internet based platform,a case-based reasoning framework is proposed.Specifically,a Hamming distance and Euclidean distance combined method is designed to measure the similarity of case features which have both numeric and category properties.In addition,AHP(Analytic Hierarchy Process)and entropy weight method are integrated to provide features weight,where both user preferences and comprehensive impact of the index have been concerned.Grey relation analysis is used to obtain the similarity of a new problem and alternative cases.Finally,a platform is also developed on Visual Studio 2015,and a case study is demonstrated to verify the practicality and efficiency of the proposed method.This method can obtain cutting parameters which is suitable without iterative calculation.Compared with the traditional PSO(Particle swarm optimization algorithm)and GA(Genetic algorithm),it can obtain faster response speed.This method can provide ideas for selecting processing parameters in industrial production.While guaranteeing the characteristic information is similar,this approach can select processing parameters which is the most appropriate for the production process and a lot of time can be saved.

High-sensitive state perception method for inverter-fed machine turn insulation based on FrFT-Mel

Amidst the swift advancement of new power systems and electric vehicles,inverter-fed machines have progressively materialized as a pivotal apparatus for efficient energy conversion.Stator winding turn insulation failure is the root cause of inverter-fed machine breakdown.The online monitoring of turn insulation health can detect potential safety risks promptly,but faces the challenge of weak characteristics of turn insulation degradation.This study proposes an innovative method to evaluate the turn insulation state of inverter-fed machines by utilizing the fractional Fourier transform with a Mel filter(FrFT-Mel).First,the sensitivity of the high-frequency(HF)switching oscillation current to variations in turn insulation was analyzed within the fractional domain.Subsequently,an improved Mel filter is introduced,and its structure and parameters are specifically designed based on the features intrinsic to the common-mode impedance resonance point of the electrical machine.Finally,an evaluation index was proposed for the turn insulation state of inverter-fed machines.Experimental results on a 3kW permanent magnet synchronous machine(PMSM)demonstrate that the proposed FrFT-Mel method significantly enhances the sensitivity of turn insulation state perception by approximately five times,compared to the traditional Fourier transform method.

Analysis on the turning point of dynamic in-plane compressive strength for a plain weave composite

Experimental investigations on dynamic in-plane compressive behavior of a plain weave composite were performed using the split Hopkinson pressure bar. A quantitative criterion for calculating the constant strain rate of composites was established. Then the upper limit of strain rate, restricted by stress equilibrium and constant loading rate, was rationally estimated and confirmed by tests. Within the achievable range of 0.001/s-895/s, it was found that the strength increased first and subsequently decreased as the strain rate increased. This feature was also reflected by the turning point(579/s) of the bilinear model for strength prediction. The transition in failure mechanism, from local opening damage to completely splitting destruction, was mainly responsible for such strain rate effects. And three major failure modes were summarized under microscopic observations: fiber fracture, inter-fiber fracture, and interface delamination. Finally, by introducing a nonlinear damage variable, a simplified ZWT model was developed to characterize the dynamic mechanical response. Excellent agreement was shown between the experimental and simulated results.

Evolution and Prospects of Russia’s“Turn to the East”

With the escalation of the Ukraine crisis,Russia’s policy of“Turn to the East”has evolved into“Turn to the Non-West”at an accelerated pace.Involving both a shift of focus in diplomacy and economics and the“de-Westernization”in financial and ideological areas,it has become a strategy to break through Western diplomatic and economic blockade.The transition will continue in the medium term,but adjustments or twists and turns are likely under the influence of internal and external factors.

DER SPATIAL TURN IN DEN KLASSISCHEN ALTERTUMSWISSENSCHAFTEN(UND SPEZIELL IN DER EPIGRAPHIK)

Since the 1990s the so-called spatial turn has brought back space and topography into the discussion within historical studies,particular ancient studies.This survey reviews current trends and developments within the field and offers some perspectives on possible future developments related to space,material,objects,their agency,and frames.

HCB-turn热风干燥器在纸机改造中的应用

由于市场、成本、车速、纸张品质等原因,需要对背面涂布段进行优化改造,这时候加装HCB-turn热风干燥器则是最佳的选择之一,因为它比常规纸幅运行节省1/3的安装空间,且适用于所有纸种,对纸张和涂层能够有高效的干燥和无污染的转向。

Numerical Study of a Three-Dimensional Laminar Flow in a Rectangular Channel with a 180-Degree Sharp Turn

This study presents a numerical analysis of three-dimensional steady laminar flow in a rectangular channel with a 180-degree sharp turn. The Navier-Stokes equations are solved by using finite difference method for Re = 900. Three-dimensional streamlines and limiting streamlines on wall surface are used to analyze the three-dimensional flow characteristics. Topological theory is applied to limiting streamlines on inner walls of the channel and two-dimensional streamlines at several cross sections. It is also shown that the flow impinges on the end wall of turn and the secondary flow is induced by the curvature in the sharp turn.

TURNING LIGNIN INTO VALUABLE PRODUCTS

In a study published in Nature Catalysis on May 28,Chinese scientists unveiled a nove l approach to transforming lignin,a major component of woody biomass,into valuable chemical products(doi:10.1038/s41929-024-01165-w).This discovery could pave the way for more sustainable and efficient use of renewable resources.

利用车载GNSS轨迹大数据的U-Turn道路结构信息获取方法

随着智慧交通和精细化导航技术的迅速发展,人们对道路地图要素的覆盖度、精准度、丰富度与新鲜度需求越来越高,而U-Turn作为城市路网连通关系的重要因素,成为道路地图更新的重要内容之一。现有专业道路测绘模式对U-Turn数据存在采集成本高、更新周期长、数据处理繁等问题,导致U-Turn数据无法满足智慧交通导航需求。本文采用车载GNSS轨迹大数据,提出了一种U-Turn道路结构信息获取方法。首先通过轨迹跟踪提取车辆掉头点对与行为;然后利用DBSCAN聚类算法提取U-Turn掉头类簇;再依据U-Turn流量占比等特征构建支持向量机二分模型,自适应剔除违规掉头类簇,并区分出U-Turn结构有无通行时间限制;最后根据掉头类簇在道路结构中的分布特征,识别U-Turn位置与空间结构。试验以武汉市滴滴网约车GNSS轨迹,对江汉区183个路段采用本文方法进行探测,U-Turn结构信息识别召回率为88.3%,精确率为87.6%,位置识别的横向和纵向精度分别为3.40 m和5.90 m,试验结果表明本文方法可以有效地从车载GNSS轨迹数据中获取U-Turn的位置与结构类型,为U-Turn数据获取提供了周期短、成本低的有效解决方案。

A theoretical and deep learning hybrid model for predicting surface roughness of diamond-turned polycrystalline materials

Polycrystalline materials are extensively employed in industry.Its surface roughness significantly affects the working performance.Material defects,particularly grain boundaries,have a great impact on the achieved surface roughness of polycrystalline materials.However,it is difficult to establish a purely theoretical model for surface roughness with consideration of the grain boundary effect using conventional analytical methods.In this work,a theoretical and deep learning hybrid model for predicting the surface roughness of diamond-turned polycrystalline materials is proposed.The kinematic–dynamic roughness component in relation to the tool profile duplication effect,work material plastic side flow,relative vibration between the diamond tool and workpiece,etc,is theoretically calculated.The material-defect roughness component is modeled with a cascade forward neural network.In the neural network,the ratio of maximum undeformed chip thickness to cutting edge radius RT S,work material properties(misorientation angle θ_(g) and grain size d_(g)),and spindle rotation speed n s are configured as input variables.The material-defect roughness component is set as the output variable.To validate the developed model,polycrystalline copper with a gradient distribution of grains prepared by friction stir processing is machined with various processing parameters and different diamond tools.Compared with the previously developed model,obvious improvement in the prediction accuracy is observed with this hybrid prediction model.Based on this model,the influences of different factors on the surface roughness of polycrystalline materials are discussed.The influencing mechanism of the misorientation angle and grain size is quantitatively analyzed.Two fracture modes,including transcrystalline and intercrystalline fractures at different RTS values,are observed.Meanwhile,optimal processing parameters are obtained with a simulated annealing algorithm.Cutting experiments are performed with the optimal parameters,and a flat surface finish with Sa 1.314 nm is finally achieved.The developed model and corresponding new findings in this work are beneficial for accurately predicting the surface roughness of polycrystalline materials and understanding the impacting mechanism of material defects in diamond turning.

Integral Event-Triggered Attack-Resilient Control of Aircraft-on-Ground Synergistic Turning System With Uncertain Tire Cornering Stiffness

This article proposes an integral-based event-triggered attack-resilient control method for the aircraft-on-ground(AoG) synergistic turning system with uncertain tire cornering stiffness under stochastic deception attacks. First, a novel AoG synergistic turning model is established with synergistic reverse steering of the front and main wheels to decrease the steering angle of the AoG fuselage, thus reducing the steady-state error when it follows a path with some large curvature. Considering that the tire cornering stiffness of the front and main wheels vary during steering, a dynamical observer is designed to adaptively identify them and estimate the system state at the same time.Then, an integral-based event-triggered mechanism(I-ETM) is synthesized to reduce the transmission frequency at the observerto-controller end, where stochastic deception attacks may occur at any time with a stochastic probability. Moreover, an attackresilient controller is designed to guarantee that the closed-loop system is robust L2-stable under stochastic attacks and external disturbances. A co-design method is provided to get feasible solutions for the observer, controller, and I-ETM simultaneously. An optimization program is further presented to make a tradeoff between the robustness of the control scheme and the saving of communication resources. Finally, the low-and high-probability stochastic deception attacks are considered in the simulations. The results have illustrated that the AoG synergistic turning system with the proposed control method follows a path with some large curvature well under stochastic deception attacks. Furthermore,compared with the static event-triggered mechanisms, the proposed I-ETM has demonstrated its superiority in saving communication resources.

Paradigm Shifts in Translation Studies： Focus on Linguistic, Cultural, Social and Psychological Turns

Translation has been the subject of a variety of research and conflicts among theorists. This fact that gives Thomas Samuel Kuhn＇s paradigm theory is pertinent to the present study. Kuhn is an American philosopher of Science. In his book The Structure of Scientific Revolutions, he proposes his paradigm theory which plays a great role in the development of sociology and philosophy of Science. According to Kuhn （1970）, paradigm originates from one or some famous people＇s achievements, and for these achievements to be considered as paradigms, two major characteristics must be met as will be clarified in this paper. This study is an attempt to outline the scope of the disciplines of Translation Studies （TS）, to give some indication of the kind of work that has been done so far. It is an attempt to demonstrate that TS is a discipline in its own right. It is a vastly complex field with many far-reaching ramifications. This study discusses the relationships between the changing definitions of translation and the turns of translation studies.

A CLEAR PICTURE OF CHINA——China International Publishing Group turns 70

China International Publishing Group(CIPG)served as one of the first windows for the outside world to get to know China.Its predecessor,the International News Division of the National Press Administration of the Central Government,was founded the same day as the People’s Republic of China(PRC)on October 1,1949.Qiao Guanhua,who later became Minister of Foreign Affairs,first headed the division.New China’s foreign language publishing and distribution efforts began as quickly as anything else.

CRADLE OF PATRIOTISM——Nankai University turns 100 with distinction

Located in the southern part of Tianjin,a municipality neighboring Beijing,Nankai University was founded in August 1919.Over the past 100 years,the university has been a mosaic of China’s history.At the time of its birth,China was struggling under the rule of warlords who were battling for dominance after the fall of the Qing Dynasty(1644-1911),the last imperial dynasty of the country,and was in a fragmented state.Zhang Boling and Yan Xiu,two patriotic educators from Tianjin,had learned about modern educational systems abroad and decided to establish a modern system in their hometown to practice the philosophy of Saving the Nation Through Education.They started with Nankai Middle School in 1912.

On preferred and dispreferred second turns in interaction

Conversation analysis （CA） is an integral part of the study of language in communication, in which preference organization is an important topic for pragmatic research. This paper makes a study of preferred and dispreferred second turns in naturally occurring interactions to show structurally expected or unexpected responses from the second parts of the adjacent pairs. The study is based on the analysis of examples of people＇s actual conversations. It is concluded that in actual conversations, the speaker may make a preferred or dispreferred answer in either marked or unmarked form according to the speaker＇s intention and conversation circumstances.

Twists and Turns of the Post-1949 Years

Success of the revolution represents but only the first step in a long march. ---Mao Zedong Mao Zedong’s announcement in 1949 that "the Chinese people have stoodup," ended the dark decades of domestic fragmentation and foreign subjugation,

The summer solstice is the turning point when light and temperature affect the growth of trees

The interaction between light and temperature is known to influence the seasonal growth of trees.Traditional studies on"light"primarily focus on day length,specifically short day(SD)or long day(LD)conditions.However,little research has been conducted on the process of transitioning between SD and LD conditions.

Predicting Βeta-Turns and Βeta-Turn Types Using a Novel Over-Sampling Approach

β-turn is one of the most important reverse turns because of its role in protein folding. Many computational methods have been studied for predicting β-turns and β-turn types. However, due to the imbalanced dataset, the performance is still inadequate. In this study, we proposed a novel over-sampling technique FOST to deal with the class-imbalance problem. Experimental results on three standard benchmark datasets showed that our method is comparable with state-of-the-art methods. In addition, we applied our algorithm to five benchmark datasets from UCI Machine Learning Repository and achieved significant improvement in G-mean and Sensitivity. It means that our method is also effective for various imbalanced data other than β-turns and β-turn types.