走向学生自主管理——“弱化”班主任在班级管理中作用的探究

随着时代的发展,素质教育已经普遍实行,基于这一背景,班主任在落实班级管理时,需要高度重视学生的主体地位和参与程度,并且明确自身作为班级发展引领者的角色。班主任要做到主动“放手”,使学生能够拥有更多自主管理机会,从而不断提升学生的自主管理和约束能力,同时改善班级管理效果。基于此,文章主要对“弱化”班主任在班级管理中的作用展开分析,具体探讨其对强化学生自主管理能力的重要意义以及具体策略。

从“弱化”到“催化”:新生代农民工家庭与婚配悖论研究

本文以来自安徽、河南两省并在南京、武汉、宁波等地打工的二十余名青年农民工为典型个案,通过以对其持续一年多的深度访谈和生活变化为一手资料,探究流动农民的生活轨迹与生存规律。文章指出,成长中家庭功能的"弱化"与成年后婚配模式的"催化"成为新生代农民工无法超越的历史命运,从"弱化"到"催化"的快速转型不仅在理论上隐藏着社会化断裂、角色冲突失败等悖论与矛盾,也造成客观现实中的适应障碍、认同困境乃至家庭解组等后果,这在增加青年农民工个体社会化挫折的同时,亦加剧社会风险与管理成本,在相当一段历史时期内成为城市化与现代转型进程中的顽疾。

青年民工家庭“弱化”与婚育“催化”研究

时至今日,频繁持续的流动已经成为青年民工的生存常态,然而成家与立业的传统使命,即青年社会化的主要内容不仅没有改变、削弱,反而愈加强化甚至提前,进而在从"弱化"到"催化"的悖论过程中急剧完成。典型个案研究显示,成长中家庭功能的"弱化"与成年后婚育模式的"催化"成为青年民工无法超越的历史命运,而从"弱化"到"催化"的快速转型不仅在理论上隐藏着社会化断裂、角色冲突失败等悖论,也造成客观现实中的适应障碍、认同困境乃至家庭解组等后果,这在增加其个体社会化挫折的同时,也加剧了社会风险与管理成本,在相当一段时期内成为城市化与现代转型进程中的顽疾。

“弱化”的思想在结构优化设计中的应用

通过几个实际工程例子,指出结构优化设计,可以从结构整体出发,弱化整体结构刚度,降低结构的地震反应;可以从构件间的连接出发,减去不必要的约束;可以从一个构件出发,使杆件的形式与受力特点相一致;可以从一个节点出发,使其变得更加简单可靠。"弱化"的思想,是从繁杂的结构特性中梳理出少量甚至单个的、过强的结构特性,利用同步失效准则或满应力准则,使整体结构和各构件的承载能力极限状态、正常使用极限状态接近且不小于规范的要求,以达到节约材料、便于建造和结构美观合理的目的。

“弱化”班主任作用,提升初中生自我管理能力

:初中生正好处在关键的成长期,作为班主任就要致力于正确引导学生,确保运用科学方式来培育初中生的自我管理与自我约束能力。要达到初中生自我管理能力的目标,需要做到适当“弱化”班主任的作用,通过锻炼学生管理自身各种日常事务的能力。

应用“弱化”思想解题例谈

波利亚曾说过：“解数学题必须要站在思想方法的高度来统揽全题，且在适当的时机下要能创造性的思考问题，”显然，思想方法对解题有着非常重要的作用，初中阶段要我们掌握的思想方法很多，如：整体思想、分类思想、方程思想、数形结合思想等等。

Influencing factors analysis of hard limestone reformation and strength weakening under acidic effect

Roof disaster has always been an important factor restricting coal mine safety production.Acidic effect can reform the rock mass structure to weaken the macroscopic strength characteristics,which is an effective way to control the hard limestone roof.In this study,the effects of various factors on the reaction characteristics and mechanical properties of limestone were analyzed.The results show that the acid with stronger hydrogen production capacity after ionization(pK_(a)<0)has more prominent damage to the mineral grains of limestone.When pKa increases from−8.00 to 15.70,uniaxial compressive strength and elastic modulus of limestone increase by 117.22%and 75.98%.The influence of acid concentration is manifested in the dissolution behavior of mineral crystals,the crystal defects caused by large-scale acid action will lead to the deterioration of limestone strength,and the strength after 15%concentration reformation can be reduced by 59.42%.The effect of acidification time on limestone has stages and is the most obvious in the initial metathesis reaction stage(within 60 min).The key to the strength damage of acidified limestone is the participation of hydrogen ions in the reaction system.Based on the analytic hierarchy process method,the influence weights of acid type,acid concentration and acidification time on strength are 24.30%,59.54% and 16.16%,respectively.The research results provide theoretical support for the acidification control of hard limestone roofs in coal mines.

Effect of calcium addition on microstructure and texture modification of Mg rolled sheets

The mechanical properties and texture of AM60（Mg-6.0Al-0.3Mn,mass fraction %） and ZXM200（Mg-1.6Zn-0.5Ca-0.2Mn） Mg alloys subjected to multi-pass hot rolling were investigated.The finer recrystallized grains usually exhibit particular preferred orientations and then alter the total texture feature of rolled sheets.Ca solid solution into Mg matrix serves to the formation of texture component with c-axis rotated away from normal direction towards transverse direction and then weakens the overall texture intensity,resulting in a similar anisotropic characteristic to RE-containing Mg alloys.

Determination the Vigor of Rice Seed with Different Degrees of Aging with Ultraweak Chemiluminescence During Early Imbibition

用高灵敏度的单光子计数系统探测人工老化 (40℃ ,相对湿度 90 % ) 0、7、14和 2 1d的水稻种子吸胀初期的超弱化学发光强度变化 ,首次观测到水稻 (OryzasativaL .)种子吸胀初期超弱化学发光强度与其老化程度有关。加水激活水稻种子的超弱化学发光 ,其强度依赖于种子的老化程度。实验结果表明水稻种子的人工老化时间越短 ,则吸胀初期 (2 0～ 30min)超弱化学发光的强度越强 ,萌发率越高。水稻种子萌发率与超弱化学发光强度呈显著正相关。观测水稻种子吸胀初期超弱化学发光强度的变化可望成为检测种子老化程度的一种快速、简便、无损伤的新方法。

Effect of Weak Noise on the Frequency Tuning of Mouse Inferior Collicular Neurons

In order to study the effect of weak noise on the sound signal extraction of mouse (Mus musculus Km) inferior collicular (IC) neurons from environments,we examined the changes in frequency tuning curves (FTCs) of 32 neurons induced by a weak noise relative to 5 dB below minimum threshold of tone (reMT-5 dB) under free field stimulation conditions.The results were as follows:① There were three types of variations in FTCs,sharpened (34.4%),broadened (18.8%),and unaffected (46.9%),nevertheless,only the alteration of sharpened FTCs was statistically different.② Sharpness of frequency tuning induced by a reMT-5 dB noise was very strong.Q 10 and Q 30 of FTCs were increased by (34.42±17.04)% (P=0.026,n=11) and (46.34±22.88)% (P=0.009,n=7).③ The changes of inverse-slopes (ISs,kHz/dB) between high (IS high) and low (IS low) limbs of FTCs were dissymmetry.The IS high of FTCs decreased markedly (P=0.046,n=7),however,there was little change (P=0.947,n=7) in IS low.Our data revealed for the first time that the weak noise could sharpen frequency tuning and increase the sensitivity on the high frequency of sound signal in IC neurons of mouse.

Research Progress of Vulnerability Assessment on Grassland Ecosystem under Climate Change

[Objective] The aim was to review on vulnerability evaluation of grassland ecosystem under climate change.[Method] In the research,vulnerability evaluation methods of ecosystem under climate changes,at home and abroad,and the related cases and research progress in China were reviewed.In addition,the future of evaluation research was predicted.[Result] Ecosystem vulnerability to climate change is an important part of climate change research.It is necessary and urgent to improve evaluation methods and reduce uncertainty of future vulnerability evaluation to make evaluation more comprehensive and objective.Furthermore,evaluation on effects of human activity on natural ecosystem vulnerability should be highlighted.[Conclusion] The research provided reference for establishment of a new management model for ecosystem adaptability to climate and sustainable development of grasslands in northern China.

从“洛克条件”到“诺齐克条件”

本文拟从诺齐克"持有正义"论的基点"获取正义"出发来分析诺齐克财产权起源学说的逻辑证明过程,指出诺齐克是通过弱化"洛克条件",并将其转换为"诺齐克条件"这样一个"弱化-构建"过程来完成理论推导的。诺齐克严密而智慧的论证极富启迪意义;但在劳动确立财产权问题、"自然状态"下外界资源所有权性质的设定问题、以及诺齐克条件赖以成立的"基准状态"问题等重要环节上尚有明显漏洞。

Effect of Weak Light on the Peroxidation of Membrane_Lipid of Cherry Leaves

The effect of weak light on the peroxidation of membrane_lipid of one_year_old cherries ( Prunus pseudocerasus L. 'Laiyang') was studied by whole_tree shading. The results showed that the net photosynthetic rate of cherry leaves under weak light was remarkably lower; the activity peroxidase (POD) increased when light intensity decreased; the activity of catalase (CAT) showed an opposite trend, and it was positively correlated with light intensity; the activity of superoxide dismutase (SOD) increased under 366 μmol·m -2 ·s -1 and 533.8 μmol·m -2 ·s -1 light intensity, but decreased under 228.8 μmol·m -2 ·s -1 and 83.9 μmol·m -2 ·s -1 light intensity. A remarkable increase of malondialdehyde (MDA), a product of membrane_lipid peroxidation, was also observed in cherry leaves when treated with weak light, indicating more serious peroxidation in the membrane.

Anti-interference beam pattern design based on second-order cone programming optimization

When signal-to-interference ratio is low, the energy of strong interference leaked from the side lobe of beam pattern will infect the detection of weak target. Therefore, the beam pattern needs to be optimized. The existing Dolph-Chebyshev weighting method can get the lowest side lobe level under given main lobe width, but for the other non-uniform circular array and nonlinear array, the low side lobe pattern needs to be designed specially. The second order cone programming optimization （SOCP） algorithm proposed in the paper transforms the optimization of the beam pattern into a standard convex optimization problem. Thus there is a paradigm to follow for any array formation, which not only achieves the purpose of Dolph-Chebyshev weighting, but also solves the problem of the increased side lobe when the signal is at end fire direction The simulation proves that the SOCP algorithm can detect the weak target better than the conventional beam forming.

Exploration of weakening mechanism of uniaxial compressive strength of deep sandstone under microwave irradiation

Traditional mechanical rock breaking method is labor-intensive and low-efficient,which restrictes the development of deep resources and deep space.As a new rock-breakage technology,microwave irradiation is expected to overcome these problems.This study examines the failure characteristics,weakening law,and breakdown mechanism of deep sandstone(depth=1050 m)samples in a microwave field.The macroscopic and microscopic properties were determined via mechanical tests,mesoscopic tests,and numerical simulations.Microwave application at 1000 W for 60 s reduced the uniaxial compressive strength of the sandstone by 50%.Thermal stress of the sandstone was enhanced by uneven expansion of minerals at the microscale.Moreover,the melting of some minerals in the high-temperature environment changed the pore structure,sharply reducing the macroscopic strength.The temperature remained high in the lower midsection of the sample,and the stress was concentrated at the bottom of the sample and along its axis.These results are expected to improve the efficiency of deep rock breaking,provide theoretical and technical support for similar rock-breakage projects,and accelerate advances in deep-Earth science.

Brazilian disc test study on tensile strength-weakening effect of high pre-loaded red sandstone under dynamic disturbance

Tensile failure(spalling or slabbing)often occurs on the sidewall of deep tunnel,which is closely related to the coupled stress state of deep rock mass under high pre-static load and dynamic disturbance.To reveal the mechanism of rock tensile failure caused by this coupled stress mode,the Brazilian disc tests were carried on red sandstone under high pre-static load induced by dynamic disturbance.Based on the pure static tensile fracture load of red sandstone specimen,two static load levels(80%and 90%of the pure static tensile fracture load)were selected as the initial high pre-static loading state,and then the dynamic disturbance load was applied until the rock specimen was destroyed.The dynamic disturbance loading mode adopted a sinusoidal wave(sine-wave)load,and the loading wave amplitude was 20%and 10%of the pure static tensile fracture load,respectively.The dynamic disturbance frequencies were set to 1,10,20,30,40,and 50 Hz.The results show that the tensile failure strength and peak displacement of red sandstone specimens under coupled load actions are lower than those under pure static tensile load,and both parameters decrease significantly with the increase of dynamic disturbance frequency.With the increase of dynamic disturbance frequency,the decrease range of tensile strength of red sandstone increased from 3.3%to 9.4%when the pre-static load level is 80%.While when the pre-static load level is 90%,the decrease range will increase from 7.4%to 11.6%.This weakening effect of tensile strength shows that the deep surrounding rock is more likely to fail under the coupled load actions of pre-static load and dynamic disturbance.In this tensile failure mechanism of the deep surrounding rock,the stress environment of deep sidewall rock determines that the failure mode of rock is a tensile failure,the pre-static load level dominates the tensile failure strength of surrounding rock,and dynamic disturbance promotes the strength-weakening effect and affects the weakening range.

Dynamic characteristics of high stressed red sandstone subjected to unloading and impact loads

In the process of deep projects excavation,deep rock often experiences a full stress process from high stress to unloading and then to impact disturbance failure.To study the dynamic characteristics of three-dimensional high stressed red sandstone subjected to unloading and impact loads,impact compression tests were conducted on red sandstone under confining pressure unloading conditions using a modified split Hopkinson pressure bar.Impact disturbance tests of uniaxial pre-stressed rock were also conducted(without considering confining pressure unloading effect).The results demonstrate that the impact compression strength of red sandstone shows an obvious strain rate effect.With an approximately equal strain rate,the dynamic strength of red sandstone under confining unloading conditions is less than that in the uniaxial pre-stressed impact compression test.Confining pressure unloading produces a strength-weakening effect,and the dynamic strength weakening factor(DSWF)is also defined.The results also indicate that the strain rate of the rock and the incident energy change in a logarithmic relation.With similar incident energies,unloading results in a higher strain rate in pre-stressed rock.According to the experimental analysis,unloading does not affect the failure mode,but reduces the dynamic strength of pre-stressed rock.The influence of confining pressure unloading on the shear strength parameters(cohesion and friction angle)is discussed.Under the same external energy impact compression,prestressed rock subjected to unloading is more likely to be destroyed.Thus,the effect of unloading on the rock mechanical characteristics should be considered in deep rock project excavation design.

Wave field forward modeling and theoretical analysis of weakness in discrete media

The elasticity, viscosity, and the relationships derived from rheology weakness properties are taken into account in mechanics. Comparing with the corresponding relationships derived from damage mechanics, we find the weakness factor has the same significance as the damage factor. We simulate the wave field using a staggered-grid pseudospectral method to show the influence of the weakness factor qualitatively. Applying the analytical solution of plane waves, we give the velocity and attenuation coefficient of three body waves, which are affected by the wave frequency and the weakness factor of saturated discrete media. Our results show that velocity decreases with increasing weakness factor, the attenuation coefficient increases with an increase in the weakness factor, and that the influence of weakness depends on the mode of the body waves.

Strength weakening effect of high static pre-stressed granite subjected to low-frequency dynamic disturbance under uniaxial compression

This study aimed to elucidate the strength weakening effect of high static pre-stressed rocks subjected to low-frequency disturbances under uniaxial compression.Based on the uniaxial compressive strength(UCS)of granite under static loading,70%,80%,and 90%of UCS were selected as the initial high static pre-stress(σ_(p)),and then the pre-stressed rock specimens were disturbed by sinusoidal stress with amplitudes of 30%,20%,and 10%of UCS under low-frequency frequencies(f)of 1,2,5,and 10 Hz,respectively.The results show that the rockburst failure of pre-stressed granite is caused by low-frequency disturbance,and the failure strength is much lower than UCS.When theσp or f is constant,the specimen strength gradually decreases as the f or σ_(p) increases.The experimental study illustrates the influence mechanism of the strength weakening effect of high static pre-stress rocks under low-frequency dynamic disturbance,that is,high static pre-stress is the premise and leading factor of rock strength weakening,while low-frequency dynamic disturbance induces rock failure and affects the strength weakening degree.

Frailty is independently associated with increased hospitalisation days in patients on the liver transplant waitlist

AIMTo investigate the impact of physical frailty on risk of hospitalisation in cirrhotic patients on the liver transplant waitlist.METHODSCirrhotics listed for liver transplantation at a single centre underwent frailty assessments using the Fried Frailty Index, consisting of grip strength, gait speed, exhaustion, weight loss, and physical activity. Clinical and biochemical data including MELD score as collected at the time of assessment. The primary outcome was number of hospitalised days per year; secondary outcomes included incidence of infection. Univariable and multivariable analysis was performed using negative binomial regression to associate baseline parameters including frailty with clinical outcomes and estimated incidence rate ratios (IRR).RESULTSOf 587 cirrhotics, 64% were male, median age (interquartile range) was 60 (53-64) years and MELD score was 15 (12-18). Median Fried Frailty Index was 2 (1-3); 31.6% were classified as frail (fried frailty &#x02265; 3). During 12 mo of follow-up, 43% required at least 1 hospitalisation; 38% of which involved major infection. 107/184 (58%) frail and 142/399 (36%) non-frail patients were hospitalised at least once (P &#x0003c; 0.001). In univariable analysis, Fried Frailty Index was associated with total hospitalisation days per year (IRR = 1.51, 95%CI: 1.28-1.77; P &#x02264; 0.001), which remained significant on multivariable analysis after adjustment for MELD, albumin, and gender (IRR for frailty of 1.21, 95%CI: 1.02-1.44; P = 0.03). Incidence of infection was not influenced by frailty.CONCLUSIONIn cirrhotics on the liver transplant waitlist, physical frailty is a significant predictor of hospitalisation and total hospitalised days per year, independent of liver disease severity.