Modeling of microstructure evolution of AZ80 magnesium alloy during hot working process using a unified internal state variable method

In this paper, a unified internal state variable(ISV) model for predicting microstructure evolution during hot working process of AZ80 magnesium alloy was developed. A novel aspect of the proposed model is that the interactive effects of material hardening, recovery and dynamic recrystallization(DRX) on the characteristic deformation behavior were considered by incorporating the evolution laws of viscoplastic flow, dislocation activities, DRX nucleation and boundary migration in a coupled manner. The model parameters were calibrated based on the experimental data analysis and genetic algorithm(GA) based objective optimization. The predicted flow stress, DRX fraction and average grain size match well with experimental results. The proposed model was embedded in the finite element(FE) software DEFORM-3 D via user defined subroutine to simulate the hot compression and equal channel angular extrusion(ECAE) processes. The heterogeneous microstructure distributions at different deformation zones and the dislocation density evolution with competitive deformation mechanisms were captured.This study can provide a theoretical solution for the hot working problems of magnesium alloy.

THE VIRTUAL WORK PRINCIPLE AND LINEAR COMPLEMEN-TARY METHOD FOR COUPLING ANALYSIS OF ELASTO-PLASTIC DAMAGE STRUCTURE

The virtual displacement principle of elasto-plastic damage mechanics is presented. A linear complementary method for elasto-plastic damage problem is proposed by using FEM technique. This method is applicable to solving the damage structure analysis of hardened and softened nonlinear material.

Supercritical carbon dioxide as a new working medium for pneumatic launch:A theoretical study

Compared with the conventionally gaseous or liquid working media,the specific internal energy of supercritical carbon dioxide(SCD)is higher at the same temperature and pressure,and the critical temperature of carbon dioxide is close to room temperature,making SCD a potential new working medium for pneumatic launch.To analyze the feasibility of this conception,an analytical model of a pneumatic catapult is established on basis of the conservations of mass and energy.The model consists of a high-pressure chamber and a low-pressure chamber connected by multiple valves,and there is a movable piston in the low-pressure chamber that can push an aircraft to accelerate.The effects of the launch readiness state of SCD in the high-pressure chamber,the initial volume of the low-pressure chamber and the valve control on the movement of the aircraft are analyzed.It is found that there is a restrictive relation between the temperature and pressure of the launch readiness state of SCD,i.e.,there is a maximum allowable launch readiness pressure when the launch readiness temperature is fixed.If this restrictive relation is not satisfied,the working medium in the low-pressure chamber will drop to its triple point within a few milliseconds,leading to a launch failure.Owing to this restrictive relation,there is an optimal launch readiness state of SCD with the highest working capacity for any allowable launch readiness temperature.The pressure of the low-pressure chamber will decrease significantly as the initial volume increases,leading to a decreased acceleration of the aircraft.The acceleration can be controlled below a critical value by a designed sequential blasting technique of multiple valves.The calculated results show that a 500 kg aircraft can be accelerated from 0 to 58 m/s in 0.9 s with 36 kg of carbon dioxide.This research provides a new technique for the controllable cold launch of an aircraft.

On the Translation of the Government Work Report —Comparing with the State of the Union Address

China's splendid achievements and fast development attract the attention of the whole world. The rising of the great power shock the rest countries. More and more people want to know what is happening in this country and what effect it will bring to the world. At the same time, Chinese people have gradually realized the importance of exchanging information with other countries. Under this motivation, the translation of Chinese materials into English becomes necessary and essential. It is an effective way to present China comprehensively. Among all these materials, Government Work Report is one of the most remarkable ones. The translation of it plays a key role to present the image of China to the world. But, compared with State of the Union address, the translation of Government Work Report contains some problems from the perspective of foreignization and domestication theory. This essay will discuss the differences between these two texts at the lexical, syntactic, and discourse level from the angle of foreignization and domestication theory, and give some suggestions to the translation of Government Work Report.

Work Hard to Ensure Food,Drugs Safety for the People——An interview with Shao Mingli,director-general of the State Food and Drug Administration(SFDA)

Following is an interview given by Shao Mingli, director-general of China＇s State Food and Drug Administration to our reporter on what is being done to ensure food and drug safety in China. As everybody knows, food and drug safety is vital to people＇s lives.

档案工作服务党和国家中心工作的能力提升路径

首先分析了档案工作在服务国家重大战略实施、服务经济社会高质量发展等方面的实践探索,其次剖析了新时代档案工作服务党和国家中心工作能力体系,再次从坚持党的领导、突出主责主业、创新理念方法、强化科技支撑、深化队伍建设、完善治理机制等方面,提出提升档案工作服务党和国家中心工作能力的具体路径。

Fermi level pinning effects at gate–dielectric interfaces influenced by interface state densities

The dependences of Fermi-level pinning on interface state densities for the metal-dielectric, ploycrystalline silicon-dielectric, and metal silicide-dielectric interfaces are investigated by calculating their effective work functions and their pinning factors. The Fermi-level pinning factors and effective work functions of the metal-dielectric interface are observed to be more susceptible to the increasing interface state densities, differing significantly from that of the ploycrystalline silicon-dielectric interface and the metal silicide-dielectric interface. The calculation results indicate that metal silicide gates with high-temperature resistance and low resistivity are a more promising choice for the design of gate materials in metal-oxide semiconductor（MOS） technology.

Third-order polynomial model for analyzing stickup state laminated structure in flexible electronics

Laminated hard-soft integrated structures play a significant role in the fabrication and development of flexible electronics devices. Flexible electronics have advantageous characteristics such as soft and light-weight, can be folded,twisted, flipped inside-out, or be pasted onto other surfaces of arbitrary shapes. In this paper, an analytical model is presented to study the mechanics of laminated hard-soft structures in flexible electronics under a stickup state. Thirdorder polynomials are used to describe the displacement field,and the principle of virtual work is adopted to derive the governing equations and boundary conditions. The normal strain and the shear stress along the thickness direction in the bimaterial region are obtained analytically, which agree well with the results from finite element analysis. The analytical model can be used to analyze stickup state laminated structures, and can serve as a valuable reference for the failure prediction and optimal design of flexible electronics in the future.

ON CRAFT OF SILK “KNITTING” CORDS OF WARRING STATES PERIOD IN JIANGLING

Seven pieces of silk braids excavated from Chu Tomb No.1 at M ashan in Jiangling are thoughtto belong to the knitting fabric.Their structures are double-stitched type,with a lining silk on theback side to fix the knitted threads;besides the traverse linking structure,there are alsomulti-structures by single jersey combined with traverse linking,the excavators declared.The au-thor of this paper believes that those cords can be classified as some intermediary between theknitwear and the needlework.They have the structure similar to certain kinds of knitting,crochetand embroidery,and can be duplicated through two different methods.The differences and similar-ities between these cords and the traditional hand-knitting or embroidery,as well as their originsare discussed.Photographs of the relic and the duplication are presented.

Adapt to New Normal State of Environmental Protection,Fight a Tough Fight,and Make Full Efforts to Build a Beautiful Xi'an

In China, economic growing speed converts from high speed to moderate and high speed; economic structure enters from moderate and low end to moderate and high end; development power converts from investment drive to innovation drive, and investment of resource and environ- ment factors presents declining trend. Spatial pattern of economy development is changing greatly, which needs eco-civilization construction and en- vironmental protection field continuously adjusting focus, environmental rules and laws correspondingly regulating, eco-civilization construction and environmental protection field also entering into new normal state. It requires scientifically understanding, actively adapting to and responding to new normal state of eco-civilization construction and environmental protection,and fighting a tough fight. Firstly, we should handle with the relationship between environment and economy, and strive to explore the way of environmental protection. Secondly, we should insist protection priority and prevention oriented,and promote transformation of environmental management strategy. Finally, we should accelerate to promote eco-civilization system reform and environmental protection management system reform, and further promote environmental protection work in Xi＇an on new level from eight aspects.

Plastic equation of state determined by nano indentation

In order to characterize the plastic state of a deformed material, an indentation method to determine the plastic equation of state(PES) was developed. The work-hardening coefficient and the strain rate sensitivity coefficient of the plastic mechanic equation of state were determined by two kinds of indentation tests respectively. Therefore, the PES of materials under deformation can be obtained, and the plastic state of materials can be determined.

Determination of plastic equation of state by indentation method on 304 stainless steel

An indentation method for determining the plastic mechanical equation of state (PES) was studied. The constant loading rate and constant loading rate/load indentation tests were carried out. The method for determining the work-hardening coefficient and the strain rate sensitivity coefficient of PES were discussed in detail. 304 stainless steel hot-treated at 1100°C was used to verify the method. The work-hardening coefficient and strain rate sensitivity coefficient of 304 stainless steel were respectively determined as 0.30 and 0.015. These values are very close to those achieved by tensile tests. From the establishment of the PES of 304 stainless steel it is shown that the PES obtained by the indentation method is easier than that by the tensile test.

The Influence of Sampling Site on Blood Lactate Response to Steady State Exercise

In sports sciences, blood lactate is commonly measured for performance testing or setting exercise intensity. Differences in measuring lactate concentration over time and across sampling sites during constant exercise are unknown. We aimed to compare blood lactate concentration across sampling sites during constant exercise. Eight participants performed three bouts of 20-min steady-state cycle exercise, consisting of 45, 60, and 75% of peak oxygen uptake (V . O2peak). Blood lactate levels were measured simultaneously from the fingertip and earlobe every 5 min during exercise. The time course analysis revealed that lactate level in the fingertip was significantly higher than in the earlobe at either work intensity (P < 0.05). A significant interaction effect (site x time) was observed at 60% V O2peak (P < 0.001), which indicated that the difference in samples across sampling sites decreased over time. The levels in the fingertip samples were higher at 5 min (P < 0.05);this difference was not noted after 10 min. Similarly, the fingertip values were significantly higher until 10 min (P < 0.05), but not after 15 min at 75% V O2peak. These findings suggest that the sampling site may affect the time course of change in lactate value under a constant workload.

党建工作对国有企业财务绩效的影响研究——以燕塘乳业公司为例

党建工作在中国国有企业中扮演着至关重要的角色,作为国有企业治理的重要组成部分,党建工作对企业的发展和财务绩效有着深远的影响。燕塘乳业公司作为国有企业的代表之一,其发展历程和经验值得深入研究。本研究将从党建工作的角度出发,以燕塘乳业公司为观测对象,选取2011年至2023年燕塘乳业公司的季度数据作为研究样本,采用线性回归方法探讨党建对国有企业财务绩效的影响机制。研究发现,党建工作在企业运作与发展中对财务绩效具有显著的正向影响,即党建工作的力度得到进一步加强,党建功能得以显著发挥,并与企业的运营活动紧密融合时,公司的财务绩效将实现更为显著的增长。

国家社会工作的理念、内涵与发展策略

中国社会工作发展离不开国家力量的驱动,是一种国家社会工作。它与治疗性社会工作不同,主要以马克思主义为指导,隶属于国家治理体系,融合行政性、人民性、专业性和本土性于一体,即使是微观的社会服务背后也蕴含着强大的“国家在场”。中国社会工作还具有问题寻解性、介入整体性、民众需求生活性及专业感知被动性等特点。因此,发展国家社会工作的策略有:沿循结构性社会工作的脉络,跳出社会工作“治疗术”的狭窄通道和私领域服务,回归社会工作的公共性,从整体上改进和提升民生福祉;夯实国家社会工作的内涵,构建中国社会工作自主知识体系;打造国家社会工作的科学方法体系,在其各个层面吸纳并融合专业社会工作方法,实现本土性和专业性的相互嵌合。

基于Yolopose的挖掘机检测与工作状态识别

针对光缆、高压油气管道等地下基础设施周边容易受到挖掘机的野蛮入侵问题.本文提出了一种结合Yolopose和多层感知机的挖掘机检测与工作状态判别方法.首先,设计了基于Yolopose的挖掘机6点姿势的提取网络Yolopose-ex;其次,利用Yolopose-ex模型提取视频中挖掘机工作姿态的变化信息,构建了挖掘机的工作状态特征向量(MSV);最后,利用深度学习算法多层感知机(multilayer perceptron,MLP)分析了视频中的挖掘机的工作状态.实验结果表明,所提出的方法克服了复杂背景难以识别的问题,对挖掘机工作状态识别准确率达到了96.6%,具有较高的推理速度和泛化能力.

数字化进程中美国情报工作演进趋势

[研究目的]数字技术的迭代升级能促进情报工作的优化发展。美国作为全球情报体系最健全、情报模式最先进的国家,研究其数字化进程中情报工作演进趋势,不仅能正确认识情报工作与数字技术发展的关系,也有助于更好地应对新形势下美国对华情报渗透。[研究方法]针对美国情报工作的主要目标、关注对象、重点任务、体系建设四个关键变量,运用文献研究、历史研究、归纳分析等方法,以信息化、网络化、智能化三个数字技术发展阶段为主线,对美国情报工作演进趋势展开进程分析。[研究结论]美国情报工作在数字技术迭代升级进程中呈现出以下演进趋势:主要目标从助力美苏竞争调整为战后国际秩序重塑、地缘政治紧张对抗;关注领域从传统安全领域扩展到非传统安全领域、重要领域的全球领先地位;重点任务从聚焦美苏全面竞争变化为应对新安全威胁、数字技术赋能优化;体系建设呈现出现代化、一体化和数字化的演进趋势。

管制员不良工作状态与疲劳状态分析

为分析管制员不良的工作状态与疲劳状态之间的关系,监测管制员工作状态,采用主观评价方法收集185名管制员的主观看法,通过灰色关联分析不良工作状态和疲劳状态的影响因素,对其重要性进行排序,并通过疲劳自评量表研究了管制员处于不良工作状态时对应的疲劳程度。结果表明,管制员不良工作状态与疲劳状态影响因素之间存在差异性和统一性,且当管制员处于中度疲劳后,其工作状态将受到影响,因此,对管制员疲劳状态的研究应当更多关注于中度及重度疲劳的识别。

正确理解按劳分配 合理调节收入分配

按劳分配曾经因为是“资产阶级法权”而被贬低,后来又作为纯而又纯的社会主义分配形式而被抬高。按劳分配实际上表明的是“一分耕耘,一分收获”的客观规律,只是在存在剥削的社会里,劳动成果被不同的剥削阶级所掠夺,劳动者只能得到其中一小部分。按劳分配不是“不折不扣的劳动所得”,要注意与级差地租区别开来,与利润平均化区别开来,与妨碍利润平均化的垄断收入区别开来。要合理调节收入分配,首先要合理地或充分地占有收入。要严禁企业拖欠工资,严禁超出法律规定的工作时间长度,规范财政转移,调节级差收入,调整国有企业布局,实行第三次分配信息互通共享。