Effect of flow stress—strain relation on forming limit of 5754O aluminum alloy

A modified Swift type flow stress—strain relation was presented in order to describe the uniaxial tension test curve reasonably. The FLD-strain （forming limit diagram made up of limit strain） of 5754O aluminum alloy sheet was calculated based on the two flow stress—strain relations using Yld2000-2d yield function. By comparing the theoretical and experimental results, it is found that the calculated FLD-strain based on the modified Swift flow stress—strain relation can reasonably describe the experimental results. However, though the common Voce flow stress—strain relation can describe the deformation behavior during homogenous deformation phase accurately, the FLD-strain calculated based on it is obviously lower than the experimental result. It is concluded that the higher the hardening rate of sheet metal is, the higher the forming limit is. A method for determining the reasonable flow stress—strain relation is recommended for describing the material behavior during inhomogenous phase and the forming limit of sheet metal.

Determination of Relationships and Al ocation of Responsibilities——Taking the Adjudication of Household Service Contract Disputes as an Example

The combination of the realistic demand of urban families to raise children and provide for the aged and the employment demand of rural migrant workers will inevitably lead to the continuous growth of the market demand for household care services.The determination of the tripartite legal relationship between household workers,household service agencies,and families(individuals)is an important issue for the normative development of the household service industry.In specific judicial practice,local courts perform differently in the determination of the relationship between“household workers and household service agencies.”The application of law in relevant cases also often swings between the civil law and the labor law.The Civil Code of the People’s Republic of China(hereinafter“the Civil Code”)does not retain the concept of“employment relationship”used in the original Interpretation of the Supreme People’s Court on Several Issues Concerning the Application of Law in the Trial of Personal Injury Compensation Cases.Then,what is the relationship between household workers,household service agencies,and families(individuals)after the Civil Code came into force?This article shows the judicial dilemma currently faced by the household workers in the protection of labor rights and interests through an empirical analysis of the victim liability disputes of household workers and puts forward countermeasures and suggestions for improving the occupational injury protection mechanism of household workers in China through a comparative study of the occupational injury risk sharing mechanism of household workers and an analysis of the local exploration of the occupational injury protection system of flexible employees in China.

What Is the Role of Work-Related Factors in Self-Reported Health Inequalities among Employed Individuals? A Longitudinal Study in Luxembourg

Objectives: We measured health inequalities among employed Luxembourg residents over time and the socio-economic and work-related determinants. Design and Setting: Longitudinal data were obtained from the Socio-economic Liewen zu Lëtzebuerg/European Union Survey on Income and Living Conditions, which has been conducted each year since 2003 in Luxembourg. Participants: Participants comprised 727 Luxembourg residents (58% men), aged between 21 and 55 years in 2003, who were employed between 2003 and 2012. Primary and Secondary Outcomes Measured: The variable of interest was self-reported health. We used transition indicators on work-related factors to consider changes that individuals may have experienced in their job over this period. Results: People who moved from a part-time to a full-time contract (odds ratio (OR): 5.52, confidence interval (CI): 1.55 - 19.73), and those who moved from the 3rd or 4th quartile of earnings to the 1st or 2nd quartile (OR: 2.48, CI: 1.02 - 6.05) between 2003 and 2012, had a higher risk of being in poor health in 2012. The risk of deterioration in self-reported health in 2012 among people who were healthy in 2003 was associated with the type of contract, economic activity, and occupation. Conclusion: Health inequalities occur among employed people in Luxembourg. Their importance varies according to work-related characteristics and economic activity. Our findings showed that declined health status was associated with contract type, profession, and economic activity. This suggests that measures should be taken to maintain good health for people working in these specific occupations or economic sectors (e.g. preventive action, reduction of risk exposure, change of occupation in the same company, and so on).

PRRT2基因突变相关疾病谱的临床特征及遗传学分析

目的回顾性分析总结10例PRRT2基因突变相关疾病谱患者的临床特点及遗传学特征。方法收集2020-07—2022-08就诊于首都医科大学宣武医院儿科的10例PRRT2基因相关癫痫患儿的临床特征、脑电图、头颅磁共振检查、基因特征及治疗结果,回顾性分析其特征。结果10例患儿均提示PRRT2基因杂合突变,其中3例为片段缺失,5例为移码突变,1例为剪接突变。10例患者中男5例,女5例,起病年龄4个月~10岁,其中7例诊断为自限性家族性婴儿癫痫(SFIE),1例诊断为发作性运动诱发性运动障碍(PKD),2例诊断为伴婴儿惊厥的发作性运动诱发性运动障碍(IC/PKD);5例存在PRRT2基因突变相关疾病家族史。7例口服奥卡西平治疗后发作控制,3例口服左乙拉西坦治疗后发作控制。结论PKD、SFIE及IC/PKD是一组与PRRT2基因突变相关的疾病谱,c.649dupC基因突变位点是热点突变位点。对于高度考虑SFIE、PKD及IC/PKD的患者,如全外显子测序未发现异常基因,需进一步行内含子及染色体微缺失/微重复检测,达到早期诊断及治疗的目的。

Predictors of visual outcome in eyes with choroidal neovascularization secondary to age related macular degeneration treated with intravitreal bevacizumab monotherapy

AIM:To evaluate the predictors of visual improvement in eyes with naive choroidal neovascularization secondary to age-related macular degeneration (CNV -AMD) treated with intravitreal bevacizumab (IVB) monotherapy. METHODS:Fifty eyes with naive CNV-AMD with pretreatment best-corrected visual acuity (BCVA) better than 20/200 and treated with IVB monotherapy were evaluated. Several variables including age, sex, pre-treatment BCVA, CNV type and lesion size on fluorescein angiogram as well as SD-OCT parameters including pre-treatment central macular thickness (CMT), inner-segment/outer-segment (IS/OS) junction integrity, and external limiting membrane (ELM) integrity were analyzed to predict visual outcome.RESULTS:On univariate regression, pretreatment ELM damage was associated with less visual improvement after treatment (P =0.0145). However, ELM damage predicted only 10% of the visual outcome. On multivariate regression, pretreatment BCVA, IS/OS junction, and ELM integrity on SD-OCT were the significant predictors for the treatment effect and together predicted 37% of visual improvement. CONCLUSION:Pretreatment BCVA, ELM and IS/OS junction integrity on SD-OCT are of significant value inpredicting the visual improvement in naive wet AMD patients treated with IVB monotherapy.

Soil Atterberg Limits and Consistency Indices as Influenced by Land Use and Slope Position in Western Iran

Atterberg limits and consistency indices are used for classifications of cohesive(fine-grained) soils in relation with compaction and tillage practices. They also provide information for interpreting several soil mechanical and physical properties such as shear strength, compressibility, shrinkage and swelling potentials. Although, several studies have been conducted regarding the land use effects on various soil mechanical properties, little is known about the effects of land use and slope positions on Atterberg limits and consistency indices. This study was conducted to investigate the effects of land use and slope position on selected soil physical and chemical properties, Atterberg limits and consistency indices in hilly region of western Iran. Three land uses including dryland farming, irrigated farming and pasture and four slope positions(i.e., shoulder, backslope, footslope, and toeslope) were used for soil samplings. One hundred eleven soil samples were collected from the surface soil(0-10 cm). Selected physical and chemical properties, liquid limit(LL), plastic limit(PL) and shrinkage limit(SL) were measured using the standard methods; and consistency indices including plastic index(PI), friability index(FI), shrinkage index(SI) and soil activity(A=PI/clay) were calculated. The results showed that irrigated farming significantly increased organic matter content(OM) and OM/clay ratio, and decreased bulk density(ρb) and relative bulk density(ρb-rel) as a result of higher biomass production and plant residues added to the soil compared to other land uses. Except for sand content, OM, ρb, cation exchange capacity(CEC) and calcium carbonate equivalent(CCE), slope position significantly affected soil physical and chemical properties. The highest values of silt, OM/clay and CEC/clay were found in the toeslope position, predominantly induced by soil redistribution within the landscape. The use of complexed(COC)- noncomplexed organic carbon(NCOC) concept indicated that majority of the studied soils were located below the saturation line and the OM in the soils was mainly in the COC form. The LL, PI, FI and A showed significant differences among the land uses; the highest values belonged to the irrigated farming due to high biomass production and plant residues returned to the soils. Furthermore, slope position significantly affected the Atterberg limits and consistency indices except for SL. The highest values of LL, PI, SI and A were observed in the toeslope position probably because of higher OM and CEC/clay due to greater amount of expandable phyllosilicate clays. Overall, soils on the toeslope under irrigated farming with high LL and SI and low values of FI need careful tillage management to avoid soil compaction.

Thermodynamic limit of the XXZ central spin model with an arbitrary central magnetic field

The U(1)symmetry of the X X Z central spin model with an arbitrary central magnetic field B is broken,since its total spin in the z-direction is not conserved.We obtain the exact solutions of the system by using the off-diagonal Bethe ansatz method.The thermodynamic limit is investigated based on the solutions.We find that the contribution of the inhomogeneous term in the associated T-Q relation to the ground state energy satisfies an N^(-1)scaling law,where N is the total number of spins.This result makes it possible to investigate the properties of the system in the thermodynamic limit.By assuming the structural form of the Bethe roots in the thermodynamic limit,we obtain the contribution of the direction of B to the ground state energy.It is shown that the contribution of the direction of the central magnetic field is a finite value in the thermodynamic limit.This is the phenomenon caused by the U(1)symmetry breaking of the system.

On the Elementary Mechanical Effects of the Space-Time-Symmetry Relativity

This paper is an addendum to the article “On the Evolution of Approaches to the Space- Time Symmetry”, Natural Science, Vol. 10, No. 3, pp. 81-84, 2018. The analysis is based on the Galileo’s postulate that all inertial reference frames are equal. The postulate results immediately in the absolute speed limit, which is identical for all bodies in all reference frames. Two kinds of elementary particles are admitted: unhurried and restless ones (ex-emplified, accordingly, with electrons and photons). Any particle may be treated as wave packet, the particle mass and momentum depending on the reference frame. Thus, space-time-sym- metry is the natural background for the relativistic and quantum theo-ries.

国内外新就业形态劳动者权益保障研究脉络与热点追踪--基于CiteSpace的文献计量分析

党的二十大报告强调,“要加强灵活就业和新就业形态劳动者权益保障”。围绕这一主题,借助CiteSpace等文献分析工具,聚焦发文量、文献被引频次、期刊影响因子、核心作者群、关键词聚类等指标,对近年来国内外关于新就业形态劳动者权益保障的主题文献进行计量分析,系统梳理其研究脉络,得出了如下结论和研究展望:近十年来,国内外对新就业形态劳动者权益保障的研究逐步深入,但文献总量较少,核心作者群相对分散,业内学术影响力不高,未来研究方向将集中在新就业形态劳动者新型雇佣关系认定和劳动权益保障两个方面,并致力于在工会职能创新、立法创新、社会保险政策实践创新3个方面作出实质性突破。

新业态从业者劳动权益保障的困境与出路

新业态从业者不同于传统劳动者,其在所处行业、组织方式、用工方式、计酬方式等方面表现出“新”的独特性的同时,该类人员劳动权益无法得到有效保障的现状也对传统劳动关系理论提出了新的挑战。通过对新业态从业者劳动权益保护现状进行研究,从现行保险制度、传统劳动关系的认定标准、诉讼与仲裁的衔接、劳动者维权力量等方面分析保障不足的内在原因,进而从加强保险制度的建设、更新劳动关系认定标准、增强维权力量、协同治理等方面提出完善劳动者权益保障的建议,以规范新型用工关系,促进劳动力市场有序发展,推动数字经济时代和谐劳动关系的构建。

不完全劳动关系法律属性及制度构建探究

梳理学界及相关政策文件对不完全劳动关系的定义与解释,将劳动从属性与新就业形态劳动者特征以及外包用工模式相结合,总结出不完全劳动关系的本质是新就业形态下特有的具备弱人格从属性、经济从属性、组织从属性的新型用工关系。当前,该领域研究存在两大问题:一是不完全劳动关系的法律属性及地位不清晰;二是不完全劳动关系的制度构建方案不明确。参考“类雇员”制度及多要素权衡规则,在劳动三分体系基础之上提出三项建议:一是将不完全劳动关系纳入未来《劳动法典》中专门规制;二是引入考察要素制定不完全劳动关系认定标准;三是将不完全劳动关系劳动者权利划分为基础权利和特有权利。

涉农高职院校劳动精神融入就业教育的路径研究

劳动精神蕴含着丰富的育人元素和综合育人价值,将劳动精神涵养教育与大学生就业指导工作相结合,既符合学生成长规律,又顺应新时代劳动就业的新形势和新要求。该文在阐释劳动精神与就业教育本质契合的基础上,探讨劳动精神涵养教育在涉农高职院校就业指导工作中的意义,根据涉农高职院校学段特点,构建劳动精神涵养教育融入就业教育具体路径,通过晓之以理,动之以情,锻炼意志,培养行为,以期切实提高大学生高质量就业的能力。

新就业形态劳动者养老保险的团体型参缴机制研究

在现行社会养老保险的二元参缴机制中,针对“非完全符合确立劳动关系情形”的劳动者而言,适用单位型参缴机制难以界定参缴义务主体,适用个人型参缴机制存在个人缴费负担过重的问题。德国类雇员经济从属性特质推演出“经济依赖标准”及其“社会保护必要性”的理论,作为拟制新就业形态劳动者与平台企业构成团体型风险共同体的法理依据,以及日本厚生年金保险法上被保险人资格的独立判断标准,推演出适格用工主体作为风险共同体参缴义务人的正当性基础,为确立平台企业在团体型风险共同体中的法律地位提供了理论支持。基于强制参缴的目的保障功能,应坚持行政确认说作为团体型参缴机制中参缴行为的效力规则的学理基础。在规范层面,应以团体型参缴义务为核心,将符合条件的组织型平台设定为参缴义务人,制定更具弹性的缴费和履行规则。通过明确社会保险行政部门的确认职权,以及工会监督缴费义务的职能,来强化参缴行为效力的保障措施。通过增加强制准入后的补缴规定和明确平台企业的拒缴责任,促进团体型参缴强制准入目的的有效实现。

医疗与人才:国民政府时期公医学生的培养、统制及变迁

国民政府时期,旨在促进医疗事业平民化、公共化的公医制度一度被引入中国进行尝试,并应这种制度的人才需求而催生了公医学生群体。公医学生在读书期间享受一定优惠政策,但毕业后却有一定的服务要求,就业不能自主。随着国民政府在高校学生中公费制度的实行及其范围的扩大,公医学生享受优惠政策的优势逐渐丧失。在此背景下,国民政府在抗战胜利后只得取消了公医学生服务的强制性要求。这一取消,虽然使公医学生得到了解脱,但客观上又无法保障公医制度的人才需求。

新就业形态下如何破局劳动者工伤保险不完全覆盖困境——基于众包骑手群体的演化博弈分析

新就业形态下劳动者的工伤保险参保覆盖对于新就业形态的健康发展至关重要。以职业伤害风险较高且从属性偏弱的众包骑手群体为对象,从工伤保险覆盖的供需主体利益均衡视角,构建即时配送平台、众包骑手与政府的三方演化博弈模型,探究众包骑手工伤保险不完全覆盖困境生成的内在机理,推进众包骑手形成参保覆盖的具体措施。利用MATLAB仿真验证博弈分析的相关结果。研究发现:骑手遭受职业伤害的概率会影响骑手对商业保险经济补偿与平台对骑手赔偿的期望收益判断,从而影响骑手的参保策略选择;骑手参保下的订单量与单价下降损失高于商业保险资金成本,商业保险经济补偿低于平台对骑手赔偿是造成骑手工伤保险不完全覆盖困境的直接原因;政府是推动骑手工伤保险参保覆盖的关键主体,通过降低骑手参保下的损失与平台工伤保险缴纳费率,提高对平台“漏保”行为的处罚与平台对骑手赔偿等措施,能够加快推进骑手工伤保险的参保覆盖。

老年人社会参与实践考察与保障机制研究——以昆明市为例

社会参与是积极老龄化应对全球人口挑战提出的重要任务之一。以社会参与理念落地为研究背景,以昆明市老年人社会参与实践考察数据为例,从老年人社会参与实践特征维度予以分析。结果显示:昆明市老年人社会参与存在缺乏理论与制度保障、就业权益缺乏法律保障、社会参与能力不足的问题。对此,应通过优化老年人社会参与政策制度、完善老年人社会参与平台建设、分类管理指导老年人社会参与工作、优化老年人社会参与能力与环境四个保障机制推进积极老龄化发展。

灵活用工下大学生兼职法律关系探究

我国灵活用工主要包括劳务合同用工、劳务派遣用工、非全日制用工三种形式,大学生参与灵活用工的比例显著增加。劳务合同用工下之大学生兼职主要是指大学生勤工助学。劳务派遣下大学生兼职存在诸多问题。劳务派遣公司不可以把实习大学生派遣到用工单位进行实习。学校、实习单位、学生三方必须以有关部门发布的实习协议示范文本为基础签订实习协议,明确各方的权利和义务。非全日制用工下之大学生兼职法律关系应适用劳动法保护。

G54钢的动高压性能实验研究

G54钢是我国自主研制的一种新型超高强度钢,具有较高的潜在应用价值。为了研究该材料的动高压性能,为应用推广提供数据支撑,采用火炮作为加载手段,开展了G54钢的飞片对称碰撞实验。实验飞片速度为600~1400 m/s,通过测量G54钢样品的背表面粒子速度-时间历史,获得了典型的冲击相变及层裂信号。通过对粒子速度进行分析,结合材料密度及声速测试结果,获得了冲击压力为13~23 GPa下G54钢的Hugoniot弹性极限、层裂强度、冲击波速度-粒子速度(D-u)关系以及冲击相变点等动高压性能参数。对实验样品进行回收及金相分析发现,随着飞片速度的增加,材料层裂面的损伤机制逐渐从微孔洞聚合主导的韧性断裂向绝热剪切主导的韧性断裂转变。

限定域关系抽取技术研究综述

限定域关系抽取技术是在预定义实体类型和关系类型的前提下,从文本中捕获关键信息的技术,多采用由头尾实体和关系构成的三元组作为信息表示形式。作为信息抽取领域的重要研究方向之一,其在知识问答、信息检索等任务中被广泛应用。文中在介绍相关概念和任务范式的基础上,分析了深度学习背景下限定域关系抽取任务的研究进展,根据句中实体是否可见,分为关系分类任务和三元组抽取任务,依据任务表现特征,前者可细分为有监督条件下的关系分类任务、小样本关系分类任务和远程监督条件下的关系分类任务。文中探讨和分析了以上任务中常用的技术方法及其优缺点,最后归纳总结了关系抽取技术在低资源、多模态等更为接近真实情景下的发展潜力和现存的挑战。