Why Frequency is Not Well Defined for Engineering Systems with Nonexponential Failure Times

Dr. Yellman proposes to define frequency as “a time‐rate of events of a specified type over a particular time interval.” We review why no definition of frequency, including this one, can satisfy both of two conditions: (1) the definition should agree with the ordinary meaning of frequency, such as that less frequent events are less likely to occur than more frequent events, over any particular time interval for which the frequencies of both are defined; and (2) the definition should be applicable not only to exponentially distributed times between (or until) events, but also to some nonexponential (e.g., uniformly distributed) times. We make the simple point that no definition can satisfy (1) and (2) by showing that any definition that determines which of any two uniformly distributed times has the higher “frequency” (or that determines that they have the same “frequency,” if neither is higher) must assign a higher frequency number to the distribution with the lower probability of occurrence over some time intervals. Dr. Yellman's proposed phrase, “time‐rate of events … over a particular time interval” is profoundly ambiguous in such cases, as the instantaneous failure rates vary over an infinitely wide range (e.g., from one to infinity), making it unclear which value is denoted by the phrase “time‐rate of events.”     

A note on spectral estimation for ARMA processes

The standard frequency domain approximation to the Gaussian likelihood of a sample from an ARMA process is considered. The Newton-Raphson and Gauss-Newton numerical maximisation algorithms are evaluated for this approximate likelihood and the relationships between these algorithms and those of Akaike and Hannan explored. In particular it is shown that Hannan's method has certain computational advantages compared to the other spectral estimation methods considered     

Marriage and gender inequality: work–family arrangements of Portuguese and British highly qualified women

This article examines work–family reconciliation processes in order to understand if, over the course of marital life, women become socially closer or further away from their partner. Drawing on work–life interviews with highly qualified women in Portugal and Britain, we compare these processes in two societies with different historical and social backgrounds. Findings reveal three main configurations of social (in)equality which emerge during married life: growing inequality in favour of the man, in favour of the woman or equality between spouses. With due attention to the importance of national specific factors, we present three main conclusions. First, (in) equality is built up over the course of marital life and female strategies for reconciling family and work are at the core of this process. Second, the national specificities can mould the effects of cross-national gender mechanisms. Third, the intersection between cross-cultural phenomena such as conservative attitudes towards domestic work and national specificities (such as the availability of part-time options) is a rather complex process which needs further research.     

Domestic help and the gender division of domestic labor during the COVID-19 pandemic: Gender inequality among Japanese parents

The enduring COVID-19 pandemic has gradually transformed our everyday lives. This study focuses on changes in work and family arrangements, with particular focus on changes in domestic help, and examines its impact on the division of domestic labor. Using a social survey of work and the family conducted in November 2020 and May 2021, the results show that from January 2020 (pre-pandemic) to May 2021, approximately 40% of respondents experienced a reduced gender gap for housework and childcare, while a large gender gap is still observed in the absolute frequency of undertaking domestic labor. Some lifestyle changes triggered by the pandemic, such as an increase in the use of takeaways or delivery meals, and the expansion of working from home, are found to be able to contribute a shift toward more equal sharing of domestic labor. However, the fact that the access to such lifestyle changes is more common among those with a relatively high income or high educational background suggests that the lifestyle changes imposed by the pandemic may exacerbate class disparities in the gender gap in domestic labor. Furthermore, the results show that decreased kinship support results in a greater childcare burden being placed on women.     

土地流转中为什么会形成大量小农复制

土地流转是实现规模化经营的前提之一,然而土地流转中却出现大量小农复制,从而影响土地流转的质量和效果。运用12省(自治区)2 553份农户问卷,详细分析土地流转中小农复制的现状及其形成原因。研究发现：(1)农户流转耕地面积不大,转入户流转面积20亩及以下的约占总转入户数的60.3％,转出户流转面积5亩及以下的约占总转出户数的74.38％,转出户中仍然经营土地的约占总转出户数的74％。(2)农业分工发达使生产更加方便、文化传统形成路径依赖、禀赋效应产生“价值幻觉”以及公共服务不健全使未来存在不确定性导致转出户流转部分土地。乡土社会限制土地流转范围和经营风险增加风险感知导致转入户流转小规模土地。     

从“用频”的角度看现代汉语中的“无标志词/有标志词”与“尊/卑”文化的关系

现代汉语中,词的“无标志/有标志”性与词背后“尊/卑”文化有着很强的对应关系.然而,这种对应关系也存在着不少问题,例如“父/祖父/曾祖父”等反例,必须注意特定的“语言使用者”这一限制性条件.从“用频”的角度出发可以进一步解释“无标志/有标志”性与词背后“尊/卑”文化的具体对应关系.对“司令/总司令”和“保姆/男保姆”这两组例子的分析,可以揭示运用这种对应关系在实际应用过程中的一些重要问题.     

日语教育中句群的实义切分与信息结构

信息结构是句子实际意义的切分，它与句群有着天然联系。本文通过对日语句群的信息结构的分析，指出了日语句子的实义切分标准是信息相对于听话人是已知或未知、信息在说话人语流中出现或未出现过、信息在目前是激活状态还是未激活状态、信息的预设或断言的实际情况等四项，同时讨论了句子的实义切分在日语句群教育中的应用。     

‘Dirty Work?’ Gender,Race and the Union in Industrial Cleaning

The study uses an eclectic framework and through an intersectional analysis and use of narratives explores the meaning of janitorial work, the gender division of labour (GDL), the unions and organizing for janitors engaged in industrial cleaning for a big cleaning company, Pluto, in Toronto. Pluto was organized by the Service Employees International Union (SEIU) in 2006. The study is based on the organizing drive for Pluto and uses participant observation and interview methods. Intersectional analysis is useful in understanding the worker's perceptions of the racialized, gendered and classed constitution of cleaning work as ‘dirty’ and their resistance to these constructs. We explore GDL in industrial cleaning and the construction of women's work as ‘light duty’ and men's work as ‘heavy duty’. We conclude that union membership is important not only for material benefits of the janitors but also for their alternative identity construction. However, there is a persistence of GDL and gender pay equity is not addressed seriously in the organizing drive or upon organizing.     

试析影响词汇访问速度的关键因素

一些高频词汇在学习者大脑词库中常被存储在底层,如何把这些需要熟练使用的词汇尽可能多地转移到词库表层,以达到词汇访问的自动化,是值得探索和研究的问题。本文从词汇访问频率、词汇意义变化和语境三方面分析影响词汇访问速度的原因,并提出外语学习过程中提高词汇访问速度的建议。     

传统性别分工对选用女性干部的影响——基于湖南省某市两次干部考试的思考

当今各级政府干部选用,性别因素在一定程度上起着一定作用,从而导致女性参政处于不利地位。究其原因最为关键的是传统性别分工所带来的影响所致,这种影响主要表现在两个方面：一是它导致了性别刻板角色的形成;二是它强化了带有偏见的社会性别文化。