General standby allocation in series and parallel systems

Stochastic orders are very useful tools to compare the lifetimes of two systems. Optimum lifetime of a series (resp. parallel) system with general standby component(s) depends on the allocation strategy of standby component(s) into the system. Here, we discuss three different models of one or more standby components. In each model, we compare different series (resp. parallel) systems (which are formed through different allocation strategies of standby component(s)) with respect to the usual stochastic order and the stochastic precedence order. The results related to the cold as well as the hot standby models are obtained as particular cases of the results discussed in this article because the model considered here is a general one.     

Life and labor on the internal colonial edge: Political economy of kolberi in Rojhelat

Through the investigation of kolberi (cross-border labor), this paper sheds light on the state’s policy of de-development (or internal colonialization) of the Kurdish region (known as Rojhelat) in Iran. While the most dangerous form of labor, kolberi has become a dominant employment opportunity for Rojhelat Kurds in the last decade. There are no Iranian state laws criminalizing kolberi, and yet those laborers die on a regular basis—being shot or thrown off mountain cliffs by the state forces, stepping into minefields, and so forth. Nevertheless, there is not a single scholarly paper on this subject. Using the mixed methods research approach, our study analyzes the existing data along with in-depth interviews with 20 people who are currently engaged in kolberi to contextualize this understudied phenomenon. Our finding demonstrates that kolberi is a direct outcome of a uni-ethno-religious policies of development and part and parcel of the state's Perso-Shi‘ification strategy in Kurdistan. Therefore, kolberi is more of a political phenomenon than an economic one.     

全球化与哲学的可能性

笔者认为哲学必须要“解决时代提出的问题”,“阐明事物的本质”,哲学具有完成这一任务的“可能性”。在全球化时代,哲学尤其要解决由“市场竞争”导致的精神问题以及其它全球性问题。现代已经成为最需要哲学的时代。     

关于声发射法在塑性加工中应用的研究——塑性加工界面摩擦润滑状态的分析(Ⅱ)

本文用声发射法分析了塑性加工界面摩擦润滑状态。得到了金属拉拔时,声发射事件总数与拉拔速度,断面收缩率,润滑油粘度之间的关系。从声发射参数的变化,可看出界面状态变化的情况。因此,用声发射法可对塑性加工界面上的摩擦润滑状态的变化,进行动态下实时监测,进而可为产品的加工质量监控,提供新的方法。     

Antecedents of gender gap in workforce participation: A phenomenology of psychologists and medical doctors in urban Pakistan

ABSTRACT

In recent years, the participation of young women in education has been on the rise and yet many of them do not end up joining the workforce. This is particularly true for the fields of medicine, and psychology. Using a qualitative research design, we explored underlying social and psychological reasons (antecedents) for this lack of professional participation by females who had or are graduating in medical and psychology degrees. The sample of this qualitative study consisted of 67 female informants including medical doctors, medical students, psychologists, and psychology students. The results based on interpretive phenomenological analyses (IPA) indicated multiple key antecedents that play a crucial role in keeping women from their professional participation in the two fields. Results based on IPA indicated that Gender Role Beliefs and Strain, Economic Decision Making, Women’s Mobility, Role of Society, Objectification of Women and explicit Discrimination and Violence were key thematic antecedents. There were multiple subthemes that emerged as reasons why women’s participation and stay in these fields was difficult, hence creating a substantial gender gap in professional participation and success in the workforce. Knowledge and understanding of these antecedents and their role in prevalence of gender gap in workforce participation is crucial for building policies and strategies on how to engage and retain women in professional work-force. Cultural relevance and societal implications of our findings are discussed with their policy recommendations.     

A polynomial-time perfect sampler for the <Emphasis Type="Italic">Q</Emphasis>-Ising with a vertex-independent noise

We present a polynomial-time perfect sampler for the Q-Ising with a vertex-independent noise. The Q-Ising, one of the generalized models of the Ising, arose in the context of Bayesian image restoration in statistical mechanics. We study the distribution of Q-Ising on a two-dimensional square lattice over n vertices, that is, we deal with a discrete state space {1,…,Q} ⁿ for a positive integer Q. Employing the Q-Ising (having a parameter β) as a prior distribution, and assuming a Gaussian noise (having another parameter α), a posterior is obtained from the Bayes’ formula. Furthermore, we generalize it: the distribution of noise is not necessarily a Gaussian, but any vertex-independent noise. We first present a Gibbs sampler from our posterior, and also present a perfect sampler by defining a coupling via a monotone update function. Then, we show O(nlog n) mixing time of the Gibbs sampler for the generalized model under a condition that β is sufficiently small (whatever the distribution of noise is). In case of a Gaussian, we obtain another more natural condition for rapid mixing that α is sufficiently larger than β. Thereby, we show that the expected running time of our sampler is O(nlog n).     

Naturalization as a strategy for improving soil physical characteristics in a forested urban park

Ensuring good soil quality is essential to promoting plant growth in urban parks and building ecological resilience into a cityscape. Periodically used to restore a degraded urban ecosystem, parkland naturalization is a management approach designed to facilitate the return of an area to a natural state by largely discontinuing maintenance activities and restricting public access. This study investigates the potential for parkland naturalization to improve soil quality in a forested portion of Kew Gardens Park, Toronto, Canada by comparing soil physical properties in three six-year-old naturalization enclosures with those found in adjacent managed parkland. Soil texture, compaction, bulk density, and surface water infiltration rate were measured at 104 sample sites, while ordinary kriging was used to interpolate two-dimensional prediction surfaces representative of soil properties. Sand and loamy sand were the dominant soil texture classes found across the study site. Highly compacted soil (>2,000 kPa) and soil with a bulk density >1.8 Mg/m³ (values sufficiently elevated to restrict tree root growth and respiration and impair soil water infiltration) were spatially correlated with high pedestrian traffic areas and corridors used by festival and park maintenance vehicles. In contrast, compaction and bulk density measurements in the naturalized areas were at or below thresholds known to impair root function ([`(X)] {{\overline{X}}} at 10 and 30 cm depth: 849 and 1,311 kPa, 1.15 and 1.51 Mg/m<sup>3</sup>, respectively). Similarly, water infiltration rates were rapid ( [`(X)] = 470mm/hr ) \left( {{{\overline{X}}} = {47}0{\hbox{mm}}/{\hbox{hr}}} \right) within the naturalization enclosures but retarded to the point of surface pooling in parkland subjected to regular public use. In the absence of quantitative baseline data, our use of spatial analysis demonstrates that parkland naturalization is a good management practice for restoration of soil physical characteristics. While our results show improvements to soil properties in a relatively short period of time, variability in the soil response rate to parkland naturalization will be dependent upon disturbance history as well as on soil and climate type.