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21.
Luis Villar-Fidalgo María del Mar Espinosa Escudero Manuel Domínguez Somonte 《生产规划与管理》2019,30(8):624-638
Not only ETO (Engineering to Order), but even serial production industry should know how to deal with projects and their schedule: plant commissioning, shutdown, introducing new products and similar circumstances should be managed with adequate planning and resource allocation techniques to create a schedule useful in decision making during the execution. The current complex reality, with evolving technologies and fierce pressure to reach the market as soon as possible, pushes the project managers to use more advanced techniques than waterfall planning, such as agile or lean. It also requires them to take a holistic view and manage concurrent tasks in complex projects. The contributions of this paper are two: the proposal to control specific parallel groups of waterfall activities under uncertain environments, which can lead to iterations and reworks, as a single concurrent Activity Managed by Kanban Methods (AMKM). This activity can be subsequently embedded into traditional scheduling approaches as CPM-PERT. The second contribution is the feasibility of its application in industrial environments due to the affordability of simulation software. Two use cases are shown as evidence. It is not a disruptive proposal, but a kaizen action based on very mature technologies. Finally, it is suggested some improvements to be implemented in Project Management Software due to this ‘kaizen’ proposal. 相似文献
22.
Sant’Anna Annibal Parracho de Freitas Siqueira Sadok Menna Barreto Márcia 《Social indicators research》2020,148(3):733-746
Social Indicators Research - This paper analyses the Human Development Index (HDI) time series from 2010 to 2017. An alternative index is studied, which combines the same components of the HDI by... 相似文献
23.
This paper develops a unified model of dual and unitary job holding based on a Stone-Geary utility function. The model incorporates both constrained and unconstrained labor supply. Panel data methods are adapted to accommodate unobserved heterogeneity and multinomial selection into six mutually exclusive labor supply regimes. We estimate the wage and income elasticities arising from selection and unobserved heterogeneity as well as from the Stone-Geary Slutsky equations. The labor supply model is estimated with data from the British Household Panel Survey 1991–2008. Among dual job holders, our study finds that the Stone-Geary income and wage elasticities are much larger for labor supply to the second job compared with the main job. When the effects of selection and unobserved heterogeneity are taken account of, the magnitudes of these elasticities on the second job tend to be significantly reduced. 相似文献
24.
This article studies design selection for generalized linear models (GLMs) using the quantile dispersion graphs (QDGs) approach in the presence of misspecification in the link and/or linear predictor. The uncertainty in the linear predictor is represented by a unknown function and estimated using kriging. For addressing misspecified link functions, a generalized family of link functions is used. Numerical examples are shown to illustrate the proposed methodology. 相似文献
25.
AbstractIn general, survival data are time-to-event data, such as time to death, time to appearance of a tumor, or time to recurrence of a disease. Models for survival data have frequently been based on the proportional hazards model, proposed by Cox. The Cox model has intensive application in the field of social, medical, behavioral and public health sciences. In this paper we propose a more efficient sampling method of recruiting subjects for survival analysis. We propose using a Moving Extreme Ranked Set Sampling (MERSS) scheme with ranking based on an easy-to-evaluate baseline auxiliary variable known to be associated with survival time. This paper demonstrates that this approach provides a more powerful testing procedure as well as a more efficient estimate of hazard ratio than that based on simple random sampling (SRS). Theoretical derivation and simulation studies are provided. The Iowa 65+ Rural study data are used to illustrate the methods developed in this paper. 相似文献
26.
Economic theory establishes that pension privatization weakens the link between old and young and so reduces the incentive to invest in public education in an economy with lower return rate of capital than growth rate of wage. However, empirical studies of the link change are few. In this paper, we investigate the effects of pension privatization and the central government’s subsidy to individual accounts on public education spending in a three-period overlapping generation model. And then, we take contemporary pension reforms in a number of Chinese provinces as offering natural experiment conditions. Using a difference-in-difference framework and 282 municipal districts panel data over years 1998–2009, we test the pension-education theoretical link change. Both our theoretical and empirical results confirm that pension privatization is adversely associated with local public spending on education in China. Private pension subsidies, moreover, magnify this effect. Our study supports the theoretical assertion and selective empirical findings of a negative intergenerational effect of pension privatization. 相似文献
27.
28.
Adrian D. Van Breda 《Journal of youth studies》2015,18(3):322-337
The journey out of care and towards independent living is a challenge for many care-leavers. There has been little research into the social processes involved in this care-leaving journey. This paper presents the results of a grounded theory investigation into the care-leaving journeys of nine young men who had, several years previously, been in the care of Girls & Boys Town in South Africa. Working from a resilience perspective, with an ecological emphasis, four central social processes emerged that together explain the care-leaving experiences of the participants. These processes are striving for authentic belonging; networking people for goal attainment; contextualised responsiveness and building hopeful and tenacious self-confidence. These four processes are located within contextual boundaries and at the social environmental interface. The paper presents these processes in detail, drawing on selected narratives of the participants and integrated with additional theory. It is hoped that this paper may contribute to theory building concerning care-leaving processes and enhance youth care practices for youth in care and leaving care. 相似文献
29.
From the inception of the proportional representation movement it has been an issue whether larger parties are favored at
the expense of smaller parties in one apportionment of seats as compared to another apportionment. A number of methods have
been proposed and are used in countries with a proportional representation system. These apportionment methods exhibit a regularity
of order, as discussed in the present paper, that captures the preferential treatment of larger versus smaller parties. This
order, namely majorization, permits the comparison of seat allocations in two apportionments. For divisor methods, we show
that one method is majorized by another method if and only if their signpost ratios are increasing. This criterion is satisfied
for the divisor methods with power-mean rounding, and for the divisor methods with stationary rounding. Majorization places
the five traditional apportionment methods in the order as they are known to favor larger parties over smaller parties: Adams,
Dean, Hill, Webster, and Jefferson.
Received: 5 August 2000/Accepted: 24 October 2001 相似文献
30.
This study replicated and extended previously reported sex differences involving both viewer and target in the recognition of threatening facial expressions. Based on the assumption that the evolved cognitive mechanisms mediating anger recognition would have been designed by natural selection to operate quickly in the interests of survival, brief tachistoscopic presentation of stimulus photographs was used. Additionally, in contrast to prior published studies, the statistical methods of signal detection research were used to control for the confounding effects of non-random guessing. The main hypothesis, that anger posed by males would be more accurately perceived than anger posed by females, was supported. A secondary hypothesis, that female-posed anger would be more accurately perceived by women than by men, received partial support. Testosterone levels, measured inferentially in terms of diurnal cycles, failed to show the hypothesized positive relationship to accuracy of anger perception. 相似文献