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1.
Journal of Business Ethics - Blockchain is an open digital ledger technology that has the capability of significantly altering the way that people operations (i.e. human resource management)...  相似文献   
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Models that link ecological responses to hydrologic changes are important for assessing the effects of flow regulation on aquatic and riparian ecosystems. Based on the Recruitment Box Model, a graphical model used to prescribe environmental flows for cottonwood (Populus spp.) recruitment, we designed a simulation model to represent the influence of river flow dynamics on seedling recruitment of riparian pioneer woody plants. The model simulates the influence of temporal patterns of river stage on dispersal, germination, initial recruitment and over‐winter survival of first‐year seedlings of riparian pioneer shrubs and trees. We used the model to simulate seedling recruitment patterns for five species (Acer saccharinum, Betula nigra, Populus deltoides, Salix nigra and Salix exigua) on the Wisconsin River (Wisconsin, USA) under three flow scenarios: historic (1935–2002), simulated natural (1915–1975) and simulated regulated flows (1915–1975). Simulation results agreed well with field‐observed relative differences among years (1997–2000) in seedling densities for the five focal species. Simulated successful recruitment years were highly synchronous among species, but species differed in their sensitivity to flows at different times during the growing season, consistent with among‐species differences in seed dispersal timing. Comparison of simulated natural and regulated flows for 1915–1975 showed that flow regulation decreased monthly flow variability, increased late summer to winter baseflow and reduced the magnitude of spring peaks. Simulated recruitment and over‐winter survival of tree seedlings of all species was enhanced under the regulated flow scenario, likely due to increased summer baseflow and reductions in peak flood magnitude. Our analyses show the utility of extending the Recruitment Box Model to include multiple species of riparian shrubs and trees, and the effects of post‐colonization flows on their recruitment success. However, some key functional relationships between flow patterns and woody seedling demography (e.g. shear stress thresholds for seedling mortality) have not been adequately quantified and merit further study. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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The literature on US state government fiscal performance has examined the role of institutional factors such as budget rules and divided government, but has largely ignored the impact of party alternation. This paper primarily focuses on whether party alternation in the governor’s office affects fiscal performance. Our hypothesis is that frequent party changes create a political environment that impacts fiscal performance. To further assess the impact of party alternation on fiscal performance, we consider our primary hypothesis in conjunction with the degree of division that exists between the governor’s office and the legislature. Using panel data from 37 states between 1971 and 2000 we test the hypothesis that frequent party alternation can be expected to affect fiscal performance and find strong support for the hypothesis. An earlier version of this paper was presented at the 2005 Public Choice Society Meetings. The authors would like to thank the conference participants, William Shughart, Charles Register, Jocelyn Evans, John D. Jackson, Amihai Glazer, and two anonymous referees for their comments. We would also like to thank Craig R. Stiller for his help in the collection of data. Any remaining errors remain the responsibility of the authors.  相似文献   
5.
The quantification of soil variability is one of the most important aspects in the geo-engineering context. The uncertainty analysis is the main part of the reliability assessment for which a quantitative evaluation was performed in this study. The Reliability Index and the Probability of Failure using the First-Order Reliability Method (FORM) represents both, an effective method which is easy to implement at the same time. This work analyzes possible effects of compaction induced into the aquifer of the Scarlino Plain, caused by the extension of the hydraulic barrier for groundwater remediation. The currently implemented vertical barrier is composed of 12 wells which reach the depth of 10 m. The improvement of the project involves the construction of a further 40 clusters, each consisting of a doublet which intercepts different depths (10 and 18 m). The models of the subsoil stratigraphy and of the groundwater were built using a numerical model. The groundwater flow and the piezometric surface in the current configuration of the barrier were studied and the project configuration was evaluated. Using the Aquitard drainage model, the land subsidence was estimated to calculate the maximum admissible displacement related to exhibited goods, the so called territorial vulnerability. The evaluation analysis was performed using a traditional deterministic approach, followed by a reliability method based on probabilistic models. Finally, the respective results were reported in a soil mapping with overlapping layers.  相似文献   
6.
Many large lake ecosystems are experiencing increasing eutrophication and persistent cyanobacteria‐dominated algal blooms affecting their water quality and ecosystem productivity because of widespread non‐point and point nutrient sources. Accordingly, the present study utilized data of July 2003 and January–February 2004, as well as previous measurements of nutrients and physico‐chemical variables (electrical conductivity, dissolved oxygen, temperature, pH, turbidity and chlorophyll‐a), to characterize the spatial and temporal trends, as a means of better understanding the factors influencing lake environmental conditions, as support tools for long‐term ecosystem management and for better understanding the long‐term trends and effects. Inshore gulf areas were found to represent zones of maximum nutrient concentrations, compared to the deep main lake zones, with significant inter‐parameter correlations. Phosphorus, silicon and chlorophyll‐a concentrations were significantly correlated. Water electrical conductivity was also significantly and positively correlated with soluble reactive silicon (SRSi), alkalinity hardness DO, while exhibiting a negative association with water transparency. Water turbidity and transparency, electrical conductivity, and SRSi concentrations clearly describe a gradient from the gulf into the main lake. For such a shallow gulf, these findings suggest primary productivity is influenced mainly by the availability of nutrients, light transparency and the extent of availability of resuspended nutrients. The increasing eutrophic state of Lake Victoria is a serious concern since it contributes to an increased potential of more frequent occurrences of cyanobacterial blooms, a potential public health risk to both humans and wildlife. Improved understanding of influences from previous fish species introductions and concomitant changes in indigenous fish species, increased lake basin population and anthropogenic activities, water hyacinth resurgences, sustainability of biodiversity, and current interests in cage farming, are among the major concerns and challenges facing the contemporary Lake Victoria. The trends regarding nutrients and physico‐chemical characteristics are intended to support better monitoring efforts and data to promote the lake's ecosystem services and the sustainable management of the lake ecosystem.  相似文献   
7.
We describe a common pool resource game in which players choose how much of the stock to extract in a sequential manner. There are two choices and one represents taking a larger proportion of the stock than the other. After a player makes a choice, the remaining stock grows at a constant rate. We consider a game with a finite number of alternating moves. It is shown that changes in the larger proportion of the stock that the players are allowed to take and the growth rate affect equilibrium, but have little effect on behavior in the laboratory. In addition to observing more cooperation than predicted, we observe that parameters that are strategically irrelevant affect behavior. The results of this research might help policy makers in developing adequate policies to prevent overexploitation of some natural renewable resources.  相似文献   
8.
Si considera la classe delle funzioni realiF(x,y) definite inS×S, conSR N , che soddisfano per ognix,yS la condizione di monotoniaF(x,y)+F(y,x)0. Indebolendo la precedente disuguaglianza si introducono classi di funzioni monotone generalizzate e, supponendo soddisfatta una opportuna condizione di omogeneità, si caratterizzano tali funzioni in base alla struttura del segno delle funzioni x, v (t, s) = F(x + tv, x + sv), x S, v R N \{0}. Infine dopo aver definite le funzioni F-differenziabili, si introducono classi di funzioni conversse generalizzate, rispetto ad F, e si studiano i collegamenti tra queste classi e la monotonia generalizzata diF.
Summary We consider the class of real valued functionF(x,y) defined inS×S, withSR N , satisfying x,yS the monotone conditionF(x,y)+F(y,x)0. Weakening the previous inequality we introduce the class of quasi-monotone, pseudo-monotone and strictly pseudo-monotone functions. Under a suitable assumption of homogeneity we characterize the generalized monotone functions studying the sign structure of the functions x, v (t, s) = F(x + tv, x + sv), x S, v R N \{0}.Finally by means of the notion ofF-differentiability we introduce new classes of generalized convex functions (with respect toF) and we study the relationship between these classes and the generalized monotonicity ofF.


Questa ricerca è stata parzialmente finanziata dal Ministero per l'Università e la Ricerca Scientifica.  相似文献   
9.
This paper examines the influence of integrated reporting (IR) on the sustainability reporting practices of a state-owned enterprise through a content analysis of their reports and interviews with report preparers. The findings show a steady increase in the quantity and quality of sustainability disclosures. In 2012, the organization chose to adopt the IR framework in order to enhance sustainability reporting for all stakeholders. The IR process resulted in a more balanced disclosure of material aspects of sustainability. However, while IR has the potential to enhance public sector sustainability reporting, inter-generational equity issues were ignored.  相似文献   
10.
Despite the increased use of seasonal employees by organizations, few studies have been completed on the attitudes and service quality of seasonal office workers. Using Lautsch's classification model, we analyzed the organizational context in which the standard and seasonal workers in this study were employed. Hypotheses were developed based upon the organizational analysis and social exchange theory. Results from archival data obtained from a web‐based organizational survey of 205 clerical and professional workers indicated contrary to expectations, standard and seasonal employees did not significantly differ in terms of perceptions of overall job conditions, perceived organizational support (POS), or job engagement. However, seasonal employees did report significantly fewer opportunities to work on challenging tasks, less comfortable physical working conditions, and less job security than the standard workers. As predicted, standard employees reported significantly higher levels of service quality performance than seasonal employees. Additionally, job engagement mediated the relationship between POS and service quality for both the standard and seasonal employees. Implications for managing seasonal employees are discussed.  相似文献   
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