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With sustained growth of intermittent power supplies connected to grid, the randomness and volatility of intermittent power supplies will bring new challenges to power system optimization dispatch. For dealing with the uncertainty of large-scale intermittent power supply, this paper introduces robust optimization theory into optimization dispatch for hybrid wind/photovoltaic/hydro/thermal power systems. Meanwhile in order to make an ideal compromise between reliability and economy of system dispatch, this paper also introduces concept of uncertainty to cover shortcoming of conventional robust optimization which is conservative. A flexible robust optimization with adjustable uncertainty budget dispatch model is built for hybrid power system to achieve coordination between reliability and economy, and then the uncertainty budget decision methods are studied to reduce blindness of uncertainty budget decisions. Moreover, a new compound differential evolution (CDE) algorithm is designed in this paper. The diversity of individuals and convergence speed are taken into account in process of differential evolution (DE) calculation by introducing a series of operations into DE algorithm, such as individual ranking, population dividing, CDE, and population restructuring. Finally, a sample application is carried out to verify the validity and practicability of the model and the method.Index Terms-Adjustable uncertainty budget, compound differential evolution (CDE) algorithm, intermittent power supplies, optimization dispatch, robust optimization. NOMENCLATURE Sets XDecision variable set. U Bounded uncertainty set. R # t Set of intermittent power supplies of extreme output. he is currently a Professor. His current research interests include operations, planning, and economics of power systems, optimization, stochastic programming, and electricity markets.

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The Zimbardo Time Perspective Inventory (ZTPI) is one of the most well-known and widely used measures of time perspective. Various short versions were proposed to resolve the psychometric problems of the ZTPI. The present study conducted a systematic review to obtain 25 short versions, calculated the frequency of each item of the ZTPI in short versions, and hypothesized that the more frequent the item is, the more robust it becomes. The hypothesis was tested by assessing the structural validity and internal consistency of short forms with high, medium, and low frequent items in Chinese samples (575 children, 407 undergraduates, and 411 older adults). Structural validity and internal consistency analyses showed that the form with more frequent items had better psychometric properties; item frequencies were positively correlated with factor loadings. The results suggest that the systematic review is an effective approach to identify the robust items of the ZTPI. This approach is general and can be the basis to improve the psychometric properties of scales in social science.

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