This paper considers the problem of minimizing the response time for a given database workload by a proper choice of indexes. This problem is NP-hard and known in the literature as the Index Selection Problem (ISP). We propose a genetic algorithm (GA) for solving the ISP. Computational results of the GA on standard ISP instances are compared to branchand-cut method and its initialisation heuris...

We discuss methods for solving the key linear equations within primal-dual barrier methods for linear and quadratic programming. Following Freund and Jarre, we explore methods for reducing the Newton equations to 2× 2 block systems (KKT systems) in a stable manner. Some methods require partitioning the variables into two or more parts, but a simpler approach is derived and recommended. To justi...

Although much has been written about better aligning Information Systems (IS) with the business, too often organizations perceive software development as though it exists in its own little cocoon. Selection of a formal software development methodology (FSDM) is usually left to the IS area which focuses on the detail component levels and features of an FSDM. The authors instead approach an FSDM ...

The loess deposits widely distributed in the eastern Tibetan Plateau (ETP) are important archives for reconstructing paleoenvironmental changes and dust transportation history of Plateau. A lack sufficient investigations on source ETP has limited our understanding implications. Quartz luminescence sensitivity holds great potential tracing eolian sources. Numerous quartz have provided new insigh...

Location of non-stationary forced oscillation (FO) sources can be a challenging task, especially under resonance condition with natural system modes. In this case, the magnitudes oscillations could greater in places distant from source and spreads over large region power system. Detection, frequency identification filtering FO oscillatory components constitutes an initial critical step for appl...

The optically stimulated luminescence (OSL) dating method promises to provide reliable ages for various Quaternary archives. Coastal sedimentation in the Bohai Sea (northeastern China) since Middle Pleistocene has been influenced by paleoenvironmental and sea-level change, of which restricted using OSL approach multiple investigations. In this study, establish a robust chronological framework c...

An association between salt pans or dry lake beds and distinctive crescentic lake-floor sand mounds (1–10 m high, tens to hundreds of metres wide) is commonplace in desert systems. In the Makgadikgadi Basin northern Botswana, a debate about formative processes these landforms has persisted despite numerous morphometric, sedimentary geochronological analyses, with mound variously inferred be aeo...

Abstract For 3D optically stimulated luminescence (OSL) based dosimeters to be clinically applicable, certain standards must met. Among these are low detectable doses with high accuracy and precision, ideally comparable those of point-like detectors. By investigating a model the central part an OSL readout-system, we present estimate <?CDATA $\sim 4\cdot {10}^{7}\frac{{\rm{photons}}}{{\rm{Gy}}\...