Sharif Digital Repository

Consider a collection of files, each of which is a sequence of letters. One of these files is randomly chosen and a random subsequence of the file is revealed. This random subsequence can be the result of a random sampling of the file. The goal is to recover the identity of the file, assuming a simple greedy matching algorithm to search the file collection. We study the fundamental limits on the maximum size of the file collection for reliable recovery in terms of the length of the random subsequence. The sequence of each file is assumed to follow a hidden Markov model (HMM), which is a common model for many data structures such as voice or DNA sequences. The connection between this problem... 

The objective of this study is to calibrate Priestley-Taylor (PT) model for estimating open water evaporation from an arid region reservoir called Chahnimeh. Chahnimeh Reservoir which is situated in the Sistan area in the southeast of Iran is being affected by regional energy advection during May to October. Therefore, common models of open water evaporation estimation such as PT require calibration. PT method was calibrated for Chahnimeh Reservoir using a volume balance method. Results showed that PT coefficient, αPT, as a constant over the year varies between 2.47±0.09 and 1.20±0.03 for two different hydrologic conditions of dry and wet. It means that there is also an intra-annular... 

The sharing economy, defined by peer-to-peer interactions through a platform, has been gaining ground in recent years. In this study, we discuss the relative importance of customers' perceived motives to participate in the two most common models of the sharing economy: access-based consumption and ownership-transfer. We focus on taxi-hailing and post-delivery as examples of access-based consumption and second-hand trade as an example of the ownership-transfer. While these two contain heterogeneous business model patterns that can motivate customers differently, common motives are significant in both models. We study common motives and motives aligned with the business model patterns, which...