Sharif Digital Repository

Network forensic analysts employ payload attribution systems (PAS) as an investigative tool, which enables them to store and summarize large amounts of network traffic, including full packet payload. Hence an investigator could query the system for a specific string and check whether any of the packets transmitted previously in the network contained that specific string. As a shortcoming, the previously proposed techniques are unable to support wildcard queries. Wildcards are an important type of query that allow the investigator to locate strings in the payload when only part of the string is known. In this paper, a new data structure for payload attribution, named Character Dependent... 

Aluminum reinforced with a large amount (up to about 55 vol.%) of Al 3Ti particles can be fabricated from Al-20Ti elemental nanometer-sized powder mixture via in-situ two step hot press sintering (TSS). For production of intermetallic reinforced in-situ composite, TSS can provide elevated temperature to facilitate the formation of intermetallic phase in situ and hot consolidation to form a fully dense solid. The first step sintering was employed at a higher temperature to obtain an initial high density, and the second step was held at a lower temperature by isothermal sintering for more time than the first one to increase bulk density without significant grain growth. The optimum TSS regime... 

Site visits of selected factories and mines show large amounts of coal were collected as spoil and waste outside these locations due to un-efficiency of coal exploiting technology from mined material. The coal content of these waste materials is about 60%. In this work, we propose a method to be used for complete consumption of these materials in industry. In some samples, volume and weight of spoils could be decreased by half. This review also shows that aluminum oxide in industrial and minerals spoils are high, in some samples up to 25%. We suggest some remedies, e.g. we can use ashes produced by complete combustion of coal for production of aluminum hydroxide thus making it economical.... 

Peer-to-peer networks (P2P) are beginning to form the infrastructure of future applications. One of the problems with unstructured P2P networks is their scalability limitation. This is also the problem in structured P2P networks that use broadcasting to find objects. These networks can't contain a large number of nodes because of the large amount of traffic that they have to handle. Local indexing is a method to reduce this traffic. But local indexes tend to become large with the growth of the network. Also limiting the size of these indexes causes loss of indexing information. In this paper we introduce a novel ontology based local index which limits the size of the local indexes without... 

The building sector is a major source of energy consumption and greenhouse gas emissions in urban regions. Several studies have explored energy consumption prediction, and the value of the knowledge extracted is directly related to the quality of the data used. The massive growth in the scale of data affects data quality and poses a challenge to traditional data mining methods, as these methods have difficulties coping with such large amounts of data. Expanded algorithms need to be utilized to improve prediction performance considering the ever-increasing large data sets. In this paper, a preprocessing method to remove noisy features is coupled with predication methods to improve the...