22 research outputs found

    Hybrid Approach for Resource Provisioning in Cloud Computing

    Get PDF
    Cloud computing is a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources that can be rapidly provisioned and released with minimal management effort or service provider interaction. Elasticity of resources is considered as a key characteristic of cloud computing using this key characteristic; internet services are allocated the only-needed resources. This allocation of resources however should not be at the expense of the services’ performance. Allocation of resources without degrading performance is called resource provisioning. Resource provisioning does not only support the elasticity of resources, but also enhances cost efficiency and sustainability. The goal of this work is to investigate resource provisioning to increase the percentage of resources utilization without degrading the performance so that the power consumption of the cloud data centers is reduced. To achieve this goal, a hybrid-approach for resource provisioning is developed. In this approach, a list of virtual machines is requested, passed to a selection algorithm, sorting the machines according to their load, compute the threshold of the machines’ load, and combining the high load with low load from two different virtual machines on one super virtual machine. The approach was implemented in a simulator called CloudSim. It was used to run two sets of experiments. The first is to measure the power consumption of the data center as whole and hosts as well. And the second is concerned with the processing times and memory usage.  The results have shown that this approach outperforms traditional counterparts in resource provisioning. The results showed that the hybrid approach achieved reduction of (5.85 MW/s) in power consumption compared with the traditional counterparts for the whole data center, as well as reduction of (2.48 MW/s) in power consumption for the hosts

    Effectiveness of query expansion in searching the Holy Quran

    Get PDF
    Modern Arabic text is written without diacritical marks (short vowels), which causes considerable ambiguity at the word level in the absence of context. Exceptional from this is the Holy Quran, which is endorsed with short vowels and other marks to preserve the pronunciation and hence, the correctness of sensing its words. Searching for a word in vowelized text requires typing and matching all its diacritical marks, which is cumbersome and preventing learners from searching and understanding the text. The other way around, is to ignore these marks and fall in the problem of ambiguity. In this paper, we provide a novel diacritic-less searching approach to retrieve from the Quran relevant verses that match a user’s query through automatic query expansion techniques. The proposed approach utilizes a relational database search engine that is scalable, portable across RDBMS platforms, and provides fast and sophisticated retrieval. The results are presented and the applied approach reveals future directions for search engines

    Implementing bi-temporal properties into various NoSQL database categories

    Get PDF
    © Research Institute for Intelligent Computer Systems, 2019. NoSQL database systems have emerged and developed at an accelerating rate in the last years. Attractive properties such as scalability and performance, which are needed by many applications today, contributed to their increasing popularity. Time is very important aspect in many applications. Many NoSQL database systems do not offer built in management for temporal properties. In this paper, we discuss how we can embed temporal properties in NoSQL databases. We review and differentiate between the most popular NoSQL stores. Moreover, we propose various solutions to modify data models for embedding bitemporal properties in two of the most popular categories of NoSQL databases (Key-value stores and Column stores). In addition, we give examples of how to represent bitemporal properties using Redis Key-value store and Cassandra column oriented store. This work can be used as basis for designing and implementing temporal operators and temporal data management in NoSQL databases

    The simultaneous impact of EV charging and PV inverter reactive power on the hosting distribution system's performance: A case study in kuwait

    Get PDF
    Recently, electric vehicles (EVs) have become an increasingly important topic in the field of sustainable transportation research, alongside distributed generation, reactive power compensation, charging optimization, and control. The process of loading on existing power system infrastructures with increasing demand requires appropriate impact indices to be analyzed. This paper studies the impact of integrating electric vehicle charging stations (EVCSs) into a residential distribution network. An actual case study is modeled to acquire nodal voltages and feeder currents. The model obtains the optimal integration of solar photovoltaic (PV) panels with charging stations while considering reactive power compensation. The impact of EV integration for the case study results in two peaks, which show a 6.4% and 17% increase. Varying the inverter to the PV ratio from 1.1 to 2 decreases system losses by 34% to 41%. The type of charging is dependent on the maximum penetration of EVCSs that the network can install without system upgrades. Increasing the number of EVCSs can cause an increase in power system losses, which is dependent on the network architecture. Installing PV reduces the load peak by 21%, and the installation of PV with consideration of reactive power control increases system efficiency and power delivery. 2020 by the authors.Scopus2-s2.0-8509088409

    A Visual Cryptography Based Watermark Technology for Individual and Group Images

    No full text
    The ease by which digital information can be duplicated and distributed has led to the need for effective copyright protection tools. Various techniques including watermarking have been introduced in attempt to address these growing concerns. Most watermarking algorithms call for a piece of information to be hidden directly in media content, in such a way that it is imperceptible to a human observer, but detectable by a computer. This paper presents an improved cryptographic watermark method based on Hwang and Naor-Shamir [1, 2] approaches. The technique does not require that the watermark pattern to be embedded in to the original digital image. Verification information is generated and used to validate the ownership of the image or a group of images. The watermark pattern can be any bitmap image. Experimental results show that the proposed method can recover the watermark pattern from the marked image (or group of images) even if major changes are reflected on the original digital image or any member of the image group such as rotation, scaling and distortion

    Enhancing retrieval effectiveness of diacritisized Arabic passages using stemmer and thesaurus

    No full text
    In this paper we discuss the enhancement of Arabic passage retrieval for both diacritisized and nondiacritisized text. Most previous work suggested that retrieval start with pre-processing the Arabic text to remove the diacritical marks (short vowels) to unify the text. In most cases, this process causes considerable ambiguity at the word level in the absence of context. However, searching for a word in diacritisized text requires typing and matching all its diacritical marks, which is cumbersome and prevents users from searching and hence retrieving valuable amount of text. The other way around, is to ignore these marks and fall into the problem of ambiguity. In this paper, we propose a passage retrieval approach to search for diacritic and diacritic-less text through query expansion to match a user’s query. We applied a rule-based stemmer and we compiled a huge thesaurus for this purpose. We tested our approach on the scripts of the Quran as an open domain source of diacritisized text using a set of 40 non-diacritical words obtained from testers. The results are presented and the applied approach reveals future directions for search engines
    corecore