Sürdürülebilir Yeşil Kampüs Koleksiyonu / Sustainable Green Campus Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7755
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Master Thesis Estimation of Low Sucrose Concentrations and Classification of Bacteria Concentrations With Machine Learning on Spectroscopic Data(Izmir Institute of Technology, 2019) Mezgil, Bahadır; Baştanlar, Yalın; Baştanlar, YalınSpectroscopy can be used to identify elements. In a similar way, there are recent studies that use optical spectroscopy to measure the material concentrations in chemical solutions. In this study, we employ machine learning techniques on collected ultraviolet-visible spectra to estimate the level of sucrose concentrations in solutions and to classify bacteria concentrations. Some metal nanoparticles are very sensitive to refraction index changes in the environment and this helps to detect small refraction index changes in the solution. In our study, gold nanoparticles are used and we benefited from this property to estimate sucrose concentrations. The samples in different low sucrose concentration solutions are obtained by mixing the sucrose measured with precision scales with pure water and then the UV-Vis spectrum of each sample is measured. For the bacteria concentration solutions, spectra for six different bacteria concentrations are captured. Spectra of the same solutions are also captured before adding the bacteria. For each of these solutions, four sets are prepared where gold nanoparticles are not grown (minute 0) and grown for 4 minutes, 10 minutes and 12 minutes. After the dataset preparation, these spectrum measurements are transferred into MATLAB environment as sucrose concentration dataset and bacteria solution dataset. Then the necessary preprocessing steps are performed in order to get the most informative and distinguishing information from these datasets. The raw measurement values and processed spectrum measurements are trained with shallow Artificial Neural Networks (ANN) on MATLAB Deep Learning Toolbox and Support Vector Machine (SVM) on MATLAB Statistics and Machine Learning Toolbox. When the results of the conducted machine learning experiments are examined, success rate is promising for the estimation of sucrose concentrations and very high for classification of bacteria concentrations in pure water solution.Master Thesis A Dedicated Server Design for Physical Web Applications(Izmir Institute of Technology, 2019) Abdennebi, Anes; Ayav, TolgaWith the huge impressive technological improvements the world is witnessing where giants like Facebook, Google, Apple, Microsoft and other technology companies are offering different services to millions of clients, services which don’t take usually more than seconds to be within the users’ devices besides the Physical Web applications that makes things interacts, having entities and can be reached based on the proximity context without omitting the incoming IoT infrastructure that would make 20.4 billion devices connected by 2020, the amount of data transferred, and services provided will be enormous and along with that, the big energy consumer standing behind providing clients with the needed data and services instantly, the web servers. Although it has a magnificent performance and responds to billions of queries and requests, however, there is still a crucial point which must be highlighted, the remarkable amounts of energy consumption by these servers. Therefore, this work is proposing a new approach in order to reduce the energy consumption in such a scenario where the 18-core energy efficient computer Parallella board will be used in order to create an energy efficient server that can offer many services triggered by various devices or any ordinary web requests across any environment and to prove also that using a cluster of Parallella supercomputers may perform as other similar servers dealing with web content (e.g. Raspberry Pi server). We will show how would these boards work under low energy feeding where users can access a web content hosted on a Parallella cluster. The source codes of the project are available on GitHub.Master Thesis Intrusion Detection System Alert Correlation With Operating System Level Logs(Izmir Institute of Technology, 2009) Toprak, Mustafa; Aytaç, İsmail SıtkıInternet is a global public network. More and more people are getting connected to the Internet every day to take advantage of the Internetwork connectivity. It also brings in a lot of risk on the Internet because there are both harmless and harmful users on the Internet. While an organization makes its information system available to harmless Internet users, at the same time the information is available to the malicious users as well. Most organizations deploy firewalls to protect their private network from the public network. But, no network can be hundred percent secured. This is because; the connectivity requires some kind of access to be granted on the internal systems to Internet users. The firewall provides security by allowing only specific services through it. The firewall implements defined rules to each packet reaching to its network interface. The IDS complements the firewall security by detected if someone tries to break in through the firewall or manages to break in the firewall security and tried to have access on any system in the trusted site and alerted the system administrator in case there is a breach in security. However, at present, IDSs suffer from several limitations. To address these limitations and learn network security threats, it is necessary to perform alert correlation. Alert correlation focuses on discovering various relationships between individual alerts. Intrusion alert correlation techniques correlate alerts into meaningful groups or attack scenarios for ease to understand by human analysts. In order to be sure about the alert correlation working properly, this thesis proposed to use attack scenarios by correlating alerts on the basis of prerequisites and consequences of intrusions. The architecture of the experimental environment based on the prerequisites and consequences of different types of attacks, the proposed approach correlates alerts by matching the consequence of some previous alerts and the prerequisite of some later ones with OS-level logs. As a result, the accuracy of the proposed method and its advantage demonstrated to focus on building IDS alert correlation with OS-level logs in information security systems.Master Thesis A Firewall Design for Academic Environments(Izmir Institute of Technology, 2001) Tok, Metin; Koltuksuz, Ahmet HasanComputer networks in academic environments could have many secUlity problems if there weren't enough precaution. The source of these problems is generally vulnerabilities of TCP/IP protocol and Internet. Vulnerabilities can cause threats. These threats will be analyzed in this thesis. There are many kind of countelmeasures to prevent the assets of the academic networks. Firewalls are a kind of countermeasure against these attacks. In this thesis, these countelmeasures will be also analyzed and a firewall will be designed and proposed for academic environments against these threats.Master Thesis Time synchronization in wireless sensor metworks(Izmir Institute of Technology, 2008) Kulaklı, Ali Burak; Aytaç, İsmail SıtkıIn this thesis, an enhanced synchronization algorithm for Wireless Sensor Networks is proposed. This algorithm uses TPSN (Timing-sync protocol for sensor networks) as a base synchronizer and does modifications on it to achieve a better synchronization with a lower message overhead. Basically, there are three improvements that can be applied onto TPSN, which are clustering the network, chain synchronization among nodes and adaptive synchronization interval. In the first phase of the thesis, a simulation environment is provided for TPSN using pthreads on a Linux computer. This environment helps understanding the parameters that TPSN relies on and testing the algorithm in different simulated environments with different characteristics using the enhancements onto TPSN algorithm. In the second phase, ns2 simulator environment is used to get more precise results and test the modifications. Finally, latest modifications are done on TPSN and all the results are gathered from ns2.Master Thesis Access Monitoring System for Distributed Firewall Policies(Izmir Institute of Technology, 2008) Çakı, Oğuzhan; Tuğlular, TuğkanInternet has provided several benefits in terms of information sharing. However, Internet is an insecure environment that can cause threats to private networks. As a result, network security becomes a critical issue. One of the important tools used in network security is firewall. Firewalls protect a private network from external threats by restricting network traffic according to predefined security rules. Basically, firewalls apply these rules to each packet that passes over them. Distributed firewalls are a new approach to firewall to overcome some drawbacks of traditional firewalls. Distributed firewall design is based on the idea of enforcing the policy rules at the endpoints rather than a single entry point to network. Management of policy rules is a critical issue in both traditional and distributed firewalls. We propose a monitoring application for distributed firewall policies to keep track of actions (create, read. update, delete) performed on policy rule set. The resulting data produced by the monitoring application will be very helpful in policy management process.Master Thesis Business Activity Monitoring for Logistics Management Systems(Izmir Institute of Technology, 2013) Titiz, Dilek; Ayav, TolgaEnterprises use different software for different purposes, such as accounting management, customer relationships, so that information technologies become an integral part of business processes. A business process turns out to be a combination of these different software, besides the received information/data by one of software tools that comes from another one. Different software systems cannot have been aware of each other directly. When the domain under consideration is container logistics, in addition to the different software, there are many relationships with other companies and so there are many different systems, variable types and file types that are being used. There are different transportation modes like highway, marine or airway, and by the expansion of intermodal transportation, tracking data is getting harder. For container logistics being a complicated business, tracking data is a necessity. The necessity is to track and to control the data that comes from outer systems and inner systems to an interoperable platform. This necessity enables trackable business processes and thus increases the business performance. In the scope of this thesis, a business activity monitoring environment is created in case of ARKAS Holding, which works on container logistics domain and Bimar Inc., which is the software provider of it. As it was mentioned above, this tracking needs cause to creation of the proposed and implemented monitoring environment for such a case of ARKAS Holding that does intermodal transportation, which has many endpoints in its business processes and there are too many data to be tracked. There are many different endpoints, such as marine, roadway and depot, in container logistics; also there are many different data types that are coming from different systems. Thus, the ‘Business Activity Monitoring’ environment is created as this thesis’ subject to make these different systems talk to each other, also to enable gathering data directly and automatically to achieve real-time monitoring.Master Thesis Distinct Encoded Records Join Operator for Distributed Query Processing(Izmir Institute of Technology, 2012) Öztürk, Ahmet Cumhur; Ergenç, BelginNowadays distributing data among different locations is very popular due to needs of business environment. In today's business environment, accessible, reliable, and scalable data is a critical need and distributed database system provides those advantages. It is a need to transfer data between sites while processing query in distributed database system, if the connection speed between sites is low then transmitting data is very time consuming. Optimizing distributed query processing is different from optimizing query processing in local database system. Most of the algorithms generated for distributed query processing focus on reducing the amount of data transferred between sites. Join operation in database system is for combining different tables with a common join attribute value, if the tables that are put in a join operation are at different locations then some of the tables are needed to be transferred to between sites. Join operation optimization algorithms in distributed database system focus on reducing the amount of data transfer by eliminating redundant tuples from relation before transmitting it to the other site. This thesis introduces a new distributed query processing technique named distinct encoded records join operation (DERjoin) which considers duplicated join attributes in a relation and eliminates them before sending the relation to another site.Master Thesis Designing Programmable Logic Controller for Data Acquisition and Control(Izmir Institute of Technology, 2010) Gözütok, Mehmet Emre; Ayav, Tolgain this study, a new dsPIC microcontroller based PLC design for requirements of data acquisition, signal processing and control applications has been discussed. The aim of the study was to realize of today's automation applications with a more economic, convenient, and functional device other than PLC applications. This device is a general purpose product available in ali areas. it is used to determine the city power grid harmonics. The circuit schema of the device is drawn in Multisim environment. The design of the printed circuit board is implemented in Ultiboard. The Microchip IDE is used for writing the codes and programming the MCU. The C30 compiler is used for compiling the codes which is distributed free of charge by Microchip. To evaluate the performance of the product, the harmonics in the electricity netvvork are tested. The operating time of the two main functions which are used in the FFT algorithm that was used for determining those harmonics were observed and results were expressed visually. Further development that could be done, by other researchers, in the future, is also discussed in the final chapter.Master Thesis A Cluster Based Communication Architecture for Distributed Applications in Mobile Ad Hoc Networks(Izmir Institute of Technology, 2006) Dağdeviren, Orhan; Erciyes, KayhanIn this thesis, we aim to design and implement three protocols on a hierarchical architecture to solve the balanced clustering, backbone formation and distributed mutual exclusion problems for mobile ad hoc network(MANET)s. Our ¯rst goal is to cluster the MANET into balanced partitions. Clustering is a widely used approach to ease implemen-tation of various problems such as routing and resource management in MANETs. We propose the Merging Clustering Algorithm(MCA) for clustering in MANETs that merges clusters to form higher level of clusters by increasing their levels. Secondly, we aim to con-struct a directed ring topology across clusterheads which were selected by MCA. Lastly, we implement the distributed mutual exclusion algorithm based on Ricart-Agrawala algo-rithm for MANETs(Mobile RA). Each cluster is represented by a coordinator node on the ring which implements distributed mutual exclusion algorithm on behalf of any member in the cluster it represents. We show the operations of the algorithms, analyze their time and message complexities and provide results in the simulation environment of ns2.