Computer Sciences Commons^™

Gnss Augmentation Through Ku-Band Communication Satellites With Rtkrealization, Şenol Gülgönül

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a method to broadcast real-time kinematics (RTK) corrections over a communication satellite is proposed. RTK corrections generated by the reference station are uplinked to the communication satellite within a multiplexed DVB-S carrier. Corrections are received by a satellite dish and the DVB-S satellite receiver. Better than 18 cm of accuracy is achieved for rover distances of up to 500 km in Turkey. The proposed method can be used as an alternative satellite-based augmentation system for Turkey and other countries.

A Strategy For Improving Netclust Server Placement For Multicloud Environments, Yuting Zhao, Jinhong Liu, Qing Fang, Lifang Xu, Changlai Du, Yuan Xiaoqun

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we propose a fast server placement algorithm to improve the NetClust framework and make it more efficient and exible. To this end, we introduce hierarchical clustering technologies to the NetClust framework and propose a exible server placement algorithm, which integrates the agglomerative and divisive clustering technologies to reduce the time complexity and avoid the performance uctuation affected by the initial node selection. The experiment results show that our server placement algorithm may reduce the time complexity of server selection of NetClust significantly and improve the exibility and applicability of the NetClust.

Performance Analysis Of Hamming Code For Wsn-Based Smart Grid Applications, Meli̇ke Yi̇ği̇t, Vehbi̇ Çağri Güngör, Pinar Bölük

Turkish Journal of Electrical Engineering and Computer Sciences

Many methods have been employed to detect, compare, and correct errors to increase communication reliability and efficiency in wireless sensor networks (WSNs). However, to the best of our knowledge, no existing study has compared the performance of error control codes by using different modulation techniques in a smart grid communication environment when multichannel scheduling is used. This paper presents a detailed performance evaluation and makes a comparison of different modulation techniques, such as frequency shift keying (FSK), differential phase shift keying (DPSK), binary phase shift keying (BPSK), and offset quadrature phase-shift keying (OQPSK), using Hamming codes in a 500-kV line-of-sight …

An Optimized Multiobjective Cpu Job Scheduling Using Evolutionary Algorithms, Santhi Venkatraman, Dharshikha Selvagopal

Turkish Journal of Electrical Engineering and Computer Sciences

Scheduling in a multiprocessor parallel computing environment is an NP-hard optimization problem. The main objective of this work is to obtain a schedule in a distributed computing system (DCS) environment that minimizes the makespan and maximizes the throughput. We study the use of two of the evolutionary swarm optimization techniques, the firefly algorithm and the artificial bee colony (ABC) algorithm, to optimize the scheduling in a DCS. We also enhance the traditional ABC algorithm by merging the genetic algorithm techniques of crossover and mutation with the employed bee phase and the onlooker phase, respectively. The resulting enhanced ABC algorithm is …

A New Method Based On Pixel Density In Salt And Pepper Noise Removal, Uğur Erkan, Levent Gökrem

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we deliver a new method to remove salt and pepper noise, which we refer to as based on pixel density filter (BPDF). The first step of the method is to determine whether or not a pixel is noisy, and then we decide on an adaptive window size that accepts the noisy pixel as the center. The most repetitive noiseless pixel value within the window is set as the new pixel value. By using 18 test images, we give the results of peak signal-to-noise ratio (PSNR), structural similarity (SSIM), image enhancement factor (IEF), standard median filter (SMF), adaptive …

Blood Glucose Control Using An Abc Algorithm-Based Fuzzy-Pid Controller, Seli̇m Soylu, Kenan Danişman

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a Mamdani-type fuzzy controller is proposed as the controller part of an artificial pancreas. The controller is optimized with the artificial bee colony optimization algorithm. The glucose{insulin regulatory system, based on a nonlinear differential model in the presence of delay, is used both for virtual patient and healthy person data. The main target of the controller is to mimic a blood glucose concentration profile of the healthy person with exogenous insulin infusion. Simulations are performed to assess the control function in terms of tracking the blood glucose concentration profile of the healthy person and minimizing errors. To …

An Efficient Algorithm To Decompose A Compound Rectilinear Shape Into Simplerectilinear Shapes, Imran Sharif, Debasis Chaudhuri, Naveen Kushwaha, Ashok Samal, Brij Mohan Singh

Turkish Journal of Electrical Engineering and Computer Sciences

Detection of a compound object is a critical problem in target recognition. For example, buildings form an important class of shapes whose recognition is important in many remote sensing based applications. Due to the coarse resolution of imaging sensors, adjacent buildings in the scenes appear as a single compound shape object. These compound objects can be represented as the union of a set of disjoint rectilinear shaped objects. Separating the individual buildings from the resulting compound objects in a segmented image is often difficult but important nevertheless. In this paper we propose a new and efficient technique to decompose a …

Signal Processing In Recursive Rejection Filters In The Transient Mode, Dmitrii Popov, Sergey Smolskiy

Turkish Journal of Electrical Engineering and Computer Sciences

A recursive rejection filter (REF) oriented to the radar signal extraction from the moving targets on a background of passive interference in the form of undesired re ections from fixed or slowly moving objects (so-called clutter) is the object under investigation. By means of the state variable method, which gives the adequate filter description in the time domain, the REF structure in the transient mode is synthesized, which is improved with the aim of transient acceleration with the clutter edge arriving. The REF structure's improvement in the transient mode is achieved by its reconfiguration, which is made by REF output …

Last Level Cache Partitioning Via Multiverse Thread Classification, Burak Sezi̇n Ovant, İsa Ahmet Güney, Muhammed Emi̇n Savaş, Gürhan Küçük

Turkish Journal of Electrical Engineering and Computer Sciences

Last level caches (LLCs) are part of the last line of defense against the famous memory wall problem. Today, almost all processors utilize a LLC for the same reason. This study extends our previous work, which proposed a cache-partitioning mechanism using thread classification. Here, we propose three enhancements to the existing system: 1) an adaptive traffic threshold mechanism for more portable classification hardware, 2) a new method for classifying way-hungry threads, and finally, 3) a thorough comparison of two design alternatives. Compared to the original way- partitioning mechanism, we show that the proposed mechanism's performance improved by around 6%, on …

Weighted Intensity Hue Saturation Transform For Image Enhancement Andpansharpening, Nur Hüseyi̇n Kaplan

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a weighted intensity hue saturation transform (WIHS) is proposed for image enhancement and pansharpening. The proposed transform obtains the intensity component of the classical intensity hue saturation (IHS) transform, by weighting the bands (red, green, and blue) of the image, whereas the hue and saturation components remain unchanged. The weight for each band is determined according to the brightness interval of the corresponding band and its standard deviation. The purpose of obtaining the intensity component by weighting is to keep more information from the bands of the input image. The classical intensity component used in image processing …

Novel Representations For A Coherent Threshold Reliability System: A Tale Of Eightsignal Ow Graphs, Ali Muhammad Rushdi, Alaa Mohammad Alturki

Turkish Journal of Electrical Engineering and Computer Sciences

A threshold system is a reliability system whose success/failure is a threshold switching function in the successes/failures of its components. A coherent system (CS) is one that is causal, monotone, and with relevant components. The coherent threshold system (CTS), typically called the weighted k-out-of-n system, is consequently described by strictly positive weights and threshold. This paper presents recursive relations as well as boundary conditions for eight entities pertaining to a CTS. These are (a) expressions of monoform literals as well as disjoint or probability- ready expressions for either system success or failure, and (b) all-additive formulas as well as inclusion-exclusion …

การจำแนกโครงสร้างจุลภาคไทเทเนียมด้วยโครงข่ายประสาทคอนโวลูชันเต็มรูป, สิโรดม มงคลธนาภรณ์

Chulalongkorn University Theses and Dissertations (Chula ETD)

ในช่วงทศวรรษที่ผ่านมา ได้มีการใช้การเรียนรู้เชิงลึกอย่างแพร่หลายเพื่อจำแนกภาพที่ให้ความแม่นยำสูง การแบ่งส่วนความหมายเป็นประเภทหนึ่งของการเรียนรู้เชิงลึกที่มุ่งเน้นการจำแนกคลาสในแต่ละพิกเซลของภาพ ทางด้านโลหะศาสตร์ ไทเทเนียมและอัลลอยมีคุณสมบัติที่โดดเด่นสำหรับการใช้งานทางชีวการแพทย์ โดยเฉพาะในการผ่าตัดฝังวัสดุทดแทน การตรวจสอบวัสดุโดยทั่วไปมักกระทำโดยผู้เชี่ยวชาญในการจำแนกโครงสร้างจุลภาคไทเทเนียม งานวิจัยนี้เสนอการประยุกต์ใช้เทคนิคการเรียนรู้เชิงลึกเพื่อเป็นแนวทางการจำแนกระดับพิกเซลโครงสร้างจุลภาคไทเทเนียมที่อาจช่วยลดทรัพยากรและความไม่แน่นอนระหว่างการควบคุมคุณภาพ วิธีการที่ใช้คือเทคนิคการแบ่งส่วนความหมายที่เรียกว่า โครงข่ายประสาทคอนโวลูชันเต็มรูปที่ถูกพัฒนาด้วยสถาปัตยกรรมยู-เน็ต งานวิจัยนี้ได้สำรวจการบูรณาการเทคนิคการปรับจูนเข้ากับสถาปัตยกรรมยู-เน็ตเพื่อปรับปรุงสมรรถนะแบบจำลอง โมเดลที่สร้างขึ้นถูกปรับจูนด้วยค่าน้ำหนักที่เรียนรู้มาแล้วก่อนหน้าจากตัวจำแนกวีจีจี-16 นอกจากนี้ ชุดข้อมูลภาพโครงสร้างจุลภาคไทเทเนียมได้ถูกเพิ่มจำนวนตัวอย่างด้วยวิธีความผิดปกติยืดหยุ่น สำหรับการประเมินสมรรถนะแบบจำลองจะใช้ตัววัด 4 ตัว ประกอบด้วย ความแม่นยำพิกเซล ความแม่นยำเฉลี่ย ไอโอยูเฉลี่ย และ ไอโอยูถ่วงน้ำหนักความถี่ ผลลัพธ์การประเมินพบว่าค่าความแม่นยำเพิ่มขึ้นเล็กน้อย ในขณะที่เวลาเรียนรู้เร็วกว่ามากเทียบกับการเรียนรู้ปกติที่ไม่มีการปรับจูนค่าน้ำหนักเริ่มต้น

Boundwarden: Thread-Enforced Spatial Memory Safety Through Compile-Time Transformations, Smith Dhumbumroong

Chulalongkorn University Theses and Dissertations (Chula ETD)

This dissertation presents BoundWarden, a novel runtime spatial memory safety enforcement technique that comprehensively detects and prevents buffer overflow and other out-of-bound errors in buffers on stack, heap, and BSS and data segments of memory. BoundWarden leverages the ubiquity of multi-core processors by offloading most of the works to a dedicated bound checking thread, which performs bound checking and manages metadata, thus reducing the runtime overhead. Since BoundWarden stores base and bound of buffers in a dedicated bound table, the memory layout of programs remains unchanged, thus preserving compatibility with existing libraries and binaries. Experiments showed that the prototype of …

A Security Review Of Local Government Using Nist Csf: A Case Study, Ahmed Ibrahim, Craig Valli, Ian Mcateer, Junaid Chaudhry

Research outputs 2014 to 2021

Evaluating cyber security risk is a challenging task regardless of an organisation’s nature of business or size, however, an essential activity. This paper uses the National Institute of Standards and Technology (NIST) cyber security framework (CSF) to assess the cyber security posture of a local government organisation in Western Australia. Our approach enabled the quantification of risks for specific NIST CSF core functions and respective categories and allowed making recommendations to address the gaps discovered to attain the desired level of compliance. This has led the organisation to strategically target areas related to their people, processes, and technologies, thus mitigating …

A Stochastic Petri Net Reverse Engineering Methodology For Deep Understanding Of Technical Documents, Giorgia Rematska

Browse all Theses and Dissertations

Systems Reverse Engineering has gained great attention over time and is associated with numerous different research areas. The importance of this research derives from several technological necessities. Security analysis and learning purposes are two of them and can greatly benefit from reverse engineering. More specifically, reverse engineering of technical documents for deeper automatic understanding is a research area where reverse engineering can contribute a lot. In this PhD dissertation we develop a novel reverse engineering methodology for deep understanding of architectural description of digital hardware systems that appear in technical documents. Initially, we offer a survey on reverse engineering of …

Building An Abstract-Syntax-Tree-Oriented Symbolic Execution Engine For Php Programs, Jin Huang

Browse all Theses and Dissertations

This thesis presents the design, implementation, and evaluation of an abstract-syntax-tree-oriented symbolic execution engine for the PHP programming language. As a symbolic execution engine, our system emulate the execution of a PHP program by assuming that all inputs are with symbolic rather than concrete values. While our system inherits the basic definition of symbolic execution, it fundamentally differs from existing symbolic execution implementations that mainly leverage intermediate representation (IRs) to operate. Specifically, our system directly takes the abstract syntax tree (AST) of a program as input and subsequently interprets this AST. Performing symbolic execution using AST offers unique advantages. First, …

Slim Embedding Layers For Recurrent Neural Language Models, Zhongliang Li

Browse all Theses and Dissertations

Recurrent neural language (RNN) models are the state-of-the-art method for language modeling. When the vocabulary size is large, the space taken to store the model parameters becomes the bottleneck for the use of these type of models. We introduce a simple space compression method that stochastically shares the structured parameters at both the input and output embedding layers of RNN models to significantly reduce the size of model parameters, but still compactly represents the original input and the output embedding layers. The method is easy to implement and tune. Experiments on several data sets show that the new method achieves …

A Reliable Data Provenance And Privacy Preservation Architecture For Business-Driven Cyber-Physical Systems Using Blockchain, Xueping Liang, Sachin Shetty, Deepak K. Tosh, Juan Zhao, Danyi Li, Jihong Liu

VMASC Publications

Cyber-physical systems (CPS) including power systems, transportation, industrial control systems, etc. support both advanced control and communications among system components. Frequent data operations could introduce random failures and malicious attacks or even bring down the whole system. The dependency on a central authority increases the risk of single point of failure. To establish an immutable data provenance scheme for CPS, the authors adopt blockchain and propose a decentralized architecture to assure data integrity. In business-driven CPS, end users are required to share their personal information with multiple third parties. To prevent data leakage and preserve user privacy, the authors isolate …

Fundamentals Of Neutrosophic Logic And Sets And Their Role In Artificial Intelligence (Fundamentos De La Lógica Y Los Conjuntos Neutrosóficos Y Su Papel En La Inteligencia Artificial ), Florentin Smarandache, Maykel Leyva-Vazquez

Branch Mathematics and Statistics Faculty and Staff Publications

Neutrosophy is a new branch of philosophy which studies the origin, nature and scope of neutralities. This has formed the basis for a series of mathematical theories that generalize the classical and fuzzy theories such as the neutrosophic sets and the neutrosophic logic. In the paper, the fundamental concepts related to neutrosophy and its antecedents are presented. Additionally, fundamental concepts of artificial intelligence will be defined and how neutrosophy has come to strengthen this discipline.

Resource Optimization In Wireless Sensor Networks For An Improved Field Coverage And Cooperative Target Tracking, Husam Sweidan

Dissertations, Master's Theses and Master's Reports

There are various challenges that face a wireless sensor network (WSN) that mainly originate from the limited resources a sensor node usually has. A sensor node often relies on a battery as a power supply which, due to its limited capacity, tends to shorten the life-time of the node and the network as a whole. Other challenges arise from the limited capabilities of the sensors/actuators a node is equipped with, leading to complication like a poor coverage of the event, or limited mobility in the environment. This dissertation deals with the coverage problem as well as the limited power and …

Implementing Write Compression In Flash Memory Using Zeckendorf Two-Round Rewriting Codes, Vincent T. Druschke

Dissertations, Master's Theses and Master's Reports

Flash memory has become increasingly popular as the underlying storage technology for high-performance nonvolatile storage devices. However, while flash offers several benefits over alternative storage media, a number of limitations still exist within the current technology. One such limitation is that programming (altering a bit from its default value) and erasing (returning a bit to its default value) are asymmetric operations in flash memory devices: a flash memory can be programmed arbitrarily, but can only be erased in relatively large batches of storage bits called blocks, with block sizes ranging from 512K up to several megabytes. This creates a situation …

Hardware Implementation And Comparison Of Displacement Retrieval Algorithms For A Laser Diode-Based Optical Feedback Interferometric Sensor, Ghazi Rehman, Usman Zabit, Muhammad Obaid Ullah

Turkish Journal of Electrical Engineering and Computer Sciences

Optical feedback interferometer (OFI) lasers, also called self-mixing (SM) lasers, have been widely explored over the last couple of decades due to their low cost, compactness, and self-aligned nature and they provide a very good solution for measurements of displacement, vibration, distance, velocity, etc. The SM effect takes place when a part of the laser beam is fed back to the active laser cavity after reflecting from the target. The reflected beam interferes with the emitted beam and hence the optical and spectral characteristics of the laser get changed. To retrieve the vibration or displacement signal of the target from …

Field-Verified Integrated Eaf-Svc-Electrode Positioning Model Simulation And Anovel Hybrid Series Compensation Control For Eaf, Ahmed Hassan, Amr Abou-Ghazala, Ashraf Megahed

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, modeling and simulation of a typical steel-making network are realized using MATLAB Simulink environment and validated using trends collected from an actual steel plant. The models integrate different reactions between an electric arc furnace (EAF), a static Var compensator, and electrode positioning systems according to a previously introduced theory of operations. In addition, the conventional electrode positioning control performance is compared with the new hybrid series compensation control method to demonstrate the superiority of the new method regarding system response. With help of the proposed series compensation, the reference resistance value was restored 2.5 s faster than …

A Novel Efficient Tsv Built-In Test For Stacked 3d Ics, Badi Guibane, Belgacem Hamdi, Brahim Ben Salem, Abdellatif Mtibaa

Turkish Journal of Electrical Engineering and Computer Sciences

A through-silicon via (TSV) is established as the main enabler for a three-dimensional integrated circuit (3D IC) that increases system density and compactness. The exponential increase in TSV density led to TSV-induced catastrophic and parametric faults. We propose an original architecture that detects errors caused by TSV manufacturing defects. The proposed design for testability is a built-in technique that detects errors in an early manufacturing stage and is hence very economically attractive. The proposal is capable of testing each and every TSV in the network. The technique achieves high fault coverage and high observability.

“Woodlands” - A Virtual Reality Serious Game Supporting Learning Of Practical Road Safety Skills., Krzysztof Szczurowski, Matt Smith

Conference Papers

In developed societies road safety skills are taught early and often practiced under the supervision of a parent, providing children with a combination of theoretical and practical knowledge. At some point children will attempt to cross a road unsupervised, at that point in time their safety depends on the effectiveness of their road safety education. To date, various attempts to supplement road safety education with technology were made. Most common approach focus on addressing declarative knowledge, by delivering road safety theory in an engaging fashion. Apart from expanding on text based resources to include instructional videos and animations, some stakeholders …

User-Friendly Deniable Storage For Mobile Devices, Bing Chang, Yao Cheng, Bo Chen, Fengwei Zhang, Wen-Tao Zhu, Yanju Liu, Zhan Wang

Research Collection School Of Computing and Information Systems

Mobile devices are prevalently used to process sensitive data, but traditional encryption may not work when an adversary is able to coerce the device owners to disclose the encryption keys. Plausibly Deniable Encryption (PDE) is thus designed to protect sensitive data against this powerful adversary. In this paper, we present MobiPluto, a user-friendly PDE scheme for denying the existence of sensitive data stored on mobile devices. A salient difference between MobiPluto and the existing PDE systems is that any block-based file systems can be deployed on top of it. To further improve usability and deniability of MobiPluto, we introduce a …

Integrated Reward Scheme And Surge Pricing In A Ride Sourcing Market, Hai Yang, Chaoyi Shao, Hai Wang, Jieping Ye

Research Collection School Of Computing and Information Systems

Surge pricing is commonly used in on-demand ride-sourcing platforms (e.g., Uber, Lyft and Didi) to dynamically balance demand and supply. However, since the price for ride service cannot be unlimited, there is usually a reasonable or legitimate range of prices in practice. Such a constrained surge pricing strategy fails to balance demand and supply in certain cases, e.g., even adopting the maximum allowed price cannot reduce the demand to an affordable level during peak hours. In addition, the practice of surge pricing is controversial and has stimulated long debate regarding its pros and cons. In this paper, to address the …

การปรับปรุงการแยกฉากหลังบนพื้นหลังสีเขียวไม่สม่ำเสมอแบบทันที, วรายุ จริยาวัฒนรัตน์

Chulalongkorn University Theses and Dissertations (Chula ETD)

วัตถุประสงค์หลักของงานวิจัยนี้คือปรับปรุงการแยกฉากหลังบนพื้นหลังสีเขียวที่ไม่สม่ำเสมอแบบทันที ในวิธีการพื้นฐาน แต่ละพิกเซลจะถูกคำนวณว่าเป็นฉากหลังโดยใช้ค่าขีดจำกัดเดียวกันทั้งภาพเพียง 2 ค่า แต่ในความเป็นจริง วิธีการนี้มีปัญหาในหลาย ๆ กรณี เช่น พื้นหลังไม่ได้เป็นสีเดียวกันทั้งหมด หรือมีเงาของนักแสดงทอดลงไปที่พื้นหลัง เป็นต้น ดังนั้นการใช้ค่าขีดจำกัดเดียวกันหมดทั้งภาพจึงไม่เหมาะสมสำหรับกรณีดังกล่าว งานวิจัยนี้จึงใช้การประมาณความหนาแน่นเคอร์เนลมาช่วยในการหาค่าขีดจำกัดของแต่ละพิกเซลในภาพ เพื่อให้ทุก ๆ พิกเซลในภาพมีขีดจำกัดที่เหมาะสม และยังมีความเร็วในการประมวลผลที่สามารถออกอากาศสดได้ที่ 60 เฟรมต่อวินาที สำหรับความละเอียดระดับ Full HD

Automated Optical Mark Recognition Scoring System For Multiple-Choice Questions, Murtadha Alomran

Theses: Doctorates and Masters

Multiple-choice questions are one of the questions commonly used in assessments. It is widely used because this type of examination can be an effective and reliable way to examine the level of student’s knowledge. So far, this type of examination can either be marked by hand or with specialised answer sheets and scanning equipment. There are specialised answer sheets and scanning equipment to mark multiple-choice questions automatically. However, these are expensive, specialised and restrictive answer sheets and optical mark recognition scanners.

This research aims to design and implement a multiple-choice answer sheet and a reliable image processing-based scoring system that …

ระบบนำทางหุ่นยนต์ด้วยหลายตัวนำทางย่อยและหลายแผนที่ย่อย, สุขุม สัตตรัตนามัย

Chulalongkorn University Theses and Dissertations (Chula ETD)

การใช้งานหุ่นยนต์อัตโนมัติในเขตเมืองที่มีความหลากหลายของลักษณะพื้นที่สูงเป็นงานท้าทายที่ต้องการโปรแกรมนำทางและรูปแบบแผนที่ที่แตกต่างกันในแต่ละบริเวณ การปฏิบัติงานของหุ่นยนต์ในโลกจริงต้องเจอกับสิ่งแวดล้อมที่มีการเปลี่ยนแปลงอย่างต่อเนื่อง เช่น ฝนตกหรือความคับคั่งของบริเวณที่ต้องนำทาง ส่งผลให้ต้องปรับแผนเส้นทาง ในงานวิจัยนี้นำเสนอระบบนำทางหุ่นยนต์ในโลกจริงซึ่งเป็นรูปแบบใหม่ของการสลับการทำงานระหว่างโปรแกรมนำทางหลายตัวอย่างเหมาะสม เพื่อให้สามารถจัดการกับพฤติกรรมของหุ่นยนต์และสภาพแวดล้อมที่ท้าทายได้ ระบบที่นำเสนอในงานวิจัยนี้เป็นผลลัพธ์ของการติดตั้งหุ่นยนต์จริงในระบบซึ่งมีผู้ใช้งานและสภาพแวดล้อมจริง