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A web-based decision support system for class-teacher timetabling problem
No full textTezin basılısı İstanbul Şehir Üniversitesi Kütüphanesi'ndedir.Class-Teacher Timetabling Problem determines weekly timetables for class-teacher pair with respect to certain hard and soft constraints, and institutions’ specific constraints. Group balancing problem aims to create heterogeneous structure within the groups, and homogeneous structure between the groups. In this thesis, mathematical models are developed for class-teacher timetabling problem and group balancing problem frequently encountered during the planning of new semester in educational institutions. Additionally, a web-based decision support system (DSS) is designed for the related problems. As a contribution to this sub-field, this study provides tools to the planners to prepare weekly timetables and class lists in a short time.
A mixed-integer model is developed for group balancing problem, and aims to minimize deviationofaveragescoreofthegeneratedclassesfromthegeneralaverage, andtoensure balanced distribution of students among classes according to gender, international, and repeat status. A binary integer model proposed for class-teacher timetabling problem. This model is formulated as a constraint satisfaction problem with no objective function, but includes general timetabling constraints and specific constraints for the institution.
Many educational institutions still prepare timetables manually due to lack of general applicability of customized software. The end-user interface allows planners to use mathematical model instead of manually preparing weekly timetables and class lists. The exclusive contribution of this study is to design a DSS for the end user. The functions of this DSS include data entry, pre-processing of data, solving the problem, and reporting solution. DSS is based on PHP script, and GAMS is used to solve mathematical models.
The data from İstanbul Şehir University School of Languages English Preparatory Program (SEPP) is used as a case study to demonstrate operation of the system. Class lists and weekly timetables were successfully created within minutes instead of two days taken manually. SEPP approved the timetables and declared that our system satisfies their requests. Class lists and weekly timetables for Spring 2017 have been planned using our system.Declaration of Authorship ii
Abstract iii
Öz iv
Acknowledgments vi
List of Figures ix
List of Tables x
1 Introduction 1
2 Literature Review and Background 3
2.1 Course Timetabling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.2 Examination Timetabling . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.3 Class-Teacher Timetabling . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.4 Solution Approaches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.4.1 Mathematical Programming Based Approaches . . . . . . . . . . . 11
2.4.2 Graph Coloring Techniques . . . . . . . . . . . . . . . . . . . . . . 13
2.4.3 Heuristic Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2.5 Novelty and Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.5.1 Decision Support System . . . . . . . . . . . . . . . . . . . . . . . 16
3 Problem Description 21
3.1 Preparing Class Lists: Karmalama . . . . . . . . . . . . . . . . . . . . . . 27
3.2 Preparing Weekly Timetables: WeTiTa . . . . . . . . . . . . . . . . . . . . 33
4 Case Study 44
4.1 Preparing Class Lists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
4.2 Preparing Weekly Timetables . . . . . . . . . . . . . . . . . . . . . . . . . 48
5 Summary and Conclusions 52
A Karmalama: Results of Case Studies 54
B WeTiTa: Data of Case Study 64
C WeTiTa: Results of Case Study 71
Bibliography 8
Global carbon accounting tool (GCAT) for manufacturing supply chains:the world model
No full textThis research presents a global carbon accounting tool (GCAT) developed by the Sustainable Systems & Solutions Lab (S3-Lab) at Istanbul Sehir University, Turkey. This tool is able to capture the regional and global carbon footprints of manufacturing supply chains for world's 40 major economies. The GCAT will enable users to conduct carbon footprint analysis for the specific industry of selected country in 5 steps (http://s3-lab.sehir.edu.tr/gcat.html). The European food and drink industry will be chosen as a case study to conduct supply chain-based carbon footprint analyses including production versus consumption based analysis, sector breakdown for supply chain components, scope-based analysis and impact-by-country analysis for supply chain carbon emissions
Rightscope:detecting search campaingns positive and negativequeries
No full textIn search engine advertising, the right selection of keywords is one of the most important step to maximize the advertisers’ profitability. Keyword suggestion methodologies are used to map the advertisers selection of keywords and the recent popular queries using statistical data. In this project we are trying to classify the searchqueriesintorelevantandnon-relevant. Inotherwords,we are trying to exclude unprofitable queries from the search campaign. As a labeling methodology, we built a Binary Independence Model (BIM) using both statistical and machine learning approaches. The BIM was built by combining scores from three different models: the Relevance Status Value (RSV) of the ProbabilityRankingPrinciple(PRP)model,LogisticRegressionModel’sprobabilities,andaWeightedCostModel(WCM).Scalingthe queries relevance by the estimated cost by the WCM model relativelyscoresthequerieswithlowercostshigherranking
Diamond-shaped microstrip patch antenna with defected ground structure
No full textIn this study, a broadband microstrip diamond-shaped patch antenna is designed for broadband communication. The results are presented by simulating microstrip patch antenna at 3.675 GHz and 10.35 GHz frequencies. The antenna was simulated in the frequency range of 1-15 GHz. S11, the input reflection coefficient parameter has a value of -14.63 dB at the frequency of 3.675 GHz and -11.91 dB at the frequency of 10.35 GHz. The antenna gain of the designed antenna is 7.76 dB at the first resonance frequency (3.675 GHz) and 11.04 dB antenna gain at the other resonance frequency (10.35 GHz)
Kapalıçarşı’da zaman
No full textUnutma İstanbul projesinin bir parçası olarak İstanbul Şehir Üniversitesi ile Türkiye Turing ve Otomobil Kurumu (TURİNG) işbirliği kapsamında Cahide Kayış tarafından çekilmiştir.Unutma İstanbul projesi İstanbul Kalkınma Ajansı'nın 2016 yılı "Yenilikçi ve Yaratıcı İstanbul Mali Destek Programı" kapsamında desteklenmiştir. Proje No: TR10/16/YNY/010
A model for an optical ring microresonator towards nanoparticle detection
Get PDFHigh-Q optical resonators are very prominent bio-sensing technologies that confines light inside a microsize system. Due to their small size and dielectric fabrication materials, these systems can be integrated cost-effectively on integrated chips along with other optical and electrical components. Measurement of the resonance shift proceeded by the transmission spectrum enables observation of binding events in real time, and can also be used to characterize particle size and type. Combination of small size and high Q factor empowers these devices with excellent detection capability. In this thesis, an optical microring resonator has been developed through a multiphysics model using finite element method to solve the relevant equations. All the platform was built in COMSOL Multyphisics software tool. The general framework of this sensor is based on a laser light source, a straight-shape waveguide, a ring-based waveguide, and a photodector at the end of the straight waveguide. A communication laser was used to generate the light at a wavelength of 1.55 µm.
In this thesis, it is important to achieve single particle detection inside an aqueous environment since most of the clinical samples are water based. The exact position of the resonance wavelength is located and the transmission spectrum is recorded. A linear correlation between the red shift in the resonance wavelength and increase in the radius of the microring is observed. When the ring radius was increased, there was a resonance shift in the wavelength towards higher values. It was also found that a resonance shift for a value as small as 10 nm could be detected. The interaction between the resonator and nanoparticles is implemented in a unique way. This implementation is performed by modeling nanoparticles by a layer around the ring and then changing its thickness with the corresponding refraction index of analyzed nanoparticle. This will affect the resonance when it is compared to the resonator response without the layer. The resonance shift should be in a linear trend in order to be able to use as biodetection sensor. The interactionbetweenasingleparticleandthesensoritselfdeterminethesensingcapability within a rapid time. The detection of a mimicked titanium dioxide nanoparticle as well as protein biomolecule with an effective size starting from around 10 nm in diameter has been reported.CONTENTS:
Declaration of Authorship ii
Abstract iii
Öz iv
Acknowledgments vi
List of Figures ix
Abbreviations xi
Physical Constants xii
Symbols xiii
1 Introduction 1 1.1 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Basic sensing operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.3 Literature Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.4 Thesis Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2 Theoretical Fundamentals of Optical Dielectric Waveguides and Optical Microresonators 11 2.1 Reflection and Refraction of Plane Wave . . . . . . . . . . . . . . . . . . 11 2.1.1 Snell’s Law . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2.2 Reflection and transmission of s wave (Transverse Electrical wave) (TE) 13 2.3 Reflection and Transmission of p Wave (Transverse Magnetic Wave) (TE) 14 2.4 Reflectance and Transmittance . . . . . . . . . . . . . . . . . . . . . . . . 16 2.5 Optical Waveguides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 2.6 Theory of Optical Coupling . . . . . . . . . . . . . . . . . . . . . . . . . . 23 2.7 Theory of Optical Microresonators WGM . . . . . . . . . . . . . . . . . . 24 2.7.1 Parameters of Optical Resonators . . . . . . . . . . . . . . . . . . . 26 2.7.1.1 Quality Factor (Q) . . . . . . . . . . . . . . . . . . . . . . 26 2.7.1.2 Loss Mechanisms . . . . . . . . . . . . . . . . . . . . . . 27 2.7.1.3 Finesse(F) . . . . . . . . . . . . . . . . . . . . . . . . . . 28 2.7.1.4 Mode volume . . . . . . . . . . . . . . . . . . . . . . . . . 28 2.8 Theory of Ring Resonators . . . . . . . . . . . . . . . . . . . . . . . . . . 29
3 Results and Discussions 33 3.1 Nanoparticles Sensing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 3.2 Correlation between the Ring Radius Variation and Resonance Shift as Sensing Mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 3.3 Q factor, Transmittance as a Function of Distance Between the Waveguides, FSR and FDHW Parameters Optimization . . . . . . . . . . . . . 42 3.4 Size and Refractive Index Variation using The Effective Medium Approximations - Yamaguchi model . . . . . . . . . . . . . . . . . . . . . . . . . . 50
4 Conclusion and Future Work 60
Bibliography 6
Estimating the selectivity of SQL LIKE queries
No full textTezin basılısı İstanbul Şehir Üniversitesi Kütüphanesi'ndedir
Perspectives of methods of laser monitoring of atmosphere and sea surface
No full textLaser monitoring (remote sensing) may be considered as the science of collecting and interpreting information about the atmosphere, earth and sea using sensors on earth, on platforms in our atmosphere (airplanes, balloons) or in space (satellites) without being in direct physical contact with them. Remote sensing by LIDARs (Light Identification Detection and Ranging) has wide applications as technique to probe the Earth's atmosphere, ocean and land surfaces. LIDARs are widely used to get knowledge of spatial and temporal variations in meteorological quantities (e.g. temperature, humidity, clouds and aerosol properties) and to monitor the changes in these quantities on different timescales. Subject of the present work is quite wide. It is rather difficult to perform analysis and to provide full knowledge about existing information. In the present work, in addition to the literature data, the information will be provided also about aerosol "KA-09 LIDAR" developed at the Marmara Research Centre (MRC), Materials Institute (MI) of Turkish Scientific and Technological Research Council (TUBITAK) and also about "KA-14 LIDAR" developed at the National Aviation Academy (NAA), Scientific-Research Institute of Transport and Aviocosmic Problems (SRITAP) of Azerbaijan for remote sensing of contaminations on water surfaces taking place during oil-gas production. The main goal of this paper is to give students insight in different remote sensing instruments and techniques (including their perspectives) that are used for the derivation of meteorological quantities and obtaining the information about water surface
