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Automatic modulation classification based on kernel density estimation
No full textIn this paper, we propose an efficient automatic modulation classification (AMC) scheme for a group of narrowband and digitally modulated signals such as quadrature phase-shift keying (QPSK), 16-PSK, 64-PSK, 4-quadratic-amplitude modulation (QAM), 16-QAM, and 64-QAM. The classification was performed by analyzing the probability density distribution for the real and imaginary parts of the modulated signals. To simplify the complexity of the proposed approach, we performed the classification in two stages: first, we classified the modulation between QAM and PSK signaling, and then, we determined the M-ary order of the modulation by developing kernel density estimation, which is typically used in nonparametric methods for the estimation of the probability density function of a random variable with finite data samples. Simulations were carried out to evaluate the performance of the proposed scheme for flat channels. It is observed that this simple efficient technique can find applications in blind AMC, as the performance comparison with the state of the art is promising
Optimal any-angle pathfinding in practice
No full textAny-angle pathfinding is a fundamental problem in robotics and computer games. The goal is to find a shortest path between a pair of points on a grid map such that the path is not artificially constrained to the points of the grid. Prior research has focused on approximate online solutions. A number of exact methods exist but they all require super-linear space and pre-processing time. In this study, we describe Anya: a new and optimal any-angle pathfinding algorithm. Where other works find approximate any-angle paths by searching over individual points from the grid, Anya finds optimal paths by searching over sets of states represented as intervals. Each interval is identified on-thefly. From each interval Anya selects a single representative point that it uses to compute an admissible cost estimate for the entire set. Anya always returns an optimal path if one exists. Moreover it does so without any offline pre-processing or the introduction of additional memory overheads. In a range of empirical comparisons we show that Anya is competitive with several recent (sub-optimal) online and pre-processing based techniques and is up to an order of magnitude faster than the most common benchmark algorithm, a grid-based implementation of A*
The United Nations in statebuilding:a historical institutionalist perspective to the case of Kosovo
No full textTezin basılısı İstanbul Şehir Üniversitesi Kütüphanesi'ndedir.This thesis examines the role of United Nations (UN) in the peacebuilding process. This study argues the UN has success potential in peacebuilding, statebuilding in particular, rather than conflict prevention and peacemaking. The empirical base of the study is the Kosovo statebuilding process from 1999 to 2008. An in-depth analysis of institution building of Kosovo political institutions indicates the UN has the ability to create a new path for sustainable institutions that lead to sustainable peace in postwar countries. The UN should cooperate with local actors in order to construct the new path and continuously support them until they become mature. Once cooperation of the UN and locals sets the path for new institutions, they will continue on their established path more with each down on that path. Kosovo institutions illustrate maturity and development in their success level based on Huntington’s criteria for successful institutions.ABSTRACT ................................................................................................................ iv
ÖZ ................................................................................................................................ v
PREFACE ................................................................................................................... vi
LIST OF TABLES ...................................................................................................... ix
LIST OF FIGURES ..................................................................................................... x
LIST OF ABBREVATIONS ...................................................................................... xi
CHAPTERS 1. INTRODUCTION .................................................................................................. 1 1.1. Background of the Problem ............................................................................... 2 1.2.
Methods and Data .............................................................................................. 4 1.3.
Theory in a Nutshell .......................................................................................... 4 1.4.
Plan of the thesis ................................................................................................ 7 2.
THE PREREQUISITES OF SUCCESSFUL UN PEACEBUILDING: A THEORETICAL APPLICATION OF HISTORICAL INSTITUTIONALISM ON PEACEBUILDING RESEARCH ................................................................................ 8
2.1. Introduction ....................................................................................................... 8
2.2. Literature Review .............................................................................................. 9
2.3. Conceptualizing Conflict Prevention, Peacemaking, and Peacebuilding ........ 12
2.3.1. Conflict Prevention ................................................................................... 12
2.3.2 Peacemaking .............................................................................................. 13
2.3.3. Peacebuilding ............................................................................................ 14
2.4. A theory on the effectiveness of United Nations in peacebuilding ................. 15
2.4.1. Evolution of UN peace operations: the path towards peacebuilding ........ 15
2.4.2. Why institutions are important for sustainable peace? A Historical institutionalist perspective on the UN statebuilding ........................................... 20
2.5. Conclusion ....................................................................................................... 25
3. NEW BORN KOSOVO POLITICAL INSTITUTIONS ....................................... 26
3.1. Introduction ..................................................................................................... 26
3.2. Towards NATO peacemaking: a brief historical background of the Kosovo war .......................................................................................................................... 26
3.2.1. Rambouillet Accords ................................................................................ 28
3.3. The United Nations Interim Administration in Kosovo .................................. 28
3.3.1. A New Path for Kosovo: How has the UN built up state institutions? The initial steps from 1999 to 2001 ........................................................................... 30
3.3.2. The Kosovo Transitional Council ............................................................. 31
3.3.3. Joint Interim Administrative Structure ..................................................... 31
3.3.4. Process of Formation of a Provisional Self-Government ......................... 33
3.3.4.1. The First Post-War Elections in October 2000 (Municipal Elections) ......................................................................................................................... 33
3.3.4.2. Constitutional Framework .................................................................. 35
3.3.4.3. First General Elections ....................................................................... 38
3.4. Conclusion ....................................................................................................... 38 4.INSTITUTIONALIZATION OF KOSOVO POLITICAL INSTITUTIONS ........ 40
4.1. Introduction ..................................................................................................... 40
4.2. The Level of Institutionalization ..................................................................... 41
4.2.1. Institutional Adaptability .......................................................................... 41
4.2.2. Institutional Complexity ........................................................................... 43
4.2.3. Institutional Autonomy ............................................................................. 46
4.2.3.1. Local Ownership in Institution Building Process .............................. 48
4.2.3.2. The Transfer of Authority to the PISG .............................................. 48
4.2.3.2.1. OSCE: Capacity building on the way of self-sustaining institutions ................................................................................................... 50
4.2.3.4. Further competences with the Eide Report and the Ahtisaari Plan .... 51
4.2.4. Institutional Coherence ............................................................................. 55
4.3. The Scope of Support ...................................................................................... 56
4.3.1. Support level of political elites in Kosovo................................................ 57
4.3.2. Support level of public in Kosovo ............................................................ 58
4.4. Conclusion ....................................................................................................... 61
5. CONCLUDING REMARKS ................................................................................. 63
5.1. Limitations of the Dissertation and Recommendations for Future Research .. 67
BIBLIOGRAPHY ...................................................................................................... 68
APPENDIX ............................................................................................................... 7
Aggressive test cost reductions through
No full textThe inclusion of various new test types in production test suites with the hope of keeping defect escape level in check continuously increases the test cost while the economics of the intensely competitive consumer marketplace dictates test strategies that are low cost yet still effective in defect detection. An adaptive test methodology is proposed in this paper to address the simultaneous demand for efficiency and effectiveness in testing through an adaptive prioritization of test vectors according to defect detection effectiveness, subsequently, leading to the identification of a compact yet effective test set. Experimental results confirm the effectiveness of the vector prioritization process and show substantial cost reduction levels
Small delay defect diagnosis through failure observation ordering
No full textRapidly increasing the yield for new process generations is crucial in achieving aggressive time-to-market requirements in semiconductor industry. As process scaling continues, subtle defects, primarily small delay defects that alter the timing of the circuits, are becoming increasingly common. An accurate diagnosis of small delay defects is essential in the identification of the cause of the defects and in the subsequent yield improvement. However, small and variable magnitude of small delay defects when coupled with the variable timing margins of the chips due to the process variation imposes inordinate challenges in small delay defect diagnosis. An approach for accurate small delay defect diagnosis that effectively prunes the candidate fault list based on the expected ordering of failure observation on outputs is proposed in this work
The writing subjects:Halide Edip and Assia Djebar
No full textDespite their physical distance from each other in terms of time and place, the Turkish Halide Edip (1882–1964) and the Algerian Assia Djebar (1936–2015) wrote in surprisingly similar ways. They share a multicultural and multilingual education andposition as writing subjects. As Muslimwomen writers in the modern literaryworld,theytraversepolitical,literary,andlinguisticborders.Thisessayexplores theirautobiographicalwritings,Djebar’sFantasia(1993)andEdip’sMemoirs(Adıvar 2004),where they contest colonialism, nationalism, and patriarchy. Who is the Muslim woman writer? The last few decades have witnessed a number of invaluable studies that examine the question, working mainly in a framework of ethnic, national, and linguistic origins (see Badran and cooke 2004; Brookshaw 2013; cooke 2001; Fernea and Bezirgan 1977; Havlioğlu 2010; MaltiDouglas1991;Mehta2014).AsforDjebar,therehasbeenmuchthought-provoking research on her writings in thecontext of postcolonial literature.1 Studies on Edip, on the contrary, have remained in the domain of national literature, and she is typicallyreadinthecontextofTurkishliterature.2ThisessayreadsDjebarandEdip through their Islamicate aesthetic heritages to examine how they challenge orientalist discourse and local patriarchies
Multilingual distributed word representation using deeplearning
No full textTezin basılısı, İstanbul Şehir Üniversitesi Kütüphanesi'ndedir.In this work, the problem of extracting meaningful multilingual word embeddings is studied with special focus on morphologically-rich languages. In order to achieve multilingualism, a data-driven method that makes use of a sentence-aligned parallel corpus is used. This method is expanded hierarchically to take account for the words parts, tokens or morphemes, rather than just considering the raw words as the basic language units. Also various architectures and aggregation functions for constructing word and sentences embeddings given their parts are studied and compared. The aggregation function for a speci c function is chosen according to the nature of the particular language. To evaluate the di erent methods, one sanity check test is used and two more tests are used to evaluate the quality of the resulting representations. The sanity check which is mainly used to make sure that the models are learning anything from the corpus and is also used for the parameter tuning, is the paraphrase test. The second test, t-SNE, is a visual test that just gives insights about the model's ability to bring semantically equivalent words and sentences close to each other in the space. The third test, that gives the most meaningful measure, is the cross-lingual document classi cation task. The (CLDC) task is concerned with training a supervised classi er using documents from one language, the rich-resources language, and testing it using another language, the low-resources one, while maintaining a satisfying performance. The performances of the models are described in terms of the F1-score. As the experiments have shown, a multilingual framework for extracting word-embeddings jointly for both English and Turkish that uses additive functions at both sentences and words level results the best result in terms of the F1-score achieved in the (CLDC) task. Various data preprocessing methods are also studied, the words can be either extracted by simply dividing the sentences using the space as a delimiter, using a tokenizer, or using a morphological analyzer in the case of the morphologically-rich languages. The experiments showed that using the raw data format for English and the morphemes as the basic language unit for Turkish yields the best results.Abstract iv
Öz v
Acknowledgments vii
List of Figures x
List of Tables xii
1 Background 1 1.1
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2
Dimensionality Reduction Methods . . . . . . . . . . . . . . . . . . . . . . 1 1.2.1
Word co-occurrence matrix . . . . . . . . . . . . . . . . . . . . . . 1 1.2.1.1
Principal Component Analysis . . . . . . . . . . . . . . . 2 1.2.1.2
Pointwise Mutual Information Matrix . . . . . . . . . . . 3 1.2.1.3
Skip-Gram with Negative Sampling . . . . . . . . . . . . 3 1.3
Neural Networks Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.3.1
SENNA embeddings . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.3.2
Turian embeddings . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.3.3
HLBL embeddings . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.3.4
Huang's embeddings . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.3.5
Word2vec . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1.3.6
Polyglot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1.4
Cross Lingual Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1.4.1
Klementiev et al. embeddings . . . . . . . . . . . . . . . . . . . . 8 1.4.1.1
Multitask Learning . . . . . . . . . . . . . . . . . . . . . . 9 1.4.1.2
The Neural Network Model . . . . . . . . . . . . . . . . . 9 1.4.2
Karl Moritz Hermann and Phil Blunsom embeddings . . . . . . . . 10 1.5
Problem De nition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 1.5.1
Available methods for tackling the proposed issues . . . . . . . . . 12 1.5.1.1
Using Simple Additive Function . . . . . . . . . . . . . . 13 1.5.1.2
Using Recurrent Neural Network . . . . . . . . . . . . . . 13
2 Proposed Method 15 2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.2 Proposed Framework . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3 Experiments and Results 19 3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3.1.1 Experimental Setting . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3.1.1.1
Choosing the composition function . . . . . . . . . . . . . 19 3.1.1.2
Data preprocessing . . . . . . . . . . . . . . . . . . . . . . 20 3.1.1.3
Training and Parameter Tuning . . . . . . . . . . . . . . 21 3.1.1.4
The Paraphrase Test . . . . . . . . . . . . . . . . . . . . . 22 3.1.1.5
The CLDC Test . . . . . . . . . . . . . . . . . . . . . . . 22 3.1.1.6
Hardware and Software . . . . . . . . . . . . . . . . . . . 23 3.1.2
Experimental Results . . . . . . . . . . . . . . . . . . . . . . . . . 23 3.1.2.1
Extracting the Embeddings . . . . . . . . . . . . . . . . . 24 3.1.2.2
Evaluating the quality of the embeddings . . . . . . . . . 24
4 Conclusion 37 4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
4.2 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Bibliography 4
Fourier transform infrared spectroscopy (FTIR) analysis of silicon carbide nanowires
No full textTezin basılısı, İstanbul Şehir Üniversitesi Kütüphanesi'ndedir.Silicon carbide (SiC) nanowires have attracted particular research enthusiasm for their favorable applications in nanoscale optoelectronics, sensors, high frequency, high temperature, and high-power electronics. A comprehensive Fourier transform infrared spectroscopy (FTIR) analysis of the SiC nanowires has been conducted. FTIR gives very important and practical information about the chemical bond states of materials. FTIR studies showed three strong peaks at the spectrum, which can be assigned to SiC transverse optical (TO) mode, SiC longitudinal optical (LO) mode, and Si-O stretching mode. Further, the differences of phonon states of SiC nanowires compared to the bulk SiC have been discussed. The Si-C TO stretching absorption band ranges from 783 cm−1 to 793 cm−1 withthefullwidthathalfmaximum(FWHM)valuesfrom21cm−1 to36cm−1 with Fe-film catalyst, while the Si-C TO stretching absorption band ranges from 782 cm−1 to 784 cm−1 with the FWHM values from 13 cm−1to 31 cm−1 with Ni-film catalyst. The FWHM values of the TO mode absorption of the SiC nanowires are significantly lower than that of bulk SiC (FWHM 59 cm−1) suggesting higher bond quality and uniformity of the SiC nanowires. Moreover, the SiC TO mode absorption shifted towards the lower wavenumber region compared to the wavenumber of bulk single crystal SiC ( 800 cm−1). These results show that FTIR provides quick and valuable information about the chemical bond states, crystal structure, and crystal quality of the nanostructured materials. Additionally, a practical synthesis method for SiC nanowire fabrication has been discussed; and morphology and crystal structure investigation of the SiC nanowires grown with various catalyst materials has been provided.Declaration of Authorship ii
Abstract iii
Öz iv
Acknowledgments v
List of Figures viii
List of Tables x
Abbreviations xi
1 Introduction 1
1.1 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.3 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2 Properties and Growth of SiC Nanowires 6
2.1 Crystallographic Structures of SiC . . . . . . . . . . . . . . . . . . . . . . 6
2.2 Growth of SiC Nanowires . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.2.1 Chemical Vapor Deposition . . . . . . . . . . . . . . . . . . . . . . 9
2.2.2 Conversion of Carbon Nanotubes (CNTs) and C-Fibers. . . . . . . 11
2.2.3 Arc Discharge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.2.4 Laser Ablation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
2.2.5 High-Frequency Induction Heating . . . . . . . . . . . . . . . . . . 15
2.2.6 SiCNanowiresGrowthMethodBasedonVapor-Liquid-SolidMechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 2.2.7 SiC Nanowires Growth Method Based on Vapor-Solid Mechanism . 16
2.2.8 SiC Nanowires Growth Method Based on Solid-Liquid-Solid Mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 2.3 Properties of SiC Nanowires . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2.3.1 Field Emission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2.3.2 Optical Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2.3.3 Electron Transport Properties . . . . . . . . . . . . . . . . . . . . . 21
2.3.4 Mechanical Properties . . . . . . . . . . . . . . . . . . . . . . . . . 23
2.3.5 Photocatalyst Properties . . . . . . . . . . . . . . . . . . . . . . . . 24
3 Experimental Details 26
3.1 Nanowire Growth Setup and Procedures . . . . . . . . . . . . . . . . . . . 26
3.2 X-ray Diffraction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
3.3 Scanning Electron Microscopy . . . . . . . . . . . . . . . . . . . . . . . . . 29
3.4 Transmission Electron Microscopy . . . . . . . . . . . . . . . . . . . . . . 31
3.5 Fourier Transform Infrared Spectroscopy . . . . . . . . . . . . . . . . . . . 33
4 Structural Characterization of SiC Nanowires 37
4.1 Structural Characterization . . . . . . . . . . . . . . . . . . . . . . . . . . 37
4.2 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
5 Fourier Transform Infrared Spectroscopy Analysis of SiC Nanowires 43
5.1 Fourier Transform Infrared Spectroscopy . . . . . . . . . . . . . . . . . . . 43
5.1.1 Influence of the Substrate Temperature on SiC Nanowire Phonon Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
5.1.2 Phonon Mode Comparison of SiC Nanowires with Different Catalyst Materials at the Same Growth Temperatures . . . . . 47
5.2 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
6 Conclusions and Future Work 56
6.1 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
6.2 Future Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Bibliography 5
