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Practical cryptanalysis of full sprout with TMD tradeoff attacks
No full textThe internal state size of a stream cipher is supposed to be at least twice the key length to provide resistance against the conventional Time-Memory-Data (TMD) tradeoff attacks. This well adopted security criterion seems to be one of the main obstacles in designing, particularly, ultra lightweight stream ciphers. At FSE 2015, Armknecht and Mikhalev proposed an elegant design philosophy for stream ciphers as fixing the key and dividing the internal states into equivalence classes where any two different keys always produce non-equivalent internal states. The main concern in the design philosophy is to decrease the internal state size without compromising the security against TMD tradeoff attacks. If the number of equivalence classes is more than the cardinality of the key space, then the cipher is expected to be resistant against TMD tradeoff attacks even though the internal state (except the fixed key) is of fairly small length. Moreover, Armknecht and Mikhalev presented a new design, which they call Sprout, to embody their philosophy. In this work, ironically, we mount a TMD tradeoff attack on Sprout within practical limits using 2d output bits in 271−d encryptions of Sprout along with 2d table lookups. The memory complexity is 286−d where d ≤ 40. In one instance, it is possible to recover the key in 231 encryptions and 240 table lookups if we have 240 bits of keystream output by using tables of 770 Terabytes in total. The offline phase of preparing the tables consists of solving roughly 241.3 systems of linear equations with 20 unknowns and an effort of about 235 encryptions. Furthermore, we mount a guess-and-determine attack having a complexity about 268 encryptions with negligible data and memory. We have verified our attacks by conducting several experiments. Our results show that Sprout can be practically broken. © Springer International Publishing Switzerland 2016
Development and quality of life in Turkey:how globalization, religion, and economic growth influence individual well-being
No full textRecently, scholars have been calling attention to the macro-social and institutional structures shaping development and welfare. In this study we offer a socio-temporally situated understanding of quality of life (QOL) in a developing country setting and investigate the effects of macro structures on consumer well-being. Specifically, we focus on neoliberal development (led by the business sector, rather than led or directed by the government) and examine how a neoliberal transformation of the marketplace affects consumers’ QOL perceptions. The context of our research is Turkey, a developing country that has been an avid follower of neoliberal policies since the 1990s. We focus on three key macro-social developments that have been shaping Turkish society in the past decades – globalization, religion, and economic growth – and seek to understand how these forces influence consumers’ satisfaction with life. Our study contributes to the literature on development and QOL by first, showing the moderating effect of income, and second, introducing faith and global brands as important variables in conceptualizing QOL
Multilane traffic density estimation with KDE and nonlinear LS and tracking with Scalar Kalman filtering
No full textTezin basılısı, İstanbul Şehir Üniversitesi Kütüphanesi'ndedir.With increasing population, the determination of traffic density becomes very critical in managing the urban city roads for safer driving and low carbon emission. In this study, Kernel Density Estimation is utilized in order to estimate the traffic density more accurately when the speeds of the vehicles are available for a given region. For the proposed approach, as a first step, the probability density function of the speed data is modeled by Kernel Density Estimation. Then, the speed centers from the density function are modeled as clusters. The cumulative distribution function of the speed data is then determined by Kolmogorov-Smirnov Test, whose complexity is less when compared to the other techniques and whose robustness is high when outliers exist. Then, the mean values of clusters are estimated from the smoothed density function of the distribution function, followed by a peak detection algorithm. The estimation of variance values and kernel weights, on the other hand, are found by a nonlinear Least Square approach. As the estimation problem has linear and non-linear components, the nonlinear Least Square with separation of parameters approach is adopted, instead of dealing with a high complexity nonlinear equation. Finally, the tracking of former and latter estimations of a road is calculated by using Scalar Kalman Filtering with scalar state - scalar observation generality level. Simulations are carried out in order to assess theperformanceoftheproposedapproach. Forallexampledatasets, theminimummean square error of kernel weights is found to be less than 0.002 while error of mean values is found to be less than 0.261. The proposed approach was also applied to real data from sample road traffic, and the speed center and the variance was accurately estimated. By using the proposed approach, accurate traffic density estimation is realized, providing extra information to the municipalities for better planning of their cities.Declaration of Authorship ii
Abstract iii
Öz iv
Acknowledgments vi
List of Figures ix
List of Tables x
Abbreviations xi
1 Introduction 1
1.1 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Methods to Find Probability Density Function and Cumulative Distribution Function . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
1.3 Traffic Density Estimation with Kernel Density Estimation . . . . . . . . 4
1.4 The Approaches for Determination of Key Parameters of Traffic Density Estimation . . . . . . . . . . . . . . . . . . . . . . . . . . .5
1.5 Tracking between Estimated Data and New Data . . . . . . . . . . . . . . 6
1.6 Thesis Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2 Literature Review 7
2.1 Methodologies Used for Estimation of Traffic Density . . . . . . . . . . . . 7
2.2 An Example Study of Traffic Density Estimation with KDE and CvM . . 9
2.3 Three Complementary Studies for Traffic Density Estimation and Tracking 9
2.4 Comparison of Three Different Nonlinear Estimation Techniques on the Same Problem . . . . . . . . . . . . . . . . . . . . . . . . .10
2.4.1 A Maximum Likelihood Approach for Estimating DS-CDMA Multipath Fading Channels . . . . . . . . . . . . . . . . . . . . . . . . 12 2.4.2 Channel Estimation for the Uplink of a DS-CDMA System . . . . 12
2.4.3 A Robust Method for Estimating Multipath Channel Parameters in the Uplink of a DS-CDMA System. . . . . . . . . . . . . . .13
3 The Model 16
3.1 Finding Density Distribution with KDE . . . . . . . . . . . . . . . . . . . 16
3.2 Finding Empirical CDF with KS Test . . . . . . . . . . . . . . . . . . . . 18
3.3 Determination of Speed Centers via PDA . . . . . . . . . . . . . . . . . . 20
3.4 Estimation of Variance and Kernel Weights with Nonlinear LS Method . . 21
3.5 Tracking of Traffic Density Estimation with Scalar Kalman Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
4 Numerical Calculations for Traffic Density Estimation 26
4.1 An Example Traffic Scenario with Five Speed Centers . . . . . . . . . . . 26
4.2 The Estimation of A Real Time Data . . . . . . . . . . . . . . . . . . . . . 29
4.3 Traffic Density Estimation with Different Kernel Numbers . . . . . . . . . 29
5 Examples to Test Tracking Part of the Model 31
5.1 Tracking with the Change only in Mean Values . . . . . . . . . . . . . . . 32
5.2 Tracking with the Change only in Kernel Weights . . . . . . . . . . . . . . 35
5.3 Tracking with the Change in All Three Parameters . . . . . . . . . . . . . 36
6 Assesment 38
7 Conclusion 41
A Derivation of Newton-Raphson Method for the Estimation of Variance Values and Kernel Weights 43
Bibliography 4
Uncertainty-embedded dynamic life cycle sustainability assessment framework:an ex-ante perspective on the impacts of alternative vehicle options
No full textAlternative vehicle technologies have a great potential to minimize the transportation-related environmental impacts, reduce the reliance of the U.S. on imported petroleum, and increase energy security. However, they introduce new uncertainties related to their environmental, economic, and social impacts and certain challenges for widespread adoption. In this study, a novel method, uncertainty-embedded dynamic life cycle sustainability assessment framework, is developed to address both methodological challenges and uncertainties in transportation sustainability research. The proposed approach provides a more comprehensive, system-based sustainability assessment framework by capturing the dynamic relations among the parameters within the U.S. transportation system as a whole with respect to its environmental, social, and economic impacts. Using multivariate uncertainty analysis, likelihood of the impact reduction potentials of different vehicle types, as well as the behavioral limits of the sustainability potentials of each vehicle type are analyzed. Seven sustainability impact categories are dynamically quantified for four different vehicle types (internal combustion, hybrid, plug-in hybrid, and battery electric vehicles) from 2015 to 2050. Although impacts of electric vehicles have the largest uncertainty, they are expected (90% confidence) to be the best alternative in long-term for reducing human health impacts and air pollution from transportation. While results based on deterministic (average) values indicate that electric vehicles have greater potential of reducing greenhouse gas emissions, plug-in hybrid vehicles have the largest potential according to the results with 90% confidence interval
Improvisation with the lexical approach
No full textIn this research, our main purpose is to attempt to promote the speaking strategies of prep students focusing basically on lexical chunks, personalizing communicative competence and amusing feature motivation by ⿿improvisation⿿. Teaching vocabulary within a contextualized situation is highly influential compared to current approaches, and integrating post-speaking activities with an acting is opted for more frequently, as learners are required to use implicitly acquired structures in another productive skill, with the philosophy ⿿language as a means⿿. This study was conducted to look into the effects of improvisation on the speaking strategies and lexical competence of preparatory students in School of foreign languages at Istanbul ſehir University. It was designed as a both qualitative and quantitative method. The data was collected through the content analysis by means of rubrics. With the help of those instruments, the effectiveness of improvisation so as to promote speaking strategies and lexical competence of students in pre-intermediate level was tested. The other aim of the study is to find out if students⿿ vocabulary knowledge could be improved through improvisation and the last aim is to find out students⿿ attitudes towards improvisation in terms of lexical items. In the light of the data analysis, the result and the analysis of the vocabulary and speaking rubrics revealed that participants succeeded in promoting their speaking strategies and lexical competence. Study result has revealed that students had positive impact toward vocabulary learning in the speaking process. Data results have also shown that, learners were actively participants
Algorithms for wireless communication systems using SDR platform
No full textTezin basılısı İstanbul Şehir Üniversitesi Kütüphanesi'ndedir.This thesis presents a detailed study on software based channel emulators and a set of algorithms pertaining to the soft emulator. With the fact that several wireless communications technologies were released in the last decades, there are a lot of challenging issues emerging due to the need for faster and more reliable technologies. From these challenging issues, we have chosen to focus our research on two outstanding challenges: real-time software channel emulator and automatic modulation classification.
Recently, there has been an increase in the demand for a reliable and low-cost channel emulator to study the effects of real wireless channels. Hence, in the first part of the thesis, wediscussanimplementationofareal-timesoftwarechannelemulator. Thereal-time fading channel emulator was implemented by using a software defined radio platform. In order to verify the model, the frequency spectrum specifications of the channel generated was checked with a double tone transmitter. Then as a second step of verification, bit error rate (BER) of a real-time Orthogonal Frequency Division Multiplexing system using the Universal Software Radio Peripheral (USRP) and LABVIEW software was compared with the BER floor calculated from the theoretical equations. It has been shown that the developed channel emulator can indeed emulate a fading wireless channel.
In the second part of the thesis we focused on covering an issue related to blind estimation or classification of a parameter in wireless communications at the receiver. This problem appears in cognitive radios and some defense applications where the receivers needs to know the type of the modulation of an incoming signal. The efficient automatic modulation classification scheme proposed in this study can be utilized for a group of digitally modulated signals such as QPSK, 16-PSK, 64-PSK, 4-QAM, 16-QAM, and 64QAM. 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 and analyzing the probability density distribution for the real and imaginary parts of the modulated signals. Simulations were carried out to evaluate the performance of the proposed scheme for flat channels.
Thus, in this thesis first of all we were able to develop a software based channel emulator. The developed channel emulator can be a very useful tool for other researchers in testing their real-time systems on a verified Doppler channel. Moreover, the emulator can find other applications from education to wireless device developments due to its flexibility. On the other hand, with the automatic modulation classification, the unknown modulation of an incoming signal can be determined. Hence, the two issues can be combined to find applications in cognitive radio developments.Abstract iii
Öz v
Acknowledgments viii
List of Figures xi Abbreviations xiii
1 Introduction and Literature Review 1
1.1 Channel Emulators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Automatic Modulation Classification . . . . . . . . . . . . . . . . . . . . . 4
1.3 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2 Real Time Fading Channel Emulator using SDR 8
2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.2 Implementation of fading channels . . . . . . . . . . . . . . . . . . . . . . 10
2.2.1 Implementation of Multipath Doppler Channel . . . . . . . . . . . 13
2.2.2 Specifications of the OFDM system used in verification . . . . . . 14
2.3 Theoretical BER curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2.4 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.4.1 First verification phase . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.4.2 Second verification phase . . . . . . . . . . . . . . . . . . . . . . . 19
2.4.3 Multipath channel simulation results . . . . . . . . . . . . . . . . . 21
2.4.4 Sources of error and mismatch . . . . . . . . . . . . . . . . . . . . 22
2.5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
3 Automatic Modulation Classification based on Kernel Density Estimation 25
3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
3.2 System model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
3.2.1 System model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
3.2.2 Signal model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
3.2.3 KDE for the Modulation estimation . . . . . . . . . . . . . . . . . 28
3.2.4 Filtering to improve modulation estimation . . . . . . . . . . . . . 29
3.2.5 AMC proposed flow diagram . . . . . . . . . . . . . . . . . . . . . 31
3.3 Simulation results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
3.3.1 Choosing parameters . . . . . . . . . . . . . . . . . . . . . . . . . . 32
3.3.2 Simulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
3.3.3 Complexity Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . 37
3.4 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
4 Conclusion and Future Work 40
4.1 Channel emulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
4.2 Automatic Modulation Classification . . . . . . . . . . . . . . . . . . . . . 41
4.3 Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
A Proof for equation 2.4 used to calculate the BER for a given fading channel with certain fD 43
B LABVIEW diagram used to generate the curves in Figure 2.14 46
Bibliography 4
Ottoman Istanbul in flames : city conflagrations governance and society in the early modern period
No full textThis Master’s thesis is an inquiry into the Ottomans’ perception of fires and urban regulations. Analyzing official sources, such as court records and archival sources, this thesis aims to understand the Ottomans’ role and mindset toward the city reconstruction after fires. Also, by cross-checking official with non-official sources, i.e. traveler accounts, the reports of diplomats (official, non-Ottoman records), drawings and secondary sources, this thesis provides a broader picture on the manner in which the Ottomans dealt with the outcome of fires in the capital.
Fires are significant to study due to the immense change they brought to urban life which make it possible to trace the policies, approaches, and regulations of the city rulers. When it comes to fires in the 18th century Istanbul, the Ottoman Empire’s responsibility to return the city to pre-fire conditions, and bring normalcy to city life played a crucial role. However, the role of the society, reconstruction of the physical environment, rehabilitation of the social life, and affecting political regulations of the state was of great importance as well.
Looking at the socioeconomic effects of fires, and the way in which official politics dealt with the problem, the thesis aspires to answer the questions: how responsive were the Ottomans in dealing with the fires, and what was prioritized in the reconstruction of the city. Researching further into the social aspect of fires, and the social consciousness about the problem of fire, we attempt to understand the participation of society in the effectuating and establishing relevant regulations. The processes that took place in the aftermath of fires in different parts of the world was taken into consideration for the sake of approaching fires from a comparative angle. The thesis contributes to the history of fires of the Ottoman Empire by focusing on the capital city, Istanbul (walled city) in the pre-modern period.ABSTRACT ................................................................................................................ iv
ÖZ ............................................................................................................................... vi ACKNOWLEDGMENTS .......................................................................................... ix
TABLE OF CONTENTS ........................................................................................... xii
LIST OF TABLES .................................................................................................... xiv
LIST OF FIGURES ................................................................................................... xv
CHAPTERS 1. INTRODUCTION ................................................................................................... 1
1.1. Sources ............................................................................................................. 3
1.2. Literature Review ............................................................................................. 5
1.3. Outline .............................................................................................................. 8
2. USING GIS AND MAPPING FIRES: LISTING AND VISUALIZATION OF ISTANBUL FIRES .................................................................................................... 10
2.1. GIS and Sources for Data ............................................................................... 13
2.2. Fire Rating and Maps ..................................................................................... 21
3. ISTANBUL FIRES: REASONS, PERCEPTIONS AND PRECAUTIONS ......... 28
3.1. Effects of Nature on Fire Behavior ................................................................ 32
3.2. Gunpowder and Fires ..................................................................................... 37
3.3. Smoking and Fires .......................................................................................... 37
3.4. Firefighters and Fire-starters in the Capital: Reasons, Motivations, and Punishments ........................................................................................................... 38
3.5. Fires By Months: Did Fires Occur Mostly In Summers? ............................... 47
3.6. Perceptions and Precautions ........................................................................... 48
4. DEALING WITH FIRES: FIREFIGHTING AND RECOVERY IN TULUMBA AGE ........................................................................................................................... 56
4.1. 18th Century Hocapaşa and Cibali Fires ......................................................... 57
4.2. Firefighting: Corps and Techniques, Towers and Rewards ........................... 62
4.3. Alternative Approach to the City Fires: Diverse Aspects of Regulations after Fires ....................................................................................................................... 73
4.3.1. Tax Reductions until Completion of Reconstruction ............................. 79
4.3.2. Regulations on Sheltering ....................................................................... 82
4.3.3. Building Codes ....................................................................................... 83
5. CONCLUSION ...................................................................................................... 89
BIBLIOGRAPHY ...................................................................................................... 95
APPENDICES ......................................................................................................... 106
A. Refik Efendi’s poet expressing how a burned house could be a misery for officers....................... 106
B. The case of Waqf of Emine Hatun...................................... 107
C. The number of firefighters and tulumbas in Istanbul belonging to different corps, namely, the Janissaries, Cebeci, Topçu, Arabacı Topçu, Tersane-i Âmire, and Bostancı ........................ 10
Power-aware delay test quality optimization for multiple frequency domains.
No full textAs the number of frequency domains aggressively grows in today’s systems-on-chip (SoCs), the delivery of highdelay test quality across numerous frequency domains while meeting test budgets assumes crucial importance. This paper proposes a method to explore the delay test quality tradeoffs across these domains, determining an optimal distribution of the test time budget across all domains while minimizing the overall SoC delay defect escape level. Satisfaction of this goal necessitates not only consideration of fault coverage but also of the distinct characteristics of each domain, such as frequency, path length distribution, scan length, and shift speed as well as full utilization of concurrent test support while remaining within the constraints of power thresholds to provide a reliable test environment. An optimization formulation as well as efficient test time allocation methods based on convexity and fast concurrent test planning algorithms are provided
Cyber warfare:terms, issues, laws and controversies
No full textRecent years have shown us the importance of cybersecurity. Especially, when the matter is national security, it is even more essential and crucial. Increasing cyber attacks, especially between countries in governmental level, created a new term cyber warfare. Creating some rules and regulations for this kind of war is necessary therefore international justice systems are working on it continuously. In this paper, we mentioned fundamental terms of cybersecurity, cyber capabilities of some countries, some important cyber attacks in near past, and finally, globally applied cyber warfare law for this attacks
Fourier transform infrared spectroscopy of silicon carbide nanowires
No full textSilicon carbide (SiC) nanowires have been grown on by hexamethyldisilane (HMDS) using iron and nickel catalysts at temperatures between 900 and 1100°C under H2. The morphologies and bonding states were investigated by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The results show that the assynthesized nanowires are high-quality crystals with high aspect ratios. Moreover, high density of SiC nanowires have been successfully grown even at a low temperature of 900°C. Additionally, it has been observed that the phonon states of SiC nanowires are different from the bulk SiC. The SiC TO mode shifted to lower wavenumber compared to bulk SiC. Furthermore, the FWHM value of the TO mode absorption of the SiC nanowires is only 13cm-1, which is lower than that of bulk SiC (59cm-1). The sharp and consistent TO modes indicate very good bonding uniformity of the SiC nanowires