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I Know You Did Not Write That! a Sampling Based Watermarking Method for Identifying Machine Generated Text
No full textPotential harms of Large Language Models such as mass misinformation and plagiarism can be partially mitigated if there exists a reliable way to detect machine generated text. In this paper, we propose a new watermarking method to detect machine-generated texts. Our method embeds a unique pattern within the generated text, ensuring that while the content remains coherent and natural to human readers, it carries distinct markers that can be identified algorithmically. Specifically, we intervene with the token sampling process in a way which enables us to trace back our token choices during the detection phase. We show how watermarking affects textual quality and compare our proposed method with a state-of-the-art watermarking method in terms of robustness and detectability. Through extensive experiments, we demonstrate the effectiveness of our watermarking scheme in distinguishing between watermarked and non-watermarked text, achieving high detection rates while maintaining textual quality. © 2025 International Conference on Computational Linguistics
A Novel Access Point Deployment Framework for mmWave Cell-Free Massive MIMO Networks
No full textMillimeter-wave network deployment is an essential and ongoing problem due to the limited coverage and expensive network infrastructure. In this work, we solve a joint network deployment and resource allocation optimization problem for a mmWave cell-free massive MIMO network considering indoor environments. The objective is to minimize the number of deployed access points (APs) for a given environment, bandwidth, AP cooperation, and precoding scheme while guaranteeing the rate requirements of the user equipments (UEs). Considering coherent joint transmission (C-JT) and non-coherent joint transmission (NC-JT), we solve the problem of AP placement, UE-AP association, and power allocation among the UEs and resource blocks jointly. For numerical analysis, we model a mid-sized airplane cabin in ray-tracing as an exemplary case for IDS. Results demonstrate that a minimum data rate of 1Gbps can be guaranteed with less than 10 APs with C-JT. From a holistic network design perspective, we analyze the trade-off between the required fronthaul capacity and the processing capacity per AP, under different network functional split options. We observe an above 600Gbps fronthaul rate requirement, once all network operations are centralized, which can be reduced to 200Gbps under physical layer functional splits.EU Horizon 2020-Electronics Components and Systems for European Leadership (ECSEL) Joint Undertaking (JU) project Beyond5; EU Horizon 2020 Research and Innovation Programme; Vinnova, Swedish Innovations Agency [876124]; Swedish funding agency VinnovaThis work was supported in part by the EU Horizon 2020-Electronics Components and Systems for European Leadership (ECSEL) Joint Undertaking (JU) project Beyond5 (Building the fully European supplY chain on RFSOI, enabling New RF Domains for Sensing, Communication, 5G and beyond). The Beyond5 project is funded by EU Horizon 2020 Research and Innovation Programme and Vinnova, Swedish Innovations Agency under Grant 876124. This study was conducted partly under Eureka Celtic project RAI-6Green: Robust and AI Native 6G for Green Networks funded by Swedish funding agency Vinnova
Essays on Integrated Macro Policy Frameworks in Small Open Economies
No full textBu tez, finansal kırılganlık, nominal katılıklar ve politika güvenilirliği kısıtları altında küçük açık ekonomilerde bütünleşik makro politika çerçevelerinin tasarımı ve sonuçlarını inceleyen üç makaleden oluşmaktadır. Bu çerçevede, sermaye hareketleri, dışsal şoklar ve politika ödünleşimlerinin makroekonomik istikrar üzerindeki kritik rolünü göz önünde bulunduran ve gelişmekte olan ülke koşullarına özgü dinamik stokastik genel denge modelleri geliştirilmiştir. Teorik modelleme, nicel kalibrasyon ve politika analizi yoluyla, para ve maliye politikaları ile makro ihtiyati ve sermaye akım yönetimi araçlarının bütünleşik bir makro politika çerçevesinde nasıl etkileştiği araştırılmakta ve farklı politika bileşimlerinin makroekonomik istikrara etkileri değerlendirilmektedir. Genel bir girişin yer aldığı I. Bölüm'ün ardından II. Bölüm, para politikası, döviz müdahalesi ve sermaye akımı yönetimi araçlarının birlikte kullanımıyla ilgili politika ödünleşimlerini incelemek üzere bir dinamik stokastik genel denge modeli sunmaktadır. Model, finansal kırılganlıklar, kısıtlı döviz piyasası derinliği ve mali esneklik eksikliği gibi gelişmekte olan ülkeler için ampirik olarak anlamlı bulunan kısıtları içermektedir. Bu bölümün özgün katkısı, mali baskınlığın bütünleşik makro politika çerçevesine dahil edilmesidir. Bu friksiyon, geleneksel para politikasının etkinliğini azaltmakta ve büyüme ile enflasyonda istikrar sağlamak için alternatif araçların kullanımını gerekli kılmaktadır. Simülasyon sonuçları, özellikle mali kısıtların bağlayıcı olduğu durumlarda, döviz müdahaleleri ve sermaye akım yönetimi araçlarının döviz kuru oynaklığını azaltmak ve sermaye akımı şoklarının etkisini hafifletmek suretiyle para politikasının etkinliğini önemli ölçüde artırabileceğini ortaya koymaktadır. III. Bölüm'de, benzer bir dinamik stokastik genekl denge modeli kurulmuş, politika araçlarının etkinliğini şekillendiren politika güvenilirliğinin rolü modellenerek temel çerçeve genişletilmiştir. Bu bölümdeki modelde, iktisadi ajanların politika yapıcının tercihlerini ve kısıtlarını Bayesgil güncelleme ve Kalman filtreleme yoluyla öğrenmesini sağlayan endojen bir politika güvenilirliği mekanizması yer almaktadır. Simülasyon sonuçları, dışsal şokların makroekonomik istikrar üzerindeki etkilerinin, politika güvenilirliğinin sınırlı olduğu durumlarda, daha fazla olduğuna ve para politikasının istikrar sağlayıcı rolünün zayıfladığına işaret etmektedir. Ancak, şeffaf ve kurallara dayalı döviz müdahaleleri gibi güvenilirliği artırıcı mekanizmalar bu olumsuz etkileri dengeleyebilmekte ve politika etkinliğini bir ölçüde sağlayabilmektedir. Bölümde, farklı döviz müdahalesi kurallarının nicel bir karşılaştırması sunularak, müdahale stratejilerinin farklı düzeylerde politika güvenilirliği ile etkileşimleri incelenerek makroekonomik oynaklık üzerindeki etkisilerine vurgu yapılmaktadır. IV. Bölüm, ilk iki bölümü tamamlayarak bütünleşik makro politika çerçevelerine dair kapsamlı teorik ve ampirik bir değerlendirme sunmaktadır. Finansal friksiyonlar altında Mundell-Fleming imkansız üçlemesini yeniden ele almakta ve makroekonomik istikrar açısından bütünleşik politika çerçevesinin önemini vurgulamaktadır. Basu et al. (2020) modeli baz alınarak, farklı bütünleşik makro politika araçlarının alternatif şok senaryoları altındaki performansları özetlenmektedir. Ayrıca, tek bir politika aracı kullanımı ile bütünleşik araç kullanımının etkinliği karşılaştırılmakta; buna yönelik bulguların, özellikle finansal kırılganlığı yüksek olan ekonomilerde, para politikası, makro ihtiyati araçlar ve sermaye akımı politikalarının eşzamanlı kullanılmasının makroekonomik istikrar açısından daha iyi sonuçlar doğurabileceğine işaret ettiği tartışılmaktadır.This thesis comprises three essays exploring the design and implications of integrated macro policy frameworks (IPFs) in small open economies, particularly under financial vulnerability, nominal rigidities, and policy credibility challenges. In these essays, the dissertation develops dynamic stochastic general equilibrium (DSGE) models tailored to emerging market contexts, where capital flows, external shocks, and policy tradeoffs play critical roles in macroeconomic stabilization. Through theoretical modeling, quantitative calibration, and policy analysis, the thesis investigates how monetary, fiscal, macroprudential, and capital flow management tools interact within a unified policy framework and assesses the macroeconomic stabilization outcomes of various policy configurations. Following a general introduction in Chapter I, Chapter II introduces a small open economy DSGE model to quantify the tradeoffs involved in the joint use of monetary policy, foreign exchange intervention (FXI), and capital flow management (CFM) tools. The model incorporates a range of empirically relevant frictions for emerging economies, including financial sector vulnerabilities, limited foreign exchange market depth, and fiscal rigidity. The novel contribution of this chapter lies in integrating fiscal dominance into the IPF framework. This friction alters the effectiveness of conventional monetary policy and necessitates using alternative tools to stabilize output and inflation. Simulation results reveal that FXI and CFM tools can significantly enhance the effectiveness of monetary policy, especially under binding fiscal constraints, by mitigating exchange rate volatility and dampening the transmission of capital flow shocks. Chapter III extends the baseline framework by explicitly modeling the role of policy credibility in shaping the effectiveness of integrated policy tools. It includes an endogenous credibility mechanism, which allows agents to learn about the policymaker's preferences and constraints using Bayesian updating and Kalman filtering. The analysis demonstrates that imperfect credibility amplifies the macroeconomic effects of shocks iv and undermines the stabilizing role of monetary policy. However, credibility-enhancing mechanisms -such as transparent, rule-based FXI policies- can offset these effects and restore policy effectiveness to an extent. The chapter provides a quantitative comparison of different FXI rules, emphasizing how their interactions with different levels of policy credibility influence expectations and macroeconomic volatility. Chapter IV complements the first two chapters by providing a comprehensive theoretical and empirical overview of integrated macro policy frameworks. It revisits the Mundell-Fleming trilemma in the presence of financial frictions and argues for the relevance of policy integration in macroeconomic stabilization. Based on Basu et al. (2020), the chapter summarizes how different combinations of IPF tools perform under alternative shock scenarios. The chapter also presents empirical evidence regarding the effectiveness of standalone versus joint use of IPF instruments. The findings suggest that simultaneous deployment of monetary, macroprudential, and capital flow measures can achieve superior stabilization outcomes, particularly in economies with high financial openness
Elektronik Harp Geniş Bant Almaçlarda Enterferans Etki Analizi
No full textIsik UniversityIn electronic warfare systems, wideband receivers are used to continuously monitor threat signals in the electromagnetic environment. In a modern threat environment, radar signals coexist with various communication signals within the same frequency band. These signals create interference in wideband receivers, hindering the accurate measurement of radar signal parameters. Interfering signals cause varying levels of distortion in digital and analog wideband receivers. In this study, the wideband FFT and instantaneous frequency measurement algorithms are utilized to analyze the impact of parameter estimation under different Signal-to-Interference Ratios (SIR), and their performance is analyzed with different FFT sizes under QPSK modulation. © 2025 Elsevier B.V., All rights reserved
Dynamic Relief Provision Planning for En Route Refugees: Modeling Probabilistic Movements Using Migration Pull Drivers
No full textForced displacement crises have become a pressing humanitarian concern. Refugee movements expose individuals to dire living conditions with severe inaccessibility to essential resources. Humanitarian organizations play a vital role in alleviating these hardships through relief aid interventions. This study aims to optimize the fulfillment of recurring needs for geographically dispersed refugee groups en route to safe destinations. Here, capacitated mobile facilities are tasked with delivering relief aid to refugee groups periodically to ensure equitable service frequency. We formulate the problem as a Markov decision process with multinomial state-transition distributions, shaped by external migration pull factors such as safety conditions, road accessibility, and spatial proximity. The objective is to minimize the relocation and replenishment costs of mobile facilities, along with the deprivation costs faced by underserved refugees. We develop an approximate dynamic programming algorithm featuring a novel policy replication routine. To complement this offline method, we introduce a state-dependent variable threshold policy that enables high-quality, real-time relief provision. Using instances inspired by the Syrian refugee crisis, our results demonstrate the substantial value of stochastic modeling, yielding a 25% reduction in expected total costs compared to deterministic baselines and up to 12% savings through coordinated planning among humanitarian actors. The proposed methods remain effective under dispersed and cohesive refugee group dynamics and multi-destination migration scenarios. Furthermore, we uncover high-frequency traversal and service hotspots along migration paths to provide tactical insights for parameter calibration and resource prepositioning. Collectively, our findings offer practical insights for managing ongoing and future refugee migration crises.Turkiye Bilimsel ve Teknolojik Arascedil;timath;rma Kurumu [119M229]The authors received the following financial support for the research, authorship, and/or publication of this article: This research has been funded by The Scientific and Technological Research Council of Turkiye (TUBTAK) [Grant number 119M229]
NATO’nun Yük Paylaşımında Hegemon Politikaları ve Dış Tehdidin Rolü: Ukrayna Savaşı Örneği
No full textDevletlerin yer aldığı diğer uluslararası kuruluşların birçoğuna benzer biçimde, NATO'ya üye olmanın da bazı faydaları ve maliyetleri bulunmaktadır. Bu üyeliğin sağladığı faydalar genellikle eşit biçimde bölüşülürken maliyetler ise daima aynı oranda üstlenilmemekte ve bu durum yük paylaşımı sorununa yol açmaktadır. Bu tez, söz konusu yük paylaşımını savunma harcamaları üzerinden ele almakta ve bunların farklılaşmasının altında yatan nedenleri araştırmaktadır. Tezde vaka çalışması ve süreç takibi yöntemlerinden faydalanılarak yaklaşık on yıldır devam eden Ukrayna Savaşı sürecine odaklanılmıştır. Hegemonik istikrar ve dış tehdit teorilerine dayanarak saldırgan niyetler (Rusya), hegemonun (ABD) stratejisi ve hegemonun boyutu olmak üzere üç bağımsız değişkenin yük paylaşımına etkisi analiz edilmiştir. Yapılan analiz sonucunda; öncelikle bu iki teorinin birlikte kullanılmasının muhtemel faydaları ortaya konmuştur. Buna ek olarak yük paylaşımında; Obama döneminde hegemon politikaları ve dış tehdidin birbirini dengeleyerek birlikte etkili olduğu, öte yandan Trump döneminde hegemon baskılarının ve Biden döneminde ise artan Rus saldırganlığının temel belirleyici olduğu sonucuna ulaşılmıştır. Dahası, Biden döneminde ABD dışındaki NATO üyelerinin savunma harcamalarında yaşanan artışın diğer dönemlerin ötesine ulaşması, dış tehdidin yük paylaşımında hegemon baskılarından daha etkili olduğunun göstergesi olmuştur.Similar to many other international organizations in which states are a part of, being a member of NATO also has some benefits and costs. While the benefits of this membership are generally shared equally, the costs are not always borne at the same rate, which leads to the problem of burden sharing. This thesis examines this burden sharing through defense expenditures and investigates the underlying reasons for their differences. The thesis focuses on the Ukraine - Russia War process, which has been going on for about ten years, by using case study and process tracing methods. Based on the hegemonic stability and external threat theories, the effects of three independent variables, namely aggressive intentions (Russia), the strategy of the hegemon (USA) and the size of the hegemon, on burden sharing were tested. As a result of the analysis, first of all, the possible benefits of using these two theories together were revealed. In addition, it was concluded that in burden sharing; hegemonic policies and external threats were effective together by balancing each other during the Obama period, while hegemonic pressures during the Trump period and increasing Russian aggression during the Biden period were the main determinants. Moreover, the increase in defense spending of NATO members (excluding the US) during the Biden administiration, which exceeded previous periods, has been an indication that external threats are more effective than hegemonic pressures in burden sharing
Measurement of the Lund Jet Plane in Hadronic Decays of Top Quarks and W Bosons with the ATLAS Detector
No full textThe Lund jet plane (LJP) is measured for the first time in tt¯ events, using 140 fb-1 of s=13 TeV pp collision data collected with the ATLAS detector at the LHC. The LJP is a two-dimensional observable of the sub-structure of hadronic jets that acts as a proxy for the kinematics of parton showers and hadron formation. The observable is constructed from charged particles and is measured for R=1.0 anti-kt jets with transverse momentum above 350 GeV containing the full decay products of either a top quark or a daughter W boson. The other top quark in the event is identified from its decay into a b-quark, an electron or a muon and a neutrino. The measurement is corrected for detector effects and compared with a range of Monte Carlo predictions sensitive to different aspects of the hadronic decays of the heavy particles. In the W-boson-initiated jets, all the predictions are incompatible with the measurement. In the top quark initiated jets, disagreement with all predictions is observed in smaller subregions of the plane, and with a subset of the predictions across the fiducial plane. The measurement could be used to improve the tuning of Monte Carlo generators, for better modelling of hadronic decays of heavy quarks and bosons, or to improve the performance of jet taggers. © 2025 Elsevier B.V., All rights reserved
A Search for Dark Matter Produced in Association with a Dark Higgs Boson Decaying into a Higgs Boson Pair in 3b or 4b Final States Using Pp Collisions at S=13 TeV with the ATLAS Detector
No full textA search is performed for dark matter particles produced in association with a resonant pair of Higgs bosons using 140 fb−1 of proton-proton collisions at a centre-of-mass energy of 13 TeV recorded by the ATLAS detector at the Large Hadron Collider. This signature is expected in some extensions of the Standard Model predicting the production of dark matter particles, and is interpreted in terms of a dark Higgs model containing a Z′ mediator in which the dark Higgs boson s decays into a pair of Higgs bosons. The dark Higgs boson is reconstructed through final states with at least three b-tagged jets, produced by the pair of Higgs boson decays, in events with significant missing transverse momentum consistent with the presence of dark matter. The observed data are found to be in good agreement with Standard Model predictions, constraining scenarios with dark Higgs boson masses within the range of 250 to 400 GeV and Z′ mediators up to 2.3 TeV. © 2025 Elsevier B.V., All rights reserved
Social-Emotional Competence, Executive Functions, and Diet Adherence in Children with Celiac Disease
No full textCeliac disease is a lifelong condition where the immune system reacts to gluten, requiring a strict gluten-free diet that can impact quality of life, especially in children. This study compares the social-emotional and executive function skills of children with and without celiac disease and explores how executive functions influence adherence to the gluten-free diet. Participants consisted of 132 parents with children aged between 5 and 13 (51 with celiac disease, 81 without any illness). Scales were used to measure children's social/behavioral competence, emotion regulation, and executive functions. According to the findings, children with celiac disease had fewer peer problems than those without celiac disease. However, they did not differ in terms of executive functions and emotion regulation skills. Additionally, working memory skills facilitated adherence to the gluten-free diet in children with celiac disease. The implications of the study findings for future research and practical applications are discussed
The Effect of Strut to Face-Sheet Transition Geometry on the Effective Mechanical Properties of Sandwich Panels with Body-Centered Cubic Core Structure
No full textDoğada bulunan bazı cisimler boşluklu yapıya sahiptir ve bu sayede hafif olup yüksek mukavemet elde edebilmektedirler. Bundan ilham alarak havacılık uzay sanayi başta olmak üzere otomotiv, tıp, deniz bilimleri gibi alanlarda giderek daha fazla ilgi gören bu boşluklu yapıdaki malzemeler tasarlanıp üretilmekte ve hücresel malzemeler olarak adlandırılmaktadırlar. Hücresel malzemeler farklı geometrilerde olabilirler, bunlardan birisi de kiriş bazlı hücresel malzemelerdir ve bunlar Kafes Yapılar sınıfında yer alırlar. Geometrik parametrelerinin kolay kontrol edilebilmesi ve üretilebilirlik açısından öne çıkan Hacim Merkezli Kübik Kafes Yapı da en sık kullanılan hücre yapılarından birisidir. Sandviç yapılarda iki yüksek rijitlikte yüzey plakası arasında daha az rijit olan bir çekirdek yapı bulunmakta ve bazı sandviç yapılarda bu çekirdek geometrisi için Hacim Merkezli Kübik Kafes Yapılar kullanılmaktadır. Bu tezde Hacim Merkezli Kübik Kafes Yapı'ya sahip sandviç yapılar modellenip statik yükler ve titreşim altındaki davranışları incelenmiş ve deneyler ile sonlu elemanlar analizi ve homojenizasyon süreci doğrulanmıştır. Deneyler için 3 farklı numune çeşidinden beşer adet olmak üzere toplamda 15 sandviç yapı Toz Yataklı Füzyon teknolojisi ile AlSi10Mg malzemesi ile üretilmiştir. Bunlara mikro yapı taraması, doğal frekans tespiti için titreşim testi ve efektik elastik modül belirlemek için basma testleri yapılmıştır. Bu hücrelerde yüzey plakasına bağlanan kısımlarında bir geçiş yarıçapı oluşturulmuş ve bu geleneksel Hacim Merkezli Kübik yapıya alternatif olarak yeni bir hücre tipi sunulmuştur. Oluşturulan bu yeni hücre ile yeni modeller oluşturulup basma ve eğilme yükleri altında statik analizler ve titreşim analizleri yapılarak Hacim Merkezli Kübik yapı ile karşılaştırılmıştır.Porous structures found in nature offer benefits such as lightweight properties and high strength, driving innovations in industries like aerospace, automotive, medicine, and marine sciences. These increasingly studied porous structures are engineered and manufactured as cellular structures. Among them, strut-based cellular materials, known as Lattice Structures, include the Body-Centered Cubic Lattice Structure, which is notable for its adjustable geometric parameters and ease of fabrication. Sandwich structures consist of a less rigid core layer positioned between two high rigidity surface plates. In some designs, the core incorporates Body-Centered Cubic Lattice Structures. This thesis focuses on modeling sandwich structures with a Body Centered Cubic Lattice core and analyzing their behavior under static loads and vibration. Finite element analysis and the homogenization process were validated through experimental testing. For the experiments, 15 sandwich structures, comprising three different sample types, with five specimens each, were fabricated from AlSi10Mg material using Powder Bed Fusion technology. Microstructural scanning, vibration tests to determine natural frequencies, and compression tests were conducted to assess the effective elastic modulus. A transition radius was introduced in the struts connecting to the surface plate, leading to the development of a novel cell type as an alternative to the conventional Body-Centered Cubic structure. Using this new cell design, additional models were created, and static and vibration analyses were performed under compression and bending loads, comparing their performance with the traditional Body-Centered Cubic structure