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Multi-Agent Reinforcement Learning for Energy Saving in Multi-Cell Massive Mimo Systems
No full text1st IEEE International Conference on Machine Learning for Communication and Networking, ICMLCN 2024 -- 5 May 2024 through 8 May 2024 -- Stockholm -- 201880We develop a multi-agent reinforcement learning (MARL) algorithm to minimize the total energy consumption of multiple massive MIMO (multiple-input multiple-output) base stations (BSs) in a multi-cell network while preserving the overall quality-of-service (QoS) by making decisions on the multi-level advanced sleep modes (ASMs) and antenna switching of these BSs. The problem is modeled as a decentralized partially observable Markov decision process (DEC-POMDP) to enable collaboration between individual BSs, which is necessary to tackle inter-cell interference. A multi-agent proximal policy optimization (MAPPO) algorithm is designed to learn a collaborative BS control policy. To enhance its scalability, a modified version called MAPPO-neighbor policy is further proposed. Simulation results demonstrate that the trained MAPPO agent achieves better performance compared to baseline policies. Specifically, compared to the auto sleep mode 1 (symbol-level sleeping) algorithm, the MAPPO-neighbor policy reduces power consumption by approximately 8.7% during low-traffic hours and improves energy efficiency by approximately 19% during high-traffic hours, respectively. © 2024 IEEE.VINNOVA; Swedish Innovation Agenc
Highly Stable Tio2/G-c3n4 Composite Electrodes for Quasi-Solid Supercapacitor Applications
No full textTuc Altaf, Cigdem/0000-0001-9036-5836Supercapacitor research focuses on cheap, long-lasting electrode materials. As a semiconductor, titanium dioxide (TiO2) is cheap and chemically stable, making it a promising electrode material for supercapacitors. The goal is to improve carbon-based composites by hybridizing conductive materials. The graphitic carbon nitride (g-C3N4) is a stable and common allotrope of C3N4. Its optical, electrical, and structural properties make it a good hybrid system for supercapacitors. With a simple, affordable, and successful thermal decomposition method, we synthesized a TiO2/g-C3N4 composite material. Supercapacitors have 20.6 F g-1 specific capacitance, 63 Wh kg-1 energy density, and 92 % Coulombic efficiency. The TiO2/g-C3N4 composite showed highly stable electrochemical performance even after 10,000 charge-discharge cycles.The authors would like to thank TUBITAK for their financial support under research grant no 122F390.TUBITAK [122F390
Investigation of voice changes before thyroid surgery with machine learning methods
No full text11. Cerrahi Araştırma KongresiObjective: The study aims to understand the clinical significance of these changes and the potential impact of surgical interventions by examining common vocal changes before thyroid surgery. Material and Methods: The study had a prospective design and data sets were created from the Saarbruecken voice dataset and the “a” and “i” sounds of 126 individuals (34 males, 92 females) in two groups of healthy and thyroid surgery candidates obtained from our clinic, and then processed with signal processing methods and extracted features. These features were used to classify healthy and sick subjects using support vector machines (cubic and quadratic), k-nearest neighbor (k= 5 and k= 7) and ensemble learning (gentleboost and bag) classifiers. After the attributes that were effective in the classification of healthy and patient groups were determined by Shapley value method, Kruskal-Wallis H test with Post Hoc Tamhane’s T2 test, MannWhitney U Test and Spearman correlation test were used to evaluate the changes in attributes. Results: The laryngoscopies of the thyroid surgery candidates included in the study performed in the ENT clinic were normal. All machine learning methods achieved 94.40%-100.00% success in healthy-diseased group discrimination. Shapley analysis identified mid-frequency power, spectral entropy, formant-1 energy and formant-2 energy as effective features for healthy-diseased discrimination; mid-frequency power, formant-2 bandwidth and formant-2 for diseased-healthy “a” sounds discrimination; formant-1, formant-2 bandwidth, formant-2 and mid-frequency power as effective features for “i” sound discrimination in diseased and healthy groups. According to this evaluation, these attributes are effective in the discrimination of healthy-diseased, “a” sounds and “i” sounds. The selection of these attributes is important for improving classification performance and obtaining accurate results. In addition, statistically significant associations (p 0.05) were found between effective attributes and presence of nodules, sex, smoking, and thyroid gland volume. Conclusion: All patients who are candidates for thyroid surgery have a voice disorder, and it is recommended that patients should be evaluated for voice disorder during their previous follow-up and treatment. It is observed that machine learning methods are effective in these evaluations
Introduction to Multiple Antenna Communications and Reconfigurable Surfaces
No full textWireless communication is the backbone of the digitized society, where everything is connected and intelligent. Access points and devices are nowadays equipped with multiple antennas to achieve higher data rates, better reliability, and support more users than in the past. This book gives a gentle introduction to multiple antenna communications with a focus on system modeling, channel capacity theory, algorithms, and practical implications. The basics of wireless localization, radar sensing, and controllable reflection through reconfigurable surfaces are also covered. The goal is to provide the reader with a solid understanding of this transformative technology that changes how wireless networks are designed and operated, today and in the future. The first three chapters cover the fundamentals of wireless channels, and the main benefits of using multiple antennas are identified: beamforming, diversity, and spatial multiplexing. The theory and signal processing algorithms for multiple-input multiple-output (MIMO) communications with antenna arrays at the transmitter and receiver are progressively developed. The next two chapters utilize these results to study point-to-point MIMO channels under line-of-sight (LOS) and non-LOS conditions, covering the shape of signal beams, impact of array geometry, polarization, and ways to achieve reliable communication over fading channels. The book then shifts focus to multi-user MIMO channels, where interference between devices is managed by spatial processing. The next chapter extends the theory to multicarrier channels and explains practical digital, analog, and hybrid hardware implementations. The last two chapters cover the role of multiple antennas in localization and sensing, and how reconfigurable surfaces can improve both communication and sensing systems. The text was developed as the textbook for a university course and builds on the reader's previous knowledge of signals and systems, linear algebra, probability theory, and digital communications. Each chapter contains numerous examples, exercises, and simulation results that can be reproduced using accompanying code
Comparative Overlapping Regionalism: Europe and Asia
No full textBölgeselciliğin yükselişi, daha fazla ülkenin birden fazla bölgesel örgüt ve mekanizmaya katılmasına yol açarak bölgeselciliğin örtüşmesine yol açmıştır. Bu örtüşme olgusu hem bölgesel entegrasyon stratejisi hem de siyasi manevra olarak ikili bir nitelik taşımaktadır. Bu tez, Avrupa ve Asya'daki örtüşen bölgeselciliğin yansımalarını anlamak ve karşılaştırmak için Polanyi'nin çifte hareket kavramından yararlanarak derinlemesine incelemektedir. Bu doğrultuda çalışma, örtüşen bölgeselciliğin esasen bir bölgesel entegrasyon stratejisi olmakla birlikte, devletlerin bölgesel entegrasyon baskıları karşısında ulusal çıkarların korunması için bir dengeleme mekanizması olarak da hizmet ettiğini göstermektedir. Bulgular, örtüşen bölgeselciliğin nedenleri ve etkilerinin bölgeler arasında farklılık gösterdiğini vurgularken, aynı zamanda her iki bölgede de toplumsal ve ulusal çıkarları korumak için karşı hareketlerin oluşmasına ortam hazırladığını göstermektedir.The rise of regionalism has led to more countries joining multiple regional organizations and mechanisms, resulting in overlapping regionalism. This overlapping phenomenon carries a dual nature as both a regional integration strategy and political maneuvering. Thus, this thesis explores the overlaps in regionalism, using Polanyi's double movement concept to understand and compare its appearances in Europe and Asia. Polanyi's perspective provides a holistic understanding of the relationship between regional integration and national interest in overlapping regionalism. In this vein, this study illustrates how overlapping regionalism, while primarily a regional integration strategy, also serves as a mechanism for states to balance regional integration pressures with the preservation of national interests. The findings illustrate that while the motives and effects of overlapping regionalism vary among regions, there are countermovements in both regions to protect societal interests and national autonomy
A Proposal of Child-Friendly Play Space Design Model "skillscape"
No full textÇocuk gelişimi, toplumun geleceğini belirleyen kritik bir unsur olduğundan, çocukların yaşadıkları çevrenin özellikle erken çocukluk döneminde doğru şekillendirilmesi büyük önem taşımaktadır. Çocuklar, mekânda çeşitli deneyimler yaşadıkça mekân bilinci oluşur, algıları uyarılır ve motor gelişimleri desteklenir. Oyun, çocukların fiziksel, zihinsel, duygusal, dilsel ve sosyal gelişimini destekleyen önemli bir öğrenme sürecidir. Bu nedenle, çocuk dostu mekânlar amacına uygun tasarım kriterlerine göre şekillendirilmelidir. Bu çalışmanın amacı, "gelişim dostu" mekân anlayışına yönelik bir model geliştirmektir. Çocuk gelişimini destekleyen mekânsal kriterler belirlenmiş ve örnek bir oyun mekânı önerisi sunulmuştur. Önerilen mekân, erişilebilirlik/ergonomi, güvenlik, estetik, kişisel alan, yaratıcılık, düzen, meydan okuma, hiyerarşi ve özerklik gibi kavramları ele alırken; hayal gücü, merak ve yaratıcılığı destekleyen zengin fiziksel uyaranlara sahip, esnek ve dönüştürülebilir bir tasarıma sahiptir. Tasarım için araştırma yöntemi benimsenmiş, literatür taraması ve anketler ile yarı yapılandırılmış görüşmelerle veriler toplanmıştır. Araştırmada, çocuğun bütünsel gelişimini etkileyen ve katkı sağlayan kriterler belirlenmiş, oyun mekânının nasıl şekillenmesi gerektiği üzerinde durulmuştur. SkillScape oyun alanı modeli, çocuk gelişimini çeşitli açılardan destekleyen bir örnek olarak alana katkı sağlamayı hedeflemektedir.Considering that child development determines the core of a society, addressing every aspect of children's needs should be the primary concern of society. It is crucial for children to live in a supportive environment which significantly influences their education and overall development. For the development of spatial awareness, sensory stimulation, and motor skills, children must have diverse experiences within their environment, primarily acquired through play. Correspondingly, the objective of this study is to develop a model for "child-friendly" play spatial design. After identifying the spatial criteria that support child development, a sample play space is proposed. The proposed space addresses concepts such as; accessibility/ergonomics, safety, aesthetics, personal space, creativity, order, challenge, hierarchy, and autonomy. It is designed as a flexible, transformable environment with rich physical stimuli that foster imagination, curiosity, and creativity. The methodology of this study involves a research-for-design approach. Initially, the educational role of play and play spaces in child development was examined and analyzed through a literature review. Subsequently, the prominent design criteria were evaluated from the perspectives of space designers and child development experts through surveys and semi-structured interviews. The SkillScape play space model aims to contribute to the field as an exemplary space that supports child development from various aspects
Symbolic Self Completion as Mediator Between Nicotine Dependence and Quit Intention: a Nationally Representative Survey
No full textBackgroundThis study aims to investigate the relationship between nicotine dependence and quit intentions, and the degree to which symbolic completion of the self through smoking mediates this relationship. Symbolic self-completion theory assumes that a person seeks to display symbols in relation to how society would respond.MethodsA survey was conducted among a population-based sample of smokers in Turkiye to measure nicotine dependence, intention to quit, and the absence of symbolic self-completion. Mediation analysis was conducted using the Hayes model #4 to investigate the degree to which (symbolic) smoking was linked to dependence and quit intention.ResultsBased on regression analyses, nicotine dependence was found to decrease the intention to quit (coeff = -.039**), while an absence of symbolic self-completion was found to increase quit intention (coeff = .6118**). Symbolic self-completion was found to be a significant (partial) mediator between dependence and quit intentions.LimitationsAlthough the regression approach is utilized in the analysis, this study still relies on cross-sectional data, so further inquiry is needed to establish casual relationships.ConclusionsSmoking is an activity that is publicly noticeable, thereby serving as a symbol of the self within a socio-cultural context. The symbolic power of smoking should be considered along with physical dependence.Global ActionThis study was funded with a grant from Global Action to End Smoking (formerly known as Foundation for Smoke-Free World), an independent, U.S. nonprofit 501(c)(3) grant-making organization, accelerating science- based efforts worldwide to end the smoking epidemic. Global Action played no role in designing, implementing, data analysis, or interpretation of the study results, nor did Global Action edit or approve any presentations or publications from the study. The contents, selection, and presentation of facts, as well as any opinions expressed, are the sole responsibility of the authors and should not be regarded as reflecting the positions of Global Action to End Smoking
Measurement of the H→ Γγ and H→ Zz∗→ 4 ℓ Cross-Sections in Pp Collisions at √s=13.6 Tev With the Atlas Detector
No full textThe inclusive Higgs boson production cross-section is measured in the di-photon and the ZZ∗→ 4 ℓ decay channels using 31.4 and 29.0 fb - 1 of pp collision data respectively, collected with the ATLAS detector at a centre-of-mass energy of s=13.6 TeV . To reduce the model dependence, the measurement in each channel is restricted to a particle-level phase space that closely matches the channel’s detector-level kinematic selection, and it is corrected for detector effects. These measured fiducial cross-sections are σfid,γγ= 76-13+14 fb, and σfid,4ℓ= 2.80±0.74 fb, in agreement with the corresponding Standard Model predictions of 67.6 ± 3.7 fb and 3.67 ± 0.19 fb. Assuming Standard Model acceptances and branching fractions for the two channels, the fiducial measurements are extrapolated to the full phase space yielding total cross-sections of σ(pp→H)=67-11+12 pb and 46 ± 12 pb at 13.6 TeV from the di-photon and ZZ∗→ 4 ℓ measurements respectively. The two measurements are combined into a total cross-section measurement of σ(pp→ H) = 58.2 ± 8.7 pb, to be compared with the Standard Model prediction of σ(pp→ H) SM= 59.9 ± 2.6 pb. © 2024, The Author(s).IN2P3-CNRS; SCI/013; U.S. Department of Energy, USDOE; Alexander von Humboldt-Stiftung, AvH; CRC Health Group, CRC: 21/SCI/017; Canarie; H2020 Marie Skłodowska-Curie Actions, MSCA; Multiple Sclerosis Scientific Research Foundation, MSSRF; CERN; Compute Canada; Göran Gustafssons Stiftelser; Natural Sciences and Engineering Research Council of Canada, NSERC; National Research Council Canada, NRC; Canada Foundation for Innovation, CFI; Science and Technology Facilities Council, STFC; Leverhulme Trust; European Research Council, ERC; European Cooperation in Science and Technology, COST; Australian Research Council, ARC; National Stroke Foundation, NSF; Neurosurgical Research Foundation, NRF; Helmholtz-Gemeinschaft, HGF; Minerva Foundation; Deutsche Forschungsgemeinschaft, DFG; Agence Nationale de la Recherche, ANR; Japan Society for the Promotion of Science, JSPS; Ministry of Education, Culture, Sports, Science and Technology, MEXT; Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, SNF; Danmarks Grundforskningsfond, DNRF; Fundação de Amparo à Pesquisa do Estado de São Paulo, FAPESP; National Natural Science Foundation of China, NSFC; Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT; Fundação para a Ciência e a Tecnologia, FCT; Bundesministerium für Bildung und Forschung, BMBF; Chinese Academy of Sciences, CAS; Austrian Science Fund, FWF; Generalitat de Catalunya; Ministry of Science and Technology of the People's Republic of China, MOST; Agencia Nacional de Promoción Científica y Tecnológica, ANPCyT; Nederlandse Organisatie voor Wetenschappelijk Onderzoek, NWO; Bundesministerium für Wissenschaft, Forschung und Wirtschaft, BMWFW; Conselho Nacional de Desenvolvimento Científico e Tecnológico, CNPq; Nella and Leon Benoziyo Center for Neurological Diseases, Weizmann Institute of Science; Israel Science Foundation, ISF; Instituto Nazionale di Fisica Nucleare, INFN; Narodowe Centrum Nauki, NCN; Javna Agencija za Raziskovalno Dejavnost RS, ARRS; Ministarstvo Prosvete, Nauke i Tehnološkog Razvoja, MPNTR; Ministerio de Ciencia e Innovación, MICINN; Centre National pour la Recherche Scientifique et Technique, CNRST; Staatssekretariat für Bildung, Forschung und Innovation, SBFI; Horizon 2020; British Columbia Knowledge Development Fund, BCKDF; European Regional Development Fund, ERDF; Defence Science Institute, DSI; Narodowa Agencja Wymiany Akademickiej, NAWA; Institutul de Fizică Atomică, IFA; Agencia Nacional de Investigación y Desarrollo, ANID; Royal Society of South Australia, RSSA; Irish Rugby Football Union, IRF
Comparing Some Plant Communities in a Region of Türkiye Via Fuzzy Similarity
No full textIn this study, the results obtained from forest vegetation via the research project on plant sociology which conducted in Black Sea region of Türkiye is evaluated with the help of fuzzy similarity measures approach. Via this project, the plant sociology in an area which has not been studied in Black Sea region of Türkiye is performed to investigate the plant communities and ecological and sociological relationships with each other. The similarity relations among the plant communities and relevés (sampling areas) which they covered are investigated. The issue of fuzzy similarity of sets and elements in sets is studied. According to this point of view, the fuzzy similarity among the plant communities and among the relevés is introduced. This joint study is carried out in a fuzzy environment, considering the classical results found in the project in question to be obtained in more detail for application. It is also understood that such studies can only be the best performed with an interdisciplinary working group