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K-Connectivity in Wireless Sensor Networks: Overview and Future Research Directions
No full text-connectivity is a strong notion of robust connectivity. Indeed, in a -connected network, each node has k disjoint paths to all the other nodes in the network. Therefore, even in the case of node/link failure(s), a k-connected wireless sensor network (WSN) remains connected because each node still has, at least, one path to the rest of the surviving nodes. Networks with higher values are, typically, more reliable and fault tolerant than those with lower k values. In this study, we present a systematic and dedicated overview of WSN k-connectivity problem. We, first, outline the k-connectivity detection problem (i.e., determining the k value of a network). Second, we explore the k-connected network deployment problem. Third, we dissect the restoration problem that addresses the rehabilitation of a deteriorated network to restore its original k value. Built upon the provided foundations, we identify and discuss a rich set of important and promising open research problems along with pointers to possible solution approaches. © 1986-2012 IEEE
Investigating Energy Absorption Capability of Additively Manufactured Cuboctahedral Lattice Structures Via Taguchi’s Method: Effects of Process Parameters
No full textThis research aims to investigate the influence of process parameters of fused filament deposition additive manufacturing technique on the energy absorption capacity of cuboctahedral lattice structures using Taguchi’s method. Four process parameters (i.e., print temperature, print speed, layer thickness, and line width) were considered with three levels of parameter values for each, which resulted in nine combinations in Taguchi’s L9 orthogonal array. The lattice structure was fabricated with each of nine combinations of process parameters and tested under a compression load to obtain the energy absorption experimentally. Signal-to-noise ratio analysis was conducted for the results obtained from the experiments of the nine Taguchi sets. Two more lattice specimens were fabricated with the parameter values which resulted in the best and worst energy absorption results and tested. The optimum values of the print temperature, print speed, layer thickness, and line width were determined to be 225 ºC, 30 mm/s, 0.12 mm, and 0.35 mm, respectively. The specific energy absorption (SEA) of the lattice specimen fabricated by using the optimum process parameter values presented 9.4% improvement compared to the highest SEA obtained from the lattices in the Taguchi’s L9 array
Erratum To: Search for Exclusive Higgs and Z Boson Decays To Φγ and Ργ With the Atlas Detector (journal of High Energy Physics, (2018), 2018, 7, (127), 10.1007/Jhep07(2018)127)
No full textOne correction is noted for the paper. The calculation of an angle used to account for meson polarisation in the signal decays was not correct. © The Authors
Tensions in the Enactment of Neoliberal Consumer Responsibilization for Waste
No full textResearch has explored consumer responsibilization processes, yet there is a lack of understanding about the tensions that consumers might experience when enacting their responsibility. Using a large data set collected in France around waste responsibilization, we demonstrate how waste pathways can generate spatiotemporal, guidance, and destructiveness tensions in households. Consumers respond to such tensions by keeping waste at home, which allows them to suspend, clarify, or reappropriate their waste responsibility. In delineating the waste responsibility tensions, our study reveals the boundaries of neoliberal governance's success in mobilizing entrepreneurial consumers' actions, namely, community structure/shared vision, emotions, and market demand. These boundaries illustrate the challenges for neoliberal governance in providing and maintaining for consumers an illusion of control through the crafting of heightened uncertainty, abstraction, and risk-benefit categorizations. This study has implications for waste management actors, as well as consumer researchers interested in neoliberal governance, consumer responsibilization, consumer activism, sustainability, and waste disposal
Low-Bit Quantization for Deep Graph Neural Networks With Smoothness-Aware Message Propagation
No full text32nd ACM International Conference on Information and Knowledge Management, CIKM 2023 -- 21 October 2023 through 25 October 2023 -- 193792ACM SIGIR;ACM SIGWEBGraph Neural Network (GNN) training and inference involve significant challenges of scalability with respect to both model sizes and number of layers, resulting in degradation of efficiency and accuracy for large and deep GNNs. We present an end-to-end solution that aims to address these challenges for efficient GNNs in resource constrained environments while avoiding the oversmoothing problem in deep GNNs. We introduce a quantization based approach for all stages of GNNs, from message passing in training to node classification, compressing the model and enabling efficient processing. The proposed GNN quantizer learns quantization ranges and reduces the model size with comparable accuracy even under low-bit quantization. To scale with the number of layers, we devise a message propagation mechanism in training that controls layer-wise changes of similarities between neighboring nodes. This objective is incorporated into a Lagrangian function with constraints and a differential multiplier method is utilized to iteratively find optimal embeddings. This mitigates oversmoothing and suppresses the quantization error to a bound. Significant improvements are demonstrated over state-of-the-art quantization methods and deep GNN approaches in both full-precision and quantized models. The proposed quantizer demonstrates superior performance in INT2 configurations across all stages of GNN, achieving a notable level of accuracy. In contrast, existing quantization approaches fail to generate satisfactory accuracy levels. Finally, the inference with INT2 and INT4 representations exhibits a speedup of 5.11 × and 4.70 × compared to full precision counterparts, respectively. © 2023 Copyright held by the owner/author(s). Publication rights licensed to ACM.Engineering and Physical Sciences Research Council, EPSRC: EP/T51794X/
Differentiation of Benign and Malignant Thyroid Nodules With Anfis by Using Genetic Algorithm and Proposing a Novel Cad-Based Risk Stratification System of Thyroid Nodules
No full textThe thyroid nodule risk stratification guidelines used in the literature are based on certain well-known sonographic features of nodules and are still subjective since the application of these characteristics strictly depends on the reading physician. These guidelines classify nodules according to the sub-features of limited sonographic signs. This study aims to overcome these limitations by examining the relationships of a wide range of ultrasound (US) signs in the differential diagnosis of nodules by using artificial intelligence methods. An innovative method based on training Adaptive-Network Based Fuzzy Inference Systems (ANFIS) by using Genetic Algorithm (GA) is used to differentiate malignant from benign thyroid nodules. The comparison of the results from the proposed method to the results from the commonly used derivative-based algorithms and Deep Neural Network (DNN) methods yielded that the proposed method is more successful in differentiating malignant from benign thyroid nodules. Furthermore, a novel computer aided diagnosis (CAD) based risk stratification system for the thyroid nodule's US classification that is not present in the literature is proposed
Outbreaks Due To Parasites: Examples From the World and T?rkiye
No full textOutbreaks due to parasites can occur in various parts of the world and in different periods. These outbreaks can be caused by water and food, as well as by human-to-human or vector-borne transmission. Cryptosporidium spp. and Giardia intestinalis were among the pathogens that affected most people in water-borne outbreaks occurred in the world between 2010-2014. The chlorine resistance of both Cryptosporidium spp. and Giardia spp. leads to the widespread detection of these parasites in waterborne outbreaks. These two protozoans cause self-limiting watery diarrhea in immunocompetent individuals, but they can also cause chronic disease in certain situations. Apart from this, parasites such as Cyclospora spp., Cryptosporidium spp., Giardia intestinalis, Trichinella spp. and Toxoplasma gondii can also cause food -borne outbreaks. In Tarkiye, outbreaks related to these parasites have emerged with the neglect of the notification. Some parasites transmitted from person to person can also pose a threat to public health in certain periods. Head lice, the most common examples of such parasites, can cause outbreaks in certain periods. Another example for human-induced parasitic outbreaks is scabies. There has been an increase in scabies rates in the world and in Tarkiye, especially due to the Coronavirus disease-2019 (COVID-19) pandemic. In the first period of the pandemic, it was thought that due to the curfew restrictions, family members spending time at home might have led to an increase in the rate of scabies. On the other hand, as a result of the disruption of services due to COVID-19, the cases of malaria, a vector-borne disease, and the resulting deaths increased in 2020 compared to 2019 in the world. Although only imported malaria cases are detected in Tarkiye today, there is a potential for an outbreak to occur at any time due to the presence of malaria vectors. An outbreak of imported malaria occurred in Mardin in 2012 due to a lorry driver entering the country from an endemic region. Immigrants that reside in Tarkiye pose a risk for some infectious diseases due to the circumstances during migration or the conditions in their living areas. Leishmaniasis, which maintains its importance in the Mediterranean region, is another vector-borne disease and can be detected in Tarkiye, especially in regions where immigrants reside. Bed bug infestations, which have increased recently, also closely affect the provision of health services. It is important to implement regular inspections in regions with outbreak potential, and to ensure the continuity of hygiene conditions and health services to prevent a possible outbreak. In case of an outbreak, different centers should cooperate, health authorities and academics should act together, patients and their contacts should be identified quickly and necessary precautions should be taken, the society should be informed and the outbreak should be taken under control in a short time. In this review article, outbreaks caused by parasites were examined under four headings as water, food, human and vector/arthropod-borne and examples from the world and Tarkiye were given for these outbreaks
Investigation of Upper Bound for the Ruin Probability by Approximate Methods in a Nonlinear Risk Model With Gamma Claims
No full text5th International Conference on Problems of Cybernetics and Informatics, PCI 2023 -- 28 August 2023 through 30 August 2023 -- 195003This study considers a non-linear Cramér-Lundberg model of the risk theory and investigates the adjustment coefficient when the claims have gamma distribution. The ruin probability of this non-linear risk model is considered when the premium function is square root of time. Thus, in this study, the adjustment coefficient is explored by numerical methods and proposed an approximate formula for practical calculation of adjustment coefficient. Moreover, an implementation of the obtained approximate formula, which investigates ruin probability, is included as an example at the end of the paper. © 2023 IEEE
Abd Kongresinde Türkiye Tartışmalarının Savunma Sanayi Transferine Etkisi: 2001-2022
No full textThe defense industry plays a crucial role in maintaining state sovereignty and national security, making it a vital component of a country's defense strategy and foreign policy. Within the United States' political system, the Congress is authorized to enact authorization and appropriation laws, holding significant influence over defense policies and industry management. This thesis focuses on examining the defense industry supply issues between Turkey and its main supplier, the US. Specifically, this thesis aims to analyze the impact of Congress discussions about Turkey on defense industry transfers. A comprehensive data set was created by analyzing congressional discourse and legislative proposals related to Turkey from 2001 to 2022 to ascertain the content, variety, and quantity of issues against Turkey. Thus, it has been revealed that as the variety and quantity of anti-Turkey issues increased in the U.S. legislative body, negative decisions regarding defense industry transfers to Turkey were made irrespective of the views of the U.S. President and the executive branch. Based on the findings, it has been determined that the year 2019, marked by various events and crises, marked the zenith of anti-Turkey sentiments, and during this period, it was observed that decisions against defense industry transfers to Turkey were relatively easier to make.Savunma sanayi, devletlerin egemenliğini sürdürmesi ve milli güvenliğin sağlanmasında askeri gücün tamamlayıcısıdır. Bu durum savunma sanayi yönetimini devletlerin savunma stratejisinin ve dış politikasının önemli bir unsuru haline getirmektedir. ABD politik sisteminde yetkilendirme ve bütçe yasalarını oluşturmada yetkili Kongre, savunma politikaları ve savunma sanayi yönetimi kararlarının belirlenmesinde öncelikli etkiye sahiptir. Türkiye'nin ana tedarikçisi ABD ile yaşadığı savunma sanayi tedariki problemlerinin saptanması bu tez çalışmasının başlangıç noktasını oluşturmaktadır. 2001-2022 dönemi ABD Kongresinde Türkiye aleyhine konuların içeriği, çeşitliliği ve miktarının tespit edilmesini sağlamak için Kongredeki Türkiye aleyhine söylem ve yasa önerilerinin taranması ile bir veri seti oluşturulmuştur. Böylece ABD yasama organında Türkiye aleyhine konuların çeşitliliği ve miktarı arttıkça, ABD Başkanı ve yürütme organının görüşü fark etmeksizin, Türkiye'ye savunma sanayi transferine ilişkin konularda olumsuz karar verildiği ortaya konmuştur. Elde edilen bulgular neticesinde gerçekleşen çeşitli olaylar ve krizler nedeni ile Türkiye karşıtlığının en çok olduğu 2019 yılının bir yığılma dönemi niteliği gösterdiği tespit edilmiş, bu dönemde Türkiye'ye savunma sanayi transferinde aleyhte kararlar alınmasının görece kolaylaştığı gözlemlenmiştir
