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Artykuły w czasopismach na temat "CH NODE"
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Rehman, Eid, Muhammad Sher, Syed Hussnain Abbas Naqvi, Khan Badar Khan i Kamran Ullah. "Energy Efficient Secure Trust Based Clustering Algorithm for Mobile Wireless Sensor Network". Journal of Computer Networks and Communications 2017 (2017): 1–8. http://dx.doi.org/10.1155/2017/1630673.
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The main benefit of selecting a suitable node as cluster head (CH) in clustering for wireless mobile sensor networks (MWSNs) is to prolong the network lifetime. But the safe selection of CH is a challenging task by taking security into account. Mostly CH selection algorithms in MWSN do not consider security when selecting CH. We have proposed secure CH selection algorithm by calculating weight of each node to deal with secure selection using minimum energy consumption. The weight of node is a combination of different metrics including trust metric (behaviors of sensor node) which promotes a secure decision of a CH selection; in terms of this, the node will never be a malicious one. The trust metric is definitive and permits the proposed clustering algorithm to keep away from any malignant node in the area to select a CH, even if the rest of the parameters are in its favor. Other metrics of node include waiting time, connectivity degree, and distance among nodes. The selection of CHs is completed utilizing weights of member nodes. The preparatory outcomes acquired through simulation exhibit the adequacy of our proposed scheme as far as average rate of avoiding malicious node as a CH, energy efficiency, and some other performance parameters are concerned.
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Fallo, Kristoforus, Waskitho Wibisono i Kun Nursyaful Priyo Pamungkas. "Pengembangan mekanisme grid based clustering untuk peningkatan kinerja LEACH pada lingkungan Wireless Sensor Network". Register: Jurnal Ilmiah Teknologi Sistem Informasi 5, nr 2 (1.07.2019): 164. http://dx.doi.org/10.26594/register.v5i2.1708.
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Development of a grid-based clustering mechanism to improve LEACH performance in the Wireless Sensor Network environmentLow Energy Adaptive Clustering Hierarchy (LEACH) merupakan algoritma routing pada Wireless Sensor Network (WSN) berbasis cluster. LEACH memilih sebuah node sebagai cluster head (CH) yang tugasnya untuk melakukan komunikasi dengan sink maupun guna mengumpulkan data dari member node. Persebaran CH pada LEACH yang dikatakan acak, kadang mengalami masalah mengingat rumus probabilitas pada tiap round. Hal ini akan menyebabkan CH yang terpilih bisa berada di tepi area, juga terjadinya pemborosan energi karena jalur yang terbentuk akan menjadi panjang. Oleh karena itu, kami ingin mengembangkan routing protocol G-LEACH menggunakan teknik merge CH dalam suatu area (grid) disertai beberapa parameter yang relevan, seperti posisi node, node dengan sisa energi terbesar, dan jarak yang dihitung dalam tiga jarak yaitu jarak node menuju cluster center, jarak node menuju merge CH, dan jarak merge CH menuju sink. Hasil pengujian menunjukan bahwa dengan menggabungkan cluster (merge CH) pada transmisi data menuju sink pada protokol G-LEACH dapat menghasilkan masa hidup jaringan yang lebih lama pada seluruh operasi node, energi yang dibutuhkan pada semua node lebih rendah, dan lebih banyak paket data yang dikirim dan diterima oleh sink. Low Energy Adaptive Clustering Hierarchy (LEACH) is a routing algorithm in a cluster-based Wireless Sensor Network (WSN). LEACH selects a node as a cluster head (CH) whose responsibility is for communicating with sinks and collect data from the node members. The distribution of CH on LEACH, which is basically random, sometimes has a problem in remembering the probability formula on each round. This may make the selected CH on the edge of the area as well as generate energy waste because the pathway formed will be lengthy. Therefore, we would like to develop the G-LEACH routing protocol using a merge CH technique in one area (grid) with several relevant parameters, such as the position of the node, the node with the largest remaining energy, and the distance calculated in three distances: the distance of the node to the clustercenter, the distance of the node to the merge CH, and the distance of the merge CH to the sink. The test result showed that combining clusters (merge CH) in the data transmission to the sink in the G-LEACH protocol could produce a longer network life on all node operations, lower energy required for all nodes, and more data package sent and received by the sink.
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Et. al., Heba Hussain Hadi,. "Energy Efficient Routing Protocall By One Way Multi-Hope Sensor Nodes". Turkish Journal of Computer and Mathematics Education (TURCOMAT) 12, nr 7 (13.06.2021): 3401–10. http://dx.doi.org/10.17762/turcomat.v12i7.4540.
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Multi-hope is widely used for data aggregation and transmission in various applications. The resource availability determines the life time of a WSN. Sensor nodes are powered by a tiny battery that supplies the required energy for the sensor and transmitter. The residual energy available at any moment decides the fitness of the sensor node. The sensor node senses the environment and transmits the data to the sink. Efficient data transmission and aggregation with less energy consumption can prolong the lifetime of the sensor network. The sensor node that is inside the coverage area of the sink can directly transmit the data to sink in a single-hop transmission. The sensor node that is not inside the coverage area should transmit the data to the neighbor node which is in the coverage area of the sink. The data is then turn transmitted by the node close to it fall in multi-hop transmission involving a number of intermediate nodes to forward the data to the sink and consumes extra energy for the forwarding process. The formation clusters and data transmission of data by Cluster Heads (CH) can eliminate many nodes involved in the transmission of same data. Clusters are a group of self-organized nodes in a geographic location that can communicate among them. A node in a cluster with higher residual energy will be acting as CH and all other nodes in the cluster transmit the data to the CH. The CH transmits the aggregated data to the sink. The CH transmits the data to the sink either in single-hop transmission or multi-hop transmission. The cluster head consumes more energy than other nodes in the cluster as it is involved in aggregation and transmission process.
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Mote, Tushar S., i S. K. Jagtap. "Adaptive Threshold Residual Energy-Based Efficient Sensor Network Protocol (ATREEN)". Journal of Sensors 2023 (26.07.2023): 1–7. http://dx.doi.org/10.1155/2023/1629438.
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Wireless sensor network (WSN) hierarchical (clustering) routing involves the gathering of sensor nodes to form clusters in which sensor node communicates to cluster head (CH). The CH is responsible for data aggregation and forwarding collected data toward base station (BS). Energy expenditure in usual protocols becomes unequal because of clusters having diverse lengths. In this paper, we propose another new enhanced clustering protocol called adaptive threshold residual energy-based efficient sensor network protocol (ATREEN) for adaptive selection of CH in WSNs. In ATREEN, CHs are chosen by comparing threshold of node value with respect to distance between cluster member and CH, residual energy of sensor nodes, and position of sensor node with respect to BS. Simulation results show that ATREEN protocol extends network lifetime and stability with decline in energy dissipation compared to clustering protocols such as low-energy adaptive clustering hierarchy (LEACH), power-efficient gathering in sensor information systems (PEGASIS), and distributed energy-efficient clustering (DEEC) scheme for heterogeneous WSNs.
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Fallo, Kristoforus, i Budiman Baso. "Analisis Perbandingan Teknik Pemilihan Cluster Head Pada Wireless Sensor Network Berbasis Clustering Menggunakan Algoritma Routing Protocol LEACH dan G-LEACH". Journal of Information and Technology 3, nr 1 (27.02.2023): 1–5. http://dx.doi.org/10.32938/jitu.v3i1.3795.
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Wireless Sensor Network (WSN) is a series of wireless networks consisting of several nodes in a limited area. Low Energy Adaptive Clustering Hierarchy (LEACH) and Grid-Based Low Energy Adaptive Clustering Hierarchy (G-LEACH) methods are clustering methods used to collet data by clustering nodes in the WSN area. The clustering process for both methods is the same, namely by select node as the Cluster head (CH) whose job is to collet data from other nodes to the sink. The selection of CH is carried out in each round by taking into account the probability formula used and the largest the remaining energy at that node. This study aims to determine the quality comparison of CH selection techniques in clustering-based routing protocol on WSN. The result of the study show that the G-LEACH routing protocol has good quality CH selection techniques and a long network lifetime compared to LEACH but requires a long time to reach the CH selection process
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Gupta, Amit, Mahesh Motwani i J. L. Rana. "Cluster Formation and Maintenance Techniques for Mobile Adhoc Networks with Improved Quality of Service". International Journal of Emerging Technology and Advanced Engineering 11, nr 8 (19.08.2021): 97–110. http://dx.doi.org/10.46338/ijetae0821_12.
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— In an Adhoc Network, every node is mobile and self-contained. As these networks lack infrastructure, highly adaptive algorithms are required to deal with frequent mobility changes by member nodes as well as Cluster Head (CH) nodes. The weighted clustering algorithms contribute significantly to cluster-based routing. In these algorithms, the selection of cluster heads is the most important task. In weighted clustering methods, the selected CH did their best to serve the network. However, the CH may become overloaded due to the arrival of nodes greater than their desired threshold value. In this case, the CH can become a bottleneck as it is unable to cope with rapidly increasing loads which ultimately degrade the network performance. In this paper, we address three network issues (i) Member Node movement (ii) Cluster head Node movement, and (iii) Overload at the Cluster head node caused due to mobility of nodes. Our proposed method Cluster Formation and Maintenance Techniques for Mobile Adhoc Networks with Improved Quality of Service (CFMIQS) include various adaptive algorithms to provide solutions to deal with these network issues and improve network Quality of Service (QoS). The Simulated Results are compared with the K-means AODV algorithm, the results showed better Packet Delivery Fraction (PDF) and Throughput values. Keywords— Cluster partition, MANET, Primary Cluster head, QoS, Secondary Cluster head
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Khalifeh, Ala’, Husam Abid i Khalid A. Darabkh. "Optimal Cluster Head Positioning Algorithm for Wireless Sensor Networks". Sensors 20, nr 13 (3.07.2020): 3719. http://dx.doi.org/10.3390/s20133719.
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Wireless sensor networks (WSNs) are increasingly gaining popularity, especially with the advent of many artificial intelligence (AI) driven applications and expert systems. Such applications require specific relevant sensors’ data to be stored, processed, analyzed, and input to the expert systems. Obviously, sensor nodes (SNs) have limited energy and computation capabilities and are normally deployed remotely over an area of interest (AoI). Therefore, proposing efficient protocols for sensing and sending data is paramount to WSNs operation. Nodes’ clustering is a widely used technique in WSNs, where the sensor nodes are grouped into clusters. Each cluster has a cluster head (CH) that is used to gather captured data of sensor nodes and forward it to a remote sink node for further processing and decision-making. In this paper, an optimization algorithm for adjusting the CH location with respect to the nodes within the cluster is proposed. This algorithm aims at finding the optimal CH location that minimizes the total sum of the nodes’ path-loss incurred within the intra-cluster communication links between the sensor nodes and the CH. Once the optimal CH is identified, the CH moves to the optimal location. This suggestion of CH re-positioning is frequently repeated for new geometric position. Excitingly, the algorithm is extended to consider the inter-cluster communication between CH nodes belonging to different clusters and distributed over a spiral trajectory. These CH nodes form a multi-hop communication link that convey the captured data of the clusters’ nodes to the sink destination node. The performance of the proposed CH positioning algorithm for the single and multi-clusters has been evaluated and compared with other related studies. The results showed the effectiveness of the proposed CH positioning algorithm.
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L., Rajesh, i Mohan H. S. "Shuffled Shepherd Squirrel Optimization and Fractional LMS Model for In-Network Aggregation in Wireless Sensor Network". International Journal of Business Data Communications and Networking 18, nr 1 (1.01.2022): 1–20. http://dx.doi.org/10.4018/ijbdcn.309412.
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The wireless sensor network (WSN) is commonly based on small node collaboration. These nodes are specified by wireless communication, low price, and energy consumption. Moreover, the WSN can be utilized to compute pressure, temperature, as well as monitoring health, military supervision, and so on. A variety of WSN applications need to gather data from sensor nodes based on sink. In this paper, shuffled shepherd squirrel optimization (SSSOA) technique is devised for in-network aggregation in WSN. Here, the path is formulated from source node to destination through routing process, and source node broadcasts a packet concurrently to destination. The WSN is initiated, and the suitable cluster head (CH) is selected from all nodes. Consequently, CH is selected based on the developed shuffled shepherd squirrel optimization (SSSOA) method.
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Subramani, Neelakandan, Abbas Mardani, Prakash Mohan, Arunodaya Raj Mishra i Ezhumalai P. "A fuzzy logic and DEEC protocol-based clustering routing method for wireless sensor networks". AIMS Mathematics 8, nr 4 (2023): 8310–31. http://dx.doi.org/10.3934/math.2023419.
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<abstract> <p>Power-efficient wireless sensor network routing techniques (WSN). Clustering is used to extend WSNs' lifetimes. One node act as the cluster head (CH) to represent the others in communications. The member nodes are less important than the cluster hub (CH) in the clustering procedure. Fuzzy techniques based on clustering theory may provide evenly distributed loads. In this study, we provide a fuzzy-logic-based solution that factors in distance to base station (BS), number of nodes, remaining energy, compactness, distance to communicate within a cluster, number of CH, and remaining energy. Fuzzy clustering has a preliminary and final step. First, we select CH based on distance to the base station (BS), remaining node vigor, and node compactness. In the second phase, clusters are created by combining nodes that aren't already in a CH, using density, outstanding vigor, and detachment as limitations. The proposed solution increases load balancing and node longevity. This work provides a unique hybrid routing technique for forming clusters and managing data transfer to the base station. Simulation findings confirm the protocol's functionality and competence. Reduced energy use keeps network sensor nodes online longer. The framework outperforms Stable Election Protocol (SEP), hybrid energy-efficient distributed clustering (HEED), and Low Energy Adaptive Clustering Hierarchy (LEACH). Using the nodes' energy levels to create a grid pattern for the clusters gave four clusters. In addition, the proposed method has a 4347%, 41.46%, 39.26%, 37.57% and 35.67% reduction in average energy consumption when compared with the conventional algorithms. The proposed technologies could increase the network's lifetime, stability interval, packet transfer rate (throughput), and average energy. The suggested protocol is at least 50% better in every statistic that was looked at, such as network lifetime, stability interval, packet transmission rate (throughput), and average energy use.</p> </abstract>
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Devika, G., D. Ramesh i Asha Gowda Karegowda. "Analysis of Binary and Discrete Grey Wolf Optimization Algorithms Applied for Enhancing Performance of Energy Efficient Low Energy Adaptive Clustering Hierarchy". Journal of Computational and Theoretical Nanoscience 17, nr 9 (1.07.2020): 3850–59. http://dx.doi.org/10.1166/jctn.2020.8974.
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Wireless sensor networks (WSN) are a yield of advancement in information technology and the requirement of large-scale communication infrastructures. Routing of data via selected paths is a critical task in WSN as process need to be carried on under resource constraint situations. This route identification problem can be better handled by employing appropriate heuristic bio-inspired computational intelligence optimization method. The most frequently applied routing is hierarchical routing algorithm is Low Energy Adaptive Clustering Hierarchy (LEACH) algorithm which has limitations in identifying energy efficient inter and intra route communication, identification of number of cluster head (CH), an eminent node to communicate to CH and Base Station (BS), selection of CH, and computing residual energy level, etc. Hence, researchers are focusing on boosting the capability of LEACH clustering algorithm by applying heuristic bio-inspired computational intelligence optimization methods. The proposed work is an attempt in this direction through applying heuristic bio-inspired Grey Wolf Optimization algorithm (GWO) for improving the performance of LEACH algorithm. In this paper, focus is given to increase the overall network time by adapting two modifications to conventional algorithms (i) selection of vice cluster head (VCH) in addition to CH (VCH node will replace the CH when CH when CH node goes down due to unexpected reasons as sensor node work under critical and uninterruptable environments and (ii) selection of intra and inter relay nodes (intra relay node will enhance the life span during CH data gathering and inter relay node will further enhance the life span of CH by acting as a mediator between CH an BS). The Spyder-py3 tool is used to simulate the proposed algorithms, LEACH Binary Grey Wolf search based Optimization (LEACH-BGWO) and LEACH Discrete Grey Wolf search based Optimization (LEACH-DGWO) protocols. The proposed work is compared with cluster based LEACH algorithm, chain based power-efficient gathering in sensor information systems (PEGASIS) algorithm, bio-inspired GWO and Genetic Algorithm data Aggregation (GADA) LEACH protocols. The results prove that both proposed algorithms outperformed other conventional algorithms in terms of prolonged network lifespan and increased throughput. Among proposed algorithms LEACH-BGWO outperformed LEACH-DGWO
Rozprawy doktorskie na temat "CH NODE"
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SINGH, JOGINDER. "OPTIMIZED CLUSTERING APPROACH FOR WIRELESS SENSOR NETWORK". Thesis, 2017. http://dspace.dtu.ac.in:8080/jspui/handle/repository/15859.
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Wireless sensor network play an important role in today’s networks which are mainly focusing on automating the computing needs of the world. These networks can work better in an environment which is unattended and inaccessible. As such networks have constrained potentials such as battery power, radio transmission range, memory and processing hardware of the sensor nodes which makes them less robust in case of node failures, inefficient, poor scalability. One of the main unique features of WSN is that they have wireless connectivity among the small size sensor nodes which makes them work even in harsh conditions with limited human support. WSNs is a type of an ad-hoc networks that involves the large number of small, lightweight sensor nodes. Here, the energy of nodes is a critical issue in WSN because of limited battery life. There are some of the challenging issues in WSN like energy consumption, traffic load balancing, data aggregation, data redundancy, limited wireless communication range.
In this thesis, we have worked towards designing of new energy efficient clustering algorithms to achieve higher energy performance along with longer life span of the network in WSNs. we have proposed two new improved clustering algorithms for the purpose of efficient clustering analysis of data sets to offer high energy efficiency and reduced communication overheads. The first algorithm will solve the difficulty of finding the optimal number of clusters with their cluster centroids and arbitrarily shaped clusters set by uniting model and density based algorithms. It also presents an idea for estimating input parameters to minimize intra and inter-cluster distance between sensor nodes. The proposed hybrid algorithm reduces wireless data transmissions and increases the speed of transferring the accumulated data to the mobile sink node located at the cluster centroid that patrols by following the shortest path. The second algorithm presents a new idea for cluster formation phase and cluster head selection phase based on density of the sensor node. It not only finds the optimal number of clusters in every round, but also gives an idea of electing cluster head based on density using residual energy, average energy and distance from the location of cluster centroid. After cluster formation phase, all the member nodes convey their data to selected CH node during each round. The CH node aggregates the received data to remove duplicate number of packets so that the it can be communicated to static or mobile sink node in less time with higher transmission speed when the distance between them is minimal. This suggested algorithm guarantees uniform distribution of CH in the sensing field to preserve the energy of sensor nodes.
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Mentrup, Detlef. "Isothermal quantum dynamics: Investigations for the harmonic oscillator". Doctoral thesis, 2003. https://repositorium.ub.uni-osnabrueck.de/handle/urn:nbn:de:gbv:700-2003052613.
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Thermostated time evolutions are on a firm ground and widely used in classical molecular dynamics (MD) simulations. Hamilton´s equations of motion are supplemented by time-dependent pseudofriction terms that convert the microcanonical isoenergetic time evolution into a canonical isothermal time evolution, thus permitting the calculation of canonical ensemble averages by time averaging. However, similar methods for quantum MD schemes are still lacking. Given the rich dynamical behavior of ultracold trapped quantum gases depending on the value of the s-wave scattering length, it is timely to investigate how classical thermostating methods can be combined with powerful approximate quantum dynamics schemes to deal with interacting quantum systems at finite temperature. In this work, the popular method of Nose and Hoover to create canonically distributed positions and momenta in classical MD simulations is generalized to a genuine quantum system of infinite dimensionality. We show that for the quantum harmonic oscillator, the equations of motion in terms of coherent states may be modified in a Nose-Hoover manner to mimic the coupling of the system to a thermal bath and create a quantum canonical ensemble. The method is developed initially for a single particle and then generalized to the case of an arbitrary number of identical quantum particles, involving entangled distribution functions. The resulting isothermal equations of motion for bosons and fermions contain additional terms leading to Bose-attraction and Pauli-blocking, respectively. Questions of ergodicity are discussed for different coupling schemes. In the many-particle case, the superiority of the Nose-Hoover technique to a Langevin approach is demonstrated. In addition, the work contains an investigation of the Grilli-Tosatti thermostating method applied to the harmonic oscillator, and calculations for quantum wavefunctions moving with a time-invariant shape in a harmonic potential.
Książki na temat "CH NODE"
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Jörg, Kammerhofer. Part II Approaches, Ch.20 International Legal Positivism. Oxford University Press, 2016. http://dx.doi.org/10.1093/law/9780198701958.003.0021.
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This chapter explores the role of positivism in international law, noting that the term ‘positivism’ itself has many connotations, most of which muddy an already neglected—yet strikingly pervasive—approach to international law. On that note, the chapter explores the differences (and overlaps) between positivism and formalism; then, it shows how radically different modern, philosophically- and jurisprudentially-informed forms of international legal positivism are, how little they are touched by the constant attack on the positivist–voluntarist straw man, and how unfair it is to lump them together with unthinking ‘positivists’:. Following these arguments is a reconstruction of the Neo-Hartian Socio-Psychologico-Linguistic school of positivism.
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Wouter, Werner, i Gordon Geoff. Part II Approaches, Ch.25 Kant, Cosmopolitanism, and International Law. Oxford University Press, 2016. http://dx.doi.org/10.1093/law/9780198701958.003.0026.
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This chapter explores the way in which Kantian ideas have been adopted and transformed in contemporary international law and international theory, with the twofold aim of introducing some core topics on Kantian philosophy, cosmopolitanism, and international law, as well as demonstrating the importance of acknowledging different forms of cosmopolitanism at work in international law, thereby shedding new light on the ‘forgotten’ tradition of innate cosmopolitanism. The work of Kant not only occupies an important place in the history of ideas in international legal theory; his work also constitutes an enduring source of inspiration for widely diverging contemporary approaches to international law. On that note, the chapter references four core Kantian ideas incorporated in contemporary cosmopolitan thinking: the categorical imperative, the roughly contractual notion of a federation of free republics, the conception of a cosmopolitan right of hospitality, and the idea of an innate cosmopolitanism.
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Benedict, Kingsbury, Donaldson Megan i Vallejo Rodrigo. Part II Approaches, Ch.26 Global Administrative Law and Deliberative Democracy. Oxford University Press, 2016. http://dx.doi.org/10.1093/law/9780198701958.003.0027.
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This chapter attempts to bring ‘global administrative law’ (GAL) and democracy into conversation. It addresses two separate observations: first, that democracy currently lacks the tools to respond to the globalization and diffusion of political authority; and secondly, that GAL is not presently democratic—it has no room for democratic concerns in its emerging norms. As such, the chapter aims to give an overview of GAL and some of its contributions to international legal theory; explore the way in which GAL’s focus on innumerable capillary-level sites of power may open promising terrain for the instantiation of democracy beyond the state; consider how work on GAL can be enhanced by engaging with, and drawing ideas from, work on deliberative democracy; and note the rising impact and future potential of democratic striving in the practice of institutional entrepreneurship and GAL lawyering.
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Notebooks, Amirlove. Note d'amour � Ma Ch�rie: Cadeaux de Saint Valentin Pour Lui / Elle Carnet de Notes Lign�, 6 X 9. Independently Published, 2020.
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Note to Users of IRM 7751, (Now Revised to IRM 7.8.2.), Enclosed are 4 IRM Transmittals: IRM 7.8.2 Chapters (CH) 2, 19, 25, and 28 (Revised December 97). [S.l: s.n., 1998.
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Edition, Mon Petit Carnet. Chocolat Mon Plus Grand P�ch�: Carnet de Note Mon Petit Carnet - Carnet de Recette de Cuisine - Livre de Recueil Pour Cuisinier, P�tissier - 100 Pages Vierges - Format 6x9 Po - 15,24 Cm X 22,86 Cm - Made in France. Independently Published, 2020.
Znajdź pełny tekst źródłaCzęści książek na temat "CH NODE"
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Muñoz-Viñas, Salvador. "A note on CH practices". W A Theory of Cultural Heritage, 61–66. London: Routledge, 2023. http://dx.doi.org/10.4324/9781003288121-5.
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bin Talal, El Hassan. "Key Note Address". W Global Sustainability, 1–4. Weinheim, FRG: Wiley-VCH Verlag GmbH & Co. KGaA, 2005. http://dx.doi.org/10.1002/3527604251.ch.
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Garbani-Nerini, Elide, Elena Marchiori i Lorenzo Cantoni. "Destinations and Data State-of-the-Art in Switzerland and Liechtenstein". W Information and Communication Technologies in Tourism 2022, 200–212. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-94751-4_18.
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AbstractThis research investigates the state of the art among Switzerland (CH)’s and Liechtenstein (FL)’s destinations, intended here as Destination Marketing Organizations (DMOs), when it comes to their relationship with data: what data are collected, how they are stored, analyzed and what impact they have on the destination. This study aims at bringing insights into smart tourism studies as a key aspect of the debate is how DMOs deal with data. Based on a survey performed with CH’s and FL’s DMOs and related stakeholders, results suggested that there are common conceptual nodes shared by practitioners when it comes to defining smart destinations. However, when it comes to data-related practices (data collection, storage, analysis and sharing) DMOs have very different processes in place. There are organizations that collect but do not extensively analyze data, while others are still not so keen on sharing their data with the whole destination ecosystem. Furthermore, organizations’ decision-making processes appear to be based to some extent on data, especially when it comes to (digital) marketing initiatives and campaigns, although behaviors are quite different also in this area. Destination managers might benefit from this paper as the study shows how to investigate data-related practices of an organization. This type of analysis could allow an assessment of the situation and an understanding of the direction in which the organization might move forward.
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K P, Sampoornam, Hemavikasini S, Vidhya S, Vakula V i Dharani S. "Efficient Cluster Head Selection in WSN Using Secure Mobility Cluster Based Algorithm". W Intelligent Systems and Computer Technology. IOS Press, 2020. http://dx.doi.org/10.3233/apc200147.
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Wireless Sensor Networks (WSNs) are widely adopted by various civilian/military applications for implementing real-time monitoring or long-term surveillance task. Considering sensor nodes with mobility has emerged as a major application in environmental monitoring or surveillance. Due to the limited battery lifetime, the network in the deployed region is divided into clusters and the clusters are controlled by their Cluster Heads (CH). But selecting CH in WSNs (considering the network with both static and mobility nodes) is a challenging task because security is significant. To prevent the malicious sensor node from becoming CH, Secure Mobility Cluster Based Algorithm (SMCBA) is proposed. This algorithm considers only static node among mobility node for selecting CH with efficient parameters such as trust criteria, selection time and mobility. The simulation results show that the proposed algorithm works effectively compared with the existing clustering algorithms.
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Bhardwaj, Reeta, Nidhi Saini, Dinesh Kumar i Rajeev Kumar. "A Modified Approach of I-LEACH Algorithm for Cluster-head Selection in Wireless Sensor Networks". W Emerging Trends In Engineering And Management, 27–36. Wyd. 2023. Soft Computing Research Society, 2023. http://dx.doi.org/10.56155/978-81-955020-3-5-04.
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Although Wireless Microsensor Networks have been widely employed for numerous security related applications, the lifespan of microsensor nodes and energy efficiency have always been a challenge. LEACH protocol has proved to be a milestone in this field by providing the methodology of forming clusters of the sensor nodes in the network. Moreover, each cluster has a cluster head (CH) node which needs to be selected strategically for desirable network performance. This paper presents a variant for LEACH protocol for CH selection by using an optimization technique called Simulated Raindrop algorithm that ameliorates lifespan of microsensor nodes, throughput and energy efficacy in the network. The CH nodes are well-dispersed in the network to reduce energy loss of microsensor nodes for data transmission as well as reception and successful data packet delivery to base station. The results are analyzed and compared to LEACH-C, LEACH-GA and I-LEACH protocol on the basis of network lifetime, throughput and remaining energy in the network have surpassed them.
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Khan, Bilal Muhammad, i Rabia Bilal. "Fuzzy-Topsis-Based Cluster Head Selection in Mobile Wireless Sensor Networks". W Handbook of Research on Recent Developments in Intelligent Communication Application, 312–43. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-1785-6.ch012.
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One of the critical and vital parameter of Wireless Sensor Networks (WSNs) is its lifetime. There are various methods to increase WSN lifetime, clustering technique is one of them. In clustering, selection of desired percentage of Cluster Head (CHs) is performed among the sensor nodes (SNs). Selected CHs are responsible to collect data from its member nodes, aggregates the data and finally send to the sink. In this chapter, Fuzzy-TOPSIS techniques based on multi criteria decision making to choose CH efficiently and effectively to maximize the WSN lifetime are presented. These five criteria includes; residual energy, node energy consumption rate, number of neighbor nodes, average distance between neighboring nodes and distance from sink. Threshold based intra-cluster and inter-cluster multi-hop communication mechanism is used to decrease energy consumption. Moreover impact of node density and different type mobility strategies are presented in order to investigate impact over WSN lifetime.
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Khan, Bilal Muhammad, i Rabia Bilal. "Fuzzy-Topsis-Based Cluster Head Selection in Mobile Wireless Sensor Networks". W Sensor Technology, 596–627. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-2454-1.ch029.
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One of the critical and vital parameter of Wireless Sensor Networks (WSNs) is its lifetime. There are various methods to increase WSN lifetime, clustering technique is one of them. In clustering, selection of desired percentage of Cluster Head (CHs) is performed among the sensor nodes (SNs). Selected CHs are responsible to collect data from its member nodes, aggregates the data and finally send to the sink. In this chapter, Fuzzy-TOPSIS techniques based on multi criteria decision making to choose CH efficiently and effectively to maximize the WSN lifetime are presented. These five criteria includes; residual energy, node energy consumption rate, number of neighbor nodes, average distance between neighboring nodes and distance from sink. Threshold based intra-cluster and inter-cluster multi-hop communication mechanism is used to decrease energy consumption. Moreover impact of node density and different type mobility strategies are presented in order to investigate impact over WSN lifetime.
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Parwekar, Pritee. "SGO A New Approach for Energy Efficient Clustering in WSN". W Sensor Technology, 716–34. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-2454-1.ch034.
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In wireless sensor networks (WSNs), consumption of energy is the major challenging issue. If the data is transmitted directly from the node to the base station, it leads to more transmissions and energy consumed also increases if the communication distance is longer. In such cases, to reduce the longer communication distances and to reduce the number of transmissions, a clustering technique is employed. Another way to reduce the energy consumed is to reduce the transmission from node to CH or from CH to BS. Reducing the transmission distance is a NP-Hard problem. So, optimization techniques can be used effectively to solve such problems. In this article, is the implementation of a social group optimization (SGO) to reduce the transmission distance and to allow the nodes to consume less energy. The performance of SGO is compared with GA and PSO and the results show that SGO outperforms in terms of fitness and energy.
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Acharya, Sasmita, i C. R. Tripathy. "A Fuzzy Knowledge Based Fault Tolerance Mechanism for Wireless Sensor Networks". W Sensor Technology, 679–97. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-2454-1.ch032.
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Wireless Sensor Networks (WSNs) are the focus of considerable research for different applications. This paper proposes a Fuzzy Knowledge based Artificial Neural Network Routing (ANNR) fault tolerance mechanism for WSNs. The proposed method uses an exponential Bi-directional Associative Memory (eBAM) for the encoding and decoding of data packets and application of Intelligent Sleeping Mechanism (ISM) to conserve energy. A combination of fuzzy rules is used to identify the faulty nodes in the network. The Cluster Head (CH) acts as the data aggregator in the network. It applies the fuzzy knowledge based Node Appraisal Technique (NAT) in order to identify the faulty nodes in the network. The performance of the proposed ANNR is compared with that of Low-Energy Adaptive Clustering Hierarchy (LEACH), Dual Homed Routing (DHR) and Informer Homed Routing (IHR) through simulation.
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Lekhraj, Alok Kumar, Avjeet Singh i Anoj Kumar. "Load Balanced Clustering in WSN using MADM Approaches". W Recent Developments in Artificial Intelligence and Communication Technologies, 80–110. BENTHAM SCIENCE PUBLISHERS, 2022. http://dx.doi.org/10.2174/9781681089676122010007.
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Over the last several decades, wireless sensor networks have grabbed a lot ofattention because of their wide range of applications in scientific communities as wellas industrial aspects. In WSN, sensor nodes are created with very limited resources,imposing energy constraints. Therefore, it is important to design a less energyconsuming,ascendible and power-efficient approach by selecting the optimal clusterheads (CHs) to enhance the life of these networks. Clustered sensor network is amethod to optimize the power consumption in the network, which greatly affects theperformance of the networks. In this article, we looked at clustering and routing issuesby employing intelligent optimization techniques by considering the maximumattribute of the wireless sensor networks (WSN), which are conflicting in nature. Theefficiency of WSN mainly depends upon the conflicting attributes, like residual energy,CH to base station distance, normal node to CH distance, etc. In this paper, multiattributedecision making (MADM) technique is considered for choosing the optimalCHs, so that energy consumption of the nodes is minimized and lifetime of the networkcan be maximized. The proposed approach is compared with other approaches likeLEACH, HEED, etc. Results verified that the proposed algorithm is outmatched incomparison to existing algorithms.
Streszczenia konferencji na temat "CH NODE"
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Anees, Junaid, i Hao-Chun Zhang. "Thermal entropy based hesitant fuzzy linguistic term set analysis in energy efficient opportunistic clustering". W 7th International Conference on Natural Language Computing (NATL 2021). Academy and Industry Research Collaboration Center (AIRCC), 2021. http://dx.doi.org/10.5121/csit.2021.112010.
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Limited energy resources and sensor nodes’ adaptability with the surrounding environment play a significant role in the sustainable Wireless Sensor Networks. This paper proposes a novel, dynamic, self-organizing opportunistic clustering using Hesitant Fuzzy Linguistic Term Analysis- based Multi-Criteria Decision Modeling methodology in order to overcome the CH decision making problems and network lifetime bottlenecks. The asynchronous sleep/awake cycle strategy could be exploited to make an opportunistic connection between sensor nodes using opportunistic connection random graph. Every node in the network observe the node gain degree, energy welfare, relative thermal entropy, link connectivity, expected optimal hop, link quality factor etc. to form the criteria for Hesitant Fuzzy Linguistic Term Set. It makes the node to evaluate its current state and make the decision about the required action (‘CH’, ‘CM’ or ‘relay’). The simulation results reveal that our proposed scheme leads to an improvement in network lifetime, packet delivery ratio and overall energy consumption against existing benchmarks.
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Khalifeh, Ala', Husam Abid i Khalid A. Darabkh. "Improving Energy Conservation Level in WSNs by Modifying CH Node Location". W 2020 Fifth International Conference on Fog and Mobile Edge Computing (FMEC). IEEE, 2020. http://dx.doi.org/10.1109/fmec49853.2020.9144975.
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Hendrickx, E., A. Tritchkov, K. Sakajiri, Y. Granik, M. Kempsell i G. Vandenberghe. "Hyper-NA imaging of 45nm node random CH layouts using inverse lithography". W SPIE Advanced Lithography. SPIE, 2008. http://dx.doi.org/10.1117/12.771961.
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Carvalho, Graziela Couto de, Heloisa Helena Gonçalves Rengel, Barbara Barbosa Monteiro, Larissa Scarabucci Venezian, Aline Campos Oliveira Mello i Fábio Francisco Oliveira Rodrigues. "AXILLARY LYMPH NODE CLIP PLACEMENT AND RESECTION AT SURGERY: A SINGLE-CENTER STUDY". W Brazilian Breast Cancer Symposium 2022. Mastology, 2022. http://dx.doi.org/10.29289/259453942022v32s2072.
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Objective: This study aims to identify the characteristics of patients who underwent axillary lymph node clipping (ALC) and determine the detection rate with sentinel node biopsy (SNB). Methods: This is a retrospective study with a review of medical records, including patients who were submitted to ALC from 2018 to 2021 and who underwent neoadjuvant chemotherapy (CH) or upfront surgery. In patients with SNB, the clipped node was marked with Technetium-99m before surgery. Results: We identified 13 patients who underwent ALC at diagnosis: 8 were submitted to SNB and 5 to axillary dissection without SNB (4 due to poor response to CH, 1 due to lobular histology with upfront surgery). The mean age was 54 years (38% <50 years). The clinical staging was: 12 with cT2cN1 — IIB and 1 with cT3cN2 — IIIA. Concerning tumor characteristics, 12 (92%) patients had ductal histology and 1 lobular; 3 patients had triple-negative disease (23%), 8 patients had luminal disease (61%), and 2 patients had triple-positive disease (15%). In 4 of the 8 patients who underwent SNB, the clip was identified in the image after surgery (2) or in the frozen section (2), and in 4 patients, no information regarding the localization of the clip was obtained in the records regarding the surgery. However, in the follow-up images, the axillary clip was not identified, presuming that it was removed. Considering the patients who did SNB, the detection rate was 50%. Conclusion: According to previous studies, ALC at the time of diagnosis is a useful tool to guide targeted axillary dissection, reducing the false-negative rate (FNR) of SNB after CH. It is important that the clip removal check is performed. Our results reflect that this verification is not always performed, which may have reduced identification rates. However, this study encourages further prospective studies to be carried out, with standardization of techniques for clip identification, improving detection rates, and reducing FNR of SNB in these patients.
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Tong, Timothy, Mohsen Abou-Ellail, Yuan Li i Karam R. Beshay. "Numerical Computation of Reacting Flow in Porous Burners With an Extended CH4-Air Reaction Mechanism". W ASME 2004 Heat Transfer/Fluids Engineering Summer Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/ht-fed2004-56012.
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The present paper presents, numerical computations for flow, heat transfer and chemical reactions in an axisymmetric inert porous burner. The porous media re-radiate the heat absorbed from the gaseous combustion products by convection and conduction. In the present work, the porous burner species mass fraction source terms are computed from an ‘extended’ reaction mechanism, controlled by chemical kinetics of elementary reactions. The porous burner has mingled zones of porous/nonporous reacting flow, i.e. the porosity is not uniform over the entire domain. Therefore, it has to be included inside the partial derivatives of the transport governing equations. Finite-difference equations are obtained by formal integration over control volumes surrounding each grid node. Up-wind differencing is used to insure that the influence coefficients are always positive to reflect the real effect of neighboring nodes on a typical central node. Finite-difference equations are solved, iteratively, for U, V, p’ (pressure correction), enthalpy and species mass fractions, utilizing a grid of (60×40) nodes. The sixty grid nodes in the axial direction are needed to resolve the detailed structure of the thin reaction zone inside the porous media. The porous burner uses a premixed CH4-air mixture, while its radiating characteristics are computed numerically, using a four-flux radiation model. Sixteen species are included, namely CH4, CH3, CH2, CH, CH2O, CHO, CO, CO2, O2, O, OH, H2, H, H2O, HO2, H2O2, involving 49 chemical reaction equations. It was found that 900 iterations are sufficient for complete conversion of the computed results with errors less than 0.1%. The computed temperature profiles of the gas and the solid show that, heat is conducted from downstream to the upstream of the reaction zone. Most stable species, such as H2O, CO2, H2, keep increasing inside the reaction zone staying appreciable in the combustion products. However, unstable products, such as HO2, H2O2 and CH3, first increase in the preheating region of the reaction zone, they are then consumed fast in the post-reaction zone of the porous burner. Therefore, it appears that their important function is only to help the chemical reactions continue to their inevitable completion of the more stable combustion products.
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Panful, Benjamin, i Xie Zhibin. "A Study of Energy Efficiency in Wireless Sensor Networks". W 28th iSTEAMS Multidisciplinary Research Conference AIUWA The Gambia. Society for Multidisciplinary and Advanced Research Techniques - Creative Research Publishers, 2021. http://dx.doi.org/10.22624/aims/isteams-2021/v28n3p9.
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The wireless sensor networks (WSNs) field is one of the emerging and fast-growing fields in the scientific world. This has brought about the development of low-cost, and multifunctional sensor nodes for easy and secure dissemination of information. Nonetheless, the problem of sensor nodes running out of energy quickly has been an issue. Many energyefficient routing algorithms have been proposed to solve this problem and preserve the longevity of the network. Most of the recent papers have shown so many protocols mainly designed to minimize energy consumption in the network but there are some limitations with regards to the area of operation and the optimization decisions. This paper proposes an Energy Efficiency Hierarchical Routing Technique (EEHRT) which is based on LEACH protocol to extend the lifespan of a WSN. In this work, the proposed Energy Efficient Hierarchical Routing Technique selects cluster heads based on the prediction of transmission energy through the shortest distance to the base station. Our approach rotates the role of Cluster Heads (CHs), and optimizes the CH selection by the prediction of energy transmission in every round and aggregating data before transmission to the BS. The important features which include member nodes formation and rotation, cluster head selection and rotation, and cluster optimization of our proposed hierarchical routing technique in transmitting data to the base station are analyzed and emphasized. Keywords: Wireless Sensor Network, Base Station, Member Node, Clustering, LEACH, Hierarchy Proceedings Reference Format Benjamin Panful & Xie Zhibin (2021): Rural Women’s Access to Land and its Implications for Empowerment in Nigeria: The Case of Ilorin East Local Government Area, Kwara State, Nigeria. Proceedings of the 28th iSTEAMS Intertertiary Multidisciplinary Conference. American International University West Africa, The Gambia. Series 28, Vol 3 October 2021. Pp 105-120 www.isteams.net/gambia2021. DOI - https://doi.org/
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Tong, Timothy W., Mohsen M. M. Abou-Ellail, Yuan Li i Karam R. Beshay. "Numerical Simulation of Reacting Flows in Radiant Porous Burners". W ASME 2005 Summer Heat Transfer Conference collocated with the ASME 2005 Pacific Rim Technical Conference and Exhibition on Integration and Packaging of MEMS, NEMS, and Electronic Systems. ASMEDC, 2005. http://dx.doi.org/10.1115/ht2005-72008.
Pełny tekst źródłaStreszczenie:
The present paper presents, numerical computations for flow, heat transfer and chemical reactions in an axisymmetric inert porous burner. The porous media re-radiate the heat absorbed from the gaseous combustion products by convection and conduction. In the present work, the porous burner species mass fraction source terms are computed from an ‘extended’ reaction mechanism, controlled by chemical kinetics of elementary reactions. The porous burner has mingled zones of porous/nonporous reacting flow, i.e. the porosity is not uniform over the entire domain. Therefore, it has to be included inside the partial derivatives of the transport governing equations. Finite-difference equations are obtained by formal integration over control volumes surrounding each grid node. Up-wind differencing is used to insure that the influence coefficients are always positive to reflect the real effect of neighboring nodes on a typical central node. Finite-difference equations are solved, iteratively, for U, V, p’ (pressure correction), enthalpy and species mass fractions, utilizing a fine grid of (80×60) nodes. The eighty grid nodes in the axial direction are needed to resolve the detailed structure of the thin reaction zone inside the porous media. The radial grid is extended inside the annular solid wall of the porous burner, to compute the wall temperature. The porous burner uses a premixed CH4-air mixture, while its radiating characteristics are computed numerically, using a four-flux radiation model. Sixteen species are included, namely CH4, CH3, CH2, CH, CH2O, CHO, CO, CO2, O2, O, OH, H2, H, H2O, H2O, H2O2, involving 49 chemical reaction equations. It was found that 1000 iterations are sufficient for complete conversion of the computed results with errors less than 0.1%. The computed temperature profiles of the gas and the solid show that, heat is conducted from downstream to the upstream of the reaction zone. Most stable species, such as H2O, CO2, H2, keep increasing inside the reaction zone staying appreciable in the combustion products. However, unstable products, such as HO2, H2O2 and CH3, first increase in the preheating region of the reaction zone, they are then consumed fast in the post-reaction zone of the porous burner. Therefore, it appears that their important function is only to help the chemical reactions continue to their inevitable completion of the more stable combustion products.
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Saleh, A. A., A. M. Farag, S. F. Bottoms, E. F. Mammen, M. Hosni i A. Ali. "SELECTED HEMOSTASIS PARAMETERS IN PREGNANCY AND HYPERTENSION". W XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644284.
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Patients with preeclampsia are believed to have a state of compensated DIC, and especially the differential diagnosis between preeclampsia and chronic hypertension with pregnancy can be difficult. Selected hemostasis parameters were analyzed in 50 women with preeclampsia (P), 50 matched normal pregnant women (N), 14 women with known hypertensionand pregnancy (CH) and 13 persons with known chronic hypertension and superimposed preeclampsia (CH + P). None of the patients had clinical evidence of DIC. Platelet counts, mean platelet volume, antithrombin III, α2 antiplasmin and fibrinogen activities and fibronectin were assayed. The following data wereThese data, together with higherlevels of fibrinopeptide A, platelet factor 4, 3 thromboglobulin and D-dimer in the P group suggests increased intravascular coagulation in preeclampsia. Fibronectin levels were markedly elevated only in the patient groups with preeclampsia. Discriminant function analysis of FN values between the groups revealed a78% diagnostic accuracy for Palone and 74% accuracy for CH + P
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Ali Adem, Mohammed. "Energy Optimization of Wireless Sensor Network Using Neuro-Fuzzy Algorithms". W LatinX in AI at Neural Information Processing Systems Conference 2019. Journal of LatinX in AI Research, 2019. http://dx.doi.org/10.52591/lxai2019120814.
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Wireless sensor network (WSN) is one of the recent technologies in communication and engineering world to assist various civilian and military applications. They are deployed remotely in sever environment which doesn’t have an infrastructure. Energy is a limited resource that needs efficient management to work without any failure. Energy efficient clustering of WSN is the ultimate mechanism to conserve energy for longtime. The major objective of this research is to efficiently consume energy based on the Neuro-Fuzzy approach particularly adaptive Neuro fuzzy inference system (ANFIS). The significance of this study is to examine the challenges of energy efficient algorithms and the network lifetime on WSN so that they can assist several applications. Clustering is one of the hierarchical based routing protocols, which manage the communication between sensor nodes and sink via Cluster Head (CH), CH is responsible to send and receive information from multiple sensor nodes and multiple base stations (BS). There are various algorithms that can efficiently select appropriate CH and localize the membership of cluster with fuzzy logic classification parameters to minimize periodic clustering which consumes more energy and we have applied neural network learning algorithm to learn various patterns based on the fuzzy rules and measured how much energy has saved from random clustering. Finally, we have compared to our Neuro-Fuzzy logic and consequently demonstrated that our Neuro-Fuzzy model outperforms than random model.
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Foley, C. W., I. Chterev, J. Seitzman i T. Lieuwen. "High Resolution PIV and CH-PLIF Measurements and Analysis of a Shear Layer Stabilized Flame". W ASME Turbo Expo 2015: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/gt2015-43387.
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Understanding the mechanisms and physics of flame stabilization and blowoff of premixed flames is critical towards the design of high velocity combustion devices. In the high bulk flow velocity situation typical of practical combustors, the flame anchors in shear layers where the local flow velocities are much lower. Within the shear layer, fluid strain deformation rates are very high and the flame can be subjected to significant stretch levels. The main goal of this work was to characterize the flow and stretch conditions that a premixed flame experiences in a practical combustor geometry and to compare these values to calculated extinction values. High resolution, simultaneous PIV and CH-PLIF measurements are used to capture the flame edge and near-field stabilization region. When approaching lean limit extinction conditions, we note characteristic changes in the stretch and flow conditions experienced by the flame. Most notably, the flame becomes less critically stretched when fuel/air ratio is decreased. However, at these lean conditions, the flame is subject to higher mean flow velocities at the edge, suggesting less favorable flow conditions are present at the attachment point of the flame as blowoff is approached. These measurements suggest that blowoff of the flame from the shear layer is not directly stretch extinction induced, but rather the result of an imbalance between the speed of the flame edge and local tangential flow velocity.