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Reinforcement learning (RL) is currently used in various real-life applications. RL-based solutions have the potential to generically address problems, including the ones that are difficult to solve with heuristics and meta-heuristics and, in addition, the set of problems and issues where some intelligent or cognitive approach is required. However, reinforcement learning agents require a not straightforward design and have important design issues. RL agent design issues include the target problem modeling, state-space explosion, the training process, and agent efficiency. Research currently addresses these issues aiming to foster RL dissemination. A BAM model, in summary, allocates and shares resources with users. There are three basic BAM models and several hybrids that differ in how they allocate and share resources among users. This paper addresses the issue of an RL agent design and efficiency. The RL agent's objective is to allocate and share resources among users. The paper investigates how a BAM model can contribute to the RL agent design and efficiency. The AllocTC-Sharing (ATCS) model is analytically described and simulated to evaluate how it mimics the RL agent operation and how the ATCS can offload computational tasks from the RL agent. The essential argument researched is whether algorithms integrated with the RL agent design and operation have the potential to facilitate agent design and optimize its execution. The ATCS analytical model and simulation presented demonstrate that a BAM model offloads agent tasks and assists the agent's design and optimization.

Artificial intelligence (AI) has been used in various areas to support system optimization and find solutions where the complexity makes it challenging to use algorithmic and heuristics. Case-based Reasoning (CBR) is an AI technique intensively exploited in domains like management, medicine, design, construction, retail and smart grid. CBR is a technique for problem-solving and captures new knowledge by using past experiences. One of the main CBR deployment challenges is the target system modeling process. This paper presents a straightforward methodological approach to model CBR-based applications using the concepts of abstract and concrete models. Splitting the modeling process with two models facilitates the allocation of expertise between the application domain and the CBR technology. The methodological approach intends to facilitate the CBR modeling process and to foster CBR use in various areas outside computer science., {"references":["Raouf Boutaba, Mohammad A. Salahuddin, Noura Limam, Sara Ayoubi, Nashid Shahriar, Felipe Estrada-Solano, and Oscar M. Caicedo. A Comprehensive Survey on Machine Learning for Networking: Evolution, Applications and Research Opportunities. Journal of Internet Services and Applications, 9(1):16, June 2018.","Amina Adadi and Mohammed Berrada. Peeking Inside the Black-Box: A Survey on Explainable Artificial Intelligence (XAI). IEEE Access, 6:52138– 52160, 2018.","Mohammad Saeid Mahdavinejad, Mohammadreza Rezvan, Mohammadamin Barekatain, Peyman Adibi, Payam Barnaghi, and Amit P. Sheth. Machine Learning for Internet of Things Data Analysis: A Survey. Digital Communications and Networks, 4(3):161–175, August 2018.","Richard S. Sutton and Andrew G. Barto. Reinforcement Learning: An Introduction. Adaptive computation and machine learning. MIT Press, Cambridge, Mass., nachdr. edition, 1998.","German I. Parisi, Ronald Kemker, Jose L. Part, Christopher Kanan, and Stefan Wermter. Continual Lifelong Learning with Neural Networks: A Review. Neural Networks, 113:54–71, May 2019.","Agnar Aamodt and Enric Plaza. Case-based reasoning: Foundational issues, methodological variations, and system approaches. AI Commun., 7(1):39–59, March 1994.","Petra Perner. Case-Based Reasoning and the Statistical Challenges II. In Dr. Aleksandra Gruca, Tadeusz Czachórski, and Stanisław Kozielski, editors, Man-Machine Interactions 3, Advances in Intelligent Systems and Computing, pages 17–38, Cham, 2014. Springer International Publishing.","Ali Boukehila and Nora Taleb. Case-Based Approach to Detect Emergence. In Proceedings of the 2019 3rd International Conference on Big Data Research, pages 98–102, 2019.","Malik Jahan Khan, Hussain Hayat, and Irfan Awan. Hybrid Case-Base Maintenance Approach for Modeling Large Scale Case-Based Reasoning Systems. Human-centric Computing and Information Sciences, 9(1):9, March 2019.","Arkadiusz Weglarz and Paweł Gilewski. Application of CBR Systems in the Process of Energy Retrofit of Single-Family Detached Houses. MATEC Web of Conferences, 196:02033, 2018. Publisher: EDP Sciences.","Lukasz Osuszek and Stanisław Stanek. Case Based Reasoning as an Element of Case Processing in Adaptive Case Management Systems. Annals of Computer Science and Information Systems, 6:217–223, 2015.","Yikun Su, Shijing Yang, Kangning Liu, Kaicheng Hua, and Qi Yao. Developing A Case-Based Reasoning Model for Safety Accident Pre-Control and Decision Making in the Construction Industry. International Journal of Environmental Research and Public Health, 16(9), May 2019.","Nabanita Choudhury and Shahin Ara Begum. A Survey on Case-based Reasoning in Medicine. In Proceedings of the International Journal of Advanced Computer Science and Applications, volume 7 of 8, pages 136–144, 2016.","Hugo Lopez-Fernandez, Florentino Fernandez Riverola, Miguel Reboiro-Jato, Daniel Glez-Pena, and Jose R. Mendez. Using CBR as Design Methodology for Developing Adaptable Decision Support Systems. Efficient Decision Support Systems - Practice and Challenges From Current to Future, 2011.","Flávio G. Calhau and Joberto S B Martins. A Electric Network Reconfiguration Strategy with Case-Based Reasoning for the Smart Grid. In Proceedings of the VIII Brazilian Conference on Intelligent Systems (BRACIS), pages 1–6, Salvador, Brazil, October 2019.","Eliseu M. Oliveira, Rafael F. Reale, and Joberto S. B. Martins. Evaluating CBR Similarity Functions for BAM Switching in Networks with Dynamic Traffic Profile. In Proceedings of the V International Workshop on ADVANCEs in ICT Infrastructure and Services, pages 1–7, Paris, January 2017.","Aldo Von Wangenheim, Christiane Gresse von Wangenheim, and Thiago Rateke. Raciocínio Baseado em Casos - 2ª ed. Revisada e Atualizada. 07 2013.","I. Watson. Case-Based Reasoning Is a Methodology Not a Technology. Knowledge-Based Systems, 12(5):303–308, October 1999.","Zhaoyu Zhai, José-Fernán Martínez Ortega, Victoria Beltran, and Néstor Lucas Martínez. An Associated Representation Method for Defining Agricultural Cases in a Case-Based Reasoning System for Fast Case Retrieval. Sensors, 19(23):5118, January 2019.","Ralph Bergmann and Klaus-Dieter Althoff. Methodology for Building CBR Applications. Case-Based Reasoning Technology, pages 299–326, 1998.","Rosina Weber, Jason M. Proctor, Ilya Waldstein, and Andres Kriete. CBR for Modeling Complex Systems. In Case-Based Reasoning Research and Development, pages 625–639, August 2005.","Jean-Baptiste Lamy, Boomadevi Sekar, Gilles Guezennec, Jacques Bouaud, and Brigitte Séroussi. Explainable Artificial Intelligence for Breast Cancer: A Visual Case-Based Reasoning Approach. Artificial Intelligence in Medicine, 94:42–53, March 2019.","Kuo-Sui Lin. A Case-Based Reasoning System for Interior Design Using a New Cosine Similarity Retrieval Algorithm. Journal of Information and Telecommunication, 4(1):91–104, January 2020.","Nahyun Kwon, Kwonsik Song, Moonseo Park, Youjin Jang, Inseok Yoon, and Yonghan Ahn. Preliminary Service Life Estimation Model for MEP Components Using Case-Based Reasoning and Genetic Algorithm. Sustainability, 11(11):3074, January 2019.","Rafael Freitas Reale, Walter da Costa Pinto Neto, and Joberto S. B. Martins. AllocTC-Sharing: A New Bandwidth Allocation Model for DS-TE Networks. In Proceedings of the VII Latin American Network Operations and Management Symposium, pages 1–4, Quito, Equador, October 2011.","Joberto Martins, Romildo Bezerra, Rafael Reale, and Gilvan Durães. Uma Visão Tutorial dos Modelos de Alocação de Banda como Mecanismo de Provisionamento de Recursos em Redes IP/MPLS. Revista de Sistemas e Computação, 5(2):144–155, December 2015.","Eliseu M. Oliveira, Rafael F. Reale, and Joberto S. B. Martins. Cognitive Management of Bandwidth Allocation Models with Case-Based Reasoning - Evidences Towards Dynamic BAM Reconfiguration. In Proceedings of the IEEE International Symposium on Computers and Communications (ISCC), pages 397–493, Brazil, June 2018.","Rafael Reale, Romildo Bezerra, and Joberto Martins. A Preliminary Evaluation of Bandwidth Allocation Model Dynamic Switching. International Journal of Computer Networks and Communications, 6(3):131–143, May 2014."]}

Context.The Metis coronagraph on board Solar Orbiter offers a new view of coronal mass ejections (CMEs), observing them for the first time with simultaneous images acquired with a broad-band filter in the visible-light interval and with a narrow-band filter around the H ILy-αline at 121.567 nm, the so-called Metis UV channel.Aims.We show the first Metis observations of a CME, obtained on 16 and 17 January 2021. The event was also observed by the EUI/FSI imager on board Solar Orbiter, as well as by other space-based coronagraphs, such as STEREO-A/COR2 and SOHO/LASCO/C2, whose images are combined here with Metis data.Methods.Different images are analysed here to reconstruct the 3D orientation of the expanding CME flux rope using the graduated cylindrical shell model. This also allows us to identify the possible location of the source region. Measurements of the CME kinematics allow us to quantify the expected Doppler dimming in the Ly-αchannel.Results.Observations show that most CME features seen in the visible-light images are also seen in the Ly-αimages, although some features in the latter channel appear more structured than their visible-light counterparts. We estimated the expansion velocity of this event to be below 140 km s−1. Hence, these observations can be understood by assuming that Doppler dimming effects do not strongly reduce the Ly-αemission from the CME. These velocities are comparable with or smaller than the radial velocities inferred from the same data in a similar coronal structure on the east side of the Sun.Conclusions.The first observations by Metis of a CME demonstrate the capability of the instrument to provide valuable and novel information on the structure and dynamics of these coronal events. Considering also its diagnostics capabilities regarding the conditions of the ambient corona, Metis promises to significantly advance our knowledge of such phenomena.

In this work, we present an investigation of the wind in the solar corona that has been initiated by observations of the resonantly scattered ultraviolet emission of the coronal plasma obtained with UVCS-SOHO, designed to measure the wind outflow speed by applying Doppler dimming diagnostics. Metis on Solar Orbiter complements the UVCS spectroscopic observations that were performed during solar activity cycle 23 by simultaneously imaging the polarized visible light and the H I Lyman-α corona in order to obtain high spatial and temporal resolution maps of the outward velocity of the continuously expanding solar atmosphere. The Metis observations, taken on May 15, 2020, provide the first H I Lyman-α images of the extended corona and the first instantaneous map of the speed of the coronal plasma outflows during the minimum of solar activity and allow us to identify the layer where the slow wind flow is observed. The polarized visible light (580–640 nm) and the ultraviolet H I Lyα (121.6 nm) coronal emissions, obtained with the two Metis channels, were combined in order to measure the dimming of the UV emission relative to a static corona. This effect is caused by the outward motion of the coronal plasma along the direction of incidence of the chromospheric photons on the coronal neutral hydrogen. The plasma outflow velocity was then derived as a function of the measured Doppler dimming. The static corona UV emission was simulated on the basis of the plasma electron density inferred from the polarized visible light. This study leads to the identification, in the velocity maps of the solar corona, of the high-density layer about ±10° wide, centered on the extension of a quiet equatorial streamer present at the east limb – the coronal origin of the heliospheric current sheet – where the slowest wind flows at about 160 ± 18 km s−1 from 4 R⊙ to 6 R⊙. Beyond the boundaries of the high-density layer, the wind velocity rapidly increases, marking the transition between slow and fast wind in the corona.

The communication network context in actual systems like 5G, cloud and IoT (Internet of Things), presents an ever-increasing number of users, applications and services that are highly distributed with distinct and heterogeneous communications requirements. Resource allocation in this context requires dynamic, efficient and customized solutions and Bandwidth Allocation Models (BAMs) are an alternative to support this new trend. This paper proposes the BAMSDN (Bandwidth Allocation Model through Software-Defined Networking) framework that dynamically allocates resources (bandwidth) for a MPLS (MultiProtocol Label Switching) network using a SDN (Software-Defined Networking)/OpenFlow strategy with BAM. The framework adopts an innovative implementation approach for BAM systems by controlling the MPLS network using SDN with OpenFlow. Experimental results suggest that using SDN/OpenFlow with BAM for bandwidth allocation does have effective advantages for MPLS networks requiring flexible resource sharing among applications and facilitates the migration path to a SDN/OpenFlow network., {"references":["E. Rachkidi, D. Belaïd, N. Agoulmine, and N. Chendeb, \"Cloud of Things Modeling for Efficient and Coordinated Resources Provisioning,\" in OTM Confederated Int. Conf. Springer, Sep. 2017, pp. 175–193.","L. Zuo, M. Zhu, and Q. Wu, \"Fast and Efficient Bandwidth Reservation Algorithms for Dynamic Network Provisioning,\" Journal of Network and Syst. Manag., vol. 23, no. 3, pp. 420–444, Jul. 2015.","B. Fan, S. Leng, and K. Yang, \"A Dynamic Bandwidth Allocation Algorithm in Mobile Networks with Big Data of Users and Networks,\" IEEE Network, vol. 30, no. 1, pp. 6–10, Jan. 2016.","J. Martins, R. Bezerra, G. Durães, and R. Reale, \"Uma Visão Tutorial dos Modelos de Alocação de Banda como Mecanismo de Provisionamento de Recursos em Redes IP/MPLS,\" Revista de Sistemas e Computação, vol. 5, no. 2, pp. 144–155, Dec. 2015.","R. Trivisonno, R. Guerzoni, I. Vaishnavi, and A. Frimpong, \"Network Resource Management and QoS in SDN-Enabled 5g Systems,\" in IEEE GLOBECOM 2015. IEEE, Dec. 2015, pp. 1–7.","M. Pitek, M. Medvecký, and S. Kluik, \"A-MAR: A New Bandwidth Constraint Model for DS-TE Networks,\" in 38th Int. Conf. on Telecommunications and Signal Processing, Jul. 2015, pp. 1–5.","T. Onali and L. Atzori, \"Traffic Engineering in Next Generation Networks Using Genetic Algorithms,\" in GLOBECOM, Nov. 2008, pp. 1–5.","D. Kreutz, F. Ramos, P. Verissimo, C. Rothenberg, S. Azodolmolky, and S. Uhlig, \"Software-Defined Networking: A Comprehensive Survey,\" Proc. of IEEE, vol. 103, no. 1, pp. 14–76, Dec. 2014.","F. L. Faucher and W. Lai, \"Maximum Allocation Bandwidth Constraints Model for DSTE,\" Tech. Rep. RFC 4125, Jun. 2005.","W. Neto, S. Brito, and J. Martins, \"Algoritmos de Seleção de Caminho e Gerenciamento de Banda Compartilhada conforme ao Modelo RDM para Classes de Tráfego em Rede DS-TE,\" in SBRC 2008, Rio de Janeiro, May 2008, pp. 537–552.","R. F. Reale, W. d. C. P. Neto, and J. S. B. Martins, \"AllocTC-sharing: A New Bandwidth Allocation Model for DS-TE Networks,\" in LANOMS 2011. Equador: IEEE, Oct. 2011, pp. 1–4.","J. Martins, R. Reale, and R. Bezerra, \"G-BAM: A Generalized Bandwidth Allocation Model for IP/MPLS/DS-TE Networks,\" Int. Journal of Computer Information Systems and Industrial Management Applic., vol. 6, pp. 635–643, Dec. 2014.","R. Reale, R. Bezerra, and J. Martins, \"A Preliminary Evaluation of Bandwidth Allocation Model Dynamic Switching,\" Int. Journal of Computer Networks & Comm., vol. 6, no. 3, pp. 131–143, May 2014.","X. Hesselbach, J. Amazonas, and J. Botero, \"Management of resources under priorities in EON using a modified RDM based on the squattingkicking approach,\" in 18th Int. Conf. on Transparent Optical Networks, 2016, pp. 1–5.","R. Reale, R. Bezerra, G. Durães, A. Soares, and J. Martins, \"Evaluating the Applicability of Bandwidth Allocation Models for EON Slot Allocation,\" in IEEEANTS 2017, Dec. 2017, pp. 1–6.","J. B. Goldberg, S. Dasgupta, and J. C. d. Oliveira, \"Bandwidth Constraint Models: A Performance Study with Preemption on Link Failures,\" in IEEE Globecom 2006, Nov. 2006, pp. 1–5.","T. Shan and O. W. W. Yang, \"Bandwidth Preemption Algorithms for Differentiated Service aware Traffic Engineering,\" in GLOBECOM 2005, vol. 1, Nov. 2005, pp. 535–539.","S. Jain, A. Kumar, S. Mandal, J. Ong, L. Poutievski, A. Singh, S. Venkata, J. Wanderer, J. Zhou, M. Zhu, J. Zolla, U. Hölzle, S. Stuart, and A. Vahdat, \"B4: Experience with a Globally-deployed Software Defined Wan,\" in ACM SIGCOMM 2013, USA, 2013, pp. 3–14.","M. Tanha, D. Sajjadi, R. Ruby, and J. Pan, \"Traffic Engineering Enhancement by Progressive Migration to SDN,\" IEEE Communications Letters, vol. 22, no. 3, pp. 438–441, Mar. 2018."]}

Network neutrality (NN) is a principle of equal treatment of data in network infrastructures with fairness and universality being the primary outcomes of the NN management practice. For networks, the accomplishment of NN management practice is essential to deal with heterogeneous user requirements and the ever-increasing data traffic. Current tools and methods address the NN problem by detecting network neutrality violations and detecting traffic differentiation. This paper proposes the NN-PCM (Network Neutrality Policy Conformance Module) that deploys the BEREC network neutrality policy using a bandwidth allocation model (BAM). The NN-PCM new approach allocates bandwidth to network users and accomplishes the BEREC NN policy concomitantly. Network neutrality is achieved by grouping users with similar traffic requirements in classes and leveraging the bandwidth allocation model's characteristics. The conceptual analysis and simulation results indicate that NN-PCM allocates bandwidth to users and accomplishes BEREC network neutrality conformance \emph{by design} with transparent, non-discriminatory, exceptional, and proportional management practices., {"references":["Stocker V, Smaragdakis G, Lehr W. The State of Network Neutrality Regulation. ACM SIGCOMM Computer Communication Review 2020; 50(1): 45–59.","Schewick Bv. Network Neutrality and Quality of Service: What a Non-Discrimination Rule Should Look Like. Stanford Law Review 2015; 67(1): 1–129.","Wu T. Network Neutrality, Broadband Discrimination. Journal of Telecom. and High Technology Law 2005; 2: 141–180.","Maille P, Simon G, Tuffin B. Toward a Net Neutrality Debate That Conforms to the 2010s. IEEE Communications Magazine 2016; 54(3): 94–99.","Valletti T, Peitz M, Greenstein S. Net Neutrality: A Fast Lane to Understanding the Trade-offs.Working Paper 16- 01, University of Mannheim; : 2016.","Webb M. Net Neutrality: A Regulatory Perspective. In: ITU; 2012; Sri Lanka.","BEREC . Guidelines on the Implementation by National Regulators of European Net Neutrality Rules.; 2016. BoR (16) 127.","Commission FC. Protecting and Promoting the Open Internet. Tech. Rep. 15-24, ; Washington: 2015.","Brazil CD. Decreto No 8.771.; 2016.","Belli L, Bergen vM. A Discourse-Principle Approach to Network Neutrality: A Model Framework and its Application. tech. rep., ; : 2013.","Marsden C. Comparative Case Studies in Implementing Net Neutrality: A Critical Analysis of Zero Rating. SCRIPTed 2016; 13(1): 1–39.","Garrett T, Setenareski LE, Peres LM, Bona LCE, Duarte EP. Monitoring Network Neutrality: A Survey on Traffic Differentiation Detection. IEEE Communications Surveys Tutorials 2018: 1–1.","Bourreau M, Kourandi F, Valletti T. Net Neutrality with Competing Internet Platforms. The Journal of Industrial Electronics 2015; 63(1): 30–73.","Peitz M, Schuett F. Net Neutrality and Inflation of Traffic. Int. Journal of Industrial Organization 2016; 46: 16–62.","Li F, Niaki AA, Choffnes D, Gill P, Mislove A. A Large- Scale Analysis of Deployed Traffic Differentiation Practices. In: Proceedings of the ACM Special Interest Group on Data Communication - SIGCOMM. ; 2019; Beijing, China: 130–144.","Wójcik R. Net Neutral Quality of Service Differentiation in Flow-Aware Networks. PhD thesis. AGH University of Science and Technology, Kraków, Poland; 2011.","Ravaioli R, Urvoy-Keller G, Barakat C. Towards a General Solution for Detecting Traffic Differentiation at the Internet Access. In: Proceedings of the 27th International Teletraffic Congress (ITC). ; 2015: 1–9","Zhang Z, Mara O, Argyraki K. Network Neutrality Inference. In: SIGCOMM '14. Association for Computing Machinery; 2014; Chicago, Illinois, USA: 63–74.","Maltinsky A, Giladi R, Shavitt Y. On Network Neutrality Measurements. ACM Transactions on Intelligent Systems and Technology 2017; 8(4): 56:1–56:22.","MayerW, Schreiber T,Weippl E. A Framework for Monitoring Net Neutrality. In: Proceedings of the 13th International Conference on Availability, Reliability and Security (ARES); 2018; Hamburg, Germany: 1–10.","SivaramanV, Madanapalli SC,Kumar H, Gharakheili HH. OpenTD: Open Traffic Differentiation in a Post-Neutral World. In: SOSR '19. Association for Computing Machinery; 2019; San Jose, CA, USA: 119–126.","Stocker V, Smaragdakis G, LehrW. The State of Network Neutrality Regulation.; 2020.","Bauer JM, Knieps G. Complementary Innovation and Network Neutrality. Telecommunications Policy 2018; 42(2): 172 – 183.","Glass V, Tardiff T. A New Direction for the Net Neutrality Debate. Telecommunications Policy 2019; 43(3): 199 – 212.","Abiteboul S, Stoyanovich J. Transparency, Fairness, Data Protection, Neutrality: Data Management Challenges in the Face of New Regulation.; 2019.","Ma RT, Misra V. Routing Money, Not Packets: A Tutorial on Internet Economics. In: SIGMETRICS '17 Abstracts. Association for Computing Machinery; 2017; Urbana- Champaign, Illinois, USA: 69–70.","Choi JP, Jeon DS, Kim BC. Net Neutrality, Business Models, and Internet Interconnection. American Economic Journal: Microeconomics 2015; 7(3): 104–141.","Reale R, Bezerra R, Martins J. G-BAM: A Generalized Bandwidth Allocation Model for IP/MPLS/DS-TE Networks. International Journal of Computer Information Systems and Industrial Management Applications 2014; 6: 635–643. doi: 10.5281/zenodo.1292771","Reale RF. Orquestração Cognitiva e Dinâmica da Alocação de Recursos para Redes MPLS/DSTE. PhD thesis. Salvador University - UNIFACS, Salvador, Brazil; 2019.","Faucher FL, Lai W. Maximum Allocation Bandwidth Constraints Model for DiffServ-aware MPLS Traffic Engineering. Request for Comments RFC 4125, IETF; : 2005.","Le Faucheur F, Boyle J, Kompella K, Townsend W, Nadeau TD, Skalecki D. Russian Dolls Bandwidth Constraints Model for Diffserv-aware MPLS Traffic Engineering. Request for Comments - RFC RFC 4127, Internet Engineering Task Force - IETF; : 2005.","Tata C, Kadoch M. CAM: Courteous bandwidth constraints allocation model. In: Proceedings of the 20th International Conference on Telecommunications - ICT; 2013: 1–5","Neto WCP, Martins JSB. Adapt-RDM - A Bandwidth Management Algorithm suitable for DiffServ Services Aware Traffic Engineering. In: IEEE/IFIP Network Operations and Management Symposium; 2008: 975–978.","Reale RF, Neto WCP, Martins JSB. AllocTC-Sharing: A New Bandwidth Allocation Model for DS-TE Networks. In: Proceedings of the VII Latin American Network Operations and Management Symposium; 2011; Quito, Equador: 1–4","Bahnasse A, Louhab FE, Oulahyane HA, Talea M, Bakali A. Smart Bandwidth Allocation for Next Generation Networks Adopting Software-Defined Network Approach. Data in Brief 2018; 20: 840–845. doi: 10.1016/j.dib.2018.08.091","Oliveira EM, Reale RF, Martins JSB. Cognitive Management of Bandwidth Allocation Models with Case-Based Reasoning - Evidences Towards Dynamic BAMReconfiguration. In: Proceedings of the IEEE International Symposium on Computers and Communications (ISCC); 2018; Natal, Brazil: 1–7","Sadon SK, Din NM, Al-Mansoori MH, et al. Dynamic Hierarchical Bandwidth Allocation Using Russian Doll Model in Epon. Computers & Electrical Engineering 2012; 38(6): 1480–1489. doi: 10.1016/j.compeleceng.2012.05.002","Trivisonno R, Guerzoni R, Vaishnavi I, Frimpong A. Network Resource Management and QoS in SDN-Enabled 5G Systems. In: Proceedings of the IEEE Globecom; 2015: 1–7.","Durães G, Reale R, Bezerra R, Fontinele A, Soares A, Martins JSB. Evaluating the Applicability of Bandwidth Allocation Models for EON Slot Allocation. In: Proceedings of the IEEE International Conference on Advanced Networks and Telecommunications Systems (IEEEANTS); 2017; Bhubaneswar, Odisha, India: 1–6.","Hesselbach X, Dantas J, Amazonas JR, Botero JF, Piney JR. Management of Resources under Priorities in EON Using a Modified RDM Based on the Squatting-Kicking Approach. In: IEEE; 2016; Trento, Italy: 1–5","Reale RF, Bezerra RM, Martins JSB. Analysis of Bandwidth Allocation Models Reconfiguration Impacts. In: Proceedings of the III International Workshop on ICT Infrastructures and Services (ADVANCE); 2014; Florida, US: 67–76","BEREC . All You Need to Know about Net Neutrality Rules in the EU.; 2020.","Belli L. Net Neutrality Reloaded: Zero Rating, Specialised Service, Ad Blocking and Traffic Management. Fundação Getulio Vargas - Direito . 2016.","Belli L, De Filippi P. The Value of Network Neutrality for the Internet of Tomorrow. tech. rep., CERSA - Centre d'Etudes et de Recherches de Sciences Administratives et Politiques; : 2013.","Barreto D, Reale R, Martins J. Neutralidade de Rede com Modelos de Alocação de Banda e Comportamentos G-BAM Análise de Compatibilidade. In: Proceedings of the XXXV Computer Networks and Distributed Systems Brazilian Symposium (SBRC); 2017; Belém, Brazil: 702–715.","Kreutz D, Ramos FMV, Verissimo P, Rothenberg CE, Azodolmolky S, Uhlig S. Software-Defined Networking: A Comprehensive Survey. Proceedings of the IEEE 2014; 103(1): 14–76.","Mendiola A, Astorga J, Jacob E, Higuero M. A Survey on the Contributions of Software-Defined Networking to Traffic Engineering. IEEE Communications Surveys Tutorials 2017; 19(2): 918–953.","ITU-T . Y.1541: Network Performance Objectives for IPBased Services.; 2002.","ITU-T . Y.1221: Traffic Control and Congestion Control in IP-Based Networks.; 2002."]}

Summary Bandwidth Allocation Models (BAMs) are resource allocation methods used for networks in general. BAMs are currently applied for handling resources such as bandwidth allocation in MPLS DS-TE networks (LSP setup). In general, BAMs define resource restrictions by ‘class’ and allocate the available resources on demand. This is frequently necessary to manage large and complex systems like routing networks. G-BAM is a new generalized BAM that, by configuration, incorporates the ‘behavior’ of existing BAMs (MAM, RDM, G-RDM and AllocTC-Sharing). In effect, any current available BAM ‘behavior’ is reproduced by G-BAM by simply adjusting its configuration parameters. This paper focuses on investigating the applicability of using autonomy together with BAMs for improve performance and facilitating the management of MPLS DS-TE networks. It is investigated the applicability of ‘BAM switching’ using a framework with autonomic characteristics. In brief, it is investigated the switching among ‘BAM behaviors’ and BAM's reconfiguration with distinct network traffic scenarios by using G-BAM. Simulation results suggest that the autonomic switching of ‘BAM behaviors’ based on high-level management rules (Service Level Agreements, Quality of Service (QoS) or other police) may result in improving overall network management and operational parameters such as link utilization and preemption. Copyright © 2016 John Wiley & Sons, Ltd.

The opportunities and critical aspects related to the use of low heating value gaseous fuels produced from biomasses in an integrated energy system composed by a micro gas turbine, an ORC as bottom system and a gasification system are analyzed in the paper. The aim is to individuate an efficient strategy to an energetic re-use of organic solid waste with small plants in a distributed energy point of view. The study was carried out through thermodynamic analysis of each component. Results of simulations highlight the possibility of using syngas in commercial MGTs with waste heat recovery when mixed with methane but specially biogas to obtain a full renewable power generation.

Management is a complex task in today’s heterogeneous and large scale networks like Cloud, Internet of Things (IoT) , vehicular and Multiprotocol Label Switching (MPLS) networks. Likewise, researchers and developers envision the use of artificial intelligence techniques to create cognitive and autonomic management tools that aim better assist and enhance the management process cycle. Bandwidth Allocation Models (BAMs) are a resource allocation solution for networks that need to share and optimize limited resources like bandwidth, fiber or optical slots in a flexible and dynamic way. This paper proposes and evaluates the use of Case-based Reasoning (CBR) for the cognitive management of BAM reconfiguration in MPLS networks. The results suggest that CBR learns about bandwidth request profiles associated with the current network state and is able to dynamically define or assist in BAM reconfiguration. The BAM reconfiguration approach adopted is based on switching among available BAM implementations (Maximum Allocation Model, Russian Dolls Model and AllocTC-Sharing). The cognitive management proposed allows BAMs self-configuration and results in optimizing the utilization of network resources., {"references":["H. Elsawy, H. Dahrouj, T. Y. Al-naffouri, and M. s. Alouini, \"Virtualized cognitive network architecture for 5g cellular networks,\" IEEE Communications Magazine, vol. 53, no. 7, pp. 78–85, Jul. 2015.","Q. H. Mahmoud, Cognitive Networks Towards Self-Aware Networks. Hoboken, NJ: John Wiley & Sons, 2007, oCLC: 839295888.","O. Rendon, F. Estrada-Solano, R. Boutaba, N. Shahriar, M. Salahuddin, N. Liman, and S. Ayoubi, \"Machine Learning for Cognitive Network Management,\" IEEE Communications Magazine, pp. 1–9, 2018.","L. Song, D. Niyato, Z. Han, and E. Hossain, \"Game-theoretic resource allocation methods for device-to-device communication,\" IEEE Wireless Communications, vol. 21, no. 3, pp. 136–144, Jun. 2014.","S. Singh and I. Chana, \"QoS-Aware Autonomic Resource Management in Cloud Computing: A Systematic Review,\" ACM Comput. Surv., vol. 48, no. 3, pp. 42:1–42:46, Dec. 2015.","R. Reale, R. Bezerra, and J. Martins, \"A Preliminary Evaluation of Bandwidth Allocation Model Dynamic Switching,\" Int. Jour. of Computer Networks & Communications, vol. 6, no. 3, pp. 131–143, May 2014","J. Hui, \"Resource Allocation for Broadband Networks,\" IEEE Jour. on Selec. Areas in Commun., vol. 6, no. 9, pp. 1598–1608, Dec. 1988.","L. Xiao, M. Johansson, and S. P. Boyd, \"Simultaneous Routing and Resource Allocation Via Dual Decomposition,\" IEEE Transactions on Communications, vol. 52, no. 7, pp. 1136–1144, Jul. 2004.","M. Guizani, B. Khalfi, M. B. Ghorbel, and B. 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LNCS. Springer, Berlin, Heidelberg, Sep. 2006, pp. 121–135.","P. R. CohN. Agoulmine, Ed., Autonomic Network Management Principles: From Concepts to Applications. Amsterdam: Elsevier, 2011.en and A. E. Howe, \"Toward AI Research Methodology: Three Case Studies in Evaluation,\" IEEE Transactions on Systems, Man, and Cybernetics, vol. 19, no. 3, pp. 634–646, May 1989.","B. Jennings, S. V. D. Meer, S. Balasubramaniam, and D. Botvich, \"Towards Autonomic Management of Communications Networks,\" IEEE Communications Magazine, vol. 45, no. 10, pp. 112–121, Oct. 2007.","A. Aamodt and E. Plaza, \"Case-Based Reasoning: Foundational Issues, Methodological Variations, and System Approaches,\" Artificial Intelligence Communications, vol. 7, no. 1, pp. 39–59, 1994.","E. Oliveira, R. Reale, and J. Martins, \"Evaluating CBR Similarity Functions for BAM Switching in Networks with Dynamic Traffic Profile,\" in 5th Int. Workshop on ADVANCEs in ICT Infrastructure and Services, Paris, Jan. 2017, pp. 1–7.","J. A. Recio-Garc´ıa, P. A. Gonz´alez-Calero, and B. D´ıaz-Agudo, \"J Colibri2: A Framework for Building Case-Based Reasoning Systems,\" Science of Computer Programming, vol. 79, pp. 126–145, Jan. 2014."]}

The paper reports the experimental results concerning emissions from 30 kWe commercial micro gas turbine feed with blends of straight vegetable oil with fossil fuel. Both gaseous and particulate emissions were measured at full and partial load for blends 10% v/v and 20% v/v of rapeseed and sunflower oils with JET A1 kerosene. The variations of nitric oxide and carbon monoxide emissions were taken into account to evaluate the combustor behavior at different loads and blends. The effects of the fuel composition on the variations, in terms of concentrations and dimensions, of ultrafine – particulate matter were also evaluated. NOx and CO emissions are practically insensitive to the composition of the fuel being the differences within the experimental uncertainty of the instrumentation. This demonstrates a similar overall combustion at both partial and full load for the five fuels used (Jet A1 and four SVO blends). On the contrary, particle matter emission is three times for blends of rapeseed oil and more than fifty times greater for blends of sunflower oil with respect to pure Jet A1. The differences are ascribed to the chemical structure of the vegetable oil tested.

Bandwidth Allocation Models (BAMs) are used in order to define Bandwidth Constraints (BCs) in a perclass basis for MPLS/DS-TE networks and effectively define how network resources like bandwidth are obtained and shared by applications. The BAMs proposed (MAM – Maximum Allocation Model, RDM – Russian Dolls Model, G-RDM – Generic RDM and AllocTC-Sharing) attempt to optimize the use of bandwidth resources on a per-link basis with different allocation and resource sharing characteristics. As such, the adoption of distinct BAMs and/or changes in network resource demands (network traffic profile) may result in different network traffic allocation and operational behavior for distinct BAMs. This paper evaluates the resulting network characteristics (link utilization, preemption and flows blocking) of using BAMs dynamically with different traffic scenarios. In brief, it is investigated the dynamics of BAM switching with distinct traffic scenarios. The paper presents initially the investigated BAMs in relation to their behavior and resource allocation characteristics. Then, distinct BAMs are compared using different traffic scenarios in order to investigate the impact of a dynamic change of the BAM configured in the network. Finally, the paper shows that the adoption of a dynamic BAM allocation strategy may result in benefits for network operation in terms of link utilization, preemption and flows blocking.

The Bandwidth Allocation Models (MAM, RDM, G-RDM and AllocTC-Sharing) are management alternatives currently available which propose different resource (bandwidth) allocation strategies in multiservice networks. The BAM adoption by a network is typically a management choice and configuration task executed by the network operations and management system setup in a static or nearly static way. This paper proposes and explores the alternative of allowing BAM definition and configuration on a more dynamic way. In effect, one of the basic motivations towards BAM dynamic allocation is the fact that multiservice networks characteristics (traffic load) may change considerably in daily network operation and, as such, some dynamics in BAM allocation should be introduced in order to improve performance. A framework is presented supporting BAM dynamic allocation. The framework adopts an OpenFlow-based software-defined networking (SDN) implementation approach in order to support scalability issues with a centralized controller and management network view. The framework architecture also supports the implementation of some autonomic characteristics which, in brief, look for improving and facilitating the decision-making process involved with BAM provisioning in a multiservice network. A proof of concept is presented evaluating different BAM performance under different traffic loads in order to demonstrate the framework strategy adopted.

Relazione Tecnica sulle Attività "Abbattimento di NOx" svolte nell'ambito del SP "Emissioni " del progetto TRIM - Tecnologia e Ricerca Industriale per la Mobilità Marina, periodo 1.7.2017 - 31.12.2017

In order to test the hypothesis that a greater sympathetic activity underlies partial reversibility of the bronchial obstruction in selected patients with chronic obstructive pulmonary disease (COPD), we assessed the pulmonary clearance of inhaled 123 I-meta-iodobenzylguanidine ( 123 I-MIBG) radioaerosol in 10 patients with fixed and nine with reversible obstruction. The clearance of inhaled 123 I-MIBG is known to be inversely related to 123 I-MIBG uptake by adrenergic terminals. Groups were matched for age and judged free from confounding comorbidity. The penetration index did not distinguish between the groups (fixed obstruction, 97.39 ± 14.59%; reversible obstruction, 89.09 ± 19.95%; P= 0.659); this excludes the possibility that the inequality of tracer penetration could affect 123 I-MIBG clearance. The 123 I-MIBG clearance was 140.92 ± 7.67 min in patients with fixed obstruction and 151.08±31.54 min in patients with reversible obstruction (P=0.604). In conclusion, COPD patients with fixed and reversible obstruction show comparable binding of the tracer to adrenergic pulmonary receptors. Thus, a greater receptor responsiveness or post-receptor mechanism probably underlies the partial reversibility of bronchial obstruction.

Introduction - Primary intraventricular haemorrhage (PIVH) is an uncommon type of intracerebral haemorrhage. Relatively little is known about clinical and imaging features, and even less about prognosis and predictors of mortality. Material and methods - We analysed clinical and imaging features, causative factors and outcome of 26 patients with CT brain scan evidence of PIVH. A multivariate regression model of failure time data was used to assess predictors of in-hospital mortality. Results - Loss of consciousness was the first manifestation of PIVH in six patients and occurred after all other symptoms in five. In other patients, onset was characterized by headache, vomiting, confusion and disorientation (n = 8) or by headache with or without vomiting (n = 7). Angiography revealed vascular malformations in eight patients (31%). Other possible causative factors were clotting disorder in one patient and arterial hypertension in 10. No cause was identified in seven patients. Early hydrocephalus was the most frequent complication and resolved spontaneously in a minority of patients. In-hospital mortality was high (42%): four patients died early of direct consequence of bleeding and seven died after clinical worsening because of increasing hydrocephalus or other adverse events. Multivariate analysis indicated Glasgow Coma Scale ≤ 8 (OR 4.67; 95% CI 1.22-17.92) and early hydrocephalus (OR 4.93; 95% CI 1.13-21.59) as independent predictors of in-hospital mortality. Conclusion - In patients with PIVH, hydrocephalus seems to be a critical determinant of in-hospital mortality and this suggests the need for early treatment strategies.

Introduction : Surgical release is the most effective therapy for the symptoms of carpal tunnel syndrome (CTS). It is widely considered that surgery may be ineffective in ‘extreme' cases (those with atrophy of the thenar eminence muscles and no sensory and motor response of the median nerve). Objective : To report clinical and eletrophysiological outcome of 10 subjects with ‘extreme' CTS surgically treated. Methods : Ten hands belonging to 10 patients (9 women and one man, mean age 65 years) underwent surgical release by the mini-incision of the palm technique. All showed atrophy of thenar eminence and absence of motor and sensory responses of the median nerve. The protocol consisted of clinical and electrophysiological evaluation, with the patient completing the self-administered Boston questionnaire (BQ) before the operation and one and 6 months after it. Results : After surgical release, all patients reported an absence of pain and disappearance or reduction of paraesthesia. Six months after the operation, motor and sensory responses of the median nerve returned in 8 and 5 hands, respectively. The BQ showed a significant improvement in symptom and functional scores, although muscle atrophy remained unchanged. No correlation was found between the degree of clinical and electrical improvement and the age of the patients. Conclusion : It is possible to obtain good clinical and electrophysiological results even in extreme cases of CTS.

A prospective study of electrophysiological examination and the Boston self-administered questionnaire (BQ) was carried out in patients with surgically-treated carpal tunnel syndrome. There were 104 hands in 93 patients (13 men and 80 women, mean age 56 years). The BQ was used to assess the severity of symptoms and function, and nerve conduction studies were done before surgical release by short incision at the palm, and at follow-ups 1 and 6 months after surgery. The BQ severity score improved or became normal in 98% of hands. The mean BQ scores and distal sensory and motor conduction velocities in the median nerve showed significant improvement at the 1 month follow-up. Further significant improvement was found at 6 months. There was no relationship between the improvements in BQ scores and the distal conduction in the median nerve. The degree of improvement in sensory and motor distal conduction velocities could be forecast from presurgical values, whereas the degree of improvement in the symptoms and the functional status after release could not be predicted from the presurgical BQ scores.

The Bandwidth Allocation Models (BAMs) are management possibilities to bandwidth allocation in multiservice networks. This paper evaluates and explores the alternative of allowing BAM definition and configuration on a more dynamic way. In effect, one of the basic motivations towards BAM dynamic allocation is the fact that multiservice networks characteristics (traffic load) may change considerably in daily network operation and, as such, some dynamics in BAM allocation should be introduced in order to improve network overall performance. A proof of concept is presented evaluating different BAM performance under different traffic loads in order to demonstrate the need to dynamically manage BAM configuration by management systems in general.

This paper considers the problem of locating closely-spaced coherent emitters. Classical TDOA-based emitter location methods assume only a single emitter is being estimated. As a result, when multiple emitters that cannot be resolved during detection exist, the MSE performance is significantly degraded. These errors are due to the fact that the TDOA observation model does not account for multiple transmissions. We propose a new TDOA observation model that can resolve multiple emitted signals. We show a significant improvement in MSE when locating multiple emitters using our new model as compared with the classical one-emitter assumption TDOA model.

In this paper we introduce a new diagnostic technique that uses prominence EUV and UV absorption to determine the prominence plasma electron temperature and column emission measure, as well as He/H relative abundance; if a realistic assumption on the geometry of the absorbing plasma can be made, this technique can also yield the absorbing plasma electron density. This technique capitalizes on the absorption properties of Hydrogen and Helium at different wavelength ranges and temperature regimes. Several cases where this technique can be successfully applied are described. This technique works best when prominence plasmas are hotter than 15,000 K and thus it is ideally suited for rapidly heating erupting prominences observed during the initial phases of coronal mass ejections. An example is made using simulated intensities of 4 channels of the SDO/AIA instrument. This technique can be easily applied to existing observations from almost all space missions devoted to the study of the solar atmosphere, which we list.

DiffServ-aware MPLS-TE (DS-TE) allows bandwidth reservation for Traffic Classes (TCs) in MPLS-based engineered networks and, as such, improves the basic MPLS-TE model. In DS-TE networks, per-Class quality of service guarantees are provided while being possible to achieve improved network utilization. DS-TE requires the use of a Bandwidth Allocation Model (BAM) that establishes the amount of bandwidth per-Class and any eventual sharing among them. This paper proposes a new bandwidth allocation model (AllocTC-Sharing) in which the higher priority traffic classes are allowed to use non allocated resources of lower priority traffic classes and vice versa. By adopting this dual sense allocation strategy for dynamic bandwidth allocation, it is shown that AllocTC-Sharing model preserves bandwidth constraints for traffic classes and improves overall link utilization., Comment: 7th Latin American Network Operations and Management Symposium, LANOMS 2011

In a previous publication, the so-called statistical population analysis (SPA) has been developed and applied to 1D periodic systems (polymers). The goal of the present work is to implement the formalism extended to higher dimensional cases and to perform its application to 2D layers (graphite and hexagonal boron nitride), 3D crystals (diamond and cubic boron nitride) and two cases of atomic adsorption on surface (carbon+graphite; oxygen+graphite), in the framework of the semiempirical MNDO-CO-LCAO state function approach. Rather than attempting to improve the band structures our goal is to give complete detail of the electronic distribution in atoms and bonds by means of population analysis algorithms for the above-mentioned systems. SPA results permit the showing of striking and novel effects on chemical bonding arising from the cooperative contribution of the whole crystalline environment. Different kinds of effective chemisorption bonds are detected for the absorption cases on a surface which is characterized by binding energies of opposite signs. The partitioning scheme of SPA shows that the proposed population analysis is a suitable tool for describing the electronic distribution of isolated and interacting crystalline systems even encouraging its application to the study of more complex situations in which catalysis phenomena are present.

After some years of basic studies and design, a prototype of a multi-cavity external flow air (or volumetric) receiver was tested at the Plataforma Solar de Almeria test facility. The absorber consists of a pack of SiSiC 9.0 × 4.8 mm (net) channels with a length of 150 mm with vertical and horizontal walls 5.0 and 1.6 mm thick, respectively. Experiments lasted for 30 days in the summer of 1990 and outlet air temperatures, power transferred to air, and efficiency were recorded as functions of solar incident flux and air flowrate. A good accordance between measured and predicted results was noticed, within the limits of accuracy of the data acquisition system of the facility and of the experimental system. Due to its compactness and despite its low mass, the structural behavior of the receiver was also satisfactory; the most important result was to confirm the validity of the concept and of the physical analysis on which the design is based.

We present preliminary results from the analysis of a long duration flare that was observed in a serendipitous XMM-Newton detection of the M star CD-39 7717 B (TWA 11 B), member of the young stellar association TW Hya. Only the rise phase (with a duration of ~35 ks) and possibly the flare peak are present in the light-curve. The decay phase was not monitored. The fluorescent iron emission line at 6.4 keV was observed during this event. As far as we are concerned, since TWA 11 B seems to have no disk, this is only the third detection of Fe photospheric fluorescence. During the flare, the X-ray flux increased a factor of ~4. Taking the light curve and the evolution of the hardness ratio into account, we interpret the rise phase as resulting from the ignition of a first group of loops (part 1) which triggered a subsequent two-ribbon flare (part 2). Part 1 is analysed using the Reale's (2007) model, since it has been assumed to be dominated by a single loop. For part 2, the diagnostic method for two-ribbon flares developed by Kopp & Poletto (1984) is applied. Loop semi-lengths of about 2.5-3.0 stellar radii are obtained. These large structures were previously detected only in very young objects, this is the first time that are detected in a more evolved (~8 Myr) star.

The solar corona is a template to study and understand stellar activity. However the solar corona differs from that of active stars: the Sun has lower X‐ray luminosity, and on average cooler plasma temperatures. Active stellar coronae have a hot peak in their emission measure distribution, EM (T), at 8–20 MK, while the non‐flaring solar corona has a peak at 1–2 MK. In the solar corona significant amounts of plasma at temperature ∼10 MK are observed only during flares.To investigate what is the time‐averaged effect of solar flares we measure the disk‐integrated time‐averaged emission measure, EMF (T), of an unbiased sample of solar flares. To this aim we analyze uninterrupted GOES/XRS light curves over time intervals of one month. We also obtain the EMQ (T) of the quiescent corona for the same time intervals from Yohkoh/SXT data. To investigate variations due to the solar cycle we evaluate EMF (T) and EMQ (T) at different phases of the cycle between December 1991 and April 1998.Irrespective of the solar cycle phase, EMF (T) appears as a peak in the distribution, and it is significantly larger than the values of EMQ (T) for T∼5–10 MK. Adding EMF (T) and EMQ (T) we obtain for the first time a time average EM (T) of the entire solar corona: it is double‐peaked, with the hot peak, due to time‐averaged flares, being located at temperatures similar to those of active stars, but less enhanced.In the assumption that the heating of the corona is entirely due to flares, from nano‐ to macro‐flares, a two peak EM (T) distribution suggests that then either the flare distribution or the confined plasma response to flares, or both, are bimodal. Moreover the EMF (T) shape supports the hypothesis that the hot EM (T) peak of active coronae is due to unresolved solar‐like flares. If this is the case, quiescent and flare components should follow different scaling laws for increasing stellar activity.

High spectral resolution X-ray observations of classical T Tauri stars (CTTSs) demonstrate the presence of plasma at T~2-3×10^6 K and ne~10^11-10^13 cm-3. Stationary models suggest that this emission is due to shock-heated accreting material. We address this issue by a 1-D hydrodynamic model of the impact of the accretion flow onto a chromosphere of a CTTS with the aim of investigating the stability of accretion shock and the role of the chromosphere. Our simulations include the effects of gravity, radiative losses from optically thin plasma, the thermal conduction and a detailed modeling of the stellar chromosphere. Here we present the results of a simulation based on the parameters of the CTTS MP Mus.

The statistical population analysis for the spin distribution of molecular systems is developed in a similar way to that of particle population in molecules and crystalline solid state systems. The formalism of the number of particles obtained by means of the quantum statistical theory is applied to this distribution and the corresponding statistical unpaired number of particles arises. Then a partition for that population is proposed. It is shown that this method is valid for any kind of wavefunction. Information theory is used in order to interpret the proportionality relation between the statistical number of unpaired spin particles and the corresponding causal one. Also, the connection with Mulliken's type of analysis of spin distributions is discussed. Numerical examples are presented for UHF (or DODS) wavefunctions in the AM1 semiempirical approach. Some of these examples help to justify using semiempirical methods for describing spin distributions in molecular systems because of their agreement with experimental data.

The concept of a multi-cavity volumetric solar receiver is very attractive for the profitability of certain of its characteristics such as high efficiency and economy. The absorber is based on a pack of small ceramic cavities which intercept and absorb the inherent high solar flux reflected from an array of mirrors. Atmospheric air acts as a coolant medium when it is drawn through the pack. A model for an overall heat transfer performance of the receiver is given and numerically solved.

An experimental loop has been set up to demonstrate the technical feasibility of a hot water aquifer store and to validate an original physical model and code as well as the engineering based on it. The model applies to a “reference aquifer” and an appropriate exploitation system, as defined in the text. Experiments have been carried out for a period of 37 days, 15 days for injection of hot water at 40°C, 7 days of storage at rest, 15 days for pumping out stored hot water. The system has worked perfectly at the specified performance. Measured temperatures show a very good accordance with temperatures predicted by the numerical model. The rated 52% efficiency has been confirmed. Although more extended experiments shall be performed, one can conclude that the engineering of the system is appropriate and the physical model and numerical code developed by the authors are satisfactory.

Theoretical expressions for spin populations are presented. The expressions were derived from the statistical concept of the number of particles for an extended system (molecule or crystal). Numerical results are shown over a set of selected molecular systems and some theoretical conclusions are discussed.

An improvement of the energy efficiency ratio of air conditioning systems results when water-to-water dual-mode units are coupled to an aquifer of suitable characteristics which functions as a seasonal thermal storage. The evaluation of the system efficiency from a thermodynamic study is needed, to assess the interactions between the units and the aquifer. A comprehensive thermodynamic analysis is carried out in this paper. A procedure for a numerical evaluation of the system performance and optimization is presented in a convenient form for development and application of the system. A simplified method is also given for preliminary design purposes.

BACKGROUND Two cases of neuroma of the sural nerve after stripping of the small saphenous vein are reported. PATIENTS This 39-year-old woman and this 52-year-old man complained of paresthesia and burning pain, which worsened with walking, in the area of the sural nerve, about 1 month after saphenectomy of the small saphenous vein. RESULTS Exploratory surgery in both cases led to the identification of the spindle neuroma-in-continuity of the sural nerve confirmed histologically. The nerve was sectioned and the proximal stump implantated under the deep fascia. This resulted in complete remission of the symptoms in one case, and partial in the other. CONCLUSION It is likely that the nerve was lacerated during stripping, as a process of periphlebitis might cause adhesion of the vein to the nerve, and then the spindle neuroma developed. The authors underline the necessity of including neuroma of the sural nerve among the possible, albeit rare, complications of stripping of the small saphenous vein.

A elaboração de um trabalho cientifico não é tarefa simples, em virtude das diversas preocupações que os pesquisadores precisam ter no momento da realização do mesmo. Preocupações que vão desde a pesquisa propriamente dita, até escrita do documento. Para a escrita desses trabalhos, existem normas e padrões, que visam garantir uniformidade. Um dos problemas observados é que as normas sofrem constantes mudanças, que implica reaprendizado das mesmas, por parte de alguns pesquisadores. O Latex é uma ferramenta de apoio para produção de trabalhos científicos e destaca-se por possuir inúmeras vantagens. Contudo é deficiente em determinados aspectos. Este trabalho vem apresentar uma proposta de uma ferramenta computacional, que proporcione ao pesquisador uma abstração entre a pesquisa científica propriamente dita e o seu tratamento por escrito, fazendo com que o mesmo sinta-se a vontade para realizar sua pesquisa e redigir seu trabalho, não se preocupando com os formalismos e as constantes revisões ou alterações nas normas.