110 research outputs found

    Enhanced border gateway protocol in NS- 2 by adding the hot potato functionality based on real network

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    The rapid growth of the Internet has made the issue of ensuring reliability and redundancy a big challenge. Studies of these issues using Traffic Engineering and simulation have been extensively done. There has been substantial interest from researchers in the development and contribution of modules in NS-2. Most studies have not taken into account real traffic parameters in their simulation models. Also, there is no comprehensive model consisting of Border Gateway Protocol (BGP) and Hot Potato (HP) routing in the NS-2 network simulator based on real networks. In this paper, Integrated Model is introduced consisting of HP algorithm and BGP integrated into the NS-2 network simulator. The integrated model is then used to simulate the infrastructure of a real production network using actual captured traffic data parameters. The network is modeled with a baseline topology where 5 main nodes were connected together, with redundant links for some nodes. The simulations were repeated for link failures. HP helps in improving the node which experiences a link failure to select shorter distance route to egress router. In the case of a link failure, HP switching time between the links is 0.05 seconds. The integrated model performance was evaluated by comparing trace file before and after link failure or by adding nodes (up to 32). The parameters used for comparison are the packets loss, delay and throughput. The integrated model error percentage obtained for packets loss is 0.025%, delay 0.013% and throughput 0.003%

    BioPhysConnectoR: Connecting Sequence Information and Biophysical Models

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    <p>Abstract</p> <p>Background</p> <p>One of the most challenging aspects of biomolecular systems is the understanding of the coevolution in and among the molecule(s).</p> <p>A complete, theoretical picture of the selective advantage, and thus a functional annotation, of (co-)mutations is still lacking. Using sequence-based and information theoretical inspired methods we can identify coevolving residues in proteins without understanding the underlying biophysical properties giving rise to such coevolutionary dynamics. Detailed (atomistic) simulations are prohibitively expensive. At the same time reduced molecular models are an efficient way to determine the reduced dynamics around the native state. The combination of sequence based approaches with such reduced models is therefore a promising approach to annotate evolutionary sequence changes.</p> <p>Results</p> <p>With the <monospace>R</monospace> package <monospace>BioPhysConnectoR</monospace> we provide a framework to connect the information theoretical domain of biomolecular sequences to biophysical properties of the encoded molecules - derived from reduced molecular models. To this end we have integrated several fragmented ideas into one single package ready to be used in connection with additional statistical routines in <monospace>R</monospace>. Additionally, the package leverages the power of modern multi-core architectures to reduce turn-around times in evolutionary and biomolecular design studies. Our package is a first step to achieve the above mentioned annotation of coevolution by reduced dynamics around the native state of proteins.</p> <p>Conclusions</p> <p><monospace>BioPhysConnectoR</monospace> is implemented as an <monospace>R</monospace> package and distributed under GPL 2 license. It allows for efficient and perfectly parallelized functional annotation of coevolution found at the sequence level.</p

    Using geographically weighted regression to explore neighborhood-level predictors of domestic abuse in the UK

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    Reducing domestic abuse has become a priority for both local and national governments in the UK, with its substantial human, social, and economic costs. It is an interdisciplinary issue, but to date there has been no research in the UK that has focused on neighborhood-level predictors of domestic abuse and their variation across space. This article uses geographically weighted regression to model the predictors of police-reported domestic abuse in Essex. Readily available structural and cultural variables were found to predict the domestic abuse rate and the repeat victimization rate at the lower super output area level and the model coefficients were all found to be non-stationary, indicating varying relationships across space. This research not only has important implications for victims' well being, but also enables policy makers to gain a better understanding of the geography of victimization, allowing targeted policy interventions and efficiently allocated resources

    LOSS OF JAK2 REGULATION VIA VHL-SOCS1 E3 UBIQUITIN HETEROCOMPLEX UNDERLIES CHUVASH POLYCYTHEMIA

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    Chuvash polycythemia (CP) is a rare congenital form of polycythemia caused by homozygous R200W and H191D mutations in the von Hippel-Lindau (VHL) gene whose gene product is the principal negative regulator of hypoxia-inducible factor. However, the molecular mechanisms underlying some of the hallmark features of CP such as hypersensitivity to erythropoietin are unclear. Here, we show that VHL directly binds suppressor of cytokine signalling 1 (SOCS1) to form a heterodimeric E3 ligase that targets phosphorylated (p)JAK2 for ubiquitin-mediated destruction. In contrast, CP-associated VHL mutants have altered affinity for SOCS1 and fail to engage and degrade pJAK2. Systemic administration of a highly selective JAK2 inhibitor, TG101209, reverses the disease phenotype in vhlR200W/R200W knock-in mice, a model that faithfully recapitulates human CP. These results reveal VHL as a SOCS1-cooperative negative regulator of JAK2 and provide compelling biochemical and preclinical evidence for JAK2- targeted therapy in CP patients

    Geometric effects of sustainable auxetic structures integrating the particle swarm optimization and finite element method

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    The development of new materials based on industrial wastes has been the focus of much research for a sustainable world. The growing demand for tyres has been every year exacerbating environmental problems due to indiscriminate disposal in the nature, making a potentially harmful waste to public health. The incorporation of rubber particles from scrap tyres into polymeric composites has achieved high toughness and moderate mechanical properties. This work investigates the geometric effects (thickness, width and internal cell angle) of auxetic structures made of recycled rubber composites based on experimental and numerical data. The response surface models integrated with the swarm intelligence and finite element analysis were proposed in order to obtain a range of solutions that provides useful information to the user during the selection of geometric parameters for reentrant cells. The results revealed the cell thickness ranges from 39-40 mm and 5.98-6 mm, and the cell angle range from -0.01 to -0.06º maximize the ultimate strength. The same parameters were able to optimize the modulus of elasticity of rubber auxetic structures, excepting for the angle factor which must be set between -30º and 27.7º. The optimal Poisson's ratio was found when the cell angle ranged from -30º to -28.5º, cell width ranged from 5-5.6 mm and 2 mm in thickness

    Effects of implementation of environmental management system, fulfilling requirements of ISO 14001, in selected organizations

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    W artykule przedstawiono podstawowe wyniki pracy statutowej wykonanej w GIG, w celu określenia efektów ekonomicznych, ekologicznych i społecznych, uzyskanych przez wybrane organizacje w wyniku wdrożenia systemu zarządzania środowiskowego, zgodnego z wymaganiami normy ISO 14001. Badania prowadzono w firmach biorących udział w latach 2002-2003 w projekcie "Zarządzanie środowiskowe w Europie Wschodniej. Przemysł tworzyw sztucznych. Polska", finansowanym przez Duńską Agencję Handlu i Przemysłu.This paper presents basic results of the Central Mining Institute statutory research work. The aim of the work was to determine economic, ecological and social effects, obtained by the selected organisations as the result of implementation of environmental management system, according to the requirements of ISO 14001 standard. The research was carried out in co-operation with companies which participated in the project "Environmental Management in Eastern Europe. Plastics Industry Poland" in 2002-2003, financed by the Danish Agency for Trade and Industry

    Implementation of the Regional Environmental Management System in the Tarnowskie Góry Region

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    Zasada zrównoważonego rozwoju jest jedną z podstawowych zasad zapisanych w Konstytucji Rzeczpospolitej Polskiej. Przez zrównoważony rozwój rozumie się kompleksowe działania powodujące wzrost gospodarczy, przy jednoczesnym uwzględnieniu wymagań z zakresu ochrony środowiska. Istnieje wiele niesformalizowanych (np. Czystsza Produkcja), jak i sformalizowanych (ISO 14001, EMAS) systemów zarządzania środowiskowego, które służą do realizacji zasady zrównoważonego rozwoju. Wdrażanie systemów zarządzania środowiskowego w pojedynczych organizacjach stanowi bardzo ważny krok na drodze do zachowania lub poprawy stanu środowiska. Jednak dopiero wdrożenie zarządzania środowiskowego w skali regionalnej pozwala na pełne wykorzystanie atutów systemowego podejścia do zagadnień ochrony środowiska. W artykule przedstawiono, opracowany w Krajowym Centrum Wdrożeń Czystszej Produkcji GIG, model regionalnego systemu zarządzania środowiskowego. Podstawę modelu systemu stanowią dwie sprzężone ze sobą procedury operacyjne. Procedury opracowano wykorzystując podstawowe zasady Czystszej Produkcji oraz wymagania i zalecenia wybranych norm ISO, dotyczących zarządzania środowiskowego (ISO 14001, ISO 14031). Na podstawie opracowanego modelu, w ramach działalności statutowej GIG, wdrożono regionalny systemu zarządzania środowiskowego w powiecie oraz miastach i gminach powiatu tarnogórskiego w województwie śląskim. Proces wdrażania systemu obejmował serię interaktywnych modułów szkoleniowych, w których brali udział przedstawiciele powiatu oraz miast i gmin wchodzących w skład powiatu tarnogórskiego. Pomiędzy kolejnymi modułami szkoleniowymi, przedstawiciele powiatu oraz miast i gmin opracowywali sukcesywnie dokumenty systemu zarządzania środowiskowego. Opracowano, miedzy innymi, takie elementy systemu, jak: wstępny przegląd środowiskowy, rejestr aspektów środowiskowych, polityka środowiskowa, zestawienie wskaźników środowiskowych, rejestr celów i zadań środowiskowych oraz program zarządzania środowiskowego. Funkcjonowanie regionalnego systemu zarządzania środowiskowego, zainicjowanego w powiecie tarnogórskim wiąże się z realizacją konkretnych zadań, ujętych w programie zarządzania środowiskowego. Efekty działalności środowiskowej w powiecie oraz miastach i gminach powiatu tarnogórskiego będą monitorowane przez Krajowe Centrum Wdrożeń Czystszej Produkcji GIG po roku, od chwili wdrożenia regionalnego sytemu zarządzania środowiskowego.The principle of sustainable development is one of the basic notions mentioned in the Polish Constitution. The sustainable development stands for implementation of complex of procedures stimulating economic growth without compromising environmental safety requirements. There are formalized environmental management systems (ISO 14001, EMAS) as well as many not that formalized such as Cleaner Production. Implementation of environmental management systems in separate organizations constitutes an important step towards improvement of environmental safety. However, the benefits of the system approach to environmental issues can be achieved in full only when an environmental management system is applied in a regional scale. In this paper the regional model of environmental management system is presented, elaborated in the National Center for Implementation of Cleaner Production. The basis of the system is formed by two coupled operational procedures. These procedures were elaborated basing on key rules of Cleaner Production as well as on requirements and recommendations of some chosen ISO standards concerning environmental management (ISO 1401, 1431). On the basis of that model an environmental management system was implemented in cities and communes of the Tarnowskie Góry region in the Silesia voivodeship. The implementation process involved a series of interactive training modules carried out for the representatives of the region, its cities and communes. The documents of the regional system were prepared by the participants after each training module. Among others the following elements of the system were elaborated: initial environmental survey, environmental aspects register, environmental policy, set of environmental indications, roster of environmental aims and tasks and environmental management program. The regional environmental management system initiated in the Tarnowskie Góry region is being realized as a series of concrete tasks set out in the environmental management program. Twelve months after the full implementation of the system the results of environmental activity in the region and its communes will be checked by the National Center for Implementation of Cleaner Production

    Stress corrosion - when the defect depth is important

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    Scharakteryzowano zjawisko korozji naprężeniowej pod kątem możliwości detekcji klasycznymi metodami NDT. Opisano metodę wiroprądową z zastosowaniem sondy macierzowej w kontekście wykrywania niezgodności spowodowanych korozją naprężeniową. Zaprezentowano system kompensacji zmiany odległości cewki od powierzchni oraz możliwości wymiarowania. Przedstawiono charakterystykę przykładowej głowicy oraz przedstawiono wyniki pomiaru na elemencie referencyjnym i rzeczywistym. Przedstawione wyniki wykazują wysoką skuteczność w wykrywaniu niezgodności powstałych w wyniku korozji naprężeniowej. Ostatecznie dokonano porównania wyników uzyskanych metodą prezentowaną oraz metodami magnetyczno-proszkową i ultradźwiękową.The stress corrosion cracking phenomena has been characterized in terms of detection capabilities by classical NDT methods. An eddy current method using a array probe has been described in the context of detecting flaws caused by stress corrosion. A compensation system for changes of the probe lift-off distance and the dimensioning capability was presented. The characteristics of the sample head are shown and the measurement results are presented on the reference and real elements. The results shown are highly effective in detecting flaws caused by stress corrosion. Finally, the results obtained by the presented method with the ones of magnetic penetrant and ultrasonic methods were compared
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