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Item Modeling and Forecasting Mortality in Sri Lanka(2014) Aberathna, Wasana; Alles, Lakshman; Wickremasinghe, W. N.; Hewapathirana, IsuruThe purpose of this study is to develop sex-specific mortality estimation models using historical mortality data for Sri Lanka, based on the statistical time series techniques attributed to Lee and Carter (1992). Historical mortality data was analyzed in the light of significant historical episodes. Several alternative univariate time series models were examined for modeling males and females, as well as a bivariate vector autoregressive (VAR) model. The VAR model when fitted to the first differenced series performed better than the univariate models and hence used for forecasting purposes. From the estimated VAR model, mortality forecasts were generated for the period up to 2030 and life tables were generated for the selected periods of 2006-2008.Item Change detection in dynamic attributed networks(2018) Hewapathirana, I.U.A network provides powerful means of representing complex relationships between entities by abstracting entities as vertices, and relationships as edges connecting vertices in a graph. Beyond the presence or absence of relationships, a network may contain additional information that can be attributed to the entities and their relationships. Attaching these additional attribute data to the corresponding vertices and edges yields an attributed graph. Moreover, in the majority of real-world applications, such as online social networks, financial networks and transactional networks, relationships between entities evolve over time. Change detection in dynamic attributed networks is an important problem in many areas, such as fraud detection, cyber intrusion detection, and health care monitoring. It is a challenging problem because it involves a time sequence of attributed graphs, each of which is usually very large and can contain many attributes attached to the vertices and edges, resulting in a complex, high-dimensional mathematical object. In this survey we provide an overview of some of the existing change detection methods that utilize attribute information. We categorize these methods based on the levels of structure in the graph that are exploited to detect changes. These levels are vertices, edges, subgraphs, communities, and the overall graph. We focus attention on the strengths and weaknesses of these methods, including their performance and scalability. Furthermore, we discuss some publicly available dynamic network datasets and give a brief overview of models to generate dynamic attributed networks. Finally, we discuss the limitations of existing approaches identifying key areas for future research.Item Architecting advanced devops engine with docker by using microservices for enterprise software applications(EdHat International, UK, 2019) Kithulwatta., W.M.C.J.T.; Jayawickrama., D.In the industry approach, bare-metal hardware, virtual machines (VMs) or cloud infrastructure are using to launch enterprise-ready applications. At the time of using those platforms, the main problems that occur are the difficulty of scaling the infrastructure and maintain the infrastructure, long-time data persisting issues, the difficulty in archiving the systems and large payments on cloud services. To overcome the identified problems, an advanced DevOps engine was developed on the Docker container management system with microservices applications. The objectives of this study are to develop conceptual and technical DevOps engine module, to apply the containerization platform on Docker engine for enterprise-ready microservices applications and to make an agile DevOps platform. The proposed system was analyzed over the cloud infrastructure with the same configurations. Jha, et al. (2018) describes that Docker is a better approach for microservices applications but there are no existing researches for microservices architecture for the enterprise-ready platform with DockerItem Enterprise Ready Containerized And Microservices Architectural Devops Engine Designing(2nd South Asia Conference on Multidisciplinary Research, 2019) Kithulwatta, W.M.C.J.T.; Jayawickrama, D.Seamlessly software delivery and maintaining without any delay, is the major task of DevOps engineers in industrialization. In the traditional way, it is using bare metal hardware or cloud services to farm the computer system infrastructure. While using those modules, the main problems arising are, huge cloud service charges, disability to use infrastructure in the cross-platform, difficulty of infrastructure migration, system archiving problem, data persisting problems and smooth scalability issue. Main objectives of the research study are to create portable system infrastructure modules, to create technical and theoretical containerized DevOps engine, apply long-time data persisting approach to the enterprise applications and to apply high-velocity innovation to the computer systems infrastructure. The proposed DevOps engine was designed with the Docker container management system on top of the Linux operating system as the host. It was used Docker trusted images to deploy, isolated containers by using microservices architecture with advanced software engineering concepts with industrialized software applications. It was used enterprise-ready software applications and services on the proposed engine to validate the concept over the same configurations on the cloud service. With the usage of encapsulated components container approach, all internal data was secured on top of the host operating system. Due to the portability of Docker containers, it was easy to migrate the monolithic computer system to microservices architecture. By using fast Docker containers, it was facilitated to DevOps engineers on the engine to improve the scalability and security across the system infrastructure.Item Solutions of Direct and Inverse Even-Order Sturm-Liouville Problems Using Magnus Expansion(Mathematics, 2019) Perera, U.; Böckmann, C.In this paper Lie group method in combination with Magnus expansion is utilized to develop a universal method applicable to solving a Sturm–Liouville problem (SLP) of any order with arbitrary boundary conditions. It is shown that the method has ability to solve direct regular (and some singular) SLPs of even orders (tested for up to eight), with a mix of (including non-separable and finite singular endpoints) boundary conditions, accurately and efficiently. The present technique is successfully applied to overcome the difficulties in finding suitable sets of eigenvalues so that the inverse SLP problem can be effectively solved. The inverse SLP algorithm proposed by Barcilon (1974) is utilized in combination with the Magnus method so that a direct SLP of any (even) order and an inverse SLP of order two can be solved effectively. View Full-TextItem Leishmaniasis: a vector- born disease in Sri Lanka: past, current and future(Gloria Scientiam – Golden Jubilee Commemorative Volume, Faculty of Science, University of Kelaniya, 2017) Ganehiarachchi, G.A.S.M; Nayakarathna, N.M.N.G.; Rajapakse, R.P.V.J.Leishmaniasis is caused by a protozoan parasite Leishmania species and is transmitted to humans by the bite of infected female phlebotomine (Diptera: Psychodidae) sand flies. There are three main forms of Leishmaniasis; Cutaneous Leishmaniasis, Muco-Cutaneous Leishmaniasis and Visceral Leishmaniasis. At present, Cutaneous Leishmaniasis is established in Sri Lanka. The parasite in this country is Leishmania donovani MON 37 and the prevalent vector is Phlebotomus argentipes. Environmental factors including temperature, humidity and rainfall influence the abundance and distribution of sand flies. Socio-economic conditions, population mobility, environmental and climate changes are the main risk factors of the spread of Leishmaniasis. Early detection of the disease and treatment, vector management and health education are the main control strategies for the control of the disease. It is a timely need to control the disease transmission before more virulent strains are established in the country. To resolve the epidemiology of Leishmaniasis further studies on the parasitic aspects and entomological studies of vector aspects are most important. Harmonizing with these biological phenomena, continuous surveillance, improving case detection programs at the community level and implementing management protocols and control activities are necessary to eliminate Leishmanisis in Sri LankaItem Effectiveness of protected areas in preventing rubber expansion and deforestation in Xishuangbanna, Southwest China(Land Degradation & Development, 2018) Sarathchandra, C.; Dossa, G.G.; Ranjitkar, N.B.; Chen, H.; Deli, Z.; Ranjitkar, S.; De Silva, K.H.W.L.; Wickramasinghe, S.; Xu, J.; Harrison, R.D.Protected areas (PAs) are supposedly key refuges for the world's remaining biodiversity. Our study site, Xishuangbanna, harbors a high proportion of China's biodiversity but is threatened by rapid deforestation and expansion of monoculture rubber. We quantified the success of Xishuangbanna's PAs in preventing deforestation.Most previous analyses of PA effectiveness have insufficiently accounted for biases arising from PA location and establishment, because they overlooked the importance of site‐matching in accounting for landscape change.We used matching methods to minimize such biases in comparing land use conversion rates inside and outside‐PAs. By 2010, Xishuangbanna had 3,455.5 km2 (~18%) designated as PAs. However, rubber occupied 22% of its land area and was expanding at a rate of 153.4 km2/year. Between 1988 and 2010, conventional analysis showed a deforestation rate of 9.3 km2/year. However, matching analysis showed a significantly higher rate of deforestation, 10.7 km2/year, which resulted in the deforestation of ~11% of PA's land. We argue that PAs were less effective than had previously been thought. The situation worsened from 2002 to 2010, when the deforestation rate within PAs was actually higher than that of outside PAs, although this difference was not significant. The designated higher levels of protection in ‘core’ zones were also unsuccessful in preventing deforestation. At current rates, within the next 50 years, a further 16% of PAs would be deforested in Xishuangbanna. This could even be an underestimate, as without intervention, drivers of deforestation tend to accelerate. Therefore, reviewing and strengthening current PA management policies is essential.Item Phylogenetic Revision of Savoryellaceae and Evidence for Its Ranking as a Subclass(Front. Cell. Infect. Microbiology, 2019) Dayarathne, M.C.; Maharachchikumbura, S.S.N.; Jones, E.B.G.; Dong, W.; Devadatha, B.; Yang, J.; Ekanayaka, A.H.; De Silva, W.; Sarma, VV.; Al-Sadi, A.M.; Khongphinitbunjong, K; Hyde, K.D.; Zhao, R.L.Morphology, phylogeny, and molecular clock analyses were carried out on Savoryellaceae in order to understand the placements of taxa in this family. Ascotaiwania and Neoascotaiwania formed a well-supported separate clade in the phylogeny of concatenated partial SSU, LSU, TEF, and RPB2 gene data. These two genera share similar morphological features, especially in their asexual morphs, indicating that they are congeneric. Hence, we synonymize Neoascotaiwania under Ascotaiwania. Ascotaiwania hughesii (and its asexual morph, Helicoon farinosum) and Monotosporella setosa grouped in a clade sister to Pleurotheciales and are excluded from Ascotaiwania which becomes monophyletic. A novel genus Helicoascotaiwania is introduced to accommodate Ascotaiwania hughesii and its asexual morph, Helicoon farinosum. A novel species, Savoryella yunnanensis is introduced from a freshwater habitat in Yunnan Province, China. Comprehensive descriptions and illustrations are provided for selected taxa in this family. In addition, we provide evolutionary divergence estimates for Savoryellomycetidae taxa and major marine based taxa to support our phylogenetic and morphological investigations. The taxonomic placement of these marine-based taxa is briefly discussed. Our results indicate that the most basal group of marine-based taxa are represented within Lulworthiales, which diverged from ancestral Sordariomycetes around 149 Mya (91–209) and Savoryellomycetidae around 213 Mya (198–303).Item Root-foraging behavior ensures the integrated growth of Vallisneria natans in heterogeneous sediments(Environmental Science and Pollution Research, 2017) Chen, J.; Hu, X.; Cao, T.; Zhang, X.; Xi, Y.; Wen, X.; Su, H.; De Silva, W.; Zhu, T.; Ni, L.; Xie, P.Abstract The present study was carried out to determine the efficacy of root foraging and the physiological response of Vallisnaria natans grown in heterogeneous sediments. V. natans was cultivated in two homogeneous and two heterogeneous sediments. The results suggested that V. natans grown in heterogeneous sediments presented a significantly higher root proportion in its total biomass, exhibited root foraging, and grew well, as indicated by a total biomass, ramet number, and plant height very close to those of plants grown in nutrient-rich clay sediment. Moreover, the more sensitive physiological response of the roots than the stems or the leaves to sediment nutrients suggested that root foraging occurred, and the approached values between the two heterogeneous sediments and the homogeneous clay sediment indicated that V. natans could satisfy its nutrient requirements via root foraging. The results may be useful in the recovery of macrophytes that remodel part (rather than all) of the substrate and can potentially improve habitats that are unsuitable for plant growth.Item Potential spreading risk of an invasive snail species (Pomacea canaliculata) in freshwater habitats of Asia(Current Science, 2019) De Silva, W.; Cao, T.; Wen, Z.; Zhang, X.; Ni, L.The invasive success of the freshwater snail species (Pomacea canaliculata) continues to wreak havoc around the world. The present study was initiated to analyse spatial trend and associated environmental conditions related to the invasive success of P. canaliculata in Asia. Systematic searches were performed to identify relevant studies through different databases, and appropriate statistical methods like spatial autocorrelation, standard deviational ellipse method and PCA were used to generate new knowledge on this species. The potential invasive range of this species is between 40°N and 40°S lat. The present study reveals that the spatial distribution of P. canaliculata is most significantly correlated with human population density, followed by humidity, temperature and precipitation. Moreover, the grazing rates are dramatically affected by nutrient content of freshwater macrophytes. Spatial autocorrelation analysis result indicates clustered dispersion pattern of this snail, and standard deviational ellipse depicts the invasion trend of P. canaliculata moving from East Asia to potential areas in South and West Asia. We therefore conclude that P. canaliculata is likely to be the ‘next harmful visitor’ to South and West Asian countries.