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Sweet potato [Ipomoea batatas (L.) Lam.] varieties can be distinguished by their flesh and skin colors (white, yellow, orange, and purple). The present study was undertaken to assess on-farm diversity and the status of genetic erosion of sweet potatoes in Haramaya district, Ethiopia. Data were collected for similarity/dissimilarity index, preference index, and genetic erosion. The result of the preference index indicated the highest preference index (25.60) with preference rank 1 recorded for the BeelaBochol genotype as the lowest preference index (12.10) was recorded for the BeelaBaleyso genotype. About 66% of the respondents use the intercropping system for sweet potato cultivation. The majority of respondents 97% observed loss of sweet potato varieties. Eighty-two percent of the respondent farmers suggested the use of their seed source for planting. About 73% of the respondents suggested the cultivation of sweet potato as a subsistence crop. The major constraints of sweet potato cultivation, as suggested by the respondents, were tiresome land preparation 37%, lack of improved variety 26%, land scarcity 23%, and market demand 15%. It can be concluded from the result of the present study that farmers can identify and prefer sweet potato genotypes frequently using storage root yield and boiled quality. [ABSTRACT FROM AUTHOR]

The American National Standards Institute/American Nuclear Society national standards 8.1 and 8.24 provide guidance on the requirements and recommendations for establishing confidence in the results of the computerized models used to support operation with fissionable materials. By design, the guidance is not prescriptive, leaving freedom to the analysts to determine how the various sources of uncertainties are to be statistically aggregated. Due to the involved use of statistics entangled with heuristic recipes, the resulting safety margins are often difficult to interpret. Also, these technical margins are augmented by additional administrative margins, which are required to ensure compliance with safety standards or regulations, eliminating the incentive to understand their differences. With the new resurgent wave of advanced nuclear systems, e.g., advanced reactors, fuel cycles, and fuel concepts, focused on economizing operation, there is a strong need to develop a clear understanding of the uncertainties and their consolidation methods to reduce them in manners that can be scientifically defended. In response, the current studies compare the analyses behind four notable methodologies for upper subcriticality limit estimation that have been documented in the nuclear criticality safety literature: the parametric, nonparametric, Whisper, and TSURFER methodologies. Specifically, the work offers a deep dive into the various assumptions of the noted methodologies, their adequacies, and their limitations to provide guidance on developing confidence for the emergent nuclear systems that are expected to be challenged by the scarcity of experimental data. To limit the scope, the current work focuses on the application of these methodologies to criticality safety experiments, where the goal is to calculate a bias, a bias uncertainty, and a tolerance limit for keff in support of determining an upper subcriticality limit for nuclear criticality safety. [ABSTRACT FROM AUTHOR]

A Recommendation System (RS) is a method which filters the information and helped users' to choose the corresponding target from the huge amount of information obtainable in online. The system recommends useful and satisfactory products (items) such as books, music, jokes, and movies for targeting users based on their interest. The content-based filtering as well as collaborative are different systems used often while designing the RS that predicts the recommended item(s) based upon the user preferences. However, the collaborative filtering algorithm provides poor performance for data sparsity, and it is complex for tracking the change of user interest. Moreover, the hybrid system has combined both the techniques in multiple ways to overcome the shortcomings and optimize the outcomes. Thereby, this article plans to develop a new hybrid recommender system assisting with the optimization concept for optimal recommendation list based on user preference or interest. At first, the feature extraction process takes place, in which the content features and the collaborative features are extracted based on (a) profile construction, (b) content similarity index, (c) Neighbor finder, (d) Items generator, and (e) Items weight generator and variance generator. Consequently, the optimal recommendation is carried out on the basis of features extracted. Further, the developed work plans to carry out the optimal rating of recommendation using a FireFly with Weighted Crow Search Algorithm (FF-WCSA). At last, the outcomes of the developed model is computed to extant approaches in terms of various metrics like accuracy, FDR, MAE, MARE, MSE, MSRE, RMSE, and RMSRE, respectively. [ABSTRACT FROM AUTHOR]

Using Comtrade data extrapolated by the Trade Map system, this article presents different indexes to provide a picture of the evolution of similarities, productive dependence, and comparative advantages between the exports and imports of European Union (EU) and Asian countries. The findings indicate that 67% of the 24 agri‐food products considered in the EU‐28 show a comparative advantage for Asian markets. Furthermore, the results obtained from the application of a multivariate analysis offer a new insight, demonstrating an increase over the last decade in interdependence, similarity, and integration, firstly between some Asian countries and secondly between some EU and Asian countries. [ABSTRACT FROM AUTHOR]

The story of statistics in geotechnical engineering can be traced to Lumb's classical Canadian Geotechnical Journal paper on "The Variability of Natural Soils" published in 1966. In parallel, the story of risk management in geotechnical engineering has progressed from design by prescriptive measures that do not require site-specific data, to more refined estimation of site-specific response using limited data from site investigation as inputs to physical models, to quantitative risk assessment (QRA) requiring considerable data at regional/national scales. In an era where data is recognised as the "new oil", it makes sense for us to lean towards decision making strategies that are more responsive to data, particularly if we have zettabytes coming our way. In fact, we already have a lot of data, but the vast majority is shelved after a project is completed ("dark data"). It does not make sense to reduce one zettabyte to a few bytes describing a single cautious value. It does not make sense to expect big data to be precise and to fit a particular favourite physical model as demanded by the classical deterministic world view. This paper advocates the position that there is value in data of any kind (good or not so good quality, or right or wrong fit to a physical model) and the challenge is for the new generation of researchers to uncover this value by hearing what data have to say for themselves, be it using probabilistic, machine learning, or other data-driven methods including those informed by physics and human experience, and to re-imagine the role of the geotechnical engineer in an immersive environment likely to be imbued by machine intelligence. [ABSTRACT FROM AUTHOR]

Finding the number of clusters in a data set is considered as one of the fundamental problems in cluster analysis. This paper integrates maximum clustering similarity (MCS), for finding the optimal number of clusters, into R © statistical software through the package MCSim. The similarity between the two clustering methods is calculated at the same number of clusters, using Rand [Objective criteria for the evaluation of clustering methods. J Am Stat Assoc. 1971;66:846–850.] and Jaccard [The distribution of the flora of the alpine zone. New Phytologist. 1912;11:37–50.] indices, corrected for chance agreement. The number of clusters at which the index attains its maximum with most frequency is a candidate for the optimal number of clusters. Unlike other criteria, MCS can be used with circular data. Seven clustering algorithms, existing in R © , are implemented in MCSim. A graph of the number of clusters vs. clusters similarity using corrected similarity indices is produced. Values of the similarity indices and a clustering tree (dendrogram) are produced. Several examples including simulated, real, and circular data sets are presented to show how MCSim successfully works in practice. [ABSTRACT FROM AUTHOR]

Sustainable management of plant diversity in a forest requires adequate information that is often derived from samples. With limited resources, the plot design has to be efficient. Most studies focused on evaluating effects of plot designs on sample estimates of species richness at landscape scale. This study aims at filling a knowledge gap by investigating how plot size and shape affect sample estimates of species composition at a local scale. Two census datasets with distinct forest ecosystems were used. Fifteen combinations of plot size and shape were simulated. Species compositional similarity between two combinations of plot design at a sample point was estimated by Jaccard and Sørensen indices, and their abundance-adjusted counterparts. Similarity in species composition decreased with increasing difference between two plot sizes. Plots with varying shapes were found to have different local species composition but could be similar in the number of observed species, which has not been explicitly reported elsewhere. For less species-rich forests, a 0.025-0.05 ha circular plot is recommended. For species-rich forests, a 0.05-0.1 ha rectangular plot with aspect ratio of at least 1:20 is recommended. The results should be of interest to stakeholders managing small area forests for conservation of plant diversity. [ABSTRACT FROM AUTHOR]

The present paper aims to explore the competition in exports among ASEAN + 3 members by applying the export similarity index for the disaggregation export data from 1990 to 2014. We also discuss the changes of comparative advantage of ASEAN + 3's exports through the revealed comparative advantage index and its relation with similarity index. First, the results support the idea that export similarity varies among ASEAN + 3 member states over the period 1990–2014. Second, we find evidence of several export communities. In particular, five countries, notably China, Japan, Malaysia, Singapore and South Korea, with the highest similarity index form an export community mainly in the electronic microcircuits and parts of office machines. Third, the revealed comparative advantage seems to be the key factor defining the similarity level of exports. Finally, the revealed comparative advantage analysis partly allows us to verify the Ricardo's theory and New Trade theory in the context of ASEAN + 3 trade integration. [ABSTRACT FROM PUBLISHER]

Water quality and ecological diversity of aquatic flora with respect to distribution in active channels and on banks of the rivers Ghaghara and Gandak have been investigated in years 2011–2012. The land use/land cover map of year 2010 showed agricultural land as the dominant class in both river basins. The appraisal of aquatic flora has indicated that the dominant plant species in numbers are as follows: macrophytic algae, aquatic angiosperms, aquatic pteridophytes, sedges, grasses, herbs, shrubs, climbers and trees collected from the banks and active channels of rivers Ghaghara and Gandak. In total, 207 plants species were reported as common in both river environments, and the remaining species have showed variability for both rivers. It was observed that the algal group showed higher species diversity in comparison to other plant groups. High numbers of macrophytic species were observed due to the alkaline pH and good level of dissolved oxygen at different sampling sites of the two rivers. Further, multivariate statistical techniques such as cluster analysis and principal component/factor analysis were applied to fulfil the knowledge gap and to identify the potential sources and types of pollutants. [ABSTRACT FROM PUBLISHER]

Species diversity indices are designed to measure the species diversity of a community and to compare the species distribution structure of two communities. The Shannon and Simpson indices are for describing one community, and the Jaccard and Morisita indices are for comparing two communities. Only a few indices allow the simultaneous comparison of three or more communities. In this study, we propose a multiple-community similarity index based on a probabilistic approach, and compare it with other multiple-community indices. Empirical examples are considered as a demonstration of the proposed similarity indices. [ABSTRACT FROM AUTHOR]

The present study accounts for the successional changes that took place in vegetation structure and composition over a time span of 25 years at reclaimed manganese mine site. Adjoining natural forest site was also studied for comparison of floral composition. The results corroborate the fact that as the age of succession increases, the reclaimed area gets invaded by higher successional species leading to an ecologically sound self-sustaining restructured system. This is an indication of the efficacy of the restoration programme. Plant species diversity of reclaimed site was 3.34, 2.81 and 2.12 for herbs, shrubs and trees, respectively, whereas in the adjoining natural forest site (Pench national park, reserved forest), it was 2.74, 1.88 and 2.13 for herbs, shrubs and trees, respectively. Phytodiversity assessments at both sites led to the conclusion that higher values of importance value index (IVI) were obtained for shrubs and herbs at the reclaimed site when compared to the adjoining natural forest site. However, higher values of tree diversity and IVI were associated with the natural forest site than the 25-year-old reclaimed site. This paper compares the composition of flora, species diversity and rapid succession of phytodiversity of a 25-year-old reclaimed site with nearby natural reserved forest site. Plant species richness of reclaimed site was 141, 38 and 18 for herbs, shrubs and trees, respectively, as compared to reserved forest site values of 55, 11 and 20 for herbs, shrubs and trees, respectively. Also, this paper evaluates the total and available nutrient, and microbial diversity in both the newly formed ecosystem and the adjacent natural forest site. [ABSTRACT FROM PUBLISHER]

Fewster and Buckland (2001) defined a similarity index between two communities by allowing changes between sites to reduce the influence of local discrepancies. The similarity index of Fewster and Buckland is calculated to attain the maximum similarity between two communities in the presence of migration. Instead of maximizing similarity, we propose random migration to measure the similarity of two communities with two types of stochastic migration. The similarity values based on the proposed methods can be treated as the expected value of similarity under migration. We use computer simulation and empirical examples to demonstrate our approach. [ABSTRACT FROM AUTHOR]

In today's world industrial companies commonly optimize several responses simultaneously to fit products to consumer needs. The preselection of the factors impacting those responses is however still a complex and critical step. Although screening designs exist to handle this issue, such techniques weaken when faced with an increasing number of responses (near or above 10). Therefore, we here present a complementary method to overcome two major drawbacks. On one hand, we increase the understanding of the structure of factor impact on responses and the lines and columns of the matrix resulting from the analysis of variance of the screening design are reorganized by cluster analysis. On the other hand, we select the subset of important factors by using a hierarchy tree of the factors built from the indices of frequency and similarity. We prove the efficiency of the method on a food industry example by selecting three out of nine cooking process parameters to optimize a 14 characteristic profile of an extruded product. [ABSTRACT FROM AUTHOR]

There are several indices for measuring the similarity of two populations, including the ratio of the number of shared species to the number of distinct species (Jaccard's index) and the conditional probability of observing a shared species (Smith et al., 1996). However, these indices only take into account the number of species and species proportions of shared species. In this article, we propose a new similarity index which includes the species proportions of both the shared and non shared species in each population, and also propose a Nonparametric Maximum Likelihood Estimator (NPMLE) for this index. Bootstrap and delta methods are used to evaluate the standard errors of the NPMLE. Based on a loss function, we also compare a class of nonparametric estimators for the proposed index in various situations. [ABSTRACT FROM AUTHOR]

Mahenge Mountain is part of the Eastern Arc Mountains in Tanzania. It is bordered by the Kilombero flood plain to the west and forms a continuous mountain block with the Mbarika to the south, lying close to the Udzungwa and Southern Highland Mountain blocks. The amphibian fauna of the forests of Mahenge Mountain has not been investigated until recent fieldwork carried out in the Sail Forest Reserve that has revealed a diverse forest fauna. In this study new records are reported, details of habitats are given and a checklist of the amphibians and reptiles of Mahange Mountain are provided. In addition, biogeographical analyses were carried out to investigate patterns of spatial turnover in species. This was achieved by calculating the standard similarity index between the amphibian assemblages of the highland Mahenge Mountains (<850 m) and the lowland Kilombero floodplain (<400 m). The results show significant differences (62%) between the two areas, reflecting large altitudinal turnover in species between the widespread lowland fauna and the montane fauna. This is further emphasized by a comparison of transects in lowland Mozambique and highland Zimbabwe, which has a comparable similarity index measure of 54%, impressive when comparing the difference in distance and altitude between the two transects. The reasons for this marked lowland-highland differentiation in Tanzania are poorly understood. Concern is raised for the preservation of this highland endemic fauna in the light of continuing habitat destruction. [ABSTRACT FROM AUTHOR]

Estimating the stability of microbial community structures may be useful in advanced biological wastewater treatment system design and operation. In this research, a monitoring method using fatty acid profiles was evaluated for detecting changes in microbial community structures. For the evaluation, the operating parameters such as pH, organic loading, and chlorine addition were varied in two identical laboratory scale conventional activated sludge systems. A similarity index based on microbial fatty acid analysis was used to express the stability of microbial community structures in the systems. Experiments using a model microbial community showed that microbial compositions changed daily even under constant operating conditions and that the rate of change increased under dynamic operating conditions. Substrate changes brought about a relatively large change in a microbial community structure, eventually resulting in a very different microbial community. After only 7 days following a substrate change in a lab-scale bioreactor, the biomass exhibited only 45% similarity to the original structure. The analysis of microbial fatty acids conveys additional information, in that it could be used for the calculation of biomass concentrations in a wastewater treatment system if microbial fatty acid analyses are executed on a routine basis as a monitoring tool for biological wastewater treatment systems. The total fatty acid concentrations were about 0.61% of the biomass concentration as mixed liquor volatile suspended solid concentrations in this research. [ABSTRACT FROM AUTHOR]