5,780 research outputs found
Inferring offline hierarchical ties from online social networks
No full textSocial networks can represent many different types of relationships between actors, some explicit and some implicit. For example, email communications between users may be represented explicitly in a network, while managerial relationships may not. In this paper we focus on analyzing explicit interactions among actors in order to detect hierarchical social relationships that may be implicit. We start by employing three well-known ranking-based methods, PageRank, Degree Centrality, and Rooted-PageRank (RPR) to infer such implicit relationships from interactions between actors. Then we propose two novel
approaches which take into account the time-dimension of interactions in the process of detecting hierarchical ties. We experiment on two datasets, the Enron email dataset to infer manager-subordinate relationships from email exchanges, and a scientific publication co-authorship dataset to detect PhD advisor-advisee relationships from paper co-authorships. Our experiments show that time-based methods perform considerably better than ranking-based methods. In the Enron dataset, they detect 48% of manager-subordinate ties versus 32% found by Rooted-PageRank. Similarly, in co-author dataset, they detect 62% of advisor-advisee ties compared to only 39% by Rooted-PageRank
Engineered railroad ties, U.S. Patent 7,011,253
No full textTo increase the resistance of plastic and/or plastic composite railroad ties to sliding within the ballast of the railroad bed, for example, sliding lengthwise (in the direction of the longitudinal axis of the tie) and sideways (in the direction perpendicular to the longitudinal axis), ties with a textured surface which aids in anchoring the ties within the ballast of the railroad beds. In particular, the ties are provided with a pattern of indentations within a surface that contacts the ballast which increases the ties resistance to sliding. The pattern is molded into the ties so as to mechanically interact with the ballast (rocks) and provide as much resistance to sliding as possible, especially along the longitudinal axis of the tie but also in the direction perpendicular to the longitudinal axis
The Treatment of Ties in AP Correlation
No full textThe Kendall tau and AP correlation coefficients are very commonly use to compare two rankings over the same set of items. Even though Kendall tau was originally defined assuming that there are no ties in the rankings, two alternative versions were soon developed to account for ties in two different scenarios: measure the accuracy of an observer with respect to a true and objective ranking, and measure the agreement between two observers in the absence of a true ranking. These two variants prove useful in cases where ties are possible in either ranking, and may indeed result in very different scores. AP correlation was devised to incorporate a top-heaviness component into Kendall tau, penalizing more heavily if differences occur between items at the top of the rankings, making it a very compelling coefficient in Information Retrieval settings. However, the treatment of ties in AP correlation remains an open problem. In this paper we fill this gap, providing closed analytical formulations of AP correlation under the two scenarios of ties contemplated in Kendall tau. In addition,we developed an R package that implements these coefficients.Best Short Paper Accepted author manuscriptMultimedia ComputingWeb Information System
Semantic Ties in the Text
Get PDFapplication/pdfDepartmental Bulletin PaperWithin the frame work of conceptual meaning, semantic ties in the text are discussed under the three headings of referential, logical and situational ties. 1) Referential ties are endophoric relation realized through substitution. 2) Logical ties are logical relation realized through marked conjunction. 3) Situational ties are unmarked relation between messages. By studying these ties, the author assumes, the resources for effective text composition will be provided.departmental bulletin pape
Prefabricated Vaults Strengthened with Ties
No full textThis paper describes the design of prefabricated low-rise barrel vaults strengthened with ties This paper describes the design of prefabricated low-rise barrel vaults strengthened with ties. Structurally barrel vaults are very efficient, so the need of material is pretty small. Probably in the coming decades the reduction of the environmental load of buildings by reducing the need of material will be most important again. Nowadays concrete barrel vaults are not built often anymore, mostly because of the cost of construction. Prefabrication will reduce the cost of labour, especially if the variation of the elements is restricted and the radius of the curvature of the vault is constant. Generally vaults following a circle segment are subjected to bending moments. Strengthening these vaults with ties is effective to reduce the bending moments. This paper focuses on the design of prefabricated low rise vaults, composed of circular segments and strengthened with slender ties to contribute to the architecturally concept and to reduce the dimensions, self-weight, need of material and environmental load.Building TechologyArchitecture and The Built Environmen
RUSSIAN PRODUCTION TIES DEVELOPMENT IN CONDITIONS OF REGIONAL INTEGRATION
No full textThe author analyzes development of «production ties» term and defines its meaning in modern economy, she also emphasizes main factors influencing production ties. Production cooperation is the most wide - spread and effective way of production ties of enterprises, it consolidates economic interests of economic entities of all levels. The author analyses main directions of Russian production ties development and defines production cooperation of Russia with other countries in the conditions of regional integration
Analytical calculation model for predicting cracking behavior of reinforced concrete ties
No full textThis paper formulates an analytical calculation model for predicting the cracking behavior of reinforced concrete ties to provide more consistent crack width calculation methods for large-scale concrete structures in which large bar diameters and covers are used. The calculation model was derived based on the physical behavior of reinforced concrete ties reported from experiments and finite-element analyses in the literature. The derivations led to a second order differential equation for the slip that accounts for the three-dimensional effects of internal cracking by using a proper bond-slip law. The second order differential equation for the slip was solved completely analytically, resulting in a closed-form solution in the case of lightly loaded members and in a non-closed-form solution in the case of heavily loaded members. Finally, the paper provides a solution strategy to facilitate a practical and applicable method for predicting the complete cracking response. Comparison with experimental and finite-element results in the literature demonstrated the ability of the calculation model to predict crack widths and crack spacing consistently and on the conservative side regardless of the bar diameter and cover.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Applied Mechanic
Dealing with Ties in Rank Correlation
No full textIn the field of Information Retrieval (IR), rankings of systems evaluated under different conditions are often compared to each other. This measure of correspondence between rankings, termed as rank correlation, must accurately capture the scenario for which the correlation is computed. Very often, these rankings may have tied systems, for which new correlation coefficients arise. It is important that these coefficients account for the new scenarios in the presence of ties. It is also important that these coefficients provide some flexibility to the person performing the correlation to introduce artificial ties when items are so close to each other that, for practical purposes, they may be considered as tied. Accounting for these different scenarios of tied items in rankings permits performing per topic comparisons of IR systems, which was earlier limited due to the presence of ties on individual topics. Comparing rankings at the topic level, the expected variability of the rankings can be studied to potentially improve the systems on the topics for which they perform poorer than average. We show the application of these new correlation coefficients with two typical IR experiments.Computer Science | Multimedia Computin
The strength of long ties and the weakness of strong ties: Knowledge diffusion through supply chain networks
No full textAbstractUsing a large firm-level panel dataset for Japan, this paper examines the effects of the structure of supply chain networks on productivity and innovation capability through knowledge diffusion. We find that ties with distant suppliers improve productivity (as measured by sales per worker) more than ties with neighboring suppliers, which is likely because distant firms’ intermediates embody more diversified knowledge than those from neighboring firms. Ties with neighboring clients improve productivity more than ties with distant clients, which is likely because neighboring clients more effectively diffuse disembodied knowledge than distant clients. By contrast, ties with distant suppliers and clients improve innovative capability (as measured by the number of registered patents), whereas ties with neighboring suppliers or clients do not affect innovative capability. In addition, the density of a firm's ego network (as measured by how densely its supply chain partners transact with one another) has a negative effect on productivity and innovative capability, implying knowledge redundancy in dense networks. These results suggest that access to diversified ties is important for improving productivity and innovation capability through knowledge diffusion
Experimental and theoretical investigation of crack width calculation methods for RC ties
No full textThis paper theoretically and experimentally investigates the semi-empirical formulas recommended by Eurocode 2 (EC2), fib Model Code 2010 (MC2010), and Eurocode 2 with the German National Annex (DIN) for calculating crack widths in reinforced concrete. It is shown that the formulas can be derived from the principles for the idealized behavior of RC ties. However, instead of explicitly solving the resulting differential equations, the use of simplifications leads to inconsistent formulas. An experimental study was carried out involving the testing of eight RC ties to discover the modeling uncertainty of the formulas. It was found that EC2 substantially overestimated the crack widths for the RC ties. MC2010 and DIN seemed to predict the crack widths better, but gave rather a large number of nonconservative crack width predictions. These experimental results, combined with the theoretical study, suggest that a more consistent calculation model should be formulated by explicitly solving the resulting differential equation.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Applied Mechanic
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