A Convex Reconstruction Model for X-ray Tomographic Imaging with Uncertain Flat-fields

Classical methods for X-ray computed tomography are based on the assumption that the X-ray source intensity is known, but in practice, the intensity is measured and hence uncertain. Under normal operating conditions, when the exposure time is sufficiently high, this kind of uncertainty typically has a negligible effect on the reconstruction quality. However, in time- or dose-limited applications such as dynamic CT, this uncertainty may cause severe and systematic artifacts known as ring artifacts. By carefully modeling the measurement process and by taking uncertainties into account, we derive a new convex model that leads to improved reconstructions despite poor quality measurements. We demonstrate the effectiveness of the methodology based on simulated and real data sets.Comment: Accepted at IEEE Transactions on Computational Imagin

Generating Abstractive Summaries from Meeting Transcripts

Summaries of meetings are very important as they convey the essential content of discussions in a concise form. Generally, it is time consuming to read and understand the whole documents. Therefore, summaries play an important role as the readers are interested in only the important context of discussions. In this work, we address the task of meeting document summarization. Automatic summarization systems on meeting conversations developed so far have been primarily extractive, resulting in unacceptable summaries that are hard to read. The extracted utterances contain disfluencies that affect the quality of the extractive summaries. To make summaries much more readable, we propose an approach to generating abstractive summaries by fusing important content from several utterances. We first separate meeting transcripts into various topic segments, and then identify the important utterances in each segment using a supervised learning approach. The important utterances are then combined together to generate a one-sentence summary. In the text generation step, the dependency parses of the utterances in each segment are combined together to create a directed graph. The most informative and well-formed sub-graph obtained by integer linear programming (ILP) is selected to generate a one-sentence summary for each topic segment. The ILP formulation reduces disfluencies by leveraging grammatical relations that are more prominent in non-conversational style of text, and therefore generates summaries that is comparable to human-written abstractive summaries. Experimental results show that our method can generate more informative summaries than the baselines. In addition, readability assessments by human judges as well as log-likelihood estimates obtained from the dependency parser show that our generated summaries are significantly readable and well-formed.Comment: 10 pages, Proceedings of the 2015 ACM Symposium on Document Engineering, DocEng' 201

Explicitly correlated Gaussian functions with shifted-center and projection techniques in pre-Born-Oppenheimer calculations

Numerical projection methods are elaborated for the calculation of eigenstates of the non-relativistic many-particle Coulomb Hamiltonian with selected rotational and parity quantum numbers employing shifted explicitly correlated Gaussian functions, which are, in general, not eigenfunctions of the total angular momentum and parity operators. The increased computational cost of numerically projecting the basis functions onto the irreducible representations of the three dimensional rotation-inversion group is the price to pay for the increased flexibility of the basis functions. This increased flexibility allowed us to achieve a substantial improvement for the variational upper bound to the Pauli-allowed ground-state energy of the H$_3^+=\{$p$^+,$p$^+,$p$^+,$e$^-,$e$^-\}$ molecular ion treated as an explicit five-particle system. We compare our pre-Born-Oppenheimer result for this molecular ion with rovibrational results including non-adiabatic corrections.Comment: 29 pages, 3 figures, 4 table

Business strategy and performance in Indonesia’s service sector

© 2016, © Emerald Group Publishing Limited. PurposeThe relationship between strategic choices and performance in service firms in emerging markets has remained largely under-researched. This study aims to address this issue by studying the performance of financial institutions in the context of Indonesia’s political, institutional and socio-cultural environment. Design/methodology/approachUsing institutional theory, the authors analyzed data collected using surveys and interviews with senior managers in Indonesian financial institutions. FindingsThe authors find that the regulative and normative elements have forced organizations to incorporate the values set by the external institutional bodies. The organizations have undertaken structural isomorphism in response to culture-cognitive elements, and differentiate themselves by focusing on the provision of quality customer service and enhanced customer satisfaction. Originality/valueThe authors provide new insights by studying how the political and institutional environment and choice of strategy influences performance of the services sector in emerging economies

A Structural Equation Model on Teacher Turn-over Intention in Relation to Organizational Commitment, School Culture and Work Environment

This quantitative study ascertained the best fit model of teacher turnover intention as predicted by organizational Commitment, school culture, and working environment.  Using complete enumeration with 400 respondents, the descriptive-causal method was applied in the study considering the employment of the Structural Equation Model.  Adapted questionnaires relative to the four variables were distributed through print and online Google Forms, which were tested for reliability using Cronbach Alpha Test.  Implementing the approved statistical tools of mean, standard deviation, Pearson Product Moment of correlation, and structural equation model, findings revealed that the evaluated schools were high in organizational commitment and teacher turnover intention and were very high in school culture and working environment.  More importantly, results indicated that organizational Commitment, school culture, and working environment had significant relationships with teacher turnover intention.  In addition, organizational Commitment and work significantly influence teacher turnover, while school culture does not have a direct influence on turnover intention.  Hence, it was concluded that organizational commitment and working environment best influence teacher turnover intention. Keywords: educational management, organizational Commitment, school culture, work environment, turnover intention, structural equation model, Philippines DOI: 10.7176/JEP/13-29-10 Publication date:October 31st 202

Solving the TTC 2011 Compiler Optimization Task with metatools

The authors' "metatools" are a collection of tools for generic programming. This includes generating Java sources from mathematically well-founded specifications, as well as the creation of strictly typed document object models for XML encoded texts. In this context, almost every computer-internal structure is treated as a "model", and every computation is a kind of model transformation. This concept differs significantly from "classical model transformation" executed by specialized tools and languages. Therefore it seemed promising to the organizers of the TTC 2011, as well as to the authors, to apply metatools to one of the challenges, namely to the "compiler optimization task". This is a report on the resulting experiences.Comment: In Proceedings TTC 2011, arXiv:1111.440

Cadmium Induced Metallothionein Synthesis in Liver of Oreochromis niloticus [Linnaeus, 1758]

Objective(s):Metallothionein (MT) are potential biomarkers that reflect the presence of heavy metals in the ecosystem/food chain.  Their synthesis has been observed to be elevated after heavy metal exposure in aquatic organisms. OREOCHROMIS NILOTICUS (O. niloticus) is a globally important aquaculture species. Hence the objective of this study was to determine the Cadmium (Cd) levels and MT induction in liver tissue of O. niloticus, to study the relationship between tissue-specific Cd accumulation and MT induction and hence correlate MTs protective role against Cadmium Method(s): Cd accumulation and MT induction levels were determined according to the methods of Ma et al., 2007. Cd concentration was determined using an Atomic Absorption Spectrophotometer (Perkin Elmer Optima-5300 DV). Findings: At specific sub lethal Cadmium exposure, w.r.t time, MT induction levels were found to be increase correspondingly to Cd levels in liver tissue. The accumulation of Cd levels in liver tissue is seen to be time and dose dependent. A positive correlation between MT induction and Cd accumulation was observed. The results suggest that MT in the liver could play a role in trapping and binding Cd and its subsequent elimination. Hence, the present investigation reveals that heavy metal induced MT levels can be considered as a biomarker for waterborne Cd contamination. A positive correlation between cadmium accumulation and MT synthesis in the liver tissue of the experimental animal is an indicator of the role of MT in heavy metal sequestration and adaptation to heavy metal contaminated ecosystems. Novelty: The results suggest that MT in the liver could play an important role by binding to Cd and its subsequent elimination. Hence, the present investigation reveals that heavy metal induced MT levels can be considered as a biomarker for waterborne Cd contamination. &nbsp