Quantum Singular Value Decomposer

We present a variational quantum circuit that produces the Singular Value Decomposition of a bipartite pure state. The proposed circuit, that we name Quantum Singular Value Decomposer or QSVD, is made of two unitaries respectively acting on each part of the system. The key idea of the algorithm is to train this circuit so that the final state displays exact output coincidence from both subsystems for every measurement in the computational basis. Such circuit preserves entanglement between the parties and acts as a diagonalizer that delivers the eigenvalues of the Schmidt decomposition. Our algorithm only requires measurements in one single setting, in striking contrast to the $3^n$ settings required by state tomography. Furthermore, the adjoints of the unitaries making the circuit are used to create the eigenvectors of the decomposition up to a global phase. Some further applications of QSVD are readily obtained. The proposed QSVD circuit allows to construct a SWAP between the two parties of the system without the need of any quantum gate communicating them. We also show that a circuit made with QSVD and CNOTs acts as an encoder of information of the original state onto one of its parties. This idea can be reversed and used to create random states with a precise entanglement structure.Comment: 6 + 1 pages, 5 figure

An ontology for event detection and its application in surveillance video

Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. J. C. SanMiguel, J. M. Martínez, and Á. García, "An ontology for event detection and its application in surveillance video", in Sixth IEEE International Conference on Advanced Video and Signal Based Surveillance, AVSS 2009, p. 220 - 225In this paper, we propose an ontology for representing the prior knowledge related to video event analysis. It is composed of two types of knowledge related to the application domain and the analysis system. Domain knowledge involves all the high level semantic concepts in the context of each examined domain (objects, events, context...) whilst system knowledge involves the capabilities of the analysis system (algorithms, reactions to events...). The proposed ontology has been structured in two parts: the basic ontology (composed of the basic concepts and their specializations) and the domain-specific extensions. Additionally, a video analysis framework based on the proposed ontology is defined for the analysis of different application domains showing the potential use of the proposed ontology. In order to show the real applicability of the proposed ontology, it is specialized for the underground video-surveillance domain showing some results that demonstrate the usability and effectiveness of the proposed ontology.This work is partially supported by the Spanish Administration agency CDTI (CENIT-VISION 2007-1007), by the Spanish Government (TEC2007- 65400 SemanticVideo), by the Comunidad de Madrid (S-050/TIC- 0223 - ProMultiDis), by the Consejería de Educación of the Comunidad de Madrid and by The European Social Fun

Hope for the best and prepare for the worst. Do short-time work schemes help workers remain in the same firm?

Purpose &- This paper investigates whether short-time work (STW) schemes were successful in their objectiveof maintaining employment and keeping workers employed within the same firms after the onset of thefinancial and economic crisis in 2008.Design/methodology/approach &- Spanish longitudinal administrative data has been used, making itpossible to identify short-time work (STW) participation not only of workers but also of employers andallowing to know the future labour market status of participants and non-participants. Accordingly, treatmentand control groups are defined, and Propensity Score Matching models estimated. The dependent variable ismeasured as the probability that an individual remained employed with the same employer in the future (one,two and three years) after implementation of a STW arrangement.Findings &- Our results suggest that treated individuals are about 5 percentage points less likely to remainworking with the same employer one year later than similar workers, and this negative effect of participationincreases over time. Thus, STW schemes would not have the assumed effect of preventing unemployment bykeeping the participants employed relative to non-participants.Research limitations/implications &- As our analysis is based on the comparison of the employmenttrajectories of participant and non-participant workers in firms that have used STW arrangements, ourfindings cannot be interpreted as the job saving effects of either macro or micro studies carried out previously.Practical implications &- The analysis carried out in the paper is complementary to the country-level andfirm-level approaches that have been used in the empirical literature.Originality/value &- We adopt a worker-level approach. This is novel since no previous study has focusedattention on the impact of STW participation on the subsequent labour market status of workers

Short-time work and employment stability: Evidence from a policy change

This paper investigates whether short-time work (STW) programmes achieve their stated goal of being devices intended to preserve jobs and keep workers employed in times of crisis. Our identification strategy exploits a change in the financial incentives provided to employers and employees for the temporary suspension of work contracts or the reduction of working time. We use longitudinal administrative data and estimate difference-in-differences regressions and instrumental variable bivariate probit models with endogenous covariates, which try to take account of the potential endogeneity of participation in STW. Our results suggest that discretionary policy changes in the incentives of STW schemes can be effective in the short run but they lose their ability when the decline in demand and the lack of work are more permanent

Job quality differences among younger and older workers in Europe: The role of institutions

We compare non-wage aspects of job quality of younger and older workers across European countries and relate the differences between them to the prevailing institutional settings. Microdata from the European Union Labour Force Survey are used to carry out the measurement of a job quality index during the period 2005–2015, while aggregate indicators are used to approximate a set of labour market institutions. Our findings support the notion that the institutional framework affects the age gap in job quality. Among other results, we find that older workers fare better than younger workers, that the employment quality is higher for employees working in countries where the wage-bargaining system is more coordinated/centralized and the employment protection for regular workers is stricter and that these institutions tend to favour the job quality of older workers over younger ones

Space Vector Modulation Techniques for Multilevel Converters – a survey

This paper presents a survey of most recent, simple and efficient Space Vector Modulation algorithms for multilevel converters. These algorithms avoid trigonometric and other complex operations, leading to more simple and cost efficient implementations. They can be applied to multilevel topologies and present freedom degrees that can be Exploited in order to optimize system parameters in the system like: capacitors voltages balancing or voltage/current ripples. Experimental results are presented to show the good performance of the algorithms

Fracture test of a Gothic ribbed vault

A Gothic ribbed vault has been built at the School of Architecture of Madrid in order to investigate the construction complexities of this kind of vaults. The ribbed vault is described in the manuscript of Alonso de Vandelvira, and its shape was reconstructed making using the drawings this architect from the 16th century. The fracture test was carried on by loading the central keystone of the vault until its collapse took place. The experiment was filmed and by doing so, it was possible to observe the failure mechanism of the vault. At the same time, it was interesting to compare this collapse experience with the results obtained using two different me-thods. First, a stability calculation was carried out through graphic statics, and secondly a calcu-lation was performed using the rigid-block analysis method. The focus of this paper is to show and analyze the results of both studies

How do we pursue labormetrics? An application using the MCVL

The authors wish to thank the Spanish Social Security for providing the data for this research. Carlos García-Serrano acknowledges financial support by the Ministry of Science and Innovation (National Plan, ECO2010-19963) while José M. Arranz and Virginia Hernanz by the Ramón Areces Foundation. Thanks are also extended to an anonymous referee for helpful comments.The objective of this paper is to describe a process through which the original information of an administrative data source (the Spanish “Continuous Sample of Working Life” -“Muestra Continua de Vidas Laborales”) can be organised in such a way as to permit the accurate study of work histories. It presents a comparison of the information obtained using the procedure we propose by linking the available samples (2004-2010 complete cumulative spells file) and that obtained using retrospectively only one sample (2010 data file) in three empirical applications. The aim of these applications is to demonstrate the sample loss and the potential biases which occur when data on spells and individuals are not processed correctly

How do we pursue labormetrics? An application using the MCVL

The authors wish to thank the Spanish Social Security for providing the data for this research. Carlos García-Serrano acknowledges financial support by the Ministry of Science and Innovation (National Plan, ECO2010-19963) while José M. Arranz and Virginia Hernanz by the Ramón Areces Foundation. Thanks are also extended to an anonymous referee for helpful comments.The objective of this paper is to describe a process through which the original information of an administrative data source (the Spanish “Continuous Sample of Working Life” -“Muestra Continua de Vidas Laborales”) can be organised in such a way as to permit the accurate study of work histories. It presents a comparison of the information obtained using the procedure we propose by linking the available samples (2004-2010 complete cumulative spells file) and that obtained using retrospectively only one sample (2010 data file) in three empirical applications. The aim of these applications is to demonstrate the sample loss and the potential biases which occur when data on spells and individuals are not processed correctly

The changing use of short-time work schemes: Evidence from two recessions

We explore differences in resort to short-time work schemes between the recessions in the early 1990s and the late 2000s in Spain and Italy and explore how far these are associated with differences in employees" personal and job-related characteristics. We use individual data from national Labour Force Surveys and perform a multivariate detailed decomposition. We find that participation in these schemes in the second recession would have been even greater without the changes in skills and production structures in both countrie