Adjectival semantics and the legal domain: A study for ontology improvement

This paper carries out a descriptive study on Portuguese adjectives. Our aim is to describe the semantics of the legal domain adjectives in order to construct an ontology which may improve Information Retrieval Systems. For this, we present an approach based on valency and semantic relations. The ontology proposed here is a first step aiming to build a legal ontology based on top-level concepts. © AEPIA.

Critical parameter determination of sonic flow controller diamond microtubes and micronozzles

In this article, the authors measure throughput of sonic diamond microtubes and micronozzles that can work as passive gas flow controllers and flow meters under choking conditions. The behavior of the outlet pressure through the microdevices using an experimental setup with constant volume and constant temperature was determined in order to obtain the critical throughput, the critical mass flow rate, and the discharge coefficients of the diamond sonic microdevices. © 2007 American Vacuum Society.

Using state-space techniques to represent frequency dependent single-phase lines directly in time domain

This paper proposes to use a state-space technique to represent a frequency dependent line for simulating electromagnetic transients directly in time domain. The distributed nature of the line is represented by a multiple 1t section network made up of the lumped parameters and the frequency dependence of the per unit longitudinal parameters is matched by using a rational function. The rational function is represented by its equivalent circuit with passive elements. This passive circuit is then inserted in each 1t circuit of the cascade that represents the line. Because the system is very sparse, it is possible to use a sparsity technique to store only nonzero elements of this matrix for saving space and running time. The model was used to simulate the energization process of a 10 km length single-phase line. ©2008 IEEE.

Multiloop controller and reference generator for a dynamic voltage restorer implementation

This paper deals with the design and analysis of a Dynamic Voltage Restorer output voltage control. Such control is based on a multiloop strategy, with an inner current PID regulator and an outer P+Resonant voltage controller. The inner regulator is applied on the output inductor current. It will be also demonstrated how the load current behavior may influence in the DVR output voltage, which justifies the need for the resonant controller. Additionally, it will be discussed the application of a modified algorithm for the identification of the DVR voltage references, which is based on a previously presented positive sequence detector. Since the studied three-phase DVR is assumed to be based on three identical H-bridge converters, all the analysis and design procedures were realized by means of single-phase equivalent circuits. The discussions and conclusions are supported by theoretical calculations, nonlinear simulations and some experimental results. ©2008 IEEE.

Utilizing cross-domain SOAP Web services using client-side languages in an enterprise mashup platform

Service oriented architectures (SOA) based on Simple Object Access Protocol (SOAP) Web services have attracted the attention of enterprises mainly for business-to-business integration and to create composite applications that execute business processes. An existing problem is the lack of preoccupation with non technical users due to the fact that to create a composite application to fulfill users needs, it is necessary to be in contact with IT staff. To overcome this issue, enterprises can take advantage of web 2.0, 'introducing in the development stage some technologies like mashups and some concepts like user empowerment, collaborative work and collective intelligence. Some results [3] [13] have shown how web 2.0 concepts can help non technical users to produce relative complex business processes. However, traditional enterprise requirements goes beyond typical web 2.0 solutions in several aspects: (1) traditional enterprise systems are based on heterogeneous stack of technologies that are not directly exploitable from a web-based client (where SOAP web services play an important role); (2) web browsers set some cross-domain security constraints making difficult to integrate services from diverse domains. In this paper, a contribution to two web 2.0 research projects [14] [15] partially solves the problems described: provide a way to invoke cross-domain backend services (based on SOAP technologies) directly only using clientside languages, without a need for any adaptation layer. © 2010 ACM.

Computational linguistic systematization of a lexicon from the ibitinga embroidery industry conceptual domain

This work discusses a proposition for organizing the lexical items from the conceptual domain labeled THE EMBROIDERY INDUSTRY OF IBITINGA in terms of a natural ontology. It also aims to establish the alignment between this ontology and the bases WordNet.Pr and WordNet.Br. © 2009 IEEE.

Representation of transmission lines in modal domain using analytical transformation matrices

The phases of a transmission line are tightly coupled due to mutual impedances and admittances of the line. One way to accomplish the calculations of currents and voltages in multi-phase lines consists in representing them in modal domain, where its n coupled phases are represented by their n propagation modes. The separation line in their modes of propagation is through the use of a modal transformation matrix whose columns are eigenvectors associated with the parameters of the line. Usually, this matrix is achieved through numerical methods which does not allow the achievement of an analytical model for line developed directly in the phases domain. This work will show the modal transformation matrix of a hypothetical two-phase obtained with numerical and analytical procedures. It will be shown currents and voltage s at terminals of the line taking into account the use of modal transformation matrices obtained by using numerical and analytical procedures. © 2011 IEEE.

Mutual coupling modeling in transmission lines directly in the phase domain

This paper describes a computational model based on lumped elements for the mutual coupling between phases in three-phase transmission lines without the explicit use of modal transformation matrices. The self and mutual parameters and the coupling between phases are modeled using modal transformation techniques. The modal representation is developed from the intrinsic consideration of the modal transformation matrix and the resulting system of time-domain differential equations is described as state equations. Thus, a detailed profile of the currents and the voltages through the line can be easily calculated using numerical or analytical integration methods. However, the original contribution of the article is the proposal of a time-domain model without the successive phase/mode transformations and a practical implementation based on conventional electrical circuits, without the use of electromagnetic theory to model the coupling between phases. © 2011 IEEE.

Resonant (P+RES) controller applied to voltage source inverter with minimum DC link capacitor

Voltage source inverters use large electrolytic capacitors in order to decouple the energy between the utility and the load, keeping the DC link voltage constant. Decreasing the capacitance reduces the distortion in the inverter input current but this also affects the load with low-order harmonics and generate disturbances at the input voltage. This paper applies the P+RES controller to solve the challenge of regulating the output current by means of controlling the magnitude of the current space vector, keeping it constant thus rejecting harmonic disturbances that would otherwise propagate to the load. This work presents a discussion of the switching and control strategy. © 2011 IEEE.

Patellofemoral pain syndrome: Electromyography in a frequency domain analysis

The Patellofemoral Pain Syndrome (PFPS), has a multifactorial etiology and affects approximately 7 to 15% of the population, mostly women, youth, adults and active persons. PFPS causes anterior or retropatelar pain that is exacerbated during functional motor gestures, such as up and down stairs or spending long periods of time sitting, squatting or kneeling. As the diagnostic evaluation of this syndrome is still indirect, different mechanisms and methodologies try to make a classification that distinguishes patients with PFPS in relation to asymptomatic. Thereby, the purpose of this investigation was to determine the characteristics of the electromyographic (EMG) signal in the frequency domain of the vastus medialis oblique (VMO) and vastus lateralis (VL) in patients with PFPS, during the ascent of stairs. 33 young women (22 control group and 11 PFPS group), were evaluated by EMG during ascent of stairs. The VMO mean power frequency (MPF) and the VL frequency 95% (F95) were lower in symptomatic individuals. This may be related to the difference in muscle recruitment strategy exerted by each muscle in the PFPS group compared to the control group.

Domain reduction using GRASP construction phase for transmission expansion planning problem

This paper proposes a new strategy to reduce the combinatorial search space of a mixed integer linear programming (MILP) problem. The construction phase of greedy randomized adaptive search procedure (GRASP-CP) is employed to reduce the domain of the integer variables of the transportation model of the transmission expansion planning (TM-TEP) problem. This problem is a MILP and very difficult to solve specially for large scale systems. The branch and bound (BB) algorithm is used to solve the problem in both full and the reduced search space. The proposed method might be useful to reduce the search space of those kinds of MILP problems that a fast heuristic algorithm is available for finding local optimal solutions. The obtained results using some real test systems show the efficiency of the proposed method. © 2012 Springer-Verlag.

A transmission line model developed directly in phase domain

The phases of a transmission line are tightly coupled due to mutual impedances and admittances of the line. One way to accomplish the calculations of currents and voltages in multi-phase lines consists in representing them in modal domain, where its n coupled phases are represented by their n propagation modes. The separation line in their modes of propagation is through the use of a modal transformation matrix whose columns are eigenvectors associated with the parameters of the line. Usually, this matrix is achieved through numerical methods which do not allow the achievement of an analytical model for line developed directly in the phases domain. This work will show an analytical model for phase currents and voltages of the line and results it will be applied to a hypothetical two-phase. It will be shown results obtained with that will be compared to results obtained using a classical model. © 2012 IEEE.

Micro-inverter for integrated grid-tie PV module using resonant controller

Two-stage isolated converters for photovoltaic (PV) applications commonly employ a high-frequency transformer on the DC-DC side, submitting the DC-AC inverter switches to high voltages and forcing the use of IGBTs instead of low-voltage and low-loss MOSFETs. This paper shows the modeling, control and simulation of a single-phase full-bridge inverter with high-frequency transformer (HFT) that can be used as part of a two-stage converter with transformerless DC-DC side or as a single-stage converter (simple DC-AC inverter) for grid-connected PV applications. The inverter is modeled in order to obtain a small-signal transfer function used to design the PResonant current control regulator. A high-frequency step-up transformer results in reduced voltage switches and better efficiency compared with converters in which the transformer is used on the DC-DC side. Simulations and experimental results with a 200 W prototype are shown. © 2012 IEEE.

Development of a simplified transmission line model directly in the phase domain

A transmission line digital model is developed direct in the phase and time domains. The successive modal transformations considered in the three-phase representation are simplified and then the proposed model can be easily applied to several operation condition based only on the previous knowing of the line parameters, without a thorough theoretical knowledge of modal analysis. The proposed model is also developed based on lumped elements, providing a complete current and voltage profile at any point of the transmission system. This model makes possible the modeling of non-linear power devices and electromagnetic phenomena along the transmission line using simple electric circuit components, representing a great advantage when compared to several models based on distributed parameters and inverse transforms. In addition, an efficient integration method is proposed to solve the system of differential equations resulted from the line modeling by lumped elements, thereby making possible simulations of transient and steady state using a wide and constant integration step. © 2012 IEEE.

The natural absence of RPA1N domain did not impair Leishmania amazonensis RPA-1 participation in DNA damage response and telomere protection.

We have previously shown that the subunit 1 of Leishmania amazonensis RPA (LaRPA-1) alone binds the G-rich telomeric strand and is structurally different from other RPA-1. It is analogous to telomere end-binding proteins described in model eukaryotes whose homologues were not identified in the protozoan's genome. Here we show that LaRPA-1 is involved with damage response and telomere protection although it lacks the RPA1N domain involved with the binding with multiple checkpoint proteins. We induced DNA double-strand breaks (DSBs) in Leishmania using phleomycin. Damage was confirmed by TUNEL-positive nuclei and triggered a G1/S cell cycle arrest that was accompanied by nuclear accumulation of LaRPA-1 and RAD51 in the S phase of hydroxyurea-synchronized parasites. DSBs also increased the levels of RAD51 in non-synchronized parasites and of LaRPA-1 and RAD51 in the S phase of synchronized cells. More LaRPA-1 appeared immunoprecipitating telomeres in vivo and associated in a complex containing RAD51, although this interaction needs more investigation. RAD51 apparently co-localized with few telomeric clusters but it did not immunoprecipitate telomeric DNA. These findings suggest that LaRPA-1 and RAD51 work together in response to DNA DSBs and at telomeres, upon damage, LaRPA-1 works probably to prevent loss of single-stranded DNA and to assume a capping function.