Search results for "push"

High-Efficiency Regulation Method for a Zero-Current and Zero-Voltage Current-Fed Push–Pull Converter

2011

A new high-efficiency regulation method for a zero-current and zero-voltage current-fed push-pull converter is presented. The method proposed is based on the use of a controlled transformer as a post-regulator, which adds or subtracts an additional voltage to the output filter of the converter. An auxiliary regulator, which only handles a percentage of the output power, controls this transformer, and therefore, results in much higher efficiency than a normal preregulator would have. The novelty of the presented converter is that regulation is achieved without affecting the zero-voltage and zero-current switching in any working conditions. Small- and large-signal models of the converter have…

Harmonicity and minimality of oriented distributions

2004

We consider an oriented distribution as a section of the corresponding Grassmann bundle and, by computing the tension of this map for conveniently chosen metrics, we obtain the conditions which the distribution must satisfy in order to be critical for the functionals related to the volume or the energy of the map. We show that the three-dimensional distribution ofS4m+3 tangent to the quaternionic Hopf fibration defines a harmonic map and a minimal immersion and we extend these results to more general situations coming from 3-Sasakian and quaternionic geometry.

Physical Fitness and Body Anthropometrics Profiles of the Female Recruits Entering to Voluntary Military Service.

2018

An in vitro comparison of different adhesive strategies on the micro push-out bond strength of a glass fiber post

2010

Objectives: To evaluate in vitro the push-out bond strengths of a glass fiber post adhesively luted with self-etching resin based and self-adhesive luting cements, as well as modified application procedure of self-adhesive luting cements in combination with single step self-etch adhesives. Materials and methods: Fifty single-rooted human maxillary central incisor teeth were endodontically treated and divided into five groups (n=10). Glass fiber posts (RelyX Fiber Post) were cemented with the following materials: group 1: ED Primer II/Panavia F 2.0 (PAN); group 2: RelyX Unicem (RU); group 3: Maxcem (MC); group 4: Adper Prompt L-Pop (PLP)/RelyX Unicem; group 5: Optibond all-in-one (OB)/Maxcem…

Social factors as the catalyst of emigration

2022

The objective of the study is to address the factors contributing to emigration from Latvia, in particular by highlighting the importance of social factors in the emigration decision, using the theory of push and pull factors of migration as a theoretical basis. The role of the family and the desire to improve not only the economical, but also the social and psychological conditions of families are important factors in the decision-making process, while maintaining links with Latvia. The authors argue that social factors are essential to the migration decision alongside economic factors, and in particular the family situation. The family is a resource that helps to settle in the new country…

Influence of column shear failure on pushover based assessment of masonry infilled reinforced concrete framed structures: A case study

2017

Structural frames, constructed either of steel or reinforced concrete (RC), are often infilled with masonry panels. However, during the analysis of the structural frames, it has become common practice to disregard the existence of infills because of the complexity in modeling. This omission should not be allowed because the two contributions (of infills and of frames) complement each other in providing a so different structural system. The use of different modeling assumptions significantly affects the capacity as well as the inelastic demand and safety assessment. In specific, the adoption of equivalent diagonal pin-jointed struts leaves open the problem of the evaluation of the additional…

Non linear and linearized combination coefficients for modal pushover analysis

2017

Current design practice and seismic codes tend to assess seismic demand of buildings by Non linear Static Analysis (NSA), based on the evaluation of the pushover curve. Earlier non-linear static analysis procedure estimate the response peak value by evaluating the push-over curve adopting a distribution of invariant forces proportional to the fundamental vibration mode. In order to include the effect of higher modes several multimodal push-over analysis procedures were proposed in literature. In In the most famous of these, namely Modal Pushover Analysis (MPA), nodal response peak values are obtained by combination of "modal" responses by the traditional SRSS or CQC methods: the use of the …

Muscle Activity During Unilateral vs. Bilateral Battle Rope Exercises.

2015

High training intensity is important for efficient strength gains. Although battle rope training is metabolically demanding, no studies have quantified intensity of muscle activity during this type of training. This study analyzes muscle activity during unilateral alternating waves vs. bilateral waves of battle rope training. Twenty-one volunteers participated in a repeated-measures study on 2 different occasions. Surface electromyographic signals were recorded from the anterior deltoid (AD), external oblique (OBLIQ), lumbar erector spinae (LUMB), and gluteus medius (GM) during bilateral waves and unilateral waves and were normalized to the maximum voluntary isometric contraction (MVIC). Re…

Dentin wettability enhancement for three irrigating solutions and their effect on push out bond strength of gutta percha / AH Plus

2014

Background: The aim of this study was to investigate the effect of wettability enhancement for 17% EDTA, 2.5% sodium hypochlorite and 7% maleic acid solutions on push out bond strength of gutta percha /AH Plus to root dentin. Materials and Methods: One hundred and eight extracted single rooted human lower premolars were instrumented up to Protaper Universal F5 then irrigated with 3ml of 2.5% NaOCl after each file. Irrigants were prepared and a pilot study for determination of Tween 80 concentration yielding the lowest surface tension value in every solution was conducted. Samples were randomly divided into a control group and two experimental groups (17% EDTA and 7% Maleate), further split …

Competitive (versus Loyal) Showrooming: An Application of the Push-Pull-Mooring Framework

2021

Abstract Showrooming is an increasingly popular practic that threatens retailers' performance. This paper adopts the push-pull-mooring framework to understand the shopper decision to purchase online from a different retailer (competitive showrooming) rather than from the same retailer visited to gather information (loyal showrooming). Going beyond the customer motivation to get the best value, we focus on retailer-situational variables (store crowding and quality of salesperson service) and retailer-relational variables (customer satisfaction, trust and loyalty) in the decision on competitive (vs loyal) showrooming. Data was collected via a survey answered by 659 showroomers and analysed us…