Paviršinių mikrodefektų lokalizavimo galimybių tyrimas

Analysis of linear spatial resolution of vibrating Kelvin–Zisman electrode is carried out in case when the size of defective area is substantially less than diameter of vibrating probe. Dependence of relative error of voltage determination and defective area center’s coordinate determination on scanning speed was examined and influence of measuring device pass band was estimated also. Analysis of theoretical results and carried out experiments on real samples and its models allows us to state that contactless capacitic electric potential measuring devices operating on principle of vibrating Kelvin Zisman probe allows to localize single microdefects and its groups when their dimensions are less the diameter of vibrating probe, approximately measure surface electric potential and electron work function of these microdefective areas

Paviršinių mikrodefektų lokalizavimo galimybių tyrimas

Analysis of linear spatial resolution of vibrating Kelvin–Zisman electrode is carried out in case when the size of defective area is substantially less than diameter of vibrating probe. Dependence of relative error of voltage determination and defective area center’s coordinate determination on scanning speed was examined and influence of measuring device pass band was estimated also. Analysis of theoretical results and carried out experiments on real samples and its models allows us to state that contactless capacitic electric potential measuring devices operating on principle of vibrating Kelvin Zisman probe allows to localize single microdefects and its groups when their dimensions are less the diameter of vibrating probe, approximately measure surface electric potential and electron work function of these microdefective areas

Didelės spartos talpos ir įtampos keitiklis

Theoretical analysis and experimental investigation of the method to measure capacitance and structure’s capacitance-voltage characteristics by means of linearly varying voltage showed a linear dependence between the output voltage and capacitance (when transient process is over). Whereas the duration of transient process is determined mainly by the value of measured capacitance multiplied by resistance, the transient duration may be reduced by lowering resistor’s value, though it decreases signal to noise ratio. We choose another solution – the compensation of electric capacitance, which very effectively reduces (by a factor of several tens) the transient duration and does not affect the relationship measured capacitance – output voltage. It increases the operation speed of capacitance-voltage converter

Didelės spartos talpos ir įtampos keitiklis

Theoretical analysis and experimental investigation of the method to measure capacitance and structure’s capacitance-voltage characteristics by means of linearly varying voltage showed a linear dependence between the output voltage and capacitance (when transient process is over). Whereas the duration of transient process is determined mainly by the value of measured capacitance multiplied by resistance, the transient duration may be reduced by lowering resistor’s value, though it decreases signal to noise ratio. We choose another solution – the compensation of electric capacitance, which very effectively reduces (by a factor of several tens) the transient duration and does not affect the relationship measured capacitance – output voltage. It increases the operation speed of capacitance-voltage converter

The effect of block and traditional periodization training models on jump and sprint performance in collegiate basketball players

Scanlan, AT ORCiD: 0000-0002-0750-8697This study investigated the effect of block periodization (BP) and traditional periodization (TP) approaches on jumping and sprinting performance in collegiate basketball players during an 8-week pre-season period. Ten collegiate male basketball players (mean±SD; age: 21.5±1.7 years; body mass: 83.5±8.9 kg; stature: 192.5±5.4 cm) from the same team were equally assigned to a training group (BP or TP). BP and TP were designed with different numbers of power sessions (BP=8; TP=16) and recovery days (BP=14; TP=8). Counter-movement jump (CMJ) and 20-m sprint performance was measured prior to training commencement (baseline) and every 2 weeks thereafter (week 2, week 4, week 6 and week 8). Within-group, between-group and individual changes were assessed using magnitude-based statistics. Substantially higher (likely positive) CMJ scores were evident in week 8 compared to baseline, week 2 and week 4 with BP training. Substantially higher CMJ values were only observed in week 2 (likely positive) compared to baseline, with TP training. Sprint data showed likely negative differences in week 6 compared to baseline in both TP and BP, with no substantial differences in week 8. The only performance difference between TP and BP training was in CMJ in week 8 (very likely negative). Individual analysis showed that only three athletes demonstrated a negative predicted score (i.e. lower sprinting time) in BP, while all players following the TP model demonstrated positive predicted scores. BP training showed substantially higher jumping performance compared to TP, while no improvement in sprinting performance was observed in either training approach. Basketball coaches should consider using BP training rather than TP to train players' jumping abilities. © 2018 Institute of Sport. All rights reserved

Characterisation of semiconductor materials for ionising radiation detectors

Methods for the detection and characterisation of semiconductor material parameters and inhomogeneities are analysed. The peculiarities of different "classical" material and structure characterisation methods are discussed. The methods of lifetime and surface recombination mapping and electric field distribution in the samples are presented. Some results of investigations of GaAs, Si and SiC are used for the characterisation of different peculiarities or methods

The effect of block and traditional periodization training models on jump and sprint performance in collegiate basketball players

This study investigated the effect of block periodization (BP) and traditional periodization (TP) approaches on jumping and sprinting performance in collegiate basketball players during an 8-week pre-season period. Ten collegiate male basketball players (mean±SD; age: 21.5±1.7 years; body mass: 83.5±8.9 kg; stature: 192.5±5.4 cm) from the same team were equally assigned to a training group (BP or TP). BP and TP were designed with different numbers of power sessions (BP=8; TP=16) and recovery days (BP=14; TP=8). Counter-movement jump (CMJ) and 20-m sprint performance was measured prior to training commencement (baseline) and every 2 weeks thereafter (week 2, week 4, week 6 and week 8). Within-group, between-group and individual changes were assessed using magnitude-based statistics. Substantially higher (likely positive) CMJ scores were evident in week 8 compared to baseline, week 2 and week 4 with BP training. Substantially higher CMJ values were only observed in week 2 (likely positive) compared to baseline, with TP training. Sprint data showed likely negative differences in week 6 compared to baseline in both TP and BP, with no substantial differences in week 8. The only performance difference between TP and BP training was in CMJ in week 8 (very likely negative). Individual analysis showed that only three athletes demonstrated a negative predicted score (i.e. lower sprinting time) in BP, while all players following the TP model demonstrated positive predicted scores. BP training showed substantially higher jumping performance compared to TP, while no improvement in sprinting performance was observed in either training approach. Basketball coaches should consider using BP training rather than TP to train players' jumping abilities. © 2018 Institute of Sport. All rights reserved