154 resultados para Battery chargers


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We examine the Granger causal relationship between police strength and a variety of different types of crime for South Australia. We find that with the exception of assault and homicide in the long run, the crime rate and police strength are neutral.

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This paper investigates whether low technology driver-only, battery electric commuter vehicles are feasible for New Zealand. Personal passenger transport faces several challenges in the coming decades: depletion of cheap oil reserves, increasing congestion, localised pollution, the need for reduced carbon emissions and the long term goal of sustainability. One way of solving some of these problems could be to introduce low cost, comfortable, energy efficient, driver-only electric vehicles. These would still give the driver a weatherproof, safe and comfortable means of commuting, but at a fraction of the energy and running costs of conventional petrol/diesel cars. To help assess their viability, the performance and energy use of the E-POD electric commuter vehicle is used as a benchmark. The work shows that such a vehicle could be made cheaply, using readily available technology with a range of 180km and a top speed of over 90km/h. The chassis could be made from natural fibre composite materials that might reduce significantly the embedded energy required for its manufacture. The electricity taken from the grid to charge the batteries could be replaced by electricity generated from grid connected photovoltaic panels mounted on the garage roof of the vehicle owner.

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The overall aim in this study was twofold: to compare the use of work-based (WB) and non-work-based (NWB) child care on the transition back to the workplace for women after a period of maternity leave, and on the transition into child care for the infants of these women. Thirty-five mothers with infants in WB centres and 44 mothers with infants in NWB centres completed a battery of questionnaires, retrospectively, in relation to their first four weeks of resuming work and their infant’s transition into child care. We first explored whether the mothers of infants in WB centres were less stressed and anxious
about separating from their infant, were more satisfied with their child care, and whether they felt more productive and supported at work than mothers of infants in NWB child
care centres. Our findings revealed no differences between mothers using WB centres and NWB centres in their transition to work. In exploring whether infants placed in WB centres settled faster and more easily than infants placed in NWB centres, the findings, once again, revealed no differences in the infant’s affective states at child care and maintenance of their routines, such that all infants were equally settled and happy irrespective of the type of care used. The theoretical and practical implications of our findings are discussed.

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The development and application of a novel combination of electrochemical techniques and computerized field-based battery-operated instrumentation is investigated. Low-power complementary metal oxide semiconductor technology has been utilized for the development of the field data acquisition systems and the instrumental performance of the complete analytical system is critically evaluated.

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Wood, DVD player and screen, spy-hole, 500 watt interrogation light, ergonomic interrogation chair, windscreen wiper motor and car battery 2x3x1.6m. Includes the film rendition.

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The 3rd generation partnership project (3GPP) long term evolution (LTE) standard uses single carrier frequency division multiple access (SCFDMA) scheme for the uplink transmissions and orthogonal frequency division multiplexing access (OFDMA) in downlink. SCFDMA uses DFT spreading prior to OFDMA modulation to map the signal from each user to a subset of the available subcarriers i.e., single carrier modulation. The efficiency of a power amplifier is determined by the peak to average power ratio (PAPR) of the modulated signal. In this paper, we analyze the PAPR in 3GPP LTE systems using root raised cosine based filter. Simulation results show that the SCFDMA subcarrier mapping has a significantly lower PAPR compared to OFDMA. Also comparing the three forms of SCFDMA subcarrier mapping, results show that interleave FDMA (IFDMA) subcarrier mapping with proposed root raised cosine filter reduced PAPR significantly than localized FDMA (LFDMA) and distributed (DFDMA) mapping. This improves its radio frequency (RF) power amplifier efficiency and also the mean power output from a battery driven mobile terminal.

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Fuel efficiency in a hybrid electric vehicle requires a fine balance between usage of combustion engine and battery power. Information about the geometry of the road and traffic ahead can have a great impact on optimized control and the power split between the main parts of a hybrid electric vehicle. This paper provides a survey on the existing methods of control and energy management emphasizing on those that consider the look-ahead road situation and trajectory information. Then it presents the future trends in the control and energy management of hybrid electric vehicles.

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Practical lithium-metal batteries are the ultimate goal of battery researchers. The addition of a zwitterionic compound (see Figure) to an ionic liquid electrolyte doped with a lithium salt results in a 100% enhancement of the current densities achieved in the cycling of a lithium-metal cell. This phenomenon arises due to increased lithium-ion mobility or a reduced solid electrolyte interphase layer resistance.

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To realise the battery potential of gel polyelectrolytes greater ion dissociation, ultimately leading to higher conductivities, must be achieved. Higher conductivities will result through increasing the ion-dissociating properties of the gel polyelectrolyte. The poor degree of ion dissociation arises as the active ion tends to remain in close proximity to the backbone charge. Nano-particle inorganic oxides, and zwitterionic compounds have been shown to act as dissociation enhancers in certain polyelectrolyte systems. In an attempt to further increase ion dissociation the addition of both TiO2 nano-particles and a zwitterionic compound based on 1-butylimidazolium-3-N-(butanesulphonate) were added to the gel polyelectrolyte system poly (Li-2-acrylamido-2-methyl-1-propane sulphonate-co-N,N′-dimethylacrylamide), poly(Li-AMPS-co-DMAA) to determine if a synergistic effect occurs. Two different solvents were used to determine the breadth of applicability of the additive effect. The use of both dissociators resulted in the maximum ionic conductivity being achieved at lower nano-particle concentrations when compared to an identical system without zwitterion.

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Rechargeable lithium batteries have long been considered an attractive alternative power source for a wide variety of applications. Safety and stability1 concerns associated with solvent-based electrolytes has necessitated the use of lithium intercalation materials (rather than lithium metal) as anodes, which decreases the energy storage capacity per unit mass. The use of solid lithium ion conductors - based on glasses, ceramics or polymers - as the electrolyte would potentially improve the stability of a lithium metal anode while alleviating the safety concerns. Glasses and ceramics conduct via a fast ion mechanism, in which the lithium ions move within an essentially static framework. In contrast, the motion of ions in polymer systems is similar to that in solvent-based electrolytes - motion is mediated by the dynamics of the host polymer, thereby restricting the conductivity to relatively low values. Moreover, in the polymer systems, the motion of the lithium ions provides only a small fraction of the overall conductivity2, which results in severe concentration gradients during cell operation, causing premature failure3. Here we describe a class of materials, prepared by doping lithium ions into a plastic crystalline matrix, that exhibit fast lithium ion motion due to rotational disorder and the existence of vacancies in the lattice. The combination of possible structural variations of the plastic crystal matrix and conductivities as high as 2 3 1024 S cm21 at 60 8C make these materials very attractive for secondary battery applications.

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Background: Recent work suggests that 2 biologically based traits convey risk for alcohol misuse: reward sensitivity ⁄ drive and (rash) impulsiveness. However, the cognitive mechanisms through which these traits convey risk are unclear. This study tested a model predicting that the risk conveyed by reward sensitivity is mediated by a learning bias for the reinforcing outcomes of alcohol consumption (i.e., positive alcohol expectancy). The model also proposed that the risk conveyed by rash impulsiveness (RI) is mediated by drinkers’ perceived ability to resist alcohol (i.e., drinking refusal self-efficacy).
Methods: Study 1 tested the model in a sample of young adults (n = 342). Study 2 tested the model in a sample of treatment-seeking substance abusers (n = 121). All participants completed a battery of personality, cognitive, and alcohol use questionnaires and models were tested using structural equation modeling.
Results: In both studies, the hypothesized model was found to provide a good fit to the data, and a better fit than alternative models. In both young adults and treatment-seeking individuals, positive alcohol expectancy fully mediated the association between reward sensitivity and hazardous alcohol use. For treatment seekers, drinking refusal self-efficacy fully mediated the association between RI and hazardous drinking. However, there was partial mediation in the young adult sample. Furthermore, neither trait was directly associated with the other cognitive mediator.
Conclusions: The hypothesized model was confirmed on a large sample of young adults and replicated on a sample of treatment-seeking substance abusers. Taken together, these findings shed further light on the mechanisms through which an impulsive temperament may convey risk for alcohol misuse.

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The electrochemistry of lithium is investigated in a number of electrolytes that consist of a lithium salt dissolved in a combined ionic liquid-organic diluent medium. We find that ethylene carbonate and vinylene carbonate improve electrochemical behaviour, while toluene and tetrahydrofuran are less promising.We also present insights into the electrode passivation caused by these diluents in an ionic liquid electrolyte during lithium cycling. We observe that during lithium cycling those electrolytes with carbonate based diluents are the most able to utilise their previously reported improved lithium ion diffusivities. Conversely, tetrahydrofuran, the most promising diluent of those studied in terms of its known ability to increase lithium ion diffusivity is found not to be as advantageous as a diluent. It appears that the poor electrochemical interfacial properties of the tetrahydrofuran electrolyte prevented the realisation of the benefits of the high solution lithium ion diffusivity.

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Objective: Adequate treatment of a first psychotic episode in young people is a difficult challenge but may be of critical importance for changing the course of psychotic illness. Pharmacotherapy is the standard treatment of psychosis, however there is a paucity of data specific to first-episode psychosis.
Methods: In this study 12 young people who presented with a psychotic episode at a specialised early intervention service were commenced on treatment with aripiprazole. They were assessed at baseline and weeks 4, 6, 24 and 48 using a broad battery of outcome measures. Case notes were also examined.
Results: Data was available for 6 participants at week 48, and of those, one remained on treatment with Aripiprazole at endpoint. Case histories were typified by presentations that included illicit substance use and treatments characterised by several changes in medications. No single treatment choice predominated. Most participants tolerated treatment and showed symptomatic improvement with individualised therapy.
Conclusion: Most participants showed improvement during the treatment period. Aripiprazole was one of many medications used in this study and may have been useful for the treatment of some individuals with first episode psychosis.

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It has been demonstrated that considering the knowledge of drive cycle as a priori in the PHEV control strategy can improve its performance. The concept of power cycle instead of drive cycle is introduced to consider the effect of noise factors in the prediction of future drivetrain power demand. To minimize the effect of noise factors, a practical solution for developing a power-cycle library is introduced. A control strategy is developed using the predicted power cycle which inherently improves the optimal operation of engine and consequently improves the vehicle performance. Since the control strategy is formed exclusively for each PHEV rather than a preset strategy which is designed by OEM, the effect of different environmental and geographic conditions, driver behavior, aging of battery and other components are considered for each PHEV. Simulation results show that the control strategy based on the driver library of power cycle would improve both vehicle performance and battery health.

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Using Rasch analysis, the psychometric properties of a newly developed 35-item parent-proxy instrument, the Caregiver Assessment of Movement Participation (CAMP), designed to measure movement participation problems in children with Developmental Coordination Disorder, were examined. The CAMP was administered to 465 school children aged 5–10 years. Thirty of the 35 items were retained as they had acceptable infit and outfit statistics. Item separation (7.48) and child separation (3.16) were good; moreover, the CAMP had excellent reliability (Reliability Index for item = 0.98; Person = 0.91). Principal components analysis of item residuals confirmed the unidimensionality of the instrument. Based on category probability statistics, the original five-point scale was collapsed into a four-point scale. The item threshold calibration of the CAMP with the Movement Assessment Battery for Children Test was computed. The results indicated that a CAMP total score of 75 is the optimal cut-off point for identifying children at risk of movement problems.