1,340 research outputs found

    MICROCONTROLLER BASED AUTOMATIC CONTROL FOR WATER PUMPING MACHINE WITH WATER LEVEL INDICATORS USING ULTRASONIC SENSOR

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    Water scarcity is one of the major problems facing some cities of the world and wastage during transmission has been identified as a major problem. In this paper a Microcontroller Based Automatic Control for Water Pumping Machine and Level Indicator (MBACWPMLI) has been designed, constructed and tested. The MBACWPML I uses the reflection of sound (echo) to give the indication of water level in a storage tank and also the automatic control of the water pumping machine. The MBACWPMLI uses ultrasonic sensor installed at the top of a tank to send and receive sound waves, and the time taken is converted to distance by the microcontroller to give corresponding digital outputs which turns ON LEDs that indicate the level of water in the storage tank. The microcontroller also gives digital output to turn ON the water pump (when the water in the tank is at a preset minimum level of 0.27 metres) or turn OFF the water pump (when the water goes above the chosen maximum level of 0.05 metres). The MBACWPMLI when tested turned ON or OFF the water pump at the preset minimum and maximum level and the required LEDs were also turned ON at the corresponding water level.  http://dx.doi.org/10.4314/njt.v35i3.1

    A double-track greedy channel routing algorithm

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    A New Optimization Cost Model for VLSI Standard Cell Placement

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    In this paper, we propose a new optimization cost model for VLSI placement. It distinguishes itself from the traditional wire-length cost model by having direct impact on the quality of the detailed routing phase. We also extend the well-known simulated annealing standard cell placement algorithm by applying our new cost model. Experimental results show that we got 13% layout area reduction compared to traditional wire length model, 11% reduction to commercial tool.published_or_final_versio

    Investigation of Possible Antidotal Effects of Activated Charcoal, Sodium Bicarbonate, Hydrogen Peroxide and Potassium Permanganate in Zinc Phosphide Poisoning

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    Zinc phosphide, a commonly used rat poison in Kenya was mixed with maize flour in a concentration of 0.15 % w/w and fed to a group of 60 experimental mice for 3 hours. The mice were then randomly divided into 5 equal groups, A, B, C, D and E. To group A, B, C and D was administered 1 ml of activated charcoal (3 % w/v), sodium bicarbonate (10 % w/v), hydrogen peroxide (0.5 % v/v) and potassium permanganate (1:5000), respectively. Group E was given 1 ml distilled water and used as control. All five groups were observed for symptoms of toxicity, often culminating in death. The observations were continued over a period of 36 hours. Results of the experiment showed that all 4 test substances minimized the lethal effect of zinc phosphide. Although no attempt was made to quantify the antidotal effect of the 4 substances, activated charcoal appeared to have a higher effect than the others, while potassium permanganate had a low rating. Key Words: Zinc phosphide, rat poison, antidote East and Central African Journal of Pharmaceutical Sciences Vol.5(2) 2002: 38-4

    High efficiency silicon solar cell based on asymmetric nanowire

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    Improving the efficiency of solar cells through novel materials and devices is critical to realize the full potential of solar energy to meet the growing worldwide energy demands. We present here a highly efficient radial p-n junction silicon solar cell using an asymmetric nanowire structure with a shorter bottom core diameter than at the top. A maximum short circuit current density of 27.5 mA/ cm(2) and an efficiency of 7.53% were realized without anti-reflection coating. Changing the silicon nanowire (SiNW) structure from conventional symmetric to asymmetric nature improves the efficiency due to increased short circuit current density. From numerical simulation and measurement of the optical characteristics, the total reflection on the sidewalls is seen to increase the light trapping path and charge carrier generation in the radial junction of the asymmetric SiNW, yielding high external quantum efficiency and short circuit current density. The proposed asymmetric structure has great potential to effectively improve the efficiency of the SiNW solar cells.111918Ysciescopu

    Developing an EEG-based on-line closed-loop lapse detection and mitigation system

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    © 2014 Wang, Huang, Wei, Huang, Ko, Lin, Cheng and Jung. In America, 60% of adults reported that they have driven a motor vehicle while feeling drowsy, and at least 15-20% of fatal car accidents are fatigue-related. This study translates previous laboratory-oriented neurophysiological research to design, develop, and test an On-line Closed-loop Lapse Detection and Mitigation (OCLDM) System featuring a mobile wireless dry-sensor EEG headgear and a cell-phone based real-time EEG processing platform. Eleven subjects participated in an event-related lane-keeping task, in which they were instructed to manipulate a randomly deviated, fixed-speed cruising car on a 4-lane highway. This was simulated in a 1st person view with an 8-screen and 8-projector immersive virtual-reality environment. When the subjects experienced lapses or failed to respond to events during the experiment, auditory warning was delivered to rectify the performance decrements. However, the arousing auditory signals were not always effective. The EEG spectra exhibited statistically significant differences between effective and ineffective arousing signals, suggesting that EEG spectra could be used as a countermeasure of the efficacy of arousing signals. In this on-line pilot study, the proposed OCLDM System was able to continuously detect EEG signatures of fatigue, deliver arousing warning to subjects suffering momentary cognitive lapses, and assess the efficacy of the warning in near real-time to rectify cognitive lapses. The on-line testing results of the OCLDM System validated the efficacy of the arousing signals in improving subjects' response times to the subsequent lane-departure events. This study may lead to a practical on-line lapse detection and mitigation system in real-world environments

    Using Latent Class Analyses to Examine Health Disparities among Young Children in Socially Disadvantaged Families during the COVID-19 Pandemic

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    Rising income inequality is strongly linked to health disparities, particularly in regions where uneven distribution of wealth and income has long been a concern. Despite emerging evidence of COVID-19-related health inequalities for adults, limited evidence is available for children and their parents. This study aimed to explore subtypes of families of preschoolers living in the disadvantaged neighborhoods of Hong Kong based on patterns of family hardship and to compare their patterns of parenting behavior, lifestyle practices, and wellbeing during the COVID-19 pandemic. Data were collected from 1338 preschoolers and their parents during March to June 2020. Latent class analysis was performed based on 11 socioeconomic and disease indicators. Multivariate logistic regressions were used to examine associations between identified classes and variables of interest during the COVID-19 pandemic. Four classes of family hardship were identified. Class 1 (45.7%) had the lowest disease and financial burden. Class 2 (14.0%) had the highest financial burden. Class 3 (5.9%) had the highest disease burden. Class 4 (34.5%) had low family income but did not receive government welfare assistance. Class 1 (low hardship) had lower risks of child maltreatment and adjustment problems than Class 2 (poverty) and Class 3 (poor health). However, children in Class 1 (low hardship) had higher odds of suffering psychological aggression and poorer physical wellbeing than those in Class 4 (low income), even after adjusting for child age and gender. The findings emphasize the need to adopt flexible intervention strategies in the time of large disease outbreak to address diverse problems and concerns among socially disadvantaged families

    Sensory Electrical Stimulation Improves Foot Placement during Targeted Stepping Post-Stroke

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    Proper foot placement is vital for maintaining balance during walking, requiring the integration of multiple sensory signals with motor commands. Disruption of brain structures post-stroke likely alters the processing of sensory information by motor centers, interfering with precision control of foot placement and walking function for stroke survivors. In this study, we examined whether somatosensory stimulation, which improves functional movements of the paretic hand, could be used to improve foot placement of the paretic limb. Foot placement was evaluated before, during, and after application of somatosensory electrical stimulation to the paretic foot during a targeted stepping task. Starting from standing, twelve chronic stroke participants initiated movement with the non-paretic limb and stepped to one of five target locations projected onto the floor with distances normalized to the paretic stride length. Targeting error and lower extremity kinematics were used to assess changes in foot placement and limb control due to somatosensory stimulation. Significant reductions in placement error in the medial–lateral direction (p = 0.008) were observed during the stimulation and post-stimulation blocks. Seven participants, presenting with a hip circumduction walking pattern, had reductions (p = 0.008) in the magnitude and duration of hip abduction during swing with somatosensory stimulation. Reductions in circumduction correlated with both functional and clinical measures, with larger improvements observed in participants with greater impairment. The results of this study suggest that somatosensory stimulation of the paretic foot applied during movement can improve the precision control of foot placement

    Evidence of individual differences in the long-term social, psychological, and cognitive consequences of child maltreatment

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    Background: The prevalence and consequences of child maltreatment are alarming, but evidence from studies with long follow-up intervals are limited. This study examined the long-term consequences of child maltreatment in relation to age of onset and follow-up interval. / Methods: The exposed group comprised 63 individuals (aged 13–34 years) with a first-time diagnosis of child maltreatment between 2001 and 2010, whereas the unexposed group comprised 63 individuals who were matched upon gender, age of onset, follow-up period, and poverty status at the index hospital admission but had no medical records of maltreatment in Hong Kong. The participants completed a set of questionnaires on executive functions and mental health and provided blood samples for measurement of IL-6 and IL-10 levels during a health assessment session. / Results: Compared with the unexposed group, the exposed group reported poorer maternal care during childhood (β = −4.64, p < 0.001) and had lower family support (β = −2.97, p = 0.010) and higher inflammatory responses (IL-6: β = 0.15, p = 0.001; IL-10: β = 0.11, p = 0.011) at follow-up. Additionally, the associations of childhood maltreatment exposure with family support and maternal care differed by age of onset and the length of time since exposure. / Conclusions: This matched cohort study highlights childhood maltreatment as a risk factor for systemic inflammation and an indicator of suboptimal social environment, both of which could persist over a long period of time
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