batterydata/paper-abstracts huggingface dataset:
This paper presents the techno-economic design and analysis of a nanogrid system for five neighboring houses, using an energy-poor village in Gwagwalada-Abuja, Nigeria as a case study. It explores the possibility of different energy configurations – solar nanogrid (SNg), solar/wind nanogrid (SWNg), solar/diesel nanogrid (SDNg), solar/wind/diesel nanogrid (SWDNg) and diesel nanogrid (DNg) systems. The study uses the demand patterns obtained during a field survey to determine the aggregate load profile and the energy generation systems. It presents detailed capacities, annual energy, losses, battery state of charge (SoC), unmet demand, loss of load probability (LOLP), availability and the demand growth analyses. Results reveal that 5–14.5kW SNg can meet the users’ demand of∼12.5–36.5kWh/d achieving an availability of 99.2–99.6%. However, an availability of 100% was obtained for the hybrid options, including the DNg. These are 2.5–7kW PV and a 1.8–3.6kW wind generator; 5kW PV and 5kW diesel systems; 2.5PV, 1.8kW wind and 5kW diesel system; 2.5–5kW diesel generator systems. The results also demonstrate that the hybrid nanogrids achieves better battery profiles compared to the single-source option because of their complementary characteristics; thus, satisfying the battery constraint of SoC≥30% during the year. The initial cost of the DNg option is ∼6–22% of those of the renewable energy-based nanogrids. The study further reveals that nanogrids with diesel generators have relatively higher life cycle costs because of the fuel costs. Though renewable energy-based nanogrids have relatively higher initial capital costs, their life cycle costs are lower than those of the DNg. The research can be used for planning new electrification systems for rural communities around the globe.
The successful phase separation of P2- and O3-phase Na2/3Fe1/2Mn1/2O2 is demonstrated using co-precipitation method. Although P2-phase displays superior thermodynamic stability at 2/3Na and 1/2Fe:1/2Mn concentration, O3-phase can be stabilized by the means of kinetic control. The electrochemical performance evaluation with half- and full-cells prove that P2- and O3-phase exhibit comparable overall electrochemical performances when the concentrations of Na+ and transition metal constituents in the pristine state are the same. In fact, O3-phase exhibits a slightly larger reversible capacity while P2-phase exhibits slightly better average Coulombic efficiency and polarization under the same electrochemical testing conditions. Electrochemical impedance spectroscopy is used for an in-depth analysis of charge transfer rate and conductivity. The ex situ XRD experiments of both electrodes at 25th cycle show that the pristine crystal structure is maintained under the experimental conditions which indicates the structural stabilities of both electrodes although the gradual capacity degradation is observed due to the complex reactions during the cycling.
Surface modification of LiNi0.4Mn0.4Co0.2O2 (442) compound with certain metal oxides viz., Al2O3, Bi2O3 and In2O3 has been attempted with a view to improve the structural and cycling stability, especially upon high voltage and high rate cycling conditions. In addition to HF scavenging effect, the protective metal oxide inter-connect layer restricts the number of oxide ion vacancies eliminated during the initial cycling of cathode, resulting in the reduced irreversible capacity loss of the first cycle. Among the surface modified cathodes, Bi2O3 coated LiNi0.4Mn0.4Co0.2O2 cathode exhibits appreciable specific capacity values of 196mAhg−1 (Q dc1) and 175mAhg−1 (Q dc100) with 89% capacity retention, thus evidencing the superiority of Bi2O3 modifier in improving the electrochemical behavior of pristine LiNi0.4Mn0.4Co0.2O2 cathode. Further, suitability of Bi2O3 coated LiNi0.4Mn0.4Co0.2O2 cathode for high voltage (5.0V) and high rate (3C) lithium intercalation and de-intercalation applications has been demonstrated up to 100 cycles. Based on the extent of improvement in electrochemical behavior, the cathodes under investigation could be arranged in the order: Bi2O3 coated>Al2O3 coated>In2O3 coated>uncoated LiNi0.4Mn0.4Co0.2O2 oxide.
Tavorite-structured lithium-metal-fluorophosphates for Li+ transition have been recognized as a good alternative to olivine-type cathodes for lithium-ion batteries. They show an exceptional ionic conductivity, excellent thermal stability and capacity retention. In this work, LiFePO4F with high purity is successfully synthesized by a two-step solid-state route. Rietveld refinement shows that open pathways for 3D ion transport exist in LiFePO4F and its discharged state (Li2FePO4F). Cyclic voltammetry data exhibit a clear indication of the Fe3+/2+ redox couple that involves a two-phase transition. Galvanostatic discharge-charge cycling was examined at the rates 0.1 - 5C up to 1000 cycles. The voltage plateaus on 2.71 / 2.86V indicate a low electrode polarization of 0.15V. This work attained the largest initial discharge capacity at the highest rate (1C) reported to date, and almost the same capacity retention at a tenfold higher rate (1C) than that (0.1C) within the maximum cycles of 100 reported to date.
Polymers are increasingly being used in implantable biomedical applications owing to their flexibility and compatibility with micro-fabrication processes. A liquid crystal polymer (LCP) is an inert, highly water-resistant polymer that is suitable for the encapsulation of electronic components and as a substrate material for fabricating neural interfaces. Therefore, the monolithic integration of a neural interface and electronics packaging is enabled by the use of an LCP, which has salient benefits in terms of performance and reliability. For these reasons, LCPs have been studied extensively as a base material for neural prosthetic devices. In this paper, we review recently developed enabling technologies, and demonstrate prototype devices and their performance capabilities. Lifetime estimations and technical challenges of LCP-based neural prosthetic devices are also described.
Wireless Sensor Network (WSN) is a self-organized network, contains sensor nodes deployed in particular regions to gather the environmental parameters and communicate the information to the base station directly through intermediate nodes. In recent times, WSN has gained attention from wireless device manufacturers, researchers, and users for remotely accessing and monitoring the information in diverse environments. The scalability and routing are the major concerns of the network. Apart from that, the performance of WSN depends on network simulation parameters such as delay, throughput, packet delivery ratio (PDR), and control overhead. The research paper focused on the DSDV and OLSR routing protocol realization on the new hardware platform. The hardware chip of these protocols is designed in Xilinx ISE 14.7 software using VHDL, targeted on Virtex-5 FPGA. The node communication is verified on Modelsim 10.0 simulation software. The FPGA hardware and timing parameters are analyzed for different node clusters (N = 10, 20 …150) configuration. The OLSR routing protocol network performance parameters are used to build the machine learning prediction model using cluster tree regression, random forest regression, multiple regression, and K-means clustering. The K-means clustering predicted 99.12% and 98.50% accuracy in terms of the packet delivery ratio and throughput respectively.
This study examines the effects of takeover defenses on the value implication of dividends. Using the framework of Fama and French in J Finance 53(3): 819–843 (1998), the paper shows that dividends paid by managers with strong managerial power resulting from takeover protection measures are more valued in the stock market. The results are consistent with the hypothesis of the agency costs of free cash flow built on by Jensen in Am Econ Rev 76(2): 323–329 (1986) in the sense that dividends are important to determine firm value by reducing the free cash flow that would otherwise be deployed for private benefits by entrenched managers. This paper also examines whether the incremental value effect of dividends in entrenched firms is attributable to a numerator effect (changes in the future cash flow) or a denominator effect (changes in the discount rate). The empirical results show that the dividend payout of such firms is more positively related to future performance and more negatively related to information risk, which supports both numerator and denominator effects.
It's desirable to design an ideal three-dimensional (3D) interpenetrating network as the current collector for providing efficient ion and electron transport. Herein, we report a facile method to fabricate a novel continuous 3D Ni porous nanoarchitecture via the reduction of Ni(OH)2 nanowall precursors. The as-formed continuous 3D Ni porous network as the conductive scaffold can support a highly electrolytic accessible surface area of redox active MnO2 nanosheets, and provide reliable electrical connections to the MnO2 layers. In comparison with the planar conducting substrates, this 3D scaffold not only can increase the mass loading of MnO2 active materials, but also facilitate the facile transport of electron and electrolyte ion. Thus, the 3D (MnO2/Ni) electrode exhibited higher specific capacitance (1169.6 F g−1 at 2 A g−1, closed to the theoretical value) and better long-term cyclability (only ∼5% loss after 1000 cycles) than that on the planar conducting substrate under the identical electrodeposition condition (611.6 F g−1 at 2 A g−1 and around 20% loss after 1000 cycles). These results suggest that such 3D Ni porous architecture is a promising current collector for high-performance electrochemical capacitor.
In this study, α-Fe2O3 nanorings@reduced graphene oxide (α-Fe2O3@rGO) composites have been prepared through a facile hydrothermal self-assembly process. This strategy achieved the effective reduction of graphene oxide (GO) to graphene as well as the homogenous distribution of α-Fe2O3 nanorings on the surface of crumpled graphene nanosheets. The α-Fe2O3@rGO composites exhibit a much higher specific capacity of 781mAhg−1 after 100cycles at the current density of 100mAg−1 and good rate capability than the pure α-Fe2O3 nanorings (225mAhg−1), outperforming the most of reported Fe2O3/graphene electrode materials previously. The excellent electrochemical performance of α-Fe2O3@rGO benefits from the synergistic effect between α-Fe2O3 nanorings and graphene nanosheets. Moreover, the present work will be contributed to the future development of diverse graphene-based metal oxide materials for lithium-ion batteries applications.
This paper investigates Taiwan's strategic promotion of the photovoltaic industry, along with the warm welcome it has extended to developments and competitive trends in global green energy technology. Through gaining a grasp of Taiwan's position as fourth globally in the photovoltaic industry and production potential, the author's main concern was with the role of the government, encouraging policies, installation incentive measures, the newest ‘Renewable Energy Development Act’, Science Park cluster effect strategy, initiating National Energy projects and actively promoting and improving the competitiveness of Taiwan's photovoltaic industry. The promotion of legislation and policy-orientated strategies are all a vital path to Taiwan catching up, learning and developing competitiveness in the area of science and technology related industries. Moreover, from the perspective of technological and industrial development trends, the author carried out a SWOT analysis of Taiwan's photovoltaic industry, pointing out that with the basic niche established through Taiwan's semiconductor and IC manufacturing and design, Taiwan's photovoltaic industry has the potential to take it one step further in the areas of R&D and the possibility of acquiring breakthroughs in international cooperation.
The present study assessed the use of a voice-detecting sensor interfaced with a scanning keyboard emulator to allow two boys with extensive motor disabilities to write. Specifically, the study (a) compared the effects of the voice-detecting sensor with those of a familiar pressure sensor on the boys’ writing time, (b) checked which of the sensors the boys preferred, and (c) conducted a social validation assessment of the boys’ performance with the two sensors, employing psychology students as raters. The difference in the boys’ overall mean writing time per letter across sensors was, by the end of the study, about 1.5s. This difference favored the pressure sensor for one of the boys and the voice-detecting sensor for the other boy. Both boys showed preference for the voice-detecting sensor. Moreover, the psychology students involved in the social validation assessment indicated that such sensor was more satisfactory, suitable, and educationally relevant than the pressure sensor, and represented the solution that they as raters supported more.
Several models have been developed to estimate the operating cell temperatures of photovoltaic (PV) modules because they directly affect the performance of each PV module. In this study, two prediction models used most commonly, the nominal operating cell temperature (NOCT) model and the Sandia National Laboratory temperature prediction model (SNL), were investigated for their suitability in the prediction of PV module's temperatures for building integrated photovoltaic (BIPV) installation in the tropical climate conditions of Thailand. It was found that, in general, the SNL model tends to give better results of temperature prediction than those of the NOCT model. Nevertheless, both models are strongly over-biased in temperature predictions. The discrepancies of the predictions are basically caused by the dissimilarity of the BIPV installation and the standard installation as specified by the models, rather than the effect of differences in climatic conditions between the temperate and tropical zones. In the worst case, it was found that the highest value of the mean bias error (MBE) is +8°C, or equivalent to +21% of the mean observed temperature, and the root mean square error (RMSE) is ±10°C, or equivalent to ±24% of the mean observed temperature. However, although these errors were large, their effects on the accuracy of the final prediction of the electrical power output generated by the PV module over a long term would not be great. The error of the expected generated energy output would not be more than 6% of the averaged actual energy output, which is acceptable for most applications.
Families with lower socioeconomic status (SES) often face problems with gaining access to health care services. Information is scarce on the relationship between SES and health care delivery for children suffering from chronic pain.
The information about concentrations of dioxin in pore water, ecotoxicity and DOC and TOC content can be key factor for the prediction of the fate of dioxins in the aquatic environment as well as an ecological risk assessment. The aims of the study were to assess the concentration of PCDDs/PCDFs and ecotoxicity of pore water and to compare above results in relation to the dissolved organic carbon (DOC) and total organic carbon (TOC) content. The concentration of dioxins was assessed using an enzyme-linked immunoassay test, while the ecotoxicity of pore water was determined using a crustacean Daphnia magna and bacteria Aliivibrio fischeri. The studies were conducted on two different dammed reservoirs Rożnów (catchment basin of an agricultural character) and Rybnik (catchment basin of an industrial character) located in southern Poland. The concentration of dioxins in pore water was between 8.56 to 90.92 ng EQ/L, with a significantly higher concentration in the pore water from the Rożnów Reservoir than the Rybnik Reservoir. The DOC content in pore water was from 30.29 to 63.02 mg/L (Rożnów Reservoir) and from 35.46 to 60.53 mg/L (Rybnik Reservoir). Higher toxic responses were recorded for A. fischeri than for D. magna. Moreover a significantly higher toxicity for both tested organisms was indicated in pore water from the Rożnów Reservoir. Besides of TOC and DOC, the fine fractions of the sediments were particularly important in the concentration of dioxin in pore water. The other pore water parameters, such as pH and EC can influence the toxicity of water for organisms. The result indicate complex relationships between the PCDD/F, ecotoxicity and DOC, TOC concentration in pore water and confirms that these parameters are important in terms of water environmental contamination.
Street dust samples were collected from differing areas (industrial—medium traffic density, commercial—high traffic density, and residential 1 and 2—low traffic density) in Dhaka City, Bangladesh, and their major oxide and trace element compositions were determined. The results show significant concentrations of Pb, Zn, Cu, Ni, and Cr in the Dhaka dusts, and some variations among the four sample groups. The samples in the commercial area had Pb concentrations two- to seven-fold those of the industrial and residential areas. Contents of Zn, Cu, Ni, and Cr in the industrial areas were greater than those in the commercial and residential areas. Levels of Pb, Cu, Ni, and Cr exceeded the maximum permissible limits for common soil. Increases in these anthropogenic trace metals in the surface environment can most likely be attributed to rapid urbanization and industrialization and increased vehicle emissions to the atmosphere. Elevated Zn concentrations in an industrial area can be ascribed to discharges of industrial activities, while elevated Zn abundances in commercial areas probably originate from traffic sources. The street dusts contaminated with Cu, Ni, and Cr occur mainly in industrial areas. However, Pb contamination in the Dhaka dusts is probably caused by Pb particles from vehicle emissions.
The sluggish oxygen reduction reaction (ORR) greatly reduces the energy efficiency of solid oxide fuel cells (SOFCs). Here we report our findings in dramatically enhancing the ORR kinetics and durability of the state-of-the-art La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) cathode using a hybrid catalyst coating composed of a conformal PrNi0.5Mn0.5O3 (PNM) thin film with exsoluted PrOx nanoparticles. At 750 °C, the hybrid catalyst-coated LSCF cathode shows a polarization resistance of ∼0.022 Ω cm2, about 1/6 of that for a bare LSCF cathode (∼0.134 Ω cm2). Further, anode-supported cells with the hybrid catalyst-coated LSCF cathode demonstrate remarkable peak power densities (∼1.21 W cm−2) while maintaining excellent durability (0.7 V for ∼500 h). Near Ambient X-ray Photoelectron Spectroscopy (XPS) and Near Edge X-Ray Absorption Fine Structure (NEXAFS) analyses, together with density functional theory (DFT) calculations, indicate that the oxygen-vacancy-rich surfaces of the PrOx nanoparticles greatly accelerate the rate of electron transfer in the ORR whereas the thin PNM film facilitates rapid oxide-ion transport while drastically enhancing the surface stability of the LSCF electrode.
We investigated batteries using calcium as the transfer ion with a view to developing high energy density and safe ion-transfer type batteries as an alternative to lithium-ion batteries. The electrochemical behavior of calcium electrodes in various kinds of electrolyte solution was investigated by means of galvanostatic measurements. The anodic dissolution proceeded easily, but there was no cathodic deposition in the solutions we tested in this study. As a result, we used Ca(ClO4)2 solute/acetonitrile solution to evaluate the calcium insertion behavior. Moreover, we examined electrochemical insertion and extraction reactions with respect to calcium ions using vanadium oxides as calcium host materials. Their discharge curves indicated that a calcium insertion reaction did indeed occur. Structural changes in vanadium oxides resulting from the insertion and extraction of calcium ions were observed for the first time.
In two studies, we examined the implications psychosocial constructions of parenting hold for an understanding of well-being. In studies 1 (N = 504) and 2 (N = 98) participants provided a list of personal goals and narratives about the experience of becoming parents, respectively. In both studies, measures of well-being were also completed. Goals were categorized on the basis of whether they contained reference to parenting as well as agentic and communal motivation, whereas stories were coded for themes of exploration and resolution. In Study 1, the proportion of parenting goals related positively with well-being, although this effect was rendered non-significant after accounting for the communal motivation of parenting goals. In Study 2, themes of exploration and resolution in parents’ narratives positively predicted well-being. Collectively, these results provide intimation of parenting’s “meaningfulness” within the current socio-cultural context.
Karmarkar A, Cooper RA, Liu H, Connor S, Puhlman J. Evaluation of pushrim-activated power-assisted wheelchairs using ANSI/RESNA standards. Objective To determine and compare performance of pushrim-activated power-assisted wheelchairs (PAPAW) (iGLIDE, e-motion, Xtender) on national standards. Design Engineering performance and safety evaluation. Setting A Veteran Affairs and university-based research center. Specimens Nine PAPAWs. Interventions Not applicable. Main Outcome Measures Static, dynamic stability, brake effectiveness, maximum speed, acceleration, retardation, energy consumption, static, impact, and fatigue strength. Results There was no significant difference among the 3 models in forward stability. The iGLIDE was the most stable, whereas the e-motion was the least stable model in the rearward stability tests. All PAPAWs performed equally on the slopes of 3° and 6° in the forward and rearward directions. Braking distance was the highest for e-motion (5.64±0.28m) and the lowest (1.13±0.03m) for the iGLIDE in forward direction. The average equivalent cycles of all PAPAWs were 318,292±112,776.6 cycles (n=8) on the fatigue tests. All PAPAWs passed the impact and static strength tests. Conclusions The standards of the American National Standards Institute and the Rehabilitation Engineering and Assistive Technology Society of North America could act as quality assurance tool for wheelchairs. The standards for wheelchairs were first approved in 1990; after 17 years, exceeding the minimum values in the standards would be a reasonable expectation.
The field of biological cardiac pacing, which aims to improve upon, supplement and, eventually, to replace electronic pacing has come a long way since its inception more than a decade ago. Broadly, research has been focused on gene and cell therapy. In this Review, Rosen and colleagues highlight milestones achieved through the construction of a 'roadmap' in biological pacing, and discuss the barriers that remain to be overcome before clinical trials of biological pacing can be begun.
Synchrotron X-ray absorption edge imaging with high energy resolution was applied to study aging of fuel cell catalyst materials. The combination of an imaging and a high X-ray energy resolution set-up allows acquiring spatially resolved XAS (XANES and EXAFS) spectra. We analyzed the two-dimensional distribution of Pt and Ru in fresh and aged fuel cell catalysts. Spatially resolved XAS images were taken at the RuK edge and at the PtL3 edge. Taking radiographs above and below the absorption edges provides quantitative information about the thickness of the catalytic materials and additional chemical information. A strong influence of the flow field channels and the structure of the gas diffusion layers on the thicknesses of the catalytic elements were found: a thinner catalyst layer was found below the ribs of the flow field geometries as well as under crossing points of fiber bundles of the woven gas diffusion layers.