batterydata/paper-abstracts huggingface dataset:
Customer involvement in new product development, especially in the early stage of product conceptualisation, plays an important role for a successful product. In this study, a customer utility prediction system (CUPS) is proposed. The system comprises two modules, namely design knowledge acquisition module and customer utility evaluation module. In the design knowledge acquisition module, a knowledge acquisition technique called general sorting is utilised to establish a design knowledge hierarchy (DKH), in which design options can be generated. In the same module, customer voices towards diverse design options called customer-sensitive design criteria are solicited from customer requirements. Subsequently, in the customer utility evaluation module, a measurement for customer desirability, i.e. customer utility index (CUI), is formulated using conjoint analysis (CA) technique. Finally, the rated criteria are also used as inputs to a radial basis function (RBF) neural network for in-process customer utility prediction. A case study on cellular phone design is used to illustrate the proposed approach.
Graphite felts are often activated thermally before use in electrochemical reactors. This has the effect of improving wetting and decreasing charge-transfer resistance. In this work examination is made of the range of properties that arise within two different production charges of the same material from a single supplier. Although, it is clearly critical to know the variance within a single activated felt in order to make a fair comparison among different types of felt, this has been overlooked in previous such studies. Considerable variations were observed between two polyacrylonitrile (PAN) based felts from different production charges after thermal activation, despite both charges being of the same type of felt from one supplier. Particularly, one charge of felt lost considerably more mass and increased more in electrical double layer capacitance, on activation at a given temperature, than the other. To understand the cause of these differences the felts were examined as supplied and then after heat treatment over a range of temperatures. In the first part of this study the physical and morphological aspects of the felt are explored, before and after activating at temperatures of up to 575°C in air.
In recent years the decentralized rural electrification is becoming cost effective and convenient for areas where grid extension is very difficult. The present paper deals with the electrification of dense forest areas of Uttarakhand state in India by Integrated Renewable Energy Optimization Model (IREOM). The IREOM consists of locally available renewable energy resources such as Micro-Hydropower (MHP), biomass, biogas, wind and solar photovoltaic (SPV) systems have been used to meet electrical energy and cooking energy needs of a cluster of villages. The paper includes the selection of different system components, sizing and development of a general model to find out optimal combination of energy subsystems for the selected study area in order to minimize the cost of energy (COE) generation for a required reliability values. The sizing of different renewable energy system components has been carried out so that they are suitable for four different seasonal load profiles. The two reliability values are considered for the selection of optimum solution of year round application. The model developed for this purpose, has been found to be quite useful in optimizing the renewable energy system sizes that are available in market. The proposed model totally depends on the renewable energy systems and eliminates the use of conventional energy systems.
Twelve projects provide energy services to off-grid rural households in developing countries by enhancing markets for solar home systems and by removing barriers to their dissemination. Project approaches are reviewed, along with early implementation experience and lessons suggested by experience. Most projects incorporate the following features: pilot private-sector and NGO delivery models; pilot consumer credit delivery mechanisms; pay first-cost subsidies and offer affordable system sizes; support policy development and capacity; develop codes and standards and establish certification, testing, and enforcement institutions; and conduct consumer awareness and marketing programs. Most projects are just beginning implementation; a few are almost completed. Lessons from early experience suggest that: solar home system delivery firms face a myriad of difficulties operating in rural areas; credit risk is a serious concern of both financiers and dealers and makes credit sales particularly challenging; technical performance of systems is becoming well-proven; customers desire a range of component options and service levels and can benefit from even small systems; projects must recognize the link between rural electric-grid extension and solar home system demand; and marketing campaigns can be extremely costly and time consuming in rural areas. Challenges are to demonstrate sustainable and replicable business models, develop regulatory models for energy-service concessions, and integrate rural electrification policy with solar home system delivery.
A two-step hydrothermal approach is employed to synthesize LiMn2O4/carbon nanotube (LMO/CNT) composite powders. X-ray diffraction, scanning electron microscopy, thermal gravimetry and N2-adsorption/desorption are used to characterize their structures and compositions. Galvanostatic cycling in coin-cells is adopted to measure their electrochemical properties as cathode materials of lithium-ion batteries. A LiMn2O4 pure phase of high crystallinity is observed with CNT homogeneously dispersed in the composite network. The electrochemical properties of them are associated with two factors, i.e. the content of CNT in the hydrothermal process and the annealing temperature at the subsequent heat treatment step. Excellent rate capability of these LMO/CNT electrodes can be achieved.
It is estimated that by 2030 the world would require nearly 150 GW of battery storage playing a key role in achieving the target of 45 percent power generation from renewable sources (IRENA). Large scale Battery Management Systems (BMS) deployed to support energy storage of Electric Vehicles or off-grid storages needs efficient, redundant and optimized system. To date scheduling methods have been used to increase the efficiency as well as operating time of small scale BMS. But the same is not a practical solution for large scale BMS, as it is not fault tolerant. In literature, Re-configurable BMS (R-BMS) have been rising up as the potential solution in increasing the energy efficiency, operating time as well as reliability of BMS. In this paper a comprehensive review of the existing R-BMS topologies in literature has been investigated and reviewed. To develop a model based R-BMS, we suggest a generalized block for modelling – ‘Generalized Particle’, and break down the whole R-BMS in functional sub-blocks as sensing, control and actuation. We then identified and focused on different challenges in each of these sub-blocks which are inevitable during real time implementation, thus defining future research scopes.
The crystallization thermodynamics and kinetics of amorphous poly(ethylene terephthalate) (PET) fibres subjected to simultaneously thermal and mechanical treatments has been studied. A thermoconductive calorimeter–dilatometer was constructed in the author's laboratories with that purpose. The obtained results interpretation was based on the Ozawa's equation. Relationships between the applied to filaments mechanical stress and the running of their crystallization process were established.
The relation between working memory (WM) limitation and sentence comprehension was assessed in Hebrew-speaking aphasics, three conduction aphasics and three agrammatics. The study compared sentences that required different types of reactivation—syntactic-semantic reactivation, in relative clauses, and word form/phonological reactivation, in sentences with reanalysis of lexical ambiguity. The effect of phonological memory load, manipulated by number of words intervening between the activation and the reactivation, on comprehension of the two sentence types was examined. The findings were that agrammatic aphasics failed in the comprehension of object relatives but not on subject relatives irrespective of their antecedent–gap distance. Conduction aphasics, on the other hand, who showed severe WM limitation, comprehended well all types of relative clauses and were unaffected by antecedent–gap distance. The conduction aphasics failed to understand the sentences that required phonological reactivation when the phonological distance was long. These results suggest that the type of reactivation required by the sentence, as well as the type of memory overload are crucial in determining the effect of WM limitation on sentence comprehension.
Existing light sources for intraocular illumination are often bulky and expensive and pose a risk for the patient, because light guides are inserted in the eye through incisions and if the tip of these light guides get too close to the retina, the retina can be damaged photochemically within minutes or even seconds. Therefore a new, safe and simple device for intraocular illumination is developed and evaluated for its thermal and photochemical risks to the patient. It consists of a white LED which is integrated into a pen like holder. This device is pressed against the sclera by the physician who seeks for illumination during surgery or for diagnostic purposes. The LED light is transmitted through the sclera without the need for an incision. Considering the relevant standards, the device poses no harm to the patient, and in tests with the authors’ own eyes a sufficient intraocular illumination is reached. The proposed device is quite simple but easy to handle and very gentle for the patient.
Over the past twelve years, ideas and methods from nonlinear dynamics system theory, in particular, group theoretical methods in bifurcation theory, have been used to study, design, and fabricate novel engineering technologies. For instance, the existence and stability of heteroclinic cycles in coupled bistable systems has been exploited to develop and deploy highly sensitive, low-power, magnetic and electric field sensors. Also, patterns of behaviour in networks of oscillators with certain symmetry groups have been extensively studied and the results have been applied to conceptualize a multifrequency up /down converter, a channelizer to lock into incoming signals, and a microwave signal generator at the nanoscale. In this manuscript, a review of the most recent work on modelling and analysis of two seemingly different systems, an array of gyroscopes and an array of energy harvesters, is presented. Empirical values of operational parameters suggest that damping and external forcing occur at a lower scale compared to other parameters, so that the individual units can be treated as Hamiltonian systems. Casting the governing equations in Hamiltonian form leads to a common approach to study both arrays. More importantly, the approach yields analytical expressions for the onset of bifurcations to synchronized oscillations. The expressions are valid for arrays of any size and the ensuing synchronized oscillations are critical to enhance performance.
In this study, we report the synthesis of lamellar R-3m LiCoO2 thin films electrodes for lithium rechargeable batteries by a single step method based on an electrochemical–hydrothermal synthesis in a concentrated LiOH solution with a cobalt salt. This process combines the effect of temperature (between 150°C and 200°C), pressure and galvanostatic current. The obtained films were not annealed after the electrochemical–hydrothermal synthesis. For the first time, the theoretical study of the potential–pH diagram of cobalt was carried out at high temperature and high concentration. These calculations show that a pH value higher than 12 is necessary to avoid the direct precipitation of cobalt hydroxide Co(OH)2 inside the solution. An improvement of the soluble species stability with an increase of the temperature and a decrease of the cobalt concentration is predicted. The influence of the deposition conditions (temperature and concentration) at a constant current density was experimentally studied. X-ray diffraction (XRD) shows the formation of well-crystallized LiCoO2 thin films. Raman spectroscopy confirmed the achievement of the electrochemically active R-3m LiCoO2 phase without any trace of the Fd3m phase at temperatures as low as 150°C. Electrochemical measurements demonstrate good performances of the material synthesized between 150°C and 200°C with better capacity retention at higher temperature.
Within the framework of a German government project (initiated by the Federal Environment Agency) to check the compliance of commercially available batteries with the German Battery Ordinance concerning their heavy metal contents, 18 different types of commercially available zinc-air button cells were analysed for their cadmium, lead and mercury contents. After microwave assisted dissolution with aqua regia, Cd and Pb were determined using inductively coupled plasma mass spectrometry (ICP-MS), and Hg was determined using inductively coupled plasma optical emission spectrometry (ICP OES) and atomic absorption spectrometry. Cd contents were found to be much lower than the permitted limits; Pb contents were also found to be below the limits. Hg contents were found to be near the limits, and in one case the limit was exceeded.
Implementation of smart cities has brought a lot of comforts in our daily life. The smart cities are realized by using IT based services in the domain of transportation, health care, building management and so forth. In order to provide these services, vital information has to be sensed and disseminated using Internet-of-Things (IoT) devices, which are sparsely deployed in a smart city. These devices have low end processors and sometimes, they are installed in places where battery replacement is not feasible. In addition, they are also vulnerable to security attacks by the malicious nodes. There are a lot of recent attacks where IoT networks have been targeted by the hackers to launch a coordinated cyber attacks on some web domains. Therefore, there is a need to develop secure IoT solutions for smart cities that consume low energy. Due to its lightweight but powerful mechanisms, trust management is a promising technology to establish security for the heavily resource-constrained devices that are characteristic of the Internet of Things (IoT). In this paper, we develop an approach using trust management and investigate how it can be improved to work more energy-friendly. In particular, we adapt our mechanism to the IEEE 802.15.4 protocol. Further, we analyze the outcome of these adaptations finding out that they can reduce the active listening time of IoT nodes significantly.
A generalized mathematical model, which describes the process of lithium extraction/insertion in active material particles of insertion cathodes, is developed from linear non-equilibrium thermodynamics and the principle of electroneutrality. The model reveals theoretical relations between the intrinsic and apparent transport parameters of lithium-ions and electrons. Calculation formulas for apparent lithium-ion diffusion coefficient D 1 ⁎ are deduced from the model. A simple trial calculation is introduced to evaluate the cross-phenomenological coefficient of the Onsager reciprocal relationship. By means of referenced intrinsic diffusion coefficients, calculated by ab initio methods, calculations of D 1 ⁎ upon charge/discharge for the lithium iron phosphate cathode material (FePO4/LiFePO4) are presented. The calculated values of D 1 ⁎ are within those previously measured experimentally. In the range of lithium ion contents 0.02≤ x ≤1.0, the values of D 1 ⁎ during charge/discharge vary in the range 10−12–10−14 cm2 s−1 and decrease with increasing x. The mean value of D 1 ⁎ is about 10−13 cm2 s−1, which is five to six orders of magnitude lower than the intrinsic diffusion coefficients. The calculation results indicate that lithium ion diffusion in the active material particles is coupled with electron conduction, and the co-diffusion of lithium ions and electrons is limited by the electron conduction due to the low intrinsic conductivity of FePO4/LiFePO4.
Interdigitated carbon micro-electrode arrays for micro-capacitors are fabricated through the carbon microelectromechanical systems (C-MEMS) technique which is based on the carbonization of patterned photoresist. To improve the capacitive behavior, electrochemical activation is performed on carbon micro-electrode arrays. Cyclic voltammetry (CV) and galvanostatic charge–discharge results demonstrate that the electrochemical activation effectively increases the capacitance of the micro-electrode arrays by three orders of magnitude. Although the charge–discharge experiments show the non-ideal behavior of micro-capacitors, the specific geometric capacitance reaches as high as 75mFcm−2 at a scan rate of 5mVs−1 after electrochemical activation for 30min. The capacitance loss is less than 13% after 1000 CV cycles. These results indicate that electrochemically activated C-MEMS micro-electrode arrays are promising candidates for on-chip electrochemical micro-capacitor application.
Li2MnSiO4 has been considered as a promising cathode material with an extremely high theoretically capacity of 332 mAh g−1. However, due to its low intrinsic conductivity and poor structural stability, only about half of the theoretical capacity has been realized in practice and the capacity decays rapidly during cycling. To realize the high capacity and improve the cycling performance, Li2Mn0.8Fe0.2SiO4/carbon composite nanofibers were prepared by the combination of iron doping and electrospinning. X-ray diffraction, scanning electron microscope, and transmission electronic microscope were applied to characterize the Li2Mn0.8Fe0.2SiO4/carbon nanofibers. It was found that Li2Mn0.8Fe0.2SiO4 nanoparticles were embedded into continuous carbon nanofiber matrices, which formed free-standing porous mats that could be used as binder-free cathodes. The iron doping improved the conductivity and purity of the active material, and the carbon nanofiber matrix facilitated ion transfer and charge diffusion. As a result, Li2Mn0.8Fe0.2SiO4/carbon nanofiber cathodes showed promising improvement on reversible capacity and cycling performance.
NASICON-type Na4MnV(PO4)3 with reduced graphene oxide (rGO) has been synthesized by the simple sol-gel reaction and characterized by different analytical techniques. The resulted material has been explored as a cathode material for rechargeable non-aqueous and aqueous sodium-ion batteries. In non-aqueous electrolytes, the as-synthesized Na4MnV(PO4)3-rGO composite shows stable discharge capacity of 86 mAh g−1 at 0.1 C and 68 mAh g−1 at 0.2 C after 100 cycles in half-cell and full-cell configurations, respectively. In aqueous electrolytes, it delivers an initial discharge capacity of 92 mAh g−1 at 1 C rate in half-cells and 97 mAh g−1 at 10 C rate in full-cells having NaTi2(PO4)3-MWCNT as the anode. Stable cycleability and high rate capabilities of Na4MnV(PO4)3-rGO composite can be attributed to the very strong and sustainable conductive percolation networks for both electrons and Na+ ions. The obtained results reveal that the aqueous electrolyte cell has a huge scope for gird level energy storage applications.
The electrochemical impedance spectroscopy of battery grade copper foil and graphite-coated copper foil electrodes in 1M LiPF6 in a ternary organic carbonate electrolyte has been obtained. Detailed studies showed that both electrodes gave similar impedance spectra of two successive semicircular arcs. When overpotential was increased for both electrodes, the high frequency semicircles remained the same on each electrode, but the second semicircle increased for both electrodes. Based on the impedance spectra results of the electrodes, it appeared that the high frequency response represented a surface oxidation layer. At low frequency further oxidation occurs at both electrodes, but is kinetically controlled for bare copper, while the graphite-coated copper undergoes diffusional blocking through the porous carbon layer. An equivalent circuit of the impedance spectrum was then proposed.
Comb-shaped poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) polymers with quaternary ammonium (QA) groups have been synthesized organizing into well-defined micro-morphology for efficient anion (hydroxide) transport. These molecular comb structures show a dramatic enhancement in conductivity and water resistance compared with non-comb-shaped PPOs.
Usage of renewable and clean solar energy is expanding at a rapid pace. Applications of thermal energy storage (TES) facility in solar energy field enable dispatchability in generation of electricity and home space heating requirements. It helps mitigate the intermittence issue with an energy source like solar energy. TES also helps in smoothing out fluctuations in energy demand during different time periods of the day. In this paper, a summary of various solar thermal energy storage materials and thermal energy storage systems that are currently in use is presented. The properties of solar thermal energy storage materials are discussed and analyzed. The dynamic performances of solar thermal energy storage systems in recent investigations are also presented and summarized.
Orofacial clefts are common birth defects of multifactorial etiology. Several novel approaches have recently been applied to investigate the causes of clefts. These include examining Mendelian forms of clefting to identify genes that might also be implicated in isolated clefting, analyzing chromosomal rearrangements in which clefting is part of the resultant phenotype, studying animal models in which clefts arise either spontaneously or as a result of mutagenesis experiments, exploring how expression patterns correlate with gene function and examining the effects of gene–environment interactions. Together, these complementary strategies are providing researchers with new clues as to what mechanisms underlie orofacial clefting.
A longstanding issue in psychology is the relationship between how we perceive the world and how we act upon it. Pitch deafness provides an interesting opportunity to test for the independence of perception and production abilities in the speech domain. We tested eight amusics and eight matched controls for their ability to perceive pitch shifts in sentences and to imitate those same sentences. Congenital amusics were impaired in their ability to discriminate, but not to imitate different intonations in speech. These findings support the idea that, when we hear a vocally-imitatable sound, our brains encode it in two distinct ways- an abstract code, which allows us to identify it and compare it to other sounds, and a vocal-motor code, which allows us to imitate it.