Balance Methodology Research Articles

Review of Battery Cell Balancing Methodologies for Optimizing Battery Pack Performance in Electric Vehicles

Batteries are gaining entry into every home and office for they are widely used because of their variant benefits. However, these batteries are prone to failure caused by charge imbalance in the batteries connected in either series or parallel, which can sometimes be catastrophic and hence they require to be properly monitored in a real-time manner. There exist many battery balancing schemes which are broadly grouped into either passive or active schemes. All these schemes have their own advantages and disadvantages, and hence it is upon the user to decide on which scheme will best work for them. However, research has proven that the hybrid scheme will be the best as it couples the benefits of all schemes. This study will review the various battery cell balancing methodologies and evaluate their relationship with battery performance. At present there are a few studies tackling the mechanical vibration of battery balancing performance. This study shows that battery balancing performance during long-term should be evaluated from various temperature and vibration frequencies.

Effectiveness of smart meter-based urban water loss assessment in a real network with synchronous and incomplete readings

The availability of smart metered high-resolution water consumption data introduces, through the synchronous readings of the smart meters, new perspectives in the proactive approach to the monitoring of water losses. Measuring or transmission systems problems are unavoidable in real-world networks and, if not appropriately addressed, may compromise the ability to use smart meters to estimate water losses. The proposed Synchronous Water Balance methodology allows the near-real time assessment of water losses taking into account incomplete readings through a water consumption data validation and reconstruction model. The impact on water loss monitoring due to the lack of an increasing number of smart meters is investigated applying a random sampling and evaluating the corresponding error. The results, tested on a district of the city of Fano (Italy), suggest that the availability of near real-time synchronous water consumption measures can substantially improve the assessment of water losses in comparison to traditional approaches.

Gravity-Balancing of Elastic Articulated-Cable Leg-Orthosis Emulator

In this paper, we propose static-balancing mechanisms to permit perfect and approximate compensation of gravitational loads for an articulated-cable leg-orthoses. Such gravity-compensation of loads (arising from both user’s leg as well as attached orthosis) can significantly improve the transparency and performance of the rehabilitation exoskeletons for gait training. The direct application of traditional static balancing methodologies (e.g. adding balancing weights or even auxiliary linkages) places a very restrictive set of conditions for mass, inertial and geometric parameters to achieve balancing for all leg postures in the configuration space. Greater design freedom and flexibility to achieve balancing conditions can be obtained by coupling semi-active elastic elements (such as coil and torsion springs) together with linkages. The effectiveness of this approach is demonstrated on a scaled physical leg-orthosis emulator in terms of significant reduction of actuation to realize the gravity-compensation.

Analysis of climate types: Main strategies for sustainable decisions in agricultural areas of Carabobo, Venezuela

Recently, the agricultural zones of Carabobo present problems with the water available for crops influenced by the fluctuation between Precipitation and Potential Evapotranspiration. It is for this reason that the need arises to analyze the climatic types according to the degree of humidity. The Climatic Hydrological Balance methodology was used for 25 rainfall stations in Carabobo, Venezuela, for a period of common registration (1969 - 1999). The results show that four regions were found where humidity behaves differently, the greatest excesses are to the south of the state and it was found that the climatological stations located north of Carabobo have a greater annual deficit. The most relevant agricultural areas are represented by a water index of (-2.16 to -18.96); which determines a dry sub-humid climate with annual rainfall ranging between 921 mm and 1063 mm. This study generated vital information in those agricultural areas that require additional irrigation or controls with structural drainage works that prevent certain crops sensitive to excess water from being damaged.

Aircraft Landing Scheduling Using Embedded Flower Pollination Algorithm

Aircraft landing scheduling is an imperative issue in the air traffic management, that aims to decide the best allocation considering the landing time for assigning to a sequence with limit the aggregate of the deviation of the actual as well as target landing time under the safe landing condition. The traditional algorithms have certain deficiencies for discrete optimizations. This paper renders an embedded flower pollination algorithm (EFPA) for aircraft landing schedule. The aircraft are classified relying on the class of each aircraft, small, large as well as heavy. Considering every single aircraft classes, runway occupation profile, landing time and separation time computation are done. EFPA is used to schedule the arrival of the airplanes. Context cognitive learning and runway balance methodology are contrived to upgrade the searching ability. The various experimental analysis and outcomes reveal that the proposed EFPA outperforms the other existing strategies when compared.

Source apportionment of atmospheric aerosol in a marine dusty environment by ionic/composition mass balance (IMB)

Abstract. PM10 aerosol was sampled in Santiago, the largest island of Cabo Verde, for 1 year, and analysed for elements, ions and carbonaceous material. Very high levels of dust were measured during the winter months, as a result of the direct transport of dust plumes from the African continent. Ionic and mass balances (IMBs) were applied to the analysed compounds, permitting the determination of six to seven different processes and source contributions to the aerosol loading: insoluble and soluble dust, sea salt, carbonaceous material and secondary inorganic compounds resulting from the reaction of acidic precursors with ammonia, sea salt and dust. The mass balance could be closed by the consideration and estimation of sorbed water that constituted 20 %–30 % of the aerosol mass. The balance methodology was compared with positive matrix factorisation (PMF), showing similar qualitative source composition. In quantitative terms, while for soil dust and secondary inorganic compound source classes, the results are similar, for other sources such as sea-salt spray there are significant differences in periods of dust episodes. The discrepancies between both approaches are interpreted based on calculated source profiles. The joint utilisation of the two methodologies, which are complementary, gives confidence in our capability for the correct source apportionment of aerosol particles.

Experimental validation of a robust model-based balancing approach

Balancing procedures are periodically applied to rotating machines to reduce vibration amplitudes, thus keeping the system operating within acceptable safety limits. Various methods have been developed to balance rotating machines, such as the so-called signal-based balancing techniques. This paper presents the experimental validation of a balancing approach dedicated to rotating machines. This approach is based on a representative mathematical model of the system and it first performs the model updating of the machine. The unbalance condition is obtained through the solution of an inverse problem by taking into account the uncertain parameters of the rotor that can affect the balancing result. This robust balancing methodology is performed by considering a mono-objective optimization method in which the uncertain parameters are represented by random variables. In the present contribution, only the unbalance distribution along the rotor is considered as uncertain information. For this aim, uncertainty was modeled as a Gaussian field and was represented by Monte Carlo simulations. The corresponding experimental investigation considers a rotor system composed of a horizontal steel shaft, three discs, and two self-alignment ball bearings. The obtained results demonstrate that the proposed approach is an effective alternative for the balancing of rotating machines.

Optimizing control dynamic complexity and production schedule

Over the last few decades sophisticated line balancing methodologies have been developed in response to the emerging trend of lean production in order to more effectively streamline production sequence scheduling. Newer approaches now demonstrate the potential to achieve lean production while at the same time simplifying what have become increasingly complex analytical methodologies and production sequences. Unlike past studies on line balancing for mixed-model production lines, in this paper the impacts of line balance on Control Dynamic Complexity are investigated and their deployment illustrated with a case study. Precedence matrices have been studied and a combined precedence matrix computed. The mathematical programming language Matlab is employed to illustrate state diagrams representing the relationships between the tasks and terminals. It is found that control dynamic complexities are higher for some particular sequences, and in such cases further explanations are offered. Furthermore, this study reveals that it is possible to minimize the complexities by better exploiting some aspects of line scheduling guidelines. Since line balancing and line scheduling are NP hard issues, this paper has also demonstrated ways in which computational analysis of multiple iterations can be significantly accelerated in future by deploying ant colony optimization techniques. Analysis of complexity level highlights what may otherwise be intuitive, that excessive sophistication of line balance techniques is very likely to be detrimental to an overall organization if resulting scheduling becomes difficult to practically monitor.

A simple analysis of flying capacitor converter

PurposeThe paper aims to emphasise how switched systems can be analysed with elementary techniques which require only undergraduate-level linear algebra and differential equations. It is also emphasised how math software can become useful for simplifying analytic complications.Design/methodology/approachThe time domain voltage balance methodology is used for stability analysis. As for deriving formulas for the asymptotic average of both capacitor voltage and inductor current, a new simple analytic method is introduced.FindingsIt was shown analytically that the time average of capacitor voltage converges to half of the source voltage. A formula for the time average of the current of the inductor is also computed. As a by-product, it was discovered that the period of the current is half of the switching period. Numerical simulations are obtained to illustrate the accuracy of the results.Research limitations/implicationsHigher dimensional generalisations could become a bit complicated, as stability analysis of higher dimensional exponential matrices is not so easy to handle. On the other hand, the new discovery on the period of the current is more likely to give new insights into handling higher dimensional systems.Practical implicationsAnalytical formulas are exact, and it helps in accurately modelling flying capacitor converts (FCCs) in practice.Originality/valueFCC is well studied in engineering society. However, not much is done in obtaining closed form solutions using analysis. Also, math software is much used in computation of numerical results and obtaining simulations. In this paper, one more important aspect of math software is emphasised, namely, use symbolic and numeric computing environment Maple in analysis.

Robust Balancing Approach for Rotating Machines Based on Fuzzy Logic

Unbalance is one of the most common malfunctions found in rotating machines generating high vibration amplitudes that can lead to fatigue and wear of rotor elements. There are several well-known balancing techniques wherein one of the most widespread approaches is the so-called influence coefficients method (IC method). Aiming to increase the robustness of the standard IC method, in this paper, a revised IC balancing methodology for rotating machines is proposed. In this sense, a preprocessing stage is applied to access the uncertainties affecting the rotating machine. In this sense, measurement data sets evaluated under the fuzzy logic approach are used. Thus, the rotor vibration responses measured over a long period are considered by means of a fuzzy transformation (defining unbalance fuzzy sets). The unbalance condition of the rotating machine is determined through a defuzzification process. This unbalance condition is then introduced in the IC method algorithm aiming at obtaining correction weights and associated angular positions that increase the balancing robustness as compared with the classical approach. Numerical and experimental studies are used to evaluate the effectiveness of the proposed methodology. The obtained results illustrate the capacity to increase the balancing overall robustness.

Análisis espacial del índice hídrico: avances en la adopción de decisiones sostenibles en territorios agrícolas de Carabobo, Venezuela

El objetivo de este estudio fue analizar espacialmente el índice hídrico (Im), permitiendo agrupar el clima de acuerdo al grado de humedad. Se utilizó la metodología del Balance Hídrico Climático (BHC) en 25 estaciones pluviométricas en Carabobo, Venezuela, para un período de registro común (1969-1999). Los resultados muestran que se encontraron cuatro regiones, donde la humedad se comporta de modo diferente, los mayores excesos son al sur del estado y se constató que las estaciones climatológicas ubicadas al norte de Carabobo presentan un mayor déficit anual. Las zonas agrícolas más relevantes están representadas por un índice hídrico de (-2,16 a -18,96); lo que determina un clima Subhúmedo seco con precipitaciones anuales que oscilan entre los 921 mm y los 1063 mm. Este estudio generó información vital en aquellas áreas agrícolas que requieren riego adicional o de controles con obras estructurales de drenaje para evitar que determinados cultivos, sensibles al exceso de agua, se perjudiquen.

Estimation and determinants of phosphorus balance and use efficiency of dairy farms in Northern Ireland: A within and between farm random effects analysis

The dairy sector is the most important agricultural sub-sector in Northern Ireland both in terms of size and contribution to the economy. However, the abolition of the milk quota regime in 2015 and the government's initiative for industry growth has given rise to concerns about environmental pollution, especially in terms of phosphorus (P) balance. In light of these concerns, this study analyses the level and determinants of P balance and use efficiency on Northern Ireland's dairy farms. The study employs the OECD/EUROSTAT nutrient balance methodology and the within-between farm random effects modelling technique on a balanced panel data set. The results show that P balance in dairy farms in the study area is relatively high. However, the more profitable dairy farms have relatively lower P balance. We also found that the amount of grass grazed, and fertilizer price have a negative and statistically significant relationship with P balance, while stocking density was found to have a positive relationship with P balance. On the other hand, the age of the farmer and the amount of grass grazed where found to have a positive and statistically significant relationship with P use efficiency. The study demonstrates that increasing the percentage of grass-based feeds reduces phosphorus balance and also has a positive impact on the profitability of the dairy farms. The study recommends that farmers in the study area should increase the percentage of grass-based feeds alongside feeding concentrates with lower phosphorus contents. A moderate level of intensification should also be maintained.

Amplifying Access to Personal Data and Potential Privacy Harm in Satakunnan v. Finland (Case Note on the ECtHR Grand Chamber Judgment)

In Court’s own words “the present case is unusual” in that it concerns the privacy interests in publicly accessible data. And as some say – hard cases make bad law. Thus, unavoidably, there are many debatable points in the judgment and indeed many of its aspects have been discussed be it in the amicus briefs submitted to the Court or in the dissenting opinion by Judges Sajo and Karakas. In the note, I focus just on some of them: the issue of foreseeability of the laws, the reasoning concerning the application of the journalistic exception to the publication, the interpretation of the concept of the contribution to the debate of public interest and the issue of potential privacy harm. Finally, I make an argument that what is most problematic in this case is not its final result, which, after all, is bound to be controversial when two fundamental rights collide, but rather the balancing methodology applied by the Court. By referring to a set of criteria not well suited for the circumstances of the case and giving deference to the findings of the domestic court without proper assessment of all the aspects of the rights at issue, the Court proceeded with interpreting the notion of journalism unnecessarily narrowly. Consequently, the Court perpetuated within the scope of Article 10 ECHR certain understanding of this notion previously construed by national courts within the scope of application of Data Protection Directive.

A Harmonic Balance Methodology for Circuits with Fractional and Nonlinear Elements

This paper discusses the ability to obtain periodic steady-state solutions for fractional nonlinear circuit problems. For a class of nonlinear problems with fractional derivatives (based on the Caputo or Riemann–Liouville definitions), a methodology is proposed to derive equations representing the dependencies between the harmonics of the sought variables. Two approaches are considered for how to address the apparent nonlinear dependencies: one based on symbolic computation and the other a numerical approach based on the analysis of time functions. An example problem with fractional and nonlinear elements is presented to illustrate the usefulness of the proposed methodology. Two error criteria are introduced to verify the accuracy of the obtained results. The methodology is mainly designed to provide referential solutions in analyses of the numerical method called SubIval (the subinterval-based method for computation of the fractional derivative in initial value problems).

Stabilization and Equilibrium Control for Electrically Cart–Seesaw Systems by Neuro-fuzzy Approach

Compared to completely control systems, super-articulated mechanical systems (SAMS) are controlled under-actuated systems where the dimensions of the control input space are less than the magnitudes of the output. Hence, the major aim of this study is developing an innovative cart–seesaw system which is manipulated by electrical servo actuators and also improving balancing methodology for such apparatus. Controlling the mobile cart on the seesaw is exceptionally hard because it is an under-actuated machinery. With the purpose of the stabilization, the famous PID control scheme will be based on the genetic algorithm (GA) to pursue the main optimum parameters, and then enhancement of a fuzzy logic approach to stabilize the nonlinear model. The final controller will be completed by treating an intelligent fuzzy logic controller (FLC) based on adaptive neuro-fuzzy inference system (ANFIS) with GA tuning approach to speed up the effectiveness of controller construction. The knowledge base of fuzzy system was subsequently built on PID performance-related information. Experimentation shows that applying the suggested new cart–seesaw system (CSS) shows better functioning than the previous pneumatic cart–seesaw (PCS) system in tracking and balancing execution. Furthermore, the balancing approach presented in this paper meaningfully indicates the valuableness of the suggested intelligent controller in suppression oscillation of the seesaw. The investigation of the proposed system will be useful for control course apparatus and also worthy for the entertainment device.

ECAC Use Case of Optimised Pre-tactical Time of Arrival Adjustments to Reduce Probability of Separation Infringements

Currently, a maximum allowable number of aircraft (A/C) entering and or within a sector for a given period is fixed. Anytime this threshold is reached, involved A/C are regulated by Air Traffic Flow and Capacity Management (ATFCM) to maintain an acceptable Air Traffic Controllers’ (ATCOs’) workload. This threshold is determined regardless of particular expected air traffic complexity, which may result from potential conflicts inherently in A/C’s flight plans that may greatly affect the ATCOs’ workload. This paper proposes a new ATFCM Demand and Capacity Balancing (DCB) methodology, applied to mitigate potential conflicts between A/C’s trajectories at pre-flight level, in order to reduce the current ATCO’s workload attributed to Separation Management (SM) interventions. This purpose is achieved through minor adjustments on A/C’s Times of Arrival (TOAs) at conflicted en-route junctions. The adjustments of A/C’s TOAs are implemented through minor changes on A/C’s speed profile, applied before and after each conflicted junction, while maintaining each A/C’s departure and Targeted Time of Arrival(TTA) at destination. The paper postulates that these TOA adjustments could be easily transformed into pre-tactical ATFCM DCB measures, assuming that ATFCM will issue Reference Business Trajectories (RBTs) containing time constraints at junctions, introduced to reduce the probability of conflicts. A case study of European Civil Aviation Conference (ECAC) air traffic network using real flight plan data is presented to show the validity of the methodology.

A Study on the Balanced Assignment of Allocating Large Group with Multiple Attributes into Subgroups

In this paper, a balanced assignment methodology is proposed in case of entity with more than 2 attributes. The Mahalanobis distance is a basic idea of MTS method as a distance indicator considering the correlation of entities in quality control techniques. This can be applied to ensure the balanced assignment, and utilized the Signal to Noise Ratio as a measure of classifying large groups with entities into many subgroups. In order to analyze the balanced assignment, the simulation is performed for a given example. Validations against simulation data establish the effectiveness of this approach.

Energy analysis of ethanol from sugarcane irrigated with treated domestic sewage

Using energy balance methodology, this study compared the sustainability of ethanol synthesis from sugarcane irrigated with different replacement levels based on the evaporation estimated in a Class A pan (ECA), using treated domestic sewage effluent and groundwater as the water source, in Aquiraz, in the State of Ceara. The adopted statistical design was of randomised blocks in split plots, with four replications. Two water sources (treated sewage effluent and groundwater) were evaluated in the plots, and five irrigation levels (50, 75, 100, 125 and 150% of the ECA) were evaluated in the split plots. Irrigation with treated domestic sewage effluent results in greater energy expenditure. The irrigation depth relative to 150% of the ECA expends the most energy, irrespective of the water source. Irrigation with treated domestic sewage effluent gives a higher energy yield (368.9 GJ ha-1) through the application of a depth of 781.4 mm, while for irrigation with groundwater, 937.6 mm (150% of the ECA) is the best recommended depth for obtaining the highest energy yield (276.9 GJ ha-1). Domestic sewage effluent gives the best energy return, and its use in systems of crop-production is viable.

Complementary Irrigation in a Maize Silage Double Crop using the BAHICU Software: A Case Study in Northern Buenos Aires, Argentina

Northern Buenos Aires (Argentina) is a rain fed agricultural region. Complementary irrigation, which is mainly used in maize crop, requires the contemplation of strategies that minimize the soil solidification risk. The first alternative to mitigate the limited water quality is to perform an irrigation schedule by using the water balance methodology. The BAHICU software, developed in the study region, is a soil water balance model for agricultural systems under irrigation. The objective of the present study was to evaluate the forage production of irrigated and rain fed double crop of silage maize, using the BAHICU software as a tool to make a more efficient water use and to attenuate the adverse effect of the sodium present in the irrigation water. A field experiment was conducted on a clay soil with a sequence of two maizes during the 2015-2016 growing season: short season maize (maize 1) and late sown maize (maize 2). There were two preceding winter crops: ryegrass and oat. Plant height, dry matter (DM) percentage and DM yield were measured. Crop evapotranspiration (ETc) of irrigated and rain fed treatments was obtained from the BAHICU software. Irrigation was applied using a sprinkler system. Irrigation influenced only the yield of maize 2. Water use efficiency (WUE) did not vary with irrigation incorporation. Maize 2 presented higher forage production and WUE than maize 1. An R2 value of 0.82 was found after relating DM yield with maize ETc. The preceding winter crops only influenced the yield of the maize 1. The DM yield was linked to plant height. The irrigated maize 2 was the only treatment that presented an optimal DM percentage for silage conservation. Using the BAHICU software allowed comparing the WUE of the maizes analyzed. Irrigation influenced crop yield but not WUE.

A new load balance methodology for container loading problem in road transportation

The load balance aspect of the Container Loading Problem (CLP) has been handled in an simplified way in the literature. Either load balance has been treated as a soft constraint or the geometrical centre of the container has been assumed to be the ideal location for the centre of gravity of the cargo, or both, which does not meet regulatory directives and transportation legislation. In this paper, we treat load balance as a hard constraint and adopt vehicle specific diagrams that define the feasibility domain for the location of the centre of gravity of the cargo, according to the vehicle specific technical characteristics, thus fulfilling and complying with real-world regulations and legislation. We propose a multi-population biased random-key genetic algorithm (BRKGA), with a new fitness function that takes static stability and load balance into account. Extensive computational experiments were performed with different variants of the proposed approach. Also solutions taken from the literature were evaluated in terms of load balance. The computational results show that it is possible to obtain stable and load balanced solutions without compromising the performance in terms of container volume utilization, and demonstrate also the advantage in incorporating load balance in the packing generation algorithm.