Decrease Energy Costs Research Articles

Improving running economy through altered shoe bending stiffness across speeds

Increasing the longitudinal bending stiffness of running shoes decreases energy cost until a low point is reached, suggesting an optimal shoe stiffness. Previous research found optimal stiffness varies among individuals, however, none has determined the causes of variation both between individuals and running speeds. The primary purpose of this study was to understand how optimal shoe stiffness is affected by running speed. A secondary purpose examined the anatomical and biomechanical characteristics associated with optimal stiffness variation. Six shoe stiffness conditions were manufactured with a carbon fibre plate between the midsole and outsole of a standard running shoe. Twenty-one male runners (mass = 67.1 ± 5.0 kg, height = 178.9 cm ± 4.0 cm, age = 26.4 ± 8.4 years) completed testing at 2.98 m/s and 4.47 m/s in all shoe conditions, measuring metabolic cost, and several biomechanical and anatomical variables. Data were separated by foot strike. At the fast speed, average optimal stiffness was 19.29 ± 5.62 N/mm with a metabolic benefit of 3.02 ± 2.62%. Slow speed average optimal stiffness was 17.04 ± 6.09 N/mm with a metabolic benefit of 1.93 ± 1.82%. Only rearfoot strikers demonstrated a significant increase in optimal stiffness (p = .04) across speeds. There were no correlations between any of the measured anatomical or biomechanical variables and optimal stiffness. Optimal stiffness varied between subjects but was not correlated to any of our measured characteristics. Rearfoot striking runners may benefit from a higher stiffness shoe at faster speeds to enable optimal performance.

A INFLUÊNCIA DA TÉCNICA DE POSTUROTERAPIA NEUROSSENSORIAL NO EQUILÍBRIO DO IDOSO

The aim of the present study was to evaluate the effectiveness of manual technique of NeuroSensory Posturotherapy (PNS) applied indirectly to vestibulocochlear nerve in the balance regulation of elderly. Across-sectional study, including 53 elderly, with average age 73.5±7.0 years old, evaluated preand postthe application of the PNS on the Cyber-Sabots stabilometric platform, withopened eyes (OE) and closed eyes (CE).For the analysis of the variables obtained pre and posttechniquewith OE and CE,the Wilcoxon test was used. The results showed that after applying the PNS with OE and also CE there was a decrease ofposterior-anterior displacement (p<0.0001) and energy cost in the elderly (OE: p=0.004 and CE: p=0.020). It was concluded that there was a significant improvement in the static body balance of the elderly after applying the PNS, as OEas CE.

Oxygen Consumption While Walking With Multijoint Neuromuscular Electrical Stimulation After Stroke

This case study evaluated the effect of implanted multijoint neuromuscular electrical stimulation gait assistance on oxygen consumption relative to walking without neuromuscular electrical stimulation after stroke. The participant walked slowly with an asymmetric gait pattern after stroke. He completed repeated 6-min walk tests at a self-selected walking speed with and without hip, knee, and ankle stimulation assistance. His walking speed with neuromuscular electrical stimulation more than doubled from 0.28 ± 0.01 m/sec to 0.58 ± 0.04 m/sec, whereas average step length and cadence increased by 0.12 m and 24 steps/min, respectively. As a result, energy cost of walking with neuromuscular electrical stimulation decreased by 0.19 ml O2/kg per meter as compared with walking without stimulation while oxygen consumption increased by 1.1 metabolic equivalent of tasks (3.9 ml O2/kg per minute). These metabolic demands are similar to those reported for stroke survivors capable of walking at equivalent speeds without stimulation, suggesting the increase in oxygen consumption and decreased energy cost result from improved efficiency of faster walking facilitated by neuromuscular electrical stimulation. Although the effect of neuromuscular electrical stimulation on gait economy has implications for community walking within the user's metabolic reserves, this case study's results should be interpreted with caution and the hypothesis that multijoint neuromuscular electrical stimulation improves metabolic efficiency should be tested in a wide population of stroke survivors with varied deficits.

Erasure Coding for Ultra-Low Power Wireless Networks

In this paper, we study erasure coding for ultra-low power wireless networks with power consumption in order of milliwatts. We propose sparse parallel concatenated coding (SPCC) scheme, in which we optimize sparsity and ratio of coded packets over GF (2) (i.e., Galois field of size two) and larger field size such as GF (32) for different values of ${k}$ so that the total energy cost of the network is minimized. While high sparsity decreases energy cost of encoding, it comes at the tradeoff cost of high reception redundancy. The use of GF (2) packets minimizes the computational cost of encoding and decoding, while the use of small fraction of packets over GF (32) minimizes reception redundancies. Testbed implementation shows that SPCC energy gain increases with increasing packet generation size ${k}$ . We show that for the case where ${k}~\leq $ 40, SPCC reduces energy cost by up to 100% compared with the next best performing coding scheme.

Using real estate market fundamentals to determine the correct discount rate for decentralised energy investments

Decentralised renewable energy production (on-site energy) is potentially more profitable than commonly believed, especially in urban areas characterized with well-functioning real estate markets and low property yields. Traditional calculation methods, such as the levelized cost of energy, ignore the value on-site energy production can create to property owners through capitalizing the decreased energy costs. Past research has found that these methods are very sensitive to the discount rate, whose selection is very difficult. Evaluating the profitability of on-site energy as part of the underlying property has two major benefits: property yields, defined by real estate markets, can be used as accurate discount rates and economic value created to the property owner is quantified. To justify the use of property yields, risk profiles of energy and property investments are compared in this paper. Subsequently, a theoretical framework of on-site energy investment risks is created and demonstrated with geographical information system analysis modelling the profitability of rooftop photovoltaics in all buildings in the city of Vantaa, Finland. The findings question the traditional way of equalising the discount rates of on-site energy investments in larger geographical areas and suggest that property yields can be used as discount rates for on-site energy investments.

Utilizing renewable energy sources efficiently in hospitals using demand dispatch

Health centers and hospitals can be categorized as one of the major consumers of electrical energy in building sectors. Due to their competitive environment, they need to decrease their costs, including energy costs. On the other hand, environmental problems, lack of fossil fuels, and high energy consumption lead to using alternative energy generation methods like renewable energy sources (RESs). In this paper, we consider that the hospital can produce part of its energy from RESs for cost reduction and we implement demand dispatch energy program for using RESs efficiently. The challenge is that the main goal of hospital is providing health services not energy cost reduction. Therefore, we present a bi-objective formulation for using RESs in hospitals in a way to minimize costs and dissatisfaction by scheduling the activities of the hospital by considering hospital’s specific constraints and limitations. With the help of the proposed model, hospitals will decrease energy costs while maintaining comfort of patients and surgeons at the same time. The model is solved using real data of a hospital in Iran, and sensitivity analysis on different parameters is done. The proposed model will cause reduction in energy cost of the hospital by implementing demand dispatch program for using RESs in the hospital.

An optical mechanism for detecting the whole pyrolysis process of oil shale

Pyrolysis is one of the most widely applied method for oil shale. Although an accurate exploration of the pyrolysis mechanism of oil shale is of utmost importance to optimize the pyrolysis parameters and decrease energy cost, the typically used pyrolysis techniques fail to provide comprehensive information of entire pyrolysis process. Terahertz time-domain spectroscopy (THz-TDS), a new optical method with different sensitivities to oil, water, gas, and minerals, was used to characterize the physical properties of oil shale’s pyrolysis products The confirmed collected tendency combined with the obvious turning points indicated the four stages during the pyrolysis of oil shale, which solves the acknowledgeable difficulty in identifying the organic decomposition and the mineral reaction. Water and kerogen, which highly absorbed THz waves, were volatized and then decomposed due to the continuous increasing of THz transmittance with THz signal varying by 27.9% and 18.6% from room temperature (∼22 °C) to 500 °C. In particular, the THz signal then decreased by 153%, indicating that the more sensitive calcium oxide crystals in THz range were obtained due to the decomposition of calcite. The THz results were validated by the combination of the material analysis techniques, including thermogravimetric analysis, mass spectrometry, scanning electron microscopy, and energy-dispersive spectrometry. The results proved the ability of this spectroscopic technique to be applied in the key detection of oil shale in the petroleum industry.

Male long-distance migrant turned sedentary; The West European pond bat (Myotis dasycneme) alters their migration and hibernation behaviour.

During autumn in the temperate zone, insectivorous male bats face a profound energetic challenge, as in the same period they have to make energy choices related to hibernation, mating and migration. To investigate these energetic trade-offs, we compared the body mass of male and female pond bats (Myotis dasycneme) through the summer season, characterized the known hibernacula in terms of male or female bias, and subsequently compared their population trend during two study periods, between 1930–1980 and 1980–2015. Towards the end of summer, males began losing weight whilst females were simultaneously accumulating fat, suggesting that males were pre-occupied with mating. We also found evidence for a recent adaptation to this energetic trade-off, males have colonised winter roosts in formerly unoccupied areas, which has consequently led to a change in the migration patterns for the male population of this species. As male bats do not assist in raising offspring, males have ample time to restore their energy balance after hibernation. Our results suggest that choosing a hibernacula closer to the summer range not only decreases energy cost needed for migration, it also lengthens the mating season of the individual male. Our findings have important conservation implications, as male and female biased hibernation assemblages may differ critically in terms of microclimate preferences.

Optimal Operation for Economic and Exergetic Objectives of a Multiple Energy Carrier System Considering Demand Response Program

An MECS (multiple energy carrier system) could meet diverse energy needs owing to the integration of different energy carriers, while the distinction of quality of different energy resources should be taken into account during the operation stage, in addition the economic principle. Hence, in this paper, the concept of exergy is adopted to evaluate each energy carrier, and an economic–exergetic optimal scheduling model is formulated into a mixed integer linear programming (MILP) problem with the implementation of a real-time pricing (RTP)-based demand response (DR) program. Moreover, a multi-objective (MO) operation strategy is applied to this scheduling model, which is divided into two parts. First, the ε-constraint method is employed to cope with the MILP problem to obtain the Pareto front by using the state-of-the-art CPLEX solver under the General Algebraic Modeling System (GAMS) environment. Then, a preferred solution selection strategy is introduced to make a trade-off between the economic and exergetic objectives. A test system is investigated on a typical summer day, and the optimal dispatch results are compared to validate the effectiveness of the proposed model and MO operation strategy with and without DR. It is concluded that the MECS operator could more rationally allocate different energy carriers and decrease energy cost and exergy input simultaneously with the consideration of the DR scheme.

Let the machine do the work: learning to reduce the energetic cost of walking on a split-belt treadmill.

SECTIONSPDFPDFTOOLS SHARE The human body is capable of exploiting mechanical work provided by the external environment. A simple everyday example is the assistance provided by gravity when walking downhill, which can decrease energy cost. In recent decades, there have been numerous attempts to exploit this phenomenon in the form of wearable devices like powered exoskeletons, which can reduce the energy cost of walking (e.g. Malcolm et al . 2013). Such devices could eventually be of value to various human populations, including ageing individuals and those with gait‐related impairments.

Investigation of the energy efficiency of waste utilization technology, with considering the use of low-temperature separation of the resulting gas mixtures

Currently, there are existing technologies for high-temperature waste disposal, which use the resulting gas as fuel for recycling newly formed waste. However, the composition of waste is not constant, and contents of their components are different, thus, the need for fuel gas for burning is not stable. Therefore, such gas is constantly lost. Thus, the purpose of the article is to present the study results of the energy efficiency of high-temperature waste disposal technology, which includes low-temperature separation of the resulting gas mixtures, which allows accumulating fuel products. By means of numerical simulation an analysis of the functioning of energy-technological facility of separation of multicomponent hydrocarbon mixtures with the subsequent optimization of its parameters in order to improve its efficiency and decrease energy costs for waste gasification was performed. For this purpose, the classical approach and generally accepted thermodynamics relations were used, including the Peng-Robinson equation of state for the description of coefficients of heat-physical characteristics of working bodies. The complexity of calculation of multicomponent systems (with three and more components) does not allow application of the state diagrams. Thus, for the simulation of heat-physical characteristics the REFPROP program was employed. The energy efficiency of the proposed technology of energy resources production at waste utilization was shown. The amount of products obtained by the facility is equal to 5.242 kg/hour of the fuel product No. 1 with methane content of 99.98% and 54.76 kg/hour of the fuel product No. 2 with low quantity of methane. This confirms the economic efficiency of such technology of disposal.

Gliding patterns of Siberian flying squirrels in relation to forest structure

Abstract: It is widely accepted that the evolution of gliding ability is correlated with forest environments, but differences in gliding locomotion in relation to forest structure remains poorly elucidated in mammals. Although the cost of gliding locomotion decreases with increasing glide distance per unit vertical drop (glide ratio), gliding mammals often use costly low-ratio glides and seldom exploit maximum-ratio glides. In this study, we evaluated our hypothesis that low-ratio glides are related to forest structure by measuring glide distance, vertical drops and landing tree heights in Siberian flying squirrels (Pteromys volans), and we also recorded their behaviour in landing trees. Glide ratio decreased with increasing landing tree height. Squirrels landed on taller trees using low-ratio glides and tended to depart from them quickly without spending much time there, but used high-ratio glides to land on shorter trees for foraging or nesting. Thus, flying squirrels use two different gliding behaviours depending on their immediate objective, where inefficient low-ratio glides are used to move to higher trees for continued gliding. This approach might be necessary for efficiency and safety in subsequent glides, because taller trees facilitate long-distance glides and significantly decrease energy costs and landing impact. Therefore, the location of tall trees in forests and/or average canopy height might alter glide path routes. This study provides important evidence that forest structure affects gliding patterns and provides insight on how forest management could influence the gliding locomotion of Siberian flying squirrels.

A review on biodiesel production using eggshell as catalyst

Transesterification of fatty acid methyl ester (FAME) is the most known production method of biodiesel which has a growing popularity in the renewable clean energy sector. Energy consumption increases all around the world. To meet increasing this consumption lots of new techniques are being studied. It is important to obtain low cost and high quality energy. For biodiesel production processes it can be provided by improving reaction conditions. Conversion efficiency of transesterification process is an important parameter so various catalysts are being developed to increase it. Waste materials are good alternatives for catalyst production. There are lots of studies are being carried about using waste materials as catalyst. Cost of energy decreases and waste assessment is provided by this way. Among the heterogeneous catalysts, calcium (Ca) based catalysts are highly preferred in the transesterification reaction because of their high catalytic activity and easy accessibility. It can be obtained from especially egg shell and egg is one of the most over-consumed foodstuff across the world. Waste egg shell that is rich in terms of Ca was subjected to calcination process to obtain calcium oxide (CaO). CaO catalyst which is synthesized with high activity increased the quality of reaction. In this study efforts have been taken to review the studies that are about the biodiesel production from vegetable oil using waste egg shells as a bio-based catalyst. Optimum experimental conditions were summarized from reviewed studies.

Harmonics and Reduction of Energy Consumption in Lighting Systems by Using LED Lamps

This paper proposes the study and analysis of harmonics, energy consumption and power quality of light emitting diode (LED) lamps equipped in building lighting systems. LED lamps with external (LED MR16) and internal (LED light bulb) drivers are investigated using an experimental setup to compare the results. The power quality of both LED lamps is studied by using a power quality meter to measure the generated harmonic currents from various case studies. The case study is divided into four major cases: one LED lamp is turned on with one driver, two LED lamps are turned on using the two drivers, eight LED lamps are turned on with one driver, and eight LED lamps are turned on with the eight drivers. As harmonics are related to total power factor (PF), which affects the energy savings of the building, hence, a filtering circuit to reduce harmonic current has been designed and implemented to improve power quality and/or power factor of the system. The different cases of harmonic filter insertion at the input of an LED lamp’s driver are discussed and then compared with a lighting standard to show the effectiveness of the passive filtering technique used in the studied system. In addition, the obtained result can be applied to both newly built and retrofitted buildings that aim to use LED technology to increase energy efficiency and decrease energy costs, and could be a helpful guide for end-users and manufacturers in addressing and developing LED issues.

Influence of Acid on the Curing Process of Tannin-sucrose Adhesives

Tannin and sucrose (TS) can be used in a biomaterial-based wood adhesive that requires a higher hot pressing temperature and longer time than traditional resins. To solve these problems, hydrochloric acid and citric acid were utilized as a catalyst during the curing process to decrease energy costs (forming TSH and TSC adhesives, respectively). Thermal analysis revealed that the addition of hydrochloric acid and citric acid resulted in decreases to the thermal thresholds associated with degradation and curing. The resultant insoluble matter ratio verified that the polymerization reaction happened at a lower temperature than the adhesive without acidic conditions. The FT-IR and solid state 13C NMR spectra showed that the addition of acid compounds acted catalytically and increased the generation of 5-HMF in uncured adhesives. The dimethylene-ether bridges and methylene bridge were formed during the heat treatment. The water resistance of the particleboards manufactured by TSC and TSH adhesives were notably enhanced when the hot-pressing temperature was 180 °C. However, an increased hot pressing temperature did not improve the mechanical properties of the particleboard bonded by TSH, which was due to cellulose and hemicellulose decomposition under strong acidity conditions.

Towards Expeditionary Battlefield Manufacturing Using Recycled, Reclaimed, and Scrap Materials

The ability to manufacture at the point of need in austere environments is a very important concept for the military. Research at the US Army Research Laboratory (ARL) is showing that agile, expeditionary manufacturing could be accomplished through use of materials at or near to the location of operating bases. These materials could include not only organic and inorganic materials naturally occurring in the area but also recycled materials (metals, polymers, etc.) from operating bases as well as battlefield scrap. This idea could potentially reduce the huge logistics tail needed to conduct wars on foreign soil, saving valuable resources and lives, and allowing the warfighter to perform the mission, instead of guarding and securing convoy transports. It would be favorable for our warfighters to have access to technology that uses locally available materials, for the following reasons: improved operational readiness, decreased energy costs related to transportation, reduction of spares inventory needed in-theater, and increased self-sustainability of operating bases. This paper describes ARL’s efforts towards delivering manufacturing operations to the battlefield using recycled, reclaimed, and scrap materials for feedstock.

Computing with Spikes: The Advantage of Fine-Grained Timing.

Neural-inspired spike-based computing machines often claim to achieve considerable advantages in terms of energy and time efficiency by using spikes for computation and communication. However, fundamental questions about spike-based computation remain unanswered. For instance, how much advantage do spike-based approaches have over conventional methods, and under what circumstances does spike-based computing provide a comparative advantage? Simply implementing existing algorithms using spikes as the medium of computation and communication is not guaranteed to yield an advantage. Here, we demonstrate that spike-based communication and computation within algorithms can increase throughput, and they can decrease energy cost in some cases. We present several spiking algorithms, including sorting a set of numbers in ascending/descending order, as well as finding the maximum or minimum or median of a set of numbers. We also provide an example application: a spiking median-filtering approach for image processing providing a low-energy, parallel implementation. The algorithms and analyses presented here demonstrate that spiking algorithms can provide performance advantages and offer efficient computation of fundamental operations useful in more complex algorithms.

Adaptive Importance of Various Forms of Metabolic Processes in Marine Fish at High Latitudes

Adaptation mechanisms at the energy “budget” level in marine species of Arctic fish were studied on the basis of long-term experimental research and published data. Low rates of growth, basic metabolism and reproductive contribution are observed in poikilothermic animals inhabiting the polar regions of the World Ocean. A high level of adaptation capabilities for survival of the species was revealed. With decreased energy costs for metabolic maintenance, the volume of synthesized protein increases upon low rates of its own production, which leads to a higher efficiency of growth in polar organisms. Analysis of the van’t Hoff temperature coefficients Q10 also confirms this distinction, showing that the growth rate depends on temperature to a lesser extent than the rate of energy metabolism.

Joint Cache Content Placement and Task Offloading in C-RAN Enabled by Multi-Layer MEC.

In this paper, we work on a Cache and Multi-layer MEC enabled C-RAN (CMM-CRAN) to handle various user tasks with minimized latency and energy cost. We intend to solve two particular problems of CMM-CRAN. First, because CMM-CRAN has to maximally cache the most frequently requested data from Service Provide Server (SPS) to Remote Radio Head (RRH) and later offered to proximity mobile users, the cache content placement from SPSs to RRHs becomes a many-to-many matching problem with peer effects. Second, because of multi-layer MEC, a user task has to be dynamically controlled to be offloaded to the best fit cloud, i.e., either local MEC or remote MEC, to get served. This dynamic task offloading is a Multi-Dimension Multiple-Choice Knapsack (MMCK) problem. To solve these two problems, we provide a Joint Cache content placement and task Offloading Solution (JCOS) to CMM-CRAN that utilizes Proportional Fairness (PF) as the user scheduling policy. JCOS applies a Gale-Shaply (GS) method to work out the cache content placement, and a Population Evolution (PE) game theory coupled with a use of Analytic Hierarchy Process(AHP) to work out the dynamic user task offloading. According to the simulation results, CMM-CRAN with JCOS is proved to be able to provide highly desired low-latency communication and computation services with decreased energy cost to mobile users.

ОБЕСПЕЧЕНИЕ БЕЗОПАСНОСТИ ДВИЖЕНИЯ ПОЕЗДОВ С ПРИМЕНЕНИЕМ РАДИОТЕХНИЧЕСКИХ СИСТЕМ

PURPOSE. This paper develops a structural algorithm to automate the processes of efficiency control and monitoring of the condition of track circuits through the use of wideband signals able to provide a substantial increase of qualitative indicators of control of railway transportation safety indicators. The automation of rail circuit efficiency control is implemented by the system of blocks responsible for performing a certain task in the form of a structural model of FILAC (F-functional subsystem; I - information subsystem, L - logical subsystem, A - addressing subsystem, C - control subsystem). This model allows to create a system for the implementation of any algorithmic process of control, diagnosis and management, being the basis for the creation of the required one. METHODS. The study is based on the method of development and analysis of the automation algorithm of the processes of efficiency control and monitoring of the rail circuit condition through the use of broadband signals. It will significantly improve the qualitative indicators of control of rail transportation safety parameters. RESULTS. CONCLUSIONS. Application of new control methods and a special automation algorithm of the rail circuit efficiency control system that provides rail traffic safety through the use of radio signals will significantly improve traffic safety indicators and operation reliability as well as decrease energy costs and other. It should be noted that the new approach can significantly reduce the delay time of trains.