Energy

Article	Citations
Sustainability evaluation of a heavy-duty diesel engine used in railways	691
ICEE2022 – ENERGY special issue	617
Comment on “Steam methane reforming in a microchannel reformer: Experiment, CFD-modelling and numerical study” [Energy 237 (2021) 121624]	487
The operating parameter optimization of spark duration effect on the performance and emission characteristics of direct-injection propane by genetic algorithm	413
Improvement of wind turbine aerodynamic performance by vanquishing stall with active multi air jet blowing	353
Decarbonizing urban passenger transportation: Policy effectiveness and interactions	324
A novel V-shaped layout method for VIV hydrokinetic energy converters inspired by geese flying in a V-Formation	313
Thermodynamic study on the effects of operating parameters on CaO-based sorption enhanced steam gasification of biomass	307
A frame work for comparative wear based failure analysis of CNG and diesel operated engines	296
Optimal operation of integrated power and thermal systems for flexibility improvement based on evaluation and utilization of heat storage in district heating systems	276
Using energy consumption constraints to control the freight transportation structure in China (2021–2030)	266
Impact of forecasted heat demand on day-ahead optimal scheduling and real time control of multi-energy systems	243
A novel method of battery pack energy health estimation based on visual feature learning	234
Comprehensive 4E (energy, exergy, exergoeconomic, and exergoenvironmental) analysis and optimization of wastewater sludge gasification: A case study in a resource-constrained area	229
An artificial intelligence strategy for multi-objective optimization of Urea-SCR for vehicle diesel engine by RSM-VIKOR	228
Enhancing ammonia combustion performance using hydrogen peroxide-enriched air: A computational fluid dynamics analysis	219
A systematic methodology for selecting optimal technology for waste heat utilization in food processing industry	219
The balance effects of momentum deficit and thrust in cumulative wake models	216
Multi-time scale operation optimization of integrated power and thermal system considering load disturbance	210
Real options analysis for regional investment decisions of household PV-ESS in China	208
Numerical study on the performance of a new integrated afterburner under a wide range of bypass ratio conditions	205
Analysis of a coupled calcium oxide-potassium carbonate salt hydrate based thermochemical energy storage system	204
An event-triggered and dimension learning scheme WOA for PEMFC modeling and parameter identification	204
Numerical study on thermal storage and exothermic characteristics of subway station fresh air shaft surrounding rock	203
Experimental study of a linear Fresnel concentrator: A new procedure for optical and heat losses characterization	200

Modeling impacts of different data transmission delays on traffic jam, fuel consumption and emissions on curved road	200
System design for 700 °C power plants: Integration scheme and performance evaluation	197
Flame behaviour and flame location in large-eddy simulation of the turbulent premixed combustion	193
Spatial correlation, driving factors and dynamic spatial spillover of electricity consumption in China: A perspective on industry heterogeneity	191
A multi-objective formulation of improving flexibility in the operation of electric power systems: Application to mitigation measures during the coronavirus pandemic	191
Knock analysis of bio-butanol in TISI engine based on chemical reaction kinetics	188
Numerical study on performance of a hybrid indirect evaporative cooling heat recovery heat pump ventilator as applied in different climatic regions of China	187
Simulations and experimental study to compare the behavior of a genset running on gasoline or syngas for small scale power generation	186
Enhanced thermal conductivity and adsorption rate of zeolite 13X adsorbent by compression-induced molding method for sorption thermal battery	184
Developing a 20-year high-resolution wind data set for Puerto Rico	183
3E analyses and multi-objective optimization of a liquid nitrogen wash based cogeneration system for electrical power and LNG production	181
Electrochemical conversion of CO2 using different electrode materials in an Li–K molten salt system	181
Staged supply of fuel and air to the combustion chamber to reduce emissions of harmful substances	178
Performance analysis of sorption thermal battery for high-density cold energy storage enabled by novel tube-free evaporator	177
A bilevel approach to multi-period natural gas pricing and investment in gas-consuming infrastructure	175
Analysis on flow and heat transfer performance of SCO2 in airfoil channels with different fin angles of attack	175
Optimization of Savonius rotor blade performance using Taguchi method: Experimental and 3D-CFD approach	174
Parallel electrodes gliding plasma: Working principles and application in dry reforming of methane	173
Effect of natural and forced charge air humidity on the performance and emissions of a compression-ignition engine operating at high warm altitude	168
Comparative study of energy losses related to the ring pack operation in homogeneous charge compression ignition and spark ignition combustion	166
Optimization of a segmented thermoelectric generator with various doping amounts using central composite design, multi-objective genetic algorithm, and artificial neural network	165
Comparison of the effect of linear and two-step fast charging protocols on degradation of lithium ion batteries	164
A two-dimensional distributed activation energy model for pyrolysis of solid fuels	162
Energy, exergy and environmental life cycle assessment on the valorization of an ejector integrated CCHP system with six sustainable refrigerants	161
Stage-based exergy analysis for a modern turboprop engine under various loading	160
Highly efficient portable atmospheric water harvester with integrated structure design for high yield water production	159
Simultaneous retrofit of direct and indirect Heat Exchanger Storage Network (HESN) via individual batch process stream mapping	157
Evolutionary game study and empirical analysis of the adoption of green coal mining technology: A case study of ITMDB	155
Influence of ammonia cofiring ratio and injection mode on the NO emission and control mechanisms of NH3-CH4 cofiring	155
Optimal estimation of the PEM fuel cells applying deep belief network optimized by improved archimedes optimization algorithm	152
In-depth study on the synergistic conversion mechanism of iron ore with waste biochar for co-producing directly reduced iron (DRI) and syngas	152
Chain explosion behaviors induced by discontinuous methane/air distribution	151
Structures and contributions of active substances in the latent oxidation of coal based on the oxygen isotope tracer method	151
Thermodynamics-based data-driven combustion modelling for modern spark-ignition engines	149
Experimental investigation on the large temperature lift heat pump with an integrated two-stage independently variable frequency compressor	149
Low-carbon economic operation of commercial park-level integrated energy systems incorporating supply and demand flexibility	149
Vortex interactions and loss mechanisms in the tip region of axial turbine rotors with cutback squealer tip	148
Design and performance analysis of a passive rotatable deflector diversion tail for tidal current power generation hydrokinetic turbines	147
Forecasting European Union allowances futures: The role of technical indicators	147
Pore-to-meter scale modeling of heat and mass transport applied to thermal energy storage: How local thermal and velocity fluctuations affect average thermal dispersivity	146
3D pore structure characterization and permeability anisotropy visualization simulation of fusain	146
Thermal decomposition mechanism and thermal stability prediction of n-pentane/n-butane mixture	146
Heterogeneous impacts of oil prices on China's stock market: Based on a new decomposition method	146
Hybrid energy-based electric vehicles charging station integrated with INVELOX wind turbine: A case study of Kermanshah	145
Conversion of steam power plant into cogeneration unit - Case study	145
Thermodynamic and exergoeconomic analysis of an innovative cogeneration of power and freshwater based on gas turbine cycle	145
The impact of energy-related uncertainty on China’s overall and sectoral stock returns: Evidence from quantile-on-quantile regression	143
A hybrid deep learning model towards flow pattern identification of gas-liquid two-phase flows in horizontal pipe	143
Electrifying end-use demands: A rise in capacity and flexibility requirements	142
An update to the Sandia method for creating Typical Meteorological Years from a limited pool of calendar years	142

Standalone and system-level perspectives on hydrogen-based sustainable aviation fuel pathways for Denmark	142
Ammonia/syngas combustion in a premixed micro-gas turbine: LES-FGM investigation on flame dynamics, stability, and emission control	141
A transient gas pipeline network simulation model for decoupling the hydraulic-thermal process and the component tracking process	140
Insight into the whole from the part: Redefined state of health for lithium-ion batteries based on optimal charging fragment search	140
Exergy performance analysis of hydrogen recirculation ejectors exhibiting phase change behaviour in PEMFC applications	139
Morphological and chemical differences within superheater deposits from different locations of a black liquor recovery boiler	138
Design of Electrical Submersible Pump system in geothermal wells: A case study from West Anatolia, Turkey	137
Building-integrated photovoltaics (BIPV): A mathematical approach to evaluate the electrical production of solar PV blinds	137
Co-pyrolysis of corn stalk and polyethylene at a gas phase contacting mode and aromatization mechanism study	136
A convolutional block multi-attentive fusion network for underground natural gas micro-leakage detection of hyperspectral and thermal data	136
Multi-agent deep reinforcement learning-based cooperative energy management for regional integrated energy system incorporating active demand-side management	136
Mathematical and experimental investigation about the dual-source heat pump integrating low concentrated photovoltaic and finned-tube exchanger	133
Integrated thermal modeling and parametric study of liquid hydrogen storage tanks: Effects of insulation design and operating conditions	133
Sizing utility-scale photovoltaic power generation for integration into a hydropower plant considering the effects of climate change: A case study in the Longyangxia of China	133
Exploring preferences for household energy technology adoption from a spatiotemporal perspective: Evidence from demographics, the economy, and the environment	131
Experimental study on influence of high exhaust backpressure on diesel engine performance via energy and exergy analysis	130
Development of voltage stability-based bus dependency matrix for modern power networks	130
Performance assessment of a coupled device of thermoradiation cell and photovoltaic cell for energy cascade utilization	129
Ensuring power quality and demand-side management through IoT-based smart meters in a developing country	128
A detached-eddy simulation study on assessing the impact of extreme wind conditions on load and wake characteristics of a horizontal-axis wind turbine	128
Prediction of regional wind power generation using a multi-objective optimized deep learning model with temporal pattern attention	128
Distribution network expansion planning considering a distributed hydrogen-thermal storage system based on photovoltaic development of the Whole County of China	128
A wind speed forecasting model using nonlinear auto-regressive model optimized by the hybrid chaos-cloud salp swarm algorithm	127
Public spending for environmental protection in the UK: The environmental impact of environmental taxes, renewable energy, and nuclear energy	127
Study on microscale stress sensitivity of CO2 foam fracturing in tight reservoirs	127
Novel green hydrochar production for renewable fuel substitutes, and experimental investigation of its usability on CI engine performance, combustion, and emission characteristics	126
A hierarchical energy management strategy for PHEVs: Optimizing SOC trajectory tracking performance using adaptive initial equivalent factor strategy (AIEFS)	126
Attractivity analysis of hybrid energy generation based on current energy market scenarios in Brazil	126
Novel integrated process for simultaneous diesel and electricity production from flare gases: Environmental optimization and sustainability analysis	125
A two-stage optimal operation strategy for community integrated energy system considering dynamic and static energy characteristics	124
Tail risk contagion and safe haven dynamics: Analyzing U.S. market implied volatility effects on China's energy futures	124
An energy system model-based approach to investigate cost-optimal technology mixes for the Cuban power system to meet national targets	123
Feasibility of green roofs in the mediterranean region: A stochastic study using a Monte-Carlo financial model	123
Effective wind speed estimation study of the wind turbine based on deep learning	122
Combustion and interaction mechanism of 2,3,3,3-tetrafluoropropene/1,1,1,2-tetrafluoroethane as an environmentally friendly mixed working fluid	121
A novel VSP-based CO2 emission model for ICEs and HEVs based on internally observable variables: Engine operating speeds	121
Electric vehicle charging scheduling considering infrastructure constraints	120
Real-time dispatch of an integrated energy system based on multi-stage reinforcement learning with an improved action-choosing strategy	120
Risk analysis and production safety design of supercritical carbon dioxide storage in gasification combustion cavity	120
Nitrogen migration in sewage sludge chemical looping gasification using copper slag modified by NiO as an oxygen carrier	119
Thermodynamic and economic performance analysis of a liquid carbon dioxide energy storage system coupled with absorption refrigeration cycle	119
WITHDRAWN: Optimizing Energy Management in Smart Grid Systems with GJO-THDCNN Hybrid Approach	119
Prognosability regularized generative adversarial network for battery state of health estimation with limited samples	119
Cooling performance of compression-absorption cascade system with novel ternary ionic-liquid working pair	118
Numerical study on ammonia injection location of ammonia and low-rank coal cofiring in 1000 MWe ultra super critical carolina-type boiler	118
Drivers of coal consumption changes: A decomposition analysis for Chinese regions	118
A data-driven method for heat loss estimation from district heating service pipes using heat meter- and GIS data	117
Information gap-based multi-objective optimization of a virtual energy hub plant considering a developed demand response model	117
Recurrent attention encoder–decoder network for multi-step interval wind power prediction	117
Increasing tolerable coupling coefficients range of series-series compensated inductive wireless power transfer systems operating in restricted sub-resonant frequency region with constant current outp	115
Techno-economic analysis on a hybrid system with carbon capture and energy storage for liquefied natural gas cold energy utilization	115
Electrical, thermomechanical and cost analyses of a low-cost thermoelectric generator	115
Deeppipe: A two-stage physics-informed neural network for predicting mixed oil concentration distribution	115
Stochastic bi-objective optimization for closed wet cooling tower systems based on a simplified analytical model	115
Numerical study on temperature rise and structure optimization for a three-phase gas insulated switchgear busbar chamber	114
Energy efficiency analysis and optimization of a pressurized oxy-fuel circulating fluidized bed combustion system	113
Wave excitation force forecasting using neural networks	113
Life cycle assessment and life cycle cost analysis of surgical mask from production to recycling into hydrogen process	113
A novel methodology for evaluating the inhibitory effect of chloride salts on the ignition risk of coal spontaneous combustion	113
Recursive identification of kernel-based hammerstein model for online energy efficiency estimation of large-scale chemical plants	113
Power allocation strategy for fuel cell distributed drive electric tractor based on adaptive multi-resolution analysis theory	112
Modeling and assessing the integration of CO	112
Battery performance optimization and multi-component transport enhancement of organic flow battery based on channel section reconstruction	112
Site selection decision for biomass cogeneration projects from a sustainable perspective: A case study of China	112
Comprehensive approach to static firing tests of micro gas turbine engines powered by liquid fuels	111
Multipath retrofit planning approach for coal-fired power plants in low-carbon power system transitions: Shanxi Province case in China	111
The impact of platform motion phase differences on the power and load performance of tandem floating offshore wind turbines	111
Design of dual-channel Swiss-roll reactor for high-performance hydrogen production from ethanol steam reforming through waste heat valorization	111
Parametric study of cavity on the performance of a hydrogen-fueled micro planar combustor for thermophotovoltaic applications	110
Exploring the nexus between fiscal decentralization and energy poverty for China: Does country risk matter for energy poverty reduction?	110
A novel data center air conditioner and its application scheme balancing high-efficiency cooling and waste heat recovery: Environmental and economic analysis	110
Activated waste cotton cellulose as renewable fuel and value-added chemicals: Thermokinetic analysis, coupled pyrolysis with gas chromatography and mass spectrometry	109
Analysis of the thermodynamic performance of the SOFC-GT system integrated solar energy based on reverse Brayton cycle	109
Dynamic nonlinear effects of geopolitical risks on commodities: Fresh evidence from quantile methods	109
Harmonizing energy audit reporting: Addressing data loss and policy challenges in the EU member states	109
Total travel costs minimization strategy of a dual-stack fuel cell logistics truck enhanced with artificial potential field and deep reinforcement learning	108
Study on the application of a dynamic photovoltaic integrated light shelf for office buildings	108
Production of gasoline and diesel-like fuel from natural rubber scrap: Upgrading of the liquid fuel properties and performance in a spark ignition engine	108
Development of black-ice removal system with latent heat thermal energy storage and solar thermal collectors	108
Investigation of creep and transport mechanisms of CO2 fracturing within natural gas hydrates	107

Characteristics of instability and suitable early-warning indicators for cornstalk-fed anaerobic digestion subjected to various sudden changes	107
Effects of wind loads on the solar panel array of a floating photovoltaic system – Experimental study and economic analysis	107
Transcritical CO	107
Energy use rights trading and carbon emissions	106
Effects of gas occurrence pattern on distribution and morphology characteristics of gas hydrates in porous media	106
Energy consumption, structural transformation and related carbon dioxide emissions of rural households on the Tibetan plateau	106
Working mechanism and characteristics analysis of a novel configuration of a supersonic ejector	106
Selection of second-generation crop for biodiesel extraction and testing its impact with nano additives on diesel engine performance and emissions	106
Conceptual design, exergoeconomic analysis and multi-objective optimization for a novel integration of biomass-fueled power plant with MCFC-cryogenic CO2 separation unit for low-carbon power productio	105
Rural digital credit and residential energy consumption: Evidence from the agricultural production perspective	105
Effects of gas components, reservoir property and pore structure of shale gas reservoir on the competitive adsorption behavior of CO2 and CH4	105
Numerical investigation on performance of solar chimney power plant with three wind resistant structures	105
Comprehensive competitiveness assessment of four coal-to-liquid routes and conventional oil refining route in China	105
Research on high fidelity modelling and optimum designing of an adaptive cycle engine's starting process	105
Thermal decomposition of polyolefins under different oxygen content. Composition of products and thermal effects	105
Day-ahead scheduling of energy hubs with parking lots for electric vehicles considering uncertainties	104
Deep reinforcement learning-based eco-driving control for connected electric vehicles at signalized intersections considering traffic uncertainties	104
Learning spatiotemporal dynamics in wholesale energy markets with dynamic mode decomposition	104
The determinants of oil consumption in Tunisia: Fresh evidence from NARDL approach and asymmetric causality test	103
Biogas potential of cup plant and willow-leaf sunflower biomass	103
Comparative analysis of the environmental impacts of Australian thermal power stations using direct emission data and GIS integrated methods	103
Is total system cost minimization fair to all the actors of an energy system? Not according to game theory	102
Prospective environmental and techno-economic assessment of steam production by means of heat pipes in the steel industry	102
Comparative study on monthly natural gas vehicle fuel consumption and industrial consumption using multi-hybrid forecast models	102
Multi-agent-based energy management for a fully electrified residential consumption	102
Semi-clathrate hydrate slurry as a cold energy storage and transport medium: Rheological study, energy analysis and enhancement by amino acid	102
Effect of injection pressure adjustment towards performance, emission and combustion analysis of optimal nahar methyl ester diesel blend powered agricultural diesel engine	102
Gas utilization optimization and exergy analysis of hydrogen metallurgical shaft furnace	102
Multi-component modeling and simulation of a new photoelectrochemical reactor design for clean hydrogen production	101
Performance evaluation of a concatenated stepped solar still system loaded with different masses of energy storage material	101
Microfluidic experiments and numerical modeling of pore-scale Asphaltene deposition: Insights and predictive capabilities	101
Properties and performance of hybrid suspensions of MPCM/nanoparticles for LED thermal management	101
Model predictive control for a heat booster substation in ultra low temperature district heating systems	101
FlexNet: A warm start method for deep reinforcement learning in hybrid electric vehicle energy management applications	101
Thermodynamic responses of bleed air on separated flow high by-pass turbofan engine under constant speed and constant thrust cases	100
Multi-objective optimization of the aircraft environment control system based on component-level parameter decomposition	100
An overview of non-Gaussian state-space models for wind speed data	100
Security assessment and preventive control of combined electricity and heat systems with distributed electric thermal storage	100
Optimal insulation layer for heated water pipes under technical, economic and carbon emission constraints	100
Evaluating energy flexibility requirements for high shares of variable renewable energy: A heuristic approach	99
Impact of typical and actual weather years on the energy simulation of buildings with different construction features and under different climates	99
Migration mechanism of pyrolysis oil during oil shale in situ pyrolysis exploitation	99
Evaluation of hosting capacity of the power grid for electric vehicles – A case study in a Swedish residential area	99
Design and thermodynamic analysis of an advanced liquid air energy storage system coupled with LNG cold energy, ORCs and natural resources	99
A nationwide multi-location multi-resource stochastic programming based energy planning framework	99
The efficiency of innovative technologies for transition to 4th generation of district heating systems in Ukraine	98
A Nash bargaining model for energy sharing between micro-energy grids and energy storage	98
Cooperative control method considering efficiency and tracking performance for unmanned hybrid tractor based on rotary tillage prediction	98
Improving energy efficiency prediction under aberrant measurement using deep compensation networks: A case study of petrochemical process	98
Numerical exploration and experimental validation of a tri-generation heat pump system in cooling mode	98
Energy analysis during cold start and warm up period of a methanol engine hybrid power system under several novel energy conversion strategies	98
Hierarchical model predictive control for energy management and lifespan protection in fuel cell electric vehicles	98
Adaptive NMPC-based active stability comprehensive control for aero-engine compressors	97
Design and application of a hybrid predictive control framework for carbon capture in pressurized circulating fluidized bed coal-fired processes	97
Efficient tetracycline degradation and electricity production in photocatalytic fuel cell based on ZnO nanorod/BiOBr/UiO-66-NH2 photoanode and Cu2O/CuO photocathode	97
Analysis of energy utilization and thermal efficiency in diesel engines under varying EGR rates	97
Towards a cleaner future: A novel approach to enhance energy efficiency in the US manufacturing industry with fuzzy logic-TOPSIS	97
Adaptive engineering-assisted deep learning for battery module health monitoring across dynamic operations	97
Appliance energy efficiency policies and electricity consumption: Evidence from China	97
Low-carbon planning for integrated power-gas-hydrogen system with Wasserstein-distance based scenario generation method	96
Performance study of a control valve with energy harvesting based on a modified passive model	96
Multi-objective optimization of an off-grid CAES-based cogeneration plant for quad-generation	96
Dynamic modeling and comprehensive analysis of direct air-cooling coal-fired power plant integrated with carbon capture for reliable, economic and flexible operation	96
Power quality evaluation of photovoltaic grid interfaced cascaded H-bridge nine-level multilevel inverter systems using D-STATCOM and UPQC	96
Performance analysis of a novel multi-production design via the integration of medical waste plasma gasification and waste tire pyrolysis	96
Oxy-hydrogen, solar and wind assisted hydrogen (H2	96
Advancing building intelligence: Developing and implementing standardized Smart Readiness Indicator (SRI) on-site audit procedure	96
Effects of hydrogen volume fraction, air fuel ratio, and compression ratio on combustion and emission characteristics of an SI ammonia-hydrogen engine	95
Receiving energy analysis and optimal design of crystalline silicon solar cell array on solar airship	95
Multi-objective optimization of a small turbojet engine energetic performance	95
Solar power tower plants with Bimetallic receiver tubes: A thermomechanical study of two- and three-layer composite tubes configurations	95
Study on fluidized roasting of spent hydrodesulphurisation catalysts in large-scale industrial boiling furnace by CFD simulation	94
Bi-level stochastic real-time pricing model in multi-energy generation system: A reinforcement learning approach	94
Creating a labeled district heating data set: From anomaly detection towards fault detection	94
Fair trading strategy in multi-energy systems considering design optimization and demand response based on consumer psychology	94
Combined cooling and power cycle for engine waste heat recovery using CO2-based mixtures	94
Syntheses, catalytic performances and DFT investigations: A recent review of copper-based catalysts of methanol steam reforming for hydrogen production	94
Multimodal multi-objective hierarchical distributed consensus method for multimodal multi-objective economic dispatch of hierarchical distributed power systems	94
Experimental and numerical investigations on NH3/H2 fueled combustion in the combustor with block for improved micro power generation	93
Carbon dioxide utilization based on exergoenvironmental sustainability assessment: A case study of CO2 hydrogenation to methanol	93
An energy self-circulation system based on the wearable thermoelectric harvester for ART driver monitoring	93
Multi-energy flow calculation in integrated energy system via topological graph attention convolutional network with transfer learning	93
Ensemble learning for predicting average thermal extraction load of a hydrothermal geothermal field: A case study in Guanzhong Basin, China	93
Convergence characteristics and distribution patterns of residential electricity consumption in China: An urban-rural gap perspective	93
Research on controllable shock wave technology for in-situ development of tar-rich coal	93
Photovoltaic-powered seasonal snow storage-assisted district cooling system: Site suitability analysis and performance assessment	93
Development of a membrane-less microfluidic thermally regenerative ammonia battery	93
Two-stage energy management method of integrated energy system considering pre-transaction behavior of energy service provider and users	93
A novel feature optimization and ensemble learning method for state-of-health prediction of mining lithium-ion batteries	93
Energy management of renewable energy connected electric vehicles charging using Internet of things: Hybrid MRA-SDRN approach	92
Investigating and quantifying the effects of catalyst layer gradients, operating conditions, and their interactions on PEMFC performance through global sensitivity analysis	92
Comparative analysis of combustion, thermodynamic and environmental performance of hydrogen-doping X-type rotary engines using single-ignitor and dual-ignitors under high-altitude condition	92
Determining the reasonable volume required to inject liquid CO2 into a single hole and displace CH4 within the coal seam in bedding boreholes: case study of SangShuPing coal mine	92
Cooking energy use in Bangladesh: Evidence from technology and fuel choice	91
The interplay among COVID-19 economic recovery, behavioural changes, and the European Green Deal: An energy-economic modelling perspective	91