Publications by Lina Bertling Tjernberg
Refereegranskade
Artiklar
[1]
Y. B. Beyene, G. B. Worku and L. Bertling Tjernberg, "On the design and optimization of distributed energy resources for sustainable grid-integrated microgrid in Ethiopia," International journal of hydrogen energy, vol. 48, no. 78, pp. 30282-30298, 2023.
[2]
S. Borenius et al., "Expert-Guided Security Risk Assessment of Evolving Power Grids," Energies, vol. 15, no. 9, pp. 3237, 2022.
[3]
A. Heydari et al., "A Hybrid Intelligent Model for the Condition Monitoring and Diagnostics of Wind Turbines Gearbox," IEEE Access, vol. 9, pp. 89878-89890, 2021.
[4]
A. Heydari et al., "A combined fuzzy gmdh neural network and grey wolf optimization application for wind turbine power production forecasting considering scada data," Energies, vol. 14, no. 12, 2021.
[5]
M. Neshat et al., "A deep learning-based evolutionary model for short-term wind speed forecasting : A case study of the Lillgrund offshore wind farm," Energy Conversion and Management, vol. 236, 2021.
[6]
Y. Cui, P. Bangalore and L. Bertling, "A fault detection framework using RNNs for condition monitoring of wind turbines," Wind Energy, 2021.
[7]
H. Shafique et al., "Behind the Meter Strategies Energy management system with a Swedish case study," IEEE Electrification Magazine, vol. 9, no. 3, pp. 112-119, 2021.
[8]
Y. Li et al., "Investigation on liquid cold plate thermal management system with heat pipes for LiFePO4 battery pack in electric vehicles," Applied Thermal Engineering, vol. 185, 2021.
[9]
M. Neshat et al., "Wind turbine power output prediction using a new hybrid neuro-evolutionary method," Energy, vol. 229, 2021.
[10]
P. Mazidi et al., "Health Condition Model for Wind Turbine Monitoring through Neural Networks and Proportional Hazard Models," Journal of Risk and Reliability, vol. 231, no. 5, 2017.
[11]
P. Mazidi, L. Bertling Tjernberg and M. A. Sanz-Bobi, "Wind Turbine Prognostics and Maintenance Management based on a Hybrid Approach of Neural Networks and Proportional Hazards Model," Journal of Risk and Reliability, vol. 231, no. 2, pp. 121-129, 2017.
[12]
M. Du et al., "A som based anomaly detection method for wind turbines health management through scada data," International Journal of Prognostics and Health Management, vol. 7, no. 4, 2016.
[13]
P. Mazidi, L. Bertling Tjernberg and M. A. Sanz Bobi, "Wind Turbine Prognostics and Maintenance Management based on a Hybrid Approach of Neural Networks and Proportional Hazards Model," Journal of Risk and Reliability, 2016.
[14]
P. Bangalore and L. B. Tjernberg, "An Artificial Neural Network Approach for Early Fault Detection of Gearbox Bearings," IEEE Transactions on Smart Grid, vol. 6, no. 2, pp. 980-987, 2015.
[15]
M. Shafiee et al., "Optimal Redundancy and Maintenance Strategy Decisions for Offshore Wind Power Converters," International Journal of Reliability, Quality and Safety Engineering (IJRQSE), vol. 22, no. 3, pp. 1550015-1-1550015-24, 2015.
[16]
W. Feng et al., "A New Approach for Benefit Evaluation of Multiterminal VSC–HVDC Using A Proposed Mixed AC/DC Optimal Power Flow," IEEE Transactions on Smart Grid, vol. 29, no. 1, pp. 432-443, 2014.
[17]
F. Besnard and L. Bertling, "An approach for condition-based maintenance optimization applied to wind turbine blades," IEEE Transactions on Sustainable Energy, vol. 1, no. 2, pp. 77-83, 2010.
[18]
C. J. Wallnerström, L. Bertling and L. A. Tuan, "Risk and reliability assessment for electrical distribution systems and impacts of regulations with examples from Sweden," International Journal of Systems Assurance Engineering and Management, vol. 1, no. 2, pp. 87-95, 2010.
[19]
T. Lindquist, L. Bertling and R. Eriksson, "Circuit breaker failure data and reliability modelling," IET Generation, Transmission and Distribution, vol. 2, no. 6, pp. 813-820, 2008.
[20]
T. Lindquist and L. Bertling, "Hazard rate estimation for high-voltage contacts using infrared thermography," Proceedings. Annual Reliability and Maintainability Symposium, pp. 233-239, 2008.
[21]
C. J. Wallnerström and L. M. Bertling, "Investigation of the robustness of the Swedish network performance assessment model," IEEE Transactions on Power Systems, vol. 23, no. 2, pp. 773-780, 2008.
[22]
J. Nilsson and L. M. Bertling, "Maintenance management of wind power systems using condition monitoring systems - Life cycle cost analysis for two case studies," IEEE transactions on energy conversion, vol. 22, no. 1, pp. 223-229, 2007.
[23]
P. Hilber et al., "Multiobjective Optimization Applied to Maintenance Policy for Electrical Networks," IEEE Transactions on Power Systems, vol. 22, no. 4, pp. 1675-1682, 2007.
[24]
T. Lindquist, L. Bertling and R. Eriksson, "A method for age modeling of power system components based on experiences from the design process with the purpose of maintenance optimization," Proceedings. Annual Reliability and Maintainability Symposium, pp. 82-88, 2005.
[25]
L. M. Bertling, R. Allan and R. Eriksson, "A reliability-centered asset maintenance method for assessing the impact of maintenance in power distribution systems," IEEE Transactions on Power Systems, vol. 20, no. 1, pp. 75-82, 2005.
[26]
R. Billinton, M. Fotuhi-Firuzabad and L. M. Bertling, "Bibliography on the application of probability methods in power system reliability evaluation 1996-1999," IEEE Transactions on Power Systems, vol. 16, no. 4, pp. 595-602, 2001.
Konferensbidrag
[27]
A. Heydari et al., "A New Combined PV Output Power Forecasting Model Based on Optimized LSTM Network," in 2023 IEEE IAS Global Conference on Emerging Technologies, GlobConET 2023, 2023.
[28]
F. Chen et al., "Medium-Term Wind Power Forecasting based on Dynamic Self-Attention Mechanism," in 2023 IEEE Belgrade PowerTech, PowerTech 2023, 2023.
[29]
Y. B. Beyene, G. B. Worku and L. Bertling Tjernberg, "On Virtual Complex Impedance Droop Control of VSC-Based Islanded Microgrids," in Proceedings of 2023 IEEE PES Innovative Smart Grid Technologies Europe, ISGT EUROPE 2023, 2023.
[30]
A. Dogra and L. Bertling Tjernberg, "Potential Impact of Electric Vehicles Connected to the Grid-A Pre-Study for the Swedish Power System," in Proceedings of 2023 IEEE PES Innovative Smart Grid Technologies Europe, ISGT EUROPE 2023, 2023.
[31]
J. E. U. Cabus, Y. Cui and L. Bertling, "An Anomaly Detection Approach Based on Autoencoders for Condition Monitoring of Wind Turbines," in 2022 17th international conference on probabilistic methods applied to power systems (PMAPS), 2022.
[32]
Y. Cui and L. Bertling Tjernberg, "Fault Diagnostics of Power Transformers Using Autoencoders and Gated Recurrent Units with Applications for Sensor Failures," in 2022 17th International Conference on Probabilistic Methods Applied to Power Systems (PMAPS)., 2022.
[33]
E. Holmgren et al., "MORE ELECTRIC AIRCRAFT (MEA) SCALING ASPECTS AND WEIGHT IMPACT," in 33rd Congress of the International Council of the Aeronautical Sciences, ICAS 2022, 2022, pp. 385-409.
[34]
P. Gopalakrishnan et al., "Peak Demand Shaving Based on Solar and Load Forecasting at Port of Gavle," in 2022 17th International Conference on Probabilistic Methods Applied to Power Systems, PMAPS 2022, 2022.
[35]
H. Shafique et al., "Real-time Operation Model for Energy Management System of Battery Energy Storage System - Case Study : The School of Sinntorp," in 2022 17th International Conference on Probabilistic Methods Applied to Power Systems, PMAPS 2022, 2022.
[36]
L. Tunelid et al., "Simplistic Revenue Based BESS Sizing Tool Developed in Python Using Historical Grid Data," in IEEE PES Innovative Smart Grid Technologies Conference Europe (ISGT Europe), 2022, pp. 1-6.
[37]
Y. Bekele, G. Biru and L. Tjernberg Bertling, "Sustainable Off-grid Systems with Integration of Renewable Generation and Hydrogen-Fuel Cell," in IEEE PES Innovative Smart Grid Technologies Conference Europe, 2022.
[38]
H. Shafique et al., "Energy Management System (EMS) of Battery Energy Storage System (BESS) – Providing Ancillary Services," in 2021 IEEE Madrid PowerTech, PowerTech 2021 - Conference Proceedings, 2021.
[39]
P. Alikhani et al., "Forecasting the Electrical Demand at the Port of Gavle Container Terminal," in 2021 IEEE PES INNOVATIVE SMART GRID TECHNOLOGY EUROPE (ISGT EUROPE 2021), 2021, pp. 806-811.
[40]
P. Alikhani et al., "Forecasting the Electrical Demand at the Port of Gävle Container Terminal," in IEEE PES ISGT EUROPE 2021, 2021, p. 6.
[41]
P. Alikhani et al., "On the Reliability and Life Cycle Cost Analyses of Small-scale Standalone Solar Systems in Rural Areas," in 2021 IEEE Power & Energy Society Innovative Smart Grid Technologies Conference (ISGT), 2021, p. 5.
[42]
Q. Huang et al., "Wind Turbine Health Assessment Framework Based on Power Analysis Using Machine Learning Method," in Proceedings of 2019 IEEE PES Innovative Smart Grid Technologies Europe, ISGT-Europe 2019, 2019.
[43]
Y. Cui, P. Bangalore and L. Bertling Tjernberg, "An Anomaly Detection Approach Using Wavelet Transform and Artificial Neural Networks for Condition Monitoring of Wind Turbines' Gearboxes," in 2018 POWER SYSTEMS COMPUTATION CONFERENCE (PSCC), 2018.
[44]
Y. Cui, P. Bangalore and L. Bertling Tjernberg, "An anomaly detection approach based on machine learning and scada data for condition monitoring of wind turbines," in 2018 International Conference on Probabilistic Methods Applied to Power Systems, PMAPS 2018 - Proceedings, 2018.
[45]
P. Mazidi, L. Bertling and M. A. Sanz-Bobi, "Performance Analysis and Anomaly Detection in Wind Turbines based on Neural Networks and Principal Component Analysis," in 12TH WORKSHOP ON INDUSTRIAL SYSTEMS AND ENERGY TECHNOLOGIES (JOSITE2017), MADRID, SPAIN, 2017.
[46]
P. Mazidi et al., "A Performance and Maintenance Evaluation Framework for Wind Turbines," in International Conference on Probabilistic Methods Applied to Power Systems (PMAPS), Oct. 16-20, 2016 Beijing, China, 2016.
[47]
P. Bangalore et al., "Analysis of SCADA data for early fault detection with application to the maintenance management of wind turbines," in CIGRE Session 46, 2016, pp. 1-10.
[48]
Z. Yuan et al., "Applying High Performance Computing to Probabilistic Convex Optimal Power Flow," in 2016 INTERNATIONAL CONFERENCE ON PROBABILISTIC METHODS APPLIED TO POWER SYSTEMS (PMAPS), 2016.
[49]
C. J. Wallnerström et al., "Framework for System Analyses of Smart Grid Solutions with Examples from the Gotland Case," in 2016 International Conference on Probabilistic Methods Applied to Power Systems (PMAPS), 2016.
[50]
S. Babu et al., "Analyses of Smart Grid Technologies and Solutions from a System Perspective," in Smart Grid Technologies - Asia (ISGT ASIA), 2015 IEEE Innovative, 2015, pp. 1-5.
[51]
Y. Arafat, L. Bertling Tjernberg and P. -. Gustafsson, "Experience from real tests on multiple smart meter switching," in IEEE PES Innovative Smart Grid Technologies Conference Europe, 2015.
[52]
Y. Arafat, L. Bertling Tjernberg and P. -. Gustafsson, "Field test on multiple Smart Meter switching to study the effect on power quality at customers level," in 2015 IEEE Eindhoven PowerTech, PowerTech 2015, 2015.
[53]
D. Steen et al., "Impact assessment of wind power and demand side management on day-ahead market prices," in IEEE PES Innovative Smart Grid Technologies Conference Europe, 2015.
[54]
Y. Arafat, L. Bertling Tjernberg and P.-A. Gustafsson, "On Possibilities of Using Smart Meters for Emergency Grid Management : Analysing the Effect on Power Quality," in 2015 IEEE INNOVATIVE SMART GRID TECHNOLOGIES - ASIA (ISGT ASIA), 2015.
[55]
G. Puglia, P. Bangalore and L. Bertling Tjernberg, "Cost Efficient Maintenance Strategies for Wind Power Systems Using LCC," in International Conference on Probabilistic Methods Applied to Power Systems (PMAPS), 2014.
[56]
P. Bangalore and L. Bertling Tjernberg, "Self Evolving Neural Network Based Algorithm for Fault Prognosis in Wind Turbines : A Case Study," in International Conference on Probabilistic Methods Applied to Power Systems (PMAPS), 2014.
[57]
G. Pinares et al., "Analysis of the dc dynamics of VSC-HVDC systems using a frequency domain approach," in 2013 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC), 2013, p. 6837285.
[58]
C. J. Wallnerström and L. Bertling, "Laws And Regulations Of Swedish Power Distribution Systems 1996-2012 : learning from novel approaches such as less good experiences," in CIRED Workshop 2010 Lyon, 2010.
[59]
C. J. Wallnerström and L. Bertling, "Learning from Experiences of the prior Swedish Electrical Distribution System Regulation : Reference Material when Developing the Future Regulatory Incentives," in Innovative Smart Grid Technologies Conference Europe (ISGT Europe), 2010 IEEE PES, 2010.
[60]
C. J. Wallnerström et al., "Model of Capacity Demand under uncertain Weather," in Proceedings IEEE International Conference on Probabilistic Methods Applied to Power Systems (PMAPS), 2010, pp. 314-318.
[61]
F. Besnard, J. Nilsson and L. Bertling, "On the economic benefits of using condition monitoring systems for maintenance management of wind power systems," in 2010 IEEE 11th International Conference on Probabilistic Methods Applied to Power Systems, PMAPS 2010, 2010, pp. 160-165.
[62]
F. Besnard et al., "An Optimization Framework for Opportunistic Maintenance of Offshore Wind Power System," in 2009 IEEE BUCHAREST POWERTECH, VOLS 1-5, 2009, pp. 2970-2976.
[63]
J. Setréus et al., "Components' Impact on Critical Transfer Section for Risk Based Transmission System Planning," in 2009 IEEE Bucharest PowerTech : Innovative Ideas Toward the Electrical Grid of the Future, 2009, pp. 368-375.
[64]
C. J. Wallnerström and L. Bertling, "Risk Management Applied to Electrical Distribution Systems," in CIRED 2009, Prague, 2009.
[65]
R. Leelaruji et al., "Availability Assessment of the HVDC Converter Transformer System," in Proceedings of the 10th International Conference on Probabilistic Methods Applied to Power Systems, PMAPS 2008, 2008, pp. 575-582.
[66]
J. Setréus and L. Bertling, "Introduction to HVDC Technology for Reliable Electrical Power Systems," in Proceedings of the 10th International Conference on Probabilistic Methods Applied to Power Systems, PMAPS 2008, 2008, pp. 560-567.
[67]
P. Hilber and L. Bertling, "Multiobjective Maintenance Policy for a Distribution System an Application Study," in 10th International Conference On Probabilistic Methods Applied To Power Systems, 2008, pp. 229-234.
[68]
C. J. Wallnerström et al., "Review of the Risk Management at a Distribution System Operator," in 2008 10TH INTERNATIONAL CONFERENCE ON PROBABILISTIC METHODS APPLIED TO POWER SYSTEMS, 2008, pp. 90-97.
[69]
T. Lindquist and L. Bertling, "A method for calculating disconnector contact availability as a function of thermography inspection intervals and load current," in CIGRE Symposium Osaka 2007 : System Development and Asset Management under Restructuring, 2007.
[70]
P. Hilber and L. Bertling, "Component Reliability Importance Indices for Electrical Networks," in 2007 CONFERENCE PROCEEDINGS IPEC, VOLS 1-3, 2007, pp. 257-263.
[71]
J. Ribrant and L. M. Bertling, "Survey of failures in wind power systems with focus on Swedish wind power plants during 1997-2005," in 2007 IEEE POWER ENGINEERING SOCIETY GENERAL MEETING, 2007, pp. 3896-3903.
[72]
A. A. Chowdhury, L. Bertling and B. P. Glover, "Causal and seasonal analysis of bulk transmission lineforced outages using the MAPP outage database," in 2006 INTERNATIONAL CONFERENCE ON PROBABILISTIC METHODS APPLIED TO POWER SYSTEMS, VOLS 1 AND 2, 2006, pp. 819-825.
[73]
A. A. Chowdhury, L. M. Bertling and D. E. Custer, "Determining distribution substation transformer optimal loadings using a reliability cost-benefit approach," in 2006 International Conference on Probabilistic Methods Applied to Power Systems, Vols 1 and 2, 2006, pp. 1201-1209.
[74]
A. A. Chowdhury and L. Bertling, "Distribution system in-depth causal reliability assessment," in 2006 International Conference on Probabilistic Methods Applied to Power Systems, Vols 1 and 2, 2006, pp. 805-812.
[75]
P. Hilber, L. Bertling and B. Hällgren, "Effects of Correlation between Failures and Power Consumption on Customer Interruption Cost," in 2006 International Conference on Probabilistic Methods Applied to Power Systems, Vols 1 and 2 : 9th International Conference on Probabilistic Methods Applied to Power Systems. KTH, Stockholm, SWEDEN. JUN 11-15, 2006, 2006, pp. 1120-1123.
[76]
A. A. Chowdhury et al., "Monte Carlo simulation model for multi-area generation reliability evaluation," in 2006 International Conference on Probabilistic Methods Applied to Power Systems, Vols 1 and 2, 2006, pp. 1216-1225.
[77]
P. Hilber and L. Bertling, "A Method for Extracting Reliability Importance Indices from Reliability Simulations of Electrical Networks," in 15th Power Systems Computation Conference, PSCC 2005, 2005.
[78]
L. M. Bertling, R. Allan and R. Eriksson, "A reliability-centred asset maintenance method for assessing the impact of maintenance in power distribution systems," in 2005 IEEE Power Engineering Society General Meeting, 2005, pp. 2649-2649.
[79]
T. Lindquist, L. Bertling and R. Eriksson, "Estimation of disconnector contact condition for modelling the effect of maintenance and ageing," in 2005 IEEE Russia Power Tech, PowerTech, 2005.
[80]
L. Bertling, M. B. Larsson and C. J. Wallnerström, "Evaluation of the Customer Value of Component Redundancy in Electrical Distribution Systems," in Power Tech, 2005 IEEE Russia, 2005, pp. 1-8.
[81]
L. M. Bertling, "On evaluation of RCM for maintenance management of electric power systems," in 2005 IEEE POWER ENGINEERING SOCIETY GENERAL MEETING, 2005, pp. 2638-2640.
[82]
P. Hilber, B. Hällgren and L. Bertling, "Optimizing the replacement of overhead lines in rural distribution systems with respect to reliability and customer value," in Eighteenth International Conference and Exhibition on Electricity Distribution, CIRED 2005, 2005, pp. 127-131.
[83]
T. Lindquist, L. Bertling and R. Eriksson, "A feasibility study for probabilistic modeling of aging in circuit breakers for maintenance optimization," in 2004 INTERNATIONAL CONFERENCE ON PROBABILISTIC METHODS APPLIED TO POWER SYSTEMS, 2004, pp. 1020-1025.
[84]
J. Endrenyi et al., "Comparison of two methods for evaluating the effects of maintenance on component and system reliability," in 2004 International Conference on Probabilistic Methods Applied to Power Systems, 2004, pp. 307-312.
[85]
L. Bertling, "Impact of maintenance on cable failure rates," in 2004 IEEE POWER ENGINEERING SOCIETY GENERAL MEETING, VOLS 1 AND 2, 2004, pp. 704-704.
[86]
P. Hilber and L. Bertling, "Monetary Importance of Component Reliability in Electrical Networks for Maintenance Optimization," in 8th International Conference on Probabilistic Methods Applied to Power Systems : Iowa State Univ, Ames, IA, SEP 12-16, 2004, 2004, pp. 150-155.
[87]
R. Eriksson, T. Lindquist and L. Bertling, "Reliability modelling of aged XLPE cables," in Nordic Insulation Symposium (Nord-Is), 2003, pp. 216-224.
Kapitel i böcker
[88]
P. Balram, L. A. Tuan and L. Bertling Tjernberg, "Centralized charging control of plug-in electric vehicles and effects on day-ahead electricity market price," in Plug In Electric Vehicles in Smart Grids, : Springer, 2015, pp. 267-299.
Icke refereegranskade
Artiklar
[89]
S. Bahramirad et al., "Special Section on Asset Management in Smart Grid," IEEE Transactions on Smart Grid, vol. 6, no. 2, pp. 953-954, 2015.
Konferensbidrag
[90]
L. Bertling and S. Uhrig, "Lifetime Extension Options for Electrical Equipment," in IET Conference Proceedings, 2023, pp. 3185-3189.
[91]
E. Holmgren et al., "More Electric Aircraft (MEA) : Scaling Aspects and Weight Impact," in ICAS, Proceedings, 33th Congress of the International Council of the Aeronautical Sciences, Stockholm, Sweden, 2022.
[92]
A. Johansson, M. Yildiz and L. Bertling, "More Electric Airplane : case study Stockholm – Copenhagen," in ICAS Proceedings, 33th Congress of the International Council of the Aeronautical Sciences, Stockholm, Sweden, 2022, 2022, pp. 1610-1628.
[93]
P. Mazidi, L. Bertling Tjernberg and M. A. Sanz-Bobi, "Anomaly Detection and Performance Analysis in Wind Turbines through Neural Networks," in International Workshop on Life-Cycle Costing of Offshore Wind Turbines and Farms, 2015.
[94]
J. Setréus, C. J. Wallnerström and L. Bertling, "A Comparative Study of Regulation Policies for Interruption of Supply of Electrical Distribution Systems in Sweden and UK," in 19th International Conference on Electricity Distribution (CIRED), 2007, pp. 1-4.
[95]
C. J. Wallnerström and L. Bertling, "A Sensitivity Study of the Swedish Network Performance Assessment Model Investigating the Effects of Changes in Input Data," in 19th International Conference on Electricity Distribution (CIRED), 2007, pp. 1-4.
[96]
A. A. Chowdhury, L. M. Bertling and B. P. Glover, "Causal and seasonal analysis of bulk transmission line forced outages using the MAPP outage database," in 2006 International Conference on Probabilistic Methods Applied to Power Systems, 2006, pp. 847-853.
Kapitel i böcker
[97]
C. J. Wallnerström and L. Bertling, "Analysis of the future power systems’s ability to enable sustainable energy-Using the case system of Smart Grid Gotland," in Application of Smart Grid Technologies : Case Studies in Saving Electricity in Different Parts of the World, : Elsevier BV, 2018, pp. 373-393.
[98]
P. Bangalore and L. Bertling Tjernberg, "Condition Monitoring and Asset Management in the Smart Grid," in Condition Monitoring and Asset Management in the Smart Grid, : John Wiley & Sons, 2016, pp. 1-13.
Avhandlingar
[99]
L. Bertling, "On reliability assessment of distribution systems and reliability centred maintenance," Licentiate thesis Stockholm : KTH, Trita-EES, 99-02, 1999.
Rapporter
[100]
C. J. Wallnerström et al., "Analys av smartaelnätsteknologier inom kategorin elnätslösningar," KTH Royal Institute of Technology, TRITA-EE, 2014:036, 2014.
[101]
L. Bertling et al., "RADPOW development and documentation," KTH Royal Institute of Technology, TRITA-EE 2007:047, 2008.
[102]
L. Bertling, M. B. Larsson and C. J. Wallnerström, "Review of the Swedish Network Performance Assessment Model," , 2008.
[103]
L. Bertling and C. J. Wallnerström, "Nätnyttomodellens tillförlitlighet med avseende på små förändringar i indata," , 2006.
[104]
C. J. Wallnerström and L. Bertling, "Känslighetsanalys av Nätnyttomodellens indata : En analys av 2005 års version av Nätnyttomodellen och dess parametrar för autentiska indata," , 2005.
Övriga
[105]
Senaste synkning med DiVA:
2024-04-21 04:08:35