Publikationer

Artiklar i tidskrifter Doktorsavhandlingar Kapitel i böcker, del av antologier Konferensbidrag Licentiatavhandlingar Rapporter

Artiklar i tidskrifter

Nazar Ul Islam, M. , Cheng, P. & Oelmann, B. (2015). High performance reference setup for characterization and calibration of low-range differential pressure sensors. IEEE Transactions on Instrumentation and Measurement, vol. 64: 1, ss. 154-162.

Imran, M. , Shahzad, K. , Ahmad, N. , O'Nils, M. , Lawal, N. & Oelmann, B. (2014). Energy Efficient SRAM FPGA based Wireless Vision Sensor Node: SENTIOF‐CAM. IEEE transactions on circuits and systems for video technology (Print), vol. 24: 12, ss. 2132-2143.

Mustafa, M. S. , Cheng, P. & Oelmann, B. (2014). Stator-Free Low Angular Speed Sensor Based on a MEMS Gyroscope. IEEE Transactions on Instrumentation and Measurement, vol. 63: 11, ss. 2591-2598.

Bader, S. , Ma, X. & Oelmann, B. (2014). On the Modeling of Solar-Powered Wireless Sensor Nodes. Journal of Sensor and Actuator Networks, vol. 3: 3, ss. 207-223.

Shahzad, K. , Cheng, P. & Oelmann, B. (2013). Architecture exploration for a high-performance and low-power wireless vibration analyzer. IEEE Sensors Journal, vol. 13: 2, ss. 670-682.

Cheng, P. , Yang, Y. & Oelmann, B. (2012). Design and Implementation of a Stator-Free RPM Sensor Prototype Based on MEMS Accelerometers. IEEE Transactions on Instrumentation and Measurement, vol. 61: 3, ss. 775-785.

Cheng, P. , Sobh, M. & Oelmann, B. (2012). Contactless Rotor RPM Measurement Using Laser Mouse Sensors. IEEE Transactions on Instrumentation and Measurement, vol. 61: 3, ss. 740-748.

Thim, J. , Norlin, B. , O'Nils, M. , Abdalla, S. & Oelmann, B. (2011). Realizing increased sub-pixel spatial resolution in X-ray imaging using displaced multiple images. Nuclear Instruments and Methods in Physics Research Section A, vol. 633: Suppl 1, ss. S247-S249.

Thim, J. , Reza, S. , Nawaz, K. , Norlin, B. , O´Nils, M. & Oelmann, B. (2011). Suitable Post Processing Algorithms for X-Ray Imaging using Oversampled Displaced Multiple Images. Journal of Instrumentation, vol. 6: 2, ss. Art. no. C02001

Cheng, P. , Yang, Y. & Oelmann, B. (2011). Stator-free RPM Sensor Using Accelerometers - A Statistical Performance Simulation by Monte Carlo Method. IEEE Sensors Journal, vol. 11: 12, ss. 3368-3376.

Cheng, P. , Oelmann, B. & Linnarsson, F. (2011). A Local Positioning System for Loader Cranes Based on Wireless Sensors-A Feasibility Study. IEEE Transactions on Instrumentation and Measurement, vol. 60: 8, ss. 2881-2893.

Bader, S. & Oelmann, B. (2011). Durable Solar Energy Harvesting from Limited Ambient Energy Income. International Journal on Advances in Networks and Services, vol. 4: 1&2, ss. 66-80.

Cheng, P. & Oelmann, B. (2010). Joint-angle Measurement Using Accelerometers and Gyroscopes : A Survey. IEEE Transactions on Instrumentation and Measurement, vol. 59: 2, ss. 404-414.

O'Nils, M. , Thim, J. , Norlin, B. & Oelmann, B. (2009). Threshold Modulation for Continuous Energy Resolution with Two Channels per Pixel in a Photon Counting X-ray Image Detector. Nuclear Instruments and Methods in Physics Research Section A, vol. 607: 1, ss. 236-239.

Oelmann, B. & Cao, C. (2008). Low-power state encoding for partitioned FSMs with mixed synchronous/asynchronous state memory. Integration, vol. 41: 1, ss. 123-134.

Aunet, S. , Oelmann, B. , Norseng, P. A. & Berg, Y. (2008). Real-time reconfigurable subthreshold CMOS perceptron. IEEE Transactions on Neural Networks, vol. 19: 4, ss. 645-657.

Lundgren, J. , Abdalla, S. , O'Nils, M. & Oelmann, B. (2007). Power Distribution and Substrate Noise Coupling Investigations on the Behavioral Level for Photon Counting Imaging Readout Circuits. Nuclear Instruments and Methods in Physics Research Section A, vol. 576: 1, ss. 113-117.

Lundgren, J. , O'Nils, M. , Oelmann, B. , Norlin, B. & Abdalla, S. (2007). An Area Efficient Readout Architecture for Photon Counting Color Imaging. Nuclear Instruments and Methods in Physics Research Section A, vol. 576: 1, ss. 132-136.

Lundgren, J. , Abdalla, S. , O'Nils, M. & Oelmann, B. (2006). Evaluation of Mixed-Signal Noise Effects in Photon Counting X-Ray Image Sensor Readout Circuits. Nuclear Instruments and Methods in Physics Research Section A, vol. 563: 1, ss. 88-91.

Cao, C. , O'Nils, M. & Oelmann, B. (2006). Synthesis tool for low-power finite-state machines with mixed synchronous/asynchronous state memory. IEE Proceedings - Computers and digital Techniques, vol. 153: 4, ss. 243-248.

Xue, S. & Oelmann, B. (2006). Unary Prefixed Huffman Coding for a Group of Quantized Generalized Gaussian Sources. IEEE Transactions on Communications, vol. 54: 7, ss. 1164-1169.

Xue, S. & Oelmann, B. (2005). Unary-Prefixed Encoding of the Lengths of Consecutive Zeros in a Bit Vector. Electronics Letters, vol. 41: 6, ss. 346-347.

Xue, S. , Xu, Y. & Oelmann, B. (2003). Hybrid Golomb codes for a group of quantised GG sources. IEE Proceedings - Vision Image and Signal Processing, vol. 150: 4, ss. 256-260.

O'Nils, M. , Abdalla, M. & Oelmann, B. (2002). Low Digital Interference Counter for Photon Counting Pixel Detectors. Nuclear Instruments and Methods in Physics Research, Section A, vol. 487: 3, ss. 323-330.

Oelmann, B. , Abdalla, M. & O'Nils, M. (2002). Robust window discriminator for photon-counting pixel detectors. IEE Proceedings - Optoelectronics, vol. 149: 2, ss. 65-69.

Oelmann, B. , Tammenmäe, K. , Kruus, M. & O'Nils, M. (2001). Automatic FSM synthesis for low-power mixed synchronous/asynchronous implementation. VLSI Design, vol. 12: 2, ss. 167-186.

Oelmann, B. , Abdalla, S. & O'Nils, M. (2001). All-Digital Window Discriminator for Photon Counting Pixel Detectors. Electronics Letters, vol. 37: 6, ss. 373-374.

Shahzad, K. & Oelmann, B. (). Development of an FPGA based high-performance and low-power wireless embedded platform for wireless monitoring applications. Ad Hoc & Sensor Wireless Networks,

Doktorsavhandlingar

Oelmann, B. (2000). Asynchronous and Mixed Synchronous/Asynchronous Design Techniques for Low Power. Diss. , 2000 (Trita-ESD : 0006)

Kapitel i böcker, del av antologier

Oelmann, B. & Cao, C. (2007). A Mixed Synchronous/Asynchronous Design Approach for Fine-Grained Dynamic. I Brain Inspired Nano Architectures 2007. World Scientific.

Konferensbidrag

Shahzad, K. & Oelmann, B. (2014). Investigating Energy Consumption of an SRAM-based FPGA for Duty-Cycle Applications. I Advances in parallel computing.. S. 548--559.

Shahzad, K. & Oelmann, B. (2014). A comparative study of in-sensor processing vs. raw data transmission using ZigBee, BLE and Wi-Fi for data intensive monitoring applications. I 2014 11th International Symposium on Wireless Communications Systems, ISWCS 2014 - Proceedings.. S. 519--524.

Bader, S. , Krämer, M. & Oelmann, B. (2013). A Domain-Specific Platform for Research in Environmental Wireless Sensor Networks. I SENSORCOMM 2013, The Seventh International Conference on Sensor Technologies and Applications.. S. 200--207.

Bader, S. & Oelmann, B. (2013). Short-term energy storage for wireless sensor networks using solar energy harvesting. I Networking, Sensing and Control (ICNSC), 2013 10th IEEE International Conference on. (IEEE International Conference on Networking Sensing and Control). S. 71--76.

Krämer, M. , Bader, S. & Oelmann, B. (2013). Implementing Wireless Sensor Network applications using hierarchical finite state machines. I Networking, Sensing and Control (ICNSC), 2013 10th IEEE International Conference on. (IEEE International Conference on Networking Sensing and Control). S. 124--129.

Bader, S. & Oelmann, B. (2013). Concealing the complexity of node programming in wireless sensor networks. I Proceedings of the 2013 IEEE 8th International Conference on Intelligent Sensors, Sensor Networks and Information Processing: Sensing the Future, ISSNIP 2013.. S. 177--182.

Shahzad, K. , Cheng, P. & Oelmann, B. (2013). SENTIOF : An FPGA based high-performance and low-power wireless embedded platform. I 2013 Federated Conference on Computer Science and Information Systems, FedCSIS 2013 : Proceedings.. S. 901--906.

Shahzad, K. & Oelmann, B. (2013). An FPGA-Based High-Performance Wireless Vibration Analyzer. I NORCHIP 2013.. S. Art. no. 6702038-

Bader, S. , Oelmann, B. & Brunig, M. (2012). Challenges for RF two-way time-of-flight ranging in wireless sensor networks. I Proceedings - Conference on Local Computer Networks, LCN. (Proceedings - Conference on Local Computer Networks, LCN). S. 908--916.

Ahmad, N. , Lawal, N. , O'Nils, M. , Oelmann, B. , Imran, M. & Khursheed, K. (2011). Model and placement optimization of a sky surveillance visual sensor network. I Proceedings - 2011 International Conference on Broadband and Wireless Computing, Communication and Applications, BWCCA 2011.. S. 357--362.

Bader, S. , Anneken, M. , Goldbeck, M. & Oelmann, B. (2011). SAQnet: Experiences from the Design of an Air Pollution Monitoring System Based on Off-the-Shelf Equipment. I Proceedings of the 2011 7th International Conference on Intelligent Sensors, Sensor Networks and Information Processing, ISSNIP 2011.. S. 223--228.

Bader, S. , Schölzel, T. & Oelmann, B. (2010). A Method for Dimensioning Micro-Scale Solar Energy HarvestingSystems Based on Energy Level Simulations. I Proceedings - IEEE/IFIP International Conference on Embedded and Ubiquitous Computing, EUC 2010.. S. 372--379.

Wang, X. , Rödjegård, H. , Oelmann, B. , Martin, H. & Larsson, B. (2010). High performance CO₂ measurement based on pressure modulation. I Proceedings of 24th Eurosensors Conference. (Procedia Engineering). S. 1208--1211.

Bader, S. & Oelmann, B. (2010). Enabling battery-less wireless sensor operation using solar energy harvesting at locations with limited solar radiation. I Proceedings - 4th International Conference on Sensor Technologies and Applications, SENSORCOMM 2010.. S. 602--608.

Thim, J. , Norlin, B. , O'Nils, M. , Abdalla, S. & Oelmann, B. (2009). Realizing increased sub-pixel spatial resolution in X-ray imaging using displaced multiple images. I 11th International Workshop on Radiation Imaging Detectors.

Bader, S. & Oelmann, B. (2009). Adaptive synchronization for duty-cycling in environmental wireless sensor networks. I ISSNIP 2009 - Proceedings of 2009 5th International Conference on Intelligent Sensors, Sensor Networks and Information Processing.. S. 49--54.

Linnarsson, F. , Cheng, P. & Oelmann, B. (2008). A Power Aware MAC protocol for Wireless Closed Loop Control System in Loader Cranes. I 2008 IEEE INTERNATIONAL SYMPOSIUM ON INDUSTRIAL ELECTRONICS, VOLS 1-5. New York : . S. 1806--1811.

Abdalla, S. , Oelmann, B. , O'Nils, M. & Thim [Lundgren], J. (2007). Architecture and Circuit Design for Color X-Ray Pixal Array Detector Read-Out Electronics. I Proceedings of the IEEE Norchip Conference 2007. New York : . S. 271--276.

Alfredsson, J. , Aunet, S. & Oelmann, B. (2007). Small Fan-in Floating-gate Circuits with Application to an Improved Adder Structure. I 20TH INTERNATIONAL CONFERENCE ON VLSI DESIGN, PROCEEDINGS - TECHNOLOGY CHALLENGES IN THE NANOELECTRONICS ERA. (International Conference on VLSI Design, Proceedings). S. 314--317.

Cheng, P. , Linnarsson, F. & Oelmann, B. (2007). Joint Angular Sensor Based on Distributed Biaxial MEMS Accelerometers. I IECON 2007: 33RD ANNUAL CONFERENCE OF THE IEEE INDUSTRIAL ELECTRONICS SOCIETY, VOLS 1-3, CONFERENCE PROCEEDINGS. New York : (IEEE Industrial Electronics Society). S. 2242--2247.

Unander, T. , Nilsson, H. & Oelmann, B. (2007). Printed touch sensor for interactive packaging and display. I Polytronic 2007 : the 6th International IEEE Conference on Polymers and Adhesives in Microelectronics and Photonics.. S. 12--17.

Cao, C. & Oelmann, B. (2007). The Analysis of Power-Related Characteristics of FSM Benchmarks. I 2007 50TH MIDWEST SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOLS 1-3. New York : (Midwest Symposium on Circuits and Systems Conference Proceedings). S. 787--790.

Linnarsson, F. , Cheng, P. & Oelmann, B. (2007). Analysis of the IEEE 802.15.4 Standard for a Wireless Closed Loop Control System for Heavy Duty Cranes. I 2007 INTERNATIONAL SYMPOSIUM ON INDUSTRIAL EMBEDDED SYSTEMS - SIES'2007.. S. 164--169.

Alfredsson, J. & Oelmann, B. (2006). Influence of Refresh Circuits Connected to Low Power Digital Quasi-Floating gate Designs. I 2006 13TH IEEE INTERNATIONAL CONFERENCE ON ELECTRONICS, CIRCUITS AND SYSTEMS, VOLS 1-3.. S. 1296--1299.

Cao, C. & Oelmann, B. (2006). Area-Power Trade-Off in FSM Partitioning. I International conference on signals and electronic systems. Conference proceedings, 17-20 sept. 2006, Lodz, Poland.. S. 349--352.

Alfredsson, J. & Oelmann, B. (2006). Capacitance Selection for Digital Floating Gate Circuits Operating in Subthreshold. I 2006 IEEE INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOLS 1-11, PROCEEDINGS. (IEEE INTERNATIONAL SYMP ON CIRCUITS AND SYSTEMS). S. 4341--4344.

Linnarsson, F. , Cheng, P. & Oelmann, B. (2006). SENTIO: A. Hardware Platform for Rapid Prototyping of Wireless Sensor Networks. I IECON 2006 - 32ND ANNUAL CONFERENCE ON IEEE INDUSTRIAL ELECTRONICS, VOLS 1-11. (IEEE Industrial Electronics Society). S. 2243--2247.

Abdalla, S. , Nilsson, H. & Oelmann, B. (2005). Circuit Implementation of Mechanism for Charge-Sharing Suppression for Photon-Counting Pixel Arrays. I Norchip 2005, Proceedings.. S. 137--140.

O'Nils, M. , Oelmann, B. , Bertilsson, K. , Nilsson, H. & Thungström, G. (2005). A Project Based Master's Program for SoF/SoC based Sensor Systems. I Proceedings of the European Conference on Circuit Theory and Design.

Alfredsson, J. , Aunet, S. & Oelmann, B. (2005). Basic Speed and Power Properties of Digital Floating-gate Circuits Operating in Subthreshold. I Proceedings of IFIP VLSI-SOC 2005 : International Conference on Very Large Scale Integration.. S. 229--232.

Mårtensson, P. , Persson, J. , Xue, S. & Oelmann, B. (2005). Efficient Decoding of Variable Length Endoded Image Data on the Nios II Soft-Core Processor. I Proceedings of the International Workshop on Applied Reconfigurable Computing, Algarve, Portugal, February 2005.

Oelmann, B. , Linnarsson, F. , Aunet, S. & Berg, Y. (2004). Experimental Setup for UV-Programming of Floating-Gate MOS Circuits. I Proceedings of IEEE International Conference on Signals and Electronic Systems.

Aunet, S. , Oelmann, B. , Abdalla, S. & Berg, Y. (2004). Reconfigurable Subthreshold CMOS Perceptron. I IEEE International Joint Conference on Neural Networks 2004.

Cao, C. & Oelmann, B. (2004). Mixed Synchronous/Asynchronous State Memory for Low Power FSM Design. I Proceedings of EUROMICRO Symposium on Digital System Design.. S. 363--370.

Oelmann, B. & O'Nils, M. (2004). A Course in Basic Digital Electronics for a Distance Educational Programme. I Proceedings of IEEE International Conference on Signals and Electronic Systems.

Alfredsson, J. & Oelmann, B. (2004). Trading Speed and Power for Reduced Substrate Noise from Digital CMOS Circuits. I Proceedings of IEEE International Conference on Signals and Electronic Systems. Poznan, Poland :

Cao, C. , O'Nils, M. & Oelmann, B. (2004). A Tool for Low-Power Synthesis of FSMs with Mixed Synchronous/Asynchronous State Memory. I 22ND NORCHIP CONFERENCE, PROCEEDINGS.. S. 199--202.

Aunet, S. & Oelmann, B. (2004). 200 mV Full Adder Based on a Reconfigurable CMOS Perceptron. I Proceedings of IEEE International Conference on Signals and Electronic Systems.

Aunet, S. , Oelmann, B. , Lande, T. & Yngvar, B. (2004). Multifunction Subthreshold Gate used for a Low Power Full Adder. I Proceedings of the IEEE Norchip Conference.

Lundgren, J. , Oelmann, B. , Ytterdal, T. , Eriksson, P. , Abdalla, M. & O'Nils, M. (2003). A power-line noise coupling estimation methodology for architectural exploration of mixed-signal systems. I Proceedings of the Southwest Symposium on Mixed-Signa Design.. S. 133--137.

O´Nils, M. , Lundgren, J. & Oelmann, B. (2003). A SystemC Extension for Behavioral Level Quantification of Noise-Coupling in Mixed-Signal Systems. I PROCEEDINGS OF THE 2003 IEEE INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOL III - GENERAL & NONLINEAR CIRCUITS AND SYSTEMS Vol 3.. S. 898--901.

Linnarsson, F. , Aunet, S. & Oelmann, B. (2003). A Static Single-Phase D-latch for UV-Programmable Floating-Gate MOSFET Circuits. .

Lundgren, J. , Oelmann, B. , Ytterdal, T. , Eriksson, P. , Abdalla, M. & O´Nils, M. (2003). Behavioral Simulation of Power Line Noise Coupling in Mixed-Signal Systems using SystemC. I ISVLSI 2003: IEEE COMPUTER SOCIETY ANNUAL SYMPOSIUM ON VLSI, PROCEEDINGS - NEW TRENDS AND TECHNOLOGIES FOR VLSI SYSTEMS DESIGN.. S. 275--277.

Xue, S. & Oelmann, B. (2003). Efficient VLSI Implementation of a VLC Decoder for Universal Variable Length Code using Alternating Coding. I ISVLSI 2003: IEEE COMPUTER SOCIETY ANNUAL SYMPOSIUM ON VLSI, PROCEEDINGS - NEW TRENDS AND TECHNOLOGIES FOR VLSI SYSTEMS DESIGN.. S. 207--208.

Xue, S. & Oelmann, B. (2003). Efficient VLSI Implementation of a VLC Decoder for Golomb-Rice Code using Alternating Coding. I IEEE Norchip´03, Riga, Latvia, November 2003.

Xue, S. & Oelmann, B. (2003). Parallel Variable-length Decoder Architecture for Alternated Coded GR-Codes. I IEEE Norchip´03, Riga, latvia, november, 2003.

Xue, S. & Oelmann, B. (2003). Error Resilient coding of DCT coefficients using alternating coding of UVLC. I Norsig, Bergen, Norway,  October 2003.

Xue, S. & Oelmann, B. (2003). A Coding Method for UVLC Targeting Efficient Decoder Architecture. I Proceedings of the 3rd IEEE Internatioal Symposium on Image and Signal Processing and Analysis, Rome, Italy, September, 2003.. S. 428--433.

Xue, S. & Oelmann, B. (2003). Alternating Coding for Universal Variable Length Code. I Procceedings of the IEEE International Conference on Image Processing, Barcelona, Spain, September, 2003.. S. 477--480.

Xue, S. & Oelmann, B. (2001). Comparative study of low-voltage performance of standard-cell flip-flops. I ICECS 2001 : 8TH IEEE INTERNATIONAL CONFERENCE ON ELECTRONICS, CIRCUITS AND SYSTEMS, VOLS I-III, CONFERENCE PROCEEDINGS. New York : . S. 953--957.

O'Nils, M. & Oelmann, B. (2000). Using CoWare in a Course on Design of Embedded HW/SW System. I Proceedings of the 18th IEEE Norchip Conference.

Norell, H. , O'Nils, M. & Oelmann, B. (2000). Requirement Analysis of Reconfigurable Hardware Prototyping Platforms for Development of Real-Time Video Applications. I Proceedings of 18th IEEE Norchip Conference.

Norell, H. , Oelmann, B. & Xu, Y. (2000). Spatio-Temporal Noise Reduction algorithm targeting Real-Time Video Processing. I Proceedings of IEEE International Symposium on Information Theory and Its Applications 2000.

Norell, H. , Oelmann, B. & Xu, Y. (2000). Spatio-Temporal Noise Reduction ASIC for Real-Time Noise Reduction ASIC Processing. I Proceedings of 2000 IEEE Nordic Signal Processing Symposium.

Oelmann, B. , Norell, H. , Andersson, R. & Xu, Y. (1999). Design of Real-Time Signal Processing ASIC for Noise Reduction In Moving Video Images. I Proceedings of the 17th IEEE Norchip conference.

Oelmann, B. & O'Nils, M. (1999). LIFS: A Tool for Low-Power Implementation of FSMs. I Proceedings of the 17th IEEE Norchip Conference.

Oelmann, B. & O'Nils, M. (1999). Asynchronous Control of Low-Power Gated-Clock Finite-State Machines. I Proceedings of IEEE International Conference on Electronics, Circuits and Systems.

Oelmann, B. & O'Nils, M. (1999). A Low Power Hand-Over Mechanism for Gated-Clock FSMs. I Proceedings of the European Conference on Circuit Theory and Design.

Pasanen, J. & Oelmann, B. (1999). Locally clocked AFSMs using dynamic latch implementation. I Electronics, Circuits and Systems, 1999. Proceedings of ICECS '99. The 6th IEEE International Conference on : Vol 3.. S. 1643--1646.

Oelmann, B. & Tenhunen, H. (1996). Micropipeline DSP-ASIC for DS-SS receiver. .

Oelmann, B. , Martijn, H. & Tenhunen, H. (1996). An asynchronous implementation of a DS-SS radio receiver. .

Oelmann, B. & Tenhunen, H. (1996). A system level performance model for asynchronous micropipeline circuits. .

Oelmann, B. , Olsson, H. , Kerek, D. & Tenhunen, H. (1996). Differential PSK detector design for direct sequence spread spectrum radio. .

Oelmann, B. & Tenhunen, H. (1995). Comparison of self-timed and synchronous high-speed VLSI/ULSI circuits using system level performance modelling. .

Oelmann, B. , Martijn, H. & Tenhunen, H. (1995). Design of an asynchronous macro-cell library. .

Oelmann, B. , Martijn, H. & Tenhunen, H. (1995). Design of an asynchronous direct sequence spread spectrum digital radio receiver. .

Shahzad, K. & Oelmann, B. (). Quantitative Evaluation of an FPGA based Wireless Vibration Monitoring System in relation to Different Sampling Rates. .

Licentiatavhandlingar

Oelmann, B. (1996). Design and Performance Evaluation of Asynchronous Micropipeline Circuits for Digital Radio. Lic.-avh. , 1996 (Trita-ESD : 9608)

Rapporter

Oelmann, B. , O'Nils, M. , Tammemäe, K. , Kruus, M. & Tenhunen, H. (2000). Automatic FSM synthesis for low-power mixed synchronous/asynchronous implementation.