232 research outputs found
Constrained Codes for Joint Energy and Information Transfer
In various wireless systems, such as sensor RFID networks and body area
networks with implantable devices, the transmitted signals are simultaneously
used both for information transmission and for energy transfer. In order to
satisfy the conflicting requirements on information and energy transfer, this
paper proposes the use of constrained run-length limited (RLL) codes in lieu of
conventional unconstrained (i.e., random-like) capacity-achieving codes. The
receiver's energy utilization requirements are modeled stochastically, and
constraints are imposed on the probabilities of battery underflow and overflow
at the receiver. It is demonstrated that the codewords' structure afforded by
the use of constrained codes enables the transmission strategy to be better
adjusted to the receiver's energy utilization pattern, as compared to classical
unstructured codes. As a result, constrained codes allow a wider range of
trade-offs between the rate of information transmission and the performance of
energy transfer to be achieved.Comment: 27 pages, 14 figures, Submitted Submitted in IEEE Transactions on
Communication
Interactive Joint Transfer of Energy and Information
In some communication networks, such as passive RFID systems, the energy used
to transfer information between a sender and a recipient can be reused for
successive communication tasks. In fact, from known results in physics, any
system that exchanges information via the transfer of given physical resources,
such as radio waves, particles and qubits, can conceivably reuse, at least
part, of the received resources. This paper aims at illustrating some of the
new challenges that arise in the design of communication networks in which the
signals exchanged by the nodes carry both information and energy. To this end,
a baseline two-way communication system is considered in which two nodes
communicate in an interactive fashion. In the system, a node can either send an
"on" symbol (or "1"), which costs one unit of energy, or an "off" signal (or
"0"), which does not require any energy expenditure. Upon reception of a "1"
signal, the recipient node "harvests", with some probability, the energy
contained in the signal and stores it for future communication tasks. Inner and
outer bounds on the achievable rates are derived. Numerical results demonstrate
the effectiveness of the proposed strategies and illustrate some key design
insights.Comment: 29 pages, 11 figures, Submitted in IEEE Transactions on
Communications. arXiv admin note: substantial text overlap with
arXiv:1204.192
Scalable Deep Traffic Flow Neural Networks for Urban Traffic Congestion Prediction
Tracking congestion throughout the network road is a critical component of
Intelligent transportation network management systems. Understanding how the
traffic flows and short-term prediction of congestion occurrence due to
rush-hour or incidents can be beneficial to such systems to effectively manage
and direct the traffic to the most appropriate detours. Many of the current
traffic flow prediction systems are designed by utilizing a central processing
component where the prediction is carried out through aggregation of the
information gathered from all measuring stations. However, centralized systems
are not scalable and fail provide real-time feedback to the system whereas in a
decentralized scheme, each node is responsible to predict its own short-term
congestion based on the local current measurements in neighboring nodes.
We propose a decentralized deep learning-based method where each node
accurately predicts its own congestion state in real-time based on the
congestion state of the neighboring stations. Moreover, historical data from
the deployment site is not required, which makes the proposed method more
suitable for newly installed stations. In order to achieve higher performance,
we introduce a regularized Euclidean loss function that favors high congestion
samples over low congestion samples to avoid the impact of the unbalanced
training dataset. A novel dataset for this purpose is designed based on the
traffic data obtained from traffic control stations in northern California.
Extensive experiments conducted on the designed benchmark reflect a successful
congestion prediction
The Symmetric Minimal Surface Equation
For positive functions , where is an open
subset of , the Symmetric Minimal Surface Equation (SME), is
.
Geometrically, the SME expresses the fact that the ``symmetric graph'' ,
defined by , is a minimal (i.e.\ zero mean
curvature) hypersurface in . A function is said to be a singular solution if , and if , uniformly on each compact subset
of , where each is a positive solution of the
SME. The present paper develops are theory of singular solutions of the SME,
including existence, H\"older and Lipschitz estimates for bounded solutions,
and a compactness and regularity theory. We also prove that the singular set
is codimension at most 2
Joint Interference Alignment and Bi-Directional Scheduling for MIMO Two-Way Multi-Link Networks
By means of the emerging technique of dynamic Time Division Duplex (TDD), the
switching point between uplink and downlink transmissions can be optimized
across a multi-cell system in order to reduce the impact of inter-cell
interference. It has been recently recognized that optimizing also the order in
which uplink and downlink transmissions, or more generally the two directions
of a two-way link, are scheduled can lead to significant benefits in terms of
interference reduction. In this work, the optimization of bi-directional
scheduling is investigated in conjunction with the design of linear precoding
and equalization for a general multi-link MIMO two-way system. A simple
algorithm is proposed that performs the joint optimization of the ordering of
the transmissions in the two directions of the two-way links and of the linear
transceivers, with the aim of minimizing the interference leakage power.
Numerical results demonstrate the effectiveness of the proposed strategy.Comment: To be presented at ICC 2015, 6 pages, 7 figure
Determining a piston's top dead center (TDC) in an automobile using installed piezoelectric on a vibrating beam
Smart structures and MEMS are considered important field recently, due to the importance and high capabilities in measurement and the power of reaction and response to changes of the surroundings. This research concerns two fields of practical vision in the automotive industry and discuss the energy recycled industrial vibrations. The goal is to use the PVDF piezoelectric elements in car flywheel for energy harvesting, and compare and replace it with the revolution sensor. This research is totally based on empirical tests data and the result that the use of piezoelectric polymer sensors can harvest energy, was find performing far better than inductive sensors.Keywords: Piezoelectric element; Vibration energy harvesting; smart structures; Revolution sensor; Flywhee
Energy Efficiency Improvement in Surface Mining
This chapter aims to provide an overview of energy efficiency in the mining industry with a particular focus on the role of fuel consumption in hauling operations in mining. Moreover, as the most costly aspect of surface mining with a significant environmental impact, diesel consumption will be investigated in this chapter. This research seeks to develop an advanced data analytics model to estimate the energy efficiency of haul trucks used in surface mines, with the ultimate goal of lowering operating costs. Predicting truck fuel consumption can be accomplished by first identifying the significant factors affecting fuel consumption: total resistance, truck payload, and truck speed. Second, developing a comprehensive analysis framework. This framework involves generating a fitness function from a model of the relationship between fuel consumption and its affecting factors. Third, the model is trained and tested using actual data from large surface mines in Australia, obtained through field research. Finally, an artificial neural network is selected to predict haul truck fuel consumption. The visualized results also clarify the general minimum areas in the plotted fuel consumption graphs. These areas potentially open a new window for researchers to develop optimization models to minimize haul truck fuel consumption in surface mines
Improve Energy Efficiency in Surface Mines Using Artificial Intelligence
This chapter demonstrates the practical application of artificial intelligence (AI) to improve energy efficiency in surface mines. The suggested AI approach has been applied in two different mine sites in Australia and Iran, and the achieved results have been promising. Mobile equipment in mine sites consumes a massive amount of energy, and the main part of this energy is provided by diesel. The critical diesel consumers in surface mines are haul trucks, the huge machines that move mine materials in the mine sites. There are many effective parameters on haul trucksâ fuel consumption. AI models can help mine managers to predict and minimize haul truck energy consumption and consequently reduce the greenhouse gas emission generated by these trucks. This chapter presents a practical and validated AI approach to optimize three key parameters, including truck speed and payload and the total haul road resistance to minimize haul truck fuel consumption in surface mines. The results of the developed AI model for two mine sites have been presented in this chapter. The model increased the energy efficiency of mostly used trucks in surface mining, Caterpillar 793D and Komatsu HD785. The results show the trucksâ fuel consumption reduction between 9 and 12%
The Effect of Morphine on the Incidence of Postoperative Nausea and Vomiting after Strabismus Surgery with Propofol
Background: Corrective strabismus surgery is associated with moderate pain and a very high incidence of postoperative nausea and vomiting (PONV). In our treatment centers Morphine is used a lot and itâs associated with high incidence of PONV and we have few alternative analgesics. The aim of this study was to compare the incidence of postoperative emesis with intravenous morphine in patients undergoing corrective strabismus surgery with propofol anesthesia with the control group.
Methods: In a prospective, double-blind, randomized study, 126 patients who were candidates for strabismus surgery (either sex or any age) were randomly assigned to receive morphine or placebo. None of the patients received any premedication and a standardized anesthesia technique was used for all the patients. The incidence of PONV in patients within 24 hours after the surgery was compared.
Results: During 24 hours after strabismus surgery, 29 (46%) patients in the morphine group and 27 (42.9%) in the control group had nausea. The frequency of vomiting was 11 (17.5%) patients in morphine group and 9 (14.3%) in the control group. There was no significant difference between the two groups regarding nausea episodes (P=0.85) and vomiting episodes (P= 0.8).
Conclusion: According to the results of this study, morphine does not increase PONV after strabismus surgery
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