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Household power conversion stages process significant amounts of power when they add up to form a microgrid. Microinverters are considered one of the best choices to utilize the renewable energy harvested power. Microinverter integration encounters several challenges when interfaced with expanding microgrids. This paper proposes a coupled inductor-based boost microinverter operating in dual mode time sharing technique for renewable energy applications. It is composed of an absolute sinewave modulated voltage boost converter and series capacitor connected to the secondary winding of the coupled inductor followed by a single-phase Full bridge inverter. The coupled inductor integration allows a significant reduction in current ripple and improved energy conversion efficiency. In the proposed microinverter, the DC link voltage is not required to be constant, instead, it process an absolute sinewave modulated voltage and then it is unfolded to AC and fed into the grid. The DC link capacitor is substituted by an efficient AC thin film type capacitor. The dual mode time-sharing principle intends to reduce the switching losses of the microinverter and consequently achieves high conversion efficiency. The proposed converter’s analysis, design, and simulation are validated on a 2.0 kW setup system using PSIM simulation software. The feasibility and performance of this new microinverter topology is proved experimentally via laboratory prototype. The current ripple can be reduced to one half in case of matching coupled inductor primary and secondary windings compared to the typical boost converter. In another scenario, the current ripple can be fully eliminated in either of the coupled inductor windings when winding inductance equals to the mutual inductance. The proposed microinverter topology offers a notable enhancement in power conversion performance that reached 97%. In addition, a high-quality sinusoidal output current waveform of 1.1% total harmonic distortion is achieved.

Background. The introduction of new means of technological equipment for the processes of experimental research of on-board radio-electronic equipment of satellite control systems at the stages of its production and operation support necessitates updating the corresponding methodological support, taking into account the formed directions of digitalization in the rocket and space industry. Materials and methods. A new technical solution for the hardware-software emulator of interface modules is implemented on the use of hardware-software resources in the time-sharing mode. The introduction of the emulator into production activities increases the degree of automation of the production processes of the enterprise, and new methods of its application implement the mechanisms for information support of the life cycle processes of the onboard radio-electronic equipment of satellite. Results. A hardwaresoftware complex has been developed, its provide emulation of the operation of eight interface modules for the computing module of the onboard equipment in hard real-time mode based on one set of technological equipment. The functionality of the emulator provided an increase in the information content of the ongoing research of the equipment due to the possibility of implementing extended test methods (imitation of failures of equipment units, debugging the mode of autonomous preservation of the attitude of the satellite, working with backup sets, etc.). Methods for using the emulator as a means of technological equipment for applied experimental research on the onboard radio-electronic equipment of satellite at the stages of its design and operation are proposed. Conclusions. The implementation of a hardware-software emulator of interface modules into the organizational and technical system of the enterprise in combination with new methodological support for the processes of applied experimental research made it possible to: implement the mechanisms for integrating and managing service data about the product within the framework of a single information space of the enterprise; to improve the quality of ground experimental testing of equipment at the stages of design and operation; reduce material costs for the necessary technological equipment for testing; reduce the influence of the human factor on the reproducibility of test results; as well as to improve the fault tolerance of spacecraft as a whole at the stage of their operation.

Motivated by time-sharing systems with deadlines, we introduce the study of the following problem. We are given m machines and n jobs, as well as a set of tolerance capacities u i j ≥ 0 for every job j and machine i. Can we assign the jobs so that, if job j ends up on machine i , the total size of jobs that are processed on i is at most u i j ? We define two natural optimization versions: (i) Maximize the total weight of jobs that can be assigned without violating the tolerance capacities. (ii) Minimize the amount ρ ≥ 1 by which capacities have to be scaled so that all jobs can be assigned. For (i), we provide constant-factor approximations even in the presence of additional side-constraints. For (ii), we provide a strong inapproximability result and integrality gap lower bounds for two key relaxations. [ABSTRACT FROM AUTHOR]

Software-defined networking (SDN) makes network management easier by using a controller to govern all switches, but the controller may become a performance bottleneck. Distributed SDN control is a promising solution, which lets multiple controllers divide the work, where each controller manages a part of the network. Switch migration is one common means to the load balance of controllers, which transfers some switches to different subnets based on the workloads of their controllers. The paper proposes a time-sharing switch migration (TSSM) scheme to provide more refined load sharing for controllers, which allows two controllers to share a switch’s load sequentially in the same period. When a controller is overloaded, TSSM finds assistant controllers to share its workload by selecting proper switches for migration and also deciding the time to perform migration. In this way, the workload of each controller can be kept below a given threshold. We implement the TSSM scheme on the open network operating system (ONOS) to attest to its feasibility. Experimental results show that TSSM can reduce 98% of the occurrences of overload for controllers as compared with the original OpenFlow method. Moreover, TSSM can save about 78% of the migration cost than the churn-triggered migration method. [ABSTRACT FROM AUTHOR]

For the various imbalances of series-connected cells, the existing balancing methods has the disadvantages of limited energy flow direction and unnecessary charge transfer. Based on flyback converter, this paper proposes a multi-winding input and multi-winding output bi-directional equalization topology. It can realize any cell (s) to any cell (s) balancing, which has the advantage of flexible balancing energy flow path. This paper adopts the control strategy of time-sharing participation in equalization according to the order of the initial state of charge (SOC) of cells, it can solve the problem of unnecessary energy transfer and simplify the control logic. In addition, it gets rid of the influence of energy loss of the circuit components on the setting of the fixed equalization end judgment value, whether equalization ends or not depends on the difference between the discharge cells and the charge cells in this paper, which has the advantage of random adaptive adjustment. In this paper, the operational principle of the proposed circuit are analyzed and the equalization strategy is described in detail. A comparison in balancing performance between the conventional equalization topology based on flyback converter and proposed topology is shown in static state. To verify the validity of the proposed method, the simulation experiment of four cells series-connected is carried out, and the simulation results show that the balancing method proposed in this paper has faster equalization speed and higher equalization energy transfer efficiency.

In this letter, a channel switching problem is investigated in the presence of jamming based on a game theoretic approach. First, a convex formulation of the optimal channel switching problem is proposed for a given jamming strategy. Then, considering a fixed channel switching strategy, an explicit solution of the optimal jammer power allocation problem is obtained. Consequently, a game theoretic formulation is proposed and the existence of a pure-strategy Nash equilibrium is shown for the proposed channel switching game between the transmitter and the jammer. [ABSTRACT FROM AUTHOR]

In the two-user Gaussian interference channel (IFC) with Gaussian inputs and treating interference as noise (TIN), it depends on the assumptions about time-sharing whether improper signals (asymmetric complex signals) can bring benefits over proper signals. If no time-sharing is allowed (pure strategies) or the convex hull formulation is used (only data rates can be averaged), improper signaling can lead to a larger rate region than optimal proper signaling. However, when coded time-sharing is allowed, i.e., both the data rates and the transmit powers can be averaged, the whole rate region can be achieved by proper signaling. Here, we show that the same is true in the multiple-input/single-output (MISO) Z-interference channel (ZIFC). We provide an analytical proof for the optimality of proper signaling in the case of coded time-sharing, and we numerically demonstrate gains by improper signaling in the cases without coded time-sharing. [ABSTRACT FROM AUTHOR]

In this work, a novel time and relay shared (TRS) based full/half duplex (FD/HD) cooperative non-orthogonal multiple access (C-NOMA) scheme namely TRS FD/HD C-NOMA is proposed to efficiently exploit the spectrum of unpaired users in the wireless communication system. More specifically, a scenario has been investigated where cell edge users (CEUs) are more than the cell centre users (CCUs) and the base station has no direct connection with the CEUs. A CCU is employed as a shared relay to form clusters with the CEUs in a time-sharing fashion. To characterize the performance of the proposed scheme, four performance metrics ergodic capacity, outage probabilities, system throughput and system efficiency are discussed. More particularly, ergodic sum capacities are analytically derived and an exact closed-form expression of the outage probabilities is derived for three users in the system. Numerical results show that the TRS FD/HD C-NOMA scheme outperforms the conventional benchmarks. The ergodic capacities and outage performance of TRS FD C-NOMA enhanced in low SNR regime whereas due to the inclusion of loop interference in FD, TRS HD C-NOMA performs better in high SNR regime. Additionally, the system throughput and efficiency are also improved. [ABSTRACT FROM AUTHOR]

It is a research that questioned and investigated how is the protection of possession in the case of disseisin practiced against co-owners in the time-sharing regime of arts. 1.358-8 to 1.358-N of the Civil Code. For this, the research worked with two hypothetical situations: the first is the case of a disseisin practiced by a third party, that is, by a person outside the time-sharing contract; and the second concerns the possibility of the disseisin being practiced by one of the co-owners against another specifically or against all the others. To confirm the hypothesis, the research had to discuss, preliminarily, about the possibility or not of the split of possession (direct and indirect) in time-sharing, demonstrating that there is such a possibility, both in theoretical and practical bias. In order to achieve these objectives, the research carried out a qualitative bibliographic review to deductively confirm the hypothesis of the split of possession and disseisin practiced among co-owners. [ABSTRACT FROM AUTHOR]

So-called improper complex signals have been shown to be beneficial in the single-antenna two-user Gaussian interference channel under the assumptions that all input signals are Gaussian and that we treat interference as noise (TIN). This result has been obtained under a restriction to pure strategies without time-sharing, and it was extended to the case where the rates, but not the transmit powers, may be averaged over several transmit strategies. In this paper, we drop such restrictions and discuss the most general case of coded time-sharing, where both the rates and the powers may be averaged. Since coded time-sharing can in general not be expressed by means of a convex hull of the rate region, we have to account for the possibility of time-sharing already during the optimization of the transmit strategy. By means of a novel channel enhancement argument, we prove a surprising result: proper signals are optimal if coded time-sharing is allowed. In addition to establishing this result, we present an algorithm to compute the corresponding achievable rate region. [ABSTRACT FROM AUTHOR]

We consider joint optimization of user-to-base-station (BS) association, and time-frequency resource block (RB) and power allocation in heterogeneous networks (HetNets). The objective is to develop a design: 1) that maximizes the number of users accommodated in the network while satisfying their quality of service demands and 2) that minimizes usage of the resources required to meet these demands. We investigate two novel instances of HetNets with opportunistic RB-reuse. In the first instance, user-to-BS associations and power allocations can be time-shared, and the RBs can be reused during the signaling interval. For this instance, it is shown that the design problem can be approximated by a problem that yields tight convex upper and lower bounds on the objective. In contrast, the second instance represents a case in which the RBs can be reused, but the user-to-BS associations and power allocations are not time-shared, and hence, fixed throughout the signaling interval. The latter case gives rise to a combinatorial optimization problem, which we provide an approximate solution for by using a polynomial-complexity two-phase approach based on semidefinite relaxation with randomization. [ABSTRACT FROM PUBLISHER]

It has recently been shown that improper signaling enlarges the rate region of the Gaussian single-antenna one-sided interference channel (Z-interference channel, ZIFC) under the assumptions that all input signals are Gaussian and that interference is treated as noise. It was pointed out that this result also holds if time-sharing between different operation points is allowed. However, the existing literature has considered the problem only for time-sharing under short-term average power constraints, i.e., if the average transmit powers are limited individually in each time slot. We consider the same problem under long-term average power constraints, where the transmit powers are limited only after averaging over all time slots. Interestingly, this modification changes the outcome of the study significantly: we can show that improper signaling can no longer bring any gains in this case. [ABSTRACT FROM PUBLISHER]

Bacteria are far more intelligent than we can think of. They adopt different survival strategies to make their life comfortable. Researches on bacterial communication to date suggest that bacteria can communicate with each other using chemical signaling molecules as well as using ion channel mediated electrical signaling. Though in past few decades the scopes of chemical signaling have been investigated extensively, those of electrical signaling have received less attention. In this article, we present a novel perspective on time-sharing behavior, which maintains the biofilm growth under reduced nutrient supply between two distant biofilms through electrical signaling based on the experimental evidence reported by Liu et al., in 2017. In addition, following the recent work by Humphries et al. Cell 168(1):200-209, in 2017, we highlight the consequences of long range electrical signaling within biofilm communities through spatially propagating waves of potassium. Furthermore, we address the possibility of two-way cellular communication between artificial and natural cells through chemical signaling being inspired by recent experimental observation (Lentini et al. 2017) where the efficiency of artificial cells in imitating the natural cells is estimated through cellular Turing test. These three spectacular observations lead us to envisage and devise new classical and quantum views of these complex biochemical networks that have never been realized previously. [ABSTRACT FROM AUTHOR]