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To ensure the privacy of power system users while maximizing the efficiency of decentralized computational resources, this paper presents a novel decentralized power flow algorithm. Its core focus lies in preserving bus privacy through the integration of neighboring partial derivative information. Initially, the algorithm utilizes partial derivative data from adjacent buses to formulate a bus-level voltage iterative function, rooted in the bus power balance equation. Each bus in the power network is treated as an individual computational unit managed by an agent. This process involves scanning the network’s buses, computing estimated bus voltage values using a designated iteration formula, and iterating until convergence is achieved. Subsequent utilization of the latest neighbor information accelerates this iterative process. To fortify the algorithm’s reliability, a strategy assessing local convergence, utilizing the Jacobian matrix at the solution’s convergence, is proposed. The simulation results across various IEEE test systems unequivocally validate the proposed algorithm’s efficacy in power flow computation, showcasing accelerated speed and robust anti-interference capabilities. Compared to the traditional decentralized power flow method at the bus level, this algorithm significantly optimizes the iterative process, slashing the number of iterations by a minimum of 1.36 times. Notably, this efficiency boost amplifies in larger system scales, boasting an impressive reduction of up to 9.21 times fewer iterations.

The sufficiency of electricity market competition and the economy of power system operation require that the economic dispatch should not only preserve the bus privacy but consider network losses. The existing economic dispatch methods, however, can’t preserve the privacy of each bus from leakage and even complicate the solution when they reasonably consider network losses, due to the coupling complexity of network losses. To address these issues, this paper presents a novel distributed economic dispatch (DED) method based on KKT optimality conditions and iteration functions. It focuses on an economic dispatch model that contains bus active power balance equations and generator power limit inequalities. First, the model’s KKT optimality conditions with inequalities are simplified to equivalent pure equality-type optimality conditions. Then a set of iteration functions is created using the Taylor series, which overcomes the difficulty caused by the fact that unknown bus voltage phases are completely contained in the sine and cosine functions of optimality conditions. Finally, a fast fixed-point iteration procedure is proposed for bus agents to solve the economic dispatch model. The proposed method reasonably considers network losses by using the set of bus active power balance equations. It not only preserves the privacy of each bus from leakage but is straightforward in solution (does not complicate the solution). In addition, it is fully bus-level distributed. Numerical simulation results of systems with different sizes verified the effectiveness and advantages of the proposed method.

Hepatitis B virus(HBV) infection remains a global problem, despite the effectiveness of the Hepatitis B vaccine in preventing infection. The resolution of Hepatitis B virus infection has been believed to be attributable to virus-specific immunity. In vivo direct evaluation of anti-HBV immunity in the liver is currently not possible. We have developed a new assay system that detects HBV clearance in the liver after the hydrodynamic transfer of a reporter gene and over-length, linear HBV DNA into hepatocytes, followed by bioluminescence imaging of the reporter gene (Fluc). We employed bioluminescence detection of luciferase expression in HBV-infected hepatocytes to measure the Hepatitis B core antigen (HBcAg)-specific immune responses directed against these infected hepatocytes. Only HBcAg-immunized, but not mock-treated, animals decreased the amounts of luciferase expression, HBsAg and viral DNA from the liver at day 28 after hydrodynamic infection with over-length HBV DNA, indicating that control of luciferase expression correlates with viral clearance from infected hepatocytes.

BACKGROUND: The development of small molecule inhibitors of hepatitis C virus (HCV) core protein as antiviral agents has been intensively pursued as a viable strategy to eradicate HCV infection. However, lack of a robust and convenient small animal model has hampered the assessment of in vivo efficacy of any antiviral compound. METHODOLOGY/PRINCIPAL FINDINGS: The objective of this work was to develop a novel method to screen anti-core protein siRNA in the mouse liver by bioluminescence imaging. The inhibitory effect of two shRNAs targeting the highly conserved core region of the HCV genome, shRNA452 and shRNA523, was examined using this method. In the transient mouse model, the effect of shRNA-523 was detectable at as early as 24 h and became even more pronounced at later time points. The effect of shRNA-452 was not detectable until 48 h post-transduction. In a stable mouse model, shRNA523 reduced luciferase levels by up to 76.4±26.0% and 91.8±8.0% at 6 h and 12 h after injection respectively, and the inhibitory effect persisted for 1 day after a single injection while shRNA-Scramble did not seem to have an effect on the luciferase activity in vivo. CONCLUSIONS/SIGNIFICANCE: Thus, we developed a simple and quantitative assay for real-time monitoring of HCV core protein inhibitors in mice.

A novel hybrid active power filter with multi-injection hybrid active power filter (MIHAPF) branches is proposed in this paper; harmonic current is injected into the grid through multi- branches, and steady dc-side voltage can be gained by controlling the inverter to absorb and release energy from the grid. Furthermore, dividing frequency control method is proposed to improve the performance of MIHAPF. It can compensate the phase and amplitude error of injection current, which is generated by the system delay, injection branches, and output filter. Control precision can also be improved profiting from the control method. Improved ip—iq algorithm is proposed to calculate the amplitude and phase of each integral-order harmonic for the control strategy. Simulation and application results have shown the validity of the proposed MIHAPF, and the proposed dividing frequency control method using improved ip—iq algorithm can improve the filtering performance and ensure the stability of the dc-side voltage. [ABSTRACT FROM AUTHOR]

In a sinusoidal steady-state circuit, how much of an impedance-branch dissipation power should be assigned to each source? The answer is the basis of electricity transmission pricing, such as the pricing of line loss and line security due to thermal limit. However, it is difficult to obtain a unique and common consent answer because of the nonlinearity of power expression. This paper presents two weakly conditioned imputation formulas, respectively for dissipation active- and reactive-power, to answer the question. First, a detailed form of Shapley value formula and three weak conditions are proposed. On this basis, the two imputation formulas are then derived and proved mathematically. The imputation formulas are explicitly in terms of source currents/voltages, thus analytic and easy to compute. They possess eight mathematical and economic features that lay a good foundation for electricity transmission pricing. The two imputation formulas are also extended to actual power systems where trades are conducted in MWh/MVARh instead of amperes/volts. Numerical examples illustrate their computing process and features. [ABSTRACT FROM AUTHOR]