In the platform economy, many brands have already supplied products to platforms (e.g., Amazon.com and JD.com) who operate "self-run (SR)" stores. They face challenges of whether or not operating flagship stores on how determine optimal logistics choice (provided by 3PL providers). To address these challenges, we explore channel selection strategies for through building theoretical models. This paper considers three levels service difference between 3PL. It guides make operational being...

This paper constructs Bai Autonomous Prefecture of Dali's land ecological security assessment index system based on pressure-state-response model, using entropy method and composite to evaluate Dali Prefecture's security’ is 0.60823 in 2009, which good condition. Although the whole prefecture's condition stays comparative security, we should realize economic disparity status varies from city city. The difficulty exploiting, disasters vulnerable ecosystem are also reality face. So how...

The agro-circular economy is the sustainable development strategy, which based on reduce, reuse, recycle principle (referred to as 3-R principle) and including green agriculture, ecological agricultural. There are many issues of agricultural in Erhai Lake Basin, industrial structure single, layout unreasonable, ability resist market risk weak, Non-point source pollution serious so on. In view this, it urgent implement model: energy comprehensive utilization pattern, breeding agriculture...

Developing affordable and scalable energy storage solutions is essential to decarbonizing power systems. The conversion of renewable electricity into chemical carriers such as ammonia has attracted extensive attention from academia industry. Many Power-to-Ammonia (PtA) plants have been conceptualized developed worldwide in recent years. PtA plant an integration multiple electrochemical processes, each with a distinct set operational constraints cost structure. One the problems operation...

New energy is gradually replacing fossil and becoming the main source of electricity. It great significance to analyze small signal stability new stations, while traditional eigenvalue analysis method has limitations such as difficulty in selecting independent state variables. In this paper, discrete space applied photovoltaic-battery storage system (PV-BESs) for analysis. The model based on trapezoidal integration rule first constructed, accompanied by its eigenvalues. Then, eigenvalues are...

Existing research on high-frequency oscillation indicates that the during no-load charging of modular multilevel converter (MMC) station is primarily linked to time delay and ground capacitance AC lines. Nevertheless, a around 2000 Hz has been observed in Rudong high voltage direct current project even when lines are not connected. Except delay, there still exists another key factor oscillation, i.e., transformer stray capacitance. This paper delves into interaction among dynamics MMC...

Recent advancements in Cu-based intermetallics have sparked significant interest electrochemical energy conversion and related fields. This review focuses on the latest developments intermetallics, covering their structures, synthesis...

This paper discusses the optimization of a high-voltage superjunction (SJ) power MOSFET by use fabrication based on porous-silicon formation. In this process, charge-compensating structures are created etching structured macropores directly thin silicon wafer, followed passivating walls and filling pores with oppositely charged polysilicon. The effects charge imbalance thickness passivation layer studied physically numerical-device simulations. It is found that, even small amount imbalance,...

This paper presents a novel approach of coordinating the droop controls between grid-connected variable speed wind turbine (VSWT) and associated energy storage system (ESS) for supporting primary frequency control in power systems. Available reserve from deloaded VSWT, which is function average rotational speed, estimated an efficient manner. Based on available VSWT auxiliary role ESS, coordinated ESS participating redesigned, corresponding algorithm given. Finally, effectiveness proposed...

Data-driven fault diagnosis is increasingly prevalent in recent years for complex systems, but still suffers from two practical difficulties: one the lack of enough historical examples equipment and other absence personalized characteristics to be diagnosed. This paper proposes an adaptive ensemble method resolve these difficulties. The proposed first extracts normal patterns by constructing hidden Markov models (HMMs), respectively, examples. Then decisions made supervised unsupervised...

Graphical Abstract

Based on recording the inputs and outputs of control systems its modules blocks during on-site disturbance experiments tests, an abnormal signal analysis based method for locating oscillation source in is proposed by intensively comparing differences between ideal standard responses actual response a system blocks. The has merit being able to locate power specific By utilizing method, events occurred nuclear plant determined as frequency measurement block PSS digital excitation system.

Modeling of a permanent magnet synchronous generator (PMSG)-based wind energy conversion system is presented for the simulation diverse transients.In order to perform multi-scale transients, back-to-back voltage source converter (VSC) modeled using three different forms including detailed, switched and average models.The PMSG-based WECS implemented in PSCAD/EMTDC.The results show that detailed model VSC give accurate representation, while provides an efficient simulation.

The Message-Passing Interface (MPI) has been increasingly popular among the parallel computing community. However, today's MPI language bindings cannot apply to a heterogeneous environment, such as Internet. In order exploit maximum performance potential on we have implemented in Pure Java, fully platform-independent language. results show that can be successfully Java and of PJMPI (Pure MPI) is actually acceptable. bottlenecks using high their corresponding solutions are also discussed.

PCA had been used on detection of face successfully before. Although also mouth and eye, it has low rate detection. Because more pose than eye can be affected by illumination easily. Interest point a popular way object because its stable property. This paper use Harris corner interest with probability model. The experiment result shows that the correct accuracy position have all enhanced.

Abstract A novel self-injection relativistic backward wave oscillator (RBWO) has been proposed. By introducing a path into the RBWO, small portion of energy in reflector can be coupled to upstream reflector, and then formed electric field region pre-modulate passing electron beam, promote frequency-locking oscillation beam. The pre-modulated beam expected enhance beam-wave interaction suppress parasitic mode oscillation, which is beneficial for maintaining dominant role operating mode....