For islanded microgrids(MGs),distributed control is regarded as a preferred alternative to centralized control for the frequency restoration of ***,distributed control with successive communication restricts the effic...
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For islanded microgrids(MGs),distributed control is regarded as a preferred alternative to centralized control for the frequency restoration of ***,distributed control with successive communication restricts the efficiency and resilience of the control *** address this issue,this paper proposes a distributed event-triggered control strategy for the frequency secondary control in islanded *** proposed event-triggered control is Zeno behavior free and enables each DG to update and propagate its state to neighboring DGs only when a specific“event”occurs,which significantly reduces the communication *** with the existing event-triggered control,a trigger condition checking period of the proposed event-triggered control is provided to reduce the computation burden when checking the trigger ***,using the aperiodicity and intermittent properties of the communication,a simple detection principle is proposed to detect and isolate the compromised communication links in a timely and economic fashion,which improves the resilience of the system against FDI ***,the control effectiveness of the proposed control scheme is validated by the simulation results of the tests on an MG with 4 DGs.
With the advent of the 5G era, high-precision localization based on mobile communication networks has become a research hotspot, playing an important role in indoor emergency rescue in shopping malls, smart factory ma...
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With the advent of the 5G era, high-precision localization based on mobile communication networks has become a research hotspot, playing an important role in indoor emergency rescue in shopping malls, smart factory management and tracking, as well as precision marketing. However, in complex environments, non-line-of-sight (NLOS) propagation reduces the measurement accuracy of 5G signals, causing large deviations in position solving. In order to obtain high-precision position information, it is necessary to recognize the propagation state of the signal before distance measurement or angle measurement. In this paper, we propose a dynamic multi-level optimization of comprehensive features (DMOCF) network model for line-of-sight (LOS)/NLOS identification. The DMOCF model improves the expression ability of the deep model by adding a res2 module to the time delay neural network (TDNN), so that fine-grained feature information such as weak reflections or noise in the signal can be deeply understood by the model, enabling the network to realize layer-level feature processing by adding Squeeze and Excitation (SE) blocks with adaptive weight adjustment for each layer. A mamba module with position coding is added to each layer to capture the local patterns of wireless signals under complex propagation phenomena by extracting local features, enabling the model to understand the evolution of signals over time in a deeper way. In addition, this paper proposes an improved sand cat search algorithm for network parameter search, which improves search efficiency and search accuracy. Overall, this new network architecture combines the capabilities of local feature extraction, global feature preservation, and time series modeling, resulting in superior performance in the 5G channel impulse response (CIR) signal classification task, improving the accuracy of the model and accurately identifying the key characteristics of multipath signal propagation. Experimental results show that the N
The distributed randomness beacon(DRB) is a crucial tool for continuously generating unpredictable, bias-resistant,and publicly verifiable random numbers on a regular basis. This is particularly useful for application...
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The distributed randomness beacon(DRB) is a crucial tool for continuously generating unpredictable, bias-resistant,and publicly verifiable random numbers on a regular basis. This is particularly useful for applications such as lotteries, electronic voting, and cryptographic parameter generation. However, existing studies either require complex communication or rely on a public bulletin board to meet security requirements. This brings a performance bottleneck when dealing with a large number of participants. This paper introduces a novel DRB protocol PltcRB based on timed commitments, eliminating the need for a public bulletin board. Our approach achieves optimal communication complexity of O(n) while maintaining the desired properties of a DRB protocol. The computation complexity is also O(n) when n is larger than the security parameter κ. These results demonstrate the practicality and performance of PltcRB, supported by our experimental analysis under various configurations.
In this paper,we construct a bounce inflation cosmological scenario in the framework of the modified symmetric teleparallel gravity,namely f(Q)theory,and investigate the tensor perturbations *** is well-known,the tens...
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In this paper,we construct a bounce inflation cosmological scenario in the framework of the modified symmetric teleparallel gravity,namely f(Q)theory,and investigate the tensor perturbations *** is well-known,the tensor perturbations generated in the very early Universe(inflation and pre-inflation regions)can account for the primordial gravitational waves(PGWs)that are to be detected by the next generation of GW *** discuss the stability condition of the tensor perturbations in the bounce inflation process and investigate in detail the evolution of the perturbation *** general form of the tensor power spectrum is obtained both for large as well as small scale *** a result,we show both kinds of modes(short or long wavelength modes),and the tensor spectrum may get a positive tilt in the parametric range where the tensor perturbation proves to be stable—this interestingly hints an enhancement of gravitational waves’amplitude in the background of the f(Q)bounce-inflation ***,we study the LQC-like scenario as a specific case of our model,in which,the primordial tensor power spectrum turns out to be nearly scale-invariant on both small and large scales.
In this paper,the coupled sloshing and motion characteristics of a cylindrical floating production storage offloading(CFPSO)are numerically investigated by means of computational fluid dynamics(CFD)*** simulations are...
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In this paper,the coupled sloshing and motion characteristics of a cylindrical floating production storage offloading(CFPSO)are numerically investigated by means of computational fluid dynamics(CFD)*** simulations are performed using an in-house CFD solver naoe-FOAM-SJTU which is developed based on *** active wave generating-absorbing boundary condition(GABC)is utilized for wave generation and *** stabilized k-omega SST turbulence model are used to avoid excessive eddy viscosity near the free *** with and without partially filled liquid tanks in regular waves with different wave periods are simulated and vertical planar motions such as surge,heave and pitch response amplitude operators(RAOs)are *** due to liquid sloshing and wave loads are extracted and *** free surface motions inside liquid tanks in one wave period presented to explain the motion characteristics.
Efficient control of the desulphurization system is challenging in maximizing the economic objective while reducing the SO_(2) emission concentration. The conventional optimization method is generally based on a hiera...
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Efficient control of the desulphurization system is challenging in maximizing the economic objective while reducing the SO_(2) emission concentration. The conventional optimization method is generally based on a hierarchical structure in which the upper optimization layer calculates the steady-state results and the lower control layer is responsible to drive the process to the target point. However, the conventional hierarchical structure does not take the economic performance of the dynamic tracking process into account. To this end, multi-objective economic model predictive control(MOEMPC) is introduced in this paper, which unifies the optimization and control layers in a single stage. The objective functions are formulated in terms of a dynamic horizon and to balance the stability and economic performance. In the MOEMPC scheme, economic performance and SO_(2) emission performance are guaranteed by tracking a set of utopia points during dynamic transitions. The terminal penalty function and stabilizing constraint conditions are designed to ensure the stability of the system. Finally, an optimized control method for the stable operation of the complex desulfurization system has been established. Simulation results demonstrate that MOEMPC is superior over another control strategy in terms of economic performance and emission reduction, especially when the desulphurization system suffers from frequent flue gas disturbances.
Charismatic species are often reported by the media,providing information for detecting population status and public *** identify the number and distribution of free-living Black Swan(Cygnus atratus),a charismatic ali...
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Charismatic species are often reported by the media,providing information for detecting population status and public *** identify the number and distribution of free-living Black Swan(Cygnus atratus),a charismatic alien species in Chinese mainland and to detect the public and the media attitudes to the species,we analyzed the reports and emotional tendency from media coverage in 2000-2022 using manual reading,crawler extraction and latent Dirichlet allocation.A total of 6654 Black Swans were reported at 711 sites,including 147 individuals at 30 nature *** breeding was reported at one-fourth of the total sites,including five nature *** proportion of positive emotional tendency to Black Swans was overwhelming in the reports and was higher than that to alien species in general,suggesting that the public and the media are unaware of the risk of biological *** management of invasive species requires the media clarifies the invasion risk of charismatic alien *** the unity between the harmfulness of abstract concept of alien species and the charisma of a specific alien species among the public help effective management.
It is of utmost importance to mitigate environmental pollution by employing clean and environmentally friendly technology for the treatment of textile sludge. This paper focuses on utilizing textile sludge as the prim...
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It is of utmost importance to mitigate environmental pollution by employing clean and environmentally friendly technology for the treatment of textile sludge. This paper focuses on utilizing textile sludge as the primary raw material in the production of lightweight aggregates for the construction industry, using a non-sintered method that is more eco-friendly compared to traditional sintering technology. The optimal raw material ratio and process parameters for fabricating non-sintered lightweight aggregates are determined as follows: a sludge/cement ratio of 2.25, fly ash addition of 5%, additive addition of 1%, and curing time of 28 days. These parameters result in physical properties including a compressive strength of 6.93 MPa, bulk density of 753 kg/m3, and 1h water absorption rate of 17.98%. The hydration mechanisms have been investigated through X-ray diffraction and scanning electron microscopy, revealing that C-S-H gel and Ettringite produced by the hydration reaction significantly contribute to the physical properties. Furthermore, it has been observed that Zn2+ present in the textile sludge reacts within the hydration system, ultimately transforming into insoluble Ca(Zn(OH)3)22H2O and Zn(OH)3-. These compounds are captured by C-S-H gel, effectively eliminating potential risks associated with heavy metal Zn during the resource utilization process of textile sludge. In summary, the innovative method proposed in this paper could effectively achieve the resourceful and harmless utilization of textile sludge.
Half-integer microwave induced steps(Shapiro steps)have been observed in many different Josephson junction systems,which have attracted a lot of attention because they signify the deviation of current phase relation(C...
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Half-integer microwave induced steps(Shapiro steps)have been observed in many different Josephson junction systems,which have attracted a lot of attention because they signify the deviation of current phase relation(CPR)and uncover many unconventional physical *** this article,we first report the discovery of half-integer Shapiro steps in MgB_(2)focused He ion beam(He-FIB)Josephson *** half-integer steps'dependence on microwave frequency,temperature,microwave power,and magnetic field is also *** find that the existence of half-integer steps can be controlled by the magnetic field periodically,which is similar to that of high temperature superconductor(HTS)grain boundary junctions,and the similarity of the microstructures between gain boundary junctions and He-FIB junctions is *** a consequence,we mainly attribute the physical origin of half-integer steps in MgB_(2)He-FIB junctions to the model that a He-FIB junction is analogous to a parallel junctions'*** results show that He-FIB technology is a promising platform for researching CPR in junctions made of different superconductors.
Ultrasound-guided intrauterine insemination (IUI) has been successfully employed in cynomolgus macaques, yet its effectiveness in large-scale, multi-age cohorts has not been fully explored. Here, we implemented IUI wi...
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Ultrasound-guided intrauterine insemination (IUI) has been successfully employed in cynomolgus macaques, yet its effectiveness in large-scale, multi-age cohorts has not been fully explored. Here, we implemented IUI within large breeding colonies to boost pregnancy rates in cynomolgus macaques. Ovulation timing was estimated by monitoring menstrual bleeding, after which IUI was performed. We then compared single menstrual cycle (SMC) pregnancy rates between IUI groups and harem-style mating groups. Our findings revealed that the overall pregnancy rate in the IUI group was significantly higher than in the harem-style breeding group across all ages. Notably, this advantage was mainly attributable to monkeys over 10 years old;in contrast, no significant difference was observed among 4-5-year-old and 6-10-year-old monkeys. Although pregnant females in the IUI group exhibited a higher birth rate compared to those in harem-style breeding, this difference was not statistically significant. Collectively, these results establish a basis for refining reproductive technologies in older cynomolgus macaque breeding programs and highlight potential improvements in managing large-scale colonies.
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