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To investigate the impact of energy release of reactive material on its damage effect, a modified test chamber was developed to conduct vented chamber tests and penetration tests in both air and argon environments of Al/Ti and Al/TI/W reactive projectiles. The deformation volumes obtained from the scanning results were employed to characterize the damage effect of the reactive materials on multi-spaced plate targets. Several key results include the following: Despite its lower energy density, the Al/Ti/W composite exhibits higher energy release efficiency than the Al/Ti composite. This is attributed to the lower strength of the material, causing it to fragment into finer debris upon impact, thereby facilitating easier ignition and reaction. The Al/Ti/W projectiles induce a significant deformation volume in the plates during penetration tests but exhibit a decrease in penetrative capacity. This phenomenon is attributed to the mechanical characteristics of the Al/Ti/W materials rather than the energy release upon impact. The deflagration of reactive materials during impact does not significantly enhance the structural damage of the target, at least at impact velocities below 1200 m/s.

Accurately and efficiently evaluating the influence of pile–soil interaction on the overall natural frequency of wind turbines is one of the difficulties in current offshore wind power design. To improve the structural safety and reliability of the offshore wind turbine (OWT) systems, a new closed-form solution method of the overall natural frequency of OWTs considering pile–soil interactions with highly effective calculations is established. In this method, Hamilton’s principle and the equivalent coupled spring model (ECS model) were firstly combined. In Hamilton’s theory, the Timoshenko beam assumption and continuum element theory considering the three-dimensional displacement field of soil were used to simulate the large-diameter monopile–soil interaction under lateral load in multilayer soil. Case studies were used to validate the proposed method’s correctness and efficiency. The results show that when compared with the data of 13 offshore wind projects reported in existing research papers, the difference between the overall natural frequency calculated by the proposed method and that reported in this study is within ±10%. This calculation method achieves the goal of convenient, fast and accurate prediction of the overall natural frequency of offshore wind systems.

Abstract Purpose To determine whether the rare NLRP3-Associated Autoinflammatory Disease (NLRP3-AID) is associated with retinal changes and to assess the ocular involvement. Methods A retrospective cohort study of 20 patients(40 eyes) diagnosed with rare NLRP3-AID at Peking Union Medical College Hospital, from April 2015 to August 2022. Patients underwent a comprehensive ophthalmological examination, including visual acuity, intraocular pressure examination, slit-lamp examination, fundus photography, optical coherence tomography(OCT), and fluorescence angiography (FA). Some patients also underwent optical coherence tomography angiography (OCTA). Results This study analyzed 40 eyes of 20 patients (11 [55.0%] male; median age, 25.0 years [range, 12–52 years]) and 13 patients (26 eyes, 65%) demonstrated ocular involvement. The most common ophthalmologic manifestation was conjunctivitis (22 eyes, 84.6%), followed by papilledema (14 eyes, 53.8%), retinopathy (10 eyes, 38.5%), optic atrophy (6 eyes, 23.1%), uveitis (4 eyes, 15.4%), reduced pupil light reflex (3 eyes, 11.5%) and cataracts (2 eyes, 7.7%). Ocular involvement was bilateral in 11 patients (55.0%). Five kinds of retinal lesions were seen in 5 patients (10 eyes, 25%) with NLRP3-AID, including peripheral retinal vascular leakage, microaneurysms, macular ischemia, macular epiretinal membrane formation and drusen. Conclusions Peripheral retinal vascular leakage, macular ischemia, microaneurysms and drusen are newly identified retinal findings in patients with NLRP3-AID, which suggests the importance of detailed retinal examination in these patients.

Heat exchangers with mini-channels, such as the printed circuit heat exchanger (PCHE), are key components for supercritical carbon dioxide (S-CO2) Brayton cycle due to advantages in compactness and structural rigidity. Flow distribution plays an important role for PCHE performance and it is affected by environment conditions like rolling and heaving motions. The flow distributions and heat transfer characteristics among parallel mini-channels for S-CO2 flow under the steady and rolling conditions would be simulated in this paper. Two plateaus/shoulders were observed on the nonuniformity-Reincurve: one was caused by the flow regime changing from laminar to turbulence regime, and another due to the compromise of “heating up” and “flow rate” effects. The rolling effects on the thermal-hydraulic characteristics of S-CO2 flow inside PCHE would be further investigated. In general, the response of thermal-hydraulic characteristics would be slightly delayed, and the rolling effects increase with the rolling frequency, amplitude and radius. As the rolling period increases, the shapes of heat transfer coefficient and friction factor curves would no longer be sinusoidal. The heat transfer characteristics in each channel were also investigated and it could be found that the heat transfer coefficient increases with the flow flux (Re). The effects of rolling conditions could not be neglected for low flow mass rate and high rolling frequency. Adding baffles at manifolds significantly improves the flow distribution under rolling conditions.

The conjugate heat transfer from combustion in furnace to supercritical fluid in tube has been numerically investigated in this study. The mathematic model of the conjugate process has been constructed. The effects of the combustion status in furnace on the conjugate heat transfer process were analysed. The results demonstrate that the heat transfer deterioration of supercritical fluid in the tube will only occur in high heat flux regions such as the high temperature recirculation zone. The swirling air can suppress the high temperature recirculation zone near the furnace wall, which is beneficial to inhibit the heat transfer deterioration of supercritical fluid in the tube.

Periodic replacement models with minimal repairs have been studied extensively. In order to prevent high repair costs after failures, this paper considers the number of failures as another decision variable for replacement policies. We begin with the standard periodic replacement model, and then summarize several extended replacement models with number of failures, using the respective assumptions of whichever occurs first and last, and replacing over planned measure, respectively. Optimum policies of replacement times T, number of periodic times N, and number of failures K are discussed analytically. From the optimization of the integrated models of T, N and K, comparisons among these policies are made in analytical ways to determine which policy should be more economical.

This paper tries to trace our research history briefly from Barlow and Proschan to attain general replacement models. We begin with a random age replacement policy that is planned at a random time Y and call it as random replacement. When the distribution of Y becomes a degenerate distribution placing unit mass at T, age replacement is formulated. We obtain the general formulas for optimum replacement times. We next suppose the unit works for a job with random works, and replacement policies with N cycles are discussed. As follows, we combine age and random replacement models and discuss replacement first, replacement last, replacement overtime, replacement overtime first and replacement overtime last. By formulating the distributions of replacement times with n variables, general replacement models with n replacement times are obtained.

Hydraulic transformer can improve the transmission efficiency of the hydraulic system. As the manual hydraulic transformer cannot achieve automatic control and remote control in the hydraulic system, to meet this challenge, the electro-hydraulic servo plate-inclined plunger hydraulic transformer (EHHT) was proposed in this paper. First, through analyzing the principle of the EHHT, the structure of EHHT is designed based on the theoretical analysis; Secondly, the mathematical model and simulation model of output pressure were created. Finally, the fuzzy control strategy was designed and tested on the experiment bench. Both the simulated and experimental results show that the control strategy can effectively improve the pressure control performance of hydraulic transformer and the theoretical analysis is correct.

Objective To investigate the optic disc changes (ODC) in Chinese patients with NLRP3-associated autoinflammatory disease (NLRP3-AID).Methods Patients who were diagnosed with NLRP3-AID at the Department of Rheumatology, Peking Union Medical College Hospital between April 2015 and December 2022 were retrospectively reviewed and analyzed.Results A total of 20 patients were enrolled in this retrospective study. All 20 patients had a moderate MWS NLRP3-AID phenotype. Thirteen patients (65%) had ocular involvements. The interval between symptoms onset and diagnosis was significantly longer in patients with ocular involvement than in patients without (p = 0.044). The incidence of hearing loss was significantly higher in patients with ocular involvement (p = 0.017), while the incidence of abdominal pain was significantly lower when compared to patients without ocular involvement (p = 0.007). Optic disc swelling (ODS) (50%) was the most common ODC. All of the four T348M mutation carriers within our cohort exhibited ODS with visual-field defects. There was a significant difference between patients with/without ODS regarding the number of patients carrying T348M mutation (p = 0.014). The occurrence of hearing loss and CNS involvement was significantly higher in the group with ODS compared to the group without (p = 0.0014, p = 0.0198). Of the eight patients who underwent lumbar puncture, five presented with intracranial hypertension (IH). ODS was observed in all patients with IH. The serum inflammatory markers were significantly higher in patients with ODS than in those without. Two patients receiving regular subcutaneous IL-1 inhibitor treatment showed improvements in ODC.Conclusions ODC is common among Chinese patients with NLRP3-AID, with ODS being the most common manifestation. Hearing loss and CNS involvement often accompany the occurrence of ODS. The serum inflammatory markers are associated with ODS. The T348M mutation is more likely to lead to ODC with visual-field defects.