Yan Jin

To realize the target business process in the assumed business environment, it is essential to have the ability to understand the process design elements and their settings that are effective in achieving the goal, and the ability to select the most appropriate one among multiple alternatives derived from the combinations of those design elements and settings. In service businesses such as IT support services and factory maintenance services, which provide intangible products such as actions, it is necessary to take into account the effects of two types of uncertainty: uncertainty caused by the external environment, which is the probabilistic generation of demands due to demand that is difficult to predict, and uncertainty caused by the internal environment, which is the generation of processing costs other than planned processing such as exceptions and communications for coordination that occur probabilistically in the processing process. Therefore, this study proposes a business process design methodology based on discrete event simulation through a case study of a business process in the IT department of one company that processes for both predictable and unpredictable demand. In the proposed design method, service business process design is classified into two categories, static structure design and operational guideline design, and Design Variables are selected from each category. By changing the settings of the selected Design Variables, various combinations of alternative processes were created, and process designs that satisfy the goals were identified through simulation predictions. The case study results showed that the proposed method can efficiently explore optimal business process designs by identifying Design Variables and their settings that are effective in achieving goals. The case study quantitatively showed the effect of a change in the method of selecting the next request to be processed on improving the reliability of the process.

The cooling intensity of high-temperature slab critically depends on the ability of droplets to penetrate the vapor film, which is governed by the velocity and size of droplets. These characteristics, in turn, are significantly influenced by the nozzle design and process parameters. However, the specific relationship between distribution uniformity of droplet velocity and droplet size and process parameters remains insufficiently characterized. In this study, a typical internal mixing air-mist nozzle of secondary cooling zone was taken as the research object, the velocity and size of droplets across the spray zone were systematically measured, and the effects of spray distance, air pressure and water pressure on these droplet characteristics distributions were thoroughly analyzed. Key findings reveal that the droplet velocity decreases radially from the spray center toward the edges. Simultaneously, the distribution range of droplet diameter and the Sauter mean diameter ( d 32 ) exhibit a non-monotonic trend, initially decreasing before increasing. Increasing the spray distance expands the droplet dispersion but reduces both the droplet velocity and d 32 in the center zone. The higher air pressure and lower water pressure facilitate higher droplet velocities in the center zone, leading to a decrease in overall droplet diameter and d 32 . It is evident that air pressure emerges as the primary factor influencing the nozzle atomization performance. Notably, while increasing air pressure or decreasing water pressure diminishes the horizontal uniformity of the droplet vertical velocity component, it markedly improves the uniformity of d 32 distribution. Optimal horizontal uniformity of the mean impact Weber number of droplets was observed at an air pressure of 0.3 MPa and a water pressure of 0.4 MPa, as well as at an air pressure of 0.4 MPa and a water pressure of 0.5 MPa.

The microstructure and anisotropy of the solid–liquid interface hold significant importance in a wide range of fields, such as rock mechanics, mineral processing, and powder technology. Despite the prevalence of anisotropic properties in calcite, the underlying physical mechanisms remain poorly understood. Focusing on surface energy, we established a quantitative relationship for surface broken bonds density ( D b ) and interlayer spacing ( d ) on surface energy: γ dry = 0.021 D b – 1.036 d + 0.77, which provided a novel approach to evaluating surface stability and reactivity of calcite. Examination of anisotropic surface properties revealed the (104) calcite surface as the most common cleavage surface owing to its lower surface energies, smaller D b, and larger d . Furthermore, the effects of water coverage and salinity on surface energy were explored, indicating a negative relationship between water coverage and surface energy of (104) calcite. The interaction of water with calcite was observed to affect surface energy, with water adsorption sites being occupied by salt ions. By incorporating contact angle measurements and charge transfer analyses, we elucidated the interaction mechanisms governing surface wettability and offered new insights into the adsorption behavior of water on calcite surfaces, which contributed to advancing the field of mineral surface science and the interaction processes at solid–liquid interfaces.

Multimodal Large Language Models (MLLMs) are widely used in various fields due to their powerful cross-modal comprehension and generation capabilities. However, more modalities bring more vulnerabilities to being utilized for jailbreak attacks, which induces MLLMs to output harmful content. Due to the strong reasoning ability of MLLMs, previous jailbreak attacks try to explore reasoning safety risk in text modal, while similar threats have been largely overlooked in the visual modal. To fully evaluate potential safety risks in the visual reasoning task, we propose Visual Reasoning Sequential Attack (VRSA), which induces MLLMs to gradually externalize and aggregate complete harmful intent by decomposing the original harmful text into several sequentially related sub-images. In particular, to enhance the rationality of the scene in the image sequence, we propose Adaptive Scene Refinement to optimize the scene most relevant to the original harmful query. To ensure the semantic continuity of the generated image, we propose Semantic Coherent Completion to iteratively rewrite each sub-text combined with contextual information in this scene. In addition, we propose Text-Image Consistency Alignment to keep the semantical consistency. A series of experiments demonstrates that the VRSA can achieve a higher attack success rate compared with the state-of-the-art jailbreak attack methods on both the open-source and closed-source MLLMs such as GPT-4o and Claude-4.5-Sonnet.

Tendon injury, resulting from repetitive strain or acute trauma, often leads to pain, reduced mobility, and impaired healing due to the limited regenerative capacity of tendon tissue. Adipose-derived stem cells (ADSCs) exosomes show therapeutic promise, though their mechanisms are unclear. We demonstrated that ADSC-Exos delivers miR-212-5p to tendon-derived stem cells (TDSCs), thereby enhancing their proliferation, migration, and tenogenic differentiation. miR-212-5p directly suppresses forkhead box protein O1 (FOXO1) by binding to its 3'UTR. This downregulation relieves transcriptional repression of protein phosphatase 1A (PP1A), thereby increasing its expression and leading to dephosphorylation and activation of Yes-associated protein 1 (YAP1) signaling. In vivo, ADSC-derived exosomal miR-212-5p promotes tendon repair in male C57BL/6 mice by downregulating FOXO1 and activating YAP1 signaling. Taken together, these findings demonstrate that ADSC-derived exosomal miR-212-5p promotes tendon repair by downregulating FOXO1 to modulate the PP1A/YAP1 axis, highlighting a exosome-based regulatory mechanism and suggesting potential therapeutic targets for tendon injury management.

Abstract Low-viscosity slickwater fracturing fluids have been extensively employed in the exploration and development of shallow shale gas reservoirs in the Gulong region. Conventional slickwater systems fail to meet field operational requirements as exploration advances into deep, high-pressure shale formations. Consequently, there is an urgent need to develop a novel fracturing fluid capable of real-time switching between low-viscosity and high-viscosity fluids to reduce operational costs. In this study, a novel friction reducer (PLD) was synthesized using acrylamide (AM), acrylic acid (AA), 2-acrylamido-2-methylpropanesulfonic acid (AMPS), and a dual-hydrophobic long-chain monomer (LD). A series of laboratory tests were conducted to evaluate the system's rheological properties, friction reduction performance, salt tolerance, and proppant-carrying capacity. Rheological tests demonstrated a significant increase in viscosity as the PLD concentration raised from 0.1 wt% to 2.0 wt%. The low-concentration PLD solution exhibited outstanding friction reduction, achieving a rate exceeding 75% across a wide flow velocity range. High-concentration PLD demonstrated good salt tolerance, shear resistance, and proppant-carrying capacity. At a salinity of 20,000 mg/L, PLD maintained good stability. Temperature and shear resistance tests showed that the 1.2 wt% PLD solution at 120 °C and the 2.0 wt% PLD solution at 145 °C both maintained a final apparent viscosity above 50 mPa·s. Proppant-carrying tests confirmed its effective proppant suspension capability. In summary, the PLD friction reducer exhibits high-efficiency friction reduction at low concentrations and significant proppant-carrying capacity at high concentrations, making it suitable for hydraulic fracturing operations in complex-geology shale gas reservoirs.

Sonodynamic therapy (SDT) is a novel anti-tumor approach that offers the advantages of deep penetration, high therapeutic efficacy, and minimal damage to normal tissues. However, the organic sonosensitizers tetraphenylporphyrin can inhibit the production of reactive oxygen species (ROS) due to the intermolecular π-π stacking effect, resulting in a poor SDT effect. SDT utilizing oxygen-dependent sonosensitizers are frequently limited by the hypoxic microenvironment characteristic of solid tumors. Herein, we have successfully developed an enhanced SDT self oxygen supplying delivery system based on cyclodextrin polyrotaxane to inhibit the π-π stacking effect between tetraphenylporphyrin molecules and improve the hypoxic microenvironment. A "one-stone-two-birds" strategy was proposed. On one hand, the spatial effect of cyclodextrin and polyrotaxane was utilized to enhance the yield of ROS from the sonosensitizers agent porphyrin. On the other hand, the GOx and manganese dioxide nanozyme were loaded onto polyrotaxane through electrostatic adsorption, enabling the reversal of hypoxic environment at the tumor site through a cascade reaction. Ultimately, the prepared polyrotaxane nanoparticles, combined with targeted accumulation to enhance SDT efficacy and starvation therapy, resulted in a 76 % suppression of tumor growth. This study develops an innovative approach to enhance SDT performance of tetraphenylporphyrin via cyclodextrin polyrotaxane spatial effects, while offering a novel strategy to alleviate tumor hypoxia.

Abstract Reinforcement learning (RL) has demonstrated remarkable potential in robotic manipulation but faces challenges in sample inefficiency and lack of interpretability, limiting its applicability in real-world scenarios. Enabling the agent to gain a deeper understanding and adapt more efficiently to diverse working scenarios is crucial, and strategic knowledge utilization is a key factor in this process. This paper proposes a Knowledge Capture, Adaptation, and Composition (KCAC) framework to integrate knowledge transfer into RL through cross-task curriculum learning systematically. KCAC is evaluated using a two-block stacking task in the CausalWorld benchmark, a complex robotic manipulation environment. To our knowledge, existing RL approaches fail to solve this task effectively, reflecting deficiencies in knowledge capture. In this work, we redesign the benchmark reward function by removing rigid constraints and strict ordering, allowing the agent to maximize total rewards concurrently and enabling flexible task completion. Further, we define two self-designed sub-tasks and implement a structured cross-task curriculum to facilitate efficient learning. As a result, our KCAC approach achieves a 40% reduction in training time while improving task success rates by 10% compared to traditional RL methods. Through extensive evaluation, we identify key curriculum design parameters—sub-task selection, transition timing, and learning rate—that optimize learning efficiency and provide conceptual guidance for curriculum-based RL frameworks, offering valuable insights into curriculum design in RL and robotic learning.

Abstract We present a novel, modular Graph based Vision-Language-Action (VLAG) framework designed for long-horizon robotic manipulation tasks. Our approach integrates a graph-based planner with dedicated vision, language, and action modules, enabling robust and efficient task planning and execution. The graph planner serves as a high-level decision-making entity that interprets visual observations and language instructions to select appropriate task sequences. Specifically, our framework leverages a vision model with a multi-layer perceptron to extract key environmental features from both RGB and depth images. The language model is fine-tuned from a pre-trained model to enhance instruction-to-task pairing accuracy, thus having reliable and robust task recognition. The action model is built on the Action Chunking with Transformers (ACT) architecture, modified to accommodate the vision and language modalities. The graph planner is crucial to the framework’s functionality as it allows the combination of the strengths of the vision, language, and action modules, leading to a system that is both adaptable and computationally efficient. Overall, VLAG’s modular design enables the flexible integration of its components, providing a scalable solution for robotic manipulation tasks in both seen and unseen environments.

Large-extent movements (LEMs) are vital for daily activities, and their recovery remains a challenge in neurorehabilitation due to inevitable loading on muscles. Since inhibitory cTBS may facilitate recovery but also disrupt task control, we ask whether a previously identified linear relationship between load and cortical activation would retain, after cTBS over the contralateral supplementary motor area (SMA). It will set a benchmark for choosing resistance during brain stimulation. Hemodynamic activities of SMA and M1 during LEMs were monitored by functional Near-Infrared Spectroscopy (fNIRS) in this study. Twelve healthy participants received 40s of cTBS over SMA, before and after which the participants were instructed to complete LEMs with varying loads (0, 3, and 15 pounds) repetitively. When lifting 0-pound and 3-pound weights, the β of the left SMA and M1 increased significantly after cTBS (p < 0.05). Also, the random intercepts of individual subjects increased significantly in the left SMA, left M1, and right SMA, but the slopes were not significantly affected by cTBS. Data also showed a significant positive correlation between the intercept of left M1, right SMA&M1 areas and age (all p < 0.05). Despite cTBS-induced inhibition, the supplementary motor area (SMA) exhibited enhanced fNIRS responses to increased loads, and the positive correlation between load inertia and motor-cortical activation remained unaltered.

Summary The modeling and prediction of drillstring dynamics have always been an essential portion of drilling engineering. As an emerging numerical simulation technique in recent years, the discrete element method (DEM) has been widely applied to wellbore stability evaluation and reservoir fracture reconstruction. In this paper, we propose a new framework for analyzing the dynamics of drillstring based on DEM and the theory of Timoshenko beam. First, a 3D Timoshenko beam bond model (TBBM) is derived in the framework of DEM, on the basis of which the drillstring-particle circular hypothesis and Rayleigh damping are integrated to formulate the dynamical coupling scheme. Bit-rock interaction, eccentricity, gravity, drillstring-wellbore contact, and joints are defined within this framework. The numerical accuracy of the TBBM is fully discussed and verified in five different static/dynamic tests, in which the computational error of the TBBM can even be minimized to 0.00116% in some specific scenarios. Simulations under various combinations of weight on bit (WOB) and rotational speed (RS) are conducted for horizontal gas well drilling configurations and the corresponding drilling experiment bench to analyze the kinetic behavior of the drillstring under practical conditions. The deformation, frequency, and stress distribution characteristics of the drillstring under transverse vibration are emphasized. In addition, unexpected stick/slip vibration modes of the bit are observed. The results illustrate that the DEM-based framework for drillstring dynamics provides new insights into vibration detection and potential drilling failures that may be further utilized for drilling tool optimization and real-time drilling control.

The near-Earth objects are not only important for studying the early formation of the Solar System, but also pose a serious hazard to humanity since they can make close approaches to the Earth. The study of their physical properties can provide useful information on their origin, evolution and hazard to human being. However, it is still challenging to investigate the newly discovered small near-Earth objects because of their limited observational window. We aim to derive the visible colors of near-Earth asteroids and perform an initial taxonomic classification to analyze their relationship with size or orbital parameters. Observations were performed using the Yaoan High Precision Telescope and the 1.88m telescope at the Kottamia Astronomical Observatory in broadband BVRI Johnson-Cousins photometric system. We present new photometric observations for 84 near-earth asteroids, and taxonomical classification of 80 of them based on their photometric colors. Our results show that nearly half (46.3%) of the objects in our sample are classified as S-complex members, 26.3% as C-complex, 6% as D-complex and 15.0% as X-complex; the remaining belong to the A- or V-type. Additionally, we identified three P-type NEAs in our sample according to the Tholen scheme. The fractional abundances of the C/X-complex members with H ≥ 17.0 were more than twice as large as those with H < 17.0. However, the fractions of C- and S-complex members with D ≤ 1km and D > 1km remains nearly the same, while X-complex members tend to have sub-kilometer diameters. In our sample, the C/D-complex objects are predominant among those with a Jovian Tisserand parameter of TJ < 3.1. These bodies could have a cometary origin. C- and S-complex members account for a considerable proportion of potentially hazardous asteroids.

Abstract The leakage flow through a traditional labyrinth seal reduces the compressor capacity of an oil-free magnetic bearing centrifugal compressor. Also, the super-heated leakage flow pollutes the downstream coolant flow, affecting motor cooling. A novel design is introduced to utilize the pressure loss across the seal by injecting liquid refrigerant near the seal inlet. The liquid-injected seal also functions as an expansion valve, producing low-temperature wet vapor at the seal exit. The wet vapor is projected to be utilized for motor cooling. A multiphase numerical simulation is performed to quantify the compressor performance of the liquid-injected seal and traditional seal under adiabatic conditions. The numerical simulation utilizes a Eulerian-Eulerian approach with an equilibrium phase change model. This study evaluates the compressor performance at three-speed lines: N1, N2, and N3. The base case results are validated with the experimental findings, with a maximum error of 3% in compressor efficiency. The local distribution of vapor mass fraction, pressure, and temperature are analyzed. The numerical results show that the leakage flow in the liquid-injected seal is reduced by 95%, and the compressor capacity is increased by 2.9%.

Abstract The necessity for more efficient, adaptable, and environmentally friendly systems is ever-increasing, especially in the HVAC industry. One of the main focuses in this area is the development of novel refrigerants. Therefore, designing and adapting HVAC systems to novel refrigerants is an essential step to comply to new marketing and regulatory demands. In this work, the performance of an oil-free centrifugal compressor is investigated with a new refrigerant: R1234YF. The analysis is carried out numerically with CFD modelling with an existing oil-free, magnetic bearing centrifugal compressor. The model is validated across different speedlines with experimental test data utilizing the working fluid for which the compressor was originally designed: R1234ZE. The validated model is investigated with R1234YF across the whole operating range with focus on the aerodynamic results, such as pressure ratio and isentropic aerodynamic efficiency. The analysis reveals that the use of R1234YF as a working fluid leads to the ability for higher lift and lower power consumption when compared to R1234ZE, albeit at a reduction of cooling capacity. A close inspection of the thermodynamic properties of R1234YF and R1234ZE was carried out, showing a reduction in speed of sound and density for R1234YF compared to R1234ZE at similar condenser and evaporator temperatures. The perspectives for the employment of R1234YF on the compressor is discussed, highlighting the flexibility that the refrigerant provides with regards to the compressor application, as it allows the compressor to operate in regions with lower evaporator temperatures or higher condenser temperatures.

ABSTRACT: The lack of well logging data and formation core samples in non-target complex intervals poses a challenge to traditional rock mechanics evaluation methods that rely on conducting laboratory experiments using core samples. In this study, we first characterize the microstructure of drilling cuttings and utilize image processing algorithms for denoising, boundary extraction, and boundary fitting of the microscopic images, achieving the digital representation of formation rocks. Finally, by assigning mechanical parameters to the digital model of formation rocks, the equivalent stress-strain curves of rocks are simulated using finite element analysis, enabling the rock mechanics evaluation of formation rocks based on drilling cuttings. The method established in this study overcomes the limitations of traditional rock mechanics evaluation methods that rely on formation core samples. It achieves the digital representation of formation rocks, enriches the methods for rock mechanics evaluation, and can serve as the basis for conducting research on engineering problems related to rock mechanics, such as formation fracturing, hydraulic fracturing, and wellbore stability, using digital twin technology.

ABSTRACT: In the process of hydraulic fracturing, hydraulic fractures can activate natural fractures and form a complex fracture network, but the opening of natural fractures needs to reach a certain threshold pressure (i.e., opening pressure). In ultra-deep reservoirs, the width of hydraulic fractures is small. If the flow friction of fracturing fluid in hydraulic fractures is ignored, the calculation of opening pressure will bring large errors. In this study, the opening pressure was calculated considering the combined effect of the friction along the hydraulic fractures and the local in-situ stress of the natural fracture. A mathematical model of natural fracture opening pressure considering the flow friction is proposed. Through the example calculation and analysis, it is found that the opening pressure of ultra-deep natural fractures is most affected by the width of hydraulic fractures, and due to the high stress difference, natural fractures are easier to be opened by shear slip. The longer the hydraulic fracture and the narrower its width, the greater the friction of the fracturing fluid along its path, which leads to a higher opening pressure for natural fractures. The high viscosity of the fracturing fluid and the large flow rate also increase the opening pressure of the natural fracture.

Background: Acute kidney injury (AKI) is a prevalent and severe medical condition that is frequently observed in the intensive care unit (ICU). Although numerous biomarkers have been identified to predict the prognosis of AKI, the lactate dehydrogenase to albumin ratio [LDH/ALB ratio (LAR)] has not been extensively investigated. The principal objective of this study was to assess the relationship between LAR and all-cause mortality in patients with AKI. Methods: A total of 6,831 AKI patients were included in this study, divided into survival (n = 5,152) and non-survival groups (n = 1,679). The association between LAR and mortality was examined through restricted cubic spline (RCS) analysis and Cox regression analysis. Subgroup analysis was used to search for interactive factors. Additionally, the prognostic capability of LAR was further evaluated using receiver operating characteristic (ROC) curve analysis. Results: for non-linearity < 0.001). A LAR of 10.4 was used as the cutoff point to generate the high-LAR and low-LAR subgroups, and the Kaplan-Meier curves revealed that the ICU cumulative survival rate for patients with AKI was significantly lower in the high-LAR group (log-rank p < 0.001). The LAR's prediction of ICU mortality in AKI patients yielded an area under the ROC curve of 0.65. Conclusion: Our research suggests that LAR monitoring may be promising as a prognostic marker among patients with AKI. Higher LAR is associated with greater ICU mortality.

Abstract The relationship between the microstructure of the ring forging and the ultrasonic anomalies were studied in response to the localized anomaly observed during the non-destructive testing of TA15 titanium alloy ring forging. The distribution of internal defects was explored through water immersion ultrasonic testing of ring forging. The microstructure of the normal region and the abnormal zone were compared using scanning electron microscopy and electron backscatter diffraction techniques. And finite-element simulation was used to simulate the formation process of the abnormal ultrasound position. The results showed that the different layers of the ring-forged component exhibited varying degrees of bottom wave attenuation along the radial direction. The abnormal area corresponded to a higher number of primary α-phase and larger grain sizes. Under the combined effect of temperature and stress, the recrystallized grains began to grow abnormally, leading to significant bottom wave attenuation.

In this study, we compared the effects of light from a high‐end LCD TV and an OLED TV on humans by measuring the saliva melatonin levels and the heart rate variability (HRV) during and before/after watching TV in the evening with 40 volunteers. Participants using the LCD TV demonstrated a decreased melatonin secretion by 2.7% after watching TV, whereas those utilizing the OLED TV exhibited an increase of 8.1%. The HRV analysis, which represents the relative activation levels of the sympathetic and parasympathetic nerves, revealed that on average, the OLED TV activated the parasympathetic nerves more than the LCD TV during the entire watching time. This indicates that watching OLED TVs induces relatively comfortable states. Further, a questionnaire was simultaneously conducted to assess eye discomfort and overall eye strain after watching TV, and the results showed a significantly increased eye fatigue after watching the high‐end LCD TV compared to the OLED TV.

Abstract This study explores the design issues of a learning-based approach to solving a tri-finger robotic arm manipulating task, which requires complex movements and coordination among the fingers. We train an agent to acquire the necessary skills for proficient manipulation by employing reinforcement learning. To enhance the learning efficiency, effectiveness, and robustness, two knowledge transfer strategies, fine-tuning and curriculum learning, are utilized and compared within the soft actor-critic architecture. Fine-tuning allows the agent to leverage pre-trained knowledge and adapt it to new tasks. Several tasks and learning-related factors are investigated and evaluated, such as model versus policy transfer and within- versus across-task transfer. To eliminate the need for pretraining, curriculum learning decomposes the advanced task into simpler and progressive stages, mirroring how humans learn. The number of learning stages, the context of the subtasks, and the transition timing are examined as critical design parameters. The key design parameters of two learning strategies and their corresponding effects are explored in context-aware and context-unaware scenarios, allowing us to identify the scenarios where the methods demonstrate optimal performance, derive conclusive insights, and contribute to a broader range of learning-based engineering applications.

A numerical analysis model for sand-mudstone interbedded fracturing based on field application in South China is presented in this paper. The proposed model can analyze the influence laws of different longitudinal lithology changes, stress difference changes, different interlayer positions, and fracturing fluid construction parameters on fracture characteristics. Based on the study of fracture characteristics of low-modulus mudstone, a set of layered stress loading experimental devices was independently designed and developed. Experimental analysis shows that the stress difference has a limited limiting effect on the interlayer propagation of hydraulic fracturing fractures in the Weizhou Formation, and the fracture height is prone to interlayer propagation. The injection of high-rate and high-viscosity fracturing fluid has a significant impact on the hydraulic fracture surface penetration. Numerical simulation analysis shows that the smaller the elastic modulus of the mudstone interlayer and the lower the minimum horizontal principal stress compared to the sandstone layer, the more favorable it is for fracture propagation. Field application showed that the highest injection rate of the fracturing pump in well A was 7 m3/min for south-west Weizhou oilfield shale oil. The interpretation results of the acoustic logging after fracturing showed obvious response characteristics of the formation fractures, and the farthest detection fracture response well distance was 12 m, indicating a good fracturing transformation effect and providing technical support for subsequent offshore shale oil fracturing construction.

Summary Harmful vibrations significantly impact drilling efficiency by reducing the rate of penetration (ROP) and shortening the service life of the drillstring and associated drilling tools. However, how vibrations influence drilling speed in the absence of tool damage remains unclear. Severe lateral vibrations, commonly known as a whirl, are considered the most detrimental type of vibration. Current research on drillstring whirl predominantly focuses on its dynamics and implications for drillstring safety. Although field practices suggest a strong relationship between ROP and the whirl types exhibited by the drillstring, publicly available studies addressing this connection remain limited due to a lack of research methods. Therefore, the relationship between the whirl state and ROP is investigated in this paper based on an integrated dynamic model, and its influencing mechanism is also revealed. One intriguing phenomenon is that, beyond the three commonly recognized whirl types, the drillstring can also exhibit a nonrevolution motion, consistent with the earlier hypothesis of rotation devoid of orbital movement. Under the model parameters used in this study, when the friction coefficient between the drillstring and the borehole wall is 0.05 and the mass eccentricity is 0.5 cm, the drillstring remains in this nonrevolution motion. Increasing the mass eccentricity to 2.50 cm transitions the drillstring to a forward whirl state. And, raising the friction coefficient to 0.20 induces a backward whirl state. When both parameters are adjusted simultaneously to 0.15 and 1.50 cm, respectively, the drillstring enters an irregular motion state. The most significant contribution of this study lies in the first-time observation in numerical simulation results that ROP decreases from 26.90 to 20.90 m/hr when the drillstring transitions into a state of backward whirl, along with an explanation of the underlying causes for this phenomenon. This is due to the increase in friction between the drillstring and the wellbore, resulting in a decrease in real weight-on-bit (RWOB) which is the axial interaction force between the drill bit and the rock. Because the normal contact force between the drillstring and the wellbore is caused by centrifugal force, the higher the rotational speed, the greater the normal contact forces become. This is verified by the ratio of ROP corresponding to nonbackward and backward whirl at three different rotation speeds, 60, 86, and 120 rev/min.

Deep-sea fisheries depend on various fishing methods, including trawling, purse seining, and longline fishing, among others. Studying the dynamic characteristics of trawling operations is essential for the trawl mechanism. Because of the solid truss support, the beam trawl system may be employed in extreme sea conditions, the high-speed driving of tugs, and maneuvering situations. This study systematically investigates the dynamic responses and structural safety of a midwater beam trawl during towing via the lumped mass method and OrcaFlex 9.7e simulations. Firstly, a trawl model with four towlines was developed and validated against flume tank experiments. Secondly, multiple operational scenarios were analyzed: towing speeds, angular velocity variations under a fixed turning radius, and radius effects under constant angular velocity. The results show that line tension increases with the speed increment and that the rigid frame destabilizes at angular velocities exceeding 20°/s due to centrifugal overload. Furthermore, line fracture scenarios during startup and straight-line towing were emphasized. Single-line failure leads to edge constraint loss, redistributing stress to the remaining lines, and asymmetric dual-line fracture triggers net torsion, reducing fishing efficiency. This study provides theoretical guidance for optimizing the safe operational parameters of midwater beam trawls.

Abstract Mn metal has become a highly promising candidate anode of aqueous batteries due to its high abundance, non‐toxicity, relatively low redox potential, and large theoretical capacity. However, the development of Mn ion batteries (MIBs) is hindered by controversies over reaction mechanisms, metal hydrogen evolution reactions, and poor conversion efficiency. Therefore, a further comprehensive study is urgently desired for its research and application. In this work, a V 2 O 5 bilayer structure is innovatively constructed by introducing stripping agents (H 2 O and Ni 2+ ) to form stable “Ni─O” columns, which not only enhances the stability of the structure but also effectively blocks interlayer corrosion. The preferential orientation and the excellent interlayer spacing d (001) = 10.28 Å broads Mn 2+ diffusion channels. In this way, the sites for ion storage are also increased by creating abundant vacancies, accelerating the diffusion rate of ions in the modified V 2 O 5 (Ni 0.48 V 2 O 5 •0.90H 2 O, NiVO) lattice. The co‐storage mechanism of Mn 2+ /H + ions effectively alleviates the limitations of high charge density and large solvation ion radius. Furthermore, the storage mechanism and structural evolution process are investigated via analytical chemistry. These findings provide new ideas for designing new positive electrode materials and effectively promote the progress of the MIB research and application.

Polycrystalline silicon (poly-Si) carrier-selective passivating contacts (CSPCs), featuring high photoconversion efficiency (PCE) and cost-effectiveness, have emerged as a promising approach for high-efficiency crystalline silicon (c-Si) solar cells. To minimize parasitic absorption losses induced by doped poly-Si window layers, wide bandgap oxygen-alloyed poly-Si (poly-SiO x ) layers are developed. However, challenges persist in achieving excellent surface passivation for boron-doped poly-SiO x contact stacks, likely caused by boron diffusion during annealing and the reduced doping concentration resulting from lower crystallinity as oxygen content increases. In this study, we investigate the impact on the passivating contact structure and solar cell performance of a 10-nm thick intrinsic hydrogenated amorphous silicon buffer layer with varying oxygen content (a-Si (O x ):H) deposited by plasma-enhanced chemical vapor deposition (PECVD), and placed between the tunneling silicon oxide (SiO x ) and the poly-SiO x ( p + ). After the hydrogenation step, we obtain both high passivation quality with implied open circuit voltage (i V oc ) of 728.3 mV and low contact resistivity ( ρ c ) of 59.18 mΩ cm 2 on polished surface for oxygen-free a-Si:H buffer layer. These improvements can be attributed to the appropriate thickness of the tunnel oxide and confirmed by transmission electron microscopy (TEM) images, to higher crystallinity of the buffer layer, which facilitates more efficient doping in the buffer layer. This is evidenced by energy dispersive X-ray spectroscopy (EDX), and X-ray photoelectron spectroscopy (XPS) results. At the device level, a front-side textured, rear-side flat, rear junction poly-SiO x /poly-SiO x solar cell on n-type c-Si wafer, an efficiency improvement can be observed from 3.55 % without a PECVD buffer layer to 18.9 % with an oxygen-free a-Si:H PECVD buffer layer. The impact of the buffer layer crystallinity on cell performance is further demonstrated by deploying a 10-nm thick LPCVD buffer layer, which facilitates an efficiency of 21.15 % for the same device structure. • Inserting a 10-nm buffer layer can enhance passivation and lower resistivity. • Gains are from better crystallinity, dopant distribution, and SiO x layer control. • Achieving an efficiency of 18.9 % with oxygen-free buffer in FBC solar cells. • An LPCVD buffer layer with higher crystallinity shows 21.15 % efficiency.

Abstract Design Science is the discipline that studies the creation of artifacts – products, services, and systems and their embedding in our physical, virtual, psychological, economic, and social environments. This editorial is a collective effort of the Design Science Journal’s editorial board members, past and present. The journal’s inaugural 2015 editorial, “Design Science: Why, What and How,” reflected the thoughts and vision of that first editorial board for the new journal and the discipline it represented. The present contribution offers the reflections of editors who served the journal in the past 10 years. The individual contributions were not primed and are presented here unedited for conformity or consistency. Differently from the 2015 editorial, there is no effort to synthesize the individual contributions, leaving the task to our readers, who can draw their own conclusions about the Design Science Journal and community accomplishments to date, and the challenges ahead.

In this study, a molecularly imprinted electrochemical sensor was constructed based on the graphene quantum dots-gold nanoparticles and it was successfully applied in the ultrasenstitive detection of 17β-estradiol.

In order to avoid image distortion caused by excessive processing during image detail enhancement, an image detail enhancement method for cultural and creative product packaging design based on improved guided filtering was proposed. Obtain the packaging design image of cultural and creative products, use the improved non-local mean filtering algorithm to denoise the image, and repair the bad points in the image to protect important details. The multi-scale guidance filter is introduced to improve the guidance filter, and the multi-scale guidance filter is used to enhance the details of the modified image. The experimental results show that the minimum peak signal-to-noise ratio of the image enhanced by this method can reach 53.2 db, with the entropy value 0.94 and the minimum average contrast of the image can reach 0.85, indicating that the image processed by this method has high quality and high detail retention rate.

In view of the rolling bearing fault signal non-stationarity, strong noise can lead to low fault diagnosis accuracy. A Swin Transformer and generalized S Transform fault diagnosis method is proposed to solve the problems of difficult signal feature extraction and low diagnostic accuracy. Generalized S transform is used to improve the resolution of bearing fault signals, the Swin Transformer model is used to master the shallow weight required for identifying rolling bearing faults for highly fault characteristic expression signals, and the deep weight is obtained by backpropagation training. Finally, the extracted features are input into the improved Softmax classifier for fault classification. The various signal processing methods for the bearing signal processing ability are compared, and this model’s diagnosis ability and the ability to resist noise are verified. The experimental results show that the method has a remarkable ability and an accuracy of above 90% in the anti-noise test and also has a good robustness.

Mastoparans (MP), a class of α-helix cationic insect-derived antimicrobial peptides, have a broad spectrum of biological activities including inhibiting bacteria, fungi, viruses, and parasites. Amino acid substitution, peptide modification, peptide chain cyclization, and dosage form modification can enhance the biological activities and target and reduce the toxicity of mastoparans. In this review, we summarize the structure, biological function and modification methods of mastoparans, and prospect the development of antibacterial drugs based on mastoparans, so as to provide reference for the research of mastoparans as a new antibacterial drug.

In business process reengineering, engineering approaches to realize effective business processes have been studied in an interdisciplinary manner involving researchers in management, sociology, and other fields. Predicting design effectiveness, identifying effective design parameters and their settings, and selecting the optimal design are essential to realize effective business processes. Therefore, the objective of this paper is to demonstrate that the method with agent-based models and simulation can assist designers’ decision-making and provide necessary knowledge through a case study of business process design for both cyclic and acyclic demand fluctuations. The case study was conducted on an IT systems department business process of a company that processes 50 demands with different demand fluctuation types. The simulation model described the demands and corresponding operations in a hierarchical manner to reduce the complexity of the design description. 16 design scenarios were prepared by combining 4 design parameters. The case study examined the problems of how the proposed method could provide knowledge regarding selection of optimal design scenarios, effective design parameters and their settings, and causal relationships of design parameter changes and effects. The case study results confirmed that our proposed method can provide useful knowledge. For example, that two specific design parameters have a synergistic effect, and that the effect of changing the design parameter of teaming is not caused by teaming itself, but the communication-work reduction that results from teaming, were provided. The results demonstrated that the proposed method could assist designers’ decision-making and provide them with necessary knowledge in designing business processes.

With the increasing demand for underwater environment monitoring and remote object identification, underwater object detection algorithms based on forward-looking sonar images have become a research hotspot. A kind of algorithm called remote deep feature fusion detection network (RDFFRN) is proposed, which aims to solve the problems of object shadow and background confusion and low detection accuracy of small objects in the underwater object detection algorithm of sonar images. First, the model proposes the deep feature extraction and fusion module (DFEFM). It achieves more multilayered feature fusion and captures more local details. Finally, the RDFFRN proposes a new head detection network, which increases the proportion of small-sized feature maps and improves the model’s discrimination ability for small underwater objects. After extensive experiments on a sonar images dataset, the RDFFRN is verified to be superior to other object detection methods. The RDFFDN improves the mean average accuracy by 3.2% over the baseline model. It can be shown that RDFFRN has a broad application prospect in the underwater operation field.

[This corrects the article DOI: 10.1016/j.csbj.2024.04.024.].

Transition metal oxide (TMO) thin films exhibit large bandgap and hold great potential for enhancing the performance of silicon heterojunction (SHJ) solar cells by increasing the short-circuit current density significantly. On the other hand, achieving precise control over the electrical properties of TMO layers is crucial for optimizing their function as efficient carrier-selective layer. This study demonstrates a general and feasible approach for manipulating the quality of several TMO films, aimed at enhancing their applicability in silicon heterojunction (SHJ) solar cells. The core of our method involves precise engineering of the interface between the TMO film and the underlying hydrogenated intrinsic amorphous silicon passivation layer by managing the reaction of the TMO on the surface. X-ray photoelectron spectroscopy spectra demonstrate that our methods can modify the oxygen content in TMO films, thereby adjusting their electronic properties. By applying this method, we have successfully fabricated WO x -based SHJ solar cells with 23.30 % conversion efficiency and V 2 O x -based SHJ solar cells with 22.04 % conversion efficiency, while keeping n -type silicon-based electron-transport layer at the rear side. This research paves the way for extending such interface engineering methods to other TMO materials used as hole-transport layers in SHJ solar cells. • Controlling the TMO/( i )a-Si:H interface using three methods: noPT, PT, and PTB. • PT method preserves oxygen content in TMO layers better than PTB and noPT methods. • PTB method maintains optimal TMO oxygen content regarding conversion efficiency. • PTB method enables 23.30 % efficiency and 80.80 % FF in WO x -based SHJ solar cells. • PTB method enables 22.04 % efficiency and 74.88 % FF in V 2 O x -based SHJ solar cells.