Indirect Method Research Articles

Real-Time Co-optimization of Gear Shifting and Engine Torque for Predictive Cruise Control of Heavy-Duty Trucks

Fuel consumption is one of the main concerns for heavy-duty trucks. Predictive cruise control (PCC) provides an intriguing opportunity to reduce fuel consumption by using the upcoming road information. In this study, a real-time implementable PCC, which simultaneously optimizes engine torque and gear shifting, is proposed for heavy-duty trucks. To minimize fuel consumption, the problem of the PCC is formulated as a nonlinear model predictive control (MPC), in which the upcoming road elevation information is used. Finding the solution of the nonlinear MPC is time consuming; thus, a real-time implementable solver is developed based on Pontryagin’s maximum principle and indirect shooting method. Dynamic programming (DP) algorithm, as a global optimization algorithm, is used as a performance benchmark for the proposed solver. Simulation, hardware-in-the-loop and real-truck experiments are conducted to verify the performance of the proposed controller. The results demonstrate that the MPC-based solution performs nearly as well as the DP-based solution, with less than 1% deviation for testing roads. Moreover, the proposed co-optimization controller is implementable in a real-truck, and the proposed MPC-based PCC algorithm achieves a fuel-saving rate of 7.9% without compromising the truck’s travel time.

A Comprehensive Study on Methane Adsorption Capacities and Pore Characteristics of Coal Seams: Implications for Efficient Coalbed Methane Development in the Soma Basin, Türkiye

Abstract This study represents a comprehensive assessment of methane adsorption capacity and pore characteristics for the coal seams of the Soma Basin in Western Türkiye, with a focus on their implications for coalbed methane potential. Twenty-one exploration wells were utilized to obtain coal samples from the kP1 and kM2 coal seams in the Kınık coalfield of the Soma Basin. High-pressure methane adsorption experiments using the indirect gravimetric method were conducted to quantify the storage capacities of these coal seams. Results revealed a wide range of methane adsorption capacities, ranging from 10.5 to 28.3 m3/t (air-dry basis), indicating significant methane storage potential for the kP1 and kM2 coal seams. The gas contents, ranging from 1.1 to 4.3 m3/t (as-received basis), suggested that the coal seams were undersaturated. Low-pressure N2/CO2 adsorption tests, along with standard proximate and gross calorific value analyses, were performed to investigate the influence of coal quality and pore characteristics on methane adsorption capacities. The findings demonstrated correlations between coal quality parameters and adsorption capacity, with ash yield showing a moderately negative correlation and fixed carbon content and gross calorific values exhibiting moderately positive correlations. Microporosity was identified as the critical factor governing methane adsorption, with a strong positive correlation observed between micropore surface areas and volumes and adsorption capacity. These results highlight the significant methane storage capacities of the coal seams in the Soma Basin and underscore the importance of micropores in determining methane adsorption capacity. The findings provide valuable insights for optimizing methane extraction and utilization in the region and offer important considerations for reservoir characterization and development strategies in similar low-rank coal deposits. Highlights Extensive evaluation of methane adsorption and pore characteristics in Soma Basin coals, uncovering substantial potential for coalbed methane. The study reveals a diverse range of methane adsorption capacities, indicating highly promising methane storage capabilities. Correlation between coal quality parameters and methane adsorption, offering valuable insights into gas storage influenced by coal composition. Emphasis on the crucial role of micropores in methane storage, underscoring their significance as primary adsorption sites. Practical implications for optimizing methane extraction and utilization, guiding reservoir development in low-rank coal deposits like Soma Basin.

Comparison of time-domain and frequency-domain models for vibration prediction of a rail transit viaduct paved with floating slab track

Noise from rail transit viaducts often has a negative effect on surrounding buildings and nearby residents. To reduce the bridge vibration and radiated noise, floating slab tracks have been widely adopted in rail transit viaducts. To calculate the vibration of coupled track-bridge systems, both time-domain and frequency-domain methods can be applied although their relative performance is not very clear. This study aims to compare the two approaches and then provide some guidelines in choosing the appropriate method for predicting the vibration. The principle and methodology of the two calculation methods are firstly introduced, and the models for the train, floating slab track and bridge are developed using similar parameters. To further improve the efficiency and accuracy of the frequency-domain method, a half period method and a weighted average method are proposed to calculate the average responses of a certain point on the rail, floating slab and bridge to approximate the response during the pass-by. An indirect method is used to estimate the wheel–rail combined roughness from the measured rail acceleration when the train is running on the bridge, and compared with the direct measurement rail roughness. For the vibration of the bridge and floating slab, comparisons are made between results obtained from the time-domain and frequency-domain methods with different train speeds, and between results from experiment and simulation with different roughness. It is found that the wheel–rail contact forces and other structural responses from the two approaches show good consistency in the frequency region above 20 Hz. It is shown that a good approximation of the response during the pass-by can be obtained using the frequency-domain method by adopting the half period average or a simplified weighted average of two wheel position cases. When using the measured roughness and estimated roughness, the simulated vibration of the floating slab and bridge match well with the experimental results, and the indirect method can be used to modify direct measurement roughness in lower frequency regions. In the vibration prediction, the rail vibration or roughness, and other parameters in the vehicle–track–bridge system, should be measured accurately to ensure high reliability.

Prediction of rolling resistance and wheel force for a passenger car tire: A comparative study on the use of different material models and numerical approaches

In this research, the characteristics of tire-road interaction of a 185/65R14 88H passenger car tire are investigated using the Finite Element Method in Abaqus commercial software. Moreover, the effect of various material models on tire performance is studied by implementing Visco-Hyperelastic, Parallel Rheological Framework, and Mullins effect. The novelty of this research is devoted to the development of the complex material models particularly considering the Mullins effect of the rubber compounds in the tire structure for the load-displacement criteria. For this purpose, a tire finite element model was generated using Abaqus/Standard command line in two different methods including an Arbitrary Lagrangian-Eulerian formulation for steady state rolling and implementing a pure Lagrangian approach for the transient dynamic analysis carried out implicit and explicit process respectively. Rolling resistance force was computed according to ISO 28580 with 210 kPa inflation pressure and 4155 N vertical load. The footprint test results were extracted in both static and transient dynamic analyses. Additionally, the wheel reaction force was predicted using an indirect method by extracting the tire-terrain contact patch reaction force in Abaqus/Explicit to observe the effect of the material convection along with stress softening phenomena of the rubber compounds of tire structure. In the post-processing analysis, the wheel reaction was filtered by implementing SAE60 filter to reduce the numerical noise in the final response.

A method for hierarchical weighted fitting of regular grid DSM with discrete points

Abstract. A Digital Surface Model (DSM) is a crucial spatial geographic information data used to describe the shape of the earth’s surface in Geographic Information Systems (GIS). DSM is the core data used in terrain analysis in GIS. A regular grid DSM is generally generated by interpolating a large number of discrete point clouds. This paper proposes a method of using a hierarchical weighted strategy to fit a regular grid DSM with discrete points. This method uses a pyramid hierarchical strategy to refine the target regular grid from one grid with finer parameters of 3*3, until the nth level (the interval of the grid is equal to the expected interval), and then gradually places the discrete point cloud into the corresponding grid by weighted averaging, and uses the result of this level as the initial value of the next level. This algorithm can avoid the problem of low efficiency in retrieving a large number of discrete point clouds, and the indirect interpolation method not considering the contribution of distant neighboring point clouds. The operation of point cloud data is a stream operation, which does not require consideration of the topological information of point clouds, and has simple operation and no additional memory consumption. It is especially suitable for the production of regular grid DSM with massive point clouds. To verify the effectiveness of this method, the article selected six typical terrain data such as high mountains, mountains, hills, plains, urban areas, and lakes for experiments. The results show that compared with the construct-TIN method for producing DSM, this method has very good processing accuracy and processing efficiency.

Developing Polymeric Carbon Nitrides for Photocatalytic H2O2 Production.

Hydrogen peroxide (H2O2) plays a crucial role in various applications, such as green oxidation processes and the production of high-quality fuels. Currently, H2O2 is primarily manufactured using the indirect anthraquinone method, known for its significant energy consumption and the generation of intensive by-products. Extensive research has been conducted on the photocatalytic production of H2O2via oxygen reduction reaction (ORR), with polymeric carbon nitride (PCN) emerging as a promising catalyst for this conversion. This review article is organized around two approaches. The first part main consists of the chemical optimization of the PCN structure, while the second focuses on the physical integration of PCN with other functional materials. The objective is to clarify the correlation between the physicochemical properties of PCN photocatalysts and their effectiveness in H2O2 production. Through a thorough review and analysis of the findings, this article seeks to stimulate new insights and achievements, not only in the domain of H2O2 production via ORR but also in other redox reactions.

Experimental evaluation of Adsorption Heat for Water vapour/Silica gel pair for chiller application

Isosteric adsorption heat is crucial in assessing adsorption cycle performance. Typically, adsorption heat is indirectly estimated from the isotherm equation fitted to the experimental uptake data. This indirect method is susceptible to the accuracy and choice of isotherm equation. Consistency of this indirect method with actual adsorption heat measurements is rarely examined. Present work addresses this research gap by simultaneously measuring adsorption uptake and heat. This is achieved by incorporating heat flux sensors within an existing constant volume variable pressure (CVVP) setup. The measurements are carried out for water vapour/RD-silica gel pair with temperature and pressure ranging from 298 to 363 K and 0.15 kPa to 6.3 kPa respectively. Two popular isotherms viz. Dubinin–Astakhov (D–A) and Tóth isotherm equation are used to estimate the indirect adsorption heat. Both isotherm equations show a good fit with the experimental uptake (< 5% deviation). Interestingly, indirect adsorption heat estimated using Tóth isotherm fails to predict (∼15% deviation) the uptake dependent adsorption heat trend shown by calorimetric data, whereas D–A isotherm agrees well (<5% deviation). Therefore, the present work forms fundamental basis for identifying suitable isotherm equation, which is consistent with experimental adsorption uptake as well as heat data. Subsequently, a comparison of theoretical coefficient of performance (COP) for water vapour/RD-silica gel adsorption chiller is undertaken, based on indirect adsorption heat values available in the literature. The comparison reveals that COP prediction is sensitive to adsorption heat. This further emphasizes the necessity for experimentally measuring adsorption heat.

111 Current and future usage of soybean meal in swine diets in China

Abstract The objective of this presentation was to introduce the utilization tendency and research progress of soybean meal (SBM) in swine diets in China. As for the utilization tendency of SBM in China, it not only brings great pressure to the food security of China, but also directly pushes the high production cost of animal products. In 2022, 117 million tons of protein feed was consumed by the animal husbandry in China, accounting for nearly 1/3 of the total protein feed consumption in the world. Thus, the application of low-protein diet has been promoted with the strong support of the Ministry of Agriculture and Rural Affairs in China since 2018. With the related techniques, including popularizing low protein diet, developing new protein feed resources, promoting precise nutrition, and feeding technology, even though the compound feed output has increased by more than 84 million tons in 2022 in China, the SBM consumption in feed has reduced 6%. Recently, the geopolitical challenges, regional unrest and climate change tendency have increased the great uncertainty of protein feed supply, which requires us to deeply understand the significance of SBM reduction and substitution in animal feed. As for the research progress, the available energy contents of SBM were determined on growing pigs. Barrows [n = 24; initial body weight (BW) = 36 ± 1.4 kg] were randomly allotted to 4 diets containing SBM with either corn basal or corn-soybean meal basal, and total feces and urine collection method and indirect calorimetry method were used to determine the available energy of SBM. The results showed that the average digestible energy (DE), metabolizable energy (ME), net energy (NE), and retained energy (RE) values in SBM [17.36, 16.52, 10.62, and 5.06 MJ/kg dry matter (DM), respectively] determined using the corn-SBM-basal diet were not different from the those determined using the corn-basal diet. Moreover, the best fitted prediction equations developed based on 22 SBM samples produced from soybeans from China (n = 6), USA (n = 6), Brazil (n = 7) or Argentina (n = 3) were: DE = 38.44 - 0.43 CF - 0.98 GE + 0.11 ADF (R2 = 0.67, P &amp;lt; 0.01) and ME = 2.74 + 0.97 DE - 0.06 CP (R2 = 0.79, P &amp;lt; 0.01). The in vitro digestion kinetics of SBM from different sources showed that the release of amino acids in the 0-10 min time interval was significantly negatively correlated with the NE of SBM (R2 = -0.34).

Artificial neural network‐based adaptive control for nonlinear dynamical systems

SummaryThis research article presents an artificial neural network (ANN)‐based indirect adaptive control method for nonlinear dynamical systems. In this article, a modified Elman recurrent neural network (MERNN) is proposed as an identifier and controller for controlling nonlinear systems. The architecture of the proposed controller is a modified form of the existing Elman recurrent neural network. The parameter training of ANN‐based controllers is obtained by using the most popular optimization algorithm which is known as the back‐propagation algorithm. A comparative study includes Elman, Diagonal, Jordan, feed‐forward neural network (FFNN), and radial basis function network (RBFN)‐based controllers to compare with the proposed MERNN controller. To determine the controller's robustness, parameter variations, and disturbance signals have been considered. The performance analysis of the proposed controller is illustrated by two simulation examples. The simulation results reveal that MERNN can not only identify the unknown dynamics of the plant but also adaptively control it compared to the others.

Comparative analysis of the drugs efficacy for carbohydrate metabolism early disorders (prediabetes) treatment: A review

In the contemporary reality pharmacological correction of the early carbohydrate metabolism disorders is the main method for the type 2 diabetes prevention. Taking into account the main role of insulin resistance in the prediabetes development it can be supposed that pharmacological agents directly activating the insulin receptor are the pathogenic-base therapy for prediabetes treatment. Such kind of this pathogenic therapy is Subetta® – a representative of the class of biological drugs created using the based graduated technology. Due to the absent of the direct comparative trials of Subetta® versus metformin in the efficacy of the type 2 diabetes prevention in prediabetes patients, was performed an analysis of the effectiveness of these two drugs using the adjusted indirect comparison method of the results of the randomized double-blind placebo-controlled clinical trial of Subetta® efficacy and safety in impaired glucose tolerance patients with the results of several metformin studies similar in inclusion and efficacy criteria. The results indicate greater Subetta® efficacy in the treatment of glucose intolerance and metformin's – in the impaired fasting glucose treatment, which can be explained by the differences in the action mechanisms of these two drugs for prediabetes treatment.

Porphyromonas gingivalis OMVs promoting endothelial dysfunction via the STING pathway in periodontitis.

This study aimed to assess the effects of Porphyromonas gingivalis outer membrane vesicles (Pg-OMVs) in chronic periodontitis and explore the underlying mechanism involved. In vitro, Pg-OMVs were incubated with Ea.hy926 (vessel endothelial cells, ECs) to evaluate their effects on endothelial functions and to investigate the underlying mechanism. The effects of endothelial dysfunction on MG63 osteoblast-like cells were verified using an indirect co-culture method. For invivo studies, micro-CT was conducted to identify alveolar bone mass. Immunofluorescence staining was conducted to confirm the levels of stimulator of interferon genes (STING) in the blood vessel and the number of Runx2+ cells around the alveolar bone. Pg-OMVs were endocytosed by ECs, leading to endothelial dysfunction. The cGAS-STING-TBK1 pathway was activated in ECs, which subsequently inhibited MG63 migration and early osteogenesis differentiation. Invivo, Pg-OMVs promoted alveolar bone resorption, increased STING levels in the blood vessel, and decreased Runx2+ cells around the alveolar bone. Pg-OMVs caused endothelial dysfunction and activated the cGAS-STING-TBK1 signal cascade in ECs, thereby impairing ECs-mediated osteogenesis. Furthermore, Pg-OMVs aggregated alveolar bone loss and altered the blood vessel-mediated osteogenesis with elevated STING.

Electrical measurement method of static friction force on rough surface

Friction plays a key role in the assessment of the safety and stability of mechanical systems (such as superconducting magnet quench explosion, aerospace vehicle bearing wear, etc.). Due to the closeness of the interfaces in engineering structures and the randomness of the contact surfaces, existing methods for measuring static friction force are unable to measure it at the contact interfaces of engineering structures under service conditions. In this paper, a new method for measuring the static friction force at the interface based on electrical signals is proposed. This method enables the measurement of the static friction force at interfaces of complex engineering structures under service conditions solely through electrical signals. The results indicate that the contact resistance gradually decreases with the increase in tangential load during the static friction stage until a monotonic behavior of macroscopic sliding occurs. The evolution of contact resistance is linked to the evolution of the real contact area, and this monotonic behavior can be explained as the deformation form of contact points. The accuracy of the proposed electrical measurement method is verified by comparison with experimental results (with an error of less than 9%). The indirect measurement method of friction force proposed in this paper can effectively measure the static friction force at the interfaces of engineering structures under service conditions, and it is expected to be applied to the detection of friction performance at engineering structure interfaces in extreme service environments.

Development of a Gaussia luciferase immunoprecipitation assay for detecting Schistosoma japonicum infection

Timely and accurate diagnosis of Schistosoma infection is important to adopt effective strategies for schistosomiasis control. Previously, we demonstrated that Schistosoma japonicum can secret extracellular vesicles and their cargos may serve as a novel type of biomarkers for diagnosing schistosomiasis. Here, we developed a Gaussia luciferase immunoprecipitation assay combined with S. japonicum extracellular vesicle (SjEV) protein to evaluate its potential for diagnosing schistosomiasis. A saposin-like protein (SjSLP) identified from SjEVs was fused to the Gaussia luciferase as the diagnostic antigen. The developed method showed good capability for detecting S. japonicum infection in mice and human patients. We also observed that the method could detect schistosome infection in mice as early as 7 days of post-infection, which showed better sensitivity than that of indirect ELISA method. Overall, the developed method showed a good potential for detecting Schistosoma infection particularly for early stage, which may provide an alternative strategy for identify Schistosoma infection for disease control.

Effectiveness of 13-valent pneumococcal conjugate vaccine for prevention of invasive pneumococcal disease among children in the United States between 2010 and 2019: An indirect cohort study

BackgroundA U.S. case-control study (2010–2014) demonstrated vaccine effectiveness (VE) for ≥ 1 dose of the thirteen-valent pneumococcal conjugate vaccine (PCV13) against vaccine-type (VT) invasive pneumococcal disease (IPD) at 86 %; however, it lacked statistical power to examine VE by number of doses and against individual serotypes. MethodsWe used the indirect cohort method to estimate PCV13 VE against VT-IPD among children aged < 5 years in the United States from May 1, 2010 through December 31, 2019 using cases from CDC’s Active Bacterial Core surveillance, including cases enrolled in a matched case-control study (2010–2014). Cases and controls were defined as individuals with VT-IPD and non-PCV13-type-IPD (NVT-IPD), respectively. We estimated absolute VE using the adjusted odds ratio of prior PCV13 receipt (1-aOR x 100 %). ResultsAmong 1,161 IPD cases, 223 (19.2 %) were VT cases and 938 (80.8 %) were NVT controls. Of those, 108 cases (48.4 %; 108/223) and 600 controls (64.0 %; 600/938) had received > 3 PCV13 doses; 23 cases (17.6 %) and 15 controls (2.4 %) had received no PCV doses. VE ≥ 3 PCV13 doses against VT-IPD was 90.2 % (95 % Confidence Interval75.4–96.1 %), respectively. Among the most commonly circulating VT-IPD serotypes, VE of ≥ 3 PCV13 doses was 86.8 % (73.7–93.3 %), 50.2 % (28.4–80.5 %), and 93.8 % (69.8–98.8 %) against serotypes 19A, 3, and 19F, respectively. ConclusionsAt least three doses of PCV13 continue to be effective in preventing VT-IPD among children aged < 5 years in the US. PCV13 was protective against serotypes 19A and 19F IPD; protection against serotype 3 IPD did not reach statistical significance.

Indirect Spectrophotometric Method Based on a Selective Reaction Between Bicinchoninic Acid and Copper(I) for the Determination of Metal Ions

Indirect Spectrophotometric Method Based on a Selective Reaction Between Bicinchoninic Acid and Copper(I) for the Determination of Metal Ions

Maglumi X3 fully automated chemiluminescent immunoassay for islet cell autoantibodies. Analytical performance and comparability to indirect immunofluorescence method

Maglumi X3 fully automated chemiluminescent immunoassay for islet cell autoantibodies. Analytical performance and comparability to indirect immunofluorescence method

Joint stress of a hinged platform composed of eight boxes

The box-type hinged platform has important applications in ocean engineering. In this paper, a multi-module assembled box-type platform is described. The mid-section load of the platform is numerically simulated based on the three-dimensional velocity potential theory and the indirect time-domain method through the hydrodynamic module AQWA in ANSYS. The stress of the hinged joints of platforms was performed using finite element analysis software in ANSYS software. The results show that: (1) In irregular waves, the shear force and bending moment in the middle section of the platform increases with the increase of the significant wave height; (2) Under the same towing scheme, the stress of the hinged joints between box platforms shows an increasing trend with the increase of wave level. Under the same wave working condition, the stress at the uniaxial nut of the hinged joints is relatively high, which is prone to fracture.

A Remaining Useful Life Indirect Prediction Method for Lithium-Ion Batteries Based on SA-DBN

To solve the issue that the battery capacity cannot be directly measured in practice, a more practical indirect remaining useful life (RUL) prediction method is proposed. First, the battery state characteristic parameters are analyzed and the time interval of equal discharge voltage drop (TIE-DVD) is selected as the indirect health factor. Second, the degradation relationship model is established by using back propagation (BP) neural network. Then, the deep belief network (DBN) model is used to establish the indirect health factor prediction model. Finally, to verify the adaptability of the proposed method to different types of batteries with different aging levels, both datasets from our own laboratory and the datasets from NASA Ames Research Center are used for experimental validations. The comparative experiments demonstrate that the proposed RUL prediction method is simple, accurate, and practical.

Seismic Response of Utility Tunnel in Trapezoidal Backfilled Soil Under P Wave and Amplification Effect of Ground Motion

ABSTRACT For the seismic risk of utility tunnel in trapezoidal backfilled soil and its possible amplification effect of ground motion, the seismic response of utility tunnel in trapezoidal backfilled soil under P wave is studied by a high-precision indirect boundary element method (IBEM) with the idea of “partition fit.” The results show that the peak surface displacement appears on the backfill surface, and the softer the backfilled soil, the greater the peak surface displacement; the peak vertical displacement at oblique incidence is generally smaller than that at vertical incidence; the existence of utility tunnel can restrain the incidence wave to a certain extent, especially for the low-frequency wave; the peak displacement and stress of utility tunnel in the soft backfilled soil are all greater than that in stiff backfilled soil; the peak stress of utility tunnel at oblique incidence is greater than that at vertical incidence; the stress concentration occurs at the axillary corner; and the stress in the inner wall of utility tunnel is greater than that in the outer wall. The similar conclusions could be further confirmed from the time history analysis. The research results can provide some reference for the seismic design of utility tunnel in the backfill site and the evaluation of seismic performance of near surface pipeline, etc.

Applying indirect reference interval method for the reference interval appropriateness assessment: A retrospective study from a medical center

Applying indirect reference interval method for the reference interval appropriateness assessment: A retrospective study from a medical center