Concave Areas Research Articles

Evaluation navigation controlled gate of aging spillway on cavitation damage.

High-speed flow of clean water or water with sediment released from aging spillways may cause abrasion and cavitation on the concrete surface gradually. The occurrence of irregularities on the concrete surface can exacerbate the erosion problem. Which might jeopardize the safety of dams constantly, hence the rehabilitation efforts become urgent tasks in dam safety projects. This study employs a 3D Computational Fluid Dynamics (CFD) model to quantitatively analyze the cavitation risk on the aging concrete surface of the Chay 5 spillway in Ha Giang, Vietnam, under various operation scenarios. There are two standards used to measure cavitation: the cavitation index (σ) which indicates the danger due to the drop of pressure in rapid flow, and the new gasification index (β) which takes into consideration the formation and collapse of bubbles behind asperities. Three extreme flood cases may not result in potential cavitation because both σ and β exceed critical thresholds. Regarding the six controlled gate scenarios with normal water level, the σ profiles are approximated 1,0 showing a low likelihood of cavitation damage while the β values are smaller than 0.8, indicating a considerable risk of cavitation. Besides, the opening height of 100 cm poses the greatest risk of creating severe cavitation erosion in the concave area and slope portion. The flip bucket experienced the most vulnerable cavitation when the opening height is 400 cm. In addition, an approach to spillway surface rehabilitation involving specialized mortars has been presented. For aging conveyance structure, gasification index (β) takes into account irregularities surface, providing a more comprehensive assessment of the likelihood of cavitation damage than cavitation index (σ). After rehabilitation with anti-shrinkage high abrasion resistance mortar, the entire spillway surface is smooth. This allows for reducing the cavitation risk and improvement of life service thereof.

Yunfuconcha new genus, a possible stem-archiheterodont bivalve from the Ordovician of Guangdong, South China

ABSTRACT Yunfuconcha bimenta, a new genus and species of bivalve from the Ordovician of western Guangdong, China, is described. Its unusual hinge consists of a palaeotaxodont-like dentition anteriorly and a heteroconch-like dentition posteriorly. The posterior hinge area exhibits a remarkable, broad, deeply inset, concave ligament area, which is reminiscent of the ventrally expanded ligament of some Recent and fossil lucinoids and the triangular resilifer in late Palaeozoic crassatellid heteroconchs. Lamellar posterior teeth and sockets complete the posterior dentition. The unusual combination of features, normally associated with either the Order Cardiolariatida (used here in place of Order ‘Afghanodesmatida’—the type genus Afghanodesma, is known only from wax impressions rendering it and its nominal higher taxa invalid) or various crassatelloids and lucinoids, make systematic placement of Yunfuconcha n. gen. uncertain below subclass rank. In view of presumed derived heteroconch-like characters of the posterior hinge, we place Yunfuconcha n. gen. in the Subclass Autobranchia, possibly as a stem archiheterodont or a stem heteroconch.

Analyzing the association between the hydrodynamics and bank erosion along the Padma River: 2020 monsoon floods

The 2020 Monsoon floods submerged two-thirds of Bangladesh, profoundly affecting the stable char areas along the Padma River. This study addresses the under-explored link between Monsoonal flood hydrology and river morphological changes, introducing a novel approach that integrates one-dimensional steady flow hydraulic modeling, dual-sensor satellite imagery analysis (Sentinel-1 SAR and Sentinel-2 optical), and multiple machine learning techniques to assess flood impacts on bank erosion in the most affected reaches. Multiple linear regression (MLR), random forest (RF), artificial neural networks (ANN), and support vector machines (SVM) along with other statistical analyses, were employed to elucidate relationships between hydraulic variables and bank erosion. Results indicated a gradual decrease in river discharge-related variables from July to October, with peak erosion in July, primarily along the right banks and concave areas. In analyzing the relationships between hydraulic variables and bank erosion, the ANN model outperformed others, identifying flow area, stream power, and shear stress as the most influential predictors through importance analysis. This integrated approach offers a transferable framework for analyzing flood-induced bank erosion, enhancing riverbank erosion understanding crucial for flood risk management strategies in Bangladesh and similar river systems worldwide.

Comsol Multiphysics modeling of an electrochemical biosensor using carbon nanotubes for detecting urinary estrogen receptor

A class of steroid hormones known as estrogens is essential for the health of the heart, bones, and reproductive system. Changes in estrogen levels have been connected to several health problems, such as endocrine disorders, metabolic syndromes, and cancer. In pharmaceutical applications, environmental monitoring, and medical diagnostics, biosensors that measure estrogen levels are essential. This study models estrogen detection biosensors based on urine liquid, horseradish peroxidase biorecognition, and carbon nanotubes (CNT) using Comsol Multiphysics. This study demonstrates that most interactions happen at the upper boundary of the concave pillars put inside the box. Besides, it shows that the velocity has the highest value between the concave pillars inside the box. The results demonstrate that the number of interactions (absorption and adsorption) rises with increasing the concave pillars' area, affecting the biosensor output.

Rational utilization of the size and electronic effect of inhibitors enabling high polishing rate with minimum corrosion in copper chemical mechanical polishing

Chemical mechanical polishing (CMP) relies on corrosion to remove excess materials, while also on corrosion inhibitors to ensure post-polished surface quality. The robust adsorption of inhibitors onto metal surfaces typically improves inhibition effectiveness but significantly reduces the polishing rate. In this study, we propose and validate a novel strategy that focuses on the utilization of large-sized physisorption-type inhibitors to address this inherent conflict. By incorporating disproportionated rosin (DR) as the inhibitor, the developed slurry facilely obtained a balance between polishing efficiency and quality for copper CMP. The inhibition mechanism of DR was elucidated through electrochemical characterization, adsorption isotherms, and reactive forcefield molecular dynamics (ReaxFF MD) simulations. The weak physisorption of the inhibitors facilitated their easy removal, resulting in minimal impact on the polishing rate. Additionally, the large-size structure of DR effectively hindered corrosive substances from reaching concave areas not under external force, thereby demonstrating superior inhibition efficacy. The adsorption mode of DR on copper was simultaneously determined through adsorption isotherms and ReaxFF MD simulations, marking the first instance of linking classic adsorption theory with MD simulations. The advantage of the ReaxFF MD simulations over classic MD simulations and density-functional-theory calculations for the metal-inhibitor adsorption systems was also discussed and demonstrated.

Three-dimensional surface reconstruction from reflectance direction fields with orthogonal multicolor filters

A three-dimensional (3D) freeform surface reconstruction method is proposed, specifically designed to handle complex surfaces, even those with steep inclinations. This method utilizes a one-shot color mapping imaging system to obtain reflectance direction fields using a stripe multicolor filter positioned in two orthogonal orientations. This imaging system can capture reflectance directions that are identifiable by corresponding colors. The multicolor filter consists of multiple stripe regions, each with a different transmission spectrum. Theoretically, an equation that describes the relationship between reflectance direction fields and the reflective 3D surface can be derived based on geometrical optics. By solving this equation using a deep neural network (DNN) as a gradient descent method without any training data, the 3D surface can be accurately reconstructed, even for surfaces with steep inclinations. The effectiveness of this method is validated through numerical demonstrations on several 3D surfaces, including complex ones with concave and convex areas, as well as steep inclinations.

Management of Atypical M-Shaped Zygomatic Arch Fractures.

M-shaped zygomatic arch fractures can usually be treated effectively through closed reduction. It consists of 2 fracture segments: the anterior zygomatic segment and the posterior temporal bone segment. In clinical practice, atypical M-shaped fractures are often encountered, in which the anterior and posterior fracture segments are discontinuous and separated. Closed reduction usually cannot achieve the desired anatomic reduction effect for this type of fracture. The preoperative design showed that the anatomic reduction of the posterior zygomatic arch fracture segment was hindered due to bone spurs in the most concave area of the anterior zygomatic bone fracture segment. Open reduction and fixation were performed to achieve anatomic reduction and restore facial symmetry. The fracture sites were exposed through a hemicoronal incision. After the bone spurs are removed, the posterior bone segment can be anatomically reduced. Absorbable plates were used for fixation. The patient's facial appearance was restored after the surgery. The postoperative computed tomography scan showed a good alignment of the fracture. The authors believe that for patients with high requirements for facial symmetry, the presence of atypical M-shaped fractures can indicate open reduction and fixation.

Preferential water vapor condensation on a corrugated surface: A molecular dynamics study

In this study, we investigate the nucleation and subsequent growth of water clusters on corrugated surfaces using molecular dynamics simulations, with a specific focus on scenarios where the nanostructure sizes are comparable to the critical nucleus size. The primary objective is to reveal the coupled effects of different surface morphologies, i.e., plane, convex, and concave, on water vapor condensation. Regardless of the nanostructures, the condensation process can be divided into two stages, the nucleation stage and the growth stage. It is shown that in the nucleation stage, the concave areas are more conducive to nucleation compared to plane areas, aligning with classical nucleation theory. The total number of condensed molecules is generally proportion to the nucleation ability, while the average size of condensation clusters is affected by the surface nanostructures, with the combination of concave and plane surfaces exhibiting the strongest capability for both water vapor nucleation and cluster growth. Compared to the plane regions, the convex regions not only inhibit nucleation but also block collision and coalescence between clusters. Additionally, increasing the characteristic width of concave and convex structures leads to condensation behaviors approaching those on the plane surface. This indicates that the regulation of the condensation process is feasible by nanostructures within prescribed structural size limits.

EFFECT OF THE CURVATURE PARAMETER AND İTS CLASSİFİCATİON ON LANDSLİDES

The first question that generally comes to mind about the curvature parameter is whether this parameter is suitable for the study area. This question uses every parameter to be asked, but some effects that are implemented incorrectly, such as curvilinearity, raise question marks. As a result of technical errors and conceptual confusion regarding the parameter, the landslide area defined as concave by one researcher may be defined as convex by another researcher. For this reason, some researchers state that they contradict the literature and produce results contrary to their expectations. Due to such negativities, there is no consensus in the literature regarding curvilinearity parameters. This determination was used for 64 areas selected for curvature parameters in three different classes and the prices of their changes in total. By examining the maximum and minimum distributions in the landslide area, it was investigated what kind of change it caused in concave, convex and flat areas depending on the terrain. As a result of the analysis, it was revealed that class intervals that could not be determined correctly resulted in cracks in the landslide capacity proportional distributions. Thus, the study achieves the main goal that will facilitate the use of the curvature parameter.

What is moving where? Infants' visual attention to dynamic objects may assist with processing of spatial relations.

A central question in infant spatial cognition concerns how infants form abstract categories of spatial relations such as support (on) and containment (in). Prior work suggests two different possibilities regarding the role of attention to objects in infants' formation of abstract categories of spatial relations: Attention to objects may compete with (and thus hamper) attention to the spatial relations between them, or assist with encoding of the spatial relation information. Using eye-tracking, we examined how infants' visual attention to objects related to their successful formation of an abstract category of support relations (i.e., an object on another). Thirty-eight 8-month-old infants' eye movements were recorded during a support categorization task, where infants were habituated to four dynamic events depicting support relations (e.g., resting a block on a box) and then presented with test events that depicted either a support or containment relation with objects that they had seen or not seen in the habituation phase. Based on their looking time to the familiar versus novel spatial relation in the test, infants were classified into two groups: categorizers, who formed an abstract category of a support relation, and non-categorizers, who did not do so. During their initial phase of learning (i.e., the first habituation trial), categorizers paid greater attention to the object moved by a hand (i.e., the dynamic object) in comparison to non-categorizers, whereas their attention to the static object or their gaze shifts between the two objects did not differ. In addition, when presented with novel objects in a novel spatial relation after habituation, only categorizers displayed asymmetric attention between the objects, attending to the dynamic object more than the static object. Gaze shifts and attention to the concave area (i.e., hole) of the container did not differ between categorizers and non-categorizers. These findings suggest that infants' focused attention to an object in motion may play a key role in young infants' spatial category learning, and support the idea that attention to objects can assist with encoding of the spatial relational information.

Flow enhanced corrosion of tee in gas transmission pipeline

A tee failed due to flow enhanced corrosion at an oil field was investigated and analyzed by macroscopic analysis, nondestructive tests, material tests (including chemical composition, metallurgical analysis) and microstructure analysis (including microtopography, SEM, EDS and XRD) in this paper. It was concluded that the chemical composition and metallurgical properties of the tee accord with related standards, and the anti-corrosion coating on the inner wall peeled off is considered as one of the main failure factors of tee. The corrosion failure mechanism analysis results shows that the change of flow pattern caused the sudden change of the inner diameter between weld reinforcement and nickel based coating results in water gathering and flow enhanced corrosion at the concave area. Also, galvanic corrosion occurs at the concave area formed by weld reinforcement and nickel based coating between the carbon steel tee and nickel based coating due to high electrode potential difference. The galvanic corrosion further accelerated the corrosion process. Under the combined action of erosion, galvanic corrosion and flow enhanced corrosion, perforation leakage finally occurs.

Stress Distribution of Endodontically Treated Tooth MOD Cavity Restored with Ribbon Fiber-Reinforced Composite (Wallpapering Technique) Using Finite Element Method.

This research aimed to describe the stress distribution of an endodontically treated tooth with a mesio-occluso-distal (MOD) cavity restored with direct composite reinforced with polyethylene and e-glass ribbon fiber. This research was a descriptive study using the finite element method. A 3D model of the mandibular first molar solid after endodontic treatment with class II MOD preparation was prepared using Solidworks software. Finite element simulation was carried out using Abaqus software. In the first simulation, 180 N force was applied (vertically 90° perpendicular to the occlusal surface) at four points of loading: the tip of the mesiobuccal and distobuccal cusp, central fossa, and distal marginal ridge. For the second simulation, a 100 N force was applied at a 45° lateral angle to the occlusal surface at two loading points: the lingual slope of the mesiobuccal and distobuccal cusp. This study showed that the stress concentration was located in the occlusal pit and fissure, CEJ distal area, bifurcation in dentin, and the 1/3 cervical area of root dentin. The stress value generated after vertical and lateral force did not exceed the tooth and restoration's compressive and tensile strength value. The failure occurred at the interface of enamel and composite near the loading point area due to vertical load, both on polyethylene and e-glass fiber ribbon-reinforced composite restoration. Stress distribution of an endodontically treated tooth with a MOD cavity restored with ribbon fiber-reinforced composite using the finite element method showed that the highest stress concentration occurred on the surface close to the loading point, in narrow, concave, and sharp areas, and more apically for endodontically treated teeth. Neither the tooth nor restoration failed after vertical and horizontal loads. The interface between enamel and composite on the occlusal surface failed.

Microstructure evolution of melt-extracted copper alloy wires

Copper alloy wires are regarded as essential for bonding in semiconductor packaging. However, the existing single-crystal copper wires are susceptible to oxidize, resulting in connection failure. And the current production process of multi-pass cold-drawing is complicated. In this study, nickel-aluminum-bronze (NAB) alloy wires by the melt-extracted method were investigated to avoid the problems mentioned above. The results showed that the microstructure of the copper alloy wire differs depending on the region. The nano-Ni3Al phase precipitates on the lath martensitic β' phase in the concave area, while the interior of the copper alloy wires contains a large number of reflection-twin of the β' phase. As the melt-extracted process continues, the cooling speed increases until the formation of the stable lamellar αw + β' structure. These results will shed new light on the formation mechanism of copper alloy bonding wires.

Investigating the factors influencing the bridging of dry non-crimp fabric on a concave L-shaped mold in an automated draping process

Dry technical textiles tend to bridge when draping in concave areas or complex geometries such as internal corners. The extent of bridging is based on the spring-back of the textile. In this study, the value for the spring-back for dry technical textiles is defined and a method to quantify the spring-back value is proposed. An automated continuous draping process is presented based on manual lay-up and draping process of dry non-crimp fabrics (NCF) which is used in the production of rotor blade shells for wind turbine blades. This process provides the basis for the study of spring-back behaviors. Within this process, a triaxial NCF sample is manually laid-up on an L-shaped mold and then automatically draped onto the edge using a draping tool. A laser scanner records the draping result and bridging of the NCF sample. Test series show the influence of the process parameters such as drape speed and drape force on the spring-back behavior. For the draping process under consideration, quadratic dependencies of these factors on the spring-back could be determined.

Proportion of charcoal carbon in the forest floor carbon pool in relation to fire history in a boreal forest landscape

AbstractFire in the boreal forests emits substantial amounts of organically bound carbon (C) to the atmosphere and converts a fraction of the burnt organic matter into charcoal, which in turn is highly refractory and functions as a long‐term stable C pool. It is well established that the boreal forest charcoal pool is sufficiently large to play a significant role in the global C cycle. However, there is a need for spatially representative estimates of how large proportions of the forest floor C pool are made up of charcoal across different plant communities in the boreal forest ecosystem. Thus, we have quantified the amounts of C separately in charcoal and the organic layers of the forest floor across fine spatial scales in a boreal forest landscape with a well‐documented fire history. We found that the proportion of charcoal C made up an average of 1.2% of the total forest floor C, and the charcoal proportions showed a high small‐scale spatial variability and were concentrated in the organic–mineral soil interface. Proportions of charcoal C decreased with increasing time since last fire. Deeper soils, denser soils, and local concave areas had the highest proportions of charcoal C, whereas historical fire frequencies and current differences in vegetation did not relate to the proportions of charcoal C.

Evaluation and Error Source Analysis of Convection‐Permitting Forecasts for Localized Nocturnal Rainfall Over a Complex Mountainous Region in Pearl River Delta, South China

AbstractThe concave mountainous area of Pearl River Delta (PRD) is a summer rainfall hotspot of South China due to the presence of warm‐moist monsoon flow and complex orography. This study evaluated the performance of a convection‐permitting Weather Research and Forecasting (WRF) model in forecasting nocturnal rainfall in this area, focusing on days with low level southwesterly winds during the summers of 2013–2015. Results showed that the nocturnal rainfall exhibited two centers, one located along the large‐scale northern mountains and the other along the small‐scale Huadu Hill. WRF demonstrated superior performance in predicting rainfall over the northern mountainous region. In contrast, WRF significantly underestimated nocturnal rainfall both near local Huadu Hill and in the foothill area of northern mountains, which were strongly influenced by local forcings. Using high‐resolution analyses from Variational Doppler Radar Analysis System (VDRAS) and Automatic Weather Stations observations, we firstly identified the sources of forecast errors in triggering a typical localized nocturnal convection. Results revealed that WRF severely underestimated thermal contrast between the Guangdong‐Hong Kong‐Macao Greater Bay Area urban agglomeration and the concave mountains, leading to the absence of the northeastern/northern inflows toward the cities. Consequently, low level convergence and updrafts near the convection initiation position were too weak to lift air parcels above the severely overestimated level of free convection, thereby failing to trigger the convection. VDRAS‐based sensitivity experiments, with a specific focus on assimilating surface temperature, validated the crucial role of urban‐mountain thermal contrast on local winds that triggered the nocturnal convection.

Improving the Design of Combine Harvesters by Harmonizing Their Basic Technical Parameters

Introduction. The article presents the results of statistical analysis of basic technical parameters of modern combine harvesters, comprising a sample of 150 models. A new complex criterion for assessing the technical level of combine harvesters called the harmonization coefficient is proposed, which makes it possible to evaluate the perfection degree of combine harvester design and identify the ways to improve them. Aim of the Article. The aim of the study is to propose a methodology for calculating the harmonization coefficient of each combine harvester and to identify the way for its improvement, based on the degree of compliance with global trends. The article continues to develop the idea of harmonization of combine harvester parameters outlined in the previous publications on this topic. Materials and Methods. There was applied statistical analysis identifying homogeneous statistical samples by harvester classes from 4 to 12 kg/sec. Results. On the example of a sample of 16 different combine harvester models, the harmonization coefficients of combine harvester design were calculated. The applied statistical equations for calculating combine harvester parameters reflect global trends in the development of combine harvester design and were called theoretical parameters, then they were compared with the actual parameters of combine harvesters. The difference between the theoretical and actual parameters affected the identifying of the ways of improvement. There were identified the combine harvester brands with high harmonization coefficient and a number of combine harvesters requiring modernization. Discussion and Conclusion. A technique for digital assessment of the technical level of combine harvesters is proposed. It is based on three design criteria: parametric index, regression dependencies between combine parameters reflecting global trends in the combine harvester design, and the harmonization coefficient of the combine harvester design in terms of threshing and separating device parameters. There was identified a group of combine harvesters with a very high harmonization coefficient 0.93‒0.94. We mean first of all German harvesters of Claas company (Medion 340, Dominator 150, Lexion 580), Russian harvester of Rostselmash company (TORUM 740) and American Massey Ferguson (MF 7278). There is a large group of combine harvesters, which have a harmonization coefficient of their design in terms of parameters below 0.9, therefore, they may be improved in accordance with global trends, for example, the 5270 C-AL combine harvester of the German company Fendt needs the increase in engine power from 180 HP to 252 HP, reducing the concave area from 1.3 to 0.81 m2, increasing the area of the straw separator from 5.7 to 7.2 m2 and reducing the area of the cleaning sieves from 6.0 to 5.4 m2. At the same time, the combine harvester throughput efficiency will remain at the level of 9.1 kg/s. Based on the proposed methodology, there are given recommendations for improving a number of the most famous combine harvesters of domestic and foreign production, taking into account global trends in their development.

Role of surface morphology in bed particle layer formation on quartz bed particles in fluidized bed combustion of woody biomass

The influence of quartz bed particle surface morphology on the bed particle layer and crack layer formation process in fluidized bed combustion of woody biomass was investigated in this work. Bed material samples were collected at different sampling times from the startup with a fresh bed in industrial scale bubbling fluidized bed (BFB) and circulating fluidized bed (CFB) boilers, both utilizing woody biomass. X-ray microtomography (XMT) and scanning electron microscopy coupled with energy dispersive spectroscopy (SEM/EDS) were employed to characterize bed particle layers and crack layers in the samples. Results showed that there is a noticeable difference between the bed layer characteristics over the so-called “concave” and “convex”-shaped morphologies on the bed particle surface with respect to layer formation. The concave areas are mainly covered with a thin inner layer, whilst the convex display a comparably thick inner layer and an outer layer. In addition, 3D images of the particles revealed that the crack layers mainly originate from concave areas where the particle is less protected by an outer bed particle layer in conjunction with cracks in the inner layer.

Coverage Path Planning Method for Agricultural Spraying UAV in Arbitrary Polygon Area

In the coverage path planning (CPP) problem of an agricultural spraying UAV, a margin reduction algorithm was designed first to address special situations such as ditches and channels within the operational terrain. Regarding the particularity of a concave polygon area, an algorithm based on topology mapping was developed to judge the concave points of the concave polygon area, and the path with special concave points was scheduled. For the evaluation of the pesticide spraying mission, the flight distance and extra coverage ratio were the most appropriate optimization objectives. Therefore, this paper selected these two indicators to form a fitness function, then found the optimal operating heading angle of the mission after iterative optimization. Finally, the CPP for an agricultural spraying UAV in an arbitrary polygon area under the optimal heading angle was realized. The simulation and flight test results showed that the CPP method could significantly shorten the flight distance and reduce additional coverage, then avoid energy consumption and pesticide waste. In addition, the engineering practicability of the method was verified in this paper. This method can be popularized and widely used for an agricultural spraying UAV, which has great engineering application value.

An assistant algorithm model for a mobile robot to pass through a concave obstacle area

When a mobile robot passes through a concave obstacle area, the limitations of the traditional control algorithm add a significant challenge to the mobile robot to move through the concave obstacle area efficiently. Improving the conventional path planning algorithm is a common choice to solve this problem. However, because various path planning algorithms adapt to the fixed scene and the algorithm steps are complex, it is difficult to popularize these algorithms. In addition, conventional path planning algorithms usually encounter difficulties when passing through recessed obstacle areas or cause robot deadlock. An auxiliary algorithm strategy is proposed to help mobile robots avoid concave obstacles quickly. The algorithm strategy plays an auxiliary role by incorporating the judgment of the starting position of the mobile robot, the building of a virtual wall to shield the concave obstacle area, and the judgment of the moving direction of the mobile robot. The advantage of this algorithm strategy is that it does not change the operation mechanism of traditional path-planning algorithms and is highly adaptable. The results of the comparison of simulation experiments with the APF (Artificial Potential Field), the ACO (Ant Colony Optimization), the RRT (Rapidly-Exploring Random Trees), the A-star algorithm, and the Dijkstra algorithm show the inclusion of the auxiliary algorithm strategy resulted in a significant increase in the efficiency of the mobile robot through the depressed obstacle zone.Article Highlights●This auxiliary algorithm strategy can avoid the self-locking caused by the mobile robot falling into the concave obstacle area.●This auxiliary algorithm strategy does not change the mechanism of the traditional path planning algorithm, and it is simple and easy to be used.●This auxiliary algorithm has wide adaptability (it can assist the mainstream path planning algorithm and adapt to various scenarios).