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As in other countries, In Brazil, new genetic materials of Eucalyptus spp. and their hybrids are multiplied through cloning. These materials, currently in experimental trials, must undergo several stages to select the best ones for pulp and paper production. Therefore, new studies on wood quality are essential. Therefore, this study aimed to group 11 clones of Eucalyptus spp. wood, from a clonal plantation in the municipality of Palmital, São Paulo State, for the production of paper and cellulose. For this purpose, four trees of each clone of 4-year-old Eucalyptus spp. were collected. From each tree, a log of 1 m in length was taken from the base of the tree, for the study of the characterization of the basic density and cellular dimensions of the wood. The results showed that there were significant differences between clones for basic density, fiber length, vessel element length and fiber wall thickness. The Runkel ratio, wall fraction and stiffness coefficient did not show significant differences between the different genotypes. From the results obtained, we can conclude that clones can be differentiated only by basic density, fiber length, vessel element length and fiber wall thickness. The Runkel index, flexibility coefficient and wall fraction of Eucalyptus spp. were more efficient to group the clones into two groups.

Stretchable displays based on conventional materials exhibit a trade‐off relationship between the pixel density and the stretchability. In this paper, we have demonstrated overcoming the technological limitations of stretchable displays through the optimization of serpentine‐shaped bridge design and the application of stretchable metal electrodes. The application of stretchable electrodes has increased stretchability by over 30% without compromising pixel density. [ABSTRACT FROM AUTHOR]

Density is an important indicator for evaluating diesel fuel quality that directly affects the injection timing and injection rule of the engine, and also has a significant impact on the spray broken particle size, the spray penetration distance, the spray cone angle, and so forth, which in turn affects the combustion process and pollutant emission of the compression-ignition engine. Therefore, it is important to accurately predict the diesel fuel mixture density in industrial and compression-ignition engines. However, the mathematical models for predicting the density of diesel fuel mixture with changed temperature are relatively lacking and less accurate, especially for ternary diesel fuel mixtures with different physicochemical properties. This paper proposes a mathematical model including binary and ternary diesel mixtures under changed fuel volume fraction and temperature, and published data were used for verification. The data verification results show that: for the density prediction of binary diesel fuel mixtures at constant temperature, the average relative deviation (ARD) is 0.0245%, the RMS error (RMSE) is 0.000344, and the correlation coefficient (R) is 0.9993. For the density prediction of binary diesel fuel mixtures at changed temperature, the ARD is 0.0609%, the RMSE is 0.000695, and R is 0.9980. For the density prediction of ternary diesel fuel mixtures at constant temperature, the ARD is lower than 0.0571%, the RMSE is lower than 0.000610, and R is higher than 0.9861. For the density prediction of ternary diesel fuel mixtures at changed temperature, the ARD is 0.0484%, the RMSE is 0.000513, and R is 0.9996. The diesel mixed fuel density prediction model proposed in this paper has good accuracy and calculation convenience, and provides important reference value for measuring or designing the density of diesel mixed fuel in the field of compression-ignition engines. [ABSTRACT FROM AUTHOR]

The experimental measurement of density and enthalpy of mixture for two binary liquid mixtures of n-tridecane or n-tetradecane with decalin was reported in this paper. The measurements were conducted at a temperature range of 293.15–323.15 K and at 303.15 K using calorimeter C80. The mixtures were analyzed at various proportions, including the entire composition range and dilute solutions. The excess molar volume (VE) and excess molar enthalpy (HE) of mixtures were calculated and fitted using the Redlich–Kister equation. The paper observed the expansion phenomenon for the VE at all temperatures, including over the entire composition range and dilute solutions. Additionally, the HE exhibited endothermic behavior at the studied temperature range and composition range. The Prigogine–Flory–Patterson (PFP) theory was utilized to predict both thermodynamic properties, namely the VE and HE. The results obtained using the PFP theory were compared with those obtained using the Treszczanowicz and Benson association (TB) model for VE and with the NRTL, Wilson, and Flory models for HE. The PFP model, which employed a single-fitted parameter to describe VE, demonstrated satisfactory performance in predicting VE. Conversely, the Treszczanowicz and Benson association (TB) model yielded relatively poor results in fitting VE. However, the NRTL, Wilson, PFP, and Flory models exhibited good performance in predicting HE. [ABSTRACT FROM AUTHOR]

Egocentric networks represent a popular research design for network research. However, to what extent and under what conditions egocentric network centrality can serve as reasonable substitutes for their sociocentric counterparts are important questions to study. The answers to these questions are uncertain simply because of the large variety of networks. Hence, this paper aims to provide exploratory answers to these questions by analyzing both empirical and simulated data. Through analyses of various empirical networks (including some classic albeit small ones), this paper shows that egocentric betweenness approximates sociocentric betweenness quite well (the correlation is high across almost all the networks being examined) while egocentric closeness approximates sociocentric closeness only reasonably well (the correlation is a bit lower on average with a larger variance across networks). Simulations also confirm this finding. Analyses further show that egocentric approximations of betweenness and closeness seem to work well in different types of networks (as featured by network size, density, centralization, reciprocity, transitivity, and geodistance). Lastly, the paper briefly presents three ideas to help improve egocentric approximations of centrality measures. [ABSTRACT FROM AUTHOR]

This paper focuses on the implementation of a neural network accelerator optimized for speed and energy efficiency, for use in embedded machine learning. Specifically, we explore power reduction at the hardware level through systolic array and low-precision data systems, including quantized approaches. We present a comprehensive analysis comparing a full precision (FP16) accelerator with a quantized (INT16) version on an FPGA. We upgraded the FP16 modules to handle INT16 values, employing data shifts to enhance value density while maintaining accuracy. Through single convolution experiments, we assess the energy consumption and error minimization. The paper's structure includes a detailed description of the FP16 accelerator, the transition to quantization, mathematical and implementation insights, instrumentation for power measurement, and a comparative analysis of power consumption and convolution error. Our results attempt to identify a pattern in 16-bit quantization to achieve significant power savings with minimal loss of accuracy. [ABSTRACT FROM AUTHOR]

In this paper, given a prescribed measure on \mathbb {S}^1 whose density is bounded and positive, we establish a uniform diameter estimate for solutions to the planar L_p dual Minkowski problem when 0

This paper focuses on the theoretical study of the burning rate of D-T fuel in Z-pinch devices with magneto-inertial confinement. The investigated nuclear fusion process involved fast laser ignition of a mixed D-T fuel contained in a capsule at a temperature of 10 keV, influenced by a strong electromagnetic field. The D-T, D-D, D-3He, 3He-3He, and T-T fusion reactions were employed in the calculations. Based on modern experimental fit data of nuclear fusion reaction rates, the particle and energy balance equations, along with their numerical solutions, were considered, utilizing the ion densities of charged particles such as protons, deuterium, tritium, 3He, and 4He ions. The plasma was in a hot, ultra-dense state, under the quasi-neutrality condition, with initial deuterium and tritium densities of 5 × 10 23 cm−3 and an electron density of 10 × 10 23 cm−3. The ion and electron temperatures were considered equal in this paper. The time dependencies of the ion densities, plasma temperature, energy yield from charged ions and neutrons, fusion power density, and bremsstrahlung radiation loss were investigated. [ABSTRACT FROM AUTHOR]

Deep rock are often in a true triaxial stress state. Studying the impacts of varying unloading speeds on their strain energy (SE) density is highly significant for predicting rock stability. Through true triaxial unloading principal stress experiments and true triaxial stress equilibrium unloading experiments on sandstone, this paper proposes a method to compute the SE density in a true triaxial compressive unloading principal stress test. This method aims to analyze the SE variation in rocks under the action of true triaxial unloading principal stresses. Acoustic emission is used to verify the correctness of the SE density calculation method in this paper. This study found that: (1) Unloading in one principal stress direction causes the SE density to rise in the other principal stress directions. This rise in SE, depending on its reversibility, can be categorized into elastic and dissipated SE. (2)When unloading principal stresses, the released elastic SE density in the unloading direction is influence by the stress path and rate. (3) The higher the unloading speed will leads to greater increases in the input SE density, elastic SE density, and dissipative SE density in the other principal stress directions. (4) The dissipated SE generated under true triaxial compression by unloading the principal stress is positively correlated with the damage to the rock; with an increase in unloading rate, there is a corresponding increase in the formation of cracks after unloading. (5) Utilizing the stress balance unloading test, we propose a calculation method for SE density in true triaxial unloading principal stress tests. [ABSTRACT FROM AUTHOR]

In the modern era, the demand for lightweight footbridges has grown significantly. However, this trend introduces new challenges related to the dynamic behaviour of such structures, especially under pedestrian-induced loading. This paper investigates the dynamic response of footbridge decks, focusing on the effects of vibration, pedestrian loading, and design considerations. Through a detailed analysis of a simply supported footbridge, we evaluate natural frequencies, critical ranges, and acceleration responses under varying pedestrian densities. The results emphasize the need for careful consideration of dynamic effects in the design phase to ensure pedestrian comfort and structural safety. [ABSTRACT FROM AUTHOR]

Tourism, as a form of spending free time, has undergone numerous transformations in the last period of time, this is due both to globalization that contributed to the internationalization of tourist experiences, but also to recent events (such as the Covid-19 pandemic, economic crises, etc), but also changing the perception of tourism consumers regarding how they can spend their free time. Traditional or well-known destinations have started to face overcrowding, which is starting to be felt negatively by both residents and visitors who are starting to change their consumption habits regarding the locations they choose as tourist destinations. On the other hand, the challenges of the modern world regarding the effects of global warming, the sharp increase in the population, the depletion of planetary resources, but also the much greater concerns of the current generations regarding these aspects, make the choices we make regarding the choice leisure destinations to change and become more responsible. In this context, creative tourism as an increasingly sought-after option, among a growing category of consumers. In this paper, we set out to analyze the perception that tourism consumers in Romania have regarding this form of tourism. The research assumed, on the one hand, a bibliographic analysis regarding the term creative tourism and how this notion has evolved from the moment of its definition as a form of tourism in the 2000s until now, as well as from a study of case based on the application of a questionnaire to measure the perception of consumers regarding this form of tourism, but especially on the awareness of its existence. The questionnaire had 16 questions answered by 124 respondents. The data were centralized and interpreted with the help of the Excel program, the results highlighting the fact that although some of the respondents practice creative tourism, it is quite little known as a concept. The answers given by the study participants highlighted the fact that they are interested in practicing activities integrated into creative tourism, considering that there are many advantages both regarding the experiences they create, with the interactions they establish with the locals or with the other participants. At the same time, the impact that creative tourism practices have at the local level (both economic and social) is recognized. We consider that these results are useful not only at the micro level, but also at the macro level, under the conditions that the development strategies of the field of hospitality will be thought in such a way as to promote, integrate and develop this form of contemporary tourism. [ABSTRACT FROM AUTHOR]

In this paper, we propose a Grid-based Non-uniform Probability Density Sampling Probabilistic Roadmap algorithm (GN-PRM) in response to the challenges of difficult sampling in narrow passages and low-probability map generation in traditional Probabilistic Roadmap algorithms (PRM). The improved algorithm incorporates grid-based processing for map segmentation, employing non-uniform probability density sampling based on the different attributes of each block to enhance sampling probability in narrow passages. Additionally, considering the computational cost and frequent ineffective searches in traditional PRM algorithms during pathfinding, this paper optimizes the time required for query route planning by altering connection strategies to improve the algorithm's runtime. Finally, the simulation results indicate that, with a reduction of over 50% in undirected line segments and a reduction of over 85% in runtime, the GN-PRM algorithm achieves a 100% success rate in complex planning scenarios with a sampling point value of K = 500. In comparison, the traditional PRM algorithm has a success rate of no more than 10%, with a sampling point value of K = 500. [ABSTRACT FROM AUTHOR]

Due to the presence of non-line-of-sight (NLOS) obstacles, the localization accuracy in ultra-wideband (UWB) wireless indoor localization systems is typically substantially lower. To minimize the influence of these environmental factors and improve the accuracy of indoor wireless positioning, this paper proposes a density clustering with noise combined with particle swarm optimization (DCNPSO) to improve UWB positioning. Which exploits the advantages of the density-based spatial clustering algorithm with noise (DBSCAN) and particle swarm optimization (PSO) algorithm. The experimental results show that the DCNPSO algorithm achieves 45.25% and 36.14% higher average positioning accuracy than the DBSCAN and PSO algorithms, respectively. The positioning error of this algorithm remains stable within 3 cm in static positioning and can achieve high accuracy in NLOS environments. [ABSTRACT FROM AUTHOR]

A belowground bud bank is a collection of asexual propagules produced by the underground storage organs of geophytes. Renewal through belowground bud banks is the main reproductive strategy of geophytes. The belowground bud bank density reflects the potential renewal capacity of geophyte communities. However, the effects of different perturbation regimes and habitats on the belowground bud bank density of geophytes are not comprehensively understood. Moreover, whether different types of belowground bud banks respond differently to perturbations is still unclear. For this meta-analysis, relevant papers on the effects of environmental perturbations on the belowground bud bank density of geophytes were systematically collected. The cumulative effect size of different perturbation regimes and habitats on belowground bud banks among different bud types was analyzed. Overall, the effect of environmental perturbations on belowground bud bank density was small, which may result from opposite or fluctuating responses of bud banks to different perturbations. Drought negatively affected bud bank density. Environmental perturbations decreased rhizome bud density but increased tiller bud density. In wetlands, perturbations decreased belowground bud bank density. However, no significant effect was found for other habitat types. In general, belowground bud banks of geophytes are highly resistant and resilient. Changes in belowground bud bank density depend on the type of perturbations, the habitats in which plants are distributed and the type of bud banks. [ABSTRACT FROM AUTHOR]

In this paper, we are interested in studying Bishop–Phelps–Bollobás type properties related to the denseness of the operators which attain their numerical radius. We prove that every Banach space with a micro-transitive norm and the second numerical index strictly positive satisfies the Bishop–Phelps–Bollobás point property, and we see that the one-dimensional space is the only one with both the numerical index 1 and the Bishop–Phelps–Bollobás point property. We also consider two weaker properties L $ {}_{p,p} $ p , p -nu and L $ {}_{o,o} $ o , o -nu, the local versions of Bishop–Phelps–Bollobás point and operator properties respectively, where the η which appears in their definition does not depend just on $ \varepsilon > 0 $ ε > 0 but also on a state $ (x, x^*) $ (x , x ∗) or on a numerical radius one operator T. We address the relation between the L $ {}_{p,p} $ p , p -nu and the strong subdifferentiability of the norm of the space X. We show that finite dimensional spaces and $ c_0 $ c 0 are examples of Banach spaces satisfying the L $ {}_{p,p} $ p , p -nu, and we exhibit an example of a Banach space with a strongly subdifferentiable norm failing it. We finish the paper by showing that finite dimensional spaces satisfy the L $ {}_{o,o} $ o , o -nu and that, if X has a strictly positive numerical index and has the approximation property, this property is equivalent to finite dimensionality. [ABSTRACT FROM AUTHOR]

Investigation and implementation of Active Willis Metamaterials (AWM) have been done exclusively, in all the available literature, by approaches that do not rely on any solid control theory basis. When coupled with piezoelectric control elements, the available approaches have not included, from the first principles, the exact form of the constitutive relationship of the piezoelectric materials. Furthermore, in all these approaches, stability analysis, robustness, ability to accommodate uncertainty or parameter changes, or consideration of disturbance rejection has not been addressed at all. More importantly, the available formulations have always mixed the flow and effort variables of the AWM, resulting in a form that is totally incompatible for the use in generating, investigating, or even designing any appropriate sensing or control applications of the material. In this paper, the piezoelectric-based AWM is modeled, from the first principles, to develop a constitutive coupling form that enables its use in actuation, sensing, and as an integrated controller that can be analyzed, designed, and optimized using the classical, optimal, and robust control system theories. Lagrange dynamics formulation is used to generate the equations governing the Willis coupling, the piezoelectric coupling, as well as the active robust controller. With this developed controlled-based structure of the AWM, the inherent and powerful capabilities of the AWM that lie in its ability to robustly control the material properties themselves such as the compliance (or stiffness) and specific volume (or density) are demonstrated in great detail via several numerical examples. Controlling these properties enables the AWM to be used in numerous important and imaginative applications such as cloaking, beam shifting, beam focusing, as well as many other applications that are limited only by our imagination. [ABSTRACT FROM AUTHOR]

The variability of Mars exosphere over monthly to solar‐cycle scales at 251 and 412 km altitude is quantified by analysis of 41‐Ls mean densities derived from precise orbit determination of the Mars Reconnaissance Orbiter (MRO) and Mars Odyssey (MO) satellites, respectively. The data encompass 2006–2020 (MRO) and 2002–2020 (MO). At both altitudes, most of the variance is captured by cos(Ls–ϕ), where ϕ ≈ 258°. This term represents the effects of solar heating changes due to the eccentricity of Mars orbit around the Sun, and climatological changes in heating due to lower‐atmosphere dust loading, which does not play a significant role. The remaining variability is connected with the "irregular" variability of solar flux over monthly time scales. For MO, the presence of Helium disrupts a clean correlation with these sources. Plain Language Summary: The force of continuous bombardment of atmospheric particles on a satellite slowly changes its orbit. By tracking the satellite, changes in its orbit can in turn be used to infer atmospheric particle densities. In this paper, we use tracking from NASA's Deep Space Network, an international array of giant antennas, to measure minute orbital changes of the Mars Reconnaissance Orbiter and Mars Odyssey satellite orbits (and thereby atmospheric densities) around Mars during the 2002–2020 time frame. These data are used to study how the outer regions of Mars atmosphere respond to changes in heating due to solar radation absorption by various chemical species, and by dust that is elevated into the atmosphere by strong winds near the surface. The major finding of this paper is that the variability of Mars outer atmosphere is mainly controlled by solar heating changes due to the eccentricity of Mars orbit around the Sun. Key Points: Densities from precise orbit determination of Mars Reconnaissance Orbiter and Mars Odyssey are used to quantify long‐term variability of Mars' exosphereThe annual term is the greatest contributor to total variance, followed by the irregular component of EUV/UV fluxDust‐induced inter‐annual variability is small, but the analysis method does suppress potentially important regional‐scale events [ABSTRACT FROM AUTHOR]

In this paper, the derivation of a concise closed form for the gravitational field of a polyhedron is presented. This formula forms the basis of the algorithm for calculating the gravitational field of an arbitrary shape body with high accuracy. Based on this algorithm, a method for gravity data inversion (creating density models of the Earth's crust) has been developed. The algorithm can accept either regular or irregular polyhedron discretization for density model creation. The models are approximated with dense irregular grids, elements of which are polyhedrons. When performing gravity data inversion, we face three problems: topography with large amplitude, the sphericity of the planet, and a long computation time because of the large amount of data. In our previous works, we have already considered those problems separately but without explaining the details of the computation of the closed-form solution for a polyhedron. In this paper, we present for the first time a performance-effective numerical method for the inversion of gravity data based on topography. The method is based on closed-form expression for the gravity field of a spherical density model of the Earth's crust with the upper topography layer, and provides great accuracy and speed of calculation. There are no restrictions on the model's geometry or gravity data grid. As a case study, a spherical density model of the Earth's crust of the Urals is created. [ABSTRACT FROM AUTHOR]

The relentless pursuit of miniaturization and performance enhancement in electronic devices has led to a fundamental challenge in the field of circuit design and simulation-how to accurately account for the inherent stochastic nature of certain devices. While conventional deterministic models have served as indispensable tools for circuit designers, they fall short when it comes to capturing the subtle yet critical variability exhibited by many electronic components. In this paper, we present an innovative approach that transcends the limitations of traditional modeling techniques by harnessing the power of machine learning, specifically Mixture Density Networks (MDNs), to faithfully represent and simulate the stochastic behavior of electronic devices. We demonstrate our approach to model heater cryotrons, where the model is able to capture the stochastic switching dynamics observed in the experiment. Our model shows 0.82% mean absolute error for switching probability. This paper marks a significant step forward in the quest for accurate and versatile compact models, poised to drive innovation in the realm of electronic circuits. [ABSTRACT FROM AUTHOR]

This paper presents a method for applying forging to high-density wood. A cylindrical container was formed using a closed die, and the appropriate conditions for temperature and punch length were evaluated. Ulin, which is a high-density wood, and Japanese cedar, which is a low-density wood and widely used in Japan, were used as test materials. The pressing directions were longitudinal and radial based on wood fiber orientation, and the shape and density of the resulting containers were evaluated. In the case of ulin, cracks decreased by increasing the temperature, while temperature had little effect on Japanese cedar. Containers without cracks were successfully formed by using a punch of appropriate length. The density of the containers was uniform in the punch length l = 20 and 40 mm in the L-directional pressing and l = 20 mm in the R-directional pressing when using ulin, with an average density of 1.34 g/cm3. This result indicates the forging ability of ulin is high compared to that of commonly used low-density woods. In summary, this paper investigated the appropriate parameters for forging with ulin. As a result, products of more uniform density than products made by cutting were obtained. [ABSTRACT FROM AUTHOR]

In the process of societal development, forest land categories often conflict with other land use types, leading to impacts on the ecological environment. Therefore, research on changes in forest land categories has increasingly become a globally focused topic. To anticipate potential forest ecological security issues under urbanization trends, studies on regional land use simulation become more important. This paper, based on land use data from the Ganjiang River basin, analyzes the distribution characteristics and changing trends of land use types from 2000 to 2020. Using the CA-Markov model, it predicts the land use pattern of the basin in 2040 and analyzes the transfer characteristics of forest land categories. The conclusions indicate that, between 2000 and 2020, the most significant trend in land use evolution was the transfer between various subcategories of forest land, especially frequent in the high-altitude mountainous areas in the southern and western parts of the basin. The land use pattern prediction model constructed in this paper has a kappa index of 0.92, indicating high accuracy and reliability of the predictions. In 2040, the most significant land evolution phenomenon would be from forest land to arable land to construction land, particularly pronounced around large cities. Over the next 20 years, the focus of land use evolution may shift from the southern part of the basin to the central and northern parts, with urban expansion possibly becoming the main driving force of land use changes during this period. Forest land restoration work is an effective method to compensate for the loss of forest land area in the Ganjiang River basin, with key areas for such work including Longnan, Yudu, Xingguo, Ningdu, Lianhua, and Yongxin counties. [ABSTRACT FROM AUTHOR]

This paper aims to identify the spatial structure of Manado municipal, capital of North Sulawesi Province in Indonesia, through its density profile as indicator, which is the trend of density level according to the spatial units distance to the city center. This paper also tries to elaborate on the potential problems in the city as well as the urban planning policy which are associated with the spatial structure identified. The data used are the maps of administrative and built-up area and the distribution of population and service center by spatial units in Manado. The parameters of density profile examined are the administrative and built up density and the accessibility distance to the city center from the service center of the spatial units. By interpreting the existing density profile based on some relevant theoretical premises, the spatial structure type and its associative problems and policy can be identified. The result shows that the spatial structure of Manado municipal tends to be monocentric in certain boundary from the city center, but start shifting to polycentric pattern in the peri-urban zone. This characteristic is associated with some potential problems such as acute traffic congestion, air pollution, emerging of slum and squatter and the increased risk of disasters, specifically on downtown area. In the peri-urban zone, the potential significant problems is the phenomenon of sprawling and all its associated impacts such as fragmentation of green open space, increased dependence on private vehicles and increased investment and maintenance costs for infrastructure. [ABSTRACT FROM AUTHOR]

Mass segmentation is one of the fundamental tasks used when identifying breast cancer due to the comprehensive information it provides, including the location, size, and border of the masses. Despite significant improvement in the performance of the task, certain properties of the data, such as pixel class imbalance and the diverse appearance and sizes of masses, remain challenging. Recently, there has been a surge in articles proposing to address pixel class imbalance through the formulation of the loss function. While demonstrating an enhancement in performance, they mostly fail to address the problem comprehensively. In this paper, we propose a new perspective on the calculation of the loss that enables the binary segmentation loss to incorporate the sample-level information and region-level losses in a hybrid loss setting. We propose two variations of the loss to include mass size and density in the loss calculation. Also, we introduce a single loss variant using the idea of utilizing mass size and density to enhance focal loss. We tested the proposed method on benchmark datasets: CBIS-DDSM and INbreast. Our approach outperformed the baseline and state-of-the-art methods on both datasets. [ABSTRACT FROM AUTHOR]

Importance of Insurance is catching up since 1991, but still, some people are not able to buy any kind of insurance product because of poverty. Indian insurance market is growing rapidly, though its size is very small comparing it with USA and China. But it has been expanding in leaps and bounds. In order to know the development and trends in the insurance sector, present paper uses semi log model and Anova techniques. The direct selling brings larger business. Reliance on individual agents had not yet come down. The remarkable sign is that, the business share of corporate agents-bank is increasing though there is no separate team with banks to market the insurance products. Business from new century digital means in the total new business of insurance does not increasing and going beyond 1 per cent. In fact, it should catch up the speed so that insurance companies can save the commission. [ABSTRACT FROM AUTHOR]

In the field of deep-sea positioning, this paper aims to enhance accuracy and computational efficiency in positioning calculations. We propose an improved method based on layered clustering of sound velocity profiles, where the profiles are stratified according to maximum distance and maximum density. Subsequently, a secondary curve fitting is applied to the stratified data. Ultimately, the underwater positioning is conducted using the sound velocity profiles' post-layered fitting. We compare our approach with traditional methods such as k-means clustering, layered clustering, and gradient-based stratification. Experimental results demonstrate that, in the application scenario of a USBL system with a transducer tilted at 30°, and under the premise of autonomously controlling the number of layers, our method significantly improves positioning accuracy. [ABSTRACT FROM AUTHOR]

Purpose: This paper adopts a modified Taguchi approach to develop empirical relationships to the performance characteristics (output responses) in terms of process variables and demonstrated their validity through comparison of test data. The method suggests a few tests as per the orthogonal array and provides complete information for all combinations of levels and process variables. This method also provides the estimated range of output responses so that the scatter in the repeated tests can be assessed prior to the tests. Design/methodology/approach: In order to obtain defect-free products meeting the required specifications, researchers have conducted extensive experiments using powder bed fusion (PBF) process measuring the performance indicators (namely, relative density, surface roughness and hardness) to specify a set of printing parameters (namely, laser power, scanning speed and hatch spacing). A simple and reliable multi-objective optimization method is considered in this paper for specifying a set of optimal process parameters with SS316 L powder. It was reported that test samples printed even with optimal set of input variables revealed irregular shaped, microscopic porosities and improper melt pool formation. Findings: Finally, based on detailed analysis, it is concluded that it is impossible to express the performance indicators, explicitly in terms of equivalent energy density (E_0ˆ*), which is a combination of multiple sets of selective laser melting (SLM) process parameters, with different performance indicators. Empirical relations for the performance indicators are developed in terms of SLM process parameters. Test data are within/close to the expected range. Practical implications: Based on extensive analysis of the SS316 L data using modified Taguchi approach, the optimized process parameters are laser power = 298 W, scanning speed = 900 mm/s and hatch distance = 0.075 mm, for which the results of surface roughness = 2.77 Ra, relative density = 99.24%, hardness = 334 Hv and equivalent energy density is 4.062. The estimated data for the same are surface roughness is 3.733 Ra, relative density is 99.926%, hardness is 213.64 Hv and equivalent energy density is 3.677. Originality/value: Even though equivalent energy density represents the energy input to the process, the findings of this paper conclude that energy density should no longer be considered as a dependent process parameter, as it provides multiple results for the specified energy density. This aspect has been successfully demonstrated in this paper using test data. [ABSTRACT FROM AUTHOR]

This paper focuses on investigating the density convergence of a fully discrete finite difference method when applied to numerically solve the stochastic Cahn–Hilliard equation driven by multiplicative space-time white noises. The main difficulty lies in the control of the drift coefficient that is neither globally Lipschitz nor one-sided Lipschitz. To handle this difficulty, we propose a novel localization argument and derive the strong convergence rate of the numerical solution to estimate the total variation distance between the exact and numerical solutions. This along with the existence of the density of the numerical solution finally yields the convergence of density in L^1(\mathbb {R}) of the numerical solution. Our results partially answer positively to the open problem posed by J. Cui and J. Hong [J. Differential Equations 269 (2020), pp. 10143–10180] on computing the density of the exact solution numerically. [ABSTRACT FROM AUTHOR]

This paper presents the determination method of the exact geographical coordinates of aboveground nuclear tests (NT) epicenters based on the radioecological study results the example of the Semipalatinsk Nuclear Test Site. By testing the NT Epicenter software for determining the exact geographic coordinates of the NT centers, it was established that it is indeed possible to determine the exact coordinates of most of the aboveground NTs. Their locations are currently determined by the presence are currently determined by the presence of technogenic disturbance of the soil surface in the area of the alleged epicenter (the presence of a crater), as well as by comparing maps of radioactive contamination and a space image. The accuracy of the precise coordinates of the NT is highly dependent on the density of the auxiliary grid: the smaller the pitch of the auxiliary grid, the higher the accuracy of the NT epicenter. [ABSTRACT FROM AUTHOR]

This paper reports on an experimental investigation that used a full factorial design to study the main effects and the interaction effect of layer thickness and compaction thickness on the green part density in the binder jetting additive manufacturing of silicon carbide. A two-variable, two-level full factorial design was employed. The results show that the green part density was higher at the low level of layer thickness and at the high level of compaction thickness. These results can be useful in selecting the values of printing variables, enabling the fabrication of green parts with a desirable density that is crucial for advanced ceramic applications. [ABSTRACT FROM AUTHOR]

Porous hierarchical structures are extensively utilized in engineering for their high specific strength, enhanced corrosion resistance, and multifunctionality. Over the past two decades, multiscale topology optimization for these structures has garnered significant attention. This paper introduces a novel hybrid MMCs (Moving Morphable Components)–density topology optimization method for quasi-periodic cellular structures. The term 'quasi-periodic' refers to microstructures whose different macroscopic points exhibit similar topologies with varying parameters. The primary concept involves using the MMC method to describe microstructural topology, while employing variable density to depict macro layouts. This approach leverages the advantage of MMCs in explicitly describing structural topology alongside the variable density of arbitrary microstructures. Sensitivity analyses of the optimization functions concerning design variables are shown, and a gradient optimization solver is employed to solve the optimization model. The examples effectively show the efficacy of the proposed method, illustrating that quasi-periodic cellular structures outperform single-scale solid structures. [ABSTRACT FROM AUTHOR]

By the Bagchi theorem, the Riemann hypothesis (all non-trivial zeros lie on the critical line) is equivalent to the self-approximation of the function ζ (s) by shifts ζ (s + i τ) . In this paper, it is determined that the Riemann hypothesis is equivalent to the positivity of density of the set of the above shifts approximating ζ (s) with all but at most countably many accuracies ε > 0 . Also, the analogue of an equivalent in terms of positive density in short intervals is discussed. [ABSTRACT FROM AUTHOR]

This paper considers nonparametric estimations of a density function in a two-class mixture model. A linear wavelet estimator and an adaptive wavelet estimator are constructed. Upper bound estimations over Lp (1 = p < +∞) risk of those wavelet estimators are proved in Besov spaces. When p̃ = p = 1, the convergence rate of adaptive wavelet estimator is the same as the linear estimator up to a ln n factor. The adaptive wavelet estimator can get better than the linear estimator in the case of 1 = p̃ < p. Finally, some numerical experiments are presented to validate the theoretical results. [ABSTRACT FROM AUTHOR]

Structural graph clustering is a data analysis technique that groups nodes within a graph based on their connectivity and structural similarity. The Structural graph clustering SCAN algorithm, a density-based clustering method, effectively identifies core points and their neighbors within areas of high density to form well-defined clusters. However, the clustering quality of SCAN heavily depends on the input parameters, ϵ and μ , making the clustering results highly sensitive to parameter selection. Different parameter settings can lead to significant differences in clustering results, potentially compromising the accuracy of the clusters. To address this issue, a novel structural graph clustering algorithm based on the adaptive selection of density peaks is proposed in this paper. Unlike traditional methods, our algorithm does not rely on external parameters and eliminates the need for manual selection of density peaks or cluster centers by users. Density peaks are adaptively identified using the generalized extreme value distribution, with consideration of the structural similarities and interdependencies among nodes, and clusters are expanded by incorporating neighboring nodes, enhancing the robustness of the clustering process. Additionally, a distance-based structural similarity method is proposed to re-cluster noise nodes to the correct clusters. Extensive experiments on real and synthetic graph datasets validate the effectiveness of our algorithm. The experiment results show that the ADPSCAN has a superior performance compared with several state-of-the-art (SOTA) graph clustering methods. [ABSTRACT FROM AUTHOR]

Estimating the population in a given scene is a process known as crowd counting. The field has recently garnered significant attention, and many innovative methods have emerged. However, intense scale variations and background interference make crowd counting in realistic scenes always challenging. To address these in this paper, a multi-level attention network with multi-scale feature fusion named MLANet is proposed. The network consists of three sections: a multi-level base feature extraction front-end network, a centralized dilated multi-scale feature fusion mid-end network with a global attention module, and a back-end network for the generation of density maps. By incorporating a flexible attention module and multi-scale features, the method can accurately capture crowd information at different scales and achieve accurate counting results. We evaluated the method on four public datasets (UCF_CC_50, ShanghaiTech, WorldExpo'10, and Beijing BRT), and the experimental results demonstrate a significant reduction in counting error when compared with existing methods. [ABSTRACT FROM AUTHOR]

Alternative sources for an industrial production of essential substances represent an exciting field of study for many researchers. Based on the previous research, itaconic acid and its esters were intensively studied as one of the sources. This paper relates to a determination of the basic physical–chemical properties of bis(2-methylbutyl) itaconate and bis(3-methylbutyl) itaconate that are produced from itaconic acid and 2-methylbutan-1-ol and 3-methylbutan-1-ol, respectively, from biomass. According to our best knowledge, physical–chemical properties of these substances, such as density, viscosity, and saturated vapor pressure, are not presented in the literature, and these are important for the future research of their production. [ABSTRACT FROM AUTHOR]

Understanding active matter has led to new perspectives on biophysics and non-equilibrium dynamics. However, the development of numerical tools for simulating active fluids capable of incorporating non-trivial boundaries or inclusions has lagged behind. Active particle-based methods, which typically excel at this, suffer from large density fluctuations that affect the dynamics of inclusions. To this end, we advance the Active-Nematic Multi-Particle Collision Dynamics algorithm, a particle-based method for simulating active nematics, by addressing the large density fluctuations that arise from activity. This paper introduces three activity formulations that mitigate the coupling between activity and local density. Local density fluctuations are decreased to a level comparable to the passive limit while retaining active nematic phenomenology and increasing the active turbulence regime four-fold in two dimensions. These developments extend the technique into a flexible tool for modeling active systems, including solutes and inclusions, with broad applications for the study of biophysical systems. Particle-based models of soft active matter are known to exhibit large density fluctuations, which may be problematic for considering homogeneous systems. Through considering the coupling of activity to local density, we reduce density fluctuations while retaining active turbulent dynamics. [ABSTRACT FROM AUTHOR]

Beech wood, renowned for its diverse applications spanning construction, flooring, furniture, veneer, and plywood, holds a paramount position among industrial wood species. Nevertheless, the myriad of beech species worldwide, coupled with the dynamic impact of climate change, have produced structural variations within beech trees. Extensive research has scrutinized the physical and mechanical attributes of beech wood species across the globe. Findings reveal distinguishable mechanical strength, yet increased density leads to notable rates of shrinkage and swelling, somewhat constraining its utility in select domains. Identifying research gaps can create new efforts aimed at exploiting the potential of these wood resources. This paper outperforms a mere exploration of beech wood properties over the past two decades; it delves into the ramifications of climatic fluctuations, temperature shifts, wind dynamics, and soil composition. Given the lack of a comprehensive compendium documenting the full range of physical, mechanical, and microscopic attributes of the Fagus genus, this paper aims to compile information that integrates this multifaceted information. [ABSTRACT FROM AUTHOR]

Plastic foams, near-ubiquitous in everyday life and industry, show properties that depend primarily on density. Density measurement, although straightforward in principle, is not always easy. As such, while several methods are available, plastic foam industry is not yet supported with a standard technique that effectively enables to control density maps. To overcome this issue, this paper proposes Terahertz (THz) time-of-flight imaging using normal reflection measurements as a fast, relatively cheap, contactless, non-destructive and non-dangerous way to map plastic foam density, based on the expected relationship between density and refractive index. The approach is demonstrated in the case of polypropylene foams. First, the relationship between the estimated effective refractive index and the polypropylene foam density is derived by characterizing a set of carefully crafted samples having uniform density in the range 70–900 kg/m3. The obtained calibration curve subtends a linear relationship between the density and the refractive index in the range of interest. This relationship is validated against a set of test samples, whose estimated average densities are consistent with the nominal ones, with an absolute error lower than 10 kg/m3 and a percentage error on the estimate of 5%. Exploiting the calibration curve, it is possible to build quantitative images depicting the spatial distribution of the sample density. THz images are able to reveal the non-uniform density distribution of some samples, which cannot be appreciated from visual inspection. Finally, the complex spatial density pattern of a graded foam sample is characterized and quantitatively compared with the density map obtained via X-ray microscopy. The comparison confirms that the proposed THz approach successfully determines the density pattern with an accuracy and a spatial scale variability compliant with those commonly required for plastic foam density estimate. [ABSTRACT FROM AUTHOR]

This article presents the world energy situation, the importance of energy transition, and it further designates hydrogen as a potential replacement for natural gas. Moreover, the paper specifies that the energy transition will be carried out gradually, sustained by conventional resources. Hydrogen can be mixed with natural gasses in current networks, but additional risks must be considered. These risks prove to be minimal in the distribution sector if the hydrogen fraction is kept within acceptable limits, and if optimal operation and safety measures are enforced. The behavior of the hydrogen-natural gas mixture, also called HENG, is studied based on distinguishing the physical and chemical properties of hydrogen and natural gas. In order to analyze the true behavior of the mixture in a distribution network, a numerical simulation was undertaken, whose analysis shows that there is a tight connection between the concentration of hydrogen in the system, consumption, and linepack, and the operational limits of the network must be established based on these data. Knowing the behavior, strategies and regulations can be drafted in order to safely exploit natural gas-hydrogen distribution networks. However, every distribution network has its own particularities, which is why additional studies both at theoretical as well as practical level, performed on real distribution networks, are needed. [ABSTRACT FROM AUTHOR]

The integrals of diffusion processes are of significant importance in the field of finance, particularly in relation to stochastic volatility models, which are frequently employed to represent the temporal variability of stock prices. In this paper, we consider the strong consistency of the nonparametric kernel estimator of the transition density for second-order diffusion processes, using the moment inequalities of ρ-mixing sequences to demonstrate the strong consistency under some regularity conditions. Furthermore, the asymptotic mean square error is provided based on the deviation and variance of the transition density kernel estimator. The optimal bandwidth is found and thus the convergence rate of the kernel estimator is obtained. At the same time, our results are compared with the conclusions of the univariate density function. [ABSTRACT FROM AUTHOR]

Based on a data-driven kernel estimator, Lepski and Willer considered the problem of adaptive Lp risk estimations in the convolution structure density model in 2017 and 2019. This current paper studies the same problem with a data-driven wavelet estimator on Besov spaces, as wavelet estimations offer fast algorithm and provide more local information. Our results can reduce to the traditional adaptive wavelet estimations in the classical density model with no errors, as well as deconvolutional model. [ABSTRACT FROM AUTHOR]

In this paper, we study the asymptotic behaviour of a family of random free-discontinuity energies E ε defined in a randomly perforated domain, as ε goes to zero. The functionals E ε model the energy associated to displacements of porous random materials that can develop cracks. To gain compactness for sequences of displacements with bounded energies, we need to overcome the lack of equi-coerciveness of the functionals. We do so by means of an extension result, under the assumption that the random perforations cannot come too close to one another. The limit energy is then obtained in two steps. As a first step, we apply a general result of stochastic convergence of free-discontinuity functionals to a modified, coercive version of E ε . Then the effective volume and surface energy densities are identified by means of a careful limit procedure. [ABSTRACT FROM AUTHOR]

Curved grid stiffeners, compared to straight stiffeners, offer greater flexibility in adjusting the force transmission paths and give better structural performance. In this paper, a level-set-based density method is employed to generate layouts of curved grid stiffeners so that the critical buckling load factor (BLF) of the stiffened structures is improved. During the optimization process, volume constraint is incorporated to control material utilization, and gradient constraints are employed to maintain uniformity in the width of the stiffeners. Finally, the proposed method is demonstrated through several numerical examples. [ABSTRACT FROM AUTHOR]

This paper represents the Reliable Mobility Management of RPL (RM-RPL) protocol, specifically developed to overcome the limitations of the Routing Protocol for Low-Power and Lossy Networks (RPL) in mobile IoT environments. RM-RPL incorporates a sophisticated mechanism to prevent the formation of loops, enabling mobile nodes to operate as both routers and parents within the network. It introduces a novel objective function that optimizes the selection of parent nodes and includes a mechanism to adjust the protocol's behavior when nodes are stationary. Furthermore, an algorithm is devised to acknowledge critical packets properly. The proposed model provides superior support for mobility, efficient routing, and dependable data transmission, rendering it highly suitable for diverse IoT applications. Through comprehensive evaluations, RM-RPL demonstrates exceptional performance in challenging scenarios characterized by large-scale networks, high density, and dynamic conditions. Comparative analysis reveals that RM-RPL significantly enhances the packet delivery ratio and exhibits commendable power consumption, end-to-end delay, and handover delay. [ABSTRACT FROM AUTHOR]

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In the continuous scaling-up process of the separating system, a mechanism exists that transforms the behavior of the flow field, resulting in deviations from the original model and conclusions. The paper examined the effects of the scale up of a fluidized bed by CFD. It was observed that increasing the diameter reduces the amplitude of axial density fluctuations. Similarly, increasing the static height increases the amplitude. Moreover, increasing the static bed height enhances the visibility of the cyclic flow structure of gas and solid phases. The flow structure in large bed diameters is disrupted. The impact of changing the bed diameter on bed density is more significant than the static height. As the bed diameter increases, the bubble disturbance decreases and the aggregation phase gradually disappears while the proportion of the emulsified phase keeps increasing. This study will guide and assist in the future application of separated fluidized beds in industry. [ABSTRACT FROM AUTHOR]

The present paper deals with effect of exponential density transition on self-focusing of amplitude-modulated laser in plasma. Density of plasma changes due to the ponderomotive nonlinearity which comes into play due to non-uniform spatial profile of laser beam leading to efficient selffocusing. Propagation of amplitude-modulated laser beam is investigated and see the effect of laser intensity and exponential density ramp profile. The beam width parameter of the laser is analyzed with different laser and plasma parameters and strong self-focusing is seen for higher modulation index. [ABSTRACT FROM AUTHOR]

In recent papers, Becke et al. [J. Chem. Phys. 158, 151103 (2023)] and then Becke [J. Chem. Phys. 159, 241101 (2023)] have developed a novel double hybrid density functional, "DH23," whose terms are based on good local physics. Its 12 coefficients are trained on the GMTKN55 (general main-group thermochemistry, kinetics, and noncovalent interactions) chemical database of Goerigk et al. [Phys. Chem. Chem. Phys. 19, 32184 (2017)]. The lowest GMTKN55 "WTMAD2" error to date for any hybrid or double hybrid density functional was obtained (1.73 kcal/mol for the revDH23 variant). Here, we simplify DH23 by introducing a dispersion damping scheme involving atomic numbers only and one global parameter. The resulting new functional, "DH24," performs as well as its predecessors. [ABSTRACT FROM AUTHOR]