Search Results (17)

Objective: This study aimed to evaluate the relationship between craniocervical posture and skeletal malocclusion patterns in adolescents. Methods: This cross-sectional study included 80 adolescents aged 10–15 years diagnosed with skeletal Class I, Class II Division 1, Class II Division 2, or Class III malocclusion. Postural parameters—Sagittal Head Angle (SHA), Craniocervical Angle (CA), and Shoulder Angle (SA)—were assessed using standardized sagittal-plane digital photographs obtained in Natural Head Position. Skeletal classification and cephalometric measurements (SNA°, SNB°, ANB°, GoGn/SN°, and Occlusal Plane/SN°) were determined from lateral cephalometric radiographs. Intergroup comparisons were performed using the Kruskal–Wallis test, and posture–skeletal relationships were evaluated using Pearson and Spearman correlation analyses (p < 0.05). Results: No significant differences were observed in postural parameters among skeletal malocclusion classes (p > 0.05). In the overall sample, SHA showed weak negative correlations with SNA° (r = −0.284, p < 0.01) and SNB° (r = −0.381, p < 0.01), and a weak positive correlation with Occlusal Plane/SN° (r = 0.235, p < 0.05). No significant associations were identified for CA or SA. Subgroup analysis demonstrated that these associations were present exclusively in the Class II Division 2 group, where SHA showed strong negative correlations with both SNA° (r = −0.653, p < 0.01) and SNB° (r = −0.605, p < 0.01). Conclusions: Sagittal head posture may show phenotype-specific associations during adolescence, particularly in Class II Division 2 malocclusion. Incorporating postural assessment into orthodontic evaluation may enhance diagnostic understanding during growth. Full article

In order to solve the problem that electric forklifts are prone to rollover when turning, a coordinated control strategy for anti-rollover of electric forklifts is proposed. A forklift dynamics simulation model with integrated centroid position is constructed, the stability of the forklift is judged by the phase plane area division method, the upper controller, including the active steering controller, and the differential brake controller are designed, the control weight coefficient of the active steering controller and the differential brake controller in different control domains is determined through the coordination controller, so as to obtain the required additional rear wheel rotation angle and additional yaw torque, and the braking force distribution controller exerts braking force to the wheel according to the additional yaw torque. A simulation model is built to verify the effectiveness of this control strategy, and the simulation results show that the control strategy can greatly reduce the risk of rollover when the forklift is cornering and further improve the stability of the forklift. Full article

An Arabidopsis sterol mutant, smt2 smt3, defective in sterolmethyltransferase2 (SMT2), exhibits severe growth abnormalities. The loss of C-24 ethyl sterols, maintaining the biosynthesis of C-24 methyl sterols and brassinosteroids, suggests specific roles of C-24 ethyl sterols. We characterized the subcellular localizations of fluorescent protein-fused sterol biosynthetic enzymes, such as SMT2-GFP, and found these enzymes in the endoplasmic reticulum during interphase and identified their movement to the division plane during cytokinesis. The mobilization of endoplasmic reticulum-localized SMT2-GFP was independent of the polarized transport of cytokinetic vesicles to the division plane. In smt2 smt3, SMT2-GFP moved to the abnormal division plane, and unclear cell plate ends were surrounded by hazy structures from SMT2-GFP fluorescent signals and unincorporated cellulose debris. Unusual cortical microtubule organization and impaired cytoskeletal function accompanied the failure to determine the cortical division site and division plane formation. These results indicated that both endoplasmic reticulum membrane remodeling and cytokinetic vesicle transport during cytokinesis were impaired, resulting in the defects of cell wall generation. The cell wall integrity was compromised in the daughter cells, preventing the correct determination of the subsequent cell division site. We discuss the possible roles of C-24 ethyl sterols in the interaction between the cytoskeletal network and the plasma membrane. Full article

The Ebinur Lake Basin is a typical terrestrial sedimentary Basin in Northwest China that has developed a piedmont distributive fluvial system (DFS) sedimentary environment, lake sedimentary environment, and desert sedimentary environment. The Ebinur Lake receives the sediments carried by the rivers in the basin and is the regional sedimentary center. In this study, a division scheme of modern sedimentary system tracts in the Ebinur Lake Basin was proposed. According to the landform, sedimentary environment, structure, and sedimentary system types, the Ebinur Lake Basin was divided into five system tracts. The area with high altitude and steep gradients mainly develops the rapid sedimentary system DFS, and the area with the lowest altitude in the region develops the lake sedimentary system. The main action area of climate drought and wind field is the dune sedimentary area. The wind field under the influence of hydrological climate and geomorphology has an important influence on the distribution of the sedimentary system tract. The structure determines the development of different types of sedimentary systems by controlling the topographic fluctuation and sedimentary space. Hydroclimate and geomorphology affect the development of sedimentary systems by controlling the sediment source rate in the sedimentary area. Based on the analysis of the characteristics and distribution of the modern sedimentary system in the Ebinur Lake Basin, a method for determining the level of the sedimentary system of the Ebinur Lake was established together with a plane model of the sedimentary system of the Ebinur Lake, which provides a reference for the study of the sedimentary system of continental basins. Full article

The advancement of remote sensing has enabled the creation of high-resolution Digital Elevation Models (DEMs). Topographic features such as slope gradient (SG), local convexity (LC), and surface texture (ST), derived from DEMs, are related to subsurface geological conditions. In South Korea, bedrock depth (D_bedrock) and the average shear wave velocity of soil (V_Ssoil) serve as metrics for determining the site class, which represents the degree of site amplification in seismic design criteria. These metrics, typically measured through geotechnical and geophysical investigations, require predictive methods for preliminary estimation over large areas. Previous studies developed an automatic terrain classification (AC) scheme using SG, LC, and ST, and subsequent research revealed that terrain classification effectively represents subsurface conditions such as D_bedrcok and average shear wave velocity down to 30 m depth. However, AC intrinsically depends on the regional features of DEMs, dividing regions based on nested means of topographic features (SG, LC, and ST). In this study, we developed two terrain classification methods to determine the thresholds of class divisions, aiming to optimize D_bedrock and V_Ssoil predictions: Sequentially Optimized Classification (SOC) and Non-Sequentially Optimized Classification (NOC). Through the study of the sensitivity of terrain classification methods, smoothing levels, and threshold levels for terrain class generation, we identified the best classification method by comparing it with the geological and mountainous region distribution. Subsequently, we developed DEM-dependent regression models for each class to enhance the accuracy of predicting D_bedrock and V_Ssoil. The main findings of this study are: (1) the terrain class map suggested in this study represents the distribution of alluvial plane and mountainous regions well, and (2) the DEM calibration for each class provides increased accuracy of D_bedrock and V_Ssoil predictions in South Korea. We anticipate that the terrain class map, along with D_bedrock and V_Ssoil maps, will be effectively utilized in geological interpretations and land-use planning for seismic design. Full article

The article presents the differences in some physical and chemical properties of wood with false heartwood, mature wood, and sapwood of Fagus sylvatica L.: density of wood in the dry state, color in the color space CIE L*a*b* on the tangential surface and the planed surface at w = 10 ± 0.5%, as well as moisture and acidity of wet wood. As part of chemical analyses, the relative proportion of cellulose, hemicelluloses, lignin, and extractive substances in individual zones of beechwood in trunks with false heartwood was determined. From the carried out analyses, it follows that the biggest difference between the wood of false heartwood, mature wood, and sapwood is the color of the wood. The red-brown color of the wood with false heartwood in the color space CIE L*a*b* is described by the following coordinate values: L* = 64.9 ± 4.9; a* = 12.9 ± 1.4; b* = 19.6 ± 1.7. The most significant differences between the values of the color space are on the lightness coordinate, where the light ochre-white of mature wood shows a decrease of ∆L* = −14.0 compared with the color of false heartwood, and the white—pale grey color of sapwood shows a decrease of ∆L* = −17.5. The density of dry beechwood with false heartwood is higher by ∆ρ₀ = 4.7% than the density of mature wood, and the density of sapwood is ∆ρ₀ = 12.3% lower than the density of wood with false heartwood. The exact opposite applies to the acidity of wet beechwood. The results of wet wood acidity measurements also point to certain differences. While the acidity of the wet wood of false heartwood is pH = 5.32 ± 0.13, the acidity of the sapwood is 5.1% lower. The higher acidity of beech heartwood is attributed to the presence of organic acids in polyphenols during heartwood formation. From the comparison of the representation of cellulose, hemicellulose, lignin, and extractive substances, it follows that the relative content of lignin and hemicelluloses is higher in false heartwood than in mature wood and sapwood. On the contrary, the content of holocellulose and cellulose is highest in sapwood. The presented divisions in the physical and chemical properties of beechwood with false heartwood do not limit the use of beechwood in industrial applications, except for a change in color; the definition of color boundaries in the color space CIE L*a*b* creates space for sorting beechwood according to color and can be used to increase the color variety of compositions of construction-carpentry products. Full article

A safety and arming device with a condition feedback function has been designed in this article to improve the intelligence and safety of ignition devices. The device achieves active control and recoverability by virtue of four groups of bistable mechanisms which consist of two electrothermal actuators to drive a semi-circular barrier and a pawl. According to a specific operation sequence, the barrier is engaged by the pawl at the safety or the arming position. The four groups of bistable mechanisms are connected in parallel, and the device detects the contact resistance generated by the engagement of the barrier and pawl by the voltage division of an external resistor to determine the parallel number of the mechanism and give feedback on the device’s condition. The pawl as a safety lock can restrain the in-plane deformation of the barrier in the safety condition to improve the safety function of the device. An igniter (a NiCr bridge foil covered with different thicknesses of Al/CuO films) and boron/potassium nitrate (B/KNO₃, BPN) are assembled on both sides of the S&A device to verify the safety of the barrier. The test results show that the S&A device with a safety lock can realize the safety and arming functions when the thickness of the Al/CuO film is set to 80 μm and 100 μm. Full article

A novel method and description of creating diversified complex original building forms roofed with a number of transformed folded shell units developed on the basis of a novel reference polyhedral network and arranged according to a reference surface with the negative Gaussian curvature is presented. For that purpose, specific reference polyhedral networks is are defined as a complex material deliberately composed of many regular tetrahedrons that are arranged regularly to obtain original attractive complex general building forms. The proposed method is a significant extension of the previous method for shaping roof structures with the positive Gaussian curvature and fills existing gaps in current scientific knowledge. The extended method enables the designer to significantly increase the variety of the created complex shell roof forms and plane-walled folded elevation forms of buildings and to define the shapes of their rod structural systems. It allows one to overcome the existing significant geometric and material limitations related to shape transformations of nominally flat rectangular folded steel sheets into different shell forms. The developed extension is based on formation of a set of properly connected tetrahedra as a material determining different (a) inclination of elevation walls to the vertical, and (b) distribution of many individual warped roof shells in accordance with the properties of a regular surface with negative Gaussian curvature. A number of the adopted specific sets of division coefficients (parameters) is used for determining the entire network and its complete tetrahedra. The presented description makes it possible to adopt appropriate assumptions and data and then employ the innovative method to obtain the expected characteristics of the unconventional building form shaped. The presented three different special forms created with the help of the novel method and the appropriately selected diversified values of the division coefficients of pairs of the vertices of a polyhedral reference network, a polygonal eaves network and points of a reference surface confirm the innovative scientific nature of the obtained results. The method has to be computationally aided due to the complexity of mathematical operations and the need to visualize the designed forms. Full article

The design of solid-state lighting is vital, as numerous metrics are involved in their exact positioning, and as it is utilized in various processes, ranging from intelligent buildings to the internet of things (IoT). This work aims to determine the power and delay spread from the light source to the receiver plane. The positions of the light source and receiver were used for power estimation. We focus on analog orthogonal frequency-division multiplexing (OFDM) in visible light communication (VLC) and assess the area under the curve (AUC). The proposed system was designed using modulation techniques (i.e., quadrature amplitude modulation; QAM) for visible light communication (VLC) and pulse-width modulation (PWM) for dimming sources. For the positioning and spreading of brightness, the proof-of-concept was weighted equally over the entire area. Therefore, the receiver plane was analyzed, in order to measure the power of each light-emitting diode (LED) in a given area, using the delayed mean square error (MSE). A framework was applied for the placement of LEDs, using full-width at half-maximum (FWHM) parameters with varying distances. Then, the received power was confirmed. The results show that the AUC using DRMS values for LEDs significantly increased (by $30\%$) when the number of source LEDs was changed from four to three. These results confirm that our system, associated with the simple linear lateration estimator, can achieve better energy consumption. Full article

This article is an insight into interdisciplinary topics in the field of civil engineering, morphology, architecture, mechanics, and computer programming. A novel method for shaping unconventional complex roofs in which regular folded units transformed into various shells are used as a complex substitute material is proposed. The original method’s algorithm for building systems of planes defining diversified polyhedral networks in the three-dimensional space by means of division coefficients of the subsequently determined vertices is presented. The algorithm is based on the proportions between the lengths of the edges of the reference network, the location and shape of the ruled shell units included in the designed complex roof structure, so it is intuitive. The shell units are made up of nominally flat folded sheets transformed effectively into shell forms whose static-strength properties are controlled by geometric quantities characteristic of ruled surfaces. The presented original approach to the shaping of the shell roof structures determining specific complex building forms allows us to go beyond the limitations related to the orthotropic structure of the folded roof sheeting and the shape transformations. Full article

Nowadays, there is an increasing interest in smart systems, e.g., smart metering or smart spaces, for which active sensing plays an important role. In such systems, the sample or environment to be measured is irradiated with a signal (acoustic, infrared, radio-frequency…) and some of their features are determined from the transmitted or reflected part of the original signal. In this work, infrared (IR) signals are emitted from different sources (four in this case) and received by a unique quadrature angular diversity aperture (QADA) sensor. A code division multiple access (CDMA) technique is used to deal with the simultaneous transmission of all the signals and their separation (depending on the source) at the receiver’s processing stage. Furthermore, the use of correlation techniques allows the receiver to determine the amount of energy received from each transmitter, by quantifying the main correlation peaks. This technique can be used in any system requiring active sensing; in the particular case of the IR positioning system presented here, the relative amplitudes of those peaks are used to determine the central incidence point of the light from each emitter on the QADA. The proposal tackles the typical phenomena, such as distortions caused by the transducer impulse response, the near-far effect in CDMA-based systems, multipath transmissions, the correlation degradation from non-coherent demodulations, etc. Finally, for each emitter, the angle of incidence on the QADA receiver is estimated, assuming that it is on a horizontal plane, although with any rotation on the vertical axis Z. With the estimated angles and the known positions of the LED emitters, the position (x, y, z) of the receiver is determined. The system is validated at different positions in a volume of 3 × 3 × 3.4 m³ obtaining average errors of 7.1, 5.4, and 47.3 cm in the X, Y and Z axes, respectively. Full article

The distribution of highly de-esterified homogalacturonans (HGs) in dividing protodermal cells of the monocotyledon Zea mays, the dicotyledon Vigna sinensis, and the fern Asplenium nidus was investigated in order to examine whether the cell wall region adjoining the preprophase band (PPB) is locally diversified. Application of immunofluorescence revealed that de-esterified HGs were accumulated selectively in the cell wall adjacent to the PPB in: (a) symmetrically dividing cells of stomatal rows of Z. mays, (b) the asymmetrically dividing protodermal cells of Z. mays, (c) the symmetrically dividing guard cell mother cells (GMCs) of Z. mays and V. sinensis, and (d) the symmetrically dividing protodermal cells of A. nidus. A common feature of the above cell types is that the cell division plane is defined by extrinsic cues. The presented data suggest that the PPB cortical zone-plasmalemma and the adjacent cell wall region function in a coordinated fashion in the determination/accomplishment of the cell division plane, behaving as a continuum. The de-esterified HGs, among other possible functions, might be involved in the perception and the transduction of the extrinsic cues determining cell division plane in the examined cells. Full article

Kinesin-12 family members are characterized by an N-terminal motor domain and the extensive presence of coiled-coil domains. Animal orthologs display microtubule plus-end directed motility, bundling of parallel and antiparallel microtubules, plus-end stabilization, and they play a crucial role in spindle assembly. In plants, kinesin-12 members mediate a number of developmental processes including male gametophyte, embryo, seedling, and seed development. At the cellular level, they participate in critical events during cell division. Several kinesin-12 members localize to the phragmoplast midzone, interact with isoforms of the conserved microtubule cross-linker MICROTUBULE-ASSOCIATED PROTEIN 65 (MAP65) family, and are required for phragmoplast stability and expansion, as well as for proper cell plate development. Throughout cell division, a subset of kinesin-12 reside, in addition or exclusively, at the cortical division zone and mediate the accurate guidance of the phragmoplast. This review aims to summarize the current knowledge on kinesin-12 in plants and shed some light onto the heterogeneous localization and domain architecture, which potentially conceals functional diversification. Full article

The application of Light Detection And Ranging (LiDAR) technology has become increasingly extensive in tunnel structure monitoring. The proposed processing method aims to carry out non-contact monitoring for circular stormwater sewage tunnels and provides an efficient workflow. This allows the automatic processing of raw point data and the acquisition of visualization results to analyze the health state of a tunnel within a short period of time. The proposed processing method employs a series of algorithms to extract the point cloud of a single tunnel segment without obvious noise by main three steps: axis acquisition, segment extraction, and denoising. The tunnel axis is extracted by fitting boundaries of the tunnel point cloud projection in the plane. With the guidance of the axis, the entire preprocessed tunnel point cloud is segmented by equal division to get a section of the tunnel point cloud which corresponds to a single tunnel segment. Then, the noise in every single point cloud segment is removed by clustering the algorithm twice, based on the distance and intensity. Finally, clean point clouds of tunnel segments are processed by an effective deformation extraction processor to determine the ovality and to get a three-dimensional visual deformation nephogram. The proposed method can significantly improve the efficiency of LiDAR data processing and extend the application of LiDAR technology in circular stormwater sewage tunnel monitoring. Full article

Semantically rich indoor models are increasingly used throughout a facility’s life cycle for different applications. With the decreasing price of 3D sensors, it is convenient to acquire point cloud data from consumer-level scanners. However, most existing methods in 3D indoor reconstruction from point clouds involve a tedious manual or interactive process due to line-of-sight occlusions and complex space structures. Using the multiple types of data obtained by RGB-D devices, this paper proposes a fast and automatic method for reconstructing semantically rich indoor 3D building models from low-quality RGB-D sequences. Our method is capable of identifying and modelling the main structural components of indoor environments such as space, wall, floor, ceilings, windows, and doors from the RGB-D datasets. The method includes space division and extraction, opening extraction, and global optimization. For space division and extraction, rather than distinguishing room spaces based on the detected wall planes, we interactively define the start-stop position for each functional space (e.g., room, corridor, kitchen) during scanning. Then, an interior elements filtering algorithm is proposed for wall component extraction and a boundary generation algorithm is used for space layout determination. For opening extraction, we propose a new noise robustness method based on the properties of convex hull, octrees structure, Euclidean clusters and the camera trajectory for opening generation, which is inapplicable to the data collected in the indoor environments due to inevitable occlusion. A global optimization approach for planes is designed to eliminate the inconsistency of planes sharing the same global plane, and maintain plausible connectivity between the walls and the relationships between the walls and openings. The final model is stored according to the CityGML3.0 standard. Our approach allows for the robust generation of semantically rich 3D indoor models and has strong applicability and reconstruction power for complex real-world datasets. Full article