Position Of Elements Research Articles

Position detection of elements in off-axis three-mirror space optical system based on ResNet50 and LSTM

Position detection of elements, especially with high-precision and high-efficiency, continue to present challenges in the off-axis three-mirror space optical system to ensure the imaging quality. To test the position of elements in an off-axis three-mirror system, a method based on ResNet50 and Long short-term memory (LSTM) is proposed in this paper. In the proposed method, point spread function (PSF) with different fields of view is extracted as a high dimensional feature vector by the ResNet50 network to achieve high efficiency. The same position information in the high dimensional feature vector from different image plane is obtained by the LSTM module to achieve high precision. To evaluate the performance of the proposed method, three examples of position detection were conducted. The results indicated that the probabilities of achieving detection accuracy better than 10 µm for eccentricity and 10'’ for tilt, across single-dimensional variation of components, multi-dimensional random variation, and detector variation, are 100%, 94%, and 100%, respectively. Unlike the other detection method, the positions of elements are obtained with only one calculation and are close to the final results, which saves both time and resources for adjustment. The findings indicate that the method is an accurate and effective method for detecting position of elements in off-axis three-mirror space optical system.

INVESTIGATION OF GEOMETRIC PARAMETERS ON FLAP AND SLAT AERODYNAMICS IN A THREE-ELEMENT AIRFOIL

Three-element airfoils are commonly employed in airplanes to provide additional lift, reduce runway length requirements, and improve cargo capacity. Due to the small distances between its components and flow interactions, the three-element airfoil has complex flow dynamics. The aerodynamic characteristics of an airfoil system comprising of three elements are greatly influenced by the geometric positioning of the flap and slat. The present study uses the computational techniques to examine how the geometric characteristics affect the aerodynamics of specific pieces, particularly the flap and slat. In this work, computational techniques are used to examine how geometric characteristics, particularly those affecting the flap and slat, affect the aerodynamics of individual components of the multielement airfoil. The chosen design space is generated through the sampling based on the Sobol sequence. The flow physics around each element due to the change in position of individual elements of the three-element airfoil is investigated in detail. Furthermore, it was shown that the leading-edge components greatly influence the flow behavior of the trailing edge components, while the opposite is not significant. Finally, the study reveals that the most significant effect on the aerodynamics characteristics of the three-element airfoil is governed by the gap in the flap.

Recent Progress in Atomically Precise Cu-M Alloy Nanoclusters.

Metal nanoclusters (NCs) with dimensions of approximately 3 nm serve as a crucial link between metal-organic complexes and metal nanoparticles, garnering significant interest due to their distinctive molecule-like characteristics. These include well-defined molecular structures, clear HOMO-LUMO transitions, quantized charge, and robust luminescence emission. Atomically precise alloy NCs, in contrast to homometallic NCs, exhibit a wealth of structures and intriguing properties, with their novel attributes often intricately tied to the positions of alloyed elements within the structure, facilitating the exploration of structure-property relationships. A notable subgroup within this category comprises Cu-M (where M represents metals such as Au, Ag, Rh, Ir, Pd, Pt, Zn, Al etc.) alloy NCs. In this review, we initially outline recent advancements in the development of efficient synthetic techniques for Cu-M alloy NCs, emphasizing the underlying physical and chemical properties that enable precise control over their sizes and surface characteristics. Subsequently, we delve into recent progress in structural elucidation techniques for Cu-M alloy NCs. This structural insight is instrumental in comprehensively understanding the structure-property correlations at the molecular level. Finally, we showcase various examples of Cu-M alloy NCs to illustrate their photoluminescent and catalytic properties, shedding light on their diverse functionalities and potential applications.

EXODONTIA DE TERCEIROS MOLARES INFERIORES: DESAFIOS E COMPLEXIDADES CIRÚRGICAS

Third molar extraction is one of the procedures within the dental clinic that causes people the most fear, despite being performed frequently. The incidence of complications can still be considered high. The anatomical position of these dental elements is one of the main reasons for complications during their removal, due to the proximity of important anatomical structures. Therefore, the use of radiographic examinations to evaluate the positioning of third molars is essential so that it is possible to visualize ways to conduct the surgery safely. The aim of this work is to review, according to the bibliographic literature, the risks of complications during extraction of lower 3rd molars. For this, a search was carried out in the literature, in the following databases: Pubmed, Virtual Health Library (VHL), Scielo and Google Scholar, using the descriptors: “Nonerupted tooth”, “Third Molar” and “Oral Surgery ”. The established inclusion criteria include articles that address the defined theme and that are available for full reading, in Portuguese and English, published in the last 10 years. The exclusion criteria were articles that deviate from the proposed topic, repeated articles and incomplete research. The present work is expected to acquire information to better perform surgeries on third molars according to their clinical condition, presenting ideal approaches for diagnosis and surgical planning and emphasizing the care necessary to avoid surgical complications. Keywords: Tooth Unerupted. Third Molar. Oral Surgery.

Ragam Budaya dan Kekayaan Ekologi sebagai Potensi Pengembangan Wellness Tourism di Kalimantan Timur; Studi Kelembagaan Masyarakat Kutai Adat Lawas Sumping Layang Kedang Ipil Kutai Kartanegara.

Post-pandemic COVID-19 has highlighted wellness tourism as a promising niche in Indonesia, driven by increased health awareness and supported by initiatives like the CHSE (Cleanliness, Health, Safety, and Environmental Sustainability) Protocols. East Kalimantan, with its unique cultural and natural heritage, offers significant potential for wellness tourism development. This study evaluates the cultural richness, ecological assets, and opportunities for wellness experiences in East Kalimantan, emphasizing the role of community engagement in economic empowerment, cultural preservation, and environmental management.Using a qualitative approach with descriptive analysis, the research includes key informant interviews with cultural leaders of Kutai Adat Lawas Sumping Layang in Kedang Ipil, supplemented by direct observation and secondary data. Thematic analysis and data triangulation ensure validity and provide insights into the role of customary institutions in wellness tourism. The findings identify traditional practices, such as Belian Namang and Nutuk Beham, as unique wellness experiences. The ecological assets, including village and customary forests integral to local livelihoods, present holistic wellness opportunities. Customary community structures are crucial in preserving traditions and supporting wellness tourism as a sustainable product. The integration of cultural and ecological elements positions Kedang Ipil, Kutai Kartanegara, as a strategic site for wellness tourism, fostering sustainable development through cultural heritage and environmental

An educational computational program for nonlinear geometric analysis of truss structures using the Finite Element Method based on Positions

This study describes an educational computational program for the analysis of truss structures using the Finite Element Method based on Positions (FEMP). FEMP adopts the nodal positions of discretized elements as degrees of freedom, in contrast to the displacements used in conventional Finite Element Method (FEM). This approach enables FEMP to straightforwardly and naturally incorporate geometric nonlinearity into its positional formulation, simplifying the nonlinear geometric analysis of structures. The developed educational program provides a range of functionalities, allowing users to conduct both static and dynamic analyses of truss structures.

Generative approach to the structure of negative sentences in Albanian

Abstract This paper examines the components of negative sentences in Albanian from the perspective of generative linguistics. Main aim is to analyze the functions and positions of negative elements in the structure of Albanian sentences, providing a comparison with other languages to highlight the universal features and specificities of Albanian. The focus of the analysis are the main negative particles such as “ nuk ”, “ s ’”, “ mos ”, and “ as ”, which are used to express simple and compound negation, including double and intensive negation. Elements such as “ nuk ” and “ s ’” are positioned immediately before the verb to express a simple negation and operate in a C-command relation that blocks the placement of other elements between them and the verb. In the syntactic structure, their position is above the subject and immediately before the predicate, blocking any other element from being placed between them and the verb. While “ mos ” is used mainly in the imperative, subjunctive and imperative moods, taking position before the modal particle or auxiliary verb to control the actions of the verb. “ As ” reinforces negation and can be positioned before the verb or other constituents to create polynegative structures. Comparisons with languages such as Italian and English emphasize that Albanian has developed polynegative structures, which allow the use of multiple negative elements without violating the grammaticality of the sentence. This analysis suggests that Albanian, through complex negation structures, complies with some of the universal principles of generative linguistics, while simultaneously maintaining special features that challenge some assumptions of standard generative syntax.

Measuring the Benefits of Plants: Visual Exposure and Human Well-being Impacts of Lush Streetscapes

Abstract This research seeks to explore how exposure to horticultural elements in the streetscape may impact cardiovascular health and well-being. We used advanced facial expression and heat-mapping technology software to compare preconscious levels of attentiveness, gaze path, facial expressions, and fixation on images (emotional responses) with and without horticultural elements among 47 adult participants. We found that the position and existence of Lush green elements were significantly related to these biological responses. Barren images were found to elicit a more frequent negative emotional response. This study presented the relationship between horticultural elements and users' conscious and unconscious responses to Lush versus Barren images of street scenes. Key fixation points were correlated with a reduction in stress levels. This finding suggests that including these elements in landscape design could improve well-being.

A Flexible Mold for Facade Panel Fabrication

Architectural surface panelling often requires fabricating molds for panels, a process that can be cost-inefficient and material-wasteful when using traditional methods such as CNC milling. In this paper, we introduce a novel solution to generating molds for efficiently fabricating architectural panels. At the core of our method is a machine that utilizes a deflatable membrane as a flexible mold. By adjusting the deflation level and boundary element positions, the membrane can be reconfigured into various shapes, allowing for mass customization with significantly lower overhead costs. We devise an efficient algorithm that works in sync with our flexible mold machine that optimizes the placement of customizable boundary element positions, ensuring the fabricated panel matches the geometry of a given input shape: (1) Using a quadratic Weingarten surface arising from a natural assumption on the membrane's stress, we can approximate the initial placement of the boundary element from the input shape's geometry; (2) we solve the inverse problem with a simulator-in-the-loop optimizer by searching for the optimal placement of boundary curves with sensitivity analysis. We validate our approach by fabricating baseline panels and a facade with a wide range of curvature profiles, providing a detailed numerical analysis on simulation and fabrication, demonstrating significant advantages in cost and flexibility.

Hybrid Sparse Array Design Based on Pseudo-Random Algorithm and Convex Optimization with Wide Beam Steering

In this paper, a hybrid optimization method utilizing a pseudo-random algorithm and convex optimization is proposed to avoid grating lobe and achieve lower side lobe level (SLL) of a planar sparse array when the minimum inter-element distance is one wavelength. The pseudo-random algorithm is utilized to distribute the positions of elements. The convex algorithm is utilized to optimize the excitations of elements. The results show that a planar sparse array with no grating lobe and peak side lobe level (PSLL) of −17 dB can be obtained with a minimum inter-element distance of one wavelength, which indicates the effectiveness of the hybrid optimization method. In addition, beam steering can be achieved within an 80∘ field of view range.

Mitigation of electric field near overhead transmission lines using electromechanical compensation based on genetic algorithm

The electrical field is a function of both the voltage and the configuration of the overhead transmission line (OTL); thus, mitigation of the electrical field could be achieved by either electrical compensation or mechanical rearrangement of the line configuration. In the mechanical rearrangement method, the conductor positions are optimized under certain constraints so that the electrical field has the minimum possible value. In the proposed research, OTL mechanical rearrangement is improved using electrical compensation based on a genetic algorithm (GA). The electrical compensation is implemented by inserting a combination of passive series and shunt elements in each phase, creating an electric voltage imbalance. GA is an evolutionary optimization algorithm used to minimize the electric field near residences as a fitness function. The positions of conductors and passive-reactive elements are represented as genes. In addition, this paper includes a case study on a 500-kV high-voltage overhead transmission line. The results show that when passive-reactive compensation is combined with mechanical compensation, the lowest electric field can be obtained. Electrical compensation improves the mechanical rearrangement method by approximately 18.6% (the total reduction with mechanical compensation of only about 34% is increased to more than 52% with electromechanical compensation).

Ball Bearing Dynamic Stiffness Prediction Considering an Uncertain Position of Rolling Elements

Abstract This paper considers the challenge of calculating accurate ball bearing stiffness, which is attributed to the uncertainty in the rolling element positions; and it solves that issue based on the simultaneous consideration of these positions and the physical effects of the rotating components. The novelty of the paper consists of the suggested methodology to resolve the uncertainty of the rolling element circumferential position when calculating bearing stiffness. The problem is solved through various formulations of dry and lubricated contact and validated based on the consideration of the finite-element (FE) model. The algorithms presented in the paper allow for the calculation of the resulting stiffness based on the stiffness values evaluated through different ball bearing positions. The approach presented in the paper is validated based on the experimental data. For this purpose, the model of the rotor in ball bearings is built, along with further calculation of the rotor dynamics. The comparison of the critical speeds calculated for the rotor in bearings, which have stiffness evaluated by the proposed approach with the measurements for the real machine, indicates a high accuracy of the suggested method in comparison with the methods that consider the single position of the rolling element when estimating their stiffness. In the paper, further recommendations for the use of the presented method are given, which will be useful for engineers in the field of turbomachinery dynamics.

Effect of manufacturing tolerances on Micro-CPV assemblies: A quantitative approach based on statistical modeling

In micro-concentrator photovoltaics (micro-CPV) minimized components as cells (<1 × 1 mm2) and lenses are used, promising significant cost reductions through parallel manufacturing and reduced material volumes. However, tolerances, such as deviations from nominal size, geometry or position, impact module performance, especially for non-ideal alignment towards the sun. To study the interplay of different, independent tolerances and their effects on current generation, a comprehensive parameter study is practically not feasible, because of the vast number of possible combinations. In this work, we introduce a novel method for assessing tolerances by employing a Monte-Carlo approach to randomly select and combine tolerances in a cell-lens unit. It allows to identify relevant tolerances and quantitatively assess their influence on module performance, namely optical efficiency, and photocurrent as function of angle of incidence and, thus, acceptance angle. We apply the model to a micro-CPV module developed at Fraunhofer ISE and use tolerance distributions based on measurements. We find that the most crucial parameter is the position of the secondary optical element. Given the measured tolerance distributions, the acceptance angles for 90 % of the cases are above 0.5° for 10 % current loss. The developed approach is a crucial tool for identifying and assessing critical tolerances within a manufacturing line, facilitating techno-economic optimization of design and manufacturing processes.

Code Recommendation for Schema Evolution of Mimic Storage Systems

Schema evolution of mimic storage systems is a time-consuming and error-prone task due to the redundant development of heterogeneous executors. The ORM-based proxy requires an entire class to represent the structure of a data table. There lacks domain-specific code recommendation techniques to boost storage development. To address this issue, we design a novel type of code context, i.e. schema context, that combines features of code text, syntax and structure. Regarding the requirements of class-level granularity, we focus on behavior and attribute in code syntax, and use element position and structural metrics to mine the hidden relationships. Based on schema context and an existing inference mode, we propose SchemaRec to recommend ORM-related class for the database executors once one of them has been changed. We conduct experiments with 110 open-source projects, and the results show that SchemaRec obtains more accurate results than Lucene, DeepCS, QobCS and SEA in terms of Top-1, Top-10 and MRR accuracy due to the better ability of context representation. We also find that code syntax is the most important information because it involves behavior and attribute information of ORM-related classes.

Identification of position, size and dynamic heat power of chips embedded in a real electronic board

Temperature is a critical factor in the lifespan of electronic systems. Therefore, it is essential to control all thermal parameters. In certain applications, such as commercial off-the-shelf (COTS) components, manufacturers may not have precise knowledge of the composition of electronic boards. As a result, it is important for them to define the positions of heat-dissipating elements, and the power dissipated to better predict the final thermal behavior of the system. Some electronic boards today even have components integrated into their volume. Since components can now be located not only on the surface but also within the volume of electronic boards, manufacturers need to define volume-based methods for detecting these heat sources. In this article, we address the problem of detecting sources within a volume using surface temperature data. To achieve this goal, we develop a representative numerical model of the system that can be used for an inverse source identification procedure. In a first time, we present a numerical approach that demonstrates the feasibility of the identification procedure on a board containing several electronic chips. Secondly, the volume source identification method is applied to a real case, using surfaces temperatures measured by infrared cameras. The experimental results obtained are consistent and show that this technique is suitable for detecting volumetric sources within an electronic board.

Computational Models of Dynamic Load Sources for Modeling of Construction Structures Operation Used in Monitoring of Technical Condition of Buildings and Structures

This research aims to develop principles for assessing the impact of mega-cyclic vibrodynamic loads on the reliability of construction structures. The relevance of the reasons for the development and improvement of algorithms for numerical modeling of multicycle dynamic loads on building structures is due to the steadily increasing intensity of such loads on buildings and structures in megacities, as well as the acute practical problem of significant differences in the dynamic characteristics of buildings and structures obtained as a result of mathematical modeling and determined by experimental methods. The article presents research materials on computational equivalent models of dynamic load sources for numerical modeling of the behavior of construction structures under their influence, using the method of vibroacoustic analogies. The article examines models of sources of dynamic impact on construction sites. Algorithms and final formulas for computational modeling of the simplest sources of dynamic load are developed using the method of vibroacoustic analogies. The dynamic properties of the simplest dynamic load sources were analyzed. A significant difference between the computational models of real and ideal dynamic load sources. The article presents research and development results intended for calculating the distribution of dynamic loads on elements of construction structures in industrial and civil engineering projects located in areas with high levels of transport vibrodynamic impacts. An important property of the proposed computational equivalent models of sources of dynamic impact on building structures is the possibility of computational verification of critical elements, points, or nodes of load-bearing structures of buildings and structures under dynamic overloads. The position of these critical elements, points, and nodes of load-bearing structures under dynamic loads can differ significantly from their position determined using static and quasistatic computational modeling methods.

Interpretable prediction of remanence in sintered NdFeB through machine learning strategy

The effects of composition on magnetic properties of sintered NdFeB are generally revealed by trial-and-error method, which is actually time-consuming and resource-intensive. It has been demonstrated that data-driven machine learning (ML) strategy has a great potential in accelerating processes of material research. In this study, accurate prediction of remanence in sintered NdFeB magnets has been achieved by a high-quality and few-shot dataset. We used a set of physical and chemical properties of element as inputs to build ML models based on element classification knowledge. Specifically, according to the position of elements, we divided them into three categories and then calculated the average properties of three positions separately. The strong generalization ability of best-performing ML model was further verified in nineteen unknown samples with only 0.724 % error. In addition, the symbolic regressor (SR) and SHapley Additive exPlanation (SHAP) algorithm were employed to explain the model results from physical perspective. In short, a high-efficiency and feasible ML strategy was developed for predicting remanence of sintered NdFeB magnets. We believe that this work will show great prospects in the composition design and performance screening of sintered NdFeB magnets.

ENGINEERING AND GEODESIC MONITORING OF DEFORMATIONS OF BUILDING STRUCTURES DAMAGED AS A RESULT OF MILITARY AGGRESSION

The problem of engineering and geodetic monitoring of damaged buildings as a result of Russian aggression is extremely relevant in today's environment. The importance of this issue for the construction industry is particularly high. The right approach to the engineering and geodetic monitoring of damaged buildings and structures will allow timely detection of deformation development and development of a stabilisation programme to help prevent future damage.There are many different methods for effective deformation monitoring, each with its own unique characteristics. Among them are standard methods such as geometric levelling and linear-angle measurements. Geometric levelling involves measuring the height differences between different points on an object, which allows you to accurately determine the change in the position of structural elements. Linear-angle measurements include measuring the lengths and angles between points, which helps to identify any changes in the geometry of the building.In addition to standard methods, automated observation methods are also actively used. These methods include the use of modern instruments and technologies that allow for continuous monitoring of deformations in real time. For example, automated total station surveys, GPS systems, laser scanners and other high-precision instruments allow data to be collected with high accuracy and speed.Automated monitoring significantly improves the efficiency and accuracy of observations of building deformations. The use of such systems allows for real-time data to be obtained, which is extremely important for timely response to any changes in the condition of facilities. This is particularly relevant in the context of post-war reconstruction, when the speed and accuracy of work are critical to ensuring the safety and stability of buildings.This article presents the results of engineering and geodetic monitoring of a residential complex on Zvirynetska Street. At this facility, geodetic works were carried out to measure the settlements and horizontal displacements of two sections.

Synthesis of maximally sparse conformal circular arc array with a required beam pattern by unitary matrix pencil method

This paper extends the unitary matrix pencil (UMP) method to synthesize maximally sparse conformal circular-arc array with a required beam pattern. Due to the nonlinearity between the circular-arc array pattern and its element pattern, Fourier transform preprocessing for the required beam pattern is introduced to achieve a mathematical expression, i.e., sum of a series of undamped complex exponentials, which is related to array element positions and their excitations. Then, the UMP method is used to determine the reduced number of elements and their position distributions. Moreover, the complex excitations of array elements are reconstructed by obtaining the least-square solution of an over-determined equation. A set of examples for synthesizing sparse conformal circular-arc arrays with different desired patterns and E-type patch element including the mutual coupling are conducted. Results show that the proposed UMP method can achieve a considerably lower pattern reconstruction error with a reduced number of elements than results in the literature, which demonstrates its effectiveness and robustness.

Position estimation of acoustic elements based on improved delay estimation algorithm

Array signal processing is extensively utilized in the field of underwater acoustics (UWA). The majority of existing array signal processing algorithms require precise array position information to optimize their functionality. However, the intricate nature of the UWA environment introduces challenges such as the influence of water flow, which may result in deviations from the predetermined array positions. Consequently, this can amplify errors in array processing algorithms. Therefore, a high-precision array positioning method is needed to estimate the actual position of the array. The effectiveness of current array localization algorithms employing delay differential matching depends significantly on the accuracy of delay estimation and the formulation of the ambiguity function. In response to these crucial factors, this paper presents an algorithm for estimating array element positions that leverages an improved approach to delay estimation. Firstly, we propose the ρ-PHAT algorithm enhanced by the artificial fish swarm algorithm (AFSA-PHAT), significantly improving delay estimation accuracy, particularly in low signal-to-noise ratio (SNR) conditions. Compared to the traditional ρ-PHAT algorithm, this approach achieves a 3 dB increase in precision and a reduction in the root-mean-square error (RMSE). Additionally, a novel method is introduced for constructing the ambiguity function, which focuses on minimizing the acoustic complexity to encompass only direct and surface-reflected sounds. This improvement makes it particularly suitable for hydrophone arrays deployed near the sea surface. Computer simulations and experimental results validate that the algorithm, incorporating the aforementioned improvements, achieves enhanced accuracy in position estimation, reduced RMSE, and increased robustness.