Dimensions Of Components Research Articles

Wideband high-gain low-profile series-fed antenna integrated with optimized metamaterials for 5G millimeter wave applications.

This paper presents a series-fed four-dipole antenna with a broad bandwidth, high gain, and compact size for 5G millimeter wave (mm-wave) applications. The single dipole antenna provides a maximum gain of 6.2 dBi within its operational bandwidth, which ranges from 25.2 to 32.8GHz. The proposed approach to enhance both gain and bandwidth involves a series-fed antenna design. It comprises four dipoles with varying lengths, and a truncated ground plane. These dipoles are connected in series on both sides, running in parallel through a microstrip line. The proposed design significantly enhances the bandwidth, which extends from 26.5 to 40GHz. This frequency range effectively covers the 5G bands of 28 and 38GHz. The expedited trust-region (TR) gradient-based search algorithm is utilized to optimize the dimensions of the antenna components, resulting in a maximum gain of 11.2 dBi at 38GHz. To further enhance the gain, modified H-shaped metamaterial (MTM)-based unit cells are integrated into the antenna substrate. The TR algorithm is employed once more to optimize the MTM dimensions, yielding a maximum gain of 15.1 dBi at 38GHz. The developed system is experimentally validated, showing excellent agreement between the simulated and measured data.

Employer Brand: Experience dimensions, components, and appeals in a telecommunications company

This article examines the concept of employer branding through its dimensions of experience, components, and appeals. The research is based on a case study of a mobile telecommunications company (Tigo) with a focus on the experience centers in Barranquilla, Colombia. The study, with a descriptive scope, applied a quantitative survey technique to 107 employees in roles such as administrators, coordinators, and commercial advisors. The survey instrument was constructed through literature review, and measurement questions were identified through expert validation. The results indicate that employees perceive the dimensions of employer branding experience, components, and appeals positively. Although components of employer branding showed a lower average compared to other concepts, they remained positive for the company. These findings are relevant for understanding employer branding in customer interaction areas such as experience centers.

Possible origin for the similar phase transitions in k-core and interdependent networks

The models of k-core percolation and interdependent networks (IN) have been extensively studied in their respective fields. A recent study has revealed that they share several common critical exponents. However, several newly discovered exponents in IN have not been explored in k-core percolation, and the origin of the similarity still remains unclear. Thus, in this paper, by considering k-core percolation on random networks, we first verify that the two newly discovered exponents (fractal fluctuation dimension, , and correlation length exponent, ) observed in d-dimensional IN spatial networks also exist with the same values in k-core percolation. That is, the fractality of the k-core giant component fluctuations is manifested by a fractal fluctuation dimension, , within a correlation size Nʹ that scales as , with . Here we define, and . This implies that both models, IN and k-core, feature the same scaling behaviors with the same critical exponents, further reinforcing the similarity between the two models. Furthermore, we suggest that these two models are similar since both have two types of interactions: short-range (SR) connectivity links and long-range (LR) influences. In IN the LR are the influences of dependency links while in k-core we find here that for k = 1 and k = 2 the influences are SR and in contrast for the influence is LR. In addition, analytical arguments for a universal hyper-scaling relation for the fractal fluctuation dimension of the k-core giant component and for IN as well as for any mixed-order transition are established. Our analysis enhances the comprehension of k-core percolation and supports the generalization of the concept of fractal fluctuations in mixed-order phase transitions.

基于机器视觉的马铃薯幼苗破膜装置设计与试验

An automatic potato seedling film-breaking device based on machine vision was designed to reduce the labor intensity of potato film-breaking. The device mainly consists of a motion mechanism, a seedling recognition mechanism, a film-breaking mechanism, etc. Based on single-ridge and single-row potato planting agronomy, the whole structure and key component dimensions of the film-breaking device are determined, the YOLOv5s model is improved to build a potato seedling recognition system, and the film-breaking mechanism based on the parallel CoreXY structure is designed. Potato seedlings at the emerging stage are used as research objects for field film-breaking tests. The results show that the recognition rate of potato seedlings is 89.7%, the qualified rate of film-breaking is 83.5%, and the damage rate is 2.3%. This paper can provide technical support for the development of intelligent film-breaking equipment for potato seedlings.

Coffee Tourism Development Potential in Banyuwangi Regency, East Java

Cultural diversity and local wisdom become a promising attraction in advancing Indonesian tourism. Coffee Tourism is one of the tourist attractions that can offer a unique travel experience. The aim of this research is to know the potential and strategy of development of Coffee Tourism in Banyuwangi district, East Java. Using qualitative research methods, data processing is carried out through observations, interviews and documentation related to the potential and development strategies of Coffee Tourism in the region. Sample on this study was more focused on stakeholders related to coffee tourism, such as local governments, local tourism agencies, coffee farmers, coffee entrepreneurs, coffee-based micro business, and tourists. This study focuses on four dimensions of tourist attraction components: attractions, accessibility, amenities, and ancillary services. The study's findings indicate that Banyuwangi Regency's tourism attraction component has sufficient potential as a coffee tourism. The four tourist attraction components in the Banyuwangi district have generally met the requirements for the development of coffee tourism, despite some remaining flaws. Because of Banyuwangi's distinct cultural advantages, coffee tourism in this region can be intriguing and promising

Optimization Of CIPP Evaluation Model as An Escalation of Educational-Industrial Collaboration Program

The importance of industrial and vocational collaboration in producing competent graduates is evident. However, there are still issues with the collaboration between industry and educational institutions, including the lack of appropriateness in the collaboration, the mismatch between student competencies in vocations and industry requirements, and inadequate alignment of graduate outcomes with industry needs. This research aims to explore the differing perspectives of universities, vocational schools, and industries in West Sumatra, Bandung, and Malang on the formation of CIPP components. Additionally, it seeks to reveal the direct and indirect influences between CIPP components—context, input, process, and product—to enhance the quality of cooperation and collaboration between industry and universities in Indonesia. The research employs a mixed-method approach, combining quantitative and qualitative methods. The samples include vocational schools, involving teachers and leaders, and universities, involving lecturers and leaders in West Sumatra, Bandung, and Malang. The research instruments consist of a questionnaire and an interview guide. Both qualitative and quantitative data analysis techniques are applied, including descriptive analysis, difference tests using two-way ANOVA, and factor analysis tests using the SMART PLS application. Based on the findings, it is concluded that the evaluation results encompass the Context, Input, Process, Product (CIPP) variables in an ideal vocational school-university-industry collaboration model. The results indicate a direct and indirect positive influence between CIPP components. However, the evaluation results also highlight existing problems, necessitating improvements. This research contributes by providing recommendations for the collaboration program to enhance input capacity and generate relevant outcomes. In terms of input, the value is classified as very good, emphasizing the need for improvement in the dimensions of the context components, especially the competency environment, stakeholders, and policies that support optimal cooperation. Recommendations in the product section aim to increase student competency achievement.

Design of Rectangular Patch Microstrip Antenna with Defected Ground Structure Method at 3.5 GHz Frequency for 5G Technology

5G technology is currently developing rapidly in various countries. 5G technology has three sub-frequencies: low band, midband and high band. Midband frequencies in Indonesia are between 2.6 GHz and 3.5 GHz. In order for 5G technology is able to be used in Indonesia, it needs an antenna that can work at 3.5 GHz and has a wide bandwidth. Microstrip antenna is a simple and efficient antenna. However, microstrip antenna has minimal bandwidth. To overcome this, certain methods are needed, one of which is the defected ground structure (DGS) method. The initial design of the antenna has dimensions according to the results of the calculation formula. Then optimization is carried out by reducing the dimensions of the antenna components. After that, the DGS method is applied to widen the bandwidth. The initial design of the single-patch antenna before using the DGS method has a return loss value of -19.96 dB, VSWR 1.22, with a gain value of 3.812 dB and bandwidth 105.1 MHz. The simulation results of the antenna using DGS have a return loss value of -39.76 dB, VSWR of 1.02, with a gain value 3.16 dB and a bandwidth of 158.4 MHz. These results prove that the use of the DGS method can increase bandwidth.

RF fingerprint extraction and device recognition algorithm based on multi-scale fractal features and APWOA-LSSVM

RF fingerprints can be used for device identification and network access authentication. An RF fingerprint extraction and device identification algorithm based on multi-scale fractal features and APWOA-LSSVM is proposed. First, a Hilbert transform is performed on the original RF signal, and differential operations are performed on the I/Q signal. Then, the variational modal decomposition is performed on the differentially processed I/Q signals separately to obtain a number of band-limited Intrinsic Modal Function (IMF) components. The fractal box dimension of each IMF component is calculated separately as the first-dimensional RF fingerprint. The multi-fractal spectrum of the original RF signal is further computed by Multi-fractal Detrended Fluctuation Analysis (MFDFA) as the second-dimensional RF fingerprint. The RF fingerprint feature vector consists of a combination of the first- and second-dimensional RF fingerprints and is used to train the LSSVM model. Since the penalty factor and kernel parameter width directly affect the recognition accuracy and generalization ability of the LSSVM model, APWOA is used to optimize the hyperparameters of the LSSVM model. Finally, the LSSVM model is constructed using the optimal hyperparameters and the performance of the model is verified on a test dataset. The experimental results show that the proposed model achieves an average recognition accuracy of 99.13%\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\%$$\\end{document} for 16 Bluetooth devices. Multi-scale fractal features consisting of fractal box dimensions and multiple fractal dimensions are more beneficial in the recognition of wireless devices as compared to single features. In addition, the proposed model possesses superior recognition capabilities when compared to classical machine learning algorithms.

Techno-economic analysis and optimal sizing of hybrid PV-wind systems for hydrogen production by PEM electrolysis in California and Northern Germany

The aim of this study is to assess the economic potentials of power and hydrogen generation via solar and wind energy resources at locations in Northern Germany and California, both of these (geographical) regions being pioneers in terms of a sustainable energy transition. Based on extensive research and electrolyzer manufacturer interviews, green hydrogen generation plants are modeled in a MATLAB® environment. All relevant inputs and outputs of the systems studied (wind power plants, photovoltaic power plants, and polymer electrolyte membrane electrolyzers, among others) are considered for different locations and framework conditions. In contrast to the existing literature, special attention is paid to the part-load behavior of electrolysis systems, which becomes particularly relevant in their interplay with volatile renewables. Metrics such as the levelized costs of electricity (LCOE) of the wind and photovoltaic power plants and the resulting levelized costs of hydrogen (LCOHy) are determined. With the help of the developed model, dimensioning of a whole system's components can be determined for different locations. A case study is conducted for a Northern German site and another one for a site in the Californian Mojave Desert. Both the optimal dimensioning of the renewable energy plants and the ratio of installed wind and photovoltaic power plant capacity are strongly location-dependent. In Northern Germany, for example, lower LCOHy can be generated at higher wind power plant capacity shares and, in the Mojave Desert, be produced at higher photovoltaic power plant capacity shares. In general, with larger plants and correspondingly larger polymer electrolyte membrane electrolyzers, LCOHy are lower due to scaling effects. Following this dimensioning recommendation, the LCOHy vary between 4.5 €/kg and 5.2 €/kg in the Northern German case study and between 4.6 US$/kg and 5.3 US$/kg in the Californian one. With costs of 1–2 €/kg, gray hydrogen is still economically superior.

International comparison and insights on sustainable competitiveness of water industry management models: evidences from France and China.

The sustainability of water industry management model is one of the essential means to achieve sustainable utilization of water resources. Based on existing research on the sustainability of water industry, this study explores the factors affecting the sustainable competitiveness of water industry management model. It constructs a more complete sustainable competitiveness evaluation indicator system. Evidences taken from France and China were selected as the references for the study, and the principal component analysis was used to evaluate the overall sustainable competitiveness and main component dimensions. It is found through this study that the overall competitiveness indicator in the sustainable water industry management model and the sub-dimensional competitiveness indicators in resource support, development base, and environmental impact of water industry of France are better than those of China. China is more competitive in social inclusion, technological innovation, and sustainability of water industry. Based on the research results, this study provides insights into solving the existing issues in the sustainable development of China's water industry to support how China can adjust its water industry management model to improve its sustainable competitiveness.

Monitoring the forming dimensions of components produced by arc-directed energy deposition based on a molten pool’s geometric characteristics

Monitoring the forming dimensions of components produced by arc-directed energy deposition based on a molten pool’s geometric characteristics

Numerical simulation of transient boiling and void cross flow in non-uniformly heated 5 × 5 rod bundle

A multi-dimensional numerical simulation has been conducted for a transient boiling experiment by applying rapid and non-uniform power to fluid in a 5×5 bundle channel simulated a BWR fuel assembly in atmospheric pressure. The experiment is to investigate thermal hydraulic behavior in applying transient power to subcooled reactor coolant in a stand-by mode of a nuclear power plant such as reactivity initiated accident (RIA). The numerical simulation has been conducted by TRACE (version 5.0 / patch 5) which is a nuclear system analysis code to solve thermal hydraulics of boiling two phase flow by a two fluid model. The bundle channel in the upward vertical direction has been simulated by a three dimensional component with the Cartesian coordinate system attaching heat structures to simulate heating rods for thermal conduction and heat transfer calculation. It has been revealed that the numerical result is possible to simulate the void cross flow through the sub-channel in the bundle channel qualitatively as observed in the experiment. However, there was room for improvement for a wall heat transfer model in TRACE because the numerical result is larger than the experimental result in terms of the rising rate of the rod temperature during the rapid initial increasing of applied power, and it has been inferred that the evaluation model for an onset of nucleate boiling in TRACE also has to be improved because the void initiation time in the numerical result was earlier than the experimental result. Therefore, TRACE has been optimized by modifying the two physical models described above. The numerical results with the modified TRACE have been in better agreement with the experimental results than those with the original TRACE. Using the modified TRACE, a numerical experiment has been conducted putting an inlet velocity and subcooling of fluid and applied power as parameters in addition to the experimental conditions. The results have shown that there is a square law correlation between a void cross flow and applied power to the fluid. The experiments and analyses in this study have elucidated the behavior of transient boiling two phase flow in a fuel assembly of a nuclear power plant at the transient event such as RIA.

The Pedicled Sensate Osteocutaneous Groin Flap for Reconstruction of the Forearm and Hand

Background The groin flap is axial pedicled and versatile. Until now, this flap has been used with many modifications for the reconstruction of forearm and hand defects. However, this flap has not been used in forearm, hand, and thumb reconstruction as a pedicled sensate osteocutaneous flap. In this study, a pedicled sensate osteocutaneous groin flap was used for the reconstruction of composite tissue defects on the forearm, hand, and thumb. Patients and Methods A pedicled sensate osteocutaneous groin flap was used to reconstruction composite tissue defects on the forearm, hand, and thumb in 7 patients. The mean age of the patients was 42 years. The defects were located on the dorsal surface of the forearm and hand in 2 patients, the dorsal surface of the hand and finger in 2 patients, and the thumb in 3 patients. The dimensions of the flap skin paddle ranged from 7 × 11 cm to 8 × 23 cm, and the dimensions of the bone component ranged from 1 × 1.5 × 3.5 cm to 1 × 1.5 × 5 cm. The mean follow-up duration was 26 months. Results All the flaps survived. Flap debulking was performed using 3 flaps. Sensory recovery in the flaps was completed approximately 18 months after the first operation. When the results of static 2-point discrimination test and Semmes-Weinstein monofilament test were evaluated at 18 months postoperatively, it showed that protective sensation was obtained. Except for 1 patient, motion restriction did not develop in the wrist, elbow, or shoulder joints. An acceptable aesthetic result, minimal donor site deformity, and protective sensation were obtained in all patients. Conclusions The pedicled sensate osteocutaneous groin flap can be safely used in the reconstruction of forearm and hand composite tissue defects that do not have available vascular structures for free flaps in the recipient area and in thumb reconstruction where toe transfer and pollicization cannot be performed.

Graphical methods and rings of invariants on the symmetric algebra

Abstract Let G be a complex classical group, and let V be its defining representation (possibly plus a copy of the dual). A foundational problem in classical invariant theory is to write down generators and relations for the ring of G-invariant polynomial functions on the space $\mathcal P^m(V)$ of degree-m homogeneous polynomial functions on V. In this paper, we replace $\mathcal P^m(V)$ with the full polynomial algebra $\mathcal P(V)$ . As a result, the invariant ring is no longer finitely generated. Hence, instead of seeking generators, we aim to write down linear bases for bigraded components. Indeed, when G is of sufficiently high rank, we realize these bases as sets of graphs with prescribed number of vertices and edges. When the rank of G is small, there arise complicated linear dependencies among the graphs, but we remedy this setback via representation theory: in particular, we determine the dimension of an arbitrary component in terms of branching multiplicities from the general linear group to the symmetric group. We thereby obtain an expression for the bigraded Hilbert series of the ring of invariants on $\mathcal P(V)$ . We conclude with examples using our graphical notation, several of which recover classical results.

Ulrich bundles on some threefold scrolls over [formula omitted

We investigate the existence of Ulrich vector bundles on suitable 3-fold scrolls Xe over Hirzebruch surfaces Fe, for any e⩾0, which arise as tautological embeddings of projectivization of very-ample vector bundles on Fe that are uniform in the sense of Brosius and Aprodu–Brinzanescu, cf. [10] and [3] respectively.We explicitly describe components of moduli spaces of rank r⩾1 vector bundles which are Ulrich with respect to the tautological polarization on Xe and whose general point is a slope-stable, indecomposable vector bundle. We moreover determine the dimension of such components, proving also that they are generically smooth. As a direct consequence of these facts, we also compute the Ulrich complexity of any such Xe and give an effective proof of the fact that these Xe's turn out to be geometrically Ulrich wild.At last, the machinery developed for 3–fold scrolls Xe allows us to deduce Ulrichness results on rank r⩾1 vector bundles on Fe, for any e⩾0, with respect to a naturally associated (very ample) polarization.

Examining the Psychological Components of Academic Imposter and the Effectiveness of the Completed Program Based on the Dimensions of Academic Well-Being Components in Medical Students of Kurdistan

Examining the Psychological Components of Academic Imposter and the Effectiveness of the Completed Program Based on the Dimensions of Academic Well-Being Components in Medical Students of Kurdistan

Monitoring the evolution of dimensional accuracy and product properties in property-controlled forming processes

As recent trends in manufacturing engineering disciplines show a clear development in the sustainable as well as economically efficient design of forming processes, monitoring techniques have been gaining in relevance. In terms of monitoring of product properties, most processes are currently open-loop controlled, entailing that the microstructure evolution, which determines the final product properties, is not considered. However, a closed-loop control that can adjust and manipulate the process actuators according to the required product properties of the component will lead to a considerable increase in efficiency of the processes regarding resources and will decrease postproduction of the component. For most forming processes, one set of component dimensions will result in a certain set of product properties. However, to successfully establish closed-loop property controls for the processes, a systematic understanding of the reciprocity of the dimensions after forming and final product properties must be established. This work investigates the evolution of dimensional accuracy as well as product properties for a series of forming processes that utilize different degrees of freedom for process control.

USING THE METHOD OF CONFIRMATORY FACTOR ANALYSIS FOR THE SIMULATION OF TECHNICAL SYSTEMS

Problem statement. Analyzing the dynamics of the functioning of complex technical systems, which are characterized by a certain architecture and the interaction of system components, in most cases, there are certain difficulties associated with the description of system-wide issues. Among such issues, first of all, it is possible to include problems related to the direct mathematical formalization of the overall system structure, the organization of relationships between its elements, the interaction of system elements with its external environment, control of the activities of its elements, etc. In such cases, most often researchers use the procedure of mathematical modeling. At the same time, there is a fairly large range of phenomena, in the analysis of which it is possible to use the traditional apparatus of mathematical modeling. In such situations, it is possible to apply modeling techniques that represent the model in the form of an algorithmic program for an electronic computer, the so-called simulation modeling. The purpose of the article. Application of simulated physical and mathematical modeling by the method of confirmatory factor analysis for the study of complex technical processes. Conclusion . The relationship between the parameters of the laser welding mode and the morphological criteria of the structural state of low-carbon low-alloy steel 09Г2С was investigated using the mathematical apparatus of simulation modeling, namely confirmatory factor analysis. The confirmatory factor method was implemented in the form of a path diagram, namely a graphical interpretation of the relationship between the structural condition criteria and laser welding parameters. The percentage content and geometric dimensions of the main structural components of ferrite and pearlite were used as criteria for the morphology of the structural state, and the geometric dimensions of the welded joint sections were used as welding parameters. The adequacy of the obtained model was confirmed by constructing a probability plot of normalized residuals according to the quasi-Newtonian method of residuals.

Modelling and performance assessment of a two-bed adsorption chiller at different operating conditions

The study aims to assess the performance of an adsorption chiller using the Maxsorb III-methanol as an adsorbent pair. A modified transient lumped parameter model was developed to evaluate the dynamic behavior of the system at various operating parameters. Methanol is used as refrigerant as it has a significant latent heat of evaporation, high normal boiling point, low melting point and environmentally friendly. The results showed that the modified transient lumped parameter model can predict well the dynamic behavior of the adsorption chiller under different operating conditions. The system was able to produce about 13.65 kW (227 W kg-1) cooling capacity with a thermal COP of 0.73 at 85 and 30 oC driving source and cooling temperatures respectively. In addition, simulation tests were made to compare the performance of the Maxsorb III-methanol system with the different working pairs at the same physical dimensions of the present system components and operating parameters. At heat source temperatures of 85 oC which can be gained from waste heat or solar energy, the COP of the Maxsorb III-methanol cycle was about 12.0%, 44.0% and 6.6% higher than that of ACF-ethanol, silica-gel-water and activated charcoal/methanol cycles. The Maxsorb III/methanol adsorption cycle can work effectively with low grade heat sources, which can be gained from renewable energy or waste heat sources.

Modelling and performance assessment of a two-bed adsorption chiller at different operating conditions

The study aims to assess the performance of an adsorption chiller using the Maxsorb III-methanol as an adsorbent pair. A modified transient lumped parameter model was developed to evaluate the dynamic behavior of the system at various operating parameters. Methanol is used as refrigerant as it has a significant latent heat of evaporation, high normal boiling point, low melting point and environmentally friendly. The results showed that the modified transient lumped parameter model can predict well the dynamic behavior of the adsorption chiller under different operating conditions. The system was able to produce about 13.65 kW (227 W kg-1) cooling capacity with a thermal COP of 0.73 at 85 and 30 oC driving source and cooling temperatures respectively. In addition, simulation tests were made to compare the performance of the Maxsorb III-methanol system with the different working pairs at the same physical dimensions of the present system components and operating parameters. At heat source temperatures of 85 oC which can be gained from waste heat or solar energy, the COP of the Maxsorb III-methanol cycle was about 12.0%, 44.0% and 6.6% higher than that of ACF-ethanol, silica-gel-water and activated charcoal/methanol cycles. The Maxsorb III/methanol adsorption cycle can work effectively with low grade heat sources, which can be gained from renewable energy or waste heat sources.