Proper Configuration Research Articles

Analysis of Influential Parameters in the Dynamic Loading and Stability of the Swing Drive in Hydraulic Excavators

The proper design and configuration of the swing drive mechanism of a hydraulic excavator are crucial to improve energy consumption and efficiency and ensure operational stability. This paper analyzes the influence of the relationship between the parameters of a hydraulic motor and a reducer, which form the integrated transmission of a swing drive, the dynamic characteristics of a hydraulic excavator on loading, and the dynamic stability of the drive. The analysis deals with an excavator model that has the same parameters of the kinematic chain members, the same parameters of the upper structure drive mechanisms, and two variants of the swing drive that, with different integrated transmission parameters, provide the upper structure with the identical number of revolutions and equal rotating moment. One swing drive variant possesses an integrated transmission with a hydraulic motor with a low specific flow and a reducer with a high transmission ratio, while the other drive variant has the opposite parameters. Understanding this relationship is essential for optimizing the design of excavators to achieve better performance and dynamic stability under varying operational conditions. As an example, this paper provides the analysis results regarding the influence of the relationship between the parameters of the integrated transmission hydraulic motor and reducer on the loading and dynamic stability of the swing drive in a tracked hydraulic excavator of 100,000 kg in mass and 4.4 m3 in loading bucket volume, as obtained from the developed dynamic mathematical models of the excavator using the MSC ADAMS program. The results indicate that the dynamic loads on the swing drive’s axial bearing are higher in the variant with a low-specific-flow motor and high transmission ratio reducer during the acceleration and deceleration phases. However, this configuration demonstrated better dynamic stability, with lower oscillation amplitudes and shorter damping times compared to the variant with a high-flow motor and low transmission ratio. Those findings provide valuable criteria for the optimal synthesis of swing drive mechanisms in large hydraulic excavators using multi-criteria optimization methods.

Simulation model to enhance Bragg reflector assisted GeSn SACM-SPAD performance for 1550 nm LIDAR applications in autonomous vehicles

A safe 3-D lidar sensor for autonomous vehicle creates a high demand on 1550 nm SPADs detectors. Due to the limitation of the energy band gab and absorption coefficient of Si and Ge, their photodetectors have low efficiency at the 1550 nm wavelength. Doping Ge with Sn reduces its bandgap and enables higher efficiency in this range while adding Bragg reflector represents a smart way to increase absorption area effective thickness. Here a simulation model for Ge(1-x)Snx SACM SPAD is proposed to work as a 1550 nm laser detector. Two Bragg reflectors are built using Si\\SiGe and Si\\SiGeSn layers. Results show a significant enhancement on detector optical properties. PDP reaches 38 % at room temperature and the increase in Pdp due to Bragg reflector reaches 66 %. Although DCR also increases, it can be handled with proper dead time configuration.

Issues of personal data protection when using cloud technologies

It is indicated that in today’s digital world, where the amount of stored and processed data is growing at a frantic pace, issues of personal data protection are becoming increasingly important. With the proliferation of cloud technologies that allow companies and individuals to store and process information on remote servers, a new spectrum of threats to data privacy and security is emerging. The article examines the issue of personal data protection when using cloud technologies, in particular, the need to integrate legal and technological aspects to ensure comprehensive protection. The impact of international regulatory acts, such as GDPR (General Data Protection Regulation) and CCPA (California Consumer Privacy Protection Act), on cloud data protection processes is analyzed. Particular attention is paid to problems arising from differences in the legal regimes of different countries, which complicate data management at the international level. The article examines in detail modern technical solutions, such as data encryption and multi­factor authentication, which are key elements in protecting confidential information. These technologies have been found to provide a high level of protection, but also have their vulnerabilities. Based on this, it is proposed to invest in the latest technologies, in particular quantum encryption and artificial intelligence, to improve the effectiveness of data protection. Practical cases of data leaks are separately considered, which emphasize the importance of proper configuration of security systems and regular monitoring. Analysis of the results of empirical research shows the need to adapt business processes to changes in the regulatory environment and introduce new technologies to reduce risks. Based on the received data, recommendations for organizations are formulated, which include reviewing data protection policies, investing in modern technologies and training employees. The conclusions of the article emphasize the need for a comprehensive approach to ensuring the protection of personal data in cloud environments. This involves taking into account both modern technologies and current legal requirements to ensure adequate data protection and minimize possible risks.

Maximizing thermal management of photovoltaic-thermal systems with proper configuration of porous fins and phase change materials

Effective thermal management is crucial to enhance the performance and longevity of photovoltaic-thermal (PVT) systems. Phase change materials (PCMs) offer a promising solution for absorbing excess heat from PV modules; however, their poor thermal conductivity limits their effectiveness. This work explores the incorporation of porous fins within PCMs to improve heat absorption and thermal regulation in PVT systems. A detailed mathematical model is developed to analyze the effects of varying fin porosity (0.85 to 0.95), fin thickness (7 to 21 mm), fin height (7 to 21 mm), and fin inclination (-15° to 30°) on PCM melting and PVT cooling performance. Results show that optimally configured porous fins significantly enhance PCM melting rates and heat extraction from PV cells. Incorporating optimal fins reduces peak PV temperatures by up to 5°C compared to PCM alone at irradiation rate of 1000 W/m2. Meanwhile, reducing the fin thickness from 21 to 7 mm accelerates the overall PCM melting rate by 14%. The cooling performance also shows a nonlinear increase with fin tilt angle, with maximum enhancement occurring at 15° downward tilt for the studied configuration. The optimized fin-enhanced PVT design achieves 3.1% higher electrical efficiency and 15% increase in thermal efficiency compared to conventional PCM-PVT systems without fins. Findings provide design guidance to harness porous fins for maximized PCM-based cooling of PVT systems.

Configuration optimization of PV array for stratospheric airship under nonuniform radiation condition

The nonuniform solar irradiation on the stratospheric airship surface leads to overlooked mismatch losses in photovoltaic (PV) array. Proper configuration for PV array is crucial but frequently neglected in airship energy system research. In this paper, a mathematical model coupled with the layout of PV array on airship surface, radiation model, electrical model and energy balance model is established. The deployment of PV pack based on the distribution characteristics of solar radiation on airships surface is analyzed. Three maximum power point tracking configurations for the PV array are investigated in detail. The results indicate that mounting PV pack in axial series on stratospheric airships leads to higher power output compared to parallel-connected deployment, PV packs on stratospheric airships exhibit significant output power differences along the circumferential direction and minor differences along the axial direction, the peak of daily maximum output difference ratio is merely 0.4 % between the PV array under the distributed maximum power point tracking (DMPPT) and the partial distributed global maximum point tracking (PDMPPT) configuration, and PDMPPT configuration needs much fewer module, it emerges as the optimal choice for stratospheric airship PV array. This investigation can provide references for the further PV array configuration optimization under nonuniform radiation condition.

Data-driven study/optimization of a solar power and cooling generation system in a transient operation mode and proposing a novel multi-turbine modification concept to reduce the sun's intermittent effect

This study explores the integration of solar energy via parabolic trough collectors (PTC) with the Goswami cycle, focusing on evaluating life cycle costs (LCC) and energy performance in both steady-state and transient conditions. A suitable system configuration of a single-turbine Goswami cycle is designed for integration with PTC. Then, in the system's steady-state, a parametric study is performed based on the change in the design components. Subsequently, a multi-objective optimization method using energy and lifetime cost objectives are defined to identify the best system performance. This optimization technique utilizes artificial neural network (ANN) and the grey wolf optimizer (GWO) algorithm. Accordingly, the transient performance of the system is investigated during its optimal operating point using the TRNSYS software. Suitable controllers are considered for regulating power production and cooling system. Annual transient performance graphs of the systems are obtained. Following these investigations, a novel multi-turbine system is proposed. This configuration aims to enhance system reliability and diminish the reliance on storage devices by optimizing performance. The proper configuration of the five-turbine system with the required controllers is also provided. Hence, the method of dividing the turbine into similar turbines with lower capacity is a new concept proposed in this study. In the optimal state, it is observed that for 100 kW of net power output, 161 kW of effective cooling load can be achieved. At this configuration, the system's LCC amounts to 2.91 M. Moreover, during transient operation, an average power of 90 kW is attainable with a cooling load of 120 kW. The findings indicate that modifying the system from single turbine to five-turbines incurs an additional cost of approximately 9.2 % and reduces power output by 6 %. However, this modification significantly mitigates the transient impact of solar fluctuations.

Improving Database Performance with SQL Server Optimization Techniques

Database performance is critical for ensuring efficient data management and retrieval, particularly in environments that utilize SQL Server. As the complexity and size of databases increase, performance optimization becomes essential for maintaining responsiveness and reliability. This paper examines a range of SQL Server optimization techniques that can significantly enhance database performance. Key strategies include effective indexing, which improves query execution speed; query optimization, which refines SQL statements for better efficiency; and proper database configuration, which ensures that SQL Server is tuned for optimal resource utilization. Additionally, we explore the importance of regular maintenance tasks such as updating statistics and monitoring performance metrics to identify bottlenecks. By employing these techniques, database administrators can minimize latency, reduce resource consumption, and enhance overall system performance. Furthermore, this paper highlights the significance of ongoing performance assessments to adapt to evolving application demands and data growth. Ultimately, implementing these optimization strategies not only boosts SQL Server performance but also contributes to improved user experiences and organizational productivity.

Analysis of 3D positioning error for multipath indoor VLC system

SummaryA comparative analysis of 3D positioning error for two different configurations using different layouts of visible light communication (VLC) systems is presented in this paper. The Received Signal Strength (RSS) has been implemented for indoor localization systems using Line‐of‐Sight (LoS) and diffused reflection signals. The room size for configuration‐1 is 5 m × 5 m × 3 m, and the distance between adjacent LEDs is 2.5 m, 2.00 m, and 1.5 m for cases‐1, case‐2, and case‐3, respectively, whereas the room size for configuration‐2 is 7 m × 7 m × 5 m, and the separation between the LEDs is 3.5 m, 3 m, and 2.5 m for their respective cases. Through investigation, it has been shown that when only LS signal is considered, the separation between LEDs may not be an issue because positioning error changes by a very small amount as the separation between LEDs changes. The results show that as the distance between adjacent LEDs decreases, the received signal strength for LoS and L‐R1 signals increases. However, positioning error and BER rise, while the bit rate falls. Furthermore, the positioning error Vs receiver plane height for all three cases in configuration‐1 is the same up to a height of 2.89 m, whereas the positioning error in configuration‐2 is the same up to 4.4 m for all cases. The positioning error for case‐1 decreases as the height in configuration‐1 exceeds 2.89 m. Similarly, after reaching a height of 4.4 m for case‐2, the positioning error in configuration‐2 decreases. The LoS positioning error versus semi angle of the LED as well as the FOV of the receiver has been simulated for different positions of the receiver in configuration‐1. The investigation shows that the minimum positioning error is achieved at and FOV equal to 66.660 for all the positions of the receiver in the room. Thus, before configuring a practical indoor VLC geometrical model, proper VLC configurations such as LED separation, FOV of the receiver, semi angle of LED, and receiver height should be chosen based on the room dimensions.

Effect of swirl injection parameters on cooling performance of vortex-cooled bipropellant thruster

The cooling performance of a 10N-class gaseous Propane/GOx bi-propellant thruster with vortex cooling was investigated in this experimental study. Injecting oxidizer with a vortex was proposed as a potential cooling method for a semi-thermoplastic constructed thruster and demonstrated as a promising integrated cooling method that can be fabricated using 3D printing technology. Compared to other cooling types, vortex cooling has low system complexity and can be 3D printed as a single solid piece along with a thruster, reducing design complexity, weight, and manufacturing time. The experimental testing examined various injection configurations and their associated parameters to determine the most optimal injection combination. The test collected a comprehensive amount of data to evaluate the cooling performance with respect to varying operational parameters: oxygen-to-fuel ratio, propellant mass flow rate, and injection configuration. The study found that the acrylic chamber operated safely with a proper injection configuration identified maintaining the temperature of the thruster chamber walls below 60 °C, lower than the melting point of the acrylic material, with no damage observed. It was found that the downstream swirl injection had more favourable vortex cooling performance than the upstream injection for the scale of the thruster considered in this study.

High diffraction efficiency complex amplitude modulation technique by using antiwave functions.

Complex amplitude modulation (CAM) is a single-step technique that codes the amplitude and phase of a diffracted optical field into a real function. Loading this function onto a phase-only spatial light modulator enables the reconstruction of 3D images. However, the obtained images have poor brightness because of the low diffraction efficiency. In this work, we show a novel solution, to the best of our knowledge, that overcomes this limitation. This is done by employing antiwave complex exponential functions, which modify the spectrum of the diffracted field. Proper configuration of these functions allows transferring energy across the diffraction spectrum to the informative diffraction order, which significantly improves the brightness of the reconstructed image. Simulations and experiments prove the efficiency of the proposed method.

Security Assessment in Software Defined Networks (SDN): Vulnerabilities, Challenges and Research Prospects

Conventional internet architecture facilitating users for different services and applications but facing number of challenges like network management, QoS management for network virtualization, IP multicasting, deployment of IPV6, crucial security measures, end to end connectivity, inter and inter domain routing. To meet the demand of these services due to rapid growth of technologies and traffic, an emerging network architecture termed as Software Defined Network (SDN) with programmable technology has brought unprecedented management to control networks. Due to separation of data, control and application planes software defined network provides cost effective, openness, centralized automation, programmable features as per users own demands and high resilience to network administrators. OpenFlow evolved as a first standard protocol for software defined network control and data planes communication to meet changing business requirements. Although, Software Defined Network brings enormous advancements in networks to support business applications but it is severely affected with cyber-attacks at data, control and application planes. Middle boxes plays a significant role to manage network effectiveness and provide adequate security control from external and internal security threats but require proper management and configuration otherwise it leads to devastating effect. The main contribution of this paper are: (1) It explores various potential security attacks at SDN layers and inconsistent policies, (2) It provides various security concerns in SDN planes and preventive measures against these prevailing attacks, (3) It discusses security threats challenges and research opportunities in software defined network keeping in view critical security controls like spam detector, IDS/IPS, Firewall and policy management. This article assists researchers to comprehend security concerns and state of the art development and challenges explored by scientific community in SDN.

Selection of induction motor stator and rotor slot number combination for optimal NVH

With the rise of vehicle electrification, considerable research has been directed towards reducing motor noise, predominantly focusing on Permanent Magnet Synchronous Motors (PMSM). Despite the increasing popularity of the induction motor, driven by its reliability, cost-effectiveness, and lower environmental impact, discussions surrounding the Noise, Vibration, and Harshness (NVH) aspects of induction motors remain limited. This paper addresses the NVH implications associated with stator and rotor slot combinations in conventional squirrel-cage induction motors. Through a design parametric study that examines the impact of varying the number of rotor bars through analytical simulation, the findings not only identify the optimal slot combination for minimizing motor noise but also demonstrate the critical importance of selecting the proper slot configuration, as NVH performance can exhibit significant variations. A physical test was conducted to validate the analytical simulations. This research contributes valuable insights into the induction motor design, especially at the early design stage, emphasizing the necessity of considerations in achieving enhanced NVH performance.

Numerical simulations of the heavy rain event in the Democratic People's Republic of Korea during 9–10 August 2020

Accurate forecasting of heavy rainfalls and understanding of their dynamics are important to minimize the damage caused by them in the Democratic People's Republic of Korea (DPR Korea). This study is conducted on a heavy rainfall event (452 mm) on 9–10 August 2020 over Pankyo region located on the midlands of the Korean peninsula. To verify the proper configuration of convection-permitting simulations, sensitivity experiments were performed with five microphysical schemes (Lin, Goddard, Thompson, Morrison and WDM6) of the Weather Research and Forecasting (WRF) model. The results suggested that all high-resolution simulations reflect the main characteristics of observed precipitation pattern well, but the location and intensity of maximum precipitation from scheme to scheme. Among the considered all the microphysics, the Lin scheme showed the best agreement with observed precipitation. Results also showed that the Lin scheme reproduced the vertical distribution and time variation of several hydrometeors, as well as dynamic and thermodynamic parameters associated with heavy rainfall well. These outcomes suggest that the suitable selection of microphysics schemes with WRF model is important to predict and understand heavy rainfall events over the DPR Korea.

Evaluation of various FRP strengthening configurations for RC beam-column joints

There are several methods for strengthening reinforced concrete joints. Due to the unique properties of FRP (Fiber Reinforced Polymer) composites, the use of FRP laminates is one of the most commonly used techniques. The high cost of preparing concrete surfaces and attaching FRP laminates is a restricting factor for its application in reinforced concrete joint retrofit. Therefore, determining proper configurations that reduce the needed FRP material, as well as the surface preparation required for attaching FRP is an important factor in decreasing the strengthening cost. The proper arrangements of FRP strips can improve their performance in the rehabilitation and retrofit of reinforced concrete joints. To determine the proper configuration of FRP strips, finite element modeling was employed. The connection specimens are modeled in ABAQUS general-purpose finite element software and are classified into 10 general groups. To improve the performance of FRP strip configuration, the determined arrangement is investigated for different thicknesses and different widths of the FRP strips, and their results are compared with those of the connection specimen strengthened with full FRP coverage. The analysis results indicated that the load-bearing capacity of the connection retrofitted by the combined configuration of X-shape and orthogonal strips of FRP is close to that of the specimen with full FRP coverage. In this suitable configuration, the required FRP strips are reduced by about 30%, which decreases the cost and construction works needed for concrete joint rehabilitation.

Development of improved spray system with effective electrical electrodes for aerosol removal: An experimental study in UTARTS facility

Safe reactor decommissioning, especially for damaged Fukushima Daiichi (1F) nuclear power plants, is vital for environmental safety. Key challenges include remotely cleaning radiation hotspots and cutting fuel debris within the damaged primary containment vessel. However, submicron radioactive Aerosol Particles (APs) can be generated, thus necessitating effective aerosol control and removal to avoid radioactive environmental pollution and reduce radiation exposure risks during 1F decommissioning. Flue gases containing submicron APs that result in environmental pollution can also generated from other industrial works, e.g., coal, mining and chemical sectors. Conventional water spray is difficult to scavenge these small APs. Although previous studies showed the effectiveness of charged droplets on accelerating aerosol removal, the charging configuration is also important to scavenging performance. Hence, this study performs aerosol scavenging experiments in our UTARTS facility with varying induction electrode designs. Experimental results show the saturation of scavenging efficiency at high voltage and indicate the importance of charging polarity. Moreover, proper configurations of electrode position, geometry and material are studied and discussed. Our findings can be beneficial for the improvement of spray system for aerosol removal to mitigate radioactivity release and minimize contaminated water production and have implications for gas purification in various environmental and chemical industries.

ANALISIS EFISIENSI DAN KEAMANAN KONFIGURASI WEB PROXY DALAM MENGELOLA TRAFIK INTERNET DI LINGKUNGAN PENDIDIKAN

Internet use in educational settings is increasing, but can cause problems such as access to inappropriate content, the spread of malware, and misuse of bandwidth. Web proxies can be a solution for managing internet traffic efficiently and safely. This article analyzes the efficiency and security of web proxy configurations in managing internet traffic in educational environments. The efficiency of web proxy configuration is influenced by the type of web proxy, cache configuration, and bandwidth configuration. The security of a web proxy configuration is affected by authentication, content filtration, and software updates. Proper web proxy configuration can increase the efficiency and security of internet access for users in educational environments.

Coupling field optimization to improve the thermal transport of Gr/h-BN heterostructure

We perform a numerical evaluation on the multi-physical field coupling effect to improve the interfacial thermal conductivity (ITC) of Gr/h-BN (Graphene/Hexagonal boron nitride) planar heterostructure. The model of Gr/h-BN planar heterostructure (C-BN bonded configuration) is built to investigate the effect of the multifactor coupling effect of different temperatures, N-doping concentration, and single vacancy concentration on the ITC. Finally, the Box-Behnken orthogonal model is established to determine the optimal value of ITC under the coupling effect of multi-physical fields by response surface analysis, and the optimal value of ITC is 14.456 GW m−2 K−1 when the temperature is 673 K, the single vacancy is 2.57 %, and the N-doping is 18.9 %. It implies that the proper coupling configuration is found effective in improving the interfacial thermal conductivity of the Gr/h-BN heterostructure. This work is hoped to help promote the thermal reliability design of graphene heterogeneous interface for related micro/nano semiconductor devices.

Solution to the cocktail party problem: A time-reversal active metasurface for multipoint focusing

The cocktail party effect is the capability to focus one’s auditory attention on particular audio sources while ignoring other audio sources. We propose an experimental strategy to reproduce this ability by designing a time-dependent metasurface composed of independent active mirrors. Each active mirror is a programmable acoustic unit cell capable of hearing, computing, and re-emitting acoustic signals: each of them acts as a convolution filter. The proper configuration of the metasurface temporal filters allows one to establish an acoustic communication link between groups of individuals immersed in the noisy environment: a multiple-user multiple-input, multiple-output acoustic system is built. Published by the American Physical Society 2024

Influence of convective parameterization on the simulation of tropical cyclones over the South West Indian Ocean: A case study of tropical cyclone Idai (2019)

Proper configuration of the physical parameterization scheme is important for accurate outcomes of mesoscale weather forecasting model. This study evaluates the performance of four distinct cumulus parameterization schemes: the Kain-Fritsch (KF), Grell 3D ensemble (GR3D), Modified Tiedtke (MTIEDKE) and Modified Kain-Fritsch (MKF) schemes, in simulating Tropical Cyclone (TC) Idai (2019) in the Southern Indian Ocean. Utilizing the Weather Research Forecasting (WRF) model and TC best-track and satellite precipitation datasets, the research assesses the models' efficacy in replicating Idai's observed track and intensity. Results indicate that the KF, MTIEDKE, and MKF schemes reasonably capture Idai's southwestward track, with MKF demonstrating superior accuracy in reproducing observed intensity evolution. Conversely, the GR3D simulation exhibits a northwestward deviation, leading to notable track and intensity errors. Further investigations suggest that the smaller track and intensity differences in the MKF simulation are linked to the more accurate simulation of rainfall in both the surrounding environment and the TC inner-core region. The two factors exert strong influences on the large-scale steering flow and TC secondary circulation, respectively. The findings underscore the importance of selecting appropriate convective parameterization schemes for precise tropical cyclone simulations in the Southern Indian Ocean. This research contributes valuable insights into the intricate interaction between convective processes and atmospheric dynamics, offering implications for enhancing tropical cyclone prediction models in the region.

Uncrewed Vehicle Pathfinding Approach Based on Artificial Bee Colony Method

The presented study is dedicated to the dynamic pathfinding problem for UV. Since the automation of UV movement is an important area in many applied domains like robotics, the development of drones, autopilots, and self-learnable platforms, we propose and study a promising approach based on the algorithm of swarm AI. Given the 2D environment with multiple obstacles of rectangular shape, the task is to dynamically calculate a suboptimal path from the starting point to the target. The agent has been represented as UV in 2D space and should find the next optimal movement point from the current position only within a small neighborhood area. This area has been defined as a square region around the current agent’s position. The size of the region has been determined by the attainability of the agent's scanning sensors. If the obstacle is detected by the agent, the latter should be taken into consideration while calculating the next trajectory point. To perform these calculations, the ABC metaheuristic, one of the best representatives of swarm AI, has been used. The validation of the proposed approach has been performed on several 2D maps with different complexity and number of obstacles. Also, to obtain the proper configuration, an inverse problem of identification of guided function weights has been formulated and solved. The outlined results show the perspective of the proposed approach and can complement the existing solutions to the pathfinding problem.