Tool For Design Of Systems Research Articles

Load profiles of residential off-grid solar systems on the Navajo Nation

Standalone off-grid electrical systems, no matter where they are deployed or for what user class, are designed based upon the load they are expected to serve. State-of-the-art computerized off-grid system design tools require the user to specify the expected load profile, that is, how the power consumption changes throughout the day. Often, this is at an hourly resolution, and some characterization of the distribution of power around the average values may be required. Specifying realistic and reasonable load profiles is a barrier to the appropriate design of standalone systems. This research extends previous studies on daily energy consumption of residential solar-powered off-grid systems on the Navajo Nation to provide hourly load profiles, statistical characteristics, and probabilistic models. The data analyzed come from 90 homes over a two-year period. K-means clustering is used to identify prototypical normalized load profiles when the data are grouped by year, season, weekday, and weekend. Eight parametric probability density functions are fit to the grouped data at an hourly resolution. Their fit to the data is evaluated using the Cramér-von Mises (CvM) statistic. The results show that the load profiles tend to be night-peaking and that Log Normal and Gumbel distributions can reasonably model variation in the data. The load profiles and probabilistic models can be used in off-grid design software and to synthesize load profiles for design and future research.

System-Level Dynamic Model of Redox Flow Batteries (RFBs) for Energy Losses Analysis

This paper presents a zero-dimensional dynamic model of redox flow batteries (RFBs) for the system-level analysis of energy loss. The model is used to simulate multi-cell systems considering the effect of design and operational parameters on energy loss and overall performance. The effect and contribution of stack losses (e.g., overpotential and crossover losses) and system losses (e.g., shunt currents and pumps) to total energy loss are examined. The model is tested by using literature data from a vanadium RFB energy storage. The results show that four parameters mainly affect RFB system performance: manifold diameter, stack current, cell standard potential, and internal resistance. A reduction in manifold diameter from 60 mm to 20 mm reduced shunt current loss by a factor of four without significantly increasing pumping loss, thus boosting round-trip efficiency (RTE) by 10%. The increase in stack current at a low flow rate increases power, while the cell standard potential and internal resistance play a crucial role in influencing both power and energy output. In summary, the modeling activities enabled the understanding of critical aspects of RFB systems, thereby serving as tools for system design and operation awareness.

Towards a transformation approach from SecureUML to ‎Alloy

In critical information systems, Role-Based Access Control (RBAC) has been frequently used. The specification of access control policies is an essential step in securing information systems. This article presents a transformative approach for addressing design challenges within these specifications using Model-Driven Architecture (MDA). A method is introduced for specifying and verifying model-based access control (RBAC) rules by combining SecureUML and Alloy, referred to as SecureUML2Alloy. This approach leverages transformation techniques based on metamodels to express the SecureUML source model in the Alloy target model. The SecureUML2Alloy framework allows for the generation of an initial Alloy code that can be extended with facts, functions, and predicates depending on the case. The transformative framework offers a reliable, automated mechanism for verifying security specifications in critical systems, promoting both theoretical and practical advancements in model transformation and formal verification. This method provides a pathway for future automation tools in secure system design and analysis, contributing to the reliability and security of software systems across multiple fields.

The Mueller pupils Reduction-Zernike polynomial decomposition and polarization design criteria for the astronomical telescope system

This study introduces a novel method for decomposing polarization aberrations. It uses two sets of reduction matrices to decompose the diattenuation and retardance Mueller matrix into five independent reduction coefficients. And then, it uses Zernike polynomials to decompose these coefficients at the exit pupil, thereby providing a method for quantitatively analyzing the polarization aberrations. This method also gives the constraint values of the Zernike term of polarization aberrations during astronomical telescope design. Finally, the effectiveness and correctness of the process are verified by simulation of the actual optical system, pointing out that the D1, D2, D3, and R5 terms need to be calibrated and optimized to ensure polarization accuracy. This method offers a valuable tool and theoretical guidance for the polarization design of high-precision optical systems.

DESIGN OF WEB-BASED ACADEMIC SERVICE SATISFACTION INFORMATION SYSTEM OF WEST SUMATERA SHIPPING POLYTECHNIC

The design of a web-based information system for academic service satisfaction at the West Sumatra Shipping Polytechnic aims to overcome the problems of the survey system which is still manual. This can slow down the process of information at the West Sumatra Shipping Polytechnic. The system design in this Final Project (TA) was built using a website platform and run online. The research method uses the System Development Life Cycle (SDLC) with the Waterfall model approach which consists of 5 stages, namely, a) Analysis b) Design c) Implementation d) Maintenance e) Planing. The programming language used is PHP, and the database application uses the MySql data processor as the database. The system design tool uses the unified Modeling Language (UML) method using 5 (five) diagrams according to design needs, namely Usecase Diagrams, Activity Diagrams, Sequence Diagrams, Class Diagram and database design. This final project produces an effective and efficient Web-based design of an information system for academic service satisfaction at the West Sumatra Shipping Polytechnic that produces accurate and timely survey resultss

WEB-BASED MATHEMATICS LEARNING APPLICATION AT SMPN 9 KOTO XI TARUSAN

The web-based mathematics learning application at SMPN 9 Koto XI Tarusan aims to make the teaching and learning process more effective and efficient so that the time required is less than the conventional teaching and learning process. The data collection methods used are primary and secondary data, the system development method used is SDLC with UML (Unified Modeling Language) system design tools and uses a computerized system using black techniques. This learning application produces output in the form of information on student learning outcomes accurately and in a timely manner. This learning application apart from producing an effective and efficient teaching and learning process also produces more interesting learning information, namely by having a learning method using multimedia learning media compared to conventional learning.

WEB-BASED ONLINE FINAL ASSIGNMENT GUIDANCE INFORMATION SYSTEM IN DIII INFORMATICS MANAGEMENT PROGRAM, EKASAKTI UNIVERSITY, PADANG

The design of this system aims to design an effective and efficient WEB-based Online Final Assignment guidance information system for the Department of Informatics Management and can produce WEB-based Online Final Assignment guidance that can be applied in DIII Information Management at Ekasakti University, Padang. System design in this Final Project (TA) was built using a website platform that runs online. The system development method uses the System Development Life Cycle (SDLC) Waterfall which consists of 5 stages, namely, Analysis, Design, Implementation, Testing Maintenance,. The programming language used is PHP with MariaDb database. System design tools use the Unified Modeling Language (UML) method, namely UseCase Diagrams, Activity Diagrams, Sequence Diagrams, and Class Diagrams. This final project resulted in the design of an Online Final Assignment guidance information system based on the Informatics Management Department's WEB which can assist in improving guidance services that provide convenience quickly and accurately. The design of Web-based applications in the Informatics Management DIII program is expected to help and facilitate students and supervisors in the guidance process in the Informatics Management DIII major more quickly

WEB-BASED TOURISM INFORMATION SYSTEM IN BUNGUS TELUK KABUNG SUB-DISTRICT OFFICE

This system design aims to develop a web-based tourism information system for Bungus Teluk Kabung sub-district office and create applications that can be implemented in this sub-district office. This system research method is built on a website platform and runs online. The research method uses the system development life cycle (SDLC) with the waterfall model approach, which consists of 5 phases, namely: a) Analysis b) Design c) Implementation d) Maintenance e) Planning. The programming language used is (PHP), and the database application uses a data processor (MySql) as the database (RDBMS). The system design tools use Unified Modeling Language (UML) method with 4 (four) diagrams according to the design requirements, namely use case diagrams, activity diagrams, class diagrams and sequence diagrams. The tourism information application in the sub-district office of Bungus Teluk Kabung facilitates visitors to find information and tourist places in the study area. This system was tested and validated using the software testing method, using black box testing. This system can overcome the problems that exist in the area of Bungus Teluk Kabung sub-district.

Circular Systems Navigator: A Process Tool for Circular Systems Design and Rebound Effect Mitigation

Circular Systems Navigator: A Process Tool for Circular Systems Design and Rebound Effect Mitigation

Modelling of energy harvesting with bendable concrete and surface-mounted PVDF

Polyvinyl alcohol fiber reinforced engineered cementitious composite (ECC) using piezoelectric polymer film has attracted significant interest due to its energy harvesting potential. This work provides a theoretical model for evaluating the energy harvesting of bendable ECC using surface-mounted polyvinylidene fluoride (PVDF). In the mechanical part, concrete damage plasticity model based on the explicit dynamic analysis was utilized to simulate the dynamic flexural behavior of ECC beam under different dynamic loading rates. The mechanism of force transfer through the bond layer between the PVDF film and ECC specimen was simulated by a surface-surface sliding friction model wherein the PVDF film was simplified as shell element to reduce computational cost. Then, the electromechanical behavior of the piezoelectric film was simulated by a piezoelectric finite element model. A simplified model was also given for a quick calculation. The theoretical model was verified with the experimentally measured mechanical and electrical results from the literature. Finally, a parametric analysis of the effects of electromechanical parameters on the efficiency of energy harvesting was performed. The verified theoretical model can provide a useful tool for design and optimization of cementitious composite systems for energy harvesting application.

Internal temperature estimation for lithium-ion batteries through distributed equivalent circuit network model

Lithium-ion cells experience significant internal thermal gradients during operation, with a direct impact on their safety, performance, cost and lifetime. The estimation of the internal temperature of cells is therefore particularly important. In this work, a 3D distributed electro-thermal model for internal temperature estimation is developed for a cylindrical cell (LG M50T, NMC811). The model is parameterized and comprehensively validated against experimental data for 21700 cells, including direct core temperature measurements. Multiple types of electrical load are considered, including constant current discharge, pulse discharge, drive cycle and instant discharge/charge switching. The developed model is used to estimate core temperature based on surface temperature measurement. The predictions are shown to have good accuracy at relatively low computational cost. We show that the widely adopted two-node lumped thermal estimation model is increasingly inaccurate for more aggressive discharges, when thermal gradients become higher. Compared to the standard two-node model, the distributed equivalent circuit network model predicts the effects of detailed internal cell structure (electrode, current collector, metal can and tab) and distributed internal heat generation. The results are of immediate interest to cell manufacturers and battery pack designers, while the modelling and parameterization framework is a useful tool for energy storage systems design.

Sensitivity analysis of borehole thermal energy storage: examining key factors for system optimization

Borehole thermal energy storage (BTES) systems have garnered significant attention owing to their efficacy in storing thermal energy for heating and cooling applications. Accurate modeling is paramount for ensuring the precise design and operation of BTES systems. This study conducts a sensitivity analysis of BTES modeling by employing a comparative investigation of five distinct parameters on a wedge-shaped model, with implications extendable to a cylindrical configuration. The parameters examined included two design factors (well spacing and grout thermal conductivity), two operational variables (charging and discharging rates), and one geological attribute (soil thermal conductivity). Finite element simulations were carried out for the sensitivity analysis to evaluate the round-trip efficiency, both on a per-cycle basis and cumulatively over three years of operation, serving as performance metrics. The results showed varying degrees of sensitivity across different models to changes in these parameters. In particular, the round-trip efficiency exhibited a greater sensitivity to changes in spacing and volumetric flow rate. Furthermore, this study underscores the importance of considering the impact of the soil and grout-material thermal conductivities on the BTES-system performance over time. An optimized scenario is modelled and compared with the base case, over a comparative assessment based on a 10-year simulation. The analysis revealed that, at the end of the 10-year period, the optimized BTES model achieved a cycle efficiency of 83.4%. This sensitivity analysis provides valuable insights into the merits and constraints of diverse BTES modeling methodologies, aiding in the selection of appropriate modeling tools for BTES system design and operation.

Application of an active learning method for cumulative fatigue damage assessment of floating wind turbine mooring lines

Long-term cumulative fatigue damage of mooring lines is crucial for the design of floating wind turbine structures (FWTs). Although many efforts are carried out for the offshore floating platforms, there still needs to be an efficient approach for assessing the long-term fatigue damage of the floating wind turbine mooring lines due to the complex loading in FWTs. An active learning approach named AK-DA (Adaptive Kriging Damage Assessment) was recently proposed for the cumulative fatigue damage assessment of wind turbine structures. However, in the original work, the AK-DA approach was only tested on fatigue damage assessment of a 5MW wind turbine tower with monopile support structures. It is unclear whether it is applicable to other parts of the wind turbine system, especially considering the complex loading of FWTs. Therefore, in this work, the AK-DA approach is used to assess the cumulative fatigue damage of mooring lines. The Gaussian process regression (Kriging) model is used to predict the fatigue damage of the mooring line under different wind-wave cases. The cumulative fatigue damage of the mooring lines in the IEA 15MW semi-submersible wind turbines is assessed with the AK-DA approach. The numerical simulation results show that the AK-DA approach can efficiently and accurately estimate the cumulative fatigue damage of the mooring lines. Compared to the traditional simulation approach, the AK-DA approach can increase efficiency by more than 45 times, and the absolute error is less than 1%. This active learning approach could serve as a helpful tool for offshore mooring system designers, facilitating the cumulative fatigue damage assessment during the design process.

Method for Spatiotemporal Solar Power Profile Estimation for a Proposed U.S.–Caribbean–South America Super Grid under Hurricanes

Solar photovoltaic (PV) generation technology stands out as a scalable and cost-effective solution to enable the transition toward decarbonization. However, PV solar output, beyond the daily solar irradiance variability and unavailability during nights, is very sensitive to weather events like hurricanes. Hurricanes nucleate massive amounts of clouds around their centers, shading hundreds of kilometers in their path, reducing PV power output. This research proposes a spatiotemporal method, implemented in MATLAB R2023b coding, to estimate the shading effect of hurricanes over a wide distribution of PV solar plants connected to a high-voltage power infrastructure called the U.S.–Caribbean–South America super grid. The complete interconnection of the U.S., the Caribbean, and South America results in the lowest power valley levels, i.e., an overall percentual reduction in PV power output caused by hurricane shading. The simulations assess the impact of hurricanes in 10 synthetic trajectories spanning from Texas to Florida. The Caribbean would also experience lower power valleys with expanded interconnectivity schemes. The U.S.–Caribbean–South America super grid reduces Caribbean variability from 37.8% to 8.9% in the case study. The proposed spatiotemporal method for PV power profile estimation is a valuable tool for future solar power generation expansion, transmission planning, and system design considering the impact of hurricanes.

Agrivoltaic system design tools for managing trade-offs between energy production, crop productivity and water consumption

Agrivoltaic systems that locate crop production and photovoltaic energy generation on the same land have the potential to aid the transition to renewable energy by reducing the competition between food, habitat, and energy needs for land while reducing irrigation requirements. Experimental efforts to date have not adequately developed an understanding of the interaction among local climate, array design and crop selection sufficient to manage trade-offs in system design. This study simulates the energy production, crop productivity and water consumption impacts of agrivoltaic array design choices in arid and semi-arid environments in the Southwestern region of the United States. Using the Penman–Monteith evapotranspiration model, we predict agrivoltaics can reduce crop water consumption by 30%–40% of the array coverage level, depending on local climate. A crop model simulating productivity based on both light level and temperature identifies afternoon shading provided by agrivoltaic arrays as potentially beneficial for shade tolerant plants in hot, dry settings. At the locations considered, several designs and crop combinations exceed land equivalence ratio values of 2, indicating a doubling of the output per acre for the land resource. These results highlight key design axes for agrivoltaic systems and point to a decision support tool for their development.

Perancangan Aplikasi E-Learning Pada SMP Swasta Arridha Dengan Menggunakan Bahasa Pemograman PHP dan Database Mysql

This study elaborated on the design of E - Learning at Junior High School Arridha using the programming language PHP. From the research that has been conducted at Junior High School Arridha can be concluded that the system was not effective because the learning process is still done on the condition that the face to face between teachers and students . After doing some research on Junior High School Arridha , collecting data through interviews and other methods. Then the analysis of data collected by the system design tools . After the designed output design , design input , design files and E -learning . The results of the analysis have been carried out on the website of E -Learning in the PHP programming language , and the new system is expected to be able to provide facilities in the learning process in the First State School for more effective and efficient.

Parsing Data Log Hasil Pemblokiran Situs Negatif Di Satuan Kerja Perangkat Aceh

In today's digital age, internet access has become an integral part of everyday life, providing broad access to information and communication. However, these technological advances also bring negative impacts, including the potential for the spread of unwanted content or harm to society. The process of parsing negative site blocking datalog is a technique used to analyze and decipher log data resulting from site blocking activities. In this context, negative site blocking is not only focused on illegal content, but also involves efforts to mitigate cybersecurity threats, including phishing attacks, malware, and other malicious online activities. Use of Observation Methods (Observation), Interviews, Literature Studies where the author made direct observations at the Aceh Communication, Informatics and Coding Agency to find out about the negative site blocking datalog in the Aceh Equipment Work Unit, conducted direct interviews with Field Supervisors and staff at the agency to find out about the process of parsing negative site blocking datalogs at the Aceh Equipment Work Unit, collect and study references related to data parsing, negative site categories, websites, CodeIgniter 4 documentation, Bootstrap documentation, and information system design tools from various journals, theses, articles, and various other reference sources. The proposed system for parsing datalogs has clear functional and non-functional needs. Functional needs involve features such as login, blocking data management, category management, blocking graph representation and reporting. Meanwhile, non-functional needs include authentication security, responsive performance, and an intuitive user interface. Thus, parsing log data resulting from negative site blocking in the Aceh Device Work Unit is expected to provide significant benefits for Diskominsa Aceh in maintaining cyber security and morality in the use of the internet in its territory. These conclusions highlight the importance of implementing sophisticated technology solutions to understand, analyze, and manage block log data efficiently and effectively.
 

Modeling of flexible bevel gear rotor systems: Modal and dynamic characterization

Bevel gears, a crucial part of aircraft transmission systems, are more susceptible to wheel body vibration issues as lightweight requirements rise. In the past, the gear wheel body was often considered rigid while assessing the dynamic properties of gear systems. Constructing a bevel gear model with a thin-walled structure might not be appropriate for this modeling technique; this research suggests a dynamic model that considers the flexibility of bevel gears. The web and teeth structure of the gear are preserved by realistic modeling using three-dimensional hexahedral components. The component mode synthesis (CMS) approach reduces the model order for increased computational efficiency. To confirm the accuracy of the modeling method, the modal frequencies and vibration shapes of the proposed model single-gear shaft are compared with results from experiments and ABAQUS. By contrasting ABAQUS system-level meshing modal frequencies and vibration shapes, the accuracy of the system model assembly is further confirmed. The model examines the impact of bevel gear flexibility on the modal frequencies, modal vibration shapes, and system dynamic properties. The mode shape diagram at dangerous modal frequencies found using the modal strain energy technique and the vibration displacement cloud maps at resonance speeds computed using the Newmark-β method are mutually verified, and this demonstrates that lightweight bevel gears are more susceptible to excitation due to nodal diameter type vibrations. Proposed and traditional models anticipate substantially different resonance speeds since the traditional model assumes that the gear, being a rigid disk, can only excite the shaft's bending mode of vibration. The proposed model provides a more comprehensive description of the dynamic characteristics of bevel gear systems, providing a theoretical basis and optimization tool for the high-performance design, vibration reduction, and noise control of high-speed lightweight gear transmission systems.

Utilization of the Adams system for simulating collisions of wagons equipped with elastomeric buffers

The article introduces an innovative method for modeling elastomer buffers using a rheological structure. This approach entails a detailed mathematical description of buffer properties, seamlessly integrated into the ADAMS/Rail computer code for simulating impacts between two wagons. The simulation within ADAMS/Rail provides insights into the dynamic behavior of elastomer buffers during wagon impacts, considering forces, deformations, and overall responses. Serving as a valuable optimization tool for railway system design, this methodology contributes to improved safety and efficiency. The study’s comprehensive yet concise insights bridge the gap between theoretical modeling and practical application, enhancing our understanding of elastomer buffer dynamics and their pivotal role in railway operations.

DESIGN OF THRIFT SHOP E-CATALOG INFORMATION SYSTEM USING PHP AND JAVASCRIPT (CASE STUDY: MEYTWINS THRIFTING)

Currently, there is a popular trend among the younger generation regarding the use of used clothes. What's interesting is the emergence of the online thrift shop, which is a type of business that is booming in the fashion sector by selling used clothes through online platforms. Generally, these business people get clothing supplies in the form of bales (sacks) imported from abroad. The Online Thrift Shop has received a positive response from many young people by offering clothing that has a unique style in a retro or vintage atmosphere from the 90s, as well as world-famous brands. However, one of the obstacles faced by the online thrift shop is the mismatch between the products received by consumers and what was initially displayed by the seller. There are situations where the goods delivered to consumers do not match the description given by the seller. This phenomenon is one of the shortcomings that need to be considered in online thrift shop operations. There are many online shops that sell goods to consumers that do not match what is offered. This makes consumers' shopping confidence and comfort less comfortable. The aim of the research is to build an information system in the form of an e-catalog that can simplify the buyer process without having to come to the store, as well as provide information related to fashion products that are suitable for consumers or customers. In this research, we used the prototype method, then for the system design tools, we used UML modeling, and for database modeling, we used ERD. Information system built using PHP and Javascript. Then, based on the test results using BlackBox Testing from several respondents, the success rate of the system built was 95%.
 Keywords: E-Catalog, Prototype, PHP, Javascript, Blackbox Testing