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Optimizing Lithium-Ion Battery Thermal Management using CFD and Nano-Cooling
Get PDFThis study discusses the airflow for lithium-ion batteries during the charging process. The methodologies are designed for deployment on an inexpensive Battery Thermal Management System (BTMS). Hence, three separate phase model-based approaches for SOC estimation have been proposed and established, encompassing LIB modeling and identification techniques. This paper also examines the power intensity of a lithium-ion battery by combining and individual with the aforementioned methodologies to achieve better results. This research utilizes Computational Fluid Dynamics (CFD) to model and analyze fluid flow and heat transfer within lithium-ion batteries. It also explores the use of Phase Change Materials (PCMs) to enhance thermal management by regulating temperature through phase transitions. Together, CFD and PCMs aim to improve battery performance and safety. The best cooling efficiency was found to be achieved with a dielectric fluid, AL2O3 Nano fluid cooling system, and PCM nanofluid mixture. The battery reached 35 °C during the experimental cooling process and 34 °C during the simulation. The dielectric fluid with AL2O3 nano fluid cooling system and PCM reached a maximum temperature of 45 °C, while forced air and dielectric cooling reached maximums of 46 °C and 46 °C, respectively. The results are based on modern cooling efficiency techniques such as Phase Change Material (PCM) and Nano cooling fluids
Research on Damage Identification of Beam Structure Based on Dynamics
Get PDFIn this article, the damage identification methods based on structural modes are discussed. According to the curvature modes before and after damage, the traditional structural damage location method based on curvature change is improved, and based on the vibration differential equation of Euler-Bernoulli beam and Perturbation theory established a quantitative identification method for small structural damage. The cantilever aluminum beam model is established by ABAQUS, and different damage conditions are set up. The damage index method (D-index) and the curvature damage factor method (CDF) are used for localization analysis, and the perturbation theory is used to introduce the damage parameter ε for quantitative analysis. Taking the cantilever aluminum beam as the test object, the Piezoelectric Transducer-Scanning Laser Doppler Vibrometer (PZT-SLDV) modal test system is used to conduct vibration tests to verify the rationality and applicability of the methods, discuss the damage location, damage relationship between parameters. The research shows that the damage location can be accurately identified by the damage index method and the damage factor method, and the small damage severity can be effectively quantified by the damage parameter
Research on Key Technology Algorithms of Communication Network Intrusion Detection and Data Encryption Based on Artificial Intelligence
Get PDFIn order to solve the problem of network intrusion detection and data encryption, artificial intelligence is introduced into communication network intrusion detection. Obtain the intrusion data of communication network and analyze the abnormal behavior of communication network: Firstly, the intrusion behavior data is processed based on artificial intelligence algorithm, and the number of network security vulnerabilities and network attacks is screened out. Secondly, an adaptive monitoring method is designed by using reinforcement learning agent to interact with the environment and constantly update the characteristics of the agent. The practical application shows that the method has higher detection stability than the traditional fixed detection method. Finally, on the basis of obtaining the data of communication network nodes by using artificial intelligence technology, the obtained data of communication network nodes is encrypted by using mixed-pool mapping method. The results of design comparison and test show that the proposed artificial intelligence-based network communication data encryption transmission method has higher efficiency, shorter response time and less abnormal node loss, which proves that the proposed method has better encryption transmission performance
TransUNet Image 3D Reconstruction with Hyperparameter Optimization
Get PDFAncient architecture is characterized by its complexity and exquisite structure, but most existing images are in 2D format. This study proposes a TransUNet-based 3D reconstruction method with hyperparameter optimization for depth prediction to enhance the effectiveness, accuracy, and efficiency of reconstructing ancient buildings from 2D images. The method employs Restricted Boltzmann Machine (RBM) for depth prediction and an optimized ant colony algorithm for network parameter optimization. Experiments demonstrate that the proposed method achieves an average F1 score of 96.8% in reconstructing ancient buildings, outperforming other algorithms in terms of processing time and efficiency. The results validate the superiority of the proposed algorithm in processing images of ancient architecture, improving measurement accuracy and reducing execution time. This study contributes to the digitization and preservation of cultural heritage
Research on the Dynamic Evolution Model of the Influence of Foreign Trade on Economic Resilience Level Based on Triangular Fuzzy Entropy
Get PDFAs an important indicator of economic development, the degree of opening to the outside world measures the dependence of a country or region on foreign trade and foreign capital, which plays an important role in promoting economic growth and adjusting economic structure. On the contrary, regions with high dependence on foreign capital can show strong economic resilience. In this paper, the optimal weights of indicators are determined by the combination of the entropy value method of objective weighting and the triangular fuzzy method of subjective weighting. A dynamic evolution model of comprehensive economic evaluation based on the combination weighting is established. By evaluating indicators of criterion layers such as sustainable development and economic structure, the principle of the square sum of deviations between one indicator and another indicator is adopted. The multi-attribute comprehensive evaluation value of each evaluation object is dispersed as much as possible, so as to reflect the difference of index comparison more clearly, and change the situation that the index difference is not obvious due to the average weight in the existing portfolio empowerment research. In addition, it also adopts the research methods of literature research, comparative research, normative analysis and empirical analysis, and analyzes the degree of openness to the outside world into the degree of import dependence, export dependence and foreign capital dependence, and empirically explores the influencing factors of economic resilience from the above three perspectives, The results show that the main and objective weights are 0.471 and 0.529. Through empirical analysis, it can be seen that export dependence and import dependence have a significant negative impact on regional economic resilience, while foreign capital dependence has a significant positive impact on regional economic resilience. In the post-financial crisis period, when economic fluctuations are severe, the positive impact of foreign capital dependence on economic resilience is significantly increased
Održiva epoksidacija nezasićenih masnih kiselina perkiselinskim mehanizmom s amberlitnom smolom kao katalizatorom
No full textThe growing global transition from non-renewable to renewable raw materials has spurred significant interest in sustainable alternatives. Nevertheless, the utilisation of amberlite resin for catalysing the production of epoxidised palm oil remains underexplored. This study investigates the effects of varying the molar ratio of formic acid to palm oil (0.5:1, 1:1, and 2:1) and different stirring speeds (150rpm, 250rpm, and 350rpm) on the resulting oxirane value. Findings indicate that a molar ratio of 1:1 between formic acid and palm oil results in a 62% oxirane value within 30min, surpassing the outcomes of other tested ratios. A stirring speed of 350rpm produced the highest oxirane value, at 68%, compared to stirring speeds of 250rpm and 150rpm. The experiment successfully optimised the 1:1 molar ratio of formic acid to palm oil and a stirring speed of 350rpm to increase epoxidation of palm oil. The Runge-Kutta Fourth Order method, in conjunction with genetic algorithm optimisation for numerical integration, was used to establish a mathematical model.Rastuća globalna tranzicija s neobnovljivih na obnovljive sirovine potaknula je značajan interes za održivim alternativama. Primjena amberlitne smole za kataliziranje proizvodnje epoksidiranog palminog ulja nedovoljno je istražena. Ova studija istražuje utjecaje promjene molarnog omjera mravlje kiseline i palminog ulja (0,5:1, 1:1 i 2:1) te različitih brzina miješanja (150, 250 i 350 okretaja u minuti) na rezultirajući udio oksirana. Nalazi pokazuju da molarni omjer 1:1 rezultira s 62% oksirana unutar 30minuta te nadmašuje rezultate drugih ispitanih omjera. Brzina miješanja od 350 okretaja u minuti proizvela je najviše oksirana (68%). Da bi se povećala epoksidacija palminog ulja provedena je optimizacija procesa. Optimizacija je provedena kombinirajući metodu Runge-Kutta četvrtog reda s genetičkim algoritmom
VRIJEDNOST INTERNE REVIZIJE U UNAPREĐENJU DOBROG UPRAVLJANJA U JAVNOJ UPRAVI: SLUČAJ ALBANIJE
No full textPublic institutions are under increasing pressure to be accountable and restore trust in governmental operations. The internal audit unit, a crucial component of public institutions, has stepped up, providing assurance, educational and advisory services to decision-makers and senior officials. This role is pivotal for sustaining and enhancing good governance in public administration. In the context of the expanding global role of internal audit in public institutions, this paper explores its value proposition in promoting good governance in Albanian public management. Our qualitative methodology, primarily based on interviews with public internal auditors in Albania, reveals that the absence of a conducive environment, frequent changes of decision-makers, and political resistance to change impede internal auditors from delivering their educational and advisory services. However, this should not deter us. Our findings suggest that efforts to disseminate, enhance the quality, and promote internal audit services in Albanian public administration will yield valuable insights that will significantly contribute to good governance.Javne institucije su pod sve većim pritiskom da budu odgovorne i vrate povjerenje u rad Vlade. Jedinica za unutarnju reviziju, ključna komponenta javnih institucija, ojačala je pružajući usluge osiguranja, obrazovne i savjetodavne usluge donositeljima odluka i višim dužnosnicima. Ova je uloga ključna za održavanje i jačanje dobrog upravljanja u javnoj upravi. U kontekstu rastuće globalne uloge interne revizije u javnim institucijama, ovaj rad istražuje njezinu vrijednost u promicanju dobrog upravljanja u albanskoj javnoj upravi. Naša kvalitativna metodologija, primarno temeljena na intervjuima s javnim internim revizorima u Albaniji, otkriva da nepostojanje poticajnog okruženja, česte promjene donositelja odluka i politički otpor promjenama sprječavaju interne revizore u pružanju obrazovnih i savjetodavnih usluga. Međutim, to nas ne treba obeshrabriti. Naši nalazi pokazuju da će napori za širenje, poboljšanje kvalitete i promicanje usluga unutarnje revizije u albanskoj javnoj upravi dati vrijedne uvide koji će značajno doprinijeti dobrom upravljanju