MATTER: International Journal of Science and Technology

EFFECT OF DIFFERENT UV EXPOSURE ENERGY ON POLYIMIDE-BASED NONVOLATILE RESISTIVE PHOTOMEMORY DEVICE

Xin-Rong Wu, Pei-Ying Jiang, Syuan-Yi Li, Wen-Luh Yang — Sun, 15 Jun 2014 00:00:00 +0000

Recently, many researchers pay attractive attention to organic memory technology. Polyimide film was used as the resistive switching layer of nonvolatile photomemory in this study. In order to improve the performance of the device, different wavelengths of Ultraviolet (UV) light were used to operate the device, and its impact on the polyimide film was discussed. In this paper, three different UV light bands, UVA, UVB, and UVC, are used to switch devices between low resistance state (LRS) and high resistance state (HRS). It can be seen from the results that all three kinds of energies of UV light can transform the polyimide film from HRS to LRS successfully. According to the data, after 1s of UVB irradiation, the LRS current of polyimide-based photomemory device is the largest, and the data retention ability is also the best, the second is to irradiate UVA, and the last is to irradiate UVC. The results of the optical properties and electrical properties are coincidental. Therefore, different UV energies can affect this photomemory device.

SIMULATING MOLECULAR OPTICAL PROPERTIES OF POLYIMIDE FOR NONVOLATILE RESISTIVE PHOTOMEMORY DEVICES

Thu, 20 Jun 2024 00:00:00 +0000

In this study, the focus was on utilizing the polyimide (PI) thin film as a resistive conversion layer for organic polyimide-based resistive random-access memory (ReRAM) applications. We utilized the 3D molecular editor WebMO to manipulate and analyze the structures of Aromatic-PI and Quinoid-PI molecules. The molecular chain length, molecular weight, and HOMO/LUMO molecular orbitals were investigated to gain insights into the fundamental properties of PI molecular structures. The analysis revealed that the Quinoid-PI molecule exhibited a shorter molecular chain compared to Aromatic-PI, attributed to the inability of the cyclic structure in Quinoid-PI to maintain a planar conjugated structure, resulting in an uneven overall structure and reduced molecular chain length (Norcorss, 1988). The research results demonstrate that the optical energy gap of Aromatic-PI remains constant regardless of the number of molecular bonds, with a value of approximately 3.2661 eV. In contrast, for Quinoid-PI, the optical energy gap undergoes a significant decrease as the number of molecular bonds ranges from 1 to 5. As the bond count increases to 20~23, the change in the optical energy gap gradually diminishes, ultimately resulting in an optical energy gap of 0.6932 eV. This observation indicates that longer molecular chains composed of Aromatic-PI act as insulators, while Quinoid-PI transforms into a low-energy gap conductor.

CASALE MONFERRATO REMEDIATION: ASBESTOS POLLUTION AND SAFETY MEASURES TO PROTECT WORKERS AND ENVIRONMENT

Federica Paglietti, Paolo De Simone, Sergio Malinconico, Sergio Bellagamba — Sat, 15 Jun 2024 00:00:00 +0000

Asbestos is considered one of the most harmful occupational carcinogens causing more than 100,000 deaths per year and exposure to airborne asbestos ﬁbers is held responsible for half of the deaths from occupational cancer (caused by mesothelioma, asbestos-related cancer and asbestosis). Because of this, this substance is now banned in 52 Countries, including Italy, which prohibited the extraction, and marketing of asbestos in 1992. Many areas have therefore been identified in this European Country as highly contaminated by asbestos. Among them also the area of Monferrato, which includes the Municipality of Casale Monferrato and 46 neighboring municipalities. The Eternit asbestos cement plant, located in the municipality of Casale, caused the contamination. The aim of this paper is to describe the complex remediation activities conducted in this wide area, located in northern Italy, highlighting the main phases and the most important issues during the remediation execution; moreover the purpose is to recall the appropriate prevention and protection measures to adopt to prevent new asbestos exposures and to emphasize their importance. This study can serve as an important reference for the academic participants involved in this field at European or international level.

DIFFERENCE IN SURFACE FITTING WITH STANDARD AND MATRIX TOPOLOGY

Milan Ćurković, Andrijana Ćurković, Damir Vučina — Thu, 20 Jun 2024 00:00:00 +0000

This paper presents the impact of the surface topology of the scanned 3D object on parametric fitting. Whether it is a simple NURBS (Non-uniform rational B-spline) or a more complex hierarchical spline version, it is important to apply the fitting procedure. Here we describe the differences between fitting a surface with a given topology as a result of a 3D scanning system and a matrix topology of the surface, where the original surface is replaced by the result of a preset number of sections of the original geometry. We use the matrix and the free-form distribution. The former is more stable with respect to the distribution of the control point, the latter is numerically more suitable. In the future, we plan to adopt the free-form distribution to utilize the advantages of both distributions.

STRAIN GAUGE TESTING OF 3D-PRINTED CFRP SANDWICH STRUCTURE

Paweł Żur, Alicja Żur, Piotr Michalski, Andrzej Baier — Thu, 20 Jun 2024 00:00:00 +0000

In this article, the authors present composite sandwich-type CFRP structures and a study of their properties by strain gauge testing. The paper presents the modeling of a parameterized elementary unit serving as the core of a 3D printed structure using Fused Deposition Modelling (FDM) technology. The properties of these structures with different outer layers made of pure epoxy resin and resin with 10% and 20% carbon fiber powder were then investigated. Based on the results of the strain gauge tests, material models were reconstructed for each resin layer, which can be used in computer FEM studies of more complex components. As an application example, a strength analysis of the driver's seat of a Greenpower car made with printed sandwich structures coated with carbon fiber powder resin was conducted.

COMPREHENSIVE EVALUATION OF THERMAL PERFORMANCE AND TIME-LAG IN RESIDENTIAL APARTMENTS IN AMMAN

Dalia Salah, Ramzi Qasmeem Alrefaee — Thu, 20 Jun 2024 00:00:00 +0000

This exploration investigates the potential of enhancing energy efficiency in residential structures in Amman, Jordan, by introducing an innovative material termed "Phase Transition Substance with Fungal Integration (PTSF)." Through computational simulations using Autodesk-Revit, the analysis evaluates the thermal efficiency of a standard residential building, contrasting traditional construction materials with PTSF. The study centers on three crucial elements: outer walls (W.01), roof (R.01), and ground level slab (S.01), all initially not meeting prescribed thermal conductivity regulations. Integration of PTSF notably improves the thermal efficacy of the building's shell, aligning with Jordanian standards for thermal insulation. Furthermore, a systematic examination explores the time delay of materials within the residential envelope, revealing an average lag of approximately 8 hours. This lag implies that, with the incorporation of the PTSF layer, the envelope requires 8 hours to transmit external temperatures (e.g., 30°C) to attain the interior's peak temperature, underscoring the material's potential in curbing energy consumption.

INTELLIGENT NUMERICAL METHOD FOR STUDYING MAXWELL WILLIAMSON NANOFLUID FLOW WITH ACTIVATION ENERGY

Thu, 20 Jun 2024 00:00:00 +0000

The use of artificial intelligence and its techniques has become increasingly widespread in recent times. It is being used to solve stiff non-linear equations. Additionally, nanofluids play a pivotal role in studying heat transfer. All of this was the motivation for doing this work. This work investigates a two-dimensional magnetohydrodynamic stretched flow (2D-MHDSF) of Maxwell Williamson nanofluid (MWNF) affected by bioconvection and activation energy numerically through Levenberg-Marquardt backpropagation method (LMBM)-based artificial neural network approach. The mathematical formulation for the problem was obtained through non-linear partial differential equations (PDEs). The leading PDEs were transmitted into non-linear ordinary differential equations by similarity transformation variables. The reference results for the 2D-MHDSF-MWNF model are produced by the Lobatto IIIA method through different scenarios of specific parameters for the flow velocity, fluid temperature, nanoparticle concentration, and motile density profiles. Using obtained results as a dataset to apply the testing, training, and validation steps of the suggested LMBM for the 2D-MHDSF-MWNF model. The mean squared error, analysis of regression, and error histograms are presented to prove the efficiency and precision of the proposed method. The numerical results of LMBM are displayed as a study of the effects of different physical factors on flow dynamics for 2D-MHDSF-MWNF.

LAW ENFORCEMENT AGAINST TRADEMARK INFRINGEMENT IN INDONESIA

Etty Indrawati — Thu, 20 Jun 2024 00:00:00 +0000

Trademark as part of intellectual property rights is one of the most important elements in the business world. The number of trademark infringements that occurred in Indonesia from 2015 to 2023 shows an increasing trend. The purposes of this research are to explore and analyze the cause of trademark infringement and to investigate how efforts should be made to solve and reduce the number of trademark infringements in Indonesia. This research is normative legal research underpinned by interviews as well as through library research. Interviews were conducted with resource persons using interview guidelines. Then, data were analyzed using qualitative analysis. The result shows that the reason for trademark infringement is economic reasons. The offending party has bad intentions and assumes that the business whose trademark is to be imitated has good potential and person concerned can obtain a reasonable profit (good turnover potential) if using the same or similar trademark. The second is the party whose trademark is used by another party without rights needs to make a complaint about the trademark infringement because the infringement of intellectual property rights (including trademark infringement) is a complaint of violation that must be reported by the injured party to the law enforcer.

STRUCTURAL ANALYSIS OF A LIGHTWEIGHT ELECTRIC VEHICLE CHASSIS

Thu, 20 Jun 2024 00:00:00 +0000

This study presents a comprehensive investigation into the design and structural analysis of lightweight chassis for electric vehicles. A chassis needs to be able to withstand twist, shock, vibration, and other stresses caused by acceleration, braking, road condition, and shock initiated by other parts of a vehicle. It should carry a maximum load under all operating conditions. Two materials, 304L steel, and Ti-6AL-4V alloy were evaluated, with parameters such as total deformation, equivalent stress, and equivalent elastic strain under consideration. The outcome of the Finite Element Analysis revealed that Ti-6AL-4V can withstand higher stresses than 304L Steel. By investigating the static behaviors of the chassis under static loading due to weight and overload conditions, Ti-6AL-4V was chosen as a suitable replacement for a 304L Steel chassis.

TOWARDS LOCATING THE NIGHT OF DECREE IN RAMADAN MONTHS WITH MATHEMATICAL CALCULATIONS

Salih Hamza Abuelyamen — Thu, 20 Jun 2024 00:00:00 +0000

The Night of Decree (NOD) is the night when Allah the Glorified and Almighty descended the Holy Quran in Ramadan month; and He (TGAA) weighed this night to be better than thousand months. Muslims used to fast in Ramadan to gain this bounty. However, the location of this night was not explicitly indicated; but according to some narrations from the Prophet Mohammed (BPUH), he said to seek it in some proposed periods and individual nights. The methodology of the research is based on findings from previous research by the author on the construction of the Hijri calendar. The basic information of the previous research was derived from a verse in the Holy Quran from which we hypothesized that each 309 Hijri years equals completely 300 Gregorian years. A standard figure was developed from this equality and accumulated for all months. The monthly accumulated figures were broken down into daily accumulated figures (DAFs) for all Ramadan months in 309 Hijri years, and the NOD was identified from these DAFs. We managed to find the locations of this night, which are not far from what came in the prophetical narrations; moreover we added more information in this respect.