Physically unclonable security patterns created by electrospinning, and authenticated by two-step validation method

2021 ◽  
Author(s):  
Didem Taşcıoğlu ◽  
Arda Atçı ◽  
Seçil SEVİM ÜNLÜTÜRK ◽  
Serdar Ozcelik
Keyword(s):  
Social Problem ◽  
Uv Light ◽  
Spectral Information ◽  
Second Step ◽  
Spectral Signature ◽  
Fiber Network ◽  
Security Patterns ◽  
Electrospinning Method ◽  
Security Pattern ◽  
Random Patterns

Abstract Counterfeiting is a growing economic and social problem. For anticounterfeiting, random and inimitable droplet/fiber patterns were created by the electrospinning method as security tags that are detectable under UV light but invisible in daylight. To check the authenticity of the original security patterns created; images were collected with a simple smartphone microscope and a database of the recorded original patterns was created. The originality of the random patterns was checked by comparing them with the patterns recorded in the database. In addition, the spectral signature of the patterns in the droplet/fiber network was obtained with a simple and hand-held spectrometer. Thus, by reading the spectral signature from the pattern, the spectral information of the photoluminescent nanoparticles was verified and thus a second-step verification was established. In this way, anticounterfeiting technology that combines ink formula, unclonable security pattern creation and two-level verification is developed.

scholarly journals Systematic Literature Review of Security Pattern Research

2020 ◽  
Author(s):  
Hironori Washizaki ◽  
Tian Xia ◽  
Natsumi Kamata ◽  
Yoshiaki Fukazawa ◽  
Hideyuki Kanuka ◽  
...  
Keyword(s):  
Literature Review ◽  
Systematic Literature Review ◽  
System Development ◽  
Software System ◽  
Security Patterns ◽  
Secure Software ◽  
Security Pattern ◽  
Survey Results ◽  
Barriers To Implementation

Security patterns encompass security-related issues in secure software system development and operations that often appear in certain contexts. Since the late 1990s about 500 security patterns have been proposed. Although the technical components are well investigated, the direction, overall picture, and barriers to implementation are not. Here, a systematic literature review of 240 papers is used to devise a taxonomy for security pattern research. Our taxonomy and the survey results should improve communications among practitioners and researchers, standardize the terminology, and increase the effectiveness of security patterns.

The Effect of Needle Diameter on Optical Properties and Morphological Structure of La2O3- PVA Phosphor Nanofibers Prepared by Electrospinning Method

2020 ◽  
Vol 301 ◽  
pp. 18-26
Author(s):  
Hasma A. Wahab ◽  
Zainuriah Hassan ◽  
Naser Mahmoud Ahmed
Keyword(s):  
Optical Properties ◽  
Energy Gap ◽  
Uv Light ◽  
Light Emitting Diode ◽  
Morphological Structure ◽  
Average Diameter ◽  
X Ray Diffraction ◽  
Light Emitting ◽  
Electrospinning Method ◽  
Needle Diameter

Lanthanum Oxide-Polyvinyl alcohol (La2O3-PVA) phosphor nanofibers were prepared by electrospinning and investigation of the effect of needle diameter on the optical properties and morphological structure at the nanofibers was carried out. The average diameter of phosphor nanofibers have been evaluated for five different needle diameters. The resulting phosphor nanofibers were observed and anaylzed by X-ray diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM), Ultraviolet-visible Spectroscopy (UV-Vis) and HPC-2 Lightsource Colorimeter. The La2O3-PVA phosphor nanofibers were used in light down-conversion of UV light (365 nm) for the white light-emitting diode (WLED) application. The chromaticity coordinates (CIE) and correlated colour temperature (CCT) were measured for different phosphor nanofibers with different sizes of needle diameter (0.45,0.55,0.65,0.75,1.1) mm. The results revealed that the phosphor nanofibers formed by needle diameter of 0.65 mm places macromolecule in a better order and the average diameter increase from 40.08 nm to 87.27 nm after annealing followed by increasing in atomic percentage of lanthanum. The energy gap of resulting phosphor nanofibers is 3.5365 eV. An optimum colour rendering index (CRI) value of 70.20 is obtained. The white phosphor exhibited CIE values of 0.3536, 0.407 and CCT of 4890 K.

Transparent Ultraviolet Photodetectors Based on Ga2O3 Electrospun Nanowires

2018 ◽  
Vol 281 ◽  
pp. 710-715
Author(s):  
Muhammad Shahid ◽  
Tian Jun Li ◽  
Meng Fei Zhang ◽  
Jing Cheng ◽  
Yan Xing ◽  
...  
Keyword(s):  
Uv Light ◽  
Low Cost ◽  
Electrospun Nanofibers ◽  
High Transparency ◽  
Highly Sensitive ◽  
Electrospinning Method ◽  
Low Dimensional ◽  
Ultraviolet Photodetectors ◽  
High Photosensitivity ◽  
Excellent Stability

Ultraviolet photodetectors (PDs) based on low-dimensional (LD) gallium oxide nanofibers were synthesized and assembled by a low cost and scalable electrospinning method. Highly uniaxially aligned nanofibers were used to assemble photodetectors. Photoconductive investigations indicate that the prepared photodetectors (PDs) are highly sensitive to ultraviolet (UV) light. The prepared photodetectors have shown a high photosensitivity (103), fast photoresponse, excellent stability, and reproducibility under the illumination of UV light 254 nm. These electrospun nanofibers have also shown a high transparency (<85%) in the visible light 400-700 nm range. The high transparency of these nanobelts demonstrates their use for invisible UV photosensors.

Nanofibers - A Simple and Practical Way Forward for Air Pollution Abatement

2013 ◽  
Vol 756 ◽  
pp. 225-230 ◽  
Author(s):  
Naeem Shahzad ◽  
Qiao Chen
Keyword(s):  
Uv Light ◽  
Pollution Abatement ◽  
Glass Tube ◽  
Tube Reactor ◽  
Electrospinning Method ◽  
Before And After ◽  
Enhanced Adsorption ◽  
Air Pollution Abatement ◽  
Very High

Nanofibers have proved to be highly efficient due to their enhanced adsorption capacity, because of high pores and very high surfacearea. Pure and Sulphur doped TiO2nanofibers were synthesized using electrospinning method in this study to evaluate their destruction potential for H2S gas, using photocatalysis. Experiments were carried out under laboratory conditions using capillary glass tube reactor under UV light. 97% destruction was achieved using pure TiO2nanofibers while the destruction percentage decreased when S-doped TiO2nanofibers were replaced with the pure ones. Characterization of the nanofibers before and after running the experiments was carried out using XRD, SEM and EDX techniques. The destruction of H2S gas was measured in ppm using BioGas Analyser fitted with GPA1.8 Gas pod for H2S detection.

scholarly journals Construction and Optimization of Ecological Security Pattern Based on Spatial Syntax Classification—Taking Ningbo, China, as an Example

Land ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 380
Author(s):  
Yu Han ◽  
Chaoyue Yu ◽  
Zhe Feng ◽  
Hanchu Du ◽  
Caisi Huang ◽  
...  
Keyword(s):  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Landscape Connectivity ◽  
Development Trend ◽  
Ecological Security ◽  
Security Patterns ◽  
Ecological Corridors ◽  
Resistance Surface ◽  
Ecological Protection ◽  
Security Pattern

Urbanization is the development trend of all countries in the world, but it has caused considerable ecological problems that need to be alleviated by building ecological security patterns. This study took Ningbo as an example to construct and optimize an ecological security pattern. We analyzed land use types, normalized difference vegetation index, and landscape connectivity for ecological sources selection. In constructing the resistance surface, we considered natural and socio-economic factors. On this basis, we identified ecological corridors based on a minimum cumulative resistance model. Finally, the ecological security pattern was optimized through space syntax. Results showed that Ningbo has 18 ecological sources, with an area of 3051.27 km2 and 29 ecological corridors, with a length of 1172.18 km. Among them, 11 are first-level, 10 are second-level, and 8 are third-level corridors. After optimization, the area and protection cost of the ecological security pattern were significantly reduced, which can effectively alleviate the trade-off between ecological protection and economic development. This research can provide a reference for the construction and optimization of ecological security patterns and has reference significance for ecological protection in rapidly urbanized areas.

Security Patterns

2011 ◽  
pp. 75-111 ◽  
Author(s):  
Armstrong Nhlabatsi ◽  
Arosha Bandara ◽  
Shinpei Hayashi ◽  
Charles Haley ◽  
Jan Jurjens ◽  
...  
Keyword(s):  
Security Analysis ◽  
Research Area ◽  
Security Requirements ◽  
Software Systems ◽  
Security Patterns ◽  
Secure Systems ◽  
Modeling Approaches ◽  
Security Pattern ◽  
Security Modeling ◽  
Active Research

Addressing the challenges of developing secure software systems remains an active research area in software engineering. Current research efforts have resulted in the documentation of recurring security problems as security patterns. Security patterns provide encapsulated solutions to specific security problems and can be used to build secure systems by designers with little knowledge of security. Despite this benefit, there is lack of work that focus on evaluating the capabilities of security analysis approaches for their support in incorporating security analysis patterns. This chapter presents evaluation results of a study we conducted to examine the extent to which constructs provided by security requirements engineering approaches can support the use of security patterns as part of the analysis of security problems. To achieve this general objective, the authors used a specific security pattern and examined the challenges of representing this pattern in some security modeling approaches. The authors classify the security modeling approaches into two categories: problem and solution and illustrate their capabilities with a well-known security patterns and some practical security examples. Based on the specific security pattern they have used our evaluation results suggest that current approaches to security engineering are, to a large extent, capable of incorporating security analysis patterns.

scholarly journals Influence of ZnO, SiO2 and TiO2 on the aging process of PLA fibers produced by electrospinning method

2019 ◽  
Vol 140 (4) ◽  
pp. 1769-1778 ◽  
Author(s):  
Karolina Kosowska ◽  
Piotr Szatkowski
Keyword(s):  
Structural Changes ◽  
Uv Light ◽  
Total Reflection ◽  
Attenuated Total Reflection ◽  
Poly Lactic Acid ◽  
Uv Resistance ◽  
Scanning Calorimetry ◽  
Uv Aging ◽  
Electrospinning Method ◽  
Key Factor

Abstract The aim of this work was to study the effect of ceramics particles addition (SiO2, ZnO, TiO2) on the ultraviolet (UV) aging of poly(lactic acid) nonwovens fabricated using electrospinning method. The resistance to aging is a key factor for outdoor and medical applications (UV light sterilization). Nonwovens were placed in special chamber with UV light. Changes of physicochemical properties were recorded using differential scanning calorimetry and attenuated total reflection Fourier-transform infrared spectroscopy. The fibers’ morphology was studied by using scanning electron microscopy. Obtained results clearly showed that only PLA fibers with ZnO particles gained an increase in UV resistance. The paper presents a description of structural changes taking place under the influence of UV aging processes and describes the mechanisms of this process and the effect of ceramic addition on the lifetime of such materials.

Fluorescence Spectral Imaging as a Tool for Locating Uranium Deposited on Surfaces

2009 ◽  
Author(s):  
David L. Monts ◽  
Guangjun Wang ◽  
Yi Su ◽  
Ping-Rey Jang ◽  
Charles A. Waggoner
Keyword(s):  
Bandpass Filter ◽  
Uv Light ◽  
Visible Region ◽  
Spectral Imaging ◽  
Spectral Information ◽  
Uranyl Compounds ◽  
Uranium Compounds ◽  
Field Samples ◽  
Quantitative Fluorescence ◽  
Metallic Uranium

In the environment, metallic uranium readily oxidizes to form uranium compounds that contain the uranyl (UO2+2) moiety. For more than a hundred and fifty years, it has been known that when illuminated with ultraviolet (UV) light, uranyl compounds exhibit characteristic fluorescence in the visible region (450–650 nm). We report our efforts to develop a transportable, quantitative Fluorescence Spectral Imaging (FSI) system as a tool for locating and quantifying uranyl compounds dispersed in soils and on other surfaces. A project is underway to develop a set of sensors to locate expended depleted uranium (DU) rounds and to process soil and debris to recover the material from domestic firing ranges. The FSI system can also be utilized to monitor excavation of DU munitions and separation of uranyl compounds from soils. FSI images are acquired by illuminating a surface with a UV light and using a narrow bandpass filter on a camera, recording an image of the resulting fluorescence. The FSI image provides both spatial and spectral information. The FSI system is described and its performance characterized using field samples.

scholarly journals Electrospinning Preparation and Photocatalytic Activity of Porous TiO2Nanofibers

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Shanhu Liu ◽  
Baoshun Liu ◽  
Kazuya Nakata ◽  
Tsuyoshi Ochiai ◽  
Taketoshi Murakami ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Uv Light ◽  
Ethanol Solution ◽  
Titanium Tetraisopropoxide ◽  
X Ray Diffraction ◽  
Carbon Nanospheres ◽  
Transmission Electron ◽  
Electrospinning Method ◽  
Subsequent Calcination

Porous TiO2nanofibers were prepared via a facile electrospinning method. The carbon nanospheres were mixed with the ethanol solution containing both poly(vinylpyrrolidone) and titanium tetraisopropoxide for electrospinning; and subsequent calcination of as-spun nanofibers led to thermal decomposition of carbon nanospheres, leaving behind pores in the TiO2nanofibers. The morphology and phase structure of the products were investigated with scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). Furthermore, the photocatalytic activity of porous TiO2nanofibers was evaluated by photodecomposition of methylene blue under UV light. Results showed that the porous TiO2nanofibers have higher surface area and enhanced photocatalysis activity, compared to nonporous TiO2nanofibers.

scholarly journals Rapid photocatalytic degradation of phenol from water using composite nanofibers under UV

2020 ◽  
Vol 32 (1) ◽  
Author(s):  
Alaa Mohamed ◽  
Samy Yousef ◽  
Walaa S. Nasser ◽  
T. A. Osman ◽  
Alexander Knebel ◽  
...  
Keyword(s):  
Photocatalytic Degradation ◽  
Composite Nanofibers ◽  
Uv Light ◽  
Major Effect ◽  
Clean Water ◽  
Catalyst Amount ◽  
Dynamic Filtration ◽  
Photodegradation Mechanism ◽  
Electrospinning Method ◽  
The Stability

Abstract Background The removal of phenol from aqueous solution via photocatalytic degradation has been recognized as an environmentally friendly technique for generating clean water. The composite nanofibers containing PAN polymer, CNT, and TiO2 NPs were successfully prepared via electrospinning method. The prepared photocatalyst is characterized by SEM, XRD, and Raman spectroscopy. Different parameters are studied such as catalyst amount, the effect of pH, phenol concentration, photodegradation mechanism, flow rate, and stability of the composite nanofiber to evaluate the highest efficiency of the photocatalyst. Results The composite nanofibers showed the highest photodegradation performance for the removal of phenol using UV light within 7 min. The pH has a major effect on the photodegradation of phenol with its maximum performance being at pH 5. Conclusions Given the stability and flexibility of the composite nanofibers, their use in a dynamic filtration is possible and can be even reused after several cycles.

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