1. Introduction

Displays require phosphors with high photoluminescence intensity and high color purity. In addition, in micro-LED displays containing ultraviolet (UV) or blue LED arrays and phosphors, where chips are very small, the particle size of phosphors must be sufficiently small to suppress variation in hues among pixels. Therefore, there is a strong demand for a red phosphor that satisfy these conditions. To this end, novel Eu(III) complexes were introduced in a paper originally presented at the 2022 International Conference on Electronics Packaging as a candidate red phosphor for micro-LEDs [1].

In the case of inorganic phosphors, quantum yields decrease with decreasing phosphor particle size because they are present as fine particles in a polymer (Figure 1). Comparison of properties of the Lanthanide complexes and inorganic phosphors are shown in Table 1. The color purity of inorganic phosphors is low because of the large half widths of emission spectra.

Recently, lanthanide complexes, especially Eu(III) complexes, have attracted increasing attention for their application in emission devices, secure media, sensors, and so on [2–8]. Eu(III) complexes are attractive for display use because they produce sharp photoluminescence spectra with high color purity and can reproduce colors in large-area displays.

Figure 1: Comparison of inorganic phosphors and highly soluble lanthanide complexes in a polymer.

Table 1: Comparison of properties of the Lanthanide complexes and inorganic phosphors

In contrast to inorganic phosphors, particle size is not relevant to the theoretical quantum yield because each molecule of a Eu(III) complex has the function of absorbing and emitting light. From this point of view, Eu(III) complexes are promising candidate red phosphors for micro-LEDs. However, the photoluminescence intensity and solubility of Eu(III) complexes developed to date are insufficient for display use.

An Eu(III) ion itself has very low light absorption and weak emission. However, the emission of lanthanide ions can be enhanced through the antenna effect of ligands. b-diketonates are known to be effective ligands for enlarging photoluminescence intensity of Eu(III) complexes. b-Diketonates absorb light and transfer energy to lanthanide ions efficiently [9, 10]. The photoluminescence intensity of Eu(III) complexes depends largely on the substituents on the  b-diketonates because the triplet-state energy levels of b-diketonates are derived from the molecular structures of the substituents. However, it can be difficult to obtain sufficient emission intensity for use in emission devices simply by adjusting the substituents of b-diketonates.

There are two main types in ligands of lanthanide complexes. One is ionic ligands and the other is non-ionic ligands. b-diketonates are prominent ionic ligands and neutralize the charge of lanthanide ions. It is known that photoluminescence intensities are enhanced by the effects of non-ionic ligands in addition to b-diketonates. Phosphine oxide compounds are strong Lewis bases and excellent non-ionic ligands for enlarging photoluminescence intensity [11] (Figure 2).

Figure 2: Coordinating phosphine oxides to a Eu(III) ion.

However, there is room for further improvements in emission intensity. At the same time, the solubility of Eu(III) complexes with two identical phosphine oxides are too low to be dissolved in polymers or solvents. For this reason, Eu(III) complexes with low solubility have limited applications.

2. Experimental Section

2.1 Measurement of photoluminescence and excitation spectra

Photoluminescence and excitation spectra were measured at room temperature using a spectrofluorometer (Fluoromax 4, Horiba Jobin Yvon Inc.). Excitation and emission slit widths were set to 0.5 nm for measurement of emission spectra, and to 0.7 and 0.6 nm for measurement of excitation spectra, respectively. Measurement intervals are 1 nm. Scanning rate are 600 nm/min. Dark offset and corrections were applied to both the emission and excitation sites.

2.2 Measurement of emission lifetimes

Measurement of emission lifetimes were performed as follows. Each solution of the Eu(III) complexes was placed in a sealed cell and measured using the spectrofluorometer with the excitation wavelength set to 370 nm. Single exponential functions were used to fit the relative decay curves monitored at the maximum wavelength in order to calculate the emission lifetimes. c² values were in the range of >1.0 and <1.2.

2.3 Measurement of absolute quantum yields

Total absolute quantum yields (F_TOT) were measured using a photonic multichannel analyzer (PMA-12 C10027-01, Hamamatsu Photonics K.K). An integrating sphere was used for all measurements.

3. Results and Discussion

3-1. Eu(III) complexes with two different phosphine oxides

Figure 3 shows the relationships between molecular structures and photoluminescence spectra of Eu(III) complexes. The photoluminescence intensity of a Eu(III) complex with no phosphine oxide is usually very small, but when two triphenyl phosphine oxides coordinate, it increases to some extent. Furthermore, when two tributyl phosphine oxides coordinate, photoluminescence intensity increases further, and when both triphenyl and tributyl phosphine oxides coordinate, photoluminescence intensity becomes much higher [12]. The important point here is that coordination of two different phosphine oxide ligands is effective for increasing photoluminescence intensity [12–14]. Eu(III) complexes with two different phosphine oxides can be dissolved and are homogeneous at the molecular level in polymers. Polymers containing our Eu(III) complexes are colorless and transparent under room light but emit a pure color when irradiated with UV and 464-nm light.

3.2. Eu(III) complexes with an asymmetric diphosphine dioxide ligand

We detected the ligand exchange of phosphine oxide in Eu(III)-b-diketonates by NMR analysis [13]. However, ligand exchange is expected to have an undesirable effect on durability. To overcome this problem, we developed asymmetric diphosphine dioxide ligands (Figure 4). They have molecular structures consisting of two different phosphine oxide parts and methylene units and suppress ligand exchange via the chelate effect. In addition, the photoluminescence intensity of Eu(III)-b-diketonates with an asymmetric diphosphine dioxide ligand is higher than that with two different phosphine oxides [15, 16].

Tb(III) complexes with two different phosphine oxides or a single asymmetric diphosphine dioxide were also investigated [17]. It was found that solubilities of Tb(III) complexes were increased by coordination of two different phosphine oxide structures. However, photoluminescence intensities are strongly dependent on the substituents of b-diketonates because of the strong influences of back-energy transfer from excited Tb(III) ions to the ligands.

Figure 3. Comparison of the photoluminescence spectra of Eu(III) complexes in ethyl acetate at a concentration of 2×10^-4 mol/L at room temperature. Showing the effects of phosphine oxides and their combination on photoluminescence intensity [12].

Figure 4. Molecular structures of the asymmetric diphosphine dioxide ligand that increase the photoluminescence intensity of Eu(III) complexes (R¹=aromatic substituent, R²=aliphatic substituent).

3-3. Solubility of Eu(III) complexes with phosphine oxide ligands

Relationships between the molecular structures of Eu(III) complexes and solubility in solvents were investigated [18]. Eu(III) complexes with two different phosphine oxides are highly soluble in solvents and can be dissolved even in a fluorinated solvent. However, the solubility of Eu(III) complexes with an asymmetric diphosphine dioxide ligand is lower than that of Eu(III) complexes with two different phosphine oxides. We found that meta-substitution of trifluoromethyl groups (CF₃) on the phenyl groups of diphosphine dioxide ligands produces outstanding effects in terms of enhancing the solubility of Eu(III) complexes [19]. Similarly, the solubility of anthraquinone dichroic dyes in fluorinated media are markedly enhanced by the substitution of CF₃ groups [20–22].

3.4. Photoluminescence properties of Eu(III) complexes with an asymmetric diphosphine dioxide ligand

Figure 5 shows the optimal diphosphine dioxide ligand for Eu(III) complexes that increases both quantum yields and solubility [23]. Having CF₃ groups at the meta position of phenyl groups is one of the most important characteristics for achieving both high quantum yield and high solubility. Figures 6 and 7 show the relationships between excitation wavelength and quantum yields of Eu(III) complexes with and without diphosphine dioxide ligands, respectively [23].

Figure 5. Molecular structure of the asymmetric diphosphine dioxide ligand for Eu(III) complexes that increase the photoluminescence intensity (DPDO-mCF₃ ligand) [23].

The maximum total photoluminescence quantum yield (F_TOT) of Eu(III)(hfnh)₃ is small and the solid-state F_TOT of Eu(III)(hfnh)₃ is smaller than the solution-state F_TOT caused by concentration quenching (Figure 6). In contrast, F_TOT of Eu(III)(hfnh)₃(DPDO-mCF₃) is much greater than that of Eu(III)(hfnh)₃.  Furthermore, F_TOT is greater in the solid state than in the solution state. By coordinating the diphosphine dioxide ligands, quantum yields increase eminently. In the solid state, the maximum quantum yield reaches 0.82.

Diphosphine dioxide ligand functions as a separator, maintaining the distance among Eu(III) ions that prevent concentration quenching. In the solid state, there are no solvent molecules to decrease F_TOT of the Eu(III) complexes.

Figure 6. Action spectra (excitation wavelength vs. F_TOT) of Eu(III)(hfnh)₃ in the solid and solution states [23].

Figure 7. Action spectra (excitation wavelength vs. F_TOT) of Eu(III)(hfnh)₃(DPDO-mCF₃) in the solid and solution states [23].

3.5. Quantum yields of Eu(III) complexes with thienyl substituted diphosphine dioxide

Thienyl groups are electron-donating substituents that are expected to enhance the Lewis basicity of the oxygen atoms in diphosphine dioxide ligands. Dithienyl[3-(dioctylphosphinyl)-propyl] phosphine oxide (DTDOPO) and dithienyl[5-(dibutyl-phosphinyl)pentyl]phosphine oxide (DTDBPO) ligands were developed with the aim of forming stronger coordinate bonds with the Lewis acid Eu(III). A diphenyl[3-(dioctylphosphinyl)propyl]phosphine oxide (DPDO) ligand with phenyl groups instead of thienyl groups was prepared for comparison (Figure 8) [24].

Figure 8. Molecular structures of thienyl-substituted and phenyl-substituted diphosphine dioxides [24].

Figure 9. Quantum yields of Eu(III) complexes with thienyl-substituted and phenyl-substituted diphosphine dioxides both in the solid state and in solution (ethyl acetate) [24].

Figure 10. Molecular structures of Eu(III) complexes with a diphosphine dioxide ligand [25]. DPDiPBPO: diphenyl[4-(diisopropylphosphinyl)butyl]phosphine oxide, DPDBPBPO: diphenyl[4-(dibutylphosphinyl)butyl]phosphine oxide, DMPDBPBPO: di(4-methoxyphenyl)[4-(dibutylphosphinyl)butyl]phosphine oxide.

Figure 9 shows the relationships between concentrations in ethyl acetate and quantum yields of Eu(III)(fod)₃(DTDOPO), Eu(III)(fod)₃(DTBOPO), and Eu(III)(fod)₃(DPDO). The concentrations and quantum yields have a strong positive linear correlation and the quantum yields in the solid state (point with concentration [Log weight ratio] 0) are located on the extended line for Eu(III)(fod)₃(DTDOPO) and Eu(III)(fod)₃(DTBOPO) with thienyl groups. No concentration quenching was observed. As the concentration of Eu(III)(fod)₃(DPDO) increases, the differential coefficients become smaller. Research investigating the special feature of Eu(III) complexes with thienyl groups in the solid state is ongoing.

3.6. Effects of alkyl groups in diphosphine dioxide ligands on the photoluminescence properties of Eu(III) complexes

To investigate the effects of the molecular structures of diphosphine dioxide ligands on the photoluminescence properties of Eu(III) complexes, we prepared three Eu(III) complexes with the same molecular structure except for the slight difference in diphosphine dioxide ligands shown in Figure 10 [25].

Eu(III)(fod)₃(DPDiPPBPO) has i-propyl groups in a diphosphine dioxide ligand, while Eu(III)(fod)₃(DPDBPBPO) and Eu(III)(fod)₃(DMPDBPBPO) have n-butyl groups.

Figure 11. Photoluminescence spectra of the Eu(III) complexes Eu(III)(fod)₃(DPDiPBPO), Eu(III)(fod)₃(DPDBPBPO), and Eu(III)(fod)₃(DMPDBPBPO) in the solid state. They are excited at 370 nm [25].

The photoluminescence spectra of the Eu(III) complexes Eu(III)(fod)₃(DPDiPBPO), Eu(III)(fod)₃(DPDBPBPO), and Eu(III)(fod)₃(DMPDBPBPO) in the solid state are shown in Figure 11. The shapes of the Stalk splitting of the ⁵D₀→⁷F₂ transition differ among them. Of note, the half-width of the ⁵D₀→⁷F₂ transition of Eu(III)(fod)₃(DPDiPBPO) with i-propyl (i-Pr) substituted for the diphosphine dioxide ligand was 2 nm and conspicuously smaller compared with Eu(III)(fod)₃(DPDBPBPO) and Eu(III)(fod)₃(DMPDBPBPO) with n-butyl substituted for the diphosphine dioxide ligand. The smaller half-width means the ligand field has a higher symmetry.

Table 2. Photoluminescence properties of the Eu(III) complexes [25]

^aExperimental lifetime measured in solid. c² values were in the range of > 1.0 and < 1.2.

^bexperimental decay rate

^cRadiative lifetime calculated using the formula

 t_rad = 1/n³A_MD,0 ´ I_MD/I_TOT (n= 1.50).

^dRadiative decay rate

^eNon-radiative decay rate

^fIntrinsic quantum yield calculated using the formula

 F_Ln = t_exp / t_rad.

^gEnergy transfer efficiency

^hRatio between the integrated intensity of the ⁵D₀→ ⁷F₁ transition (I_MD) and the total integrated emission intensity ⁵D₀→ ⁷F_J(J = 0-6) (I_TOT)

ⁱTotal quantum yield measured in solid state. (Peak wavelength of the action spectrum (wavelength vs. quantum yield)).

^jCalculated from the formula I(⁵D₀→ ⁷F₂) / I(⁵D₀→ ⁷F₁)

Table 2 shows the photoluminescence properties of the Eu(III) complexes. The F_TOT of Eu(III)(fod)₃(DPDiPBPO) was smaller than that of others because of the smaller intrinsic quantum yield (F_Ln). The smaller ratio R and larger I_MD/I_TOT of Eu(III)(fod)₃(DPDiPBPO) showed that the Eu(III) complex with i-Pr groups in the diphosphine dioxide ligand had a higher symmetry in ligand fields compared with the others in the solid state. These results agree well with the result of the smaller half-width of Eu(III)(fod)₃(DPDiPBPO). These noticeable differences in properties are caused by the difference in molecular structures between the i-Pr and n-Bu groups in diphosphine dioxides.

Based on the above, we propose a hypothesis about F_TOT and diphosphine dioxide ligand structures: the steric hindrance of diphosphine dioxide ligands with n-Bu groups is larger than that of ligands with i-Pr groups, and a larger steric hindrance causes diphosphine dioxide ligands to have lower symmetry of the ligand field, thereby inducing a larger F_TOT. In the next section, we focus on the effects of steric hindrance in diphosphine dioxide ligands.

3.7. Elucidation of the effects of diphosphine dioxide ligands on the quantum yield and photoluminescence intensity of a 6-coordinate Eu(III)-b-diketonate complex

To elucidate the coordination effects of phosphine oxide ligands, the following 6-coordinate Eu(III) complex designed to have low luminescence and a large absorption coefficient was synthesized: (Tris{6,6,7,7,8,8,8-heptafluoro-1-[2-(9,9-dimethylfluorenyl)]-1,3-octanedionate} europium(III) (Eu(III)(hfod)₃) (Figure 12) [26].

Dimethylfluorenyl groups are bulky aromatic substituents with large absorption coefficients. Partially fluorinated alkyl groups in b-diketonates are also very bulky. The methylene units in partially fluorinated alkyl groups have the function of decreasing the energy transfer efficiency from the ligands to the Eu(III) ion.

Figure 12. Coordinating effects of DPDB ligand with Eu(III)(hfod)₃ with bulky b-diketonates, “hfod” [26].

The photoluminescence intensity of Eu(III)(hfod)₃ is dramatically enhanced by coordinating a DPDB ligand (generating Eu(III)(hfod)₃(DPDB)) due to the increased F_TOT, F_Ln, and F_ET in both the solution and solid states.

We propose the following hypothesis for the increase in F_TOT of 6-coordinate Eu(III) complex caused by the effects of the DPDB ligand. When a DPDB ligand coordinates with the Eu(III) ion, the positions of the nearest oxygen atoms around the Eu(III) ion are shifted by steric repulsion, and the relative positions of the nearest oxygen atoms become distorted. Ligand field is asymmetrized by the distorted coordination environment, and that increases F_TOT.

The norm of the effective dipole moment of the ligand field μ was defined [26]. We demonstrated that the energy transfer efficiencies from the lowest triplet state of the ligands to the ⁵D₁ level of the Eu(III) ion (Φ_ET) increases when the ligand fields of the Eu(III) ion become more asymmetric by coordinating the DPDB ligand.

3.8. High-sensitivity method for detecting the pesticide dichlorvos by using Eu(III)-b-diketonate as a quenching probe

Dichlorvos is a general-purpose insecticide with agricultural, household, and animal applications. However, it is harmful to humans, and thus a high-sensitivity method for detecting dichlorvos that provides results in a short time would be desirable.

We found that Eu(III)(hfnh)₃ was a highly sensitive luminescent probe for the pesticide dichlorvos. The photoluminescence intensity of Eu(III)(hfnh)₃ was drastically and rapidly decreased when a dilute solution of dichlorvos was added to the solutions of Eu(III)(hfnh)₃ (Figure 13) [27].

When a solution of dichlorvos was mixed with a solution of Eu(III)(hfnh)₃ and shaken, F_ET drastically decreased (0.64→ 0.15). The photoluminescence quenching of Eu(III)(hfnh)₃ by dichlorvos occurred before the energy transfer from b-diketonates to a Eu(III) ion between the dichlorvos molecules and the b-diketonates

The photoluminescence of Eu(III)(hfnh)₃ is not quenched by compounds with similar structures and has a favorable selectivity for dichlorvos. These results indicate that Eu(III)(hfnh)₃ is a strong candidate for a sensitive, selective, and quick method for detecting dichlorvos. Other organophosphorus pesticides can be selectively detected by other Eu(III)-b-diketonates.

Figure 13. Photoluminescence quenching of Eu(III)(hfod)₃ by the pesticide dichlorvos [27].

Figure 14. Colorless and transparent photoluminescence materials containing our Eu(III) complexes and/or Tb(III) complexes in a polymer [16].

3.9. Characteristics of colorless and transparent photoluminescence materials involved in our Eu(III) complexes and/or Tb(III) complexes in a polymer

We developed multiple lanthanide complexes having two different phosphine oxides or an asymmetric diphosphine dioxide that improved both photoluminescence intensity and solubility. When Eu(III) or Tb(III) complexes or both are dissolved in a polymer, materials that are colorless and have transparent photoluminescence under room light are produced. These materials emit pure red or green as well as yellow and orange intermediate colors when irradiated with UV or near-UV light (Figure 14) [16].

LED devices comprising a UV-light LED chip and a fluorescent layer consisting of a fluorinated polymer and Eu(III) complexes with two different phosphine oxides were prototyped. The developed devices emit a pure red color. The highest luminous flux obtained under optimum conditions, which to our knowledge is the best result reported as of 2007, was 870 m lumen/20 mA, when excited by a 402-nm LED chip (Figure 15) [28].

Figure 15. LED devices containing novel Eu(III) complexes in the fluorinated layer [28].

4. Conclusion

We found that coordination of two different phosphine oxide structures to a lanthanide ion is effective for enhancing the photoluminescence intensity and solubility of lanthanide complexes. An asymmetric diphosphine dioxide ligand consisting of two different phosphine oxide parts and methylene units produce further excellent effects in terms of enhancing the quantum yields and photoluminescence intensity of Eu(III) complexes. Asymmetric diphosphine dioxide ligands induce asymmetry in the ligand fields of Eu(III) complexes, thereby improving the quantum yields. Colorless and transparent photoluminescence materials can be obtained by dissolving Eu(III) complexes in polymers or solvents. These materials show great promise for use in LEDs as well as security and sensing devices.

We believe that our Eu(III) complexes have advantages over inorganic phosphors as red phosphors for use in micro-LED displays.

Acknowledgment

The author would like to thank Okuno Atsushi, Takahisa Kobayashi, Junichi Washizuka, Chiari Shimizu, Naruaki Watanabe, Akiko Yuzawa, and Huang Chingchun for fruitful discussions.

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5. Viktor Denkovski, Irena Stojmenovska, Goce Gavrilov, Vladimir Radevski, Vladimir Trajkovik, "Exploring Current Challenges on Security and Privacy in an Operational eHealth Information System", Advances in Science, Technology and Engineering Systems Journal, vol. 9, no. 2, pp. 45–54, 2024. doi: 10.25046/aj090206
6. Fazalur Rehman, Safwan Hashmi, "Enhancing Cloud Security: A Comprehensive Framework for Real-Time Detection, Analysis and Cyber Threat Intelligence Sharing", Advances in Science, Technology and Engineering Systems Journal, vol. 8, no. 6, pp. 107–119, 2023. doi: 10.25046/aj080612
7. Mario Cuomo, Federica Massimi, Francesco Benedetto, "Detecting CTC Attack in IoMT Communications using Deep Learning Approach", Advances in Science, Technology and Engineering Systems Journal, vol. 8, no. 2, pp. 130–138, 2023. doi: 10.25046/aj080215
8. Ivana Marin, Sven Gotovac, Vladan Papić, "Development and Analysis of Models for Detection of Olive Trees", Advances in Science, Technology and Engineering Systems Journal, vol. 8, no. 2, pp. 87–96, 2023. doi: 10.25046/aj080210
9. Richard Romero Izurieta, Segundo Moisés Toapanta Toapanta, Luis Jhony Caucha Morales, María Mercedes Baño Hifóng, Eriannys Zharayth Gómez Díaz, Oscar Marcelo Zambrano Vizuete, Luis Enrique Mafla Gallegos, José Antonio Orizaga Trejo, "Prototype to Identify the Capacity in Cybersecurity Management for a Public Organization", Advances in Science, Technology and Engineering Systems Journal, vol. 8, no. 1, pp. 108–115, 2023. doi: 10.25046/aj080113
10. Mostapha Harmouzi, Aziz Amari, Lhoussaine Masmoudi, "Conception and Simulation of an Electronic Nose Prototype for Olfactory Acquisition", Advances in Science, Technology and Engineering Systems Journal, vol. 8, no. 1, pp. 101–107, 2023. doi: 10.25046/aj080112
11. Segundo Moisés Toapanta Toapanta, Rodrigo Humberto Del Pozo Durango, Luis Enrique Mafla Gallegos, Eriannys Zharayth Gómez Díaz, Yngrid Josefina Melo Quintana, Joan Noheli Miranda Jimenez, Ma. Roció Maciel Arellano, José Antonio Orizaga Trejo, "Prototype to Mitigate the Risks, Vulnerabilities and Threats of Information to Ensure Data Integrity", Advances in Science, Technology and Engineering Systems Journal, vol. 7, no. 6, pp. 139–150, 2022. doi: 10.25046/aj070614
12. Tarek Nouioua, Ahmed Hafid Belbachir, "The Security of Information Systems and Image Processing Supported by the Quantum Computer: A review", Advances in Science, Technology and Engineering Systems Journal, vol. 7, no. 6, pp. 77–86, 2022. doi: 10.25046/aj070609
13. Muhammad Musleh Uddin, Kazi Rafiqul Islam, Md. Monirul Kabir, "An Improved Model to Analyze the Impact of Cyber-Attacks on Power Systems", Advances in Science, Technology and Engineering Systems Journal, vol. 7, no. 5, pp. 27–34, 2022. doi: 10.25046/aj070504
14. Kamil Halouzka, Ladislav Burita, Aneta Coufalikova, Pavel Kozak, Petr Františ, "A Comparison of Cyber Security Reports for 2020 of Central European Countries", Advances in Science, Technology and Engineering Systems Journal, vol. 7, no. 4, pp. 105–113, 2022. doi: 10.25046/aj070414
15. Tiny du Toit, Hennie Kruger, Lynette Drevin, Nicolaas Maree, "Deep Learning Affective Computing to Elicit Sentiment Towards Information Security Policies", Advances in Science, Technology and Engineering Systems Journal, vol. 7, no. 3, pp. 152–160, 2022. doi: 10.25046/aj070317
16. Afsah Sharmin, Farhat Anwar, S M A Motakabber, Aisha Hassan Abdalla Hashim, "A Secure Trust Aware ACO-Based WSN Routing Protocol for IoT", Advances in Science, Technology and Engineering Systems Journal, vol. 7, no. 3, pp. 95–105, 2022. doi: 10.25046/aj070311
17. Khosro Salmani, Ken Barker, "Leakage-abuse Attacks Against Forward Private Searchable Symmetric Encryption", Advances in Science, Technology and Engineering Systems Journal, vol. 7, no. 2, pp. 156–170, 2022. doi: 10.25046/aj070216
18. Kartit Zaid, Diouri Ouafaa, "Taxonomy of Security Techniques for Routing Protocols in Mobile Ad-hoc Networks", Advances in Science, Technology and Engineering Systems Journal, vol. 7, no. 2, pp. 25–31, 2022. doi: 10.25046/aj070203
19. Yusuke Nosaka, Miho Shinohara, Hidemi Ishikawa, Yuko Hoshino, Mitsuho Yamada, "Analysis of Reading Time and the Number of Characters within One Gazing Point", Advances in Science, Technology and Engineering Systems Journal, vol. 6, no. 6, pp. 137–144, 2021. doi: 10.25046/aj060618
20. Janusz Gurzynski, Lukasz Kajda, Marcin Tarasiuk, Tomasz Samotyjak, Zbigniew Stachowicz, Slawomir Kownacki, "Control and Monitoring Systems in Medium Voltage Distribution Networks in Poland – Current Status and Directions of Development", Advances in Science, Technology and Engineering Systems Journal, vol. 6, no. 6, pp. 112–118, 2021. doi: 10.25046/aj060615
21. Boris Kontsevoi, Sergei Terekhov, "TETRA™ Techniques to Assess and Manage the Software Technical Debt", Advances in Science, Technology and Engineering Systems Journal, vol. 6, no. 5, pp. 303–309, 2021. doi: 10.25046/aj060534
22. Osaretin Eboya, Julia Binti Juremi, "iDRP Framework: An Intelligent Malware Exploration Framework for Big Data and Internet of Things (IoT) Ecosystem", Advances in Science, Technology and Engineering Systems Journal, vol. 6, no. 5, pp. 185–202, 2021. doi: 10.25046/aj060521
23. Jianhua Yang, Lixin Wang, Yien Wang, "Enhance Student Learning Experience in Cybersecurity Education by Designing Hands-on Labs on Stepping-stone Intrusion Detection", Advances in Science, Technology and Engineering Systems Journal, vol. 6, no. 4, pp. 355–367, 2021. doi: 10.25046/aj060440
24. Yasuyuki Matsuura, Hiroki Takada, "Evaluation Studies of Motion Sickness Visually Induced by Stereoscopic Films", Advances in Science, Technology and Engineering Systems Journal, vol. 6, no. 4, pp. 241–251, 2021. doi: 10.25046/aj060428
25. Anh Nguyen-Duc, Manh-Viet Do, Quan Luong-Hong, Kiem Nguyen-Khac, Hoang Truong-Anh, "On the Combination of Static Analysis for Software Security Assessment – A Case Study of an Open-Source e-Government Project", Advances in Science, Technology and Engineering Systems Journal, vol. 6, no. 2, pp. 921–932, 2021. doi: 10.25046/aj0602105
26. Dancan Otieno Onyango, Christopher Ogolo Ikporukpo, John Olalekan Taiwo, Stephen Balaka Opiyo, Kevin Okoth Otieno, "Comparative Analysis of Land Use/Land Cover Change and Watershed Urbanization in the Lakeside Counties of the Kenyan Lake Victoria Basin Using Remote Sensing and GIS Techniques", Advances in Science, Technology and Engineering Systems Journal, vol. 6, no. 2, pp. 671–688, 2021. doi: 10.25046/aj060278
27. Bismark Tei Asare, Kester Quist-Aphetsi, Laurent Nana, "Node-Node Data Exchange in IoT Devices Using Twofish and DHE", Advances in Science, Technology and Engineering Systems Journal, vol. 6, no. 2, pp. 622–628, 2021. doi: 10.25046/aj060271
28. Zarina Din, Dian Indrayani Jambari, Maryati Mohd Yusof, Jamaiah Yahaya, "Challenges in IoT Technology Adoption into Information System Security Management of Smart Cities: A Review", Advances in Science, Technology and Engineering Systems Journal, vol. 6, no. 2, pp. 99–112, 2021. doi: 10.25046/aj060213
29. Saliha Assoul, Anass Rabii, Ounsa Roudiès, "An Operational Responsibility and Task Monitoring Method: A Data Breach Case Study", Advances in Science, Technology and Engineering Systems Journal, vol. 6, no. 1, pp. 1157–1163, 2021. doi: 10.25046/aj0601130
30. Devika K N, Ramesh Bhakthavatchalu, "Modified Blockchain based Hardware Paradigm for Data Provenance in Academia", Advances in Science, Technology and Engineering Systems Journal, vol. 6, no. 1, pp. 66–77, 2021. doi: 10.25046/aj060108
31. Pranay Bhardwaj, Carla Purdy, Nawar Obeidat, "A Novel Way to Design ADS-B using UML and TLA+ with Security as a Focus", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 6, pp. 1657–1665, 2020. doi: 10.25046/aj0506197
32. Hesham Aly El Zouka, Mustafa Mohamed Hosni, "Time Granularity-based Privacy Protection for Cloud Metering Systems", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 6, pp. 1278–1285, 2020. doi: 10.25046/aj0506152
33. Aicha Ousrhire, Hassane Oulidi Jarar, Abdessamad Ghafiri, "Multi-Criteria Decision Analysis Coupled with GIS and Remote Sensing Techniques for Delineating Suitable Artificial Aquifer Recharge Sites in Tafilalet Plain (Morocco)", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 6, pp. 1109–1124, 2020. doi: 10.25046/aj0506135
34. Boughanja Manale, Tomader Mazri, "5G, Vehicle to Everything Communication: Opportunities, Constraints and Future Directions", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 6, pp. 1089–1095, 2020. doi: 10.25046/aj0506132
35. Abdulla Obaid Al Zaabi, Chan Yeob Yeun, Ernesto Damiani, Gaemyoung, "An Enhanced Conceptual Security Model for Autonomous Vehicles", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 6, pp. 853–864, 2020. doi: 10.25046/aj0506102
36. Jim Scheibmeir, Yashwant Malaiya, "Multi-Model Security and Social Media Analytics of the Digital Twin", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 6, pp. 323–330, 2020. doi: 10.25046/aj050639
37. Hasn Mahmood Khudair, Taif Alawsi, Anwaar A. Aldergazly, A. H. Majeed, "Design and Implementation of Aerial Vehicle Remote Sensing and Surveillance System, Dehazing Technique Using Modified Dark Channel Prior", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 5, pp. 1111–1117, 2020. doi: 10.25046/aj0505135
38. Hani Ahmad-Assi, Nour Sultan Gammoh, Mariana Awni Al Bader, "Essential Features/Issues of a Multi-Phase Switching Synchronous Buck Regulator", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 5, pp. 1056–1063, 2020. doi: 10.25046/aj0505130
39. Khalid A. AlAfandy, Hicham Omara, Mohamed Lazaar, Mohammed Al Achhab, "Using Classic Networks for Classifying Remote Sensing Images: Comparative Study", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 5, pp. 770–780, 2020. doi: 10.25046/aj050594
40. Gautama Wijaya, Nico Surantha, "Multi-layered Security Design and Evaluation for Cloud-based Web Application: Case Study of Human Resource Management System", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 5, pp. 674–679, 2020. doi: 10.25046/aj050583
41. Khalid A. AlAfandy, Hicham, Mohamed Lazaar, Mohammed Al Achhab, "Investment of Classic Deep CNNs and SVM for Classifying Remote Sensing Images", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 5, pp. 652–659, 2020. doi: 10.25046/aj050580
42. Mika Karjalainen, Tero Kokkonen, "Review of Pedagogical Principles of Cyber Security Exercises", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 5, pp. 592–600, 2020. doi: 10.25046/aj050572
43. Khaldoon Fadhel Brethee, Ghalib Rzayyig Ibrahim, Rashaq Abdullah Mohammed, "Using Envelope Analysis and Compressive Sensing Method for Intelligent Fault Diagnosis of Ball Bearing", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 5, pp. 370–375, 2020. doi: 10.25046/aj050546
44. Liana Khamis Qabajeh, Mohammad Moustafa Qabajeh, "Detailed Security Evaluation of ARANz, ARAN and AODV Protocols", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 5, pp. 176–192, 2020. doi: 10.25046/aj050523
45. Pham Minh Nam, Phu Tran Tin, "Analysis of Security-Reliability Trade-off for Multi-hop Cognitive Relaying Protocol with TAS/SC Technique", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 5, pp. 54–62, 2020. doi: 10.25046/aj050508
46. Adamu Abdullahi Garba, Maheyzah Muhamad Siraj, Siti Hajar Othman, "An Explanatory Review on Cybersecurity Capability Maturity Models", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 4, pp. 762–769, 2020. doi: 10.25046/aj050490
47. Vu Nguyen Hoa Hong, Luong Tuan Anh, "Development Trends of Smart Cities in the Future – Potential Security Risks and Responsive Solutions", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 4, pp. 548–556, 2020. doi: 10.25046/aj050465
48. Maximo Giovani Tanzado Espinoza, Joseline Roxana Neira Melendrez, Luis Antonio Neira Clemente, "A Survey and an IoT Cybersecurity Recommendation for Public and Private Hospitals in Ecuador", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 3, pp. 518–528, 2020. doi: 10.25046/aj050364
49. Mainar Swari Mahardika, Achmad Nizar Hidayanto, Putu Agya Paramartha, Louis Dwysevrey Ompusunggu, Rahmatul Mahdalina, Farid Affan, "Measurement of Employee Awareness Levels for Information Security at the Center of Analysis and Information Services Judicial Commission Republic of Indonesia", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 3, pp. 501–509, 2020. doi: 10.25046/aj050362
50. Suchitra Abel, Yenchih Tang, Jake Singh, Ethan Paek, "Applications of Causal Modeling in Cybersecurity: An Exploratory Approach", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 3, pp. 380–387, 2020. doi: 10.25046/aj050349
51. Gillala Rekha, Shaveta Malik, Amit Kumar Tyagi, Meghna Manoj Nair, "Intrusion Detection in Cyber Security: Role of Machine Learning and Data Mining in Cyber Security", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 3, pp. 72–81, 2020. doi: 10.25046/aj050310
52. Segundo Moisés Toapanta Toapanta, Daniela Monserrate Moreira Gamboa, Luis Enrique Mafla Gallegos, "Analysis of the Blockchain for Adoption in Electronic Commerce Management in Ecuador", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 2, pp. 762–768, 2020. doi: 10.25046/aj050295
53. Segundo Moisés Toapanta Toapanta, Andrés Aurelio García Henriquez, Luis Enrique Mafla Gallegos, "Analysis of Vulnerabilities, Risks and Threats in the Process of Quota Allocation for the State University of Ecuador", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 2, pp. 673–682, 2020. doi: 10.25046/aj050283
54. Lylia Alouache, Mohamed Maachaoui, Rachid Chelouah, "Securing Hybrid SDN-based Geographic Routing Protocol using a Distributed Trust Model", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 2, pp. 567–577, 2020. doi: 10.25046/aj050271
55. Segundo Moisés Toapanta Toapanta, José David López Cobeña, Luis Enrique Mafla Gallegos, "Analysis of Cyberattacks in Public Organizations in Latin America", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 2, pp. 116–125, 2020. doi: 10.25046/aj050215
56. Karim El bouchti, Soumia Ziti, Fouzia Omary, Nassim Kharmoum, "New Solution Implementation to Protect Encryption Keys Inside the Database Management System", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 2, pp. 87–94, 2020. doi: 10.25046/aj050211
57. José Alomía-Lucero, Jorge Castro-Bedriñana, Doris Chirinos-Peinado, "Rooftop Urban Agriculture Model with Two Tomato Varieties (Lycopersicum esculentum Mill) and Toppings in the High Jungle – Peru", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 1, pp. 446–450, 2020. doi: 10.25046/aj050157
58. Amit Kumar Tyagi, A. Mohan Krishna, Shaveta Malik, Meghna Manoj Nair, Sreenath Niladhuri, "Trust and Reputation Mechanisms in Vehicular Ad-Hoc Networks: A Systematic Review", Advances in Science, Technology and Engineering Systems Journal, vol. 5, no. 1, pp. 387–402, 2020. doi: 10.25046/aj050150
59. Devulapalli Sudheer, Rajakumar Krishnan, "Multiscale Texture Analysis and Color Coherence Vector Based Feature Descriptor for Multispectral Image Retrieval", Advances in Science, Technology and Engineering Systems Journal, vol. 4, no. 6, pp. 270–279, 2019. doi: 10.25046/aj040634
60. Amine Kardi, Rachid Zagrouba, "Attacks classification and security mechanisms in Wireless Sensor Networks", Advances in Science, Technology and Engineering Systems Journal, vol. 4, no. 6, pp. 229–243, 2019. doi: 10.25046/aj040630
61. Evan Hurwitz, Chigozie Orji, "Multi Biometric Thermal Face Recognition Using FWT and LDA Feature Extraction Methods with RBM DBN and FFNN Classifier Algorithms", Advances in Science, Technology and Engineering Systems Journal, vol. 4, no. 6, pp. 67–90, 2019. doi: 10.25046/aj040609
62. Allae Erraissi, Abdessamad Belangour, "A Big Data Security Layer Meta-Model Proposition", Advances in Science, Technology and Engineering Systems Journal, vol. 4, no. 5, pp. 409–418, 2019. doi: 10.25046/aj040553
63. Segundo Moisés Toapanta Toapanta, Steven Xavier Romo Sañicela, Danny Wilfrido Barona Valencia, Luis Enrique Mafla Gallegos, "Analysis of Information Security for a Voting Process for Sectional Governments in Ecuador", Advances in Science, Technology and Engineering Systems Journal, vol. 4, no. 5, pp. 352–359, 2019. doi: 10.25046/aj040546
64. Alghamdi Abdullah, Mohammed Thanoon, Anwar Alsulami, "Toward a Smart Campus Using IoT: Framework for Safety and Security System on a University Campus", Advances in Science, Technology and Engineering Systems Journal, vol. 4, no. 5, pp. 97–103, 2019. doi: 10.25046/aj040512
65. Segundo Moisés Toapanta Toapanta, Allan Fabricio German Diaz, Darío Fernando Huilcapi Subia, Luis Enrique Mafla Gallegos, "Proposal for a Security Model for a Popular Voting System Process in Latin America", Advances in Science, Technology and Engineering Systems Journal, vol. 4, no. 5, pp. 53–60, 2019. doi: 10.25046/aj040507
66. Segundo Moisés Toapanta Toapanta, Gabriel Enrique Valenzuela Ramos, Félix Gustavo Mendoza Quimi, Luis Enrique Mafla Gallegos, "Prototype of a Security Architecture for a System of Electronic Voting for the Ecuador", Advances in Science, Technology and Engineering Systems Journal, vol. 4, no. 4, pp. 292–299, 2019. doi: 10.25046/aj040437
67. Vaibhav B. Vaijapurkar, Yerram Ravinder, "Development of Tactile Display and an Efficient Approach to Enhance Perceptual Analysis in Rehabilitation", Advances in Science, Technology and Engineering Systems Journal, vol. 4, no. 4, pp. 01–11, 2019. doi: 10.25046/aj040401
68. Segundo Moisés Toapanta Toapanta, Andrés Javier Bravo Jácome, Maximo Giovanny Tandazo Espinoza, Luis Enrique Mafla Gallegos, "An Immutable Algorithm Approach to Improve the Information Security of a Process for a Public Organization of Ecuador", Advances in Science, Technology and Engineering Systems Journal, vol. 4, no. 3, pp. 25–30, 2019. doi: 10.25046/aj040304
69. Toru Tanimura, Hiroki Takada, Akihiro Sugiura, Fumiya Kinoshita, Masumi Takada, "Effects of The Low-Resolution 3D Video Clip on Cerebrum Blood Flow Dynamics", Advances in Science, Technology and Engineering Systems Journal, vol. 4, no. 2, pp. 380–386, 2019. doi: 10.25046/aj040247
70. Robert M. Beswick, "Computer Security as an Engineering Practice: A System Engineering Discussion", Advances in Science, Technology and Engineering Systems Journal, vol. 4, no. 2, pp. 357–369, 2019. doi: 10.25046/aj040245
71. Shiree Hughes, Jiannan Zhai, Jason Hallstrom, "W.A.S.T.E. R.E.D.U.C.E.: Waste Auditing Sensor Technology to Enhance the Reduction of Edible Discards in University Cafeterias & Eateries", Advances in Science, Technology and Engineering Systems Journal, vol. 4, no. 2, pp. 45–64, 2019. doi: 10.25046/aj040207
72. Shruthi Narayanaswamy, Anitha Vijaya Kumar, "Application Layer Security Authentication Protocols for the Internet of Things: A Survey", Advances in Science, Technology and Engineering Systems Journal, vol. 4, no. 1, pp. 317–328, 2019. doi: 10.25046/aj040131
73. Constantine A. Pappas, "A Novel Pulse Position Modulator for Compressive Data Acquisition", Advances in Science, Technology and Engineering Systems Journal, vol. 4, no. 1, pp. 171–182, 2019. doi: 10.25046/aj040117
74. Lin Dong, Akira Rinoshika, "Analysis and Methods on The Framework and Security Issues for Connected Vehicle Cloud", Advances in Science, Technology and Engineering Systems Journal, vol. 3, no. 6, pp. 105–110, 2018. doi: 10.25046/aj030611
75. Emanuele Lindo Secco, Taye F. Agidew, Atulya Kumar Nagar, "An Optical-based Fingertip Force Sensor", Advances in Science, Technology and Engineering Systems Journal, vol. 3, no. 5, pp. 23–27, 2018. doi: 10.25046/aj030504
76. Hubert Bryan Riley, David Solomon Raj Kondru, Mehmet Celenk, "IR Sensing Embedded System Development for Prototype Mobile Platform and Multisensory Data Fusion for Autonomous Convoy", Advances in Science, Technology and Engineering Systems Journal, vol. 3, no. 4, pp. 372–377, 2018. doi: 10.25046/aj030438
77. Ola Surakhi, Mohammad Khanafseh, Yasser Jaffal, "An enhanced Biometric-based Face Recognition System using Genetic and CRO Algorithms", Advances in Science, Technology and Engineering Systems Journal, vol. 3, no. 3, pp. 116–124, 2018. doi: 10.25046/aj030316
78. Abul Kalam Azad, Md. Yamin Mollah, "EAES: Extended Advanced Encryption Standard with Extended Security", Advances in Science, Technology and Engineering Systems Journal, vol. 3, no. 3, pp. 51–56, 2018. doi: 10.25046/aj030307
79. Dhiman Chowdhury, Mrinmoy Sarkar, Mohammad Zakaria Haider, "A Cyber-Vigilance System for Anti-Terrorist Drives Based on an Unmanned Aerial Vehicular Networking Signal Jammer for Specific Territorial Security", Advances in Science, Technology and Engineering Systems Journal, vol. 3, no. 3, pp. 43–50, 2018. doi: 10.25046/aj030306
80. Nicola Fabiano, "The Internet of Things ecosystem: the blockchain and data protection issues", Advances in Science, Technology and Engineering Systems Journal, vol. 3, no. 2, pp. 1–7, 2018. doi: 10.25046/aj030201
81. Asma Meddeb, Hajer Jmii, Souad Chebbi, "Security Analysis and the Contribution of UPFC for Improving Voltage Stability", Advances in Science, Technology and Engineering Systems Journal, vol. 3, no. 1, pp. 404–411, 2018. doi: 10.25046/aj030149
82. Luca Dariz, Gianpiero Costantino, Massimiliano Ruggeri, Fabio Martinelli, "A Joint Safety and Security Analysis of message protection for CAN bus protocol", Advances in Science, Technology and Engineering Systems Journal, vol. 3, no. 1, pp. 384–393, 2018. doi: 10.25046/aj030147
83. Anass Sedrati, Abdellatif Mezrioui, "A Survey of Security Challenges in Internet of Things", Advances in Science, Technology and Engineering Systems Journal, vol. 3, no. 1, pp. 274–280, 2018. doi: 10.25046/aj030133
84. Hiroaki Anada, Seiko Arita, "Short CCA-Secure Attribute-Based Encryption", Advances in Science, Technology and Engineering Systems Journal, vol. 3, no. 1, pp. 261–273, 2018. doi: 10.25046/aj030132
85. Zeineb Zhioua, Rabea Ameur-Boulifa, Yves Roudier, "Framework for the Formal Specification and Verification of Security Guidelines", Advances in Science, Technology and Engineering Systems Journal, vol. 3, no. 1, pp. 38–48, 2018. doi: 10.25046/aj030106
86. Himanshu Upadhyay, Hardik Gohel, Alexander Pons, Leo Lagos, "Virtual Memory Introspection Framework for Cyber Threat Detection in Virtual Environment", Advances in Science, Technology and Engineering Systems Journal, vol. 3, no. 1, pp. 25–29, 2018. doi: 10.25046/aj030104
87. Susan Gottschlich, "A Taxonomy for Enhancing Usability, Flexibility, and Security of User Authentication", Advances in Science, Technology and Engineering Systems Journal, vol. 2, no. 6, pp. 225–235, 2017. doi: 10.25046/aj020627
88. Mohamed El Beqqal, Mostafa Azizi, "Review on security issues in RFID systems", Advances in Science, Technology and Engineering Systems Journal, vol. 2, no. 6, pp. 194–202, 2017. doi: 10.25046/aj020624
89. Mbunwe Muncho Josephine, "Design and Construction of a remote control switching device for household appliances application", Advances in Science, Technology and Engineering Systems Journal, vol. 2, no. 4, pp. 154–164, 2017. doi: 10.25046/aj020421
90. Moises Levy, Jason O. Hallstrom, "A Reliable, Non-Invasive Approach to Data Center Monitoring and Management", Advances in Science, Technology and Engineering Systems Journal, vol. 2, no. 3, pp. 1577–1584, 2017. doi: 10.25046/aj0203196
91. Saleh Mohamed Alnaeli, Melissa Sarnowski, Md Sayedul Aman, Ahmed Abdelgawad, Kumar Yelamarthi, "Source Code Vulnerabilities in IoT Software Systems", Advances in Science, Technology and Engineering Systems Journal, vol. 2, no. 3, pp. 1502–1507, 2017. doi: 10.25046/aj0203188
92. Ali Shuja Siddiqui, Yutian Gui, Jim Plusquellic, Fareena Saqib, "A Secure Communication Framework for ECUs", Advances in Science, Technology and Engineering Systems Journal, vol. 2, no. 3, pp. 1307–1313, 2017. doi: 10.25046/aj0203165
93. Daniel Fraunholz, Marc Zimmermann, Hans Dieter Schotten, "Towards Deployment Strategies for Deception Systems", Advances in Science, Technology and Engineering Systems Journal, vol. 2, no. 3, pp. 1272–1279, 2017. doi: 10.25046/aj0203161
94. Davar Pishva, "IoT: Their Conveniences, Security Challenges and Possible Solutions", Advances in Science, Technology and Engineering Systems Journal, vol. 2, no. 3, pp. 1211–1217, 2017. doi: 10.25046/aj0203153
95. Shu Wang, Vassilis Charissis, David K. Harisson, "Augmented Reality Prototype HUD for Passenger Infotainment in a Vehicular Environment", Advances in Science, Technology and Engineering Systems Journal, vol. 2, no. 3, pp. 634–641, 2017. doi: 10.25046/aj020381
96. Sarra Alqahtani, Rose Gamble, "Verifying the Detection Results of Impersonation Attacks in Service Clouds", Advances in Science, Technology and Engineering Systems Journal, vol. 2, no. 3, pp. 449–459, 2017. doi: 10.25046/aj020358
97. Minh T. Nguyen, "Energy-Efficient Mobile Sensing in Distributed Multi-Agent Sensor Networks", Advances in Science, Technology and Engineering Systems Journal, vol. 2, no. 3, pp. 245–253, 2017. doi: 10.25046/aj020334
98. Shaddrack Yaw Nusenu, "Directional Antenna Modulation Technique using A Two-Element Frequency Diverse Array", Advances in Science, Technology and Engineering Systems Journal, vol. 2, no. 3, pp. 227–232, 2017. doi: 10.25046/aj020331
99. Raid Khalid Hussein, Ahmed Alenezi, Hany F. Atlam, Mohammed Q Mohammed, Robert J. Walters, Gary B. Wills, "Toward Confirming a Framework for Securing the Virtual Machine Image in Cloud Computing", Advances in Science, Technology and Engineering Systems Journal, vol. 2, no. 4, pp. 44–50, 2017. doi: 10.25046/aj020406
100. Fatna Elmendili, Nisrine Maqran, Younes El Bouzekri El Idrissi, Habiba Chaoui, "A security approach based on honeypots: Protecting Online Social network from malicious profiles", Advances in Science, Technology and Engineering Systems Journal, vol. 2, no. 3, pp. 198–204, 2017. doi: 10.25046/aj020326