bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of the Gas-Atomization Pressure and Annealing Temperature on the Microstructure and Performance of FeSiBCuNb Nanocrystalline Soft Magnetic Composites
Authors: Li Guanzhi , Shi Guibing , Miao Hongyi , Liu Dan , Li Zongzhen , Wang Mingxu , Wang Li
Published: February 2023

FeSiBCuNb powders prepared by the gas atomization method generally exhibit a wide particle size distribution and a high degree of sphericity. In addition, the correspondingly prepared nanocrystalline soft magnetic composites (NSMCs) perform good service stability. In this paper, effects of the gas-atomization pressure and annealing temperature on the microstructure and soft magnetic properties of FeSiBCuNb powders and NSMCs are investigated. The results show that the powders obtained by a higher gas-atomization pressure possess a larger amorphous ratio and a smaller average crystallite size, which contribute to the better soft magnetic performance of the NSMCs. After being annealed at 550 °C for 60 min, the NSMCs show a much better performance than those treated by the stress-relief annealing process under 300 °C, which indicates that the optimization of the soft magnetic properties resulting from the precipitation of the α-Fe(Si) nanocrystalline largely overwhelms the deterioration caused by the grain growth of the pre-existing crystals. In addition, the annealed NSMCs prepared by the powders with the gas-atomization pressure of 4 MPa show the best performance in this work, μe = 33.32 (f = 100 kHz), Hc = 73.08 A/m and Pcv = 33.242 mW/cm3 (f = 100 kHz, Bm = 20 mT, sine wave).
Application of the Improved POA-RF Model in Predicting the Strength and Energy Absorption Property of a Novel Aseismic Rubber-Concrete Material
Authors: Mei Xiancheng , Cui Zhen , Sheng Qian , Zhou Jian , Li Chuanqi
Published: February 2023

The application of aseismic materials in foundation engineering structures is an inevitable trend and research hotspot of earthquake resistance, especially in tunnel engineering. In this study, the pelican optimization algorithm (POA) is improved using the Latin hypercube sampling (LHS) method and the Chaotic mapping (CM) method to optimize the random forest (RF) model for predicting the aseismic performance of a novel aseismic rubber-concrete material. Seventy uniaxial compression tests and seventy impact tests were conducted to quantify this aseismic material performance, i.e., strength and energy absorption properties and four other artificial intelligence models were generated to compare the predictive performance with the proposed hybrid RF models. The performance evaluation results showed that the LHSPOA-RF model has the best prediction performance among all the models for predicting the strength and energy absorption property of this novel aseismic concrete material in both the training and testing phases (R2: 0.9800 and 0.9108, VAF: 98.0005% and 91.0880%, RMSE: 0.7057 and 1.9128, MAE: 0.4461 and 0.7364; R2: 0.9857 and 0.9065, VAF: 98.5909% and 91.3652%, RMSE: 0.5781 and 1.8814, MAE: 0.4233 and 0.9913). In addition, the sensitive analysis results indicated that the rubber and cement are the most important parameters for predicting the strength and energy absorption properties, respectively. Accordingly, the improved POA-RF model not only is proven as an effective method to predict the strength and energy absorption properties of aseismic materials, but also this hybrid model provides a new idea for assessing other aseismic performances in the field of tunnel engineering.
Study on the Adsorption Behavior of Polymeric Dispersants to S-ZnF Particles during Grinding Process
Authors: Huang Guanghua , Wu Haohan , Liu Zhijun , Hu Hanlin , Guo Shifeng
Published: February 2023

Three sodium polyacrylate copolymers PD0x (Poly acrylic acid-co-sodium 4-vinylbenzenesulfonate or PD01; Poly acrylic acid-co-sodium 4-vinylbenzenesulfonate-co-hydroxyethyl methacrylate or PD02 and Poly methyl methacrylate-co-acrylic acid-co-sodium 4-vinylbenzenesulfonate-co-hydroxyethyl methacrylate or PD03) were synthesized as water-based dispersants for grinding red–brown pigment ZnFe1.2Cr0.8O4 particles prepared by the solid phase method (S-ZnF). The particle size distribution, viscosity of suspensions, and adsorption capacity of dispersants were explored by laser particle size analysis, viscometer, and thermogravimetry (TG), respectively. The application of 2 wt.% dispersant PD02 in the S-ZnF suspension ground for 90 min can deliver a finer product with the narrower particle size distribution. The added dispersant PD02 in the grinding process of the S-ZnF particles exhibits a suitable viscosity of the suspension and generates more hydrogen bonds on the S-ZnF particle surface. The sulfonic acid groups (SO3−) and carboxylic acid groups (-COO−) in the dispersant PD02 can also provide a strong charge density, which is favorable for the dispersion and grinding of the S-ZnF particles in the suspensions. Furthermore, the adsorption behavior of polymeric dispersant PD02 adsorbed on the S-ZnF particles surface was simulated and analyzed by adsorption thermodynamic models and adsorption kinetic models. It is indicated that the adsorption thermodynamic behavior of dispersant PD02 adsorbed on the S-ZnF particles surface follows the Langmuir model, and the adsorption process is endothermic and a random process with increased confusion during the grinding process. In addition, the adsorption kinetics of dispersant PD02 adsorbed on the S-ZnF particles surface are more in line with the pseudo-first-order kinetic models. Therefore, the adsorption process of dispersant PD02 on the S-ZnF particles surface can be considered as a single-surface adsorption process.
Study on Crystal Growth of Tobermorite Synthesized by Calcium Silicate Slag and Silica Fume
Authors: Yang Zhijie , Fang Chengyang , Jiao Yang , Zhang De , Kang Dong , Wang Kaiyue
Published: February 2023

In order to high-value utilize the secondary solid waste calcium silicate slag (CSS) generated in the process of the extraction of alumina from fly ash, in this paper, tobermorite was synthesized using CSS and silica fume (SF) at different hydrothermal synthesis times. The hydrothermal synthesis was evaluated by means of XRD, SEM, EDS, and micropore analysis, and the results discussed. The results indicate that β-dicalcium silicate, the primary phase in the CSS, partially hydrates at the beginning of hydrothermal synthesis conditions to form mesh-like crystal C-S-H (calcium-rich) and calcium hydroxide. It then reacts with SF to form yarn-like crystal C-S-H (silicon-rich) and then furtherly grows into large flake-like crystal C-S-H (silicon-rich) at 3 h. When the synthesis time is 4 h, β-dicalcium silicate completely hydrates, and crystal C-S-H (calcium-rich) and calcium hydroxide further reacts with large flake-like crystal C-S-H (silicon-rich) to generate medium flake-like tobermorite. With the increase in time, the crystal of hydrothermal synthesis grows in the order of medium flake-like tobermorite, small flake-like tobermorite, strip flake-like tobermorite, fibrous-like tobermorite, and spindle-like tobermorite, and the APV, APD, and SSA show a trend of decreasing first, then increasing, and then decreasing. Meanwhile, strip flake-like tobermorite with a higher average pore volume (APV), average pore diameter (APD), and specific surface area (SSA) can be synthesized at 6 h.
Monolithic Multicolor Emissions of InGaN-Based Hybrid Light-Emitting Diodes Using CsPbBr3 Green Quantum Dots
Authors: Oh Jae-Hyeok , Cho Seung-Beom , Park Il-Kyu , Lee Sung-Nam
Published: February 2023

To address the increasing demand for multicolor light-emitting diodes (LEDs), a monolithic multicolor LED with a simple process and high reliability is desirable. In this study, organic–inorganic hybrid LEDs with violet and green wavelengths were fabricated by depositing CsPbBr3 perovskite green quantum dots (QDs) as the light-converting material on InGaN-based violet LEDs. As the injection current was increased, the total electroluminescence (EL) intensities of the hybrid LEDs increased, whereas the light-converted green emission efficiency of the CsPbBr3 QDs decreased. The maximum green-to-violet EL spectral intensity ratio of the hybrid LEDs with CsPbBr3 QDs was achieved with the injection current of <10 mA. Moreover, the EL spectral ratio of the green-to-violet emission decreased at an injection current of 100 mA. The light-conversion intensity of the CsPbBr3 QDs decreased linearly as the junction temperature of the hybrid LEDs was increased with increasing injection current, similar to the temperature-dependent photoluminescence degradation of CsPbBr3 QDs. In addition, the junction temperature of the hybrid LED was minimized by pulse injection to suppress the thermal degradation of QDs and increase the light conversion efficiency to green emission. Therefore, the overall emission spectrum color coordinates of the hybrid LEDs exhibited a red shift from violet to blue in the low-current region and a blue shift toward violet as the green emission of the QDs was decreased above 10 mA.
Tissue-Level Laser-Lok Implants Placed with a Flapless Technique: A 4-Year Clinical Study
Authors: Spinelli Andrea , Zamparini Fausto , Romanos Georgios , Gandolfi Maria Giovanna , Prati Carlo
Published: February 2023

Background: The present study aims to analyze the use of Laser-Lok microtextured neck implants placed with a transmucosal surgical approach. The marginal bone level (MBL) and periodontal parameters were evaluated in a cohort prospective 4-year clinical study. Methods: A total of 41 implants were placed in 36 healthy consecutive patients (16 males, 20 females, mean age 60 ± 9 years). Tapered tissue level implants, characterized by a 2.0 mm laser-microtextured neck, were used with a flapless approach. Customized abutments and provisional resin crowns were positioned. Definitive metal–ceramic crowns were cemented approximately 4 months after insertion. Periapical radiographs were taken after 1, 3, 6, 12, 36 and 48 months from implant placement to evaluate MBL. Gingival thickness (thin/thick), plaque score (PS) and bleeding on probing (BoP) were evaluated. Results: After 48 months, all implants were safe from complications. No complications, peri-implantitis, early implant failures or mucositis occurred. The survival rate was 100%. Mean MBL during the follow-up was −0.15 ± 0.18 at T1, −0.29 ± 0.29 at T3, −0.45 ± 0.37 at T6, −0.53 ± 0.45 at T12, −1.06 ± 1.13 at T 36 and −1.10 ± 0.89 at T 48. Implants placed 2–3 months after tooth extraction revealed lower MBL variation when compared to those placed immediately (in fresh extraction sockets) or in completely healed ridges (delayed group). Narrower diameter implants (3.8 mm) showed significantly higher MBL variation when compared to 4.6 diameter implants. Multilevel analysis at T48 revealed that among all the evaluated variables, implant diameter was the factor mostly associated with MBL modifications (p = 0.027). Conclusion: This 4-year clinical study supports the use of Laser-Lok implants placed at tissue level with a flapless approach. A limited bone loss during the 48-month follow-up was observed. Periodontal parameters were stable with no sign of inflammation or soft tissue alteration. The use of Laser-Lok implants with transmucosal surgery represents a suitable technique with a minimally invasive approach.
Derivatives of Pyridazine with Phenoxazine and 9,9-Dimethyl-9,10-dihydroacridine Donor Moieties Exhibiting Thermally Activated Delayed Fluorescence
Authors: Skhirtladze Levani , Bezvikonnyi Oleksandr , Keruckienė Rasa , Dvylys Lukas , Mahmoudi Malek , Labanauskas Linas , Ariffin Azhar , Grazulevicius Juozas V.
Published: February 2023

Two compounds based on pyridazine as the acceptor core and 9,9-dimethyl-9,10-dihydroacridine or phenoxazine donor moieties were designed and synthesized by Buchwald–Hartwig cross-coupling reaction. The electronic, photophysical, and electrochemical properties of the compounds were studied by ultraviolet-visible spectroscopy (UV-vis), photoluminescence spectrometry, differential scanning calorimetry, thermogravimetric analysis, and cyclic voltammetry. The compounds are characterized by high thermal stabilities. Their 5% weight loss temperatures are 314 and 336 °C. Complete weight loss of both pyridazine-based compounds was detected by TGA, indicating sublimation. The derivative of pyridazine and 9,9-dimethyl-9,10-dihydroacridine is capable of glass formation. Its glass transition temperature is 80 °C. The geometries and electronic characteristics of the compounds were substantiated using density functional theory (DFT). The compounds exhibited emission from the intramolecular charge transfer state manifested by positive solvatochromism. The emission in the range of 534–609 nm of the toluene solutions of the compounds is thermally activated delayed fluorescence with lifetimes of 93 and 143 ns, respectively.
Influence of Imperfections on the Effective Stiffness of Multilayer Corrugated Board
Authors: Mrówczyński Damian , Garbowski Tomasz
Published: February 2023

There are many possible sources of potential geometrical inaccuracies in each layer of corrugated board during its manufacture. These include, among others, the processes of wetting the corrugated layers during profiling, the process of accelerated drying, the gluing process, and any mechanical impact of the pressure rollers on the cardboard. Work taking into account all the above effects in numerical modeling is not well described in the literature. Therefore, this article presents a simple and practical procedure that allows us to easily account for geometric imperfections in the calculation of the effective stiffness of corrugated board. As a main tool, the numerical homogenization based on the finite element method (FE) was used here. In the proposed procedure, a 3D model of a representative volumetric element (RVE) of a corrugated board is first built. The numerical model can include all kinds of geometrical imperfections and is used to calculate the equivalent tensile and bending stiffnesses. These imperfections were included in the 3D numerical model by appropriate modeling of individual layers, taking into account their distorted shape, which was obtained on the basis of a priori buckling analysis. This paper analyzes different types of buckling in order to find the most representative one. The proposed procedure is easy to implement and fully scalable.
Laboratory Study of the Effects of the Mixer Type and Mixing Time on the Volumetric Properties and Performance of a HMA with 30 Percent Reclaimed Asphalt Pavement
Authors: Bérubé Marc-André , Lamothe Sébastien , Bilodeau Kevin , Carter Alan
Published: February 2023

This study examined the effects of the laboratory mixer type and mixing time on a hot-mix asphalt (HMA) using three different types of mixers and four different mixing times. The asphalt mix used is a semi-open graded mix (ESG-10) with 30% reclaimed asphalt pavement (RAP), and a range of tests were conducted including bitumen extraction by ignition, particle size distribution, maximum specific gravity (Gmm), a SUPERPAVE gyratory compactor (SGC), bulk specific gravity (Gmb), indirect tensile stiffness modulus (ITSM), and indirect tensile strength (IDT). The statistical analysis of variance (ANOVA) was also applied to quantify the effect of mixer type and mixing time. The results indicated that both mixing type and time had a significant effect on the properties of the HMA (volumetric properties and compactability) and that the type of mixer used also affected the performance of the HMA (stiffness and cracking resistance), with some mixers producing asphalt mixes with better properties than others. The study ultimately demonstrated that it is possible to produce a mix that exhibits good performance and meets or does not meet the compactability specifications depending on the mixer type used.
Effect of Cu on the Formation of Reversed Austenite in Super Martensitic Stainless Steel
Authors: Jiang Wen , Zhao Kunyu
Published: February 2023

We investigated the effect of Cu on the formation of reversed austenite in super martensitic stainless steel by using X-ray diffraction (XRD), a transmission electron microscope (TEM) and an energy-dispersive spectrometer (EDS). Our results showed that the microstructure of the steels comprised tempered martensite and diffused reversed austenite after the steels were quenched at 1050 °C and tempered at 550–750 °C. The volume fraction of reversed austenite in the steel with 3 wt.% of Cu (3Cu) was more than that with 1.5 wt.% of Cu (1.5Cu). The transmission electron microscope results revealed that the reversed austenite in 1.5Cu steel mainly had the shape of a thin strip, while that in 3Cu steel had a block shape. The nucleation points and degree of Ni enrichment of reversed austenite in 3Cu steel were higher than those in 1.5Cu steel. The reversed austenite was more likely to grow in ε-Cu enriched regions. Therefore, Cu can promote reversed austenite nucleation and growth. The mechanical properties of 3 Cu steel are obviously better than those of 1.5Cu steel when tempered at 550–650 °C.
Recent Trends in Hydroxyapatite Supplementation for Osteoregenerative Purposes
Authors: Zastulka Ana , Clichici Simona , Tomoaia-Cotisel Maria , Mocanu Aurora , Roman Cecilia , Olteanu Cristian-Doru , Culic Bogdan , Mocan Teodora
Published: February 2023

Bone regeneration has gained attention in the biomedical field, which has led to the development of materials and synthesis methods meant to improve osseointegration and cellular bone activity. The properties of hydroxyapatite, a type of calcium phosphate, have been researched to determine its advantages for bone tissue engineering, particularly its biocompatibility and ability to interact with bone cells. Recently, the advantages of utilizing nanomolecules of hydroxyapatite, combined with various substances, in order to enhance and combine their characteristics, have been reported in the literature. This review will outline the cellular and molecular roles of hydroxypatite, its interactions with bone cells, and its nano-combinations with various ions and natural products and their effects on bone growth, development, and bone repair.
Optical Properties Investigation of Upconverting K2Gd(PO4)(WO4):20%Yb3+,Tm3+ Phosphors
Authors: Grigorjevaite Julija , Katelnikovas Arturas
Published: February 2023

Nowadays, scientists are interested in inorganic luminescence materials that can be excited with UV or NIR radiation and emit in the visible range. Such inorganic materials can be successfully used as luminescent or anti-counterfeiting pigments. In this work, we report the synthesis and optical properties investigation of solely Tm3+ doped and Yb3+/Tm3+ co-doped K2Gd(PO4)(WO4) phosphors. The single-phase samples were prepared using a solid-state reaction method. The Tm3+ concentration was changed from 0.5% to 5%. Downshifting and upconversion emission studies were performed under 360 nm and 980 nm excitation, respectively. Yb3+ ions were used as sensitizers in the K2Gd(PO4)(WO4) phosphors to transfer the captured energy to Tm3+ ions. It turned out that under UV excitation, phosphors emitted in the blue spectral area regardless of the presence or absence of Yb3+. However, a very strong deep-red (~800 nm) emission was observed when Yb3+ and Tm3+-containing samples were excited with a 980 nm wavelength laser. It is interesting that the highest upconversion emission in the UV/Visible range was achieved for 20% Yb3+, 0.5% Tm3+ doped sample, whereas the sample co-doped with 20% Yb3+, 2% Tm3+ showed the most intensive UC emission band in the NIR range. The materials were characterized using powder X-ray diffraction and scanning electron microscopy. Optical properties were studied using steady-state and kinetic downshifting and upconversion photoluminescence spectroscopy.
Application of Digital Image Correlation to Evaluate Strain, Stiffness and Ductility of Full-Scale LVL Beams Strengthened by CFRP
Authors: Bakalarz Michał Marcin , Tworzewski Paweł Piotr
Published: February 2023

Due to limitations of traditional measuring methods, a necessity of verification of applicability of optical measuring systems in different fields of science is required. The paper presents the application of a non-contact, non-destructive ARAMIS optical system in the analysis of static work of unstrengthened and strengthened laminated veneer lumber beams (LVL) with composite materials, subjected to a four-point bending test. The beams were strengthened with Carbon Fiber Reinforced Polymer (CFRP) sheets and laminates. The sheets were bonded to the external surfaces in three configurations differing in the number of layers applied and the degree of coverage of the side surface. The CFRP laminates were glued into predrilled grooves and applied to the underside of the beams. An adhesive based on epoxy resin was used. The scope of the work includes analysis of the strain distribution, stiffness and ductility. The analysis was performed on the basis of measurements made with an optical measurement system. The strain analysis indicated a change of the distribution of the strain in the compressive zone from linear for the unstrengthened to bilinear for the strengthened beams. The stiffness increase was equal from 14% up to 45% for the application of the CFRP laminates in the grooves and CFRP sheets bonded externally, respectively. Similar improvement was obtained for the ductility.
ZnTe Crystal Multimode Cryogenic Thermometry Using Raman and Luminescence Spectroscopy
Authors: Borisov Evgenii V. , Kalinichev Alexey A. , Kolesnikov Ilya E.
Published: February 2023

In this study, ZnTe crystal was applied to provide precise thermal sensing for cryogenic temperatures. Multiple techniques, namely Raman and photoluminescence spectroscopies, were used to broaden the operating temperature range and improve the reliability of the proposed thermometers. Raman-based temperature sensing could be applied in the range of 20–100 K, while luminescence-based thermometry could be utilized in a narrower range of 20–70 K. However, the latter strategy provides better relative thermal sensitivity and temperature resolution. The best thermal performances based on a single temperature-dependent parameter attain Sr = 3.82% K−1 and ΔT = 0.12 K at T = 50 K. The synergy between multiple linear regression and multiparametric thermal sensing demonstrated for Raman-based thermometry results in a ten-fold improvement of Sr and a two-fold enhancement of ΔT. All studies performed testify that the ZnTe crystal is a promising multimode contactless optical sensor for cryogenic thermometry.
Characterization of 2D Electrical Feedback Flow Control Valve
Authors: Dai Quanchao , Zhao Jiantao , Li Sheng , Jia Wenang
Published: February 2023

We proposed a novel 2D electric feedback flow control valve to solve the problem of low integration and control accuracy of flow control valves. The torque motor of the valve drives the 2D piston to rotate, and the rotational motion is converted to axial motion and drives the spool. The differential pressure feedback rod on the valve body can accurately measure the differential pressure of the oil inlet and outlet and cooperate with the spool displacement to form a closed loop of flow. This loop of flow then overcomes the influence of the valve port’s load change on the flow. We first established the mathematical model of the valve, obtained the transfer function, and performed the stability analysis. Then, we used AMESim as a platform for simulation analysis. Finally, we conducted the experimental verification of the valve. The verification showed the following characteristics of the valve. The hysteresis loop is 4.4%. The linearity is 1.6%. The response time is about 44 ms. The amplitude bandwidth is about 17 Hz. The phase bandwidth is about 28 Hz. The valve’s steady-state flow error is less than 8%, suggesting its broad application prospect in the aerospace and military fields.
Application of a Model-Based Method to the Online Detection of Rotating Rectifier Faults in Brushless Synchronous Machines
Authors: Mahtani Kumar , Guerrero José M. , Beites Luis F. , Platero Carlos A.
Published: February 2023

Converters are one of the most sensible components of any power conversion system when it comes to electrical faults. Moreover, if these converters are used in a rotating system, as is the case with rotating rectifiers used in brushless synchronous machines, apart from also being exposed to mechanical effects and thus having a greater likelihood of failure, no access is available directly, causing a lack of available measurements for condition monitoring. This paper applies a model-based method to the online detection of open-diode faults, shorted-diode faults and exciter open-phase faults in the rotating rectifiers of brushless synchronous machines. The applied method relies on the comparison between the measured and the theoretical exciter field currents, the latter computed through a healthy machine model from the machine actual output values. The proposed protection strategy stands out for its computational simplicity and its non-invasiveness, which makes its industrial application straightforward without the need of any further equipment or adaptation. Its applicability has been verified through a double approach, on the one hand, through computer simulations, and, on the other hand, through experimental tests, achieving satisfactory results. The research conducted proves that with the proposed method, given reasonable measurement and model estimation typical errors of less than 5%, positive differences between the measured and the theoretical exciter field currents of more than 13%, 200% and 30% for open-diode faults, shorted-diode faults and exciter open-phase faults, respectively, are detectable with at least a 95% confidence interval.
Design of Confidence-Integrated Denoising Auto-Encoder for Personalized Top-N Recommender Systems
Authors: Khan Zeshan Aslam , Chaudhary Naveed Ishtiaq , Abbasi Waqar Ali , Ling Sai Ho , Raja Muhammad Asif Zahoor
Published: February 2023

A recommender system not only “gains users’ confidence” but also helps them in other ways, such as reducing their time spent and effort. To gain users’ confidence, one of the main goals of recommender systems in an e-commerce industry is to estimate the users’ interest by tracking the users’ transactional behavior to provide a fast and highly related set of top recommendations out of thousands of products. The standard ranking-based models, i.e., the denoising auto-encoder (DAE) and collaborative denoising auto-encoder (CDAE), exploit positive-only feedback without utilizing the ratings’ ranks for the full set of observed ratings. To confirm the rank of observed ratings (either low or high), a confidence value for each rating is required. Hence, an improved, confidence-integrated DAE is proposed to enhance the performance of the standard DAE for solving recommender systems problems. The correctness of the proposed method is authenticated using two standard MovieLens datasets such as ML-1M and ML-100K. The proposed study acts as a vital contribution for the design of an efficient, robust, and accurate algorithm by learning prominent latent features used for fast and accurate recommendations. The proposed model outperforms the state-of-the-art methods by achieving improved P@10, R@10, NDCG@10, and MAP scores.
Convergence Analysis for Yosida Variational Inclusion Problem with Its Corresponding Yosida Resolvent Equation Problem through Inertial Extrapolation Scheme
Authors: Rajpoot Arvind Kumar , Ishtyak Mohd , Ahmad Rais , Wang Yuanheng , Yao Jen-Chih
Published: February 2023

In this paper, we study a Yosida variational inclusion problem with its corresponding Yosida resolvent equation problem. We mention some schemes to solve both the problems, but we focus our study on discussing convergence criteria for the Yosida variational inclusion problem in real Banach space and for the Yosida resolvent equation problem in q-uniformly smooth Banach space. For faster convergence, we apply an inertial extrapolation scheme for both the problems. An example is provided.
A Chaotic Image Encryption Method Based on the Artificial Fish Swarms Algorithm and the DNA Coding
Authors: Zhu Yue , Wang Chunhua , Sun Jingru , Yu Fei
Published: February 2023

Aiming at the problems of small key space and weak resistance to differential attacks in existing encryption algorithms, we proposed a chaotic digital image encryption scheme based on an optimized artificial fish swarm algorithm and DNA coding. First, the key is associated with the ordinary image pixel through the MD5 hash operation, and the hash value generated by the ordinary image is used as the initial value of the hyper-chaotic system to increase the sensitivity of the key. Next, the artificial fish school algorithm is used to scramble the positions of pixels in the block. In addition, scrambling operation between blocks is proposed to increase the scrambling effect. In the diffusion stage, operations are performed based on DNA encoding, obfuscation, and decoding technologies to obtain encrypted images. The research results show that the optimized artificial fish swarm algorithm has good convergence and can obtain the global optimal solution to the greatest extent. In addition, simulation experiments and security analysis show that compared with other encryption schemes, the scheme proposed in this paper has a larger key space and better resistance to differential attacks, indicating that the proposed algorithm has better encryption performance and higher security.
Efficient Net-XGBoost: An Implementation for Facial Emotion Recognition Using Transfer Learning
Authors: Punuri Sudheer Babu , Kuanar Sanjay Kumar , Kolhar Manjur , Mishra Tusar Kanti , Alameen Abdalla , Mohapatra Hitesh , Mishra Soumya Ranjan
Published: February 2023

Researchers are interested in Facial Emotion Recognition (FER) because it could be useful in many ways and has promising applications. The main task of FER is to identify and recognize the original facial expressions of users from digital inputs. Feature extraction and emotion recognition make up the majority of the traditional FER. Deep Neural Networks, specifically Convolutional Neural Network (CNN), are popular and highly used in FER due to their inherent image feature extraction process. This work presents a novel method dubbed as EfficientNet-XGBoost that is based on Transfer Learning (TL) technique. EfficientNet-XGBoost is basically a cascading of the EfficientNet and the XGBoost techniques along with certain enhancements by experimentation that reflects the novelty of the work. To ensure faster learning of the network and to overcome the vanishing gradient problem, our model incorporates fully connected layers of global average pooling, dropout and dense. EfficientNet is fine-tuned by replacing the upper dense layer(s) and cascading the XGBoost classifier making it suitable for FER. Feature map visualization is carried out that reveals the reduction in the size of feature vectors. The proposed method is well-validated on benchmark datasets such as CK+, KDEF, JAFFE, and FER2013. To overcome the issue of data imbalance, in some of the datasets namely CK+ and FER2013, we augmented data artificially through geometric transformation techniques. The proposed method is implemented individually on these datasets and corresponding results are recorded for performance analysis. The performance is computed with the help of several metrics like precision, recall and F1 measure. Comparative analysis with competent schemes are carried out on the same sample data sets separately. Irrespective of the nature of the datasets, the proposed scheme outperforms the rest with overall rates of accuracy being 100%, 98% and 98% for the first three datasets respectively. However, for the FER2013 datasets, efficiency is less promisingly observed in support of the proposed work.
Poly(alkyl-biphenyl pyridinium)-Based Anion Exchange Membranes with Alkyl Side Chains Enable High Anion Permselectivity and Monovalent Ion Flux
Authors: Yang Jin , Chen Qian , Afsar Noor Ul , Ge Liang , Xu Tongwen
Published: February 2023

Poly(alkyl-biphenyl pyridinium)-based anion exchange membranes with alkyl side chains were synthesized for permselective anion separation. By altering the length of the grafted side chain, the hydrophilicity and other attributes of the membranes could be controlled. The QDPAB-C5 membrane with the best comprehensive performance exhibited a Cl− ion flux of 3.72 mol m−2 h−1 and a Cl−/SO42− permselectivity of 15, which are significantly better than the commercial Neosepta ACS membrane. The QDPAB-C5 membranes with distinct microscopic phase separation structures formed interconnected hydrophilic/hydrophobic ion channels and exhibited excellent ion flux and permselectivity for other anionic systems (NO3−/SO42−, Br−/SO42−, F−/SO42−, NO3−/Cl−, Br−/Cl−, and F−/Cl−) as well. Furthermore, the influence of alkyl side chain length on the membranes’ ion flux and permselectivity in electrodialysis was investigated, which may be attributed to the alterations in ion channels and hydrophobic regions of the membranes. This work provides an effective strategy for the development of monovalent anion permselective membranes.
Phospholipases and Membrane Curvature: What Is Happening at the Surface?
Authors: Fanani María Laura , Ambroggio Ernesto Esteban
Published: February 2023

In this revision work, we emphasize the close relationship between the action of phospholipases and the modulation of membrane curvature and curvature stress resulting from this activity. The alteration of the tridimensional structure of membranes upon the action of phospholipases is analyzed based on studies on model lipid membranes. The transient unbalance of both compositional and physical membrane properties between the hemilayers upon phospholipase activity lead to curvature tension and the catalysis of several membrane-related processes. Several proteins’ membrane-bound and soluble forms are susceptible to regulation by the curvature stress induced by phospholipase action, which has important consequences in cell signaling. Additionally, the modulation of membrane fusion by phospholipase products regulates membrane dynamics in several cellular scenarios. We commented on vesicle fusion in the Golgi-endoplasmic system, synaptic vesicle fusion to the plasma membrane, viral membrane fusion to host cell plasma membrane and gametes membrane fusion upon acrosomal reaction. Furthermore, we explored the modulation of membrane fusion by the asymmetric adsorption of amphiphilic drugs. A deep understanding of the relevance of lipid membrane structure, particularly membrane curvature and curvature stress, on different cellular events leads to the challenge of its regulation, which may become a powerful tool for pharmacological therapy.
Effect of Co-Coated Al2O3 Composite Powders on LPBF-Manufactured CoCrMo Alloy
Authors: Zhang Lehui , Liu Wei , Cao Yu , Sun Haoxin , Xie Qiusheng , Lai Junyun , Bai Peikang
Published: February 2023

In this study, we systematically examined the influence mechanisms of introduced cobalt coated alumina (Co-coated Al2O3) particles on the microstructure and properties of cobalt-chromium-molybdenum (CoCrMo) alloy printed by Laser Powder Bed Fusion (LPBF). The Co-coated Al2O3 composite powders with different density of cobalt coating were prepared by varying Al2O3 load from 1 g/150 mL to 2 g/150 mL during the electroless plating process. Then they were mixed with CoCrMo powders in the proportion of 1 wt.% and formed standard samples by LPBF technology. The results showed that the addition of Co-coated Al2O3 particles improved the friction performance of CoCrMo alloys significantly. The wear depth of CCM@2Al2O3 was only 2.18 μm and the wear volume of it was about 10% of pure CoCrMo alloy. The CoCrMo alloy introduced the Co-coated Al2O3 particles with a 1 g/150 mL Al2O3 load formed metal-ceramic bonding interface, which solved the problem of poor wettability between Al2O3 and matrix in LPBF process. Such CoCrMo alloy exhibited excellent tensile properties and the mean microhardness of it reached 379.9 ± 3.5 HV0.5.
Extraction of Sodium Tungstate from Tungsten Ore by Pyrometallurgical Smelting
Authors: Xu Liqiang , Zhao Baojun
Published: February 2023

Tungsten is one of the strategic metals produced from tungsten ores through sodium tungstate. The hydrometallurgical process is a common technology for extracting sodium tungstate from high-grade tungsten concentrates. The grade of tungsten ore is decreasing, and the mineral processing to produce a high-grade concentrate suitable for the hydrometallurgical process is becoming more difficult. It is desirable to develop a new technology to effectively recover tungsten from the complex low-grade tungsten ores. A fundamental study on the pyrometallurgical processing of wolframite was carried out through thermodynamic calculations and high-temperature experiments. The wolframite was reacted with Na2CO3 and SiO2 at 1050–1200 °C and then leached with water to obtain a sodium tungstate solution as a feed for the traditional process of APT (Ammonium paratungstate). The factors affecting the extraction rate of tungsten from wolframite were investigated in air and neutral atmosphere. The extraction rate of tungsten was found to increase with increasing Na2O content and decrease with increasing SiO2 addition and temperature. The extraction rate in argon was higher than that in air for wolframite.
Effect of Grain Size on Dynamic Compression Behavior and Deformation Mechanism of ZK60 Magnesium Alloy
Authors: Liu Xuanyu , Mao Pingli , Zhou Le , Wang Xueting , Wang Zhi , Wang Feng , Wei Ziqi , Liu Zheng
Published: February 2023

The dynamic compression deformation of 3 µm, 15 µm and 25 µm grain size ZK60 alloys under high-strain-rate compression is systematically studied. Dynamic compression experiments at a strain rate of 1700 s−1 were conducted using a split Hopkinson pressure bar, and the microstructure of the specimen was characterized via electron backscatter diffraction and transmission electron microscopy, as well as via the calculation of Schmid factors. The results showed that the alloy exhibited the decrease in yield strength and peak stress as the grain size increased under dynamic compression. The grain refinement in the alloy was conducive to the activation of basic slip. In turn, an increase in the grain size caused the transition in the main deformation mechanism from pyramidal  slip to {10−12} tensile twinning and pyramidal  slip. Based on these deformation mechanisms, the Johnson-Cook constitutive equation with different grain sizes was modified, and the fitting results were in accordance with the experimental data.
Mass-Spectrometry-Based Lipidomics Discriminates Specific Changes in Lipid Classes in Healthy and Dyslipidemic Adults
Authors: Sánchez-Vinces Salvador , Garcia Pedro Henrique Dias , Silva Alex Ap. Rosini , Fernandes Anna Maria Alves de Piloto , Barreto Joyce Aparecida , Duarte Gustavo Henrique Bueno , Antonio Marcia Aparecida , Birbrair Alexander , Porcari Andreia M. , Carvalho Patricia de Oliveira
Published: February 2023

Triacylglycerols (TAGs) and cholesterol lipoprotein levels are widely used to predict cardiovascular risk and metabolic disorders. The aim of this study is to determine how the comprehensive lipidome (individual molecular lipid species) determined by mass spectrometry is correlated to the serum whole-lipidic profile of adults with different lipidemic conditions. The study included samples from 128 adults of both sexes, and they were separated into four groups according to their lipid profile: Group I—normolipidemic (TAG < 150 mg/dL, LDL-C < 160 mg/dL and HDL-c > 40 mg/dL); Group II—isolated hypertriglyceridemia (TAG ≥ 150 mg/dL); Group III—isolated hypercholesterolemia (LDL-C ≥ 160 mg/dL) and Group IV—mixed dyslipidemia. An untargeted mass spectrometry (MS)-based approach was applied to determine the lipidomic signature of 32 healthy and 96 dyslipidemic adults. Limma linear regression was used to predict the correlation of serum TAGs and cholesterol lipoprotein levels with the abundance of the identified MS-annotated lipids found in the subgroups of subjects. Serum TAG levels of dyslipidemic adults have a positive correlation with some of the MS-annotated specific TAGs and ceramides (Cer) and a negative correlation with sphingomyelins (SMs). High-density lipoprotein-cholesterol (HDL-C) levels are positively correlated with some groups of glycerophosphocholine, while low-density lipoprotein-cholesterol (LDL-C) has a positive correlation with SMs.
Metabolomics Reveal the Regulatory Effect of Polysaccharides from Fermented Barley Bran Extract on Lipid Accumulation in HepG2 Cells
Authors: Zhao Yan-Sheng , Tong Xin-Meng , Wu Xue-Mei , Bai Juan , Fan Song-Tao , Zhu Ying , Zhang Jia-Yan , Xiao Xiang
Published: February 2023

Barley bran has potential bioactivities due to its high content of polyphenols and dietary fiber, etc. Fermentation has been considered as an effective way to promote the functional activity of food raw materials. In this study, polysaccharides from barley bran extract fermented by Lactiplantibacillus plantarum dy-1 (FBBE-PS) were analyzed, and its effects on lipid accumulation and oxidative stress in high-fat HepG2 cells induced by sodium oleate were evaluated. The results showed that the molecular weight decreased and monosaccharide composition of polysaccharides changed significantly after fermentation. In addition, 50 μg/mL FBBE-PS could reduce the triglyceride (TG) content and reaction oxygen species (ROS) level in high-fat HepG2 cells by 21.62% and 30.01%, respectively, while increasing the activities of superoxide dismutase (SOD) and catalase (CAT) represented by 64.87% and 22.93%, respectively. RT-qPCR analysis revealed that FBBE-PS could up-regulate the lipid metabolism-related genes such as ppar-α, acox-1 and cpt-1α, and oxidation-related genes such as nrf2, ho-1, nqo-1, sod1, cat, etc. The metabolomics analysis indicated that FBBE-PS could alleviate lipid deposition by inhibiting the biosynthesis of unsaturated fatty acids, which is consistent with the downregulation of scd-1 expression. It is demonstrated that fermentation can alter the properties and physiological activities of polysaccharides in barley bran, and FBBE-PS exhibited an alleviating effect on lipid deposition and oxidative stress in high-fat cells.
Using Ontologies to Create Machine-Actionable Datasets: Two Case Studies
Authors: Hippolyte Jean-Laurent , Romanchikova Marina , Bevilacqua Maurizio , Duncan Paul , Hunt Samuel E. , Grasso Toro Federico , Piette Anne-Sophie , Neumann Julia
Published: February 2023

Achieving the highest levels of compliance with the FAIR (findable, accessible, interoperable, reusable) principles for scientific data management and stewardship requires machine-actionable semantic representations of data and metadata. Human and machine interpretation and reuse of measurement datasets rely on metrological information that is often specified inconsistently or cannot be inferred automatically, while several ontologies to capture the metrological information are available, practical implementation examples are few. This work aims to close this gap by discussing how standardised measurement data and metadata could be presented using semantic web technologies. The examples provided in this paper are machine-actionable descriptions of Earth observation and bathymetry measurement datasets, based on two ontologies of quantities and units of measurement selected for their prominence in the semantic web. The selected ontologies demonstrated a good coverage of the concepts related to quantities, dimensions, and individual units as well as systems of units, but showed variations and gaps in the coverage, completeness and traceability of other metrology concept representations such as standard uncertainty, expanded uncertainty, combined uncertainty, coverage factor, probability distribution, etc. These results highlight the need for both (I) user-friendly tools for semantic representations of measurement datasets and (II) the establishment of good practices within each scientific community. Further work will consequently investigate how to support ontology modelling for measurement uncertainty and associated concepts.
Precise Position Control of Holonomic Inchworm Robot Using Four Optical Encoders
Authors: Tanabe Kengo , Shiota Masato , Kusui Eiji , Iida Yohei , Kusama Hazumu , Kinoshita Ryosuke , Tsukui Yohei , Minegishi Rintaro , Sunohara Yuta , Fuchiwaki Ohmi
Published: February 2023

In this study, an XYθ position sensor is designed/proposed to realize the precise control of the XYθ position of a holonomic inchworm robot in the centimeter to submicrometer range using four optical encoders. The sensor was designed to be sufficiently compact for mounting on a centimeter-sized robot for closed-loop control. To simultaneously measure the XYθ displacements, we designed an integrated two-degrees-of-freedom scale for the four encoders. We also derived a calibration equation to decrease the crosstalk errors among the XYθ axes. To investigate the feasibility of this approach, we placed the scale as a measurement target for a holonomic robot. We demonstrated closed-loop sequence control of a star-shaped trajectory for multiple-step motion in the centimeter to micrometer range. We also demonstrated simultaneous three-axis proportional–integral–derivative control for one-step motion in the micrometer to sub-micrometer range. The close-up trajectories were examined to determine the detailed behavior with sub-micrometer and sub-millidegree resolutions in the MHz measurement cycle. This study is an important step toward wide-range flexible control of precise holonomic robots for various applications in which multiple tools work precisely within the limited space of instruments and microscopes.
Thermal Characterisation of Hybrid, Flip-Chip InP-Si DFB Lasers
Authors: Coenen David , Sar Huseyin , Oprins Herman , Marinins Aleksandrs , De Koninck Yannick , Smyth Stuart , Ban Yoojin , Van Campenhout Joris , De Wolf Ingrid
Published: February 2023

WA detailed thermal analysis of a hybrid, flip-chip InP-Si DFB laser is presented in this work. The lasers were experimentally tested at different operating temperatures, which allowed for deriving their thermal performance characteristics: the temperature dependence of threshold current, lasing slope, and output spectrum. Using these data, the laser thermal resistance was calculated (Rth = 75.9 K/W), which allows for predicting the laser temperature during operation. This metric is also used to validate the thermal finite element models of the laser. A sensitivity study of the laser temperature was performed using these models, and multiple routes for minimising both the laser thermal resistance and thermal coupling to the carrier die are presented. The most effective way of decreasing the laser temperature is the direct attachment of a heat sink on the laser top surface.