Hasil untuk "Computer engineering. Computer hardware"

Andrew J. Moodie, Eric Barefoot, Eric Hutton et al.

Abstract. Geomorphologists have more data and computational resources available than ever before. Collaboration between researchers specializing in different modes of inquiry (e.g. numerical, experimental, and field-based) often accelerates impactful scientific insights, but tools to facilitate these collaborations are lacking. In this article, we present four challenges to collaboration in the geomorphology community, and provide a framework that addresses these challenges to enable research utilizing the full extent of data and computational resources available today. We report a component of this framework, a newly developed specification for a shareable data schema called sandsuet. The schema is designed to accommodate most kinds of rasterized geomorphology data, and makes it easy to package, publish, and share those data. Finally, we present possibilities for community development of resources to address other challenges to collaboration in geomorphology.

Mmabyalwa R. Sebola, Charmain T. Maqhiza, Baraka C. Sempunga et al.

The use of lignocellulose biomass is crucial in biofuel production, to enhance global energy security and avoid food shortages. Feedstock selection of this type of biomass depends on factors such as cellulose, hemicellulose, lignin content, sustainability, quantity, and availability. As such, a good understanding of chemical attributes is crucial for potential energy conversion. Before characterization, the grass was ground and sieved to 0.6 mm for uniformity. The Vetiver grass (VG) was then analyzed through proximate, ultimate, SEM, FTIR, and lignocellulosic characteristics analysis. The VG had 7.63 % moisture content, 4.46 % ash, 69.10 % volatile matter, and 18.81 % fixed carbon. The ultimate analysis showed that the C, H, O, N, and S content was 42.28 %, 5.54 %, 51.54 %, 0.64 %, and 0 %, respectively. Compared to Napier grass, cow dung, and sugar cane bagasse, VG had lower nitrogen and no sulfur with an empirical formula of CH1.6O0.92. The treated VG sample showed increased intensity in the FTIR peak at 1037 cm-1 and additional peaks at 2341 cm-1. Broadening of the peak at 3332 cm-1 indicated improved availability of cellulose and hemicellulose for methane production due to mechanical treatment. The SEM analysis showed the removal of the link between the hemicellulose, cellulose, and lignin cross-linking structure. These results suggest that VG could be a promising bioenergy source.

José R. C. Piqueira, Pedro Augusto Yi Wei Lee, Isabelle Coelho Franco

Clock distribution systems are used in many applications requiring accurate time basis: integrated circuits, computer networks, satellite communications, and Global Position System (GPS). Trying to automatize the design of clock distribution systems, this work presents a general formulation considering the possible topologies and parameters, building a computational tool allowing to design and evaluate the performance of any case to be studied. The developed tool enables to simulate networks setting the number of nodes, internal node parameters, topology, perturbations, and signal propagation delays. The simulation results include response times, synchronization quality, and stability for all types of arrangements: mutually connected, chains, rings, stars, and mixed architectures.

Yongzhi Li, Pengle Zhang, Meng Sun et al.

Background: Document images such as statistical reports and scientific journals are widely used in information technology. Accurate detection of table areas in document images is an essential prerequisite for tasks such as information extraction. However, because of the diversity in the shapes and sizes of tables, existing table detection methods adapted from general object detection algorithms, have not yet achieved satisfactory results. Incorrect detection results might lead to the loss of critical information. Methods: Therefore, we propose a novel end-to-end trainable deep network combined with a self-supervised pretraining transformer for feature extraction to minimize incorrect detections. To better deal with table areas of different shapes and sizes, we added a dual-branch context content attention module (DCCAM) to high-dimensional features to extract context content information, thereby enhancing the network's ability to learn shape features. For feature fusion at different scales, we replaced the original 3×3 convolution with a multilayer residual module, which contains enhanced gradient flow information to improve the feature representation and extraction capability. Results: We evaluated our method on public document datasets and compared it with previous methods, which achieved state-of-the-art results in terms of evaluation metrics such as recall and F1-score. https://github.com/YongZ-Lee/TD-DCCAM

Quynh Gia Ho, Loc Tan Bui, Phuong Thi Truc Nguyen et al.

In this study, mesoporous zeolite ZSM-5 samples were successfully synthesized using the microwave method, and thermal method to evaluate the efficiency of the n-heptane cracking reaction. The physicochemical properties and characteristics of the catalysts were determined by X-ray diffraction (XRD), N2 adsorption-desorption at low temperatures, and scanning electron microscopy (SEM). The effects of the n-heptane cracking reaction temperature of the modified zeolite samples between 400 and 600 °C were investigated. As a result, the mesoporous zeolites were successfully prepared, with the external area of modified zeolites increasing 12-13 times for samples with a high Si/Al ratio and increasing 1.4-3 times for materials with a low Si/Al ratio compared with the original zeolites. For zeolite ZSM-5 with a high Si/Al ratio, the microwave approach successfully modified the initial sample in 12 times less time than the hydrothermal method to obtain approximately the same mesopore surface area. The prepared zeolites with a low Si/Al ratio exhibited higher efficiency than the initial sample in the n-heptane cracking procedure, with the conversion efficiency of the former being 4.4-5.2 % higher than that of the latter.

Hongjian Wang

With the development of the economy and real-time embedded systems and the progress of science and technology, people’s economic income forms have undergone tremendous changes, and the concept of financial management has become clearer in people’s property income arrangements. Project investment is one of the most popular financial management methods in the era of big data. Both large enterprise groups and individual petty bourgeoisie groups have begun to pay attention to the risks and benefits brought by the new financial management method of project investment. This paper’s goal is to develop a fuzzy comprehensive evaluation (FCE) model for project investment risk based on computer vision technology and explore the application of computer vision technology in project investment risk evaluation. This article first uses a real-time embedded system to understand the basic process of project investment and select 10 investment experts for risk assessment, risks, and causes of the risks through literature research and case analysis. Then, this paper establishes a model of fuzzy comprehensive evaluation of project investment risk through computer vision technology, real-time embedded systems, and neural network models in big data and artificial intelligence technology to realize the analysis and prediction of project investment risk. The fuzzy comprehensive evaluation method and analytic hierarchy process (AHP) are used in this evaluation model to evaluate and forecast project investment risks. In addition, this paper also trains and tests the risk evaluation model of this research through the support vector machine classification algorithm, the real-time embedded system, and the average random consistency index. The research shows that the fuzzy comprehensive evaluation model of this study has higher accuracy for project investment risk evaluation than other risk evaluation methods. For example, for the investment risk of chemical fiber projects, this research model evaluated the factors such as organization, management, technology, and economy and found that the risks were all higher than 21.36%, which concluded that the overall investment risk of chemical fiber projects was relatively high.

Jefferson Osorio-Carlozama, Joe Llerena-Izquierdo

Václav Miklas, Michal Touš, Marta Miklasová et al.

The water footprint of wineries is typically more than 1 L water/L wine. In the European context, this annually equals to over a hundred million hectoliters of water, most of which eventually become wastewater. The winery wastewater is known to have high organic loads, most frequently quantified by chemical oxygen demand (COD). Particularly during the vintage season, the discharge of winery wastewater with extreme COD values can paralyze municipal wastewater treatment plants. As a result, the treatment plants pose strict limits on wastewater parameters. This forces wineries to either transport the wastewater to specialized facilities capable of handling the wastewater extremities, or invest into their own wastewater treatment plant. Since wine has been historically produced by small wineries, either option economically challenge these often family-owned companies. This work reflects the need for robust wastewater treatment technologies that would be able to handle winery wastewater parameters’ fluctuations throughout the year and the abovementioned peaks. The technologies are categorized into physicochemical, biological, membrane, advanced oxidation and combined processes. There are a number of treatment methods that have shown a COD removal rate of over 90 %. However, they significantly vary in size, process flexibility and maintenance difficulty. Some alternative processes are also critically evaluated in the context of circular economy and water reuse, which can further improve the process economy for small- and medium-sized wineries.

Ying Zhan, Austin Fergusson, Lacey R. McNally et al.

Bacteria‐mediated drug delivery systems comprising nanotherapeutics conjugated onto bacteria synergistically augment the efficacy of both therapeutic modalities in cancer therapy. Nanocarriers preserve therapeutics’ bioavailability and reduce systemic toxicity, while bacteria selectively colonize the cancerous tissue, impart intrinsic and immune‐mediated antitumor effects, and propel nanotherapeutics interstitially. The optimal bacteria–nanoparticle (NP) conjugates will carry the maximal NP load with minimal motility speed hindrance for effective interstitial distribution. Furthermore, a well‐defined and repeatable NP attachment density distribution is crucial to determining these biohybrid systems’ efficacious dosage and robust performance. Herein, our nanoscale bacteria‐enabled autonomous delivery system (NanoBEADS) platform is utilized to investigate the effects of assembly process parameters of mixing method, volume, and duration on NP attachment density and repeatability. The effect of linkage chemistry and NP size on NP attachment density, viability, growth rate, and motility of NanoBEADS is also evaluated. It is shown that the linkage chemistry impacts NP attachment density while the self‐assembly process parameters affect the repeatability and, to a lesser extent, attachment density. Lastly, the attachment density affects NanoBEADS’ growth rate and motility in an NP size‐dependent manner. These findings will contribute to the development of scalable and repeatable bacteria–NP biohybrids for applications in drug delivery and beyond. An interactive preprint version of the article can be found here: https://www.authorea.com/doi/full/10.22541/au.163100509.93917936.

Mariela Medina Mori, Haydee Suarez Alvites, Rosario del Pilar Lopez Padilla et al.

Bioelectrogenesis allows the transformation of chemical energy into electrical energy by means of microbial fuel cells.The research aimed to determine the amount of energy generated by bioelectrogenesis using Pseudomonas aeruginosa and Aeromonas hydrophila bacteria. Four double chamber H-type glass microbial fuel cells with a capacity of 500 mL and 2 control cells were constructed, using graphite or aluminium rod electrodes at the anode and graphite rod at the cathode for all the cells. 325 mL of anaerobic sludge and 75 mL of wastewater from a wastewater treatment plant were inoculated as substrate for the bacteria in the anode, where 50 mL of the aforementioned bacteria strain were inoculated, respectively. The experimental part was carried out in 20 days; the conditions of the cells were evaluated in terms of temperature and pH, characteristics of the bacteria and the behaviour of the voltage generated. It was established that the bacteria that generated the highest voltage was Pseudomonas aeruginosa with 0.8960V, using an aluminum electrode in the anode chamber. The results indicate that bioelectrogenesis using bacteria in anaerobic sludge and wastewater is a promising technology for obtaining clean and low-cost energy.

PARK, Y.-S.

This paper deals with the comparison and performance evaluation of a wound rotor synchronous motor (WRSM) and an interior permanent magnet synchronous motor (IPMSM) based on electromagnetic field characteristic analysis. The models have identical stator structure with three-phase coil winding while the rotor outer diameter and stack length are under same condition. Based on surface response method, each model is optimized with applying rotor offset for the improvement of torque quality such as cogging torque and torque ripple. Furthermore, the electromagnetic power losses are analyzed, and their performance is comparatively evaluated. For the verification of analysis results, the IPMSM is manufactured, and its performance evaluation is also presented based on power loss and efficiency maps.

Aleteia Araujo, Ana Júlia Luziano Briceño, Ana Sofia S. Silvestre et al.

There are great female personalities in the history of computing who have played an important role in the historical achievements of this area. However, their contributions are often poorly publicized and/or credit for those contributions is denied to the true authors. Thus, this paper proposes a game called Mundo Bit Byte, created by a team of female undergraduates and high school girls. The story is based on five prominent female personalities in the field of Computing. Each phase of the game is inspired by the life of one of these women, showing, in a playful and fun way, their achievements and other relevant aspects of their lives. A demo version of the game containing two phases was evaluated by 511 people. In the first test, 234 responses were obtained, and in the second test, 277. Most respondents (97.4% in first test and 98.2% in second one) reported that they would like to meet other important women in computing after playing Mundo Bit Byte. The results indicated that games like this can be powerful tools to reduce stereotypes in the Computing area.

Lidia Verano Naranjo, Cristina Cejudo-Bastante, Lourdes Casas et al.

The manufacture of functionalized bioabsorbable polymeric implants is gaining attention in recent years. These devices administer gradually and locally drugs or biomolecules to treat several diseases and they disappear once they perform their function. In this work, ketoprofen, an anti-inflammatory drug with analgesic and antipyretic effects, was loaded by supercritical solvent impregnation (SSI) in polylactic acid (PLA) filaments, and the initial stage of its in vitro release was explored. Impregnation experiments were carried out in a range of pressure and temperature of 25-40 MPa and 328-348 K. Different drug loading values were obtained (up to 9 % respecting the polymer mass) depending on the operating conditions.The ketoprofen release profile and the mathematical modelling (Korsmeyer-Peppas and Peppas-Sahlin models) showed an initial release governed by diffusion and with different kinetics depending on the impregnation conditions. Thus, this study reveals that SSI could be used to manufacture personalized drug-delivery implants based on the final dose and required dosing rate.

Ken Matsubara, Daiki Tachibana, Ryosuke Matsuda et al.

Hydrogel actuators, comprising gels that convert external stimuli into mechanical motion for actuation, are attracting attention for their promising applications, such as in robotics. The driving force is the absorption or release of water or another solvent, which results in swelling and shrinking motions, leading in turn to more complex functionalities. However, practical hydrogel actuators that can be controlled locally, such as ones that allow local actuation around the joints in rigid‐bodied robots, do not exist. Herein, the driving target of a thermo‐responsive hydrogel, poly(N‐isopropyl acrylamide), is integrated with the stimulation module using a liquid metal. The stimulation module provides heat as an external stimulus to the hydrogel actuator. The motion of the actuator is triggered by the heat supplied by an ultrasoft hydrogel coil, with liquid metal surrounding the driving target. The heat generated by current flowing through the liquid metal changes the temperature only around the desired part of the actuator, which enables the electrical control of an individual part of the hydrogel actuator. The concept of integrating the driving target and stimulator is expected to facilitate functional movement of actuators and expand the range of potential applications of hydrogels.

Aynaran Oliveira De Aguiar, Debora Dos Santos Rodrigues, Adriana Regia Sousa et al.

Several Cerrado’s fruits with economic potential are consumed in natura or processed around the country, however, few data are available in the specialized literature regarding the chemical composition of these fruits and its technological application. Due to this, there is a need for scientific research on these cerrado´s fruits and its functional value. In the food industry, the juices production and other productions that use fruits as raw material generate a significant residue amount, which have technological and nutritional potential. Because of thatthe objective of this present work was to characterize Araticum fruit (Annona crassiflora Mart.), as well as optimazing the this fruit process in the form of Araticum preserve, using passion fruit´s albedo, discarded as waste by the industry, as a source of pectin. For characterization, moisture analysis, total soluble solids, titratable total acidity, vitamin C, lipid content, protein, total dietary fiber, reducing and non-reducing sugars and antioxidant activity were carried out by the DPPH method. For processing, were used a 2³ factorial design complete with three center points. The Araticum, presented low acidity, soluble solids at about 24 °Brix and  moisture of 60%. The value of ascorbic acid found for the fruit was 58.11 mg /100 g of fruit, whereas the lipid content found in Araticum was 2.83%, that is, they are not fruits with a high fat content for a low calorie diet. The antioxidant activity was 27.19 mg of DPPH/g of fruit. During the optimization, it was observed that the best formulations, in terms of obtaining Araticum preserve with higher concentrations of protein, vitamin C, fibers, and of higher yield are those with high concentration of citric acid and the higher pulp/sugar ratio. Keywords: Cerrado, Araticum, New Product, optimization.

A. S. AlSanabani, M. A. Al-Awlaqi

This study aims to unravel the factors that might have the potential to facilitate or hinder the Enterprise Resource Planning (ERP) system in the Yemen Organizations. Methods were done by interviewing 197 respondents from some Yemen organizations. The results of this study found significant positive correlationsbetween the intention to use and easiness of the ERP system. Several dependent variables were also obtained. Moreover, thecurrent study obtained the importance of human factors in thecontext of ERP.

Syaza Izyanni Ahmad, Nor Alafiza Yunus, Haslenda Hashim et al.

Solvent extraction is a method implemented with the purpose to recover the remaining oil in spent bleaching earth. n-hexane is the most commonly used solvent in solvent extraction due to its advantages such as able to easily extract the oil and can be separated easily with low chances to form emulsions during the extraction process. Although n-hexane is a good solvent for extraction, n-hexane can easily vaporise to the surroundings due to its volatility making it a threat to human health and environment due to its high toxicity and high flammability characteristics. N-hexane should be replaced with greener solvents in term of safety and environmental impacts. This paper aims to evaluate the inherent safety of the solvents designed by the previous work involving three new solvents which are cyclohexane, 2-pentanone and isopropyl acetate and compare it with the existing solvent which is n-hexane. The inherent safety assessment of these solvent were done using the Numerical Descriptive Inherent Safety (NuDIST) technique. In this technique, scores are assigned to each solvent according to their inherent safety level in term of three parameters. The parameters involved are flammability, explosiveness and toxicity. In NuDIST, higher scores indicate higher hazard and is not preferable compared to lower scores. According to the assessment done, cyclohexane is the least hazardous solvent with CSTS of 191.53 while n-hexane is evaluated as the most hazardous solvent with CSTS of 198.32. Inherent safety assessment done between cyclohexane and n-hexane using the NuDIST method indicates cyclohexane as the inherently safer choice than n-hexane. This further supports the result produced by the previous work which indicates cyclohexane as having more promising properties as a solvent in order to extract palm oil in spent bleaching earth compared to n-hexane.

Shuoxin Lin, Yanzhou Liu, Kyunghun Lee et al.

Hoi-Kwan Lau, M. Plenio

Implementing a qubit quantum computer in continuous-variable systems conventionally requires the engineering of specific interactions according to the encoding basis states. In this work, we present a unified formalism to conduct universal quantum computation with a fixed set of operations but arbitrary encoding. By storing a qubit in the parity of two or four qumodes, all computing processes can be implemented by basis state preparations, continuous-variable exponential-swap operations, and swap tests. Our formalism inherits the advantages that the quantum information is decoupled from collective noise, and logical qubits with different encodings can be brought to interact without decoding. We also propose a possible implementation of the required operations by using interactions that are available in a variety of continuous-variable systems. Our work separates the "hardware" problem of engineering quantum-computing-universal interactions, from the "software" problem of designing encodings for specific purposes. The development of quantum computer architecture could hence be simplified.

G. Balia, M. Grosso, S. Tronci et al.

This work focuses on the experimental study about the influence of microwave radiation (at 2.45 GHz of frequency) on the enzyme catalyzed hydrolysis of sucrose in aqueous solutions, in order to detect possible modifications in the whole reaction rate, and to identify the inhibition effect due to sucrose and/or to the hydrolysis product D-fructose. For comparison purposes, the same experimental conditions were applied both in the presence and in the absence of irradiation. The experimental concentrations were estimated from spectrophotometer acquisitions in the UV wavelengths, and data were fitted with proper kinetic models, taking into account the main reaction pathway and inhibition phenomena. The obtained results show a modification in the reaction kinetics due to the microwave application.