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Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 611
Author(s):  
Roque Calvo ◽  
Pilar Gil

Collaborative robots are enablers of flexibility in the current dynamic and uncertain manufacturing environment. Decision making on its implementation requires technical feasibility, involving productivity and workforce implications that should be faced in an integrated perspective in processes where many components of different materials are assembled in products of increasing diversity and complexity. This study introduces two new parametric models for collaborative robotics, formulated in order to evaluate the differential cost of assembly (economic dimension) and the differential income from taxes that supports short-term workforce displacement (social dimension) in cobot implementation. Updated techno-economical parameters are selected for assessing feasibility ranges of application in different production scenarios. Next, the influence curves of productivity gain for a feasible implementation of cobot establish thresholds for decision making under both criteria. The results show the need for productivity gains that are significantly lower in high-wage scenarios than in low-wage scenarios; however, in a joint approach, breakeven productivity gain is always higher for the social dimension threshold than for the economic requirement of cost-effective manufacturing, with a higher gap in low-wage cases. The detailed analysis of a real case study of cobot implementation for assembly demonstrates the practical application of models and potential for future research.


2022 ◽  
Author(s):  
Challenger Mishra ◽  
Niklas von Wolff ◽  
Abhinav Tripathi ◽  
Eric Brémond ◽  
Annika Preiss ◽  
...  

Catalytic hydrogenation of esters is a sustainable approach for the production of fine chemicals, and pharmaceutical drugs. However, the efficiency and cost of catalysts are often the bottlenecks in the commercialization of such technologies. The conventional approach of catalyst discovery is based on empiricism that makes the discovery process time-consuming and expensive. There is an urgent need to develop effective approaches to discover efficient catalysts for hydrogenation reactions. We demonstrate here the approach of machine learning for the prediction of out-comes for the catalytic hydrogenation of esters. Our models can predict the reaction yields with high mean accuracies of up to 91% (test set) and suggest that the use of certain chemical descriptors selectively can result in a more accurate model. Furthermore, cata-lysts and some of their corresponding descriptors can also be pre-dicted with mean accuracies of 85%, and >90%, respectively.


Processes ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 139
Author(s):  
Jinfeng Wang ◽  
Wanying Chang ◽  
Jing Xie

In this paper, the electronic expansion valve (EXV) on the single-tube heat exchange experimental platform was used as a research object. Firstly, the EXVs were selected according to the experimental requirements, and the functional parameters were set. Subsequently, the effective opening ranges of the EXVs were determined by manual control, and the control effects of the EXVs installed at the front and back ends of the test section were compared. Finally, by self-tuning and optimizing the best response curves, the proportional and integral coefficients suitable for the experimental platform were obtained; thus, the automatic intelligent control of EXV based on the proportional integral (PI) control algorithm was realized. From setting EXV functional parameters to realizing PI control, an appropriate experimental system-debugging solution for the whole process could be obtained. Based on the solution, the system stability could be improved, and the transition process time could be shortened. Furthermore, the solution also provided a method to guarantee the accuracy of experimental data and could be applied to the debugging of similar experimental systems.


2022 ◽  
Vol 1212 (1) ◽  
pp. 012023
Author(s):  
A V Levina ◽  
A Ya Fedorov ◽  
M I Fedorova

Abstract The problem of e-waste processing and recovery of valuable metals from such waste for the second use is attracting more and more scientists’ attention. Liquid extraction as one of hydrometallurgy steps is a traditional method for the metal recovery. However, application of solvent extraction is not meet the green chemistry principles due to organic solvents. Aqueous two-phase systems based on water-soluble polymers are promising alternative for hazardous organic solvents. In this work the dependencies of Ce(III) and La(III) distribution coefficients from process time and the initial quaternary ammonium base concentration have been achieved. Also, based on the Ce(III) and La(III) extraction isotherms it has been shown that the metals initial concentrations are highly affects the distribution coefficients of studied metals. The possibility of aqueous two-phase system application as a solvent for quaternary ammonium salt for light REE (Ce(III) and La(III)) extraction from water solution has been shown.


2022 ◽  
pp. 287-310
Author(s):  
Rafael Vargas-Bernal

Additive manufacturing is a strategy to produce parts with complex geometries whose process is prohibitive in cost or impossible through subtractive or formative techniques. Research groups are optimizing additive manufacturing processes to improve their performance and reduce the cost of aerospace parts. One of the emerging design techniques is self-assembly which seeks to reduce the number of parts to produce best design practices and rules. Self-assembly represents a comprehensive strategy that improves process time, product quality, cost of materials, and printability. The purpose of this chapter is to review the technological contributions that self-assembly has had in the additive manufacturing of aerospace parts. Future perspectives of the role of self-assembly in additive manufacturing are proposed. According to what was found in this research, self-assembly will facilitate the additive manufacturing of parts in various technological sectors where the manufacture of lightweight parts with high added value and restrictive regulations are required.


PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0262159
Author(s):  
Asami Naito ◽  
Yoshihiko Kiyasu ◽  
Yusaku Akashi ◽  
Akio Sugiyama ◽  
Masashi Michibuchi ◽  
...  

Introduction GENECUBE® is a rapid molecular identification system, and previous studies demonstrated that GENECUBE® HQ SARS-CoV-2 showed excellent analytical performance for the detection of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) with nasopharyngeal samples. However, other respiratory samples have not been evaluated. Methods This prospective comparison between GENECUBE® HQ SARS-CoV-2 and reference real-time reverse transcriptase polymerase chain reaction (RT-PCR) was performed for the detection of SARS-CoV-2 using anterior nasal samples and saliva samples. Additionally, we evaluated a new rapid examination protocol using GENECUBE® HQ SARS-CoV-2 for the detection of SARS-CoV-2 with saliva samples. For the rapid protocol, in the preparation of saliva samples, purification and extraction processes were adjusted, and the total process time was shortened to approximately 35 minutes. Results For 359 anterior nasal samples, the total-, positive-, and negative concordance of the two assays was 99.7% (358/359), 98.1% (51/52), and 100% (307/307), respectively. For saliva samples, the total-, positive-, and negative concordance of the two assays was 99.6% (239/240), 100% (56/56), and 99.5% (183/184), respectively. With the new protocol, total-, positive-, and negative concordance of the two assays was 98.8% (237/240), 100% (56/56), and 98.4% (181/184), respectively. In all discordance cases, SARS-CoV-2 was detected by additional molecular examinations. Conclusion GENECUBE® HQ SARS-CoV-2 provided high analytical performance for the detection of SARS-CoV-2 in anterior nasal samples and saliva samples.


2021 ◽  
Vol 10 (3) ◽  
pp. 100-107
Author(s):  
Risman Risman

Database security is a very important aspect of an information system. A general information is onlyintended for certain groups. Therefore, it is very important for a company to prevent database leakage sothat the information contained in it does not fall to unauthorized people. Cryptographic technique is an alternative solution that can be used in database security. One way to maintain the security of the database is to use encryption techniques. The method used to secure the database is encryption using the ROTI3 and Caesar Cipher methods. Both of these methods have advantages in processing speed. For thisreason, the author will compare the use of the two algorithms above in terms of the encryption and decryption process time


Webology ◽  
2021 ◽  
Vol 18 (2) ◽  
pp. 1379-1391
Author(s):  
Hayder A. Jawdhari ◽  
Alharith A. Abdullah

Blockchain is one of the technologies provided by the global distribution of computing power. Simply put, the blockchain is the digital ledger in which transactions are recorded. It all started with a desire to see a new form of security system for transferring confidential files. It aims to achieve many goals like decreasing the process time for transferring files to the other party, and reducing the overall expenses as the files are only transferred across the blockchain network with no need for the files to be uploaded and downloaded to the drive. More effective applications have the ability to share files via the technology of Blockchain. The great challenge is to build a private blockchain environment to send files and distribute them securely between parties, such as military institutions and others. In this paper, a private blockchain is built to overcome the side of the security through a secured file-sharing network. This private Blockchain can be utilized at various institutions. A high scale of security is obtained through using an important algorithm that takes into consideration a critical part of the field of cryptography to robustly encrypt the files. The latter ensures that no individual except for the receiver has the ability to access the files. As well, a sufficient speed was obtained when transferring the files, as compared to Ethereum with FTP. Finally, smart contracts have been designed to suit the transfer of files between nodes.


2021 ◽  
Vol 10 (2) ◽  
pp. 21-30
Author(s):  
Ahmida ABIODUN ◽  
Olanrewaju LAWAL ◽  
Oyediran OYEBIYI ◽  
Odiete JOSEPH ◽  
Adeyemi ADETORO

Data security is a key aspect of today’s communication trend and growth. Various mechanisms have been developed to achieve this security. One is cryptography, which represents a most effective method of enhancing security and confidentiality of data. In this work, a hybrid based 136bit key algorithm involving a sequential combination of XOR (Exclusive –Or) encryption and AES (Advanced Encryption Standard) algorithm to enhance the security strength is developed. The hybrid algorithm performance is matched with XOR encryption and AES algorithm using encryption and decryption time, throughput of encryption, space complexity and CPU process time.


Minerals ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 36
Author(s):  
Patrycja Kowalik ◽  
Dorota Kopyto ◽  
Mateusz Ciszewski ◽  
Michał Drzazga ◽  
Katarzyna Leszczyńska-Sejda

This work focused on purifying copper electrolytes from a bismuth impurity on a laboratory scale. The electrolyte came from Polish copper electrorefineries with the content of main components, g/dm3: 49.6 Cu, 160 H2SO4. The electrolyte was enriched in bismuth by Bi2O3 addition. Purification of bismuth contamination was carried out using selected agents with adsorbing effects, such as barium hydroxide octahydrate, strontium carbonate, barium carbonate, barium and lead sulfates. The trials were performed until achieving the Bi level—below 0.1 g/dm3. During the experiments, it was noticed that electrolyte purification degree depends on initial Bi concentration in electrolyte, time and temperature, as well as on the type and amount of the bismuth-lowering agent. The most satisfactory results of Bi impurity removal were with additions of barium hydroxide octahydrate, strontium carbonate and barium carbonate to electrolyte at 60 °C for 1 h. These parameters revealed the highest electrolyte purification degree. Bismuth is not removed effectively from electrolytes by barium sulfate or lead sulfate addition. The efficiency of the purification process is much higher when the agents are added to the solution in the form of carbonates or hydroxides. Extending the electrolyte purification process time may cause dissolution of bismuth from the resulting precipitate and increase of bismuth concentration in electrolytes.


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