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A novel architecture for a reconfigurable micro machining cell
There is a growing demand for machine tools that are specifically designed for the manufacture of micro-scale components. Such machine tools are integrated into flexible micro-manufacturing systems. Design objectives for such tools include energy efficiency, small footprint and importantly flexibility, with the ability to easily reconfigure the manufacturing system in response to process requirements and product demands. Such systems find application in medical, photonics, automotive and electronic industries.
In this paper, a new architecture for a reconfigurable micro manufacturing system is presented. The proposed architecture comprises a micro manufacturing cell with the key design feature being a hexagonal-base on which three tool heads can be attached to three of its sides. Each such machine-tool head, or processing module, is able to perform a different manufacturing process. These tool heads are interchangeable, enabling the cell to be configured to process a wide range of components with different materials, dimensions, tolerances and specification. Additional components of the cell include manipulation robots and an automated buffer unit. Such cells can be integrated into a manufacturing system via a modular conveyor belt to transfer parts from one cell to another and into assembly. A key consideration of the architecture is a control system that is also modular and reconfigurable; such that when new processing modules are introduced the control system is aware of the change and adjusts accordingly. Further to this coordination, issues between modules and machining cells are also considered. Other design considerations include work-piece holding and manipulation.
This paper provides an overview of the architecture, the key design and implementation challenges as well as a high level operational performance assessment by means of a discrete event simulation model of the micro factory cell
Coding by Design: GPT-4 empowers Agile Model Driven Development
Generating code from a natural language using Large Language Models (LLMs)
such as ChatGPT, seems groundbreaking. Yet, with more extensive use, it's
evident that this approach has its own limitations. The inherent ambiguity of
natural language presents challenges for complex software designs. Accordingly,
our research offers an Agile Model-Driven Development (MDD) approach that
enhances code auto-generation using OpenAI's GPT-4. Our work emphasizes
"Agility" as a significant contribution to the current MDD method, particularly
when the model undergoes changes or needs deployment in a different programming
language. Thus, we present a case-study showcasing a multi-agent simulation
system of an Unmanned Vehicle Fleet. In the first and second layer of our
approach, we constructed a textual representation of the case-study using
Unified Model Language (UML) diagrams. In the next layer, we introduced two
sets of constraints that minimize model ambiguity. Object Constraints Language
(OCL) is applied to fine-tune the code constructions details, while FIPA
ontology is used to shape communication semantics and protocols. Ultimately,
leveraging GPT-4, our last layer auto-generates code in both Java and Python.
The Java code is deployed within the JADE framework, while the Python code is
deployed in PADE framework. Concluding our research, we engaged in a
comprehensive evaluation of the generated code. From a behavioural standpoint,
the auto-generated code aligned perfectly with the expected UML sequence
diagram. Structurally, we compared the complexity of code derived from UML
diagrams constrained solely by OCL to that influenced by both OCL and
FIPA-ontology. Results indicate that ontology-constrained model produce
inherently more intricate code, but it remains manageable and low-risk for
further testing and maintenance
Study of microRNAs-21/221 as potential breast cancer biomarkers in Egyptian women
microRNAs (miRNAs) play an important role in cancer prognosis. They are small molecules, approximately 17–25 nucleotides in length, and their high stability in human serum supports their use as novel diagnostic biomarkers of cancer and other pathological conditions. In this study, we analyzed the expression patterns of miR-21 and miR-221 in the serum from a total of 100 Egyptian female subjects with breast cancer, fibroadenoma, and healthy control subjects. Using microarray-based expression profiling followed by real-time polymerase chain reaction validation, we compared the levels of the two circulating miRNAs in the serum of patients with breast cancer (n = 50), fibroadenoma (n = 25), and healthy controls (n = 25). The miRNA SNORD68 was chosen as the housekeeping endogenous control. We found that the serum levels of miR-21 and miR-221 were significantly overexpressed in breast cancer patients compared to normal controls and fibroadenoma patients. Receiver Operating Characteristic (ROC) curve analysis revealed that miR-21 has greater potential in discriminating between breast cancer patients and the control group, while miR-221 has greater potential in discriminating between breast cancer and fibroadenoma patients. Classification models using k-Nearest Neighbor (kNN), Naïve Bayes (NB), and Random Forests (RF) were developed using expression levels of both miR-21 and miR-221. Best classification performance was achieved by NB Classification models, reaching 91% of correct classification. Furthermore, relative miR-221 expression was associated with histological tumor grades. Therefore, it may be concluded that both miR-21 and miR-221 can be used to differentiate between breast cancer patients and healthy controls, but that the diagnostic accuracy of serum miR-21 is superior to miR-221 for breast cancer prediction. miR-221 has more diagnostic power in discriminating between breast cancer and fibroadenoma patients. The overexpression of miR-221 has been associated with the breast cancer grade. We also demonstrated that the combined expression of miR-21 and miR-221can be successfully applied as breast cancer biomarkers
Fermentative Gas Production of Different Feeds Collected During Wet and Dry Seasons when Incubated with Rumen Fluid from Timor Deer (Cervus timorensis)
An experiment was done to investigate rumen microbial fermentation of various feeds comonly given to Timor deer (Cervus timorensis) using the in vitro gas production technique. Seven forage feed sample (Sesbania grandiflora, Leucaena leucocephala, Glyricidia sepium, Zea mays, Ipomea aquatica, Pennisetum purpureum, and native grass) collected during dry and wet seasons and three concentrate feed samples (rice bran, copra meal and tofu waste) were dried and ground. The feed sample (200 g) was transferred into incubation syringe which was then added with incubation medium (mixture of rumen fluid and buffer solution). The rumen fluid was collected from 2 Timor deer using a trokar technique. Incubation was run for 72 h, and gas production was read at 2, 4, 6, 12, 24, 48, and 72 h of incubation. Data were fitted to an exponential equation generally used in similar in vitro gas production studies. Results of the study indicated that there was an effect of season on fermentation parameters (values of a, b or c) for the same feed, but this effect was not consistent from one feed to another. From data of total and cummulative gas productions, it was indicated that Zea mays in either dry or wet season showed the highest, while Leucaena leucocephala exhibited the lowest gas production compared to other feeds tested
Study of hardness and tensile strength of Aluminium-7075 percentage varying reinforced with graphite and bagasse-ash composites
Waste sugarcane bagasse-ash and graphite utilizing as reinforcement in fabricating of an aluminium alloy (Al-7075) based matrix hybrid composites. The aluminium matrix hybrid composites have been fabricated by stir-casting method at 750 °C. Casting was developed in circular metal mould having 5 circular slots of diameter of 21 mm and length of 250 mm. Adding bagasse-ash with varying reinforcement of three cases, in first case 2% constant with varying graphite 1%, 3%, and 5%, in second case 4%, and in third case 6% constant with varying same graphite percentage. The effect of the reinforcement has been performed through various mechanical tests. The mechanical properties measuring such as Brinell hardness and tensile strength of both the samples have been prepared as per the ASTM E23 and E8 standards. Results give out that there will be greater effect of reinforcing different bagasse-ash in aluminium alloy matrix hybrid composites. In the third case more enhanced mechanical properties have been achieved as compared to case one and two of bagasse-ash combination. It shows that the selection of bagasse-ash as reinforcement has one of the most significant criteria for the fabrication of aluminium matrix hybrid composites
A framework of criteria for the sustainability assessment of nanoproducts
AbstractNanotechnology applications (nanoproducts) have entered the market or are expected to do so in the near future. Robust and science-based criteria are required to appraise and manage their sustainability. This paper describes the approach used to develop a comprehensive and reliable framework of criteria, which was missing until now, for evaluating the sustainability of nanoproducts. A literature review of the frameworks and tools employed to assess nanoproducts sustainability implications was firstly performed to select an initial set of criteria. A survey of experts in the sustainable nanotechnology domain was then conducted to elicit their knowledge in terms of completeness, reliability and validity of the criteria set. Ranking and correlation analyses completed the research by identifying the parameters of major interest as well as the links and dependencies between them. A total of 54 and 65 experts replied to the pilot and main survey, respectively. The reliability and validity of the criteria was assessed with the responses from both questionnaires, whereas the answers from the main survey were used to calculate the relative index of the criteria as well as their correlations. This research resulted in a framework composed of 68 criteria, which are structured into six main areas: (i) economic performance; (ii) environmental impacts, (iii) environmental risk assessment; (iv) human health risk assessment; (v) social implications and (vi) technical performance. This study helps to broaden the understanding on the identification of criteria for sustainability assessments. It also provides those interested in evaluating nanotechnology implications with the basis for real case studies, possibly by integrating available information with the stakeholders using tools that support decision-making
Suzuki Type Common Fixed Point Theorem For Four Maps Using α - admissible Functions In Partial Ordered Complex Valued Metric Spaces
In this paper, we obtain a Suzuki type unique common fixed point theorem for four self maps using α-admissible function in partial ordered complex valued metric spaces. Also we give an example to illustrate our main theorem
Multi-port, optically addressed RAM
A random access memory addressing system utilizing optical links between memory and the read/write logic circuits comprises addressing circuits including a plurality of light signal sources, a plurality of optical gates including optical detectors associated with the memory cells, and a holographic optical element adapted to reflect and direct the light signals to the desired memory cell locations. More particularly, it is a multi-port, binary computer memory for interfacing with a plurality of computers. There are a plurality of storage cells for containing bits of binary information, the storage cells being disposed at the intersections of a plurality of row conductors and a plurality of column conductors. There is interfacing logic for receiving information from the computers directing access to ones of the storage cells. There are first light sources associated with the interfacing logic for transmitting a first light beam with the access information modulated thereon. First light detectors are associated with the storage cells for receiving the first light beam, for generating an electrical signal containing the access information, and for conducting the electrical signal to the one of the storage cells to which it is directed. There are holographic optical elements for reflecting the first light beam from the first light sources to the first light detectors
Unique common coupled fixed point theorem for four maps in S b -metric spaces
Abstract. In this paper we prove a unique common coupled fixed point theorem for two pairs of w-compatible mappings in S b -metric spaces satisfying a contractive type condition. We furnish an example to support our main theorem. We also give a corollary for Jungck type maps
Non-Standard Intersections of S-Branes in D=11 Supergravity
We construct new intersecting S-brane solutions in 11-dimensional
supergravity which do not have supersymmetric analogs. They are obtained by
letting brane charges to be proportional to each other. Solutions fall into two
categories with respect to whether there is a non-diagonal term to be cancelled
in the field equations or not. In each case we show that they can be
constructed by using a simple set of rules which is similar to the harmonic
function rule of the usual static p-branes. Furthermore, we study an
intersection where the Chern-Simons term makes a non-zero contribution to the
field equations. We show that this configuration has a singularity like other
S-branes.Comment: 13 pages, 2 figures;v2 Section 2.2 is improved with new examples,
references added;v3 typos correcte
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