scholarly journals Metaheuristics for the Minimum Time Cut Path Problem with Different Cutting and Sliding Speeds

Algorithms ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 305
Author(s):  
Bonfim Amaro Amaro Junior ◽  
Marcio Costa Santos ◽  
Guilherme Nepomuceno de Carvalho ◽  
Luiz Jonatã Pires de Araújo ◽  
Placido Rogerio Pinheiro
Keyword(s):  
Real World ◽  
Laser Cutting ◽  
Processing Time ◽  
Minimum Time ◽  
Two Dimensional ◽  
Cutting And Packing ◽  
Commercial Software ◽  
Parameter Values ◽  
Manufacturing Time

The problem of efficiently cutting smaller two-dimensional pieces from a larger surface is recurrent in several manufacturing settings. This problem belongs to the domain of cutting and packing (C&P) problems. This study approached a category of C&P problems called the minimum time cut path (MTCP) problem, which aims to identify a sequence of cutting and sliding movements for the head device to minimize manufacturing time. Both cutting and slide speeds (just moving the head) vary according to equipment, despite their relevance in real-world scenarios. This study applied the MTCP problem on the practical scope and presents two metaheuristics for tackling more significant instances that resemble real-world requirements. The experiments presented in this study utilized parameter values from typical laser cutting machines to assess the feasibility of the proposed methods compared to existing commercial software. The results show that metaheuristic-based solutions are competitive when addressing practical problems, achieving increased performance regarding the processing time for 94% of the instances.

scholarly journals Rapid Formation of Stem Cell Spheroids Using Two-Dimensional MXene Particles

Processes ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 957
Author(s):  
JunHwee Jang ◽  
Eun-Jung Lee
Keyword(s):  
Stem Cell ◽  
Mass Production ◽  
Processing Time ◽  
Activity Levels ◽  
Two Dimensional ◽  
Spheroid Formation ◽  
Cell Spheroids ◽  
Tissue Healing ◽  
Rapid Formation ◽  
Cell Sources

Cell spheroids have been studied as a biomimic medicine for tissue healing using cell sources. Rapid cell spheroid production increases cell survival and activity as well as the efficiency of mass production by reducing processing time. In this study, two-dimensional MXene (Ti3C2) particles were used to form mesenchymal stem cell spheroids, and the optimal MXene concentration, spheroid-production times, and bioactivity levels of spheroid cells during this process were assessed. A MXene concentration range of 1 to 10 μg/mL induced spheroid formation within 6 h. The MXene-induced spheroids exhibited osteogenic-differentiation behavior, with the highest activity levels at a concentration of 5 μg/mL. We report a novel and effective method for the rapid formation of stem cell spheroids using MXene.

scholarly journals Selection of Pairings Reaching Evenly Across the Data (SPREAD): A simple algorithm to design maximally informative fully crossed mating experiments

2014 ◽  
Author(s):  
Kolea Zimmerman ◽  
Daniel Levitis ◽  
Ethan Addicott ◽  
Anne Pringle
Keyword(s):  
Nearest Neighbor ◽  
Simple Algorithm ◽  
Two Dimensional ◽  
Neighbor Distance ◽  
Crossing Experiments ◽  
The Mean ◽  
Parameter Values ◽  
Selection Of ◽  
Novel Algorithm ◽  
Trait Space

We present a novel algorithm for the design of crossing experiments. The algorithm identifies a set of individuals (a ?crossing-set?) from a larger pool of potential crossing-sets by maximizing the diversity of traits of interest, for example, maximizing the range of genetic and geographic distances between individuals included in the crossing-set. To calculate diversity, we use the mean nearest neighbor distance of crosses plotted in trait space. We implement our algorithm on a real dataset ofNeurospora crassastrains, using the genetic and geographic distances between potential crosses as a two-dimensional trait space. In simulated mating experiments, crossing-sets selected by our algorithm provide better estimates of underlying parameter values than randomly chosen crossing-sets.

Analysis of Segmentation Parameters Effect towards Parallel Processing Time on Fuzzy C Means Algorithm

2018 ◽  
Vol 1 (4) ◽  
pp. 99
Author(s):  
Cepi Ramdani ◽  
Indah Soesanti ◽  
Sunu Wibirama
Keyword(s):  
Parallel Processing ◽  
Processing Time ◽  
Color Image ◽  
Clustering Algorithms ◽  
Fuzzy C Means ◽  
Sequential Processing ◽  
Processing Times ◽  
Parameter Values ◽  
Fuzzy C Means Algorithm ◽  
Segmentation Parameters

Fuzzy C Means algorithm or FCM is one of many clustering algorithms that has better accuracy to solve problems related to segmentation. Its application is almost in every aspects of life and many disciplines of science. However, this algorithm has some shortcomings, one of them is the large amount of processing time consumption. This research conducted mainly to do an analysis about the effect of segmentation parameters towards processing time in sequential and parallel. The other goal is to reduce the processing time of segmentation process using parallel approach. Parallel processing applied on Nvidia GeForce GT540M GPU using CUDA v8.0 framework. The experiment conducted on natural RGB color image sized 256x256 and 512x512. The settings of segmentation parameter values were done as follows, weight in range (2-3), number of iteration (50-150), number of cluster (2-8), and error tolerance or epsilon (0.1 – 1e-06). The results obtained by this research as follows, parallel processing time is faster 4.5 times than sequential time with similarity level of image segmentations generated both of processing types is 100%. The influence of segmentation parameter values towards processing times in sequential and parallel can be concluded as follows, the greater value of weight parameter then the sequential processing time becomes short, however it has no effects on parallel processing time. For iteration and cluster parameters, the greater their values will make processing time consuming in sequential and parallel become large. Meanwhile the epsilon parameter has no effect or has an unpredictable tendency on both of processing time.

scholarly journals Harnessing tipping points in complex ecological networks

2019 ◽  
Vol 16 (158) ◽  
pp. 20190345 ◽  
Author(s):  
Junjie Jiang ◽  
Alan Hastings ◽  
Ying-Cheng Lai
Keyword(s):  
Real World ◽  
Management Strategy ◽  
Ecological Networks ◽  
Tipping Point ◽  
Active Management ◽  
Reduced Model ◽  
Tipping Points ◽  
Two Dimensional ◽  
Pollinator Species ◽  
Global Extinction

Complex and nonlinear ecological networks can exhibit a tipping point at which a transition to a global extinction state occurs. Using real-world mutualistic networks of pollinators and plants as prototypical systems and taking into account biological constraints, we develop an ecologically feasible strategy to manage/control the tipping point by maintaining the abundance of a particular pollinator species at a constant level, which essentially removes the hysteresis associated with a tipping point. If conditions are changing so as to approach a tipping point, the management strategy we describe can prevent sudden drastic changes. Additionally, if the system has already moved past a tipping point, we show that a full recovery can occur for reasonable parameter changes only if there is active management of abundance, again due essentially to removal of the hysteresis. This recovery point in the aftermath of a tipping point can be predicted by a universal, two-dimensional reduced model.

2-D AUTOMATIC COMPOSITION OF NODAL VALUES FROM NUMERICAL MODEL USING SCRIPT PROGRAMMING

2013 ◽  
Vol 62 (1) ◽  
Author(s):  
Rudi Heriansyah
Keyword(s):  
Finite Element ◽  
Numerical Modeling ◽  
Numerical Model ◽  
Finite Difference ◽  
Two Dimensional ◽  
Commercial Software ◽  
One Dimensional ◽  
Automatic Composition ◽  
The Individual ◽  
Individual Nodes

There are many commercial software to perform numerical modeling based on finite element (FEM) and finite difference (FDM) methods. It is often a requirement to the designer, that the values of the individual nodes in the numerical model are known. Usually, these softwares provide two methods to achieve this; firstly, by clicking directly onto the nodes of interest and secondly, by saving or exporting the whole nodal values to an external file. The former way is appropriate for models with small number of nodes, but as the number of nodes increases, it is no longer an efficient or effective way. Through the latter method, all nodal values are obtained, however the values are one-dimensional, and in some cases, only certain nodal values are required for presentation. In this paper, an algorithm for automatic composition of nodal values obtained from the second method mentioned above. The composed nodal values will be in two-dimensional form as this is the format used for uniform shaped model (square or rectangular). Since numerical softwares usually have facilities to save the data in a spreadsheet format, the proposed algorithm is implemented in this environment by using spreadsheet script programming.

Vision-Based Sensing in Dynamic Tests

2013 ◽  
Vol 569-570 ◽  
pp. 767-774 ◽  
Author(s):  
Fabio Casciati ◽  
Sara Casciati ◽  
Li Jun Wu
Keyword(s):  
Real World ◽  
Affine Transformation ◽  
Optic Axis ◽  
Two Dimensional ◽  
Structural System ◽  
Dynamic Tests ◽  
Perspective Distortion ◽  
Displacement Sensors ◽  
System Properties ◽  
Contact Displacement

The availability of a suitable data acquisition sensor network is a key implementation issue to link models with real world structures. Non-contact displacement sensors should be preferred since they do not change the system properties. A two-dimensional vision-based displacement measurement sensor is the focus of this contribution. In particular, the perspective distortion introduced by the angle between the optic axis of the camera and the normal to the plane in which the structural system deforms is considered. A two-dimensional affine transformation is utilized to eliminate the distortion from the recorded to the distortion-free image. The results of a laboratory experiment show the potential of the proposed approach.

Approaches to real world two-dimensional cutting problems

Omega ◽  
2014 ◽  
Vol 47 ◽  
pp. 99-115 ◽  
Author(s):  
Enrico Malaguti ◽  
Rosa Medina Durán ◽  
Paolo Toth
Keyword(s):  
Real World ◽  
Two Dimensional ◽  
Cutting Problems

scholarly journals Dispersal Distances for Airborne Spores Based on Deposition Rates and Stochastic Modeling

2007 ◽  
Vol 97 (10) ◽  
pp. 1325-1330 ◽  
Author(s):  
Anders Stockmarr ◽  
Viggo Andreasen ◽  
Hanne Østergård
Keyword(s):  
Fungal Spores ◽  
Two Dimensional ◽  
Airborne Spores ◽  
Modeling Framework ◽  
Deposition Rates ◽  
Spore Release ◽  
Special Cases ◽  
Release Height ◽  
Dispersal Distances ◽  
Parameter Values

A new modeling framework for particle dispersal is explored in the context of the particles being fungal spores dispersed within a field. The model gives rise to both exponentially decreasing and polynomially decreasing two-dimensional densities of deposited fungal spores. We reformulate the model in terms of time to deposition, and show how this concept is equivalent to the deposition rate for fungal spores. Special cases where parameter values for wind and gravitation lead to exponentially or polynomially decreasing densities are discussed, and formulas for one- and two-dimensional densities of deposited spores are given explicitly in terms of parameters for diffusion, wind, gravitation, and spore release height.

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