Search results for "production [photon]"
showing 10 items of 138 documents
Detection of genomic regions underlying milk production traits in Valle del Belice dairy sheep using regional heritability mapping
2021
The aim of this study was to identify genomic regions underlying milk production traits in the Valle del Belice dairy sheep using regional heritability mapping (RHM). Repeated measurements for milk yield (MY), fat percentage and yield (F% and FY) and protein percentage and yield (P% and PY), collected over a period of six years (2006-2012) on 481 Valle del Belice ewes, were used for the analysis. Animals were genotyped with the Illumina 50k SNP chip. Variance components, heritabilities, and repeatability within and across lactations were estimated, fitting parity, litter size, season of lambing, and fortnights in milk, as fixed; and additive genetic, permanent environment within and across …
Local Capacity $H_{\infty}$ Control for Production Networks of Autonomous Work Systems With Time-Varying Delays
2010
This paper considers the problem of local capacity H∞ control for a class of production networks of autonomous work systems with time-varying delays in the capacity changes. The system under consideration is modeled in a discrete-time singular form. Attention is focused on the design of a controller gain for the local capacity adjustments which maintains the work-in-progress (WIP) in each work system in the vicinity of planned levels and guarantees the asymptotic stability of the system and reduces the effect of the disturbance input on the controlled output to a prescribed level. In terms of a matrix inequality, a sufficient condition for the solvability of this problem is presented using …
Improving Of The Productivity And The Quality Of A Manufacturing Robotized Cell For Mig/Mag Welding
2007
During the last years, globalization and the necessity to reduce production costs have pushed industry to employ more and more manufacturing robotized cells. This trend has been assimilated by arc welding too. The use of robotic systems allows to increase the performance of productive systems by means of reduction in lead-time, reproducibility of processes and increase in quality. However, process automation needs pre-scheduling of manufacturing cell movements and also a setup of different welding parameters, such as power provided by the welding generator, arc length and robot speed, all of which allows to get a joint without defects. An online scheduling of robotic systems brings certainl…
Colon Cancer Stem Cells Dictate Tumor Growth and Resist Cell Death by Production of Interleukin-4
2007
A novel paradigm in tumor biology suggests that cancer growth is driven by stem-like cells within a tumor. Here, we describe the identification and characterization of such cells from colon carcinomas using the stem cell marker CD133 that accounts around 2% of the cells in human colon cancer. The CD133(+) cells grow in vitro as undifferentiated tumor spheroids, and they are both necessary and sufficient to initiate tumor growth in immunodeficient mice. Xenografts resemble the original human tumor maintaining the rare subpopulation of tumorigenic CD133(+) cells. Further analysis revealed that the CD133(+) cells produce and utilize IL-4 to protect themselves from apoptosis. Consistently, trea…
Failures (with some successes) of assisted reproduction and gamete donation programs
2013
Although the possibilities for the treatment of infertility have been improved tremendously, not every couple will be treated successfully.Crude overall pregnancy rates of 50-65% per patient can be achieved nowadays, irrespective of the type of profertility treatment applied first.IVF only accounts for about 20% of the pregnancies achieved. Dropout is an important reason for not reaching the estimated pregnancy rate. Even after failed IVF, spontaneous pregnancies do occur. Sperm and oocyte donation (OD) offer additional chances to subfertile couples. Severity of the male factor (in sperm donation) and young donor age (in OD) are important determinants of success.Analysis of assisted reprodu…
Labour Scheduling at an Airport Refuelling Installation
1999
We have developed an automatic assignment procedure for labour scheduling at a continously operating airport refuelling installation. Different types of workers are subject to different conditions on the shifts they can do (morning, evening or night), shift lengths, days-off, holidays, terms of contract and working hours. The scheduling process is carried out on a weekly basis, but there are mid-term and long-term conditions and objectives which link each week with the preceding and following weeks. Our package uses firstly a tabu search algorithm to find the best schemes of shifts/days-off to be used to cover the requirements. Secondly, an assignment problem is solved to match the schemes …
Influence of short-term aging on mechanical properties and morphology of polymer-modified bitumen with recycled plastics from waste materials
2020
Polymer-modified bitumen (PMB) is bitumen that has been specifically engineered with polymer for providing enhanced performance in service. The aging of bitumen is a main aspect that is able to affect its final performance: during the production phase in a hot mix plant, all the binders experience short-term aging due to the high processing temperature. The same is true during the production of the modified binder, when the polymer is dispersed at high temperature in the bitumen mass. This paper aims at studying the effect of short-term aging when using different types of modifiers such as recycled polymers obtained from waste materials. A 50/70 penetration-grade bitumen has been modified, …
Stochastic Scheduling of Production Orders Under Uncertainty
2017
This paper attempts to solve the problem of searching minimum production order completion time variants by means of stochastic logical structures with all cost curve descent points and corresponding minimum-cost schedules. The analysis presented in this paper considers scheduling of unique and small batch production, predominantly to order, which accounts for changing requirements of the customer, the complexity and long production process makespan including its technical preparation. Scheduling of production order was performed by means of GAN networks and employed the concept of soft relations. The cost/time relation analysis is based on two-node network models using the cost curve. A new…
Data-Driven Pump Scheduling for Cost Minimization in Water Networks
2021
Pumps consume a significant amount of energy in a water distribution network (WDN). With the emergence of dynamic energy cost, the pump scheduling as per user demand is a computationally challenging task. Computing the decision variables of pump scheduling relies over mixed integer optimization (MIO) formulations. However, MIO formulations are NP-hard in general and solving such problems is inefficient in terms of computation time and memory. Moreover, the computational complexity of solving such MIO formulations increases exponentially with the size of the WDN. As an alternative, we propose a data-driven approach to estimate the decision variables of pump scheduling using deep neural netwo…
A hierarchic approach to production planning and scheduling of a flexible manufacturing system
1999
Abstract The paper deals with the problem of improving the machine utilization of a flexible manufacturing cell. Limited tool magazine space of the machines turns out to be a relevant bottleneck. A hierarchic approach for this problem is proposed. At the upper level, sets of parts that can be concurrently processed (batches) are determined. At the lower levels, batches are sequenced, linked, and scheduled. Methods taken from the literature are used for the solution of the latter subproblems, and an original mixed integer programming model is formulated to determine batches. The proposed methods are discussed on the basis of computational experience carried out on real instances.