A New Variant of Dynamic Pickup and Delivery Problem with Time WindowsPetr Valenta
, Hana Rudová
, Soumen Atta
, 2020, objavljeni znanstveni prispevek na konferenci
Opis: Motivated by the challenges faced by a logistics company, we present a new variant of the dynamic capacitated pickup and delivery problem with time windows (PDPTW) where excessive changes of unaffected routes are undesirable. In real-life scenarios, different dynamism sources such as canceled requests, change of demands, change of pickup, or delivery time windows often disrupt the existing planning of routes. The static PDPTW is solved with the current information about the problem well before executing the routes, such as the previous night. We present an algorithmic idea of a dynamic solver quickly addressing changes that occur due to the dynamism while avoiding excessive modifications to the previous solution. Since the company has not yet the dynamic data, new dynamic instances are generated from the existing static PDPTW instances in the literature. Preliminary results demonstrate that we can quickly incorporate the required changes. Future perspectives of this ongoing work are discussed in the end.
Ključne besede: Dynamic Pickup and Delivery Problem, Time Windows, Heuristic
Objavljeno v RUNG: 17.04.2023; Ogledov: 579; Prenosov: 0
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Maternal and fetal hair cortisol concentrations in beef cattle at deliveryTanja Peric
, Monica Probo
, Antonella Comin
, Maria Cristina Veronesi
, Marta Montillo
, Alberto Prandi
, 2018, objavljeni povzetek znanstvenega prispevka na konferenci
Opis: Hypothalamus-pituitary-adrenal (HPA) axis of both mother and fetus, is one of key mechanisms involved in fetal programming. Cortisol, the end-product of this axis, plays a critical role in regulating fetal and new-born metabolism and development. The aim of the study was to evaluate maternal and fetal cortisol concentrations shortly after delivery on hair samples non-invasively collected. The study was carried out on 11 pairs of beef cows and their calves (calves were 12 because of one case of twins) from the same farm and subjected to the same managerial conditions. Hair from new-born
calves and from their mothers was
collected on the day of birth shaving their withers to the level of the skin. The hair cortisol concentrations (HCC) were determined by RIA as previously described (Peric et al. 2013: J Dairy Sci 96:3023–3027). The results showed that fetal and maternal HCC ranged from 16.11 to 40.43 pg/mg and from 1.88 to 15.73 pg/mg respectively, with fetal and maternal mean ± SE HCC of 23.72 ± 2.21 and 6.40 ± 1.32 pg/mg respectively (p < 0.001). Fetal HCC were on average 3.5 higher than those of mothers but this ratio differed among the pairs. These differences were also found among the twin calves. These results indicate that in beef cows-and-calves pairs, although HCC at delivery were always higher in calves than in cows, the ratio between fetal and maternal HCC differs among pairs, suggesting an individuality in the fetal programming processes that may also rely on genetic and epigenetic factors.
Ključne besede: hair, cortisol, cattle, delivery
Objavljeno v RUNG: 09.04.2019; Ogledov: 3059; Prenosov: 0
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