Search results for "modeling"
showing 10 items of 4489 documents
Burnout-related ill-being at work : Associations between mindfulness and acceptance skills, worksite factors, and experienced well-being in life
2018
The aim of this paper was to investigate the associations between mindfulness and acceptance (MAA) skills and burnout-related ill-being at work (ILLB) after eliminating the impact of worksite (WS) and general well-being in life (WELLB) factors. The results were derived from data on employees (n = 168) of varying professional backgrounds, who experienced relatively high levels of burnout. Analyses were conducted using structural equation modelling (SEM) and the Cholesky decomposition method, since these allow for the investigation of multiple measures and multiple factors in relation to one another. In relation to ill-being at work, the analyses revealed a general MAA factor as well as a spe…
Structure of Arabic Scale of Death Anxiety With Chinese College Students: A Bifactor Approach
2018
The Arabic Scale of Death Anxiety (ASDA), as one of the most widely used measures of death anxiety (DA), has increasingly been applied in many studies. However, the structures derived from different studies are highly inconsistent. In this study, both traditional and novel (bifactor) modeling approaches were used, to investigate the most optimal structure of the ASDA in a sample of 984 Chinese college students. After a series of comparisons, the results showed that the bifactor model, with a dominant general DA factor and three distinct sub-dimensions, was the most optimal measurement structure, and measurement invariance of this bifactor model between sexes was also confirmed. Based on the…
The Italian Version of the Inventory of Interpersonal Problems (IIP-32): Psychometric Properties and Factor Structure in Clinical and Non-clinical Gr…
2018
All versions of the Inventory of Interpersonal Problems (IIP) are broadly used to measure people's interpersonal functioning. The aims of the current study are: (a) to examine the psychometric properties and factor structure of the Italian version of the Inventory of Interpersonal Problems-short version (IIP-32); and (b) to evaluate its associations with core symptoms of different eating disorders. One thousand two hundred and twenty three participants (n = 623 non-clinical and n = 600 clinical participants with eating disorders and obesity) filled out the Inventory of Interpersonal Problems-short version (IIP-32) along with measures of self-esteem (Rosenberg Self-Esteem Scale, RSES), psych…
Automatic Identification System data - potential resource for marine vessels drift studies in the Baltic Sea
2020
Automatic Identification System (AIS) has been employed for increasing the safety at the sea. Nowadays general information about the marine traffic can be tracked in operational mode using www.marinetraffic.com web portal. Additional information can be purchased for commercial and research purposes. Our study highlights a possibility to study the drift using an additional information available at www.marinetraffic.com - selected data on vessel position during its status “not under command”, which corresponds to the drifting vessels. Trajectories of the drift from AIS have been compared with mathematically modeled point-wise drifter paths. Copernicus Marine Environmental Monitoring Service's…
Some personal views on the current state and the future of locational analysis
1998
In this paper a group of participants of the 12th European Summer Institute which took place in Tenerife, Spain in June 1995 present their views on the state of the art and the future trends in Locational Analysis. The issues discussed include modeling aspects in discrete Location Theory, the influence of the distance function, the relation between discrete, network and continuous location, heuristic techniques, the state of technology and undesirable facility location. Some general questions are stated regarding the applicability of location models, promising research directions and the way technology affects the development of solution techniques.
On the Objective Evaluation of Motion Cueing in Vehicle Simulations
2021
Motion-based simulators are used for a variety of applications, such as research, education, entertainment and training. In fact, motion cues are required to achieve the highest regulatory certifications in training vehicle simulators. Nonetheless, the reproduction of self-motion cues presents technological and economic limitations that are not present in the generation of audiovisual cues. For this reason, the generated motion does not generally match the expected one. Therefore, it is necessary to define means to assess the suitability/fidelity of the generated motion cues. After more than 50 years of motion-based vehicle simulation, no mechanism has been universally accepted as the stand…
Heuristics for the capacitated modular hub location problem
2017
Abstract In this paper we study the hub location problem, where the goal is to identify an optimal subset of facilities (hubs) to minimize the transportation cost while satisfying certain capacity constraints. In particular, we target the single assignment version, in which each node in the transportation network is assigned to only one hub to route its traffic. We consider here a realistic variant introduced previously, in which the capacity of edges between hubs is increased in a modular way. This reflects the practical situation in air traffic where the number of flights between two locations implies a capacity in terms of number of passengers. Then, the capacity can be increased in a mo…
Exact solution of the soft-clustered vehicle-routing problem
2020
Abstract The soft-clustered vehicle-routing problem (SoftCluVRP) extends the classical capacitated vehicle-routing problem by one additional constraint: The customers are partitioned into clusters and feasible routes must respect the soft-cluster constraint, that is, all customers of the same cluster must be served by the same vehicle. In this article, we design and analyze different branch-and-price algorithms for the exact solution of the SoftCluVRP. The algorithms differ in the way the column-generation subproblem, a variant of the shortest-path problem with resource constraints (SPPRC), is solved. The standard approach for SPPRCs is based on dynamic-programming labeling algorithms. We s…
Branch-price-and-cut algorithms for the pickup and delivery problem with time windows and multiple stacks
2016
Abstract This paper proposes models and algorithms for the pickup and delivery vehicle routing problem with time windows and multiple stacks. Each stack is rear-loaded and is operated in a last-in-first-out (LIFO) fashion, meaning that when an item is picked up, it is positioned at the rear of a stack. An item can only be delivered if it is in that position. This problem arises in the transportation of heavy or dangerous material where unnecessary handling should be avoided, such as in the transportation of cars between car dealers and the transportation of livestock from farms to slaughterhouses. To solve this problem, we propose two different branch-price-and-cut algorithms. The first sol…
Solving a large cutting problem in the glass manufacturing industry
2020
Abstract The glass cutting problem proposed by Saint Gobain for the 2018 ROADEF challenge includes some specific constraints that prevent the direct application of procedures developed for the standard cutting problem. On the one hand, the sheets to be cut have defects that make them unique and they must be used in a given order. On the other hand, pieces are grouped in stacks and the pieces in each stack must be cut in order. There are also some additional characteristics due to the technology being used, especially the requirement for a three-stage guillotine cutting process. Taking into account the sequencing constraints on sheets and pieces, we have developed a beam search algorithm, us…