Composing Vessel Fleets for Maintenance at Offshore Wind Farms by Solving a Dual-Level Stochastic Programming Problem Using GRASP

Background: Dual-level stochastic programming is a technique that allows modelling uncertainty at two different levels, even when the time granularity differs vastly between the levels. In this paper we study the problem of determining the optimal fleet size and mix of vessels performing maintenance operations at offshore wind farms. In this problem the strategic planning spans decades, while operational planning is performed on a day-to-day basis. Since the operational planning level must somehow be taken into account when making strategic plans, and since uncertainty is present at both levels, dual-level stochastic programming is suitable. Methods: We present a heuristic solution method for the problem based on the greedy randomized adaptive search procedure (GRASP). To evaluate the operational costs of a given fleet, a novel fleet deployment heuristic (FDH) is embedded into the GRASP. Results: Computational experiments show that the FDH produces near optimal solutions to the operational day-to-day fleet deployment problem. Comparing the GRASP to exact methods, it produces near optimal solutions for small instances, while significantly improving the primal solutions for larger instances, where the exact methods do not converge. Conclusions: The proposed heuristic is suitable for solving realistic instances, and produces near optimal solution in less than 2 h.

SYNTHESIS OF THE FLEET MANAGEMENT SYSTEM SMALL SHIPPING COMPANY

Within the framework of the methodological support being developed for the planning and management of the fleet of a small shipping company, the task of synthesizing a management system has been solved. The structure and parameters of the system are determined based on the specified requirements for the conditions of its operation, as well as ways to ensure the goals of the functioning of the fleet management system of a small shipping company. The concept of a small, medium or large shipping company is defined by the number of vessels under operational management. It is noted that due to the variability of the economic situation in the transportation market in modern market conditions, permanent "rigid" connections between the elements of the transport system are not formed and the problem of coordinating the work of these elements exists only at the level of operational planning and regulation for small shipping companies. Therefore, it is necessary and sufficient to limit the system under study to the framework of flight planning. The fleet management system at this level in trump shipping traditionally consists of two consecutive subprocesses: the formation of vessel traffic patterns and the assignment of specific vessels to these schemes. The main result of the study is that a new management system structure was formed on the basis of a system analysis of processes in the conditions of working with a small fleet and identified addition-al tasks and requirements for the system. Distinctive features of the new structure from the prototype: the process of arranging transport vessels has been replaced by the process of determining the optimal composition of the leased fleet; two auxiliary subprocesses have been added to manage additional operations if necessary to unload cargo on an unequipped shore.

Cyber-jihad in the Western Balkans

During the last two decades, the growing threat of Islamic terrorism has raised numerous security challenges for both states and non-state actors. Cyberspace is weaponized by actors who conduct malicious activities, in order to achieve their goals. Terrorist organizations reflect the darker side of cyberspace. Terrorists use cyberspace to collect data, raise funds, conduct propaganda, spread radical ideologies and hate speech as well as for the purposes of radicalization, recruitment and operational planning. Social media platforms provide a fertile ground to extend the radical ideologies, to spread terror and to connect with people who share the same views. ISIS is considered a pioneer in utilizing the benefits that cyberspace offers. The Western Balkans is a region where ISIS is recruiting foreign fighters and lone-wolves. The European Union is the driving force for the activation of Western Balkans in countering cyberterrorism and developing relevant strategies.

INVOLVEMENT OF EMPLOYEES IN OPERATIONAL PLANNING OF MANUFACTURING ENTERPRISES: LATVIA EXPERIENCE

The main feature of teamwork is a common goal, and the involvement of employees is essential to its achievement. In a wider scope, it is understood not only by the involvement of employees in decision-making but also as the involvement of employees in operational planning and strategic issues. Research aim is to find out whether the involvement of employees in decision-making, goal setting and planning is inherent in manufacturing enterprises. According to a survey of 268 different level employees of 25 manufacturing enterprises in Latvia, it was found out that involvement of all employees in the decision-making process is not perceived by the enterprises` performance and strategic planning, and the involvement of employees in decision-making and goal setting can only be seen within the department. Keywords: decision-making, employee involvement, goal setting, operational planning, manufacturing enterprise, teamwork

Qualifying the Information Detected from Airborne Laser Scanning to Support Tropical Forest Management Operational Planning

(1) Background: Forests throughout the world are managed to fulfil a range of commercial and ecosystem services. The same applies to managed areas of the Amazon forest. We explore a method of sustainable forest management (SFM) which anticipates the result of processes of natural mortality of large, mature trees that could fall and damage their neighbors. Collecting all the information required for planning logging in the Brazilian Amazon is, currently, a hard, time-consuming and expensive task. (2) Methods: This information can be obtained more quickly, accurately and objectively by including airborne laser scanning (ALS) products in the operational plan. We used ALS point clouds to isolate emergent crowns from the canopy height model. Then, we performed field work to validate the existence of these trees, and to understand how many commercial trees (tree diameter ≥ 50 cm) we identified by orienting the trees search through the emergent canopy model. (3) Results: We were able to detect 184 (54.4%) trees from 338 field-recorded individuals in 20 plots (totaling 8 ha). Of the detected trees, 66 individuals were classified as having potential for commerce. Furthermore, 58 individuals presented the best stem quality for logging, which represents more than seven high quality commercial trees per hectare. The logistic regression showed that the effects that positively influence the emergent crown formation are strongly presented in the commercial species. (4) Conclusions: Using airborne laser scanning can improve the SFM planning in a structurally complex, dense and mixed composition tropical forest by reducing field work in the initial stages of management. Therefore, we propose that ALS operational planning can be used to more efficiently direct field surveys without the need for a full census.