Defect Removal and Rearrangement of Wood Board Based on Genetic Algorithm

Defects on a solid wood board have a great influence on the aesthetics and mechanical properties of the board. After removing the defects, the board is no longer the standard size; manual drawing lines and cutting procedure is time-consuming and laborious; and an optimal solution is not necessarily obtained. Intelligent cutting of the board can be realized using a genetic algorithm. However, the global optimal solution of the whole machining process cannot be obtained by separately considering the sawing and splicing of raw materials. The integrated consideration of wood board cutting and board splicing can improve the utilization rate of the solid wood board. The effective utilization rate of the board with isolated consideration of raw material sawing with standardized dimensions of wood pieces and board splicing is 79.1%, while the shortcut splicing optimization with non-standardized dimensions for the final board has a utilization rate of 88.6% (which improves the utilization rate by 9.5%). In large-scale planning, the use of shortcut splicing optimization also increased the utilization rate by 12.14%. This has certain guiding significance for actual production.

IMPACT OF THE ELECTRIC CABLES INSTALLATION ON THE IGNITION PARAMETERS OF THE SPRUCE WOOD SURFACE

This study is aimed to investigate of an impact of electrical cables installed on Norway spruce (Picea abies(L.) Karst.) wood board surface on main ignition parameters (mainly critical heat flux, ignition temperature, thermal response parameter and thermal inertia). Ignition parameters have been determined by dependence of ignition times (raised to the power of -1, -1/2 and -0.547) on heat flux. Initiation times have been measured for three configurations of spruce wood boards with surface dimensions of 100 x 100 mm ± 1 mm (the first configuration: board without cables on surface, the second configuration: board with three electrical cables on surface -spacing between cables was equal to their diameter and the third configuration: board with five electrical cables -spacing between cables was equal to their diameter) at five heat fluxes (30, 35, 40, 45 and 50 kW·m-2). Obtained results proved that installation of the electrical cables on the spruce wood board surface has a significant impact on the ignition parameters. The critical heat flux (8.5 kW·m-2), apparent thermal inertia0.20 ± 0.02 kJ2·m-4·K-2·s-1and ignition temperature 324 ± 105°C of spruce wood board increased up to 18 ± 3 kW·m-2(critical heat flux), 0.68 ± 0.03 kJ2·m-4·K-2·s-1(apparent thermal inertia) and 475 ± 27°C (ignition temperature) by theinstallation of electrical cableson the surface of spruce wood board.

Preliminary Design Proposals for Dovetail Wood Board Elements in Multi-Story Building Construction

Adhesives and metal fasteners play important roles in the composition and connections of engineered wood products (EWPs) such as cross-laminated timber and glue-laminated timber in the building construction industry. However, due to their petroleum-based nature, adhesives can cause toxic gas emissions, while metal fasteners compromise the end-of-life disposal and reusability of EWPs. These issues adversely affect the sustainable material properties of EWPs. Numerous studies have been conducted in the literature on the technological, ecological, social, and economic aspects of EWPs in construction with different construction solutions, but no studies have been conducted to evaluate the technical performance of dovetail wood board elements (DWBE) in multi-story or tall building construction. This study focuses on adhesive- and metal fastener-free DWBE as sustainable material alternatives for ecologically sensitive engineering solutions. Various preliminary design proposals are presented for DWBE using architectural modeling programs as an environmentally friendly approach intended for use in the timber construction industry. The research findings are based on a theoretical approach that has not yet been practically tested but is proposed considering existing construction practices that need further investigation, including technical performance tests. It is believed that this paper will contribute to the promotion and diffusion of DWBE for more diverse and innovative architectural and structural applications, particularly in multi-story timber building construction, as one of the key tools in tackling climate change challenges.

Solution to Solid Wood Board Cutting Stock Problem

In the production process for wooden furniture, the raw material costs account for more than 50% of furniture costs, and the utilization rate of raw materials depends mainly on the layout scheme. Therefore, a reasonable layout is an important measure to reduce furniture costs. This paper investigates the solid wood board cutting stock problem (CSP) and establishes an optimization model, with the goal of the highest possible utilization rate for original boards. An ant colony-immune genetic algorithm (AC-IGA) is designed to solve this model. The solutions of the ant colony algorithm are used as the initial population of the immune genetic algorithm, and the optimal solution is obtained using the immune genetic algorithm after multiple iterations are transformed into the accumulation of global pheromones, which improves the search ability and ensures the solution quality. The layout process of the solid wood board is abstracted into the construction process of the solution. At the same time, in order to prevent premature convergence, several improved methods, such as a global pheromone hybrid update and adaptive crossover probability, are proposed. Comparative experiments are designed to verify the feasibility and effectiveness of the AC-IGA, and the experimental results show that the AC-IGA has better solution precision and global search ability compared with the ant colony algorithm (ACA), genetic algorithm (GA), grey wolf optimizer (GWO), and polar bear optimization (PBO). The utilization rate increased by more than 2.308%, which provides effective theoretical and methodological support for furniture enterprises to improve economic benefits.

STRESS-STRAINSTATE OF THE FLEXIBLE ELEMENT WITH COMPOSITE UNREMOVABLE FORMWORK

The article deals with the work under load of a bent reinforced concrete girder element with a fixed formwork made of cement-bonded particleboard reinforced with. The main strength and deformation parameters of a multi component structure are determined, the main pre-purpose of which is to use overlap for monolithic structures with the inclusion of non-removable formwork of cement-bonded wood board in collaboration.

Optimal Kiln Dry Allocation for Dry Timber Preparation with Minimal Cost and Available Capacity

Optimization models are increasingly developed for planning and scheduling natural resources manufacture. However, the uncertainty of material from natural resources makes it more difficult to develop a model. In this paper, we concern on the cost of dry timber preparation to finishing sections in a wood-board manufacturer. Based on the characteristic of the material and wood-board production process, we develop two models to a minimize transportation and production cost of wood supply chain which is consist of dry timber preparation process after the sawing process. The models consider facilities capacity, the distance between facilities and drying periods based on timber specification. The model is solved using linear programming, result in drying allocation on the chamber in kiln dry with a minimum cost of the process. A sensitivity analysis is conducted to verify the models and show the effect of variation of two parameters to the objective value. The results show varies of external capacity of kiln dry is more sensitive to total cost than varies of internal capacity.