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This paper describes a practical approach to implement computational steering for problem solving environments (PSEs) by using WBCSim as an example. WBCSim is a Web based simulation system designed to increase the productivity of wood scientists conducting research on wood‐based composites manufacturing processes. WBCSim serves as a prototypical example for the design, construction, and evaluation of small‐scale PSEs.

Various changes have been made to support computational steering across the three layers – client, server, developer – comprising the WBCSim system. A detailed description of the WBCSim system architecture is presented, along with a typical scenario of computational steering usage.

The set of changes and components are: design and add a very simple steering module at the legacy simulation code level, provide a way to monitor simulation execution (alert users when it is time to steer), add an interface to access and visualize simulation results, and perhaps to compare intermediate results across multiple steering attempts. These simple changes and components have a relatively low cost in terms of increasing software complexity.

The novelty lies in designing and implementing a practical approach to enable computational steering capability for PSEs embedded with legacy simulation code.

Extrusion-based digital construction (DC) approaches make it feasible to overcome constraints of conventional construction, namely, high formwork costs, long total construction times, low productivity and geometrical inflexibility. However, to date, no satisfactory solutions for extruding strongly inclined and horizontal elements are available. A wood-starch-composite has been systematically developed as a sustainable support material (SM) for extrusion-based DC.

Material and process-specific requirements were identified for this purpose, and a feasible process chain was developed. A parametric study was conducted to determine the influence of SM composition on its extrusion feasibility and compressive strength. Various compositions with two starch types and two wood particle shapes were tested. New, specific testing methods were developed. Selected compositions were tested using a 3D-printing device to verify extrudability and form stability.

Relationships between material compositions of SM and its rheological and mechanical properties were identified. All mixtures showed sufficient compressive strength in respect of the loading conditions analysed. However, their flow properties varied significantly. A mixture of native maize starch and wood floor was identified as the best variant (compressive strength 2.3 MPa).

Comprehensive investigations of possible process chains, as well as full-scale demonstration and optimisation of the process parameters, were not in the scope of this paper. Such investigations are intended in further studies.

The general applicability of wood-based SM for DC with cement-based construction materials was proved.

The findings offer a novel and promising solution for 3D-printing of non-vertical concrete elements. Experimental setup and material compositions are detailed to ensure reproducibility.

The purpose of this study is to quantify the vertical shrinkage rates and the mechanical strength of three-dimensional (3D) printed parts for a variety of wood-based materials for liquid deposition modeling.

The overall hypothesis was that a well-chosen combination of binders, fibers and fillers could reduce shrinkage in the Z dimension and increase compressive and flexural strength (DIN 52185, 52186). To test this assumption, eight sub-hypotheses were formulated. Mixtures of the ingredients were chosen in different ratios to measure the performance of prints. For time efficiency, an iterative heuristic approach was used – not testing all variations of all variables in even increments, but cutting off lines of testing when mixtures were clearly performing poorly.

The results showed that some mixtures had high dimensional accuracy and strength, while others had neither, and others had one but not the other. Shrinkage of 3D printed objects was mainly caused by water release during drying. An increase of the wood as well as the cement, sand, salt and gypsum content led to reduced vertical shrinkage, which varied between 0 and 23%. Compressive and flexural strength showed mixed trends. An increase in wood and salt content worsened both strength properties. The addition of fibers improved flexural, and the addition of cement improved compression strength. The highest strength values of 14 MPa for compressive and 8 MPa for flexural strength were obtained in the test series with gypsum.

This paper is an important milestone in the development of environmentally friendly materials for additive manufacturing. The potential of many ingredients to improve physical properties could be demonstrated.

The purpose of this review paper is to provide a review of the most recent advances in the field of manufacturing composite sandwich panels along with their advantages and limitations. The other purpose of this paper is to familiarize the researchers with the available developments in manufacturing sandwich structures.

The most recent research articles in the field of manufacturing various composite sandwich structures were reviewed. The review process started by categorizing the available sandwich manufacturing techniques into nine main categories according to the method of production and the equipment used. The review is followed by outlining some automatic production concepts toward composite sandwich automated manufacturing. A brief summary of the sandwich manufacturing techniques is given at the end of this article, with recommendations for future work.

It has been found that several composite sandwich manufacturing techniques were proposed in the literature. The diversity of the manufacturing techniques arises from the variety of the materials as well as the configurations of the final product. Additive manufacturing techniques represent the most recent trend in composite sandwich manufacturing.

This work is valuable for all researchers in the field of composite sandwich structures to keep up with the most recent advancements in this field. Furthermore, this review paper can be considered as a guideline for researchers who are intended to perform further research on composite sandwich structures.

A compressed cycle time enables products to be manufactured more quickly and has the potential of locking in the most profitable customer. Applies time‐based process mapping (TBPM), a time compression technique, to a firm that operates in a resource‐based environment, and undertake detailed case studies. Analyses the firm's key supply chains and examine related strategic issues. Competitive forces analyses indicate that depleting supply, which is valuable, in an attractive industry affects considerably the time horizon of strategy formulation. Robust supply chains integration requires a good consideration of a firm's resources, capabilities and external environments. Both the industrial organisation and resource‐based view are important to sustain business timeliness and operations management. It seems, from the case studies, that in times of intense competition with shortages of resources, continued globalisation, and the fast and slow world divide, the integration of value chains and systems is an effective way of achieving business timeliness. Enabling yet effective strategies and technologies only come to their optimum with proper leadership – the interconnectivity of the time compression triangle.

The purpose of the study was to prepare melamine-urea-formaldehyde (MUF) resin that would be resistant to boiling water and high temperature and exhibit low formaldehyde emission.

The authors prepared MUF resin with different F/(M + U) and changed the amount of melamine added, through the analysis of MUF resin properties to get the best reaction parameters, and used different amino acid cure systems including NH₄Cl cured the resin.

Resin’s heat resistance and water resistance are mainly determined by the amount of melamine added, and formaldehyde emission of the plywood can be changed by adjusting F/(M + U). The peak temperature of the curing agent-cured resin increases as compared with the self-curing resin. Stronger the acidity of curing agent, faster the viscosity increased in probation period and lower the bonding strength and heat resistance of the resin.

Melamine improves the heat resistance and water resistance of the resin. When the amount of melamine is more than a certain value, water resistance of the resin decreased.

MUF resin that is resistant to boiling water and exhibits low formaldehyde emission can be used in high temperature, high humidity and strict formaldehyde emission environment and can also be combined with other materials.

It was helpful to reduce the effect of formaldehyde emission on people’s health and environmental pollution and is also beneficial for the expansion of the application range of aldehyde resin.

The originality is twofold: the influence of the acid strength of curing agent on the bonding strength of the resin adhesive and the method for preparing high performance MUF resin by following the traditional process.

Describes the uses and advantages of perceptual mapping, a consumer‐based modelling technique having both diagnostic and strategic applications, particularly in determining the threat posed by substitute products and in developing competitive strategies. Uses a case study approach of analysing companies in traditional manufacturing industries who are attempting to move from basic commodities to faster growing “value‐added” products. Concludes that perceptual maps are effective in developing new products and product positioning and can be easily used by managers in developing actions.

A water repellent fluorenated monomer was used in a mixture of monomers for treatment of pine wood samples, using both, impregnation and graft copolymerization methods. This resulted in obtaining a new wood‐based material, the properties of which are superior to those of the natural untreated one. The total polymer loading was generally low, but it was sufficient for improving the mechanical properties with an obvious decrease in the water uptake. Better results of bending strength can be obtained on treatment using the graft copolymerization technique, this can be attributed to the chemical bonding of the polymer with cellulose on grafting.

The purpose of this research paper focused on studying the role of activated carbons (ACs), which were synthesized from long-chain aldehyde-based xerogels (Xs-AC), as benefit additives to enhance the application of a low-cost urea formaldehyde (UF) adhesive for production of rice straw (RS) composites complying with both the standard specifications of particle-board type and the board produced from using conventional adhesive of RS fibers (methylene diphenyl diisocyanate, MDI). The results are supported by differential scanning calorimetry (DSC) analysis, which indicated the curing and interaction of RS fibers with the adhesive systems.

RS-based composites of particle-board type were prepared from applying new Xs-AC–UF adhesive systems to RS particles. For comparison, particle boards by using commercial UF and 4 per cent MDI were also prepared. To clear the beneficial effect of X-ACs as new HCHO (formaldehyde)-scavengers, the properties of the resulted boards were compared with those produced from the previous investigated scavenger: amide-containing starch-UF (AM/St–UF), and treated RS. DSC analysis was performed on the RS adhesive system, to follow the curing and the interaction behavior of UF with fibers in the presence of Xs-ACs.

The promising results obtained of RS particle boards from using the investigated new HCHO-scavenger are modulus of rupture (MOR) = 17.2 MPa, modulus of elasticity (MOE) = 4,689 MPa and internal bond (IB) strength = 0.49 MPa. While, the thickness swelling (TS) and maximum reduction in free-HCHO are 48.5 and 44.6 per cent, respectively; this reduction value specified the particle-board of E1-E2 type.

The X-AC-UF adhesive systems and treated RS provided particle boards with mechanical properties (MOR, MOE and IB) that met the standard specification values (class M-2 according to ANSI standard and P-2 according to EN standard requirements), together with maximum reduction in toxicity of UF. However, the resistance in water swelling property is weak and needs further study to be solved.

The incorporation of small percentage of new HCHO-scavenger (X-AC) to UF is an effective way to improve its thermal behavior. Moreover, the mechanical properties of agro-based composites based on the treated RS waste together with the X-AC-UF system exceeded those values of panels produced from (AM/St-UF) and also from (4 per cent MDI).

Incorporating the Xs-AC to commercial UF will be of benefit for saving the health of wood co-workers and motivating the wood mill to export its wood products, as well as minimizing the export of MDI.

This paper was based on enhancing the potential utilization of both undesirable RS agro wastes and environmentally unacceptable low-cost UF adhesive in the production of agro-composites that comply with the International Standard Specifications of particle board type. In this respect, a new HCHO-scavenger was synthesized and applied, based on AC from non-conventional xerogels. This study presents a solution to protect the environment from pollution, as a result of burning the undesirable RS, as well as to protect the workers and users of wood panels from exposure to the toxic and carcinogenic gas (formaldehyde). It also benefits in replacing the high cost of the RS adhesive (MDI) by using low-cost modified UF.

The purpose of this paper is to obtain high-solids-content and low-viscosity starch adhesive, and improve bonding strength of the pure starch adhesive.

Maize starch was treated by hydrochloric acid solution with different concentrations, and acid-thinned starch adhesive was prepared. Polyisocyanate as a crosslinking agent was added to improve water resistance of the pure starch adhesive.

The physical and chemical properties of the acid-thinned starch adhesive were characterised. Acid hydrolysis did not change structure of starch granules, but increased its crystallinity. After acid modification, starch granules became less smooth and some fragments appeared. Acid treatment had little influence on thermal stability of starch, when acid hydrolysis was not strong. High concentration of HCl solution led to starch granules being destroyed, resulting in decrease in bonding strength. The optimal HCl concentration was 0.5 mol/L. Polyisocyanate addition was beneficial to improve the bonding strength of the acid-thinned starch adhesive.

Acid hydrolysis changed the properties of the starch adhesive.

Acid hydrolysis decreased viscosity of the starch adhesive and improved its solids content, which had a positive effect on the application of the starch adhesive.

It was helpful to develop an environment-friendly, natural polymer-based wood adhesive.

The properties of acid-thinned starch and acid-thinned starch adhesive were studied.