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The purpose of this paper is to present a numerical model of coupled heat, moisture transfer and their effects on the mechanical deformations of wood during the drying process.

Coupling among heat, moisture, and mechanical deformations is solved consecutively by use of sparse solver of MATLAB. The weighted residual of the equilibrium equations of drying process of wood, based on finite element method, is investigated. The stress and plastic strain increments can be solved with Newton's method.

The numerical model is applied to a plain strain problem of a long wood board taken from the outer region of the wood log. Numerical simulation reveals the stress reversal during the drying process. The mechanical deformations and the principle stresses of a three‐dimensional wood board in consideration of the orthotropic properties are presented.

Plane strain and plane stress are analysed. The tangential modulus is derived. The transformation of the stress and strain tensors between the local coordinate system resulting from the cylindrical properties of wood and the global one is evaluated. Selection of element type for temperature, moisture content and displacement is discussed.

At present, piezoelectric impedance technology has been used in the study of wood damage monitoring. However, little effort has been made in the research on the application of piezoelectric impedance system to monitor the change of wood moisture content (MC). The monitoring method of wood MC is used by piezoelectric impedance technique in this study.

One piezoceramic transducer is bonded to the surface of wood specimens. The MC of the wood specimens increases gradually from 0% to 60% with 10% increments; the mechanical impedance of the wood specimen will change, and the change in the mechanical impedance of the structure is reflected by monitoring the change in the electrical impedance of lead zirconate titanate. Therefore, this paper investigates the relationship between wood MC change and piezoelectric impedance change to verify the feasibility of the piezoelectric impedance method for monitoring wood MC change.

The experiment verified that the real part of impedance of the wood increased with the increase of wood MC. Besides, the damage index root mean square deviation is introduced to quantify the damage degree of wood under different MC. At the same time, the feasibility and validity of this experiment were verified from the side by finite element simulation. Finally, MC monitoring by piezoelectric impedance technique is feasible.

To the best of the authors’ knowledge, this work is the first to apply piezoelectric ceramics to the monitoring of wood MC, which provides a theoretical basis for the follow-up study of a wide range of wood components and even wood structure MC changes.

An existing two‐dimensional finite volume technique is modified by introducing a correction term to increase the accuracy of the method to second order. It is well known that the accuracy of the finite volume method strongly depends on the order of the approximation of the flux term at the control volume (CV) faces. For highly orthotropic and anisotropic media, first order approximations produce inaccurate simulation results, which motivates the need for better estimates of the flux expression. In this article, a new approach to approximate the flux term at the CV face is presented. The discretisation involves a decomposition of the flux and an improved least squares approximation technique to calculate the derivatives of the dependent function on the CV faces for estimating both the cross diffusion term and a correction for the primary flux term. The advantage of this method is that any arbitrary unstructured mesh can be used to implement the technique without considering the shapes of the mesh elements. It was found that the numerical results well matched the available exact solution for a representative transport equation in highly orthotropic media and the benchmark solutions obtained on a fine mesh for anisotropic media. Previously proposed CV techniques are compared with the new method to highlight its accuracy for different unstructured meshes.

This study aims to apply a Lean Six Sigma framework to support continuous improvement in the maritime industry (shipbuilding, logistics services and shipping companies) during COVID-19 pandemics. By applying the concepts of Lean Six Sigma and supply chain resilience, the most suitable continuous improvement method for the maritime industry is developed to maintain a resilient supply chain during COVID-19.

A specific shipbuilding, logistics services and shipping company in Indonesia is chosen as the research object. The Lean Six Sigma framework reveals the wastes through the supply chain resilience concept, and implements internal business processes to maintain optimal system performance.

The paper identifies important implementation aspects in applying Lean Six Sigma to shipbuilding, logistics services and shipping. The DMAIC (define, measure, analyze, improve and control) approach is applied to achieve supply chain resilience. Resilient measures are generated for the case companies to maximize performance during the pandemics.

This paper provides a new insight for integrating Lean Six Sigma and resilience strategies in the maritime industry during COVID-19 disruptions. The authors provide some insights to sustain the performance of the maritime industries under study.

This study is part of the first research in the maritime industry that focuses on continuous improvement during COVID-19 using Lean Six Sigma and supply chain resilience.

Study in supply chain performance research on the shipbuilding industry is lacking. The purpose of this research is to study and provide guidelines to improve the performance of traditional shipbuilding supply chains in Indonesia.

The paper develops an empirical study gathered from a traditional shipbuilding industry, its suppliers, and customers. This study consists of three sections: the traditional shipbuilding industry, the suppliers, and the individual supplier scores. The internal and external performances in this study are measured using Supply Chain Operations Reference (SCOR) metrics. The SCOR model identifies five performance measurement attributes, including reliability, flexibility, responsiveness, cost and assets. Instead of using “responsiveness,” this study applies the schedule performance index, and supplements “cost” with the cost performance index in order to accurately reflect the traditional shipbuilding supply chains processes.

By analyzing SCOR metrics in the traditional shipbuilding industry, it has been found that the ideal shipbuilding supply chain metrics are order fulfillment, flexibility, asset turnover and total supply chain costs. The lowest performance metric value in the traditional shipbuilding industry is the cost of goods. Some improvements are proposed to lower the high cost of ship building. An integrated economic ordering system in collaboration with all the suppliers is one of the most effective ways to reduce the cost of the traditional shipbuilding supply chains. The implementation of SCOR metrics enables management to identify the critical issues to improve.

The study applies SCOR metrics to improve the traditional shipbuilding supply chains performance. The study is limited because the data collected are based on one shipbuilding industry only.

To the author's knowledge, this is the first empirical analysis on the implementation of SCOR metrics to the traditional shipbuilding industry. The analysis to improve the traditional shipbuilding supply chains performance can provide managerial insights to other industries.

The paper constructs an annual price series for English net agricultural output in the years 1209–1914 using 26 component series: wheat, barley, oats, rye, peas, beans, potatoes, hops, straw, mustard seed, saffron, hay, beef, mutton, pork, bacon, tallow, eggs, milk, cheese, butter, wool, firewood, timber, cider, and honey. I also construct sub-series for arable, pasture and wood products. The main innovation is in using a consistent method to form series from existing published sources. But fresh archival data is also incorporated. The implications of the movements of these series for agrarian history are explored.

This chapter presents mathematical model for geothermal energy allocation. The objective is to a find the minimal length of connections between sources and demand points. The problem is formulated as a transportation problem. The model presented in this case study finds optimal assignment of energy sources to urban areas, with full demand for energy satisfied in all districts using one type of energy.

Describes a selection of innovative products, exhibited at NEOCON 92 in Chicago. These include environmental control devices, office wireless communications, personal workplaces, adjustable‐height work‐surfaces, storage units and office furniture.

A recent television programme in ‘The World About Us’ series showed the various six‐legged or four‐footed sitting tenants and unwelcome visitors that find an old cottage a desirable residence at the various seasons of the year. Through the stages of its conversion and re‐occupation by people, some insects, fungi, rodents, mites and moulds disappeared, only to be replaced by other species more adapted to the new environment. ‘Vacant Possession’ is a relative term.