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The rapid expansion of oil palm (OP) has led to its emergence as a commodity of strategic global importance. Palm oil is used extensively in food and as a precursor for biodiesel. The oil generates export earnings and bolsters the economy of many countries, particularly Indonesia and Malaysia. However, oil palms are prone to basal stem rot (BSR) caused by Ganoderma boninense which is the most threatening disease of OP. The current control measures for BSR management including cultural practices, mechanical and chemical treatment have not proved satisfactory. Alternative control measures to overcome the G. boninense problem are focused on the use of biological control agents and many potential bioagents were identified with little proven practical application. Planting OP varieties resistant to G. boninense could provide the ideal long-term solution to basal stem rot. The total resistance of palms to G. boninense has not yet been reported, few examples of partial resistances have been observed. Importantly, basidiospores are now recognized as the method by which the disease is spread, and control methods require to be revaluated because of this phenomenon. Many methods developed to prevent the spread of the disease effectively are only tested at nursery levels and are only reported in the national journal inhibiting the development of useful techniques globally. The initial procedures employed by the fungus to infect the OP require consideration in terms of the physiology of the growth of the fungus and its possible control. This review assesses critically the progress that has been made in BSR development and management in OP., The authors thank the Ministry of Higher Education (MOHE) Malaysia for providing financial support under the project Fundamental Research Grant Scheme (FRGS/1/2019/STG05/UPM02/22) and University Putra Malaysia. We are also thankful to Dr Yuvarani Naidu from Malaysian Palm Oil Board for providing images of Basal Stem Rot disease symptoms from her personal collection. Professor Paterson is grateful for his second IOI Professorial Chair 2018/19., info:eu-repo/semantics/publishedVersion

The electrical resistance, and in particular, the electrical contact resistance (ECR), plays a critical role in the electrical and thermal behaviors of substation connectors. Despite its impact, there are very few research works analyzing the temperature dependence of the ECR and its terms, the constriction and film resistances. It is very important to understand the contribution of the ECR to the total resistance, and its dependence on temperature. This work studies these dependences in detail by analyzing two types of connectors, i.e., connectors intended to join tubular bus bars, and connectors for stranded conductors. Due to the specific features of bus bars and stranded conductors, the ECR of both conductors has a different impact on the total resistance. The experimental approach presented in this work can be applied to better understand the role of the contact resistance, allowing the design of improved and more reliable substation connectors and similar devices. This work was supported in part by the Ministerio de Ciencia e Innovación de España, under grant number RTC-2017-6297-3 and by the Generalitat de Catalunya under grant number 2017 SGR 967.

[EN] This study focuses on container vessel fuel consumption considering the wind conditions along the ship path in the liner route. Simple analytical and semi-empirical formulas are provided to estimate the total resistance force and the bunker consumption rate of fully loaded containerships between 5000 and 15000 TEU considering the effect of wind and the corresponding waves on the Beaufort scale. The bunker consumption rate is proportional to the total resistance force, so bad weather significantly increases fuel consumption. Examples of wind hindcasts and added resistance increases for the Atlantic Ocean, the Mediterranean Sea, and the Indian Ocean are provided for a better "a priori" estimation of the bunker consumption for a containership in a given route and time of the year, This work was supported by the Ministerio de Economia y Competitividad, Spain, and Fondo Europeo de Desarrollo Regional FEDER, EU [grant RTI2018-101073-B-I00].

The mean velocity of a river is set by the balance between gravitational driving force, which depends on depth and slope, and friction due to grain roughness and form drag. This chapter explains classic and recent resistance equations, discusses how their parameters relate to measurable channel properties and are used in numerical models, and outlines some more physically based approaches. Analysis of a large and diverse data set shows that Manning's n is seldom invariant with discharge, Strickler's equation for n usually underestimates total resistance, and most equations are least reliable for shallow flows.

Besides cake filtration and expression, cake formation, growth, and/or consolidation are also present in several other solid/fluid separation operations. The present chapter is devoted to the analyses and discussions of such problems. As an example, for gas emission control, fabric filtration is often applied. In fabric filtration, particle-laden gas is passed through filter bags such that filter cakes are formed outside bag surfaces. Because of the large quantities of gases to be treated and to insure bags' repetitive use, filter bags require periodic cleaning. A study of fabric filtration therefore must be based on the principles of cake filtration and that of filter cleaning. Another example would be cross-flow membrane filtration that is an application of the so-called membrane technology, which has become popular and important in recent years. Cross-flow filtration is commonly divided into two categories: (1) microfiltration for removing particles of size ranging from 10 −1 to 10 2 μm and (2) ultrafiltration for particles (or macromoleculars) with size up to 100 nm. Separation is achieved by the sieving effect and the membrane used functions as a sieve. The rejected (or removed) particles form cakes on the upstream side of the membrane. Unlike regular cake filtration discussed before in cross-flow filtration, the feed flow and the filtrate flow are not in the same direction. While the consequence of the cake formation is the same as that of regular cake filtration, namely, an increase of the total resistance to filtrate flow, the manner and the extent of cake formation in cross-flow filtration is quite different from the discussions given previously. This difference represents the main issues to be discussed in this chapter.

Publisher Summary This chapter provides guidelines for constructing a suitable and safe earth ground. An adequate earth ground system is extremely important to both user safety and correct operation of a control system. An earth ground, in parallel with the equipment ground system, safely conducts stray or induced electrical currents to earth. For digital switching circuits, several control system industry sources recommend a ground system that has a resistance of one ohm or less between the control system ground and true earth with a maximum resistance of three ohms. The control system ground must be at least as good as a ground associated with any other system. If a ground used with a radio communication system has a one-ohm resistance to true earth, the control system ground must have a one-ohm or less resistance to true earth. The electrical resistance of an earth ground system must be tested to ensure that the ground meets the requirements for control systems. The total resistance of the ground system is comprised of the resistance of the metal used in the plant earth ground grid, the resistance of ground cable connection to the grid, the resistance of the contact between the grid and earth, and the resistance of the earth itself.

This chapter is designed to discuss the various aspects related to ship resistance. The resistance of ships can be predicted by several methods. One method that has stood the test of time is by William Froude in 1870. He used planks and ship models to identify and demonstrate ship resistance. Nowadays ship models may be made in wood, paraffin wax or polyurethane foam. Ship models today range from being 3 to 10 m in length. Resistance can be divided into four groups: frictional resistance, wave-making resistance, eddy-making resistance, resistance due to wind and appendages. This chapter discusses the relationship between Froude speed-length law and Froude Number. Wind and appendage allowances very much depend upon the intended route for the new vessel. It is usual practice for Naval Architects to add 10-30% onto the total resistance obtained for calm water conditions. The higher percentages appertain for vessels operating on the more heavy weather routes.

Publisher Summary This chapter presents new empirical methods for prediction of ship resistance and wetted surface area of ships based on analysis of database of tests performed in the towing tank of MARINTEK. Artificial neural networks method is applied for analysis of the database. The methods are verified using several towing test results available. These methods show generally reliable simulation of residual resistance and wetted surface area of the ships. The method presented is a novel procedure for prediction of total resistance. A reliable prediction method is presented for the first time for prediction of total resistance of offshore vessels. To keep the method easy-to-use, the number of input parameters is limited. This has the consequence of ignoring design details like bulbous bow and appendages. These details may result up to 10% difference in the total resistance. Adding more input parameters will increase the accuracy for special cases; however, without access to sufficient additional exemplars, this may reduce generalization of the method.

Publisher Summary This chapter summarizes the results of a research program on high speed trimarans, jointly performed at Genoa, Naples, and Trieste Universities. Two geosim models of a trimaran hull equivalent to high speed vessels operating in the bay of Naples were built. Resistance tests were carried out to assess the best trim and configuration regarding the hydrodynamic resistance. Resistance and wave pattern tests were carried out separately on the main hull, on the outrigger, and on the trimaran. Due to very slender hulls the wave resistance of the considered trimaran is a low percentage of the total resistance and the wave interference phenomenon is generally beneficial to the trimaran. Preliminary seakeeping tests in regular waves show very significant differences of heave and pitch motions of the trimaran with respect to those of its main hull. The reported data seem to indicate a significant beneficial effect of the outriggers on the seakeeping performances.

This paper discusses how a systematic investigation of the resistance and roughness of two state-of-the-art alternatives to TBT-SPC was undertaken. The roughness and drag characteristics of two antifouling paint systems are investigated: a state-of-the-art (Tributyl) tin-free Self-Polishing Co-Polymer (SPC) and a non-toxic Foul Release system. Towing tank experiments have confirmed that the total resistance of 6.3-m plate coated wit the Foul Release coating system was on average 1.4% lower than when it was coated with both a stylus instrument and an optical measurement system. Correlation with the measured drag has shown that the roughness of the Foul Release cannot be characterized by a height parameter. The texture of the Foul Release surface is significantly different from SPC systems as is evident from parameters such as the average absolute slope Sa and the correlation length of the roughness profile. Roughness and drag seem to correlate well when the parameter is used to characterize the roughness.

Publisher Summary This chapter focuses on various aspects and concepts related to furnace aerodynamics. Gas flow in furnaces is turbulent but this turbulent flow may be steady or eddying. The force driving gases through a furnace system is the algebraic sum of—(1) the initial pressure; (2) the net pressures because of the various buoyancy effects where changes in level occur and including that in the final chimney, if any; (3) the pressures developed by any fans or injectors; and (4) the pressure losses because of frictional resistance to flow. The resistance of all several features in a system can be added together to obtain its total resistance to gas flow. An important aspect of furnace design is that heat should be developed at a required rate. Furnaces may operate under pressure or under draught. The aim should be that, either way, the pressure difference from atmospheric is as small as possible to minimize either drawing in cold air or escape of flame and gas through doors and brickwork.

This chapter discusses the resistors in series and parallel. When resistors are connected to each other end-to-end in such a way that they carry the same current, they are said to be connected in series. When resistors are connected to each other such that the same voltage is across each of them, they are said to be in parallel. The chapter also discusses mixed series and parallel circuits. It also presents the application of Kirchhoff's first law and explains how the total resistance of the three resistors of 3, 2, and 6 ohms can be found from the gradient of the graph.