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This paper provides a comprehensive check list of Nolinae species recorded in Hong Kong, China based on the collections of the second author, Dr. Roger Kendrick and the Natural History Museum, London. The checklist comprises 30 species. Two of them are new to science and described here as new species (Spininola kendricki sp. n., and Hampsonola ceciliae sp. n.). Misidentification of the female paratype of Spininola nepali László, Ronkay & Ronkay, 2014 is revealed and the true female of S. nepali is illustrated with its genitalia described here for the first time. The hitherto unknown female of S. armata László, Ronkay & Witt, 2010 is also illustrated here for the first time. All species recorded from Hong Kong are illustrated together with their genitalia on 54 colour and 46 black and white diagnostic figures.

Within the wind engineering community, a series of physical simulators of differing geometries have been used to investigate the flow-field of tornado-like vortices. This paper examines the influence that the geometry of a simulator can have on the generated flow field. Surface pressure and velocity data have been measured for two swirl ratios (S = 0.30 and S = 0.69) in two different simulators of different scale and varying geometry. The results of this research suggest that far from being a mature research field, there are still many unresolved questions that need to be addressed before data obtained from such simulators can be used with confidence in practice.

In recent years a number of Tornado Vortex Generators (TVGs) have been constructed and tested, with a view to providing facilities that can be used to determine wind loads on a variety of structures in tornado conditions. The scaling of TVGs has however proved to be contentious and different authors have taken different approaches. In this paper we address this issue and firstly present a formal dimensional analysis of the flow within full scale tornadoes and TGVs, which identifies a number of important dimensionless groups. We then consider a range of full-scale tornado data and, as far as possible, derive values of these dimensionless groups for each tornado. This analysis is then used to define the ranges of the dimensionless parameter for three tornado types (all of the two cell form) that can be used as simulation targets, rather unimaginatively naming them small, medium and large tornadoes. We then consider the performance of four medium to large TVGs in achieving these simulations. The analysis shows that the larger TVGs can achieve a range of geometrical similarities for the small and medium simulation targets, but none are able to achieve kinematic similarity, in that the ratio of circumferential to radial velocities are significantly lower than at full scale. Dynamic similarity (based on the Reynolds number) is of course not possible for physical models, but the analysis shows that in almost all cases the Reynolds number and model scales fall well below what would be considered acceptable in atmospheric boundary layer wind tunnels. We thus regretfully conclude that current TVGs are not wholly fit for purpose at the moment and are in need of significant modification if they are to be used to give reliable loading data. Alternatively it may be that the wind engineering community should consider different types of simulation to obtain the required information.

There has been much debate of late regarding the physical simulation of downbursts and, in particular, the need to construct large-scale, relatively expensive facilities in order to obtain wind loading data. For the first time, this paper illustrates that, through the use of partial turbulence simulations and quasi-steady analysis, it is possible to capture the both the loading due to the large-scale features present in downburst flows and the local peaks due to smaller scales of turbulence. These findings have considerable implications for future analysis of transient winds.

It is well known that tornadoes passing over fields can cause significant damage to crops, and tornado tracks of fallen, or lodged, crops can extend for many hundreds of metres. An examination of photographic evidence of such events suggests that, at least for low speed EF0/EF1 events, lodging occurs beneath tornadoes primarily due to a strong radial flow (rather than circumferential flow) at the canopy surface. In order to investigate this effect further, a simple model of a tornado has been developed which, whilst fully satisfying the three dimensional Euler equations, models a circumferential flow at the edge of the tornado boundary layer near the ground, which becomes a radial flow as the ground is approached. This model is then used in a generalised model of lodging to predict lodging track widths and crop fall directions. It is shown that, when expressed in a suitably normalised form, both lodging width and crop fall direction are functions of a normalised translational velocity and a normalised crop lodging velocity. The lodging patterns are of two forms - a forward convergence (FC) where the cropfall converges on the tornado track in a forward direction, and a backward convergence (BC) where the convergence is in the opposite direction to tornado translations. Regions of FC and BC in the normalised parameter plane are calculated. These patterns are very similar to those observed in the field, which gives some confidence in the nature of the model. The model is then used to investigate the sensitivity of lodging width to crop and tornado parameters, and also to carry out a risk analysis to determine the probability distributions of lodging width for specified distributions of crop and tornado parameters.

This paper examines the impact that climate change may have on the lodging of oats in the Republic of Ireland and the UK. Through the consideration of a novel lodging model representing the motion of an oat plant due to the interaction of wind and rain and integrating future predictions of wind and rainfall due to climate change, appropriate conclusions have been made. In order to provide meteorological data for the lodging model, wind and rainfall inputs are analysed using 30 years’ time series corresponding to peak lodging months (June and July) from 38 meteorological stations in the United Kingdom and the Irish Republic, which enables the relevant probability density functions (PDFs) to be established. Moreover, climate data for the next six decades in the British Isles produced by UK climate change projections (UKCP18) are analysed, and future wind and rainfall PDFs are obtained. It is observed that the predicted changes likely to occur during the key growing period (June to July) in the next 30 years are in keeping with variations, which can occur due to different husbandry treatments/plant varieties. In addition, the utility of a double exponential function for representing the rainfall probability has been observed with appropriate values for the constants given.

BACKGROUND: Carcinoma of unknown primary represents a therapeutic challenge in oncological practice. Evidence lacks to support particular chemotherapy selection and empirical therapies are commonly extrapolated from data on patients where primary tumor site is known. Gemcitabine, Oxaliplatin, Leucovorin and 5-Fluorouracil was previously developed to treat pancreatic cancer. These agents have also demonstrated activities in other gastrointestinal malignancies. Considering promising anti-tumor effects of GOLF, we performed a retrospective study to investigate anti-tumor activity and safety of a simplified Gemcitabine, Oxaliplatin, Leucovorin and 5-Fluorouracil in patients with Carcinoma of unknown primary in whom immunohistostaining was suggestive of either upper gastrointestinal cancers or pancreatobiliary cancers. METHODS: This retrospective study included 18 patients recorded to have a diagnosis of Carcinoma of unknown primary between Aug 2010-Dec 2015, who received biweekly G 1000 mg/m(2), O 85 mg/m(2), L 200 mg/m(2) and F 2400 mg/m(2) over 46-h on day 1 with pegfilgrastim on day 3 every 14 days. IHC staining pattern favored upper GI origin, including stomach, bile duct or pancreas. Tumor assessments were repeated every 8 weeks. RESULTS: Median age was 67 years (range: 46–76), with ECOG PS

This paper presents a novel conceptual design framework which takes into account the direct wind loads and pressure loads acting on a structure due to the passing of a tornado. Furthermore, for the first time, the potential damage due to debris impact has been incorporated enabling a holistic assessment of structural loading to be considered. The model is built on a recently developed wind and pressure field model that captures the main features of tornadoes, which is used to generate a large number of tornado wind and pressure field realisations from which values of particular load effects can be determined. A cumulative distribution function of load effect is thus derived, which can be combined with tornado climatology probabilities to determine load effects at a particular risk level. This use of this framework is illustrated through two examples – the direct wind and pressure loads on a low-rise portal frame structure, and the debris loads on a medium rise rectangular structure.

Given the difficulties associated with undertaking full-scale measurements in tornadoes, recourse is often made to models. In this field, analytical models have, perhaps surprisingly, stood the test of time, with the Rankine, Burgers-Rott and Sullivan models frequently invoked to model the flow field of a tornado. These mathematical models are by their very nature, a simplification of what is a highly complex phenomenon. However, in many cases they have been represented as the ‘truth’ without the fundamental assumptions governing the model being either explored in detail or even acknowledged. This paper attempts to rectify this by giving detailed information about assumptions and limitations of each vortex model and critically assesses the ability (or otherwise) of the Rankine, Burgers-Rott, Sullivan, and the recently published Baker vortex model to simulate tornado-like flow. Comparisons are made to the flow field of a physically simulated tornado, which by its very nature is also a model, but arguably more realistic. It was found that the vortex models are able to represent certain flow patterns at certain heights but fail, due to their simplifications, in replicating the entire three-dimensional flow structure obtained experimentally.

This paper describes the derivation of a simple yet realistic engineering model of tornado wind and pressure fields. This novel model is shown to be capable of providing a method for predicting wind speed and pressure time histories and debris impact energies that can ultimately be used in the development of a rational risk-based design methodology for tornado wind loads on buildings. A stationary one-cell tornado vortex is first considered, and the circumferential and vertical velocities and pressure profiles derived from a simple assumption for radial velocity (that is bounded in the radial and vertical directions) and the use of the Euler equations. The generalisation of this model to a two-cell tornado form is then set out. This model is then used to investigate the trajectories of wind borne debris in tornado wind fields, and for the first time, this analysis reveals the important dimensionless parameters of the problem and the parameter boundary between falling and flying debris. An asymptotic long time solution for debris paths is also derived.

Verified static and dynamic models of an operational works were used alongside Monte-Carlo conditions and non-dominated sorting genetic algorithm II (NGSAII) to optimise operational regimes. Static models were found to be more suitable for whole water treatment works optimisation modelling and offered the additional advantage of reduced computational burden. Static models were shown to predict solutions of comparable cost when applied to optimisation problems while being faster to simulate than dynamic models.

Flumes with either width contractions or raised beds to force modular flow conditions (i.e. a transition from sub- to super-critical flow) are a widely used instrument for the measurement of flow rate. The conservation of mass, written as the continuity equation, and the conservation of energy are combined with the existence of a critical depth point to derive a theoretical equation for the discharge as a function of the upstream water depth. This derivation requires a number of assumptions regarding the flow both upstream and in the throat of the contraction. The international standard covering the use of such flumes, ISO4359, places restrictions on the upstream position at which the water depth should be measured, which this work shows to be unnecessary, at least for the small (100 mm throat width) flumes examined. The assumption that critical depth occurs at the end of the flume throat is also shown to be incorrect, but has negligible effect on discharge calculation using the ISO4359 method.

This paper describes how wind engineering, geospatial science and crop agronomy disciplines can be combined to provide a decision support system for farmers to manage lodging risk, using the Crop Failure Assessment due to Lodging Losses (CROPFALL) framework. CROPFALL calculates lodging risk using information about topography, land cover, soil type and meteorological data, combined with a mechanistic model of lodging, and crop parameters. The risk of lodging is calculated at regional, farm, field and sub-field scales. The impact of crop management changes on lodging risk is simulated, demonstrating that modest crop management changes can achieve large reductions in lodging risk.

This chapter considers the effects of high winds on train operation. The various issues that arise from trains in high crosswinds are first outlined and a generic methodology is proposed for the consideration of these issues. Firstly, methods are outlined for determining the aerodynamic force and moment coefficients through the use of full-scale testing, physical model testing and CFD calculations. It is clear that the nature of the crosswind flow around trains at full scale is very complex, and model scale measurements and CFD calculations only provide a limited representation of the full-scale situation. Nonetheless, the force and moment coefficients from such tests are adequate for the overall calculation methodology. Such measurements have been made for a wide variety of trains in many different situations. These are tabulated in Appendix 2 , and this chapter provides a simple method of parameterising the results. A range of methods for simulating the natural wind are then critically presented, and the manner in which these simulations are combined with the force and moment coefficients and models of the vehicle dynamic system are set out to calculate the characteristic wind curve, which is used for train authorisation purposes. A simple methodology for calculating such curves is then described. Methods are then outlined for the calculation of the probability of a wind-induced accident occurring along an entire route. Finally, methods of reducing this accident risk, both through physical interventions and operational strategies, are discussed.

This chapter, building on the description of tunnel pressures and flows in Chapter 6 , discusses a range of practical issues associated with aerodynamic effects in railway tunnels. Firstly, pressure transients in tunnels are considered, and the range of methods used for calculating pressure transients in tunnels is set out, together with their input requirements. Aural pressure comfort is then considered, and the pressure transient limits specified by standards are described, together with an overview of the experiments from which these standards were derived. A probability-based approach to assessing aural comfort is also provided. Methods of reducing these pressure transients are then presented – through modification of tunnel geometry and train operating conditions, through the provision of airshafts or through the sealing of trains. Secondly, the emission of micropressure waves from tunnels is considered. Methods to reduce the inlet pressure gradients (and thus to reduce the magnitudes of these waves) are described – tunnel entrance hoods, elongated train noses, provision of cross shafts and the use of both passive and active aerodynamic damping devices. Finally, the chapter describes a range of other tunnel aerodynamic issues – train drag in tunnels, structural loading in tunnels and on trains and the very specific problems associated with long tunnels.

This chapter considers the aerodynamic behaviour of pantographs and overhead line systems. After an introduction to the geometry of such systems, the mechanical and aerodynamic forces on the overhead wire are set out. The static and dynamic displacement of the wire due to wind effects is described. Wire instabilities caused by galloping are then discussed at length and the circumstances under which these instabilities might occur are derived. The different types of pantograph are then discussed and the types of mechanical and aerodynamic forces experienced by pantographs are outlined. Full-scale measurements, wind tunnel measurements and CFD calculations of pantograph aerodynamic characteristics are considered. The important issue of pantograph aerodynamic optimisation is then discussed at length for both lift forces and drag forces. Finally, methods are described for analysing the dewirement problem and for predicting the risk of such incidents.

This chapter sets out some basic fluid mechanics concepts that are required in the study of train aerodynamics and that will be referred to later in this book. Dimensionless analysis and dimensionless variables are described, and this is followed by a discussion of two different frames of reference – the ground and train frames. Qualitative descriptions are then given of the principles of conservation of mass, momentum and energy, and of the concepts of free flows, boundary layers, turbulence, separated flows and wakes. This leads into a more quantitative discussion of the equations of motion in a variety of different forms, which will all be referred to later in this book. This section attempts to show the interrelated nature of many of the practical problems in train aerodynamics that might otherwise appear quite diverse. The nature of flow turbulence is then discussed in more detail, and this is followed by a description of the natural wind close to the ground, including wind speed probabilities, wind speed and turbulence profiles and turbulence spectra.

This chapter gives an introduction to the flow around trains in the open air and provides the basic description of the flow field on which the discussion of the applications in Part 2 is based. The discussion is built on the results of full-scale experiments, for a wide range of different train types, with data from model-scale experiments and computational fluid dynamics being used where no full-scale data are available. Firstly, the flow around trains on level ground is discussed, and the five basic flow regions are introduced – the nose region, the boundary layer region, the near wake region, the far wake region and the underbody flow region. Each of these regions is then analysed in turn, and data for typical pressure and velocity fields are presented. Information is presented on nose peak-to-peak pressure coefficients: train side, roof and underbody boundary layer parameters and roof and underbody skin friction for different train types. The unsteady vortex flow in the near wake region of high-speed trains is discussed in qualitative terms. The discussion then moves on to consider the flow around trains on level ground in crosswinds, considering both low and high wind speed conditions. The complexity and transient nature of these flow fields is emphasised. Finally, the flow around trains in a range of different environments is presented, and the effects of ballast platform height, embankments, viaducts and different station environments are discussed.

This chapter describes the nature of the flow in railway tunnels and forms the basis for the consideration of a number of practical issues in tunnel aerodynamics in Chapter 12 . The nature of the pressure transients caused by trains passing through tunnels is discussed in detail, and in particular the large changes in pressure as the train enters the tunnel are described. The concept of wave diagrams is presented, and the way it can be used to describe wave interactions is illustrated. The various factors that are associated with tunnel pressure changes are set out and discussed. In addition to the pressure changes, velocity changes in tunnels as trains pass through are also presented. The effects of airshafts on both tunnel pressures and velocities are then considered. Finally, the issue of micropressure waves (or sonic booms) from the exits of tunnels is discussed – both in terms of their generation through the steepening of entry pressure transients and their radiation outside the tunnel.

This chapter considers the aerodynamic loads caused by passing trains on trackside structure, people and other trains. These loads are of two forms – pressure loads and slipstream loads. Pressure loads are considered first and then the ways of quantifying the peak-to-peak pressure transients are described. The use of full-scale measurements, physical model measurements and CFD calculations to calculate these transients are then described, and the role of simple analytical methods are discussed. A range of correlations of pressure load data from standards is then presented, primarily concerned with loads on vertical structures next to the track and horizontal surfaces above the track. Pressure loads in station environments and on passing trains are also considered. The ways in which these pressure loads can be used to calculate structural loading are then described, ranging from simple static methods through to fully dynamic methods. With regard to slipstream loads, full-scale measurements require the measurement of slipstream gust speeds from a large number of train passes and the formation of an ensemble of gust speeds. Both physical model tests and CFD have some limitations in providing similar data. A collation of gust velocities for a wide range of train types is presented. The application of these gust speeds to loading of people and objects is then considered. A number of different approaches can be used and an overall framework that shows the interaction between these approaches is set out and described.

Modern software development tools typically provide a syntax highlighting feature to enhance the readability of source code. Syntax highlighting means that different kinds of terms in the text of source code are rendered in visually distinct ways. A syntax theme is a collection of definitions that determine the look of a workspace. Editors and IDEs often let the user customize the syntax theme to their preference and can also provide services for users to share themes within the community. This paper presents a data mining study of a large collection of publicly available syntax themes (approximately 330) associated with a popular open-source text editor. For each theme we collected certain metadata as well as a cascading stylesheet definition. The metadata includes information such as the title of theme, a plain text description, and specific programming languages supported by the theme. For each syntax theme, a preprocessor script creates a feature vector that aggregates data from the theme definition and metadata. Themes are analyzed with both RGB and HSV color models. Analysis shows a variety of significant correlations in the dataset as well general patterns of syntax theme usage. We also discuss how our dataset bears on previously established models of code comprehension.

Lodging is a major constraint to increasing the global productivity of maize (Zea Maize L.). The objectives of this paper are to: i) describe a model for stem and root lodging in maize, ii) calibrate the anchorage strength component of the model, iii) evaluate the model's applicability by assessing its capacity to explain effects of crop husbandry on lodging risk and iv) investigate the potential to further develop the lodging model to predict lodging risk at an early enough growth stage for tactical agronomic action to minimise lodging risk. The study involved a multidisciplinary collaboration between crop scientists, wind engineers and geospatial scientists in the UK and China. Three field experiments with plant population density and nitrogen (N) fertiliser rate treatments were conducted in the UK and China to develop and test the lodging model. Plant characteristics associated with lodging were measured in the experiments after flowering. An existing model of cereal anchorage strength that uses the spread of the root plate as its primary input was demonstrated to be applicable for maize and calibrated for this crop species. The lodging model's predictions of the effects of plant population and N fertiliser on lodging risk were consistent with published observations. The lodging model calculated that increasing the plant population significantly reduced the anchorage and stem failure wind speeds in all experiments, thus increasing the risk of lodging. This effect was primarily due to increased plant population reducing the spread of the root plate and the stem strength. Changes in N fertiliser had a smaller effect on the lodging associated plant characters. A sensitivity analysis showed that stem failure wind speed was influenced most by variation in stem strength and root failure wind speed was influenced most by variation in the spread of the root plate. This study has shown that the leaf area index measured at leaf 4, 6 or 8 stages is a good indicator of a crop's future risk of lodging, which demonstrates the potential to develop the model into a practical tool for predicting lodging risk in time for tactical agronomic decisions to be made during the crop's growing period. © 2020 Elsevier B.V.

This paper examines compact debris flight in tornado-like flow fields. The research focuses on physically simulating a specific tornado-like vortex and on investigating windborne debris flight with and without a low-rise building model. The low-rise building model, 1/8th scale with regard to the vortex core radius, was used to initiate the flight of Styrofoam spheres from its top. Debris motion was recorded using three high-speed cameras and data reduction was performed on open-source OpenPTV software. Flow field characterisation showed that including a building model does not considerably affect the averaged flow field but only the local instantaneous flow field. Debris flight analysis shows that the mean flight distance is not affected by the building model, but a change in the initial direction occurs. Comparison between local wind flow field and initial debris velocities shows good agreement, and therefore the variability in initial directions of the debris flight can be attributed to a wind-driven process. To compare with experimental data, experimental data were incorporated into debris flight equations to compute debris motion. Debris trajectories computed from experimental data show strong visual similarities with experimental trajectories and debris flight analysis presents good agreement with experimental data.

This paper presents the numerical study on the flight behaviour of spherical compact debris in a tornado-like wind field. The tornado-like vortex corresponding to a swirl ratio of 0.7 was generated using Large-eddy Simulation and the trajectories of 2250 individual debris particles placed in the flow were computed using Lagrangian-particle tracking. The debris corresponded to five groups (A, B1, B2, B3 and C) based on the value of the Tachikawa number (K) which ranged between 0.6 and 2.5. An analysis of the simulated flow field revealed that the tornado-like vortex consisted of two main features - a core at the centre with low velocity ( ∼ 0.25 m/s) which was surrounded by thick vortex wall composed of high velocity magnitudes ( ∼ 9.4 m/s). Updraft flows were observed around the core of the vortex and as a result, debris positioned around the core radius region were found to be 24% more likely to become wind-borne than debris positioned at the vortex wall region. Three groups of debris (B1, B2 and B3) with varying mass and density were studied for the aerodynamic similarity by retaining the fixed value of K = 1.2; all three debris groups exhibited the propensity to travel with similar flight characteristics. An analysis of the data pertaining to the fight behaviour of the three debris group (A, B1 and C) with varying K revealed that the low mass debris group A (K = 2.5) had the highest propensity to become wind-borne and was more likely to travel for the longest time with considerable variability observed in individual debris trajectories. However, somewhat counterintuitively, the high mass debris group C (K = 0.6) were found to have the furthest impact range despite their short flight duration; this was due the high mass debris being ejected out of the vortex with greater inertia, while debris with a lower mass had a tendency to be trapped in the flow that circulates around the vortex core.

The relative accuracy of static and dynamic water treatment works (WTWs) models was examined. Case study data from an operational works were used to calibrate and verify these models. It was found that dynamic clarification, filtration and disinfection models were more accurate than static models at predicting the final water quality of an operational site but that the root mean square errors of the models were within 5% of each other for key performance criteria. A range of abstraction rates at which the WTWs was predicted to operate adequately were identified using both types of models for varying raw water qualities. Static clarification, filtration and disinfection models were identified as being more suitable for whole works optimisation than dynamic models based on their relative accuracy, simplicity and computational demands.

For the first time, this research enables a systematic parametric analysis of oat lodging to be undertaken. A generalised lodging model combining agronomy, biology and wind engineering has been used. Standard husbandry treatments have been deployed in order to ensure that the oat plants are grown in realistic conditions and to ensure that the results are widely applicable. It is shown that the drag area, which increases through the growing season as the oats become entangled, is the plant trait which influences both stem and root lodging the most. In addition (and consistent with other plants) stem yield stress and the number of stems per plant for stem lodging and the diameter of the root structure in the case of root lodging, are found to play an important role. It is also shown that there is a linear relationship between failure anchorage moment and the cube of the root diameter in oats. Moreover, monitoring the lodging in crops which were grown under different husbandry treatments revealed using a resistant variety coupled with low Nitrogen rates and low seed rates, whilst also applying a Plant Growth Regulator (PGR) can increase the resistance of oat against lodging.