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The purpose of this paper is to communicate and share experiences with other dam designers, operators and maintenance officers arising from the rehabilitation of the Osborne Dam outlets, pursuant to informing future dam outlet designs and rehabilitation of similar dam outlets.

This paper documents and utilizes actual events that occurred before and during the rehabilitation of the outlets. Some solutions applied were unique, with resultant innovative engineering designs being decided on site. Realizing that a descriptive research format would best serve the sharing of experiences of the outlets’ rehabilitation, the case study approach was selected. Before commencement of the rehabilitation works, the different operational problems that had been identified, photographed and documented by the dam’s operating staff were verified by the dam owner’s engineers, technicians and consultants. Visual and photographic verification was done using divers for areas under water. Literature review was conducted so as to learn from solutions employed elsewhere. A physical model of the solution considered the best way to keep the intake tower dry was made and tested.

The outlets’ rehabilitation works, taking 12 months to complete at a total cost of US$5 million, involved installation of new service gates, replacement of the sleeve valves, refurbishment of the butterfly valves and provision of dewatering pumps.

This paper offers unique experiences and lessons for dam designers and other dam operation and maintenance officers while contributing to the body of knowledge of outlet works rehabilitation.

Multi-level intake structures are used to take the surface water of reservoirs. The changed boundary conditions will certainly make the water hammer phenomenon more complicated. This paper aims to find out the influence and law of the water hammer pressure after setting the stop log gates.

The authors use the computational fluid dynamics method with the adaptive grid technology to stimulate the water hammer phenomenon of the multi-level intake hydropower station. In the analysis, we set several different heights of stop log gates and two representative times in the starting up and shutdown processes to reflect the impact of multi-level intake structures.

The authors find that the setting of the stop log gates will reduce the pressure during the normal operation and will increase the period and amplitude of the water hammer wave, but will not necessarily increase the maximum water hammer pressure during the shutdown process. The relationship between the height of the stop log gates and the amplitude of the water hammer wave is affected by the shutdown time. After setting stop log gates, the depression depth and wave height of the water level in front of the dam increase when the load changes.

The authors study in this paper the water pressure of the multi-level intake hydropower station that has never been studied before and obtain some laws.

Peppy Barlow, herself a casualty of girls' education, returns to her home area to see what advances have been made in the past ten years.

The indexing of volumes made up of contributions by different authors raises questions which do not arise in indexing a treatise, a textbook, or a narrative by a single author. Such a book is a coherent whole. Its chapters, sections, and paragraphs are balanced so as to create in the reader's mind the pattern of knowledge or ideas and the distribution of emphasis the author intends. The language and style are uniform. The same special terms are used with the same meanings and implications throughout. All this makes it possible for the indexer to distinguish the wood from the trees and decide which kinds of trees call for more notice than others by scanning right through the book before he starts considering the details.

Legionnaires’ Disease is a comparatively new disease with the first cases identified in the United States of America in 1976, where a congress of Legionnaires met in a large hotel and subsequently a number fell ill and 29 died. Within the United Kingdom there has been a number of outbreaks (‘outbreak’ means identification of two or more people having the disease). Hospitals are no exception, being the source of eight outbreaks in the UK (between 1979 and 1984). People attending and visiting hospitals include those most vulnerable to the disease, the old and those suffering from chronic illnesses; thus any hospital‐associated outbreak is the subject of local and national concern. The Stafford outbreak in 1985 affected more people than in any previous hospital outbreak, causing the death of 22 patients. The scale and severity of the incident and its association with a new hospital was the subject of a public inquiry, the first to be held into an outbreak of Legionnaires' Disease in this country.

The purpose of this paper is to explore the location of fast-food outlets around secondary schools and the influence of fast-food availability on the food choices of school children in an inner-London borough.

A number of methods including: mapping of outlets relative to schools; sampling food; gathering data on secondary school food policies; observing food behaviour in fast food outlets and focus groups with young people. Findings were fed back to a committee consisting of representatives from nutrition, public health, planning services and local community groups.

There are concentrations of fast-food outlets near schools and students reported use of these, including “stories” of skipping lunch in order to save money and eat after school at these outlets. Food from fast-food outlets was high in fat, saturated fat and salt, but these are not the only source of high such foods, with many of the students reporting buying from shops near the school or on the way to or from school. At lunchtime food outlets were less likely to be used by school students in areas near schools that have a “closed gate” policy.

The “snapshot” nature of the research limited what can be said about the food behaviours of the children outside school hours.

The local policy context requires action to improve both the food offered in schools and the immediate environment around the school in order to tackle fast-food and other competitive foods on offer outside the school.

This is one of the first studies in the UK to systematically map fast food outlets around schools and explore what might be done. This research shows how it is possible to link the findings of local research and develop local responses from both public health and local authority planning perspectives. The research moves away from a mere documenting of problems to devising integrated public health solutions. The findings show how public health and planning services can work together to the mutual benefit of each other.

PM10 is one of the most dangerous air pollutants which is harmful to the ecological system and human health. Accurate forecasting of PM10 concentration makes it easier for the government to make efficient decisions and policies. However, the PM10 concentration, particularly, the emerging short-term concentration has high uncertainties as it is often impacted by many factors and also time varying. Above all, a new methodology which can overcome such difficulties is needed.

The grey system theory is used to build the short-term PM10 forecasting model. The Euler polynomial is used as a driving term of the proposed grey model, and then the convolutional solution is applied to make the new model computationally feasible. The grey wolf optimizer is used to select the optimal nonlinear parameters of the proposed model.

The introduction of the Euler polynomial makes the new model more flexible and more general as it can yield several other conventional grey models under certain conditions. The new model presents significantly higher performance, is more accurate and also more stable, than the six existing grey models in three real-world cases and the case of short-term PM10 forecasting in Tianjin China.

With high performance in the real-world case in Tianjin China, the proposed model appears to have high potential to accurately forecast the PM10 concentration in big cities of China. Therefore, it can be considered as a decision-making support tool in the near future.

This is the first work introducing the Euler polynomial to the grey system models, and a more general formulation of existing grey models is also obtained. The modelling pattern used in this paper can be used as an example for building other similar nonlinear grey models. The practical example of short-term PM10 forecasting in Tianjin China is also presented for the first time.

In order to optimize SCSWIRC, the simplification and further optimization method is proposed. SCSWIRC's optimization includes two levels. The first level refers to simplifying structural system from the perspective of components; the second level refers to optimizing components' sectional areas from the perspective of mechanics. The first level aims to remove redundant components, and the second level aims to reduce structural self-weight based on the first level. The purpose of the paper is to simplify SCSWIRC's structural system and optimize structural self-weight and reduce construction forming difficulty.

Grid-jumping layout and multi-objective optimization method is used to simplify and further optimize Spatial cable-truss structure without inner ring cables (SCSWIRC). Grid-jumping layout is used to simplify remove redundant components, and multi-objective optimization method is used to reduce structural self-weight. The detailed solving process is given based on grid-jumping layout and multi-objective optimization method.

Take SCSWIRC with a span of 100m as an example to verify the feasibility and correctness of the simplification and further optimization method. The optimization results show that 12 redundant components are removed and the self-weight reduces by 3.128t from original scheme to grid-jumping layout scheme 1. The self-weight reduces from 36.007t to 28.231t and feasible coefficient decreases from 1.0 to 0.627 from grid-jumping layout scheme 1 to multi-objective optimization scheme. The simplification and further optimization can not only remove the redundant components and simplify structural system to reduce construction forming difficulty, but also optimize structural self-weight under considering structural stiffness to reduce project costs.

The proposed method firstly simplifies SCSWIRC and then optimizes the simplified SCSWIRC, which can solve the optimization problem from the perspective of components and mechanics. Meanwhile, the optimal section solving method can be used to obtain circular steel tube size with the optimal stiffness of the same areas. The proposed method successfully solves the problem of construction forming and project cost, which promotes the application of SCSWIRC in practical engineering.

The paper aims to develop a particle matter (PM_2.5) prediction model for open-plan office space using a variety of data sources. Monitoring of PM_2.5 levels is not widely applied in indoor settings. Many reliable methods of monitoring PM_2.5 require either time-consuming or expensive equipment, thus making PM_2.5 monitoring impractical for many settings. The goal of this paper is to identify possible low-cost, low-effort data sources that building managers can use in combination with machine learning (ML) models to approximate the performance of much more costly monitoring devices.

This study identified a variety of data sources, including freely available, public data, data from low-cost sensors and data from expensive, high-quality sensors. This study examined a variety of neural network architectures, including traditional artificial neural networks, generalized recurrent neural networks and long short-term memory neural networks as candidates for the prediction model. The authors trained the selected predictive model using this data and identified data sources that can be cheaply combined to approximate more expensive data sources.

The paper identified combinations of free data sources such as building damper percentages and weather data and low-cost sensors such as Wi-Fi-based occupancy estimator or a Plantower PMS7003 sensor that perform nearly as well as predictions made based on nephelometer data.

This work demonstrates that by combining low-cost sensors and ML, indoor PM_2.5 monitoring can be performed at a drastically reduced cost with minimal error compared to more traditional approaches.

To furnish a control force an aerofoil is formed with a duct connecting an outlet opening at the surface with a forwardly‐directed intake opening at or in advance of the leading edge, so that air entering the intake due to motion of the aircraft issues from the outlet to produce the control force. Normally a pair of superposed ducts 21, 22 are provided as shown in FIG. 1, with inlets 23, 24 at the leading edge and outlets 25, 26 on the opposite surfaces of the aerofoil, pivotal closure members 27, 28 being provided for the inlets and slidable closure members 29, 30 for the outlets. When applied to wing tips for roll control purposes the outlets may be placed side‐by‐side, being of unequal area to compensate for their different distances from the longitudinal axis of the aircraft. FIG. 2 shows an arrangement for use with tail planes 3,90, the outlets 83, 84 communicating through ducts 81, 82 with an annular air inlet formed between a cowl 87 and the fuselage tail 88. Closure members 91 and 92, 93 fitted to the tail of the cowling 87 and the ducts 81, 82, respectively, are so arranged that in normal operation member 91 is in the open position and members 92, 93 in the closed position, this arrangement being reversed when control forces are required.