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The purpose of this paper is to propose a combination bank-to-turn control mode with the single moving mass and reaction jet and design the roll control law for the long-range reentry maneuverable warhead.

Based on the dynamics model of this new control mode, the control model of roll channel is converted into a perturbed double-integrator system. The on-off optimal feedback control law is designed on the phase plane formed by Euler angle error and angular velocity error. To weaken the “on-off chattering” that is generated near the origin of the phase-plane and effectively reduce the jet fuel consumption for stability control, an on-off control outer ring and an inner ring are introduced into the phase plane.

This control mode can not only avoid the aerodynamic rudder ablation to improve the efficiency of attitude control, but also reduce the fuel consumption of jet control by using moving mass control. The simulation results indicate that the designed control law can meet the speediness and robustness requirements of the long-range maneuverable warhead controlled by the single moving mass and reaction jet. This measure can also eliminate the on-off chattering effectively.

The new control mode solves some engineering problems of long-range reentry maneuverable warhead controlled by only one actuator. The control mode has a promising prospect in engineering practice.

The paper provides a new control mode and a combination control strategy, and designs an effective control law.

THE Goodyear Antiskid System on the Hawk Aircraft provides indidividual brake control referred to as ‘On‐Off’ control as opposed to adaptive control. ‘On‐Off’ control removes all brake pressure when an incipient skid is detected and re‐applies pressure at a controlled rate to the pilot metered level when the skid condition has been corrected. This type of brake control is very cost effective and yet provides tyre protection, prevents loss of control due to locked wheels and with pilot participation, will provide safe stopping distances under the most severe runway conditions.

The purpose of this paper is to determine the optimal office lighting use with different types of lighting controls to achieve energy savings and provide visual comfort for individuals.

A case study and field measurements were carried out in 18 single-occupancy offices in Sweden where six different lighting controls were investigated. Occupancy and daylight hours were key issues for determining the lighting use. For each office, occupancy patterns, use of a ceiling luminaire, energy usage and perceptions of office lighting in the spring-summer and autumn-winter were established.

The use of luminaires varied among the occupants and could be habitual. Though the study yielded positive results concerning the potential for manual or daylight dimming with occupancy switch-off controls to increase optimal lighting use, combining dimming controls with manual on/off controls is rather effective if occupants generally sit in their offices most of the day.

Precise comparisons of the performances of the different controls were limited due to the offices’ different window orientations; thus, measurements in identical offices are desirable. The small sample size limited analyses of lighting use and the personal perceptions of lighting quality.

Apart from the contribution to simulation techniques, the findings imply that office lighting controls should be selected taking individuals’ behavioural patterns and perceived lighting quality into consideration.

This paper describes an approach to determine the use of lighting controls and provides a basis for establishing optimal lighting use for individuals with regard to occupancy and daylight availability.

This paper aims to study the minimizing of energy consumption in air cooled-heat exchanger through a convenient control system. Thus, the performance of a given air cooler has been considered in different weather conditions for both ideal and non ideal operations.

The minimum number of fans in service has been calculated and used for the study and assessment of a proper controlling system with the purpose of energy saving in air coolers. On-Off controlling has been compared to variable speed drivers controlling to determine a feasible method for the process control of this cooling equipment.

Economical parameters show that installing variable speed drivers could be rational, as the payback period, the net present values of investment and the internal rate of return are completely persuading. The internal rate of return (IRR) for installation of variable speed driver (VSD) controls is 69 per cent. According to the results, there is a possibility of 0.45 and 0.33 MWh energy consumption reduction for VSD control under ideal and non-ideal conditions and consequently reduces annually 318 and 237 ton equivalent CO₂.

Air cooled heat exchangers are used as one of the energy consumption equipment in most plants, but before the emergence of serious problems, not enough attention was given to their operation.

WHILST much is heard of the new era in air transportation heralded by the wide‐bodied or ‘Jumbo’ jets and the supersonic transport, a quit revolution istaking place in the provision of ground facilities, especially in the world of air traffic control.

THE Trident IE fuel system, designed to operate on cither kerosene or JP.4, has a straightforward layout with few controls. Five integral tanks (FIG. 1), comprising four in the wings and one in the centre section, give a total of 5,880 Imp. gall, of which 2,000 Imp. gall, are contained in the centre tank. (Total fuel capacity of the Trident 1C is 4,960 Imp. gall, with 1,160 Imp. gall, in the centre tank.) Each wing inner tank has slightly more than twice the capacity of the outer.

In the context of a developing country, Indian buildings need further research to channelize energy needs optimally to reduce energy wastage, thereby reducing carbon emissions. Also, reduction in smart devices’ costs with sequential advancements in Information and Communication Technology have resulted in an environment where model predictive control (MPC) strategies can be easily implemented. This study aims to propose certain preemptive measures to minimize the energy costs, while ensuring the thermal comfort for occupants, resulting in better greener solutions for building structures.

A simulation-based multi-input multi-output MPC strategy has been proposed. A dual objective function involving optimized energy consumption with acceptable thermal comfort has been achieved through simultaneous control of indoor temperature, humidity and illumination using various control variables. A regression-based lighting model and seasonal auto-regressive moving average with exogenous inputs (SARMAX) based temperature and humidity models have been chosen as predictor models along with four different control levels incorporated.

The mathematical approach in this study maintains an optimum tradeoff between energy cost savings and satisfactory occupants’ comfort levels. The proposed control mechanism establishes the relationships of output variables with respect to control and disturbance variables. The SARMAX and regression-based predictor models are found to be the best fit models in terms of accuracy, stability and superior performance. By adopting the proposed methodology, significant energy savings can be accomplished during certain hours of the day.

This study has been done on a specific corporate entity and future analysis can be done on other corporate or residential buildings and in other geographical settings within India. Inclusion of sensitivity analysis and non-linear predictor models is another area of future scope.

This study presents a dynamic MPC strategy, using five disturbance variables which further improves the overall performance and accuracy. In contrast to previous studies on MPC, SARMAX model has been used in this study, which is a novel contribution to the theoretical literature. Four levels of control zones: pre-cooling, strict, mild and loose zones have been used in the calculations to keep the Predictive Mean Vote index within acceptable threshold limits.

An intelligent building incorporates two key components: automated building control systems and information management control systems. Automated building control systems include energy management systems, automated security and fire systems, and network life‐support systems. Information management control systems include telecommunications, data networking, local area networks, and other short and long haul networks. When these systems are linked together with common wiring and central controls, the building becomes intelligent. The integration of these components in Infomart, a high‐tech facility located in Dallas, Texas, is described. The usage of these components by tenants, and their possible application to library buildings are discussed.

The purpose of this study was to examine lighting systems at 77 laboratories located within one building to save energy and associated costs.

Field measurements of illumination were conducted and compared to lighting standards and industry recommendations.

For energy and cost saving, de-lamping all four-lamp luminaires down to two-lamp luminaires and installing occupancy sensors in all laboratories were recommended.

The research team’s project working hours and study period were limited. This study begins to fill the gap in the literature regarding lighting field studies.

By carefully considering light level recommendations, industry standards and installation budgets, existing facilities can install appropriate retrofits to save energy and money without sacrificing illumination levels. Recommended retrofits are anticipated to significantly curtail annual federal energy consumption practices at the labs.

The retrofits recommended in this study will reduce US federal government’s energy-related expenditures and greenhouse gas emissions in support of the 2010 Presidential Mandate. The proposed occupancy sensors are anticipated to compensate for humans’ failure to manually control lighting.

This field study adds value by documenting cost-effective methods to measure, record and manage laboratory lighting, and it calls for the implementation of social, economic and ecological interventions. The recommended retrofits will reduce US federal government’s energy-related expenditures and greenhouse gas emissions in support of the 2010 Presidential Mandate.

This paper aims to show the current situation and additional requirements for the aircraft automation systems based on the lessons learned from the two 737 MAX crashes.

In this study, the Swiss cheese model was used to find the real root causes of the 737 MAX accidents. Then, the results have been compared with the actions taken by the manufacturers and authorities. Based on the comparison, the necessary improvements to prevent such accidents are defined. Regarding the faulty sensor that forms the accidents, a synthetic sensor was developed using an aerodynamic model.

It has been proven that the safety-critical automation systems should not be designed by relying on a single set of sensor data. Automation levels should be defined in a standard way. Depending on the defined automation level, the system must be designed as either fail-safe or fail-operational system. When designing backup systems, it should be decided by looking at not only whether it has power but also the accuracy of the incoming signals.

Aviation certification requirements related to automation systems need to be revised and improved. With this context, it was revealed that the certification processes for automation systems should be re-evaluated and updated by aviation authorities, especially Federal Aviation Administration and European Union Aviation Safety Agency.

Task sharing between automation system and pilot based on the classification of automation levels and determining certification requirements accordingly has been brought to the agenda. A synthetic Angle of Attack sensor was developed by using an aerodynamic model for fault detection and diagnosis.