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The purpose of the paper is to present component matching and off-design calculations using generic components maps.

Multi objective hybrid optimization code is integrated with turbojet function code. Both codes are developed for the research study. Initially, methodology is applied on a numerical propulsion system simulation (NPSS) example engine cycle calculations. Effect of matching constants are shown. Later, component matching and application is done on JetCat engine. Calculations are compared with measured test data. And additional operating conditions are calculated using the matched component constants.

Obtained matching constants provided very good results with NPSS example and also JetCat test measurements. Optimization algorithm is practical for turbojet engine component matching and off-design calculations. Off-design matching provides information about the turbine and exhaust areas of an unknown turbine engine. Thus it is possible to perform off design calculations at various operating conditions. Finding detailed turbine maps is difficult than finding compressor maps. In that case characteristic turbine curve may be a good alternative.

Selected component maps and the target engine components should be similar characteristics. For a one/two stage turbine, characteristic curves can be applied. Validation should be extended on different type of compressor and turbines.

Operators and researchers usually need more information about the available turbojet engines for increasing the effective usage. Generally, manufacturers do not provide such detailed information to public. This study introduces an alternative methodology for engine modeling by using generic component maps and thus obtaining information for off-design calculations. User is flexible for selecting/scaling the compressor and turbine maps.

A hybrid optimization code is used as a new approach. It can be used with other engine functions; for instance functions corresponding to turboshaft or turbofan engines, by modifying the engine function. Number of input parameters and objective functions can be modified accordingly.

The architecture, engineering and construction industry faces several challenges when performing life-cycle cost calculations. On the basis of activity theory, this study aims at improving our understanding of the current cost calculation in design practices as an activity system with a number of built-in contradictions.

Drawing on one of the authors’ practical experience from a design office, the research design comprises a paradigmatic case study of a Danish architecture firm, in which data are gathered through documents, observations, interviews and physical artefacts. Moreover, this paper applies a literature review on barriers for adopting life-cycle costing.

The paper identifies a number of primary, secondary, tertiary and quaternary contradictions between practices of design, cost calculations and data management. Thus, hypotheses are formulated on how and to what extent these different contradictions shape cost calculations in design practices to obstruct or support the application of life cycle costing principles in design.

This study is part of an ongoing research project. Thus, additional analysis is required before the authors may conclude on final results.

This paper identifies a number of factors that obstruct or support the implementation of life cycle costing in current design practices.

This paper provides new insights into the various contradictions that shape data management in architectural offices as a prerequisite for improving life cycle design practices.

Introduces papers from this area of expertise from the ISEF 1999 Proceedings. States the goal herein is one of identifying devices or systems able to provide prescribed performance. Notes that 18 papers from the Symposium are grouped in the area of automated optimal design. Describes the main challenges that condition computational electromagnetism’s future development. Concludes by itemizing the range of applications from small activators to optimization of induction heating systems in this third chapter.

This paper aims to reliability analysis of axially loaded steel columns at elevated temperatures considering the probabilistic features of fire.

The response function used in the reliability analysis is based on the non-linear FEM calculations. The stochastic variability of temperature is integrated with the procedure similar to the parameters of loading and material properties. Direct Monte Carlo simulations (MCSs) are implemented for probabilistic analysis. Computational costs are reduced by polynomial approximation of the response function of the column.

A design method for practical applications in the common Eurocode format is proposed. The proposed method can be used to estimate the failure probability of a steel column in fire conditions. If standard reliability criteria are applied, the results of the steel column buckling capacity in the fire according to the proposed procedure deviate from the Eurocode results in certain parameter ranges.

The proposed method for design calculations makes use of the advantages of MCS results, while the need for the tedious amount of calculations for the end user are avoided as the predefined factors are implemented in the procedure of Eurocode format. The proposed method allows better differentiation of the fire probability in the capacity assessment compared to the existing design methods.

This study aims to a launchable design has been made to prevent wasted time in time-critical areas, and increase the efficiency of the unmanned aerial vehicle (UAV). In this way, a UAV can reach the mission height quickly.

A unique launchable UAV and launcher mechanism have been designed. The launchable UAV will be folded into the launcher mechanism and will automatically start flight after launch. The study includes mathematical calculations, 3D designs steps and produced UAV tests for the designed UAV. The launcher mechanism was designed in accordance with the tests for the UAV, and appropriate choices were made for the altitude and launch acceleration required by the UAV. According to the calculations, material selection and production were made.

In the tests, the climbing time was reduced by 1 s compared with the existing UAVs. With the launch, it enabled it to reach the altitude quickly and silently. In addition, because the launch energy was provided externally, it provided an advantage for the flight time.

A rotary-wing UAV with a launch mechanism and a fast launch was designed and prototyped. The maximum climb speed of the designed drone is 6.52 m/s. Frame arm length is 9.2 cm, propeller diameter is 15.24 cm and hover flight time is 7.2 m.

The UAV design can be launched. Design, calculation and experimental studies have been carried out for rapid take-off of the rotary wing UAV. The parts used in the UAV are originally produced. It is not a commercial product.

To provide input data to design and energy performance calculations of buildings and ventilation, heating, cooling and lighting systems.

European directive for energy performance of buildings was approved in the beginning of 2003. The transition period is 3‐6 years depending on the article. European Standardisation Organisation (CEN) has drafted several standards to help the member countries implementing the directive. One of these is the “Criteria for the indoor environment including thermal, indoor air quality (ventilation) light and noise.” The standard has been developed based on existing international standards and guidelines for the indoor environment taken into account the latest results from published research.

The standard specifies design values of indoor environment, values to be used in energy calculations, and methods how to verify the specified indoor environment in the buildings. The paper describes some of the principles used in standards, and gives examples presented in the standard. The standard covers all building types but the paper is focuses on the non‐residential buildings, numeric examples are given only for offices.

The draft standard is under international review process during writing this paper, and subject to changes. The standard give default criteria for the indoor environmental parameters, which can be used if no national requirements are available.

This paper describes the indoor environmental parameters, which are important for people's health, comfort and energy consumption of buildings. This will help users to select more uniform input data for energy calculations.

This method will become a new development trend in subgrade structure design for high speed railways.

This paper summarizes the structural types and design methods of subgrade bed for high speed railways in China, Japan, France, Germany, the United States and other countries based on the study and analysis of existing literature and combined with the research results and practices of high speed railway subgrade engineering at home and abroad.

It is found that in foreign countries, the layered reinforced structure is generally adopted for the subgrade bed of high speed railways, and the unified double-layer or multi-layer structure is adopted for the surface layer of subgrade bed, while the simple structure is adopted in China; in foreign countries, different inspection parameters are adopted to evaluate the compaction state of fillers according to their respective understanding and practice, while in China, compaction coefficient, subsoil coefficient and dynamic deformation modulus are adopted for such evaluation; in foreign countries, the subgrade top deformation control method, the subgrade bottom deformation control method, the subsurface fill strength control method are mainly adopted in subgrade bed structure design of high speed railways, while in China, dynamic deformation control of subgrade surface and dynamic strain control of subgrade bed bottom layer is adopted in the design. However, the cumulative deformation of subgrade caused by train cyclic vibration load is not considered in the existing design methods.

This paper introduces a new subgrade structure design method based on whole-process dynamics analysis that meets subgrade functional requirements and is established on the basis of the existing research at home and abroad on prediction methods for cumulative deformation of subgrade soil.

The purpose of this paper is to describe and categorize calculation methods for conducting a complete air conditioning study. More specifically, this paper is a general review of cooling loads calculation methods, psychrometric calculations for installing a central air conditioning unit, ways of fan coil units connection and air duct calculation methods.

This paper was based on two pillars: a dissertation for an industrial facility and technical information found after methodical research.

After a brief reference of the calculation methods and the air conditioning systems installed in this industrial facility, this paper concludes with the most appropriate calculation methods for this industrial facility.

This study describes some calculation methods. Thus, future research could be addressed toward the analysis of more methods.

This paper includes implications for choosing the most appropriate calculation method according to the air conditioning system installed.

The originality of this paper lies in the fact that, except for the theoretical part, there are some examples taken from a case study, thus it can be used as a future guide for selecting methods and systems of industrial air conditioning.

The purpose of this paper is to present a simple approach for calculation of the sensitivities in the free-form inverse design problems. The approach is based on the analogy with the similar tasks used in the signal-processing analysis. In the proposed case it is not required to solve an adjoint problem as in the most of the similar optimization tasks. The simulation engine used in the background is a Fast Boundary Element Method. The approach is validated on some known benchmark problems.

Inverse design is recognized nowadays as a crucial scientific grand challenge. Contrary to the conventional approach (“Given the structure, find the properties”) it purses a new paradigm (“Given the desired property, find the structure”). Inverse class of problems has a broad application area, from the material-, medical-, bio- to the engineering-class of problems. When dealing with the inverse design in free-form optimization of the engineering problems the typical approach is to calculate the adjoint problem. Calculation of the adjoint problem mostly requires the costly calculation of the gradients, which makes the whole optimization procedure rather expensive due to the high computational burden required for their solution.

In this paper it is proposed a novel Simple Sensitivity Approach to get in a fast way the response (sensitivity) function of the analyzed structure. The simulation engine used in the background is the Fast Boundary Element Method.

Novel approach for inverse design when performing the free-form optimization of engineering problems.

A combustor design is a particularly important and difficult task in the development of gas turbine engines. During studies for accurate and easy combustor design, reasonable design methodologies have been established and used in engine development. The purpose of this paper is to review the design methodology for combustor in development of advanced gas turbine engines. The advanced combustor development task can be successfully achieved in less time and at lower cost by adopting new and superior design methodologies.

The review considers the main technical problems (combustion, cooling, fuel injection and ignition technology) in the development of modern combustor design and deals with combustor design methods by dividing it into preliminary design, performance evaluation, optimization and experiment. The advanced combustion and cooling technologies mainly used in combustor design are mentioned in detail. In accordance with the modern combustor design method, the design mechanisms are considered and the methods used in every stage of the design are reviewed technically.

The improved performances and strict emission limits of gas turbine engines require the application of advanced technologies when designing combustors. The optimized design mechanism and reasonable performance evaluation methods are very important in reducing experiments and increasing the effectiveness of the design.

This paper provides a comprehensive review of the design methodology for the advanced gas turbine engine combustor.