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This paper aims to address the issue of designing aerodynamically robust empennage. Aircraft design optimization often narrowed to analysis of cruise conditions does not take into account other flight phases (manoeuvres). These, especially in unmanned air vehicle sector, can be significant part of the whole flight. Empennage is a part of the aircraft, with crucial function for manoeuvres. It is important to consider robustness for highest performance.

Methodology for robust wing design is presented. Surrogate modelling using kriging is used to reduce the optimization cost for high-fidelity aerodynamic calculations. Analysis of varying flight conditions, angle of attack, is made to assess robustness of design for particular mission. Two cases are compared: global optimization of 11 parameters and optimization divided into two consecutive sub-optimizations.

Surrogate modelling proves its usefulness for cutting computational time. Optimum design found by splitting problem into sub-optimizations finds better design at lower computational cost.

It is demonstrated, how surrogate modelling can be used for analysis of robustness, and why it is important to consider it. Intuitive split of wing design into airfoil and planform sub-optimizations brings promising savings in the optimization cost.

Methodology presented in this paper can be used in various optimization problems, especially those involving expensive computations and requiring top quality design.

Environmental scanning is that part of the strategic planning process which monitors emerging changes and issues and determines their likely impact on business decisions. While sophisticated scanning systems are not yet widely used in the banking industry, much has been learned about such systems in other industries. The paper illustrates how that knowledge might be applied to banks, S&Ls, and MBHCs, which are facing increasing levels of environmental change.

This issue of Retail Insights focuses on the subject of branding. There are a number of retail reports that offer valuable insights into current trends in branding. Professor Leslie de Chernatony analyses UK consumers’ attitudes towards brand extensions in a survey commissioned by Ventura. The Brand Finance Report for 1999 provides interesting reading on brand values and the overall performance of companies last year. In addition, there are a collection of shorter reports on various new branding issues and abstracts of articles on the topic.

The purpose of this research is a preliminary selection of wing section, which would be the best suited for PW-100 – a MALE class UAV of 600 kg weight. PW-100 will be used as a testing platform in different institutions such as research institutes, industry research centers or universities of technology (phase 1) to enable the in-flight testing of various on-board systems (mobile radars, thermovision sensors, chemical sensors, antennas, teledetection systems and others). Untypical layout of PW-100 resulted from the plans of further development of this configuration for a military application.

Important role in the research described in this paper plays the selection of main wing section to fulfil the preliminary requirements regarding maximum lift coefficient, minimum drag, aerodynamic efficiency etc. Two different wing sections (R1082 and SA19) were tested in wind tunnel, both with flaps deflected at the range of 0°-30°. Experimental measurements were performed in the low turbulence wind tunnel with closed test section of 45 cm × 35 cm. Numerical simulations of the flow around the wing sections were performed using MSES code. Boundary conditions were assumed basing on the typical mission of PW-100 for flight altitude around 9,000 m, speed of 110 km/h what results in Re = 956,000.

Lift coefficients obtained from both experimental and numerical methods for single slatted airfoil SA19 are much higher than that of get for Ronch R1082 airfoil. PW-100 aircraft with SA19 airfoils will be able to be trimmed and fly at any altitude up to 9,000 m and with an arbitrary weight up to 600 kg. Aerodynamic characteristics of SA19 remain smoother and more predictable than that of R1082 airfoil. The very promising properties of SA19 airfoil are well known to the authors since the beginning of last decade when PW team worked together with IAI team on CAPECON project and now it was fully confirmed by this research.

It was confirmed that selection of the proper wing section for the special mission performed by UAV is of the highest importance decision to be taken at the preliminary design phase. Because there is a limited access to the base of technical parameters in many different UAVs classes and the classical analysis of trends cannot be fully applied, the wing section analysis, either experimental or numerical, must be performed. The situation is much worse than in the case of manned aircrafts because most of the modern UAVs are made of carbon or glass fiber, and therefore, there is no chance for analysis of trends.

This paper presents a very efficient method of assessing the influence of wing section on aircraft performance adopted for MALE class UAV, especially in an early stage of preliminary design process. The assessment is built mainly on three requirements: Maximum 2D lift coefficient for take-off configuration with flap deflected on 20 degrees should be greater than 2.4. Endurance factor CL1.5/CD for loitering conditions (Ma = 0.5 and CD0 = 0.008) should be greater than 110. The relative wing section thickness should be greater/equal than 19 per cent (it is required for high volume fuel tank located in the wings).

The purpose of this paper is to present an approach to a polar graph measurement by a flight testing technique and to propose a baseline research method for future tests of UAV polar graphs. The method presented can be used to demonstrate a conceptual and preliminary design process using a scaled, unmanned configuration. This shows how results of experimental flight tests using a scaled flying airframe may be described and analysed before manufacturing the full scale aircraft.

During the research, the flight tests were conducted for two aerodynamic configurations of a small UAV. This allowed the investigation of the influence of winglets and classic vertical stabilizers on the platform stability, performance and therefore polar graphs of a small unmanned aircraft.

A methodology of flight tests for the assessment of a small UAV’s polar graph has been proposed, performed and assessed. Two aerodynamic configurations were tested, and it was found that directional stability had a large influence on the UAV’s performance. A correlation between the speed and inclination of the altitude graph was found – i.e. the higher the flight speed, the steeper the altitude graph (higher descent speed, steeper flight path angle). This could be considered as a basic verification that the recorded data have a physical sense.

The polar graph and therefore glide ratio of the aircraft is a major factor for determining its performance and power required for flight. Using the right flight test procedure can speed-up the process of measuring glide ratio, making it easier, faster, robust, more effective and accurate in future research of novel, especially unorthodox configurations. This paper also can be useful for the proper selection of requirements and preliminary design parameters for making the design process more economically effective.

This paper presents a very efficient method of assessing the design parameters of UAVs, especially the polar graph, in an early stage of the design process. Aircraft designers and producers have been widely performing flight testing for years. However, these procedures and practical customs are usually not wide spread and very often are treated as the company’s “know how”. Results presented in this paper are original, relatively easily be repeated and checked. They may be used either by professionals, highly motivated individuals and representatives of small companies or also by ambitious amateurs.

Using unpublished time‐series data for three specific age/gender groups, we first determine the percentage of female employment to total employment for nine sectors of the U.S. economy. Second, we estimate the cyclical change in hours of employment for each age/gender group within each sector. Third, we estimate the cyclical behavior of the nominal wage for each sectoral gender group. The paper’s evidence does not support, in general, a more cyclical response of female hours worked in the service‐producing sectors that are dominated by women. We find partial evidence that hours worked by men are more cyclical compared with hours worked by women in the male‐dominated goods‐producing sectors. Given the evidence of no pronounced difference in the cyclical behavior of hours and wages for men and women, the business cycle is gender‐neutral.That is, the elastic female labor supply is washed out over the business cycle across major sectors of the U.S. Economy. Observational evidence suggests supply‐side and structural factors in the economy have attenuated the business cycle, especially in the service‐producing sectors.

A survey was carried out of users, and potential users of the BBC Scotland Information Research Library services. Two postal questionnaires were sent out in the summer of 1995 to more than 100 individuals and organisations in Scotland. Based upon a 50% response rate, various conclusions could be drawn. Internal respondents were very satisfied with the services they currently received, but were, unsurprisingly, unwilling to pay significant sums to receive the services. There is some potential interest from outside the BBC in the Library's Events Guide. The exercise was undertaken both to assess the potential market for the Events Guide and to raise awareness generally of the Library's services. The results provide valuable pointers to how the BBC Scotland library services can develop, and, in time, the survey may turn out to have been a valuable marketing tool in its own right.

This paper aims to clarify the character of globalization, to identify the changes it brings to structures of governance, and to consider ways in which these arrangements could be made to serve a good (more global) society.

This essay takes a reflective approach.

The paper considers the rules and regulatory processes that govern today's more global world. The first step in the analysis identifies globalization as a trend whereby people's lives become more interconnected on a planetary scale. The second section describes the institutional apparatuses through which global issues are governed. Global governance is seen to take shape not as a “world government”, but as a complex array of regulatory networks that span local to global scales and also combine public and private sectors. The third section assesses the normative values that this “networked” and “polycentric” governance of global affairs might serve. Both an earlier “neoliberal” design of global governance and a currently prevailing “social market” paradigm are critiqued. An alternative vision of global social and ecological democracy is offered as a more promising road to a good society in the contemporary more global world.

The paper suggests alternative guiding principles for governance of today's more global society, including the role of corporations in it.

The paper suggests ways in which global governance can deliver social justice, ecological sustainability and democracy along with material prosperity.

The paper consolidates a conception of post‐statist governance that can aid researchers and practitioners alike in mapping the processes of contemporary policymaking. The normative framework presented can, moreover, help to clarify the objectives that citizens of a more global world would wish regulation to provide.

It will be recalled that the last monograph treated the significance of the collective agreement in society. If solely a function in society, (though having a legal basis), were to be attributed to the collective agreement, this would mean that no rights or obligations whatsoever would be created between the parties to it. This is not so in practice. It is of course a fact that no legally enforceable rights and obligations normally accrue, and as already indicated, those are moral ones and are only enforceable in honour, i.e. a gentleman's agreement. Nevertheless, this does not necessarily mean that the collective agreement has no juridical significance. Even agreements which are binding in honour only, as for example the kind of agreement found in Balfour v. Balfour, have a known juridical nature. Furthermore, though the collective agreement is only binding in honour, its incorporation into the individual contract of employment makes its terms legally enforceable even though recourse to the courts is seldom had. As a source of rights and obligations of considerable importance the collective agreement must therefore have some juridical significance and cannot remain entirely in the realms of society.

Dual-rotor wind turbines (DRWTs) are a novel type of wind turbines that can capture more power than their single-rotor counterparts. Because their surrounding flow fields are complex, evaluating a DRWT design requires accurate predictive simulations, which incur high computational costs. Currently, there does not exist a design optimization framework for DRWTs. Since the design optimization of DRWTs requires numerous model evaluations, the purpose of this paper is to identify computationally efficient design approaches.

Several algorithms are compared for the design optimization of DRWTs. The algorithms vary widely in approaches and include a direct derivative-free method, as well as three surrogate-based optimization methods, two approximation-based approaches and one variable-fidelity approach with coarse discretization low-fidelity models.

The proposed variable-fidelity method required significantly lower computational cost than the derivative-free and approximation-based methods. Large computational savings come from using the time-consuming high-fidelity simulations sparingly and performing the majority of the design space search using the fast variable-fidelity models.

Due the complex simulations and the large number of designable parameters, the design of DRWTs require the use of numerical optimization algorithms. This work presents a novel and efficient design optimization framework for DRWTs using computationally intensive simulations and variable-fidelity optimization techniques.