The Question of Generation Adequacy in Liberalised Electricity Markets

This paper presents an overview of the reasons why unregulated markets for the production of electricity cannot be expected to invest sufficiently in generation capacity on a continuous basis. Although it can be shown that periodic price spikes should provide generation companies with sufficient investment incentives in theory, there are a number of probable causes of market failure. A likely result is the development of investment cycles that may affect the adequacy of capacity. The experience in California shows the great social costs associated with an episode of scarce generation capacity. Another disadvantage is that generation companies can manipulate price spikes. This would result in large transfers of income from consumers to producers and reduce the operational reliability of electricity supply during these price spikes. We end this paper by outlining several methods that have been proposed to stabilise the market, which provide better incentives to generation companies and consumers alike.Generation adequacy, Liberalised electricity market

On charisma and need for leadership

Some scholars have argued and found that the relationship between transformational leadership and outcomes can be moderated by subordinate or situational characteristics (e.g. Bass and Avolio, 1990; Podsakoff, MacKenzie, and Bommer, 1995). Still, there is insufficient evidence on this issue. In this paper we examine need for leadership (De Vries, 1997) as a moderator of the relation between a measure for charismatic leadership (Bass, 1985a; Den Hartog, Koopman & Van Muijen, 1994) and subordinate outcomes. Need for leadership is found to moderate the relation between charismatic leadership and three out of four criteria. Furthermore, we examine the relation between charismatic leadership and need for leadership. While it has been asserted that transformational leaders are able to empower and develop subordinates to become leaders themselves (e.g. Bass and Avolio, 1990; Kuhnert, 1994; Yammarino, 1994) we find a positive relationship between charismatic leadership and need for leadership, which suggests that subordinates are more, instead of less, dependent when a charismatic leader is present.leadership;character trait

Designing with constraints - Towards mass customization in the housing industry

Mass customization, while common in other industries, has yet to find widespread adoption in the housing industry. Current methods of mass customization are either labour-intensive or allow only a limited degree of freedom. In this paper, we look at a method of mass customization that allows buyers to make modifications to the design of their house, after which the new design is automatically checked against building regulations and the architect’s requirements

On charisma and need for leadership

Some scholars have argued and found that the relationship between transformational leadership and outcomes can be moderated by subordinate or situational characteristics (e.g. Bass and Avolio, 1990; Podsakoff, MacKenzie, and Bommer, 1995). Still, there is insufficient evidence on this issue. In this paper we examine need for leadership (De Vries, 1997) as a moderator of the relation between a measure for charismatic leadership (Bass, 1985a; Den Hartog, Koopman & Van Muijen, 1994) and subordinate outcomes. Need for leadership is found to moderate the relation between charismatic leadership and three out of four criteria. Furthermore, we examine the relation between charismatic leadership and need for leadership. While it has been asserted that transformational leaders are able to empower and develop subordinates to become leaders themselves (e.g. Bass and Avolio, 1990; Kuhnert, 1994; Yammarino, 1994) we find a positive relationship between charismatic leadership and need for leadership, which suggests that subordinates are more, instead of less, dependent when a charismatic leader is present.

Check-mate: Automatic constraint checking of IFC models

Building Information Models (BIMs) allow for computationally checking whether a building design satisfies all the building codes, requirements, etc. if constraints are included in the model. One application for this is mass customization in the housing sector, when clients modify the design without help from the architect. This paper describes the technical aspects of checking constraints on a building model. Specifically, we look at the feasibility of checking constraints on an IFC model by creating a prototype in which constraints can be entered and checked on an imported IFC model. Conclusions are drawn on the suitability of the IFC model and how IFC can be extended or adjusted to support constraint checking

Selecting informative food items for compiling food-frequency questionnaires: comparison of procedures

The authors automated the selection of foods in a computer system that compiles and processes tailored FFQ. For the selection of food items, several methods are available. The aim of the present study was to compare food lists made by MOM2, which identifies food items with highest between-person variance in intake of the nutrients of interest without taking other items into account, with food lists made by forward regression. The name MOM2 refers to the variance, which is the second moment of the nutrient intake distribution. Food items were selected for the nutrients of interest from 2 d of recorded intake in 3524 adults aged 25–65 years. Food lists by 80 % MOM2 were compared to those by 80 % explained variance for regression on differences between the number and type of food items, and were evaluated on (1) the percentage of explained variance and (2) percentage contribution to population intake computed for the selected items on the food list. MOM2 selected the same food items for Ca, a few more for fat and vitamin C, and a few less for carbohydrates and dietary fibre than forward regression. Food lists by MOM2 based on 80 % of variance in intake covered 75–87 % of explained variance for different nutrients by regression and contributed 53–75 % to total population intake. Concluding, for developing food lists of FFQ, it appears sufficient to select food items based on the contribution to variance in nutrient intake without taking covariance into accoun

Triggering synchronized oscillations through arbitrarily weak diversity in close-to-threshold excitable media

It is shown that arbitrarily weak (frozen) heterogeneity can induce global synchronized oscillations in excitable media close to threshold. The work is carried out on networks of coupled van der Pol-FitzHugh-Nagumo oscillators. The result is shown to be robust against the presence of internal dynamical noise.Comment: 4 pages (RevTeX 3 style), 5 EPS figures, submitted to Phys. Rev. E (16 aug 2001