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The use of indicators focused on management performance is relatively new and only really appeared in the past few decades. A relevant number of authors consider that their use is a key factor in project management. These measures should add value to one or more of the stakeholders. Project delivery and project management require different sets of metrics to monitor their successful progress. While the first relies on the characteristics of the specific project, the latter can be generalised, as the process is often similar across projects, regardless of their nature. In the literature review of this subject, most of the references are focused to particular aspects of the project management, such as earned value analysis, risks, project evaluation or maturity models. This paper describes a comprehensive set of performance indicators suitable for implementing any project management and project monitoring management activities. The significant collection of metrics identified in the research (over 300) form the basis of the methodology developed for this paper and based around the Delphi method. Using the Delphi technique, a dashboard of 26 indicators narrowed from the original 83 has been created after using three consultation rounds with a high level of consensus and a stable and homogeneous response from a panel of seven experts. This research had taken into account different ways to analyse this consensus and stability, selecting the one based on the coefficient of variation. Within The flexibility and customising capability of this set of indicators has been validated using a case study based on a consultancy project.

Biomass and carbon dioxide accumulated amounts have been estimated in two Pinus sylvestris and Quercus pyrenaica forests («Matas de Valsaín» and «Pinar de Valsaín», Segovia). Data obtained in samplings made by CIFOR-INIA for both species have been utilized in this study. For each species, three trees per diameter class were selected, being then felled and separated into their biomass fractions (stems, branches with diameter over 7 cm, branches with diameter between 2 and 7 cm and branches thinner than 2 cm). Every tree fraction was weighed at field. The stump of one tree per diameter class was also extracted and weighed. Dry weights were determined at the laboratory through a sample of each fraction, and linear regression models to relate dry biomass with diameter for each biomass fraction were fitted. Using these models, a biomass table was constructed to be applied to inventory data (number of trees per diameter class) for determining total biomass within the stands. The CO2 fixed per biomass unit was calculated through the ratio biomass/carbon. Balances of net CO2 fixation have been determined knowing the annual increment and annual extractions. Se ha realizado una estimación de la biomasa y del dióxido de carbono que hay acumulado en las masas de Pinus sylvestris y Quercus pyrenaica de los montes «Matas de Valsaín» y «Pinar de Valsaín» (Segovia). Para ello se han utilizado los datos de muestreos realizados por el CIFOR-INIA para ambas especies. Se eligen al menos tres pies por clase diamétrica, se apearon y se separaron en fracciones de biomasa (fuste, ramas de diámetro mayor de 7 cm, ramas de diámetro entre 2 y 7 cm, ramas menores de 2 cm) que se pesaron en campo. Se extrajo el tocón de un pie por clase diamétrica y se pesó en verde. En laboratorio se determinó el peso seco de las muestras y se hallaron modelos para las distintas fracciones que relacionasen la biomasa seca y con el diámetro. Con estos modelos se calcularon unos valores modulares que se aplicaron a los datos del número de pies, obtenidos de los inventarios, para estimar la biomasa total de los montes. El CO2 se estima mediante la relación entre el porcentaje de carbono en la biomasa seca y la cantidad de carbono en una molécula de CO2. Se han realizado balances de fijación neta de CO2 conociendo los crecimientos y las extracciones anuales.

A methodology for estimating total hicksian income in multiple-use forests is presented. The approach consistently incorporates commercial as well as non-commercial economic values and enables the measurement of national accounting aggregates taking into account variation in man-made and natural capital. Innovative solutions are developed (i) for the estimation of non-market values, such as recreation, where an attempt to determine exchange values has been made simulating markets, (ii) for timber, where standing timber valuation methods have been extended to cover uneven stands, and (iii) for carbon fixation valuation, where only permanently fixed carbon after 1990 has been taken into account. The methodology is applied to a multiple-use pinewood in the Guadarrama mountains, near Madrid (Spain). Timber, cattle grazing, hunting, recreation, carbon fixation and conservation values are measured and integrated in the accounting system, using primary microeconomic data from the case study. Results indicate the importance of non-commercial income, which accounts for 51% of the total income, and the social relevance of the analysed forest, implying that only 31% of the total income generated is appropriated by the forest owner.

Structural diversity is a good indicator of biodiversity and can be easily modified by silvicultural treatments, so it is a basic element on sustainable forest management. A revision about the analysis of the structural diversity in forests is carried out. There are two approaches to study the structural diversity in a forest: static and dynamic. Firstly the main indices that described the structure characteristics as a static point of view are described and discussed. Three structure characteristics of a stand are considered: spatial distribution, mixture and differentiation. Secondly, indices that describe the structural diversity as a whole are also analysed. These last indices include generally a component of dead wood. Finally, reported dynamic analyses are reviewed. The dynamic analysis is usually made through the study of the static indices development along the time. Three kind methodologies can be used: temporal plots located in stands of different phases of development, permanent plots, and growth models that simulate the stand structure. La estructura es un buen indicador de la biodiversidad del sistema y es fácilmente modif icable a través de la selvicultura, por lo que su adecuado conocimiento es indispensable para garantizar una gestión sostenible. En este trabajo se presenta una revisión sobre el análisis de la diversidad estructural en masas forestales. El estudio de la diversidad estructural de un bosque se puede abordar desde un punto de vista estático y dinámico. En primer lugar se describen y discuten los principales índices que caracterizan desde un punto de vista estático los tres aspectos de la estructura de un rodal: distribución espacial, diversidad y mezcla de especies y diferenciación. Para cada uno de estos tres aspectos se incluyen índices tanto espaciales como no espaciales. Posteriormente se analizan los índices de diversidad estructural conjunta, que valoran de manera global los tres aspectos de la estructura del rodal antes considerados, incluyendo en algunos casos una estimación de la madera muerta. Finalmente se revisan los trabajos que realizan un análisis dinámico de la diversidad estructural, generalmente basados en el estudio de la evolución en el tiempo de los índices estáticos. Se comentan las tres metodologías con las que se puede acometer este estudio: parcelas localizadas en las distintas fases de desarrollo del ciclo de la masa, parcelas permanentes y modelos de crecimiento que simulen la estructura del rodal.

Growth and yield models of silviculture applied to four site indices have been drawn up. The data were obtained in 72 plots, installed in 1965 in man made stands of Pinus halepensis Mill., and inventoried in 1965, 1975, 1980, 1988 y 1999. The site index was defined as the top height at age 80 and models were adjusted using the Richards function, obtaining four site qualities: 20, 17, 14 and 11. Following this, silvicultural production models, including two different thinning regimes, were developed for the two higher site qualities sites, with more productive interest (20 and 17) using a simulation with the Hart-Becking rate. For 11 and 14 site quality, only one moderate thinning regime was developed, bearing in mind their most important protection value. A partir de los datos obtenidos de 72 parcelas instaladas en 1965, en masas repobladas de Pinus halepensis, inventariadas en 1965, 1970, 1975, 1980, 1988 y 1999, se han elaborado modelos de crecimiento y producción de selvicultura encontrada para cuatro calidades de estación. Las curvas de calidad se han definido por la altura dominante alcanzada a los 80 años de edad y se han ajustado por el modelo de Richards, resultando las siguientes curvas: calidad 20, calidad 17, calidad 14 y calidad 11. Posteriormente se han elaborado modelos de producción de selvicultura variable incluyendo dos regímenes de claras, simulados a través de la variación del índice de Hart-Becking, para las calidades 20 y 17, que son las que presenta un mayor interés productivo. Para las calidades 14 y 11 se representan tablas con un único régimen moderado de claras, como corresponde a su mayor interés protector y su menor interés productivo.

Models for predicting parameter behaviour in the 2-parameter Weibull function in even-aged Pinus pinea stands of Valladolid (Spain) have been adjusted. From data out of 131 plots (20 trees per plot), real distribution parameters have been adjusted, using the percentile method, as well as non-linear regression. Next, predictive models of calculated parameters were adjusted, using stand variables. Parameter «b» is deeply related to mean cuadratic diameter (dg), while parameter «c», which was more difficult to model, is related to dg and other variable (Age or Canopy cover). Se han obtenido modelos explicativos de los parámetros de la función Weibull biparamétrica para modelizar las distribuciones diamétricas en masas regulares de Pinus pinea L. en la provincia de Valladolid (España). A partir de datos experimentales tomados en 131 parcelas (20 árboles/parcela), se han determinado inicialmente los parámetros de la distribución teórica ajustada a las distribuciones reales mediante el método de los percentiles y regresión no lineal. A continuación se han ajustado modelos lineales predictivos de los parámetros calculados, que incluyen variables de masa. El parámetro «b» se asocia muy estrechamente con el diámetro medio cuadrático (dg), mientras que el parámetro «c» presenta una mayor dificultad de ajuste, relacionándose con dg y una segunda variable (edad o fracción de cabida cubierta).

The use of herbicides in croplands forestation is needed in order to control weed competition for water, light and nutrients with tree seedlings. As selectivity of our forest species to herbicides and mode of aplication are scarcely known, we have studied the effect of three herbicides, hexazinone, pendimethalin and simazine on emergency and growth of Pinus halepensis and P. pinaster sowed in Forest-Pot during November and February inside a non-climatized greenhouse. Treatments were made in pine preemergency, one week after each sowing. Mean time emergency of two species of pine was minor in February than November sowing, however, thermic integrals (sumatory of temperatures > 5 °C since sowing time until mean time emergency) are not differents. Herbicide treatments did not influence emergency of pines, but later some of then caused mortality in seedlings. Hexazinone at doses of 1.5 kg a.i./ha caused mortalities of 84 % and 71 % in P. halepensis seedlings belonging to November and February sowings, respectively, and in P. pinaster, 93 % in seedlings of both sowings. Hexazinone at doses of 0.75 kg a.i/ha caused mortalities of 31 % and 18 % in P. halepensis seedlings belonging to November and February sowings, respectively, and 49 % and 61 %, in P. pinaster, respectively. Pendimethalin at 2 kg m.a./ha did not cause mortality in pine seedlings and simazine at 3 kg m.a./ha was tolerated for two pine species in February sowings, but in November sowings caused mortalities of 29 % in P. halepensis and 32 % in P. pinaster. El empleo de herbicidas en la forestación de tierras de cultivo se hace necesario para controlar la invasión de malas hierbas que compiten por agua, luz y nutrientes con los árboles que se intentan implantar. Como la selectividad de nuestras especies arbóreas a los herbicidas y su modo de aplicación son poco conocidos, se ha estudiado el efecto de tres herbicidas, hexazinona, pendimetalina y simazina sobre la emergencia y crecimiento de Pinus halepensis y P. pinaster que fueron sembrados en noviembre y en febrero en bandejas Forest-Pot. Los tratamientos se hicieron en preemergencia de los pinos, una semana después de cada siembra. El tiempo medio de emergencia de las dos especies fue menor en la siembra de febrero que en la de noviembre; sin embargo, no hubo diferencias en las integrales térmicas necesarias para alcanzar la emergencia. Los tratamientos herbicidas no afectaron a la germinación de los pinos, pero algunos causaron mortalidad cuando se alcanzó el estado de plántula. Dosis de 1,5 kg m.a./ha de hexazinona provocaron mortalidades del 84 % y 71 % en P. halepensis procedentes de las siembras de noviembre y febrero, respectivamente, y en P. pinaster del 93 % en ambas siembras. Este mismo herbicida a dosis de 0,75 kg m.a/ha determinó mortalidades del 31 % y 18 % en P. halepensis en las siembras de noviembre y febrero, respectivamente, y del 49 % y 61 %, en P. pinaster, respectivamente. Pendimetalina a 2 kg m.a./ha no causó mortalidad y simazina a 3 kg m.a./ha fue tolerada por las dos especies en las siembras de febrero, pero en las de noviembre provocó mortalidades del 29 % en P. halepensis y del 32 % en P. pinaster.

This study presents information about the ecology, typology, silviculture, production, dynamics and biodiversity of Scots pinewoods in Spain. The distribution and types of Scots pine stand are described, together with their most important climatic and edaphic aspects. Silvicultural aspects are considered including management objectives. Information is provided on the production potential of the stands, and a production table for the five site qualities defined is presented. The different stages of natural succession of the stands are described. Finally, there is brief mention of the effects of the silviculture on the biodiversity of these pinewoods. En este trabajo se presenta información sobre ecología, tipología, selvicultura, producción, dinámica y biodiversidad de los pinares de Pino silvestre en España. Inicialmente se realiza una descripción de la distribución y tipos de masa de Pino silvestre y de sus aspectos climáticos y edáficos más importantes. En segundo lugar se presenta una tipología de las masas naturales en la Península Ibérica. Posteriormente se tratan los aspectos más importantes de la selvicultura de la especie, incluyendo los objetivos de la ordenación de sus masas en España. En el apartado de producción se aporta información relativa de su producción potencial además de una tabla de producción para las cinco calidades de estación definidas en España. Se tratan las diferentes etapas de sucesión natural de las masas del pinar así como los tratamientos o prácticas selvícolas más comunes en España. Por último se hace una breve referencia de los efectos de la selvicultura aplicada en la biodiversidad de estas masas forestales.

Thinning of different intensity have been carried out on a Pinus pinaster plantation and results have been compared with that of a control treatment and one plot with the maximum biological density for this species and age. The experimental design consists of randomized blocks. Four inventories were made in summer in 1984, 1988, 1992 and 1996. With this information the volume, basal area and number of tree before thinning, thinning and after thinning were calculated. Standing biomass and mineral element concentration before thinning, biomass removed with thinning and standing biomass after thinning have been estimated trough inventories and subsequent determination of modular values (a sample with 100 trees). Litter fall represented by needles fall and dead branches has been measured as well as its evolution through the year on plots representing four different stand densities. En una repoblación de Pinus pinaster Ait. se ha aplicado un programa de claras de distinta intensidad, que se comparan con parcelas testigos y con una parcela en la que se alcanza la máxima densidad biológica para esta especie y edad. Se realizaron cuatro inventarios durante los veranos de 1984, 1988, 1992 y 1996. Con esta información se ha estimado el volumen maderable, el área basimétrica y el número de pies/ha antes de la clara, la masa extraída y la masa principal después de la clara. Mediante la medición de 100 árboles tipo se calcularon los valores modulares, por clases diamétricas de 5 cm de amplitud. Aplicando los valores modulares a la distribución diamétrica de cada tratamiento se ha estimado la biomasa aérea total antes de la clara, la biomasa aérea extraída por la clara y la biomasa aérea que persiste después de la clara. Por diferencia entre inventarios se ha estimado el crecimiento medio y corriente en diámetro, altura, área basimétrica y volumen, así como los crecimientos medio y corriente en biomasa aérea total para cada tratamiento. Se cuantificó el desfronde total en cada tratamiento selvícola. Para el caso de las acículas, por medio de una muestra de 50 contenedores, de 0,25 m2, se realizó su seguimiento mensual durante 10 años. El desfronde anual de ramas, piñas y corteza (conjuntamente) se cuantificó por medio de una muestra de 10 subparcelas de 4 m2. Por último se estimó la cantidad de acículas acumuladas sobre la superficie del suelo (barrujo) en 1985, 1988, 1992 y 1995 para cada tratamiento.

[ES] El trabajo presenta la aplicación de un sistema metodológico de cuentas del bosque que permite estimar la renta hicksiana generada en una tierra forestal con usos múltiples, incorporando tanto las rentas de bienes comerciales como no-comerciales. Se utiliza el valor real de mercado cuando está disponible y se simulan las condiciones de mercado cuando se presentan mediciones de bienes y servicios ambientales. El estudio de caso presentado es un bosque de pino silvestre (Pinus sylvestris L.) próximo a Madrid (España) con elevada calidad de la producción maderera y con una importante afluencia de visitantes para su disfrute recreativo. Los resultados revelan la notable importancia de las rentas ambientales así como el hecho de que el propietario privado del bosque recibe sólo una parte minoritaria del total de la renta generada en el pinar., [EN] The paper discusses in detail the application of a methodology capable to estimate the hicksian income generated in a multiple-use forest incorporating in a homogenous manner commercial and non-commercial incomes. Real market values are used where available and market conditions are simulated where goods and services are presently outside of markets. The case study is a Pinus silvestris L. area close to Madrid (Spain) with high value timber production and with an important affluence of recreational visitors. Results show the relevance of non-commercial incomes and the fact that the landowner appropriates only a minor part of the total income generated.

Results of three trials to improve the success in reforestation in agricultural lands with Pinus pinea plants are shown: plant technic production in nursery and field, mineral fertilisation and herbicide trials. The trial of plant quality (class and size of pot, fertilise rates and density of plant production) did not affect the survival of seedlings in nursery, but did in growth ones. In the biggest pots and with the biggest fertilise rates were obtain more growth of the plants (shoot and root height growth and dry matter weight). The results of the lost plant percentage in field are independent of the quality plant used, but bigger growth and better development are maintained in better quality plants before reforestation. In the trial of mineral fertilisation in field did not find significatives differences in the lost plants number for the two next years. The best results in height growth was obtain with Agroblen fertilise, and in second place with Agriform one. In the trial of herbicide used in reforestation did not find significatives differences in the lost plant number for the different kind and rates of herbicides. The herbaceous vegetation was controlled better by Hexacinona herbicide, even with the smaller rates (250 g/ha). The best height growth was obtained in the plant where was applied Velpar herbicide with rate from 500 to 350 g/ha. Se presentan los resultados de ensayos tendentes a mejorar el arraigo de plantas de Pinus pinea L. en repoblaciones de tierras agrarias abandonadas: técnicas de cultivo de planta en la fase de vivero y comprobación en campo, fertilización mineral en campo y empleo de herbicidas en repoblación. Los ensayos de técnicas de cultivo de planta realizados (tipo y tamaño de contenedor, dosis de fertilizante y densidad de producción de planta) no afectaron a la supervivencia de las plantas en el contenedor, pero sí al crecimiento de las mismas. Se ha obtenido mayor crecimiento de las plantas (longitud del tallo, raíz y peso seco aéreo y radical) en los contenedores de mayores dimensiones y con mayor concentración de fertilizante. Los resultados del porcentaje de marras en campo son independientes de la calidad de la planta utilizada, pero se mantienen los mayores crecimientos y desarrollo en las plantas consideradas de mejor calidad antes de la plantación. En el ensayo de fertilización mineral en campo no se encontraron diferencias significativas en el número de marras en los dos años siguientes a su plantación. Los mejores resultados en cuanto a crecimiento longitudinal de las plantas se obtuvieron con el fertilizante Agroblen, seguido de Agriform. En el ensayo de empleo de herbicidas en repoblaciones tampoco se encontraron diferencias significativas en el número de marras para los diferentes tipos y dosis de herbicidas utilizados. La hexacinona es el herbicida que ejerce un mejor control de la vegetación herbácea, aún con las dosis más pequeñas (250 g/ha). Los crecimientos longitudinales mayores se han obtenido en las plantas donde se aplicó el herbicida Velpar con las dosis de 500 y 350 g/ha.

The extraordinary damage caused by snow on January 1996 in Scots pine stands in the Sistema Central (Central Spain) are analysed. Data from two thinning experiences carried out in 44 and 60 years old stands have been used. Damage was greater in the crown thinning and control treatment (no thinning plots), compared with low thinning plots. Results clearly show a decrease on snow damage with increasing low thinning intensity. The effects of low thinning on stand stability is related with the lower growing stock, the removal of smaller and suppresed trees, and the lower risk of damage of the remaining stand. The individual susceptibility to snow damage decreases with decreasing height-diameter ratio, increasing diameter, and increasing lenght of green crown. Se presenta un análisis de los factores que influyen en los daños producidos por el temporal de nieve del invierno de 1996. La evaluación se ha realizado a partir de los datos obtenidos en dos ensayos de claras en masas de Pinus sylvestris L. en el Sistema Central plantados en 1970 y 1991, que constan de tres bloques y cuatro o cinco tratamientos de claras. En una de las experiencias se han ensayado distintas intensidades de claras bajas, y en la otra distintos tipos de claras. Los resultados muestran que los mayores daños se producen en las masas en las que se han realizado claras altas, seguidas por aquellas en las que no se han realizado claras. Las claras bajas y mixtas favorecen la estabilidad de la masa, disminuyendo los daños a medida que aumenta la intensidad del régimen de claras aplicado. El efecto positivo de las claras bajas y mixtas sobre la estabilidad de la masa, se debe a la menor densidad de la masa principal después de la clara, a la eliminación de los pies más susceptibles a ser dañados, y al aumento de la estabilidad individual a través de la menor esbeltez, mayor diámetro y mayor longitud de copa viva.

Se presenta en este trabajo resultados de eficacia computacional de técnicas elemento a elemento de resolución de sistemas de ecuaciones asociados a métodos de elementos finitos adaptativos de refinamiento de mallado, en los problemas de elasticidad, plana y conveccióndifusión en 2-D. Para el problema simétrico de elasticidad plana se exponen resultados comparativos obtenidos mediante el método de Gradiente Conjugado con precondicionadores Diagonal, Cholesky y Crout. El problema de convección-difusión no simétrico se aborda con métodos de Regularización Parabólica combinados con la técnica de Aceleración por Relsjsvión y métodos derivados del Gradiente Conjugado. Asimismo se presenta la experiencia de aplicar el método Multimalla considerando esquemas elemento a elemento en las iteraciones de suavizado y en la resolución del sistema en la primera malla. Este trabajo está basado en el estudio desarrollado en Montero.

The first example of hemoglobin Suresnes, α2 141 (HC3) Arg → His β2, has recently been reported by Poyart et al (1). Hb Suresnes was detected by electrophoresis in a 6 year old boy who was found by routine hematological examination to have an abnormal RBC count and Hb concentration. The propositus and the two other members of the family who also had the variant did not show any clinical symptoms.

Hemoglobin New York was first described by Ranney et al. (1) in a Chinese American family. It was also reported in Chinese subjects in Taiwan by Blackwell et al. (2).

En este trabajo se presentan formulaciones implícitas y explícitas para la resolución numérica del problema evolutivo de convección-difusión en 2-D, basadas en el método de las características. Se aborda un estudio comparativo sobre el comportamiento numérico de las distintas formulaciones propuestas. Se realizan diferentes aplicaciones numéricas utilizando varios indicadores de error para la resolución del problema mediante el método de elementos finitos adaptativo de refinamiento de mallado. Para la obtención directa de la solución estaciona~ias e combinan las técnicas adaptativas con el método de la difusión artificial. Este trabajo está basado e,n el estudio desarrollado en [13].

A yield model was developed to simulate silviculture alternatives for Pinus pinea L. in north-east Spain (Catalonia). The model uses several functions to estimate the main silvicultural parameters at stand level and a disaggregation system to predict diameter distributions. From a network of 75 temporary plots a system of equations to predict stand variables was simultaneously fitted for two stand density types, namely low and high density stands, using the three- stage least-squares method (3SLS). The diameter distributions were estimated by the Weibull distribution function using the parameter recovery method (PRM) and the method of moments. Based on this yield model, two silviculture alternatives were simulated for each stand density type and site class, resulting in 16 silviculture scenarios. The yield model and silviculture alternatives offer a management tool and a guide for the sustainable forest management of even- aged Pinus pinea forests in this region.

We estimate the private net benefits from afforesting marginal shrubland and cropland with cork oaks at two Spanish cork oak sites, Aljibe and Gavarres, in different time horizon frames. The analysis integrates market and nonmarket (landowner amenity) private capital incomes, including government afforestation grants. We apply cost-benefit analysis techniques for estimating the investment present value in the periods analyzed, taking residual values of cork oak woodland into account. The results show that the profitability rate of cork oak afforestation strongly depends on government subsidies. The value of private amenities, at least in Aljibe, seems to be positively affected by the forest area's share of the total estate surface. Thus, an increase in the afforested area would enhance the private amenity annual income with respect to maintaining the original property land's treeless uses. A higher level of private amenities attached to the forest area may imply a reduction in government grants for encouraging cork oak afforestation.

This paper introduces the concept of scale into the morphological indicators. Morphological indicators were first touched in references [1] and [2], but it was in reference [3] that their full potential was first established. Morphological indicators are dimensionless numbers that represent a physical property of structures. The two most important morphological indicators are the indicator of volume and the indicator of displacement. In this paper we will work with the indicator of volume W. It is the volume of an isomorphic structure with unit span, with at least one section of each element dimensioned on its unit allowable stress, subjected to a load system with a unit resultant. This number decouples the efficiency of a structure from its scale. Indeed, in its simplest formulation, the indicator of volume only depends on the slenderness of the rectangle in which the structure is inscribed. If phenomena like buckling, self weight and deck weight (for trusses) are taken into account [4], the indicator of volume will no longer be independant of the scale of the problem. However, the explicit study of the influence of the scale on the optimal design has not been performed yet. In this paper, three phenomena that are influenced by the scale are studied: buckling, self weight and deck weight. Buckling sensitivity is proportional to the square root of the span L. Self weight contributions are proportional to the span L and deck weight is also proportional to the span L, from the moment the height of the deck reaches its maximum height. Their effect is illustrated with two examples: a beam and a two mesh warren truss. The value of their indicator of volume increases as expected with span, until a limit span is reached. One way to design better warren trusses is to let the mesh number vary. This will generate better results, because buckling lengths will decrease as well as deck spans. An alternative lay-out is the so-called multiwarren, where the deck beams of the master warren is a warren truss. This process canbe repeated until deck contributions are minimised. This yields better results than simply varying the mesh numbers of a warren truss. The conclusion of the examples is that scale effects have an important impact on the optimal design. Future work should incorporate other important phenomena, like dynamics [5] and the weight of connections. In stead of solving buckling globally (through the choice of a topology), it can also be solved locally (by using cable stayed columns [5]). References 1 H. Cox, "The Design of Structures of Least Weight", Pergamon Press, Oxford, 1965. 2 W.S. Hemp, "Optimum Structures", Clarendon, 1973. 3 Ph. Samyn, "Étude Comparée du Volume et du Déplacement de Structures Isostatiques Bidimensionnelles sous Charges Verticales entre Deux Appuis", Ph.D Thesis, Université de Liège, Belgium, 1999. 4 P. Latteur, "Optimisation et prédimensionnement des treillis, arcs, poutres et câbles sur base d'indicateurs morphologiques", Ph.D Thesis, Vrije Universiteit Brussel, Belgium, 2000. 5 J. Van Steirteghem, "A Contribution to the theory of Morphological Indicators: (In)stabilities and Dynamics", Ph.D Thesis, Vrije Universiteit Brussel, Belgium, 2006.

The earthquake ground shaking is usually presented in the form of a response spectrum of acceleration or displacement. The spectrum used as input to equivalent lateral force or spectral modal methods of analysis is usually obtained by scaling an elastic spectrum by factors that account for, amongst other phenomena, the influence of inelastic structural response. However there are problems in which the simulation of structural response using a scaled elastic response spectrum is not considered appropriate, and full dynamic analysis is required (buildings designed for a high degree of ductility ; structures with configuration in plan or elevation that is highly irregular ; structures for which higher modes are likely to be excited ; critical structures, the failure of which would cause unacceptable harm or disruption – dams, nuclear Paper 244 Real Earthquake Accelograms as Input for Seismic Analysis D. Cizmar† , J. Radic† , D. Mestrovic† and A. Nizic‡ † Department for structures University of Zagreb, Croatia ‡ Lehrstul für Massivbau Technical University of Munich, Germany © Civil-Comp Press, 2006. Proceedings of the Eighth International Conference on Computational Structures Technology, B.H.V. Topping, G. Montero and R. Montenegro, (Editors), Civil-Comp Press, Stirlingshire, Scotland. 2 power plants etc). On the other hand there is open question if scaled elastic response spectrum are sufficient for regular buildings because as earthquake databases are being updated the spectra curves are subject to change as well.

We provide a fast algorithm to compute arbitrarily many nodes and weights for rational Gauss-Chebyshev quadrature formulas integrating exactly in spaces of rational functions with arbitrary complex poles outside [-1, 1]. This algorithm is based on the derivation of explicit expressions for the Chebyshev orthogonal rational functions. ispartof: Proceedings of the Fifth International Conference on Engineering Computational Technology ispartof: Fifth International Conference on Engineering Computational Technology location:Las Palmas de Gran Canaria, Spain date:12 Sep - 15 Sep 2006 status: published

In case of dynamic measurements under moving load when we are recording displacements instead of accelerations or velocities dominant values belong to static displacements. Performing discrete Fourier transforms static displacements due to moving load show as large amplitudes in very low frequencies. A general filtration rule that would eliminate the influence of recording the static displacement along with dynamic vibrations could not be found in all examples and a conclusion was drawn that in order to perform frequency domain analysis static displacements have to be eliminated on the signal level. Two examples have been devised in order to demonstrate the necessary procedures for determining the eigenfrequency of a beam structure from laser measured dynamic displacements.

In this paper a numerical stability analysis of creeping beam structures is presented. A numerical algorithm using one dimensional spatial beam finite element is developed. Beam members are supposed to be straight and prismatic. Spatial displacements and rotations are allowed to be large but strains are assumed to be small. The corresponding equilibrium equations are formulated in the framework of Eulerian description, using the virtual work principle. Euler-Bernoully beam theory for flexure is assumed as well as Saint-Venant theory for torsion. In contrast to conventional Eulerian formulation, which is linear on element level, in this paper an additional nonlinear part of stiffness matrix is evaluated in order to model Wagner effect.