Ultimate capacity of blast loaded structures common to chemical plants

There has been a great deal of investment in development of design criteria and design and construction of heavily reinforced, blast-resistant control rooms. This remains the best option for protective construction against severe blast loading experienced close in to a vapor cloud or other explosion hazard. However, most structures encountered at chemical plants and contemplated for future construction are conventional steel frame, metal clad buildings. In this paper we look closely at the response of such buildings to explosion loads and their ability to undergo large deformations without structural failure. The types of structural elements evaluated include metal decking of various gauge and shape along with a variety of girt and purlin sections. Building frames or bents are also evaluated, although the date base for these is much more limited. The work is based on observations made during investigations of large explosion accidents along with analytical predictions and test measurements. To conclude, we offer specific design criteria and connection recommendations for enhancing the overall strength of a building through the use of conventional components in unconventional construction.     

Do satisfying walking and cycling trips result in more future trips with active travel modes? An exploratory study

Previous studies have indicated that travel satisfaction - the experienced emotions during, and cognitive evaluation of, a trip - can be affected by travel mode choice and other trip characteristics. However, as satisfactory trips might improve a person's attitude towards the used mode, persons may be more likely to use that same mode for future trips of the same kind. Hence, a cyclical process between travel mode choice and travel satisfaction might occur. In this paper we begin to analyse this process—using a structural equation modelling approach on cross-sectional data—for people who engage in walking and cycling for leisure trips in the Belgian city of Ghent. The focus on walking and cycling reflects recent studies indicating that active travel is often associated with the highest levels of travel satisfaction. Results of this exploratory analysis offer tentative support for the idea of a cyclical process: the evaluation of walking and cycling trips positively affects the respondents' attitude towards the respective mode, which in turn has a positive effect on choosing that mode.     

What determines international tourist arrivals in India?

Using data for 18 major tourist originating countries to India from 2001 to 2015, this study examines the major determinants of international tourist arrivals in India. The results indicate that past experiences of the tourists, per capita income in the tourist originating country, relative costs of living between India and the country of origin, and the level of infrastructure development in India are key determinants of international tourist arrivals in India. Furthermore, both transportation and communication infrastructure are important in attracting tourists to India. In particular, evidence suggests that availability of road and air network and telephone connections has favourable impacts on international tourist arrivals in India. These results are robust to the inclusion of additional variables. These results have important policy implications.     

The Benefit Function Approach to Modeling Price-Dependent Demand Systems: An Application of Duality Theory

In this article, we advocate more extensive use of the benefit function in specifying price-dependent or inverse demand models. We demonstrate how duality theory may be used to establish the interrelationships between the Marshallian (or Hicksian) inverse demands and Luenberger's adjusted price functions, allowing estimable inverse demands to be derived directly from a benefit function. We estimate two systems of inverse demands for Japanese quarterly fish consumption. Results indicate that the procedures and methods employed here appear promising, and may prove beneficial for quantity and welfare analysis when modeling systems of inverse demand functions.     

Farmland for tomorrow in densely populated areas

The paper describes the results of a research that aimed to come up with a well structured method to estimate future farmland requirements in densely populated areas. By using in depth interviews, scenario analysis and strategic orientation rounds, a method is developed to support policy optimization and to explore alternative future developments. The method is applied to the case of agriculture in the Flemish part of Belgium to show the feasibility of the model and to provide input for the discussion among policy makers in Flanders. The research results can be used by policy makers to build a new Spatial Plan Flanders for the period 2007–2013.     

Long-Term Productivity and Factor Demand in the Canadian Pulp and Paper Industry

The long-term structure of production, factor demand and factor productivity in the Canadian pulp and paper industry was studied for the period 1956 to 1982. A four input (labor, capital, material and energy) nonhomothetic translog cost function was used for the purpose. Least-cost combinations of the four factors were obtained by imbedding an interrelated dynamic adjustment process. These least-cost paths, from which the cyclical fluctuations due to business turns were filtered out, were then used to derive the long-term productivity of each input. Long-term elasticities of substitution and demand were also computed. Long-term and short-term results were compared. Important findings of the study were: (i) the long-term structure of production of the industry can be represented by the nomothetic version of the translog cost function, (ii) the long-term technological progress in the industry is slow despite evidence of some economies of scale in production, (iii) all factors of production in the industry are long-run substitutes despite short-run complementarities between some factors of production, (iv) each input was observed to be misallocated during the period of study as compared to the least-cost allocations, (v) observed productivity growth of capital, labor and energy declined during the seventies and early eighties, as compared to growth in the sixties, but growth in their long-run productivities did not, (vi) though both observed and long-run productivities of raw material declined the rate of decline was lower on the long-run path, and (vii) price increases in the pulp and paper industry after 1971 could have been lower than what was actually experienced if the industry could change with economic circumstances more rapidly. La structure à long terme de production, de facteur de demande et de facteur de productivité dans l'industrie canadienne de putpe et de papier est étudiée pour la période de 1956 à 1982. Une fonction de coût “nonhomothetic translog” avec quatre entrées (la main-d'oeuvre, le capital, le matériel et l‘énergie) est utilisée pour cette étude. Les combinaisons les moins chères des quatre facteurs sont obtenues en incluant un ajustement dynamique du processus d'interaction. Ces chemins les moins chers, desquels les fluctuations conjoncturelles dues aux changements d'affaires sont enlevées, sont utilisés pour dériver la productivité à long terme de chaque entrée. Les élasticités à long terme de substitution et de demande sont aussi calculées. Les résultats à long terme et ceux à court terme sont comparés. Les découvertes importantes de cette étude sont: (i) la structure à long terme de production de l’-industrie peut être représentée par la version “homothetic” de la fonction de coût “translog,” (ii) le progrès technologique à long terme dans l'industrie est lent malgré l‘évidence de certaines économies par la production à grande échelle, (iii) tous les facteurs de production dans l'industrie sont des substituts à long terme malgré les complémentarités à court terme parmi les facteurs de production, (iv) chaque entrée était allouée au mauvais endroit pendant la période d’étude à comparaison des allocations les moins chères, (v) la croissance de productivité observée de capital, de main-d'oeuvre et d‘énergie a diminué pendant les années soixante-dix et au début des années quatre-vingts, à comparaison de la croissance dans les années soixante, mais la croissance de leurs productivités à long terme n'a pas diminué, (vi) bien que les productivités observées et à long terme de matières premières ont diminué, les taux de diminution sont plus bas sur le chemin à long terme, et (vii) les augmentations de prix dans l'industrie de pulpe et de papier après 1971 auraient pu être plus bas qu'on n'a expérimenté si l'industrie était capable de changer plus rapidement selon les circonstances économiques.     

Ten years after UNCOD

Ten years ago the United Nations Conference on Desertification (UNCOD) formally recognized an intricate process of land degradation that had been plaguing mankind for thousands of years. The term desertification was given to this process. In earlier times man adapted to desertification by moving to better places. This is rarely possible today and communities are more often forced to suffer the consequences — in the worst cases, starvation and uncontrolled migration into camps and urban slums. UNEP is charged with following up the implementation of UNCOD's Plan of Action to Combat Desertification. This article looks at UNCOD and gives an overview of what UNEP has been doing — and plans to do — to combat desertification.     

Qualitätserwartungen und ethischer Anspruch bei der Lektüre von Blogs und von Tageszeitungen

Besides classical journalistic products, media users increasingly tend to read texts on the internet published by other users, as in weblogs. How do users navigate among these offers, how do they evaluate the quality, and which standards in terms of media ethics do they apply when reading weblogs compared to newspaper articles? Two empirical studies address these questions. In a survey, 702 internet users rated their theoretical expectations in terms of journalistic quality and compliance with ethical standards, comparing weblogs and daily newspapers. In a consecutive 2 × 2 experimental design, 120 participants read a journalistic text with varying source information (weblog/daily newspaper) and varying degree of adherence to ethical standards (ethically questionable/neutral). Participants then rated the quality of the text and its ethical standards. Results indicate that daily newspapers more than blogs are expected to deliver journalistic quality. But when read, texts are evaluated according to their content rather than their source. Ethically questionable texts in newspapers are disapproved as much as ethically questionable blog postings.