The Role of the TPA-70 Gateway-Network in Promoting Transborder Data Flow of Scientific Information in an International Setting

This paper describes the recently developed "TPA-70 gateway-network" of the International Institute for Applied Systems Analysis (IIASA) in Austria, and of the Institute for Computerization and Automation of the Hungarian Academy of Sciences (SZTAKI) in Hungary, and its promoting role in the on-line exchange of scientific information among national and international institutes and organizations. It presents a short overview of the major categories of transborder data flows relevant to IIASA's work, and how the gateway-network handles them. Finally, some operational and technical aspects of this East-West network of gateways are discussed

Do the C-H Bonds Contribute to the Stabilization Energy of Benzene?

The stabilization energy of benzene (SE) is proposed to be · calculated from the increments of heats of formation in the homologous series of conjugated polyenes. In this way 19.7 and 23.0 kcal/mol* are derived for $E, when benzene is compared to trans and cis type polyenes, respectively. A comparison of the estimated C-C bond energy of benzene to that of olefins leads to the conclusion that C-C bonds are responsible for only about 2/3 of SE. It is suggested that the rest of SE is connected with the difference in strength of the aromatic and olefinic C-H bonds

Process Analysis and Synthesis

Contains reports on two research projects

Discrete vs. Discretized Growth Discretized Fabrication of Geometries Generated with Cellular Growth Simulations

Discrete computational growth simulations, such as Cellular Automata of Diffusion Limited Aggregation, appear often to be difficult to use for architectural design as their geometric outcomes tend to be difficult to control. On the contrary, free-form growth simulations such as Differential Growth or cell-based growth algorithms produce highly complex geometries that are difficult to construct at a larger scale. We, therefore, propose a methodology of discretized free-form Cellular Growth algorithms in order to utilize the emerging qualities of growth simulations for a feasible architectural design. The methodology has been tested within the framework of a workshop and resulted in the efficient construction of a large physical prototype

Promotion of East-West Computer Communication in IIASA's International Environment and the Hungarian Case Study

This paper describes the functions of the "IIASA Gateway" as seen by a "typical user", IIASA's Hungarian National Member Organization

Taking the pulse of snowmelt: in situ sensors reveal seasonal, event and diurnal patterns of nitrate and dissolved organic matter variability in an upland forest stream

Highly resolved time series data are useful to accurately identify the timing, rate, and magnitude of solute transport in streams during hydrologically dynamic periods such as snowmelt. We used in situ optical sensors for nitrate (NO3 −) and chromophoric dissolved organic matter fluorescence (FDOM) to measure surface water concentrations at 30 min intervals over the snowmelt period (March 21–May 13, 2009) at a 40.5 hectare forested watershed at Sleepers River, Vermont. We also collected discrete samples for laboratory absorbance and fluorescence as well as δ18O–NO3 − isotopes to help interpret the drivers of variable NO3 − and FDOM concentrations measured in situ. In situ data revealed seasonal, event and diurnal patterns associated with hydrological and biogeochemical processes regulating stream NO3 − and FDOM concentrations. An observed decrease in NO3 − concentrations after peak snowmelt runoff and muted response to spring rainfall was consistent with the flushing of a limited supply of NO3 − (mainly from nitrification) from source areas in surficial soils. Stream FDOM concentrations were coupled with flow throughout the study period, suggesting a strong hydrologic control on DOM concentrations in the stream. However, higher FDOM concentrations per unit streamflow after snowmelt likely reflected a greater hydraulic connectivity of the stream to leachable DOM sources in upland soils. We also observed diurnal NO3 − variability of 1–2 μmol l−1 after snowpack ablation, presumably due to in-stream uptake prior to leafout. A comparison of NO3 − and dissolved organic carbon yields (DOC, measured by FDOM proxy) calculated from weekly discrete samples and in situ data sub-sampled daily resulted in small to moderate differences over the entire study period (−4 to 1% for NO3 − and −3 to −14% for DOC), but resulted in much larger differences for daily yields (−66 to +27% for NO3 − and −88 to +47% for DOC, respectively). Despite challenges inherent in in situ sensor deployments in harsh seasonal conditions, these data provide important insights into processes controlling NO3 − and FDOM in streams, and will be critical for evaluating the effects of climate change on snowmelt delivery to downstream ecosystems

The IIASA TPA/70 - X.25 Gateway Network Promotes International Flow of Scientific Information

This paper describes the "TPA/70-X.25 gateway-network" of the International Institute for Applied Systems Analysis (IIASA)in Austria, and of the Institute for Computerization and Automation of the Hungarian Academy of Sciences (SZTAKI) in Hungary, and its promoting role in the on-line exchange of scientific information among national and international institutes and organizations. It presents a short overview of the major categories of transborder data flows relevant to IIASA's work, and how the gate way-network handles them. Finally, some operational and technical aspects of this East-West network of gateways are discussed