Process Analysis and Synthesis

Contains reports on two research projects

Printing Without Paper?

More and more information is being read from cathode ray tube (CRT) screens. Despite improvements in many areas -- display technology, readability of character sets, usable amount of information on a frame, software for handling pages -- a glaring fact remains: reading and browsing through information is still more pleasant using a stack of sheets of paper than using a display screen and electronically stored information. Yet, the preparation of hard-copy pages for once-only (or never) reading seems expensive and wasteful. It is the authors' contention that this need not be the case if new concepts, such as printing on demand, and a concept we shall call multi-time paper (M-paper, for short) are used

Limited Effects of Precipitation Manipulation on Soil Respiration and Inorganic N Concentrations Across Soil Drainage Classes in Northern Minnesota Aspen Forests

It is critical to gain insight into the responses of forest soils to the changing climate. We simulated future climate conditions with growing season throughfall reduction (by 50%) and winter snow removal using a paired-plot design across a soil drainage class gradient at three upland, Populus-dominated forests in northern Minnesota, USA. In situ bulk soil respiration and concentrations of extractable soil N were measured during the summers of 2020–2021. Soil respiration and N concentrations were not affected by throughfall reduction and snow removal, which was largely attributed to the limited treatment effects on soil moisture content and soil temperature. Drainage class was only a significant factor during the spring thaw period in 2021. During this period, the poorly drained plots had lower respiration rates compared to the well-drained plots, which was associated with the drainage class effects on soil temperature. The results of the companion laboratory incubation with varying levels of soil moisture also indicated no effect of the treatment on soil respiration, but effects of drainage class and moisture content on respiration were observed. Our results indicate that the combined effects of reduced summer and winter precipitation on soil respiration and N dynamics may be limited across the range of conditions that occurred in our study

Nonlinear Circuits

Contains reports on four research projects

Trends in stream nitrogen concentrations for forested reference catchments across the USA

To examine whether stream nitrogen concentrations in forested reference catchments have changed over time and if patterns were consistent across the USA, we synthesized up to 44 yr of data collected from 22 catchments at seven USDA Forest Service Experimental Forests. Trends in stream nitrogen presented high spatial variability both among catchments at a site and among sites across the USA. We found both increasing and decreasing trends in monthly flow-weighted stream nitrate and ammonium concentrations. At a subset of the catchments, we found that the length and period of analysis influenced whether trends were positive, negative or non-significant. Trends also differed among neighboring catchments within several Experimental Forests, suggesting the importance of catchment-specific factors in determining nutrient exports. Over the longest time periods, trends were more consistent among catchments within sites, although there are fewer long-term records for analysis. These findings highlight the critical value of long-term, uninterrupted stream chemistry monitoring at a network of sites across the USA to elucidate patterns of change in nutrient concentrations at minimally disturbed forested sites

Interference Problem between ZigBee and WiFi, IPCSIT Vol

Abstract Based on the Internet of Things new services our lives of everyday changed a lot over the past few years. Smart cities, smart homes, e-health are not only exist in our imagination, but they are a reality now. These new solutions are using hundreds or thousands of sensor devices which are collecting data. This huge amount of data needs to be stored for future processing and usage by intelligent IoT services. In the paper we give an overview and profound comparison of the most popular short range communication technologies (e.g. NFC, ZigBee, BT LE, 6LowPAN, RPL, CoAP, IEEE 1902.1, etc.) applied for IoT services and we identify the constraint aspects of the real time Machine to Machine (M2M) communication based on the Internet technologies existing currently