A correlation between pulse diagnosis of human body and health monitoring of structures

The concept of health monitoring is a key aspect of the field of medicine that has been practiced for a long time. A commonly used diagnostic and health monitoring practice is pulse diagnosis, which can be traced back approximately five thousand years in the recorded history of China. With advances in the development of modem technology, the concept of health monitoring of a variety of engineering structures in several applications has begun to attract widespread attention. Of particular interest in this study is the health monitoring of civil structures. It seems natural, and even beneficial, that these two health-monitoring methods, one as applies to the human body and the other to civil structures, should be analyzed and compared. In this paper, the basic concepts and theories of the two monitoring methods are first discussed. Similarities are then summarized and commented upon. It is hoped that this correlation analysis may help provide structural engineers with some insights into the intrinsic concept of using pulse diagnosis in human health monitoring, which may be of some benefit in the development of modem structural health monitoring methods.     

Deglacial to middle Holocene (16,600 to 6000 calendar years BP) climate change in the northeastern United States inferred from multi-proxy stable isotope data, Seneca Lake, New York

Climate change in the northeastern United States has been inferred for the last deglaciation to middle Holocene (∼16,600 to 6000 calendar years ago) using multi-proxy data (total organic matter, total carbonate content, δ¹⁸ O calcite and δ¹³ C calcite) from a 5 m long sediment core from Seneca Lake, New York. Much of the regional postglacial warming occurred during the well-known Bolling and Allerod warm periods (∼14.5 to 13.0 ka), but climate amelioration in the northeastern United States preceded that in Greenland by ∼2000 years. An Oldest Dryas climate event (∼15.1 to 14.7 ka) is recognized in Seneca Lake as is a brief Older Dryas (∼14.1 ka) cold event. This latter cold event correlates with the regional expansion of glacial Lake Iroquois and global meltwater pulse IA. An increase in winter precipitation and a shorter growing season likely characterized the northeastern United States at this time. The Intra-Allerod Cold Period (∼13.2 ka) is also evident supporting an “Amphi-Atlantic Oscillation” at this time. The well-known Younger Dryas cold interval occurred in the northeastern United States between 12.9 and 11.6 ka, consistent with ice core data from Greenland. In the Seneca Lake record, however, the Younger Dryas appears as an asymmetric event characterized by an abrupt, high-amplitude beginning followed by a more gradual recovery. Compared to European records, the Younger Dryas in the northeastern United States was a relatively low-amplitude event. The largest amplitude and longest duration anomaly in the Seneca Lake record occurs after the Younger Dryas, between ∼11.6 and 10.3 ka. This “post-Younger Dryas climate interval” represents the last deglacial climate event prior to the start of the Holocene in the northeastern United States, but has not been recognized in Greenland or Europe. The early to middle Holocene in the northeastern United States was characterized by low-amplitude climate variability. A general warming trend during the Holocene Hypsithermal peaked at ∼9 ka coincident with maximum summer insolation controlled by orbital parameters. Millennial- to century-scale variability is also evident in the Holocene Seneca Lake record, including the well-known 8.2 ka cold event (as well as events at ∼7.1 and 6.6 ka). Hemispherical cooling during the Holocene Neoglacial in the northeastern United States began ∼5.5 ka in response to decreasing summer insolation.     

Characterizing solute transport in undisturbed soil cores using electrical and X‐ray tomographic methods

Solute transport in undisturbed soil is a complex process and detailed information on the transport characteristics is needed to provide fundamental understanding of the processes involved. X‐ray computer tomography (CT) and electrical resistivity tomography (ERT) have been used to gain information on the transport characteristics. Both methods are non‐intrusive and do not disturb the soil, in contrast to other methods. CT provides high resolution information on bulk density and macropores, while ERT provides a three‐dimensional image of the internal resistivity structure. By adding a suitable solute under steady‐state flow, the internal resistivity changes can be interpreted as a change in resident concentrations. In our experiment two cores from different field sites were investigated. The ERT measurements revealed two transport modes (one fast and one slow) in one of the cores and only one mode in the other. This was consistent with the results of transfer function modelling on the independently measured breakthrough curves (BTCs). The fast transport mode is perhaps a result of many connected macropores, detected by CT, but this could not be verified with the ERT measurements because of the coarser resolution. However, with ERT in both cases we were able to explain the observed BTC qualitatively. Copyright © 1999 John Wiley & Sons, Ltd.     

Early Ship Observational Data and Icoads

Many surface marine meteorological observations (∼125 million) from ships' logbooks have been assembled in the International Comprehensive Ocean-Atmosphere Data Set (ICOADS) back to the late 18th century. We describe the makeup of the available data before 1950, and a recent update for that period incorporating a variety of US and international sources – focusing on the background, digitization, and processing of the US Maury Collection, which provides the earliest data (mainly 1830–1860) currently blended into ICOADS. We also describe planned data and metadata additions to early ICOADS. Among these, the new Climatological Database for the World's Oceans (CLIWOC) will extend and enhance coverage for 1750–1854. Prospects for data improvements and homogeneity enhancements to further benefit climate research are also discussed.     

Forecasting search areas using ensemble ocean circulation modeling

We investigate trajectory forecasting as an application of ocean circulation ensemble modeling. The ensemble simulations are performed weekly, starting with assimilation of data for various variables from multiple sensors on a range of observational platforms. The ensemble is constructed from 100 members, and member no. 1 is designed as a standard (deterministic) simulation, providing us with a benchmark for the study. We demonstrate the value of the ensemble approach by validating simulated trajectories using data from ocean surface drifting buoys. We find that the ensemble average trajectories are generally closer to the observed trajectories than the corresponding results from a deterministic forecast. We also investigate an alternative model in which velocity perturbations are added to the deterministic results and ensemble mean results, by a first-order stochastic process. The parameters of the stochastic model are tuned to match the dispersion of the ensemble approach. Search areas from the stochastic model give a higher hit ratio of the observations than the results based on the ensemble. However, we find that this is a consequence of a positive skew of the area distribution of the convex hulls of the ensemble trajectory end points.     

Throughfall and stemflow vary seasonally in different land‐use types in a lower montane tropical region of Panama

Catchment hydrology is influenced by land‐use change through alteration of rainfall partitioning processes. We compared rainfall partitioning (throughfall, stemflow and interception) and soil water content in three land‐use types (primary forest, secondary forest and agriculture) in the Santa Fe region of Panama. Seasonal patterns were typified by larger volumes of throughfall and stemflow in the wet season, and the size of precipitation events was the main driver of variation in rainfall redistribution. Land‐use‐related differences in rainfall partitioning were difficult to identify due to the high variability of throughfall. However, annual throughfall in agricultural sites made up a larger proportion of gross precipitation than throughfall in forest sites (94 ± 1, 83 ± 6 and 81 ± 1% for agriculture, primary and secondary forests, respectively). Proportional throughfall (% of gross precipitation becoming throughfall) was consistent throughout the year for primary forest, but for secondary forest, it was larger in the dry season than the wet season. Furthermore, proportional stemflow in the dry season was larger in secondary forest than primary forest. Stemflow, measured only in primary and secondary forests, ranged between 0.9 and 3.2% of gross precipitation. Relative soil moisture content in agricultural plots was generally elevated during the first half of the dry season in comparison to primary and secondary forests. Because throughfall is elevated in agricultural plots, we suggest careful management of the spatial distribution and spread of this land‐use type to mitigate potential negative impacts in the form of floods and high erosion rates in the catchment. Copyright © 2013 John Wiley & Sons, Ltd.     

Gravitational Debye-Hückel theory for a Newtonian cosmology

A correlation function approach is used to formulate a gravitational analogue of equilibrium Debye-Hückel theory appropriate for an expanding Newtonian cosmology. By factoring out the overall expansion of the Universe, one obtains a sensible mathematical framework in which a thermodynamic limit appears to exist. Moreover, one finds that, to lowest non-trivial order, the correlational energy actually vanishes.