Time Series Analysis

We provide a concise overview of time series analysis in the time and frequency domains, with lots of references for further reading.time series analysis, time domain, frequency domain, Research Methods/ Statistical Methods,

ESTIMATING SITE-SPECIFIC NITROGEN CROP RESPONSE FUNCTIONS: A CONCEPTUAL FRAMEWORK AND GEOSTATISTICAL MODEL

Confirming the precision agriculture hypothesis for variable rate nitrogen applications (VRA) is challenging. To confront this challenge, researchers have used increasingly sophisticated statistical models to estimate and compare site-specific crop response functions (SSCRFs). While progress has been made, it has been hampered by the lack of a conceptual framework to guide the development of appropriate statistical models. This paper provides such a framework and demonstrates its utility by developing a heteroscedastic, fixed and random effects, geostatistical model to test if VRA can increase nitrogen returns. The novelty of the model is the inclusion of site, spatial, treatment, and treatment strip heteroscedasticity and correlation. Applied to data collected in 1995 from two corn nitrogen response experiments in South Central Minnesota, results demonstrate the importance of including site, spatial, treatment, and treatment strip effects in the estimation of SSCRFs. Results also indicate a significant potential for VRA to increase nitrogen returns and that these potential returns increase as the area of the management unit decreases. At one location, there was greater than a 95% chance that VRA could have increased profitability if the cost of implementing VRA was less than 14.5 $ha-1. At the other location, if implementation costs were less than 48.3$ ha-1, there was greater than a 95% chance of increased profitability.Crop Production/Industries,

A Child’s Innocence in Healthcare

A child’s innocence can be deceiving. Their beauty, laughter, and carefree nature can easily blind anyone from seeing and understanding a childs true reality. On my first pediatrics rotation as a third year medical student, I met a little girl with Ebstein’s Anomaly, a rare and serious heart condition. A condition that can present with bluish discoloration to the lips and skin due to lack of oxygen. When this little girl first walked into the examination room, her smile lit up the room and her laughter instantly made me forget why she was even there. After getting lost in her laughter for a few minutes, I started to notice how blue she was. Her hands were blue, her lips were blue. She was a beautiful blue little girl with a big smile that almost made me forget that she just had open heart surgery 3 weeks prior. It was this experience that taught me to admire a childs innoncence , but to not be blinded and underestimate the physical and mental struggles that children live with

Alfred D. Chandlers Konzept der learning base und seine Anwendung auf den Unterhaltungselektronikhersteller Loewe

The aim pursued in this business history study is to assess whether LOEWE - an originally German-Jewish producer of consumer electronics - had the possibility as well as the capacity to build and preserve a learning base throughout the national-socialist period. Learning base is understood here in the sense expounded by the American business historian, Alfred D. Chandler, in his investigation of firms who boast long-term prosperity. After a discussion of this concept, it is applied to LOEWE for the period running from 1923 to 1945. The main thrust of this paper is a focus on the construction of the organisational substructure that supports the learning base in the 1920s. The erosion of the technical knowledge base is then monitored in the field of television research - a domain which will prove central for the firm in the future - as a consequence of the political persecution brought about by the Third Reich

Heavy Hyperon--Antihyperon Production

Based on the experience from the production of anti-Lambda Lambda and anti-Sigma Sigma pairs at LEAR (experiment PS185) it is suggested to continue the investigations towards the heavier antihyperon--hyperon pairs anti-Xi Xi and anti-Omega Omega in view of: (1) the production dynamics of the heavier antihyperon--hyperon out of the anti-p p annihilation (2) a comparison of the (3s 3anti-s quark system) anti-Omega Omega to the (3 (anti-s s)) 3 phi meson production, where both systems have similar masses (3.345 and 3.057, respectively) and identical valence quark content. A systematic study of the antihyperon--hyperon production with increasing strangeness content is interesting for the following reasons: The anti-Omega Omega production is the creation of two spin 3/2 objects out of the two spin 1/2 anti-p p particles. Results of the PS185 experiments prove a clear dominance of the spin triplet anti-s s dissociation. In the Omega anti-Omega the three s-quarks (three anti-s quarks) are aligned to spin 3/2 each. If the three anti-s s pairs are now all in spin triplet configurations when created out of the gluonic interaction they should have spin parity quantum number as 3^- as long as Omega anti-Omega is created with relative L=0 angular momentum. The comparison of the Omega anti-Omega baryon pair to the phi phi phi three meson production (where the three anti-s s quark pairs might not but can be produced without relative correlation) would provide a unique determination of the intermediate matter state. Measurements of excitation functions and polarization transfers should be used to examine these gluon rich anti-p p --> anti-Omega Omega and anti-p p --> phi phi phi reaction channels. Such experiments should be performed at the PANDA detector at the FAIR facility of the GSI.Comment: 4 pages, 2 figures, Presented at LEAP05: International Conference on Low Energy Antiproton Physics, Bonn - Juelich, Germany, May 16-22, 200

THE VALUE OF INFORMATION FOR VARIABLE RATE NITROGEN APPLICATIONS: A COMPARISON OF SOIL TEST, TOPOGRAPHICAL, AND REMOTE SENSING INFORMATION

We explore the value of soil test, topographical, and remote sensing information for guiding variable rate fertilizer applications in corn. Results suggest combining topographical and remote sensing information is more valuable than conventional soil tests. Considered separately, topographical and remote sensing information is not always as valuable as soil tests.Crop Production/Industries,

Analytic approximations to the phase diagram of the Jaynes-Cummings-Hubbard model with application to ion chains

We discuss analytic approximations to the ground state phase diagram of the homogeneous Jaynes-Cummings-Hubbard (JCH) Hamiltonian with general short-range hopping. The JCH model describes e.g. radial phonon excitations of a linear chain of ions coupled to an external laser field tuned to the red motional sideband with Coulomb mediated hopping or an array of high-$Q$ coupled cavities containing a two-level atom and photons. Specifically we consider the cases of a linear array of coupled cavities and a linear ion chain. We derive approximate analytic expressions for the boundaries between Mott-insulating and superfluid phases and give explicit expressions for the critical value of the hopping amplitude within the different approximation schemes. In the case of an array of cavities, which is represented by the standard JCH model we compare both approximations to numerical data from density-matrix renormalization group (DMRG) calculations.Comment: 9 pages, 5 figures, extended and corrected second versio

Mesoscale movement and recursion behaviors of Namibian black rhinos.

Background:Understanding rhino movement behavior, especially their recursive movements, holds significant promise for enhancing rhino conservation efforts, and protecting their habitats and the biodiversity they support. Here we investigate the daily, biweekly, and seasonal recursion behavior of rhinos, to aid conservation applications and increase our foundational knowledge about these important ecosystem engineers. Methods:Using relocation data from 59 rhinos across northern Namibia and 8 years of sampling efforts, we investigated patterns in 24-h displacement at dawn, dusk, midday, and midnight to examine movement behaviors at an intermediate scale and across daily behavioral modes of foraging and resting. To understand recursion patterns across animals' short and long-term ranges, we built T-LoCoH time use grids to estimate recursive movement by each individual. Comparing these grids to contemporaneous MODIS imagery, we investigated productivity's influence on short-term space use and recursion. Finally, we investigated patterns of recursion within a year's home range, measuring the time to return to the most intensively used patches. Results:Twenty four-hour displacements at dawn were frequently smaller than 24-h displacements at dusk or at midday and midnight resting periods. Recursion analyses demonstrated that short-term recursion was most common in areas of median rather than maximum NDVI values. Investigated across a full year, recursion analysis showed rhinos most frequently returned to areas within 8-21 days, though visits were also seen separated by months likely suggesting seasonality in range use. Conclusions:Our results indicate that rhinos may frequently stay within the same area of their home ranges for days at a time, and possibly return to the same general area days in a row especially during morning foraging bouts. Recursion across larger time scales is also evident, and likely a contributing mechanism for maintaining open landscapes and browsing lawns of the savanna