Considerable attention has recently been devoted to the linear trend of drought at the decadal to inter-decadal time scale; however, the nonlinear variation of drought at multi-decadal scales and its relation to atmospheric circulation need to be further studied. The linear and nonlinear variations of the Palmer drought severity index (PDSI) in Shandong from 1900 to 2012 and its relations to th...

PROC SQL is SAS’ implementation of the ANSI Standard Query Language (SQL), an ANSI standard database programming/query language. Syntax is simple and its utility is broad in scope. As another capability, we find that PROC SQL is a very useful tool to perform exact test for monotonic trend in mean responses of discrete random variables. In this paper, we show utilization of PROC SQL to construct...

BACKGROUND The association between crystalline silica exposure and risk of heart disease mortality remains less clear. METHODS We investigated a cohort of 42,572 Chinese workers who were potentially exposed to crystalline silica and followed from 1960 to 2003. Cumulative silica exposure was estimated by linking a job-exposure matrix to each person's work history. Low-level silica exposure was...

There seems to be a roughly linear increase of the temperature from about 1800, or even much earlier, to the present. This warming trend is likely to be a natural change; a rapid increase of CO2 began in about 1940. This trend should be subtracted from the temperature data during the last 100 years. Thus, there is a possibility that only a fraction of the present warming trend may be attributed...

The dynamics and the structure of agricultural activities can be examined on the base of the matrix of growth. In this paper, the consumption of different kinds of meat in Central Serbia, during the period from 2000. to 2011, is analyzed using the matrix of growth and curvilinear trend. First, the growth of consumption of the i-th kind of meat was being observed as linear function, using averag...

We forecast high resolution solar irradiance time series using an exponential smoothing state space (ESSS) model. To stationarize the irradiance data before applying linear time series models, we propose a novel Fourier trend model and compare the performance with other popular trend models using residual analysis and the Kwiatkowski-Phillips-Schmidt-Shin (KPSS) stationarity test. Using the opt...

Background and Aim: The process of identifying Covid 19 cases over time (the trend) can provide valuable information about the coverage of diagnostic and screening programs over time. This study aimed to investigate the outpatient trend of Covid-19 in selected comprehensive health service centers of Tehran University of Meical Sciences, Tehran, Iran. Materials and Methods: This was a descripti...

Groundwater, a special hydrological variable and freshwater resource is completely inter-reliant with hydro-metorological, topographic, land use and hydro-geological components of hydrologic cycle. Trend of hydrologic componentsfor future prediction is attempted to confer in this study using Man-Kendall test, linear regression and geometric progression analysis on recorded data collected from r...