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Ordinary Kriging (OK) is one of the geostatistical methods, which were used in the variation types of mapping, which related to the soil. Compliment by semi variogram models, OK has become one of the most sought out method for the digital mapping, which applied Geographical Information System (GIS) as a main approach. Four semi variogram models, which are spherical, exponential, circular and gaussian would be applied to determine the best model for the mapping purposes, with Root-Mean-Squared-Error (RMSE) as a performance indicator. The value of the cohesion and clay percentage will be based according to the related depth. Each semi variogram model will be applied to determine the best model for each depth, whether it is cohesion or clay percentage, and producing a map, as a result. This mapping would be an alternative to the geological mapping, whereby it would show the range of the cohesion and clay percentage values rather than soil types.

This paper extends the ordinary kriging prediction method and proposes a trend removal method for observed spatial data represented as LR-fuzzy numbers. To this end, a covariance concept was develo...

Land use/cover changes (LULC) are complicated and regionally diverse. When mining regional patterns, the use of a spatial relationship that is determined without considering the spatial correlation...

En la actualidad la necesidad de obtener un predio urbano para construir una unidad habitacional es imperante. El propósito fue determinar el modelo geoestadístico óptimo para la tasación del precio de lotes urbanos en la ciudad de Puno. La metodología aplicada analizó 145 predios en venta los que se dividieron en cuatro zonas urbanas ubicadas por su rumbo, además se usó análisis estructural de datos para las variables área y precio. Los resultados mostraron el área fue de 90,66 ± 10,63 m2, con respecto a los precios prediales la media fue de 107367,03 ± 18772,30 nuevos soles, la coherencia gráfica del semivariograma para la variable precio es el hole effect con un nivel de confianza de 97,52%.

The study objective is to determine the major factors controlling on acoustic and geomechanical properties of carbonate rocks of Jurassic D5 Member of Dhruma Formation. The study integrates petrophysical, petrographic, and geomechanical analysis to characterize different lithofacies, diagenetic properties, shear and compressional wave velocity, rock strength, dynamic elastic moduli, porosity and permeability of carbonate rocks. A total of sixty samples were collected, petrographic thin sections and Scanning Electron Microscopic images were prepared, small cubes and core plugs were prepared for porosity and permeability measurements as well as wave velocities and point load index tests. Porosity and permeability exhibited moderate to poor correlations. P-wave and S-wave velocities are moderately correlated with porosity. However, they showed better correlation with permeability. Poor to moderate direct correlation between dynamic elastic moduli (Poisson ratio and Young modulus) and porosity were found. The lithofacies with large fracture intensity are related to small P-wave velocity values. Four classes were found based on pore type and diagenetic classifications control on acoustic properties: Class 1 is characterized by moldic and intraparticle pore types with limited microporosity, Class 2 is characterized by intensive micro-fracturing, class 3 is intensively cemented, and Class 4 is characterized by microporosity. Micro-fractures pore type samples show the best wave velocity versus porosity correlation followed by densely cemented microporosity and finally moldic and intraparticle show the weakest correlation. Vertical semi-variograms were measured for P and S-wave velocity as well as porosity. A spherical model was found for P and S-wave velocities with zero nugget values and sill values equal to 3 meters. Hole effect reflecting the control of cyclicity was found. Porosity semi-variogram shows exponential modeling with zero nugget value and sill value equal to three meters. This difference in semivariogram between velocity and porosity supports weak and moderate correlations between them.

As forest therapy is getting more attention than ever, it is important to organize time for activity and location based on spatio-temporal distribution of weather condition in forest. This study aimed to analyze precise spatio-temporal distribution of weather condition by installing long-term weather monitoring device in Yonghyun national natural recreation forest and using acquired weather data in order to support forest recreation and therapy activity. First, we statistically compared 4 models of semi-variogram and the results were all similar. We selected and analyzed the circular model for this study because it was presumed to be the best model for this case. We derived 128 results from the circular model and through semi-variogram, we identified seasonal and temporal distributions of temperature and humidity. Then, we used boxplot, made of partial sill level, to identify significant differences in seasonal and temporal distributions. As a result, in spring and early morning, both temperature and humidity showed equalized result. On the other hand, in summer and early afternoon, both temperature and humidity showed uneven result. In spring and early morning, changes in weather condition are shown little from spatial shifting, it is ideal to perform recreational activities and forest therapy but in summer and early afternoon, it is unadvisable to do so as the changes in weather condition could be harmful unless any other means of preparations are made. This study proposes its significance by analyzing seasonal micro-weather of single recreation forest and presenting seasonal and temporal outcomes.KEYWORDS : Spatio-Temporal Distribution, Semi-Variogram, Recreation Forest, Weather Condition

Migration of Tinuvin P (UV stabiliser) and Irganox 3114 (antioxidant) from high-density polyethylene (HDPE) was studied. HDPE pieces were soaked in either milk (1.5% or 3.5% fat content) or 50% (v/v) ethanol-water mixture - the food simulant for milk as specified in Regulation No. 10/2011/EC. The obtained extracts were analysed by LC-MS/MS. For statistical assessment variography was used. It proved to be a useful tool for making a distinction between the early migration range and the equilibrium, despite the variance of the data. Regulation No. 10/2011/EC specifies 10 days of contact time for milk at 5°C. Our experiments with the food simulant with 24 dm(2) kg(-1) surface/mass ratio showed that both Tinuvin P and Irganox 3114 need less than 1 h to reach equilibrium. Furthermore, 10-day experiments with daily sampling showed that these additives are stable in milk, as well as in the food simulant. The effect of the concentration of the additives in HDPE was studied in the 0.01-5% (m/m) range. For both Tinuvin P and Irganox 3114 and all three extractants the migrated amount became independent of the concentration of the additive in the HDPE approximately at 1% (m/m). For Tinuvin P the food simulant gave a close estimate for the milk samples. However, using the food simulant for modelling the migration of Irganox 3114 into milk gave an overestimation with a factor of minimum 3.5. In the case of Tinuvin P special care must be taken, since the recommended amount in the HDPE can result in additive concentrations near or even over the specific migration limit (SML). However, Irganox 3114 cannot reach the SML either in milk or in the food simulant.

Conventional methods of ore deposit estimates are time consuming, whereas geostatistical methods provide quick and reliable estimates with minimum variance. Geostatistical tools, semi-variograms and kriging, have been used for estimation of grades of an iron ore deposit in the present study. In order to model the deposit and estimate grade, 4537 samples collected from 93 boreholes were used in the study. 3-D data have been converted to 2-D for analyzing the variation of Fe within the boreholes. For each borehole, the weighted mean of Fe grade and its coefficient of variation (CV) are calculated and further analysis is carried out for these two variables. Semi-variogram model suggests that the deposit extends over a zone of influence up to 700 m. Grade maps of kriged estimates reveal that the iron ore deposit is distributed in three distinct zones.

Method for reducing the number of wild animal monitors is proposed by means of Kriging. Through wild animal route of simulations with 128 by 128 cells, the required number of wild animal monitors is clarified. Then it is found that the number of wild animal monitors can be reduced based on Kriging by using variograms and semi-variograms among the neighboring monitors. Also, it is found that the number of wild animal monitors by the factor of a by means of the proposed method.

Platinum has been one of the highly needed mineral resources in China. The geochemical exploration at two survey scales was applied in telescoping ore targets for the first time in Eastern Yunnan Pt geochemical province that was delineated using Pt data from flood plain sediments with extra-low sampling density. Our study was based on the delineations and assessments of both regional and local Pt anomalies using the Pt data by analyzing with C-OES the composite samples with two sampling densities. The composite samples were obtained by recomposing at two sampling densities the original stream sediment samples collected by the National Geochemical Mapping Project. Semi-variograms were used to quantitatively describe the variability of Pt anomalies and further analyze the factors controlling the variability. Pt resource potentials of both the regional Pt anomalies and the local Pt anomalies in the study area were estimated based on the geochemical block methods, respectively. It comes to the conclusions as follows. (1) From the regional to local Pt anomaly, the factors controlling their variability from the deep seated faults-basalts turn into the basalts-branch faults, which suggest that Semi-variograms could identify the geological factors controlling the variability of the Pt anomalies identified by the Pt data from the stream sediments with different sampling densities. (2) There exist two types of Pt anomalies in the study area. One is those displaying at sampling densities, and its average Pt concentration significantly increases with sampling density increasing. The other is getting weaker and/or disappears with sampling density increasing. This shows that TOTGEMS could gradually eliminate non-ore anomalies and keep ore anomalies. (3) The average Pt concentration of the local Pt anomaly blocks delineated using Pt data from stream sediments with sampling density of one composite per 16 km2 is twice as much as that of the regional Pt anomaly blocks delineated using Pt data from stream sediments with sampling density of one composite per 64 km2. The Pt resource amount of the local Pt anomaly blocks is 60% of the regional anomaly blocks, but the area of the former is just 35% of the latter, which suggests that the Pt resource amount is mainly concentrated in its local anomalies, and that TOTGEMS has a good exploration function that efficiently approaches ore targets.

Using a tool of regionalized variable theory, the semi-variogram, to remove large-scale trends, the intraregional spatial variability during 1980 of annual, seasonal, monthly, and extreme-event rainfall is investigated for two contrasting rainfall regimes within the UK. These are hydrological areas within East Anglia and south-west England. Altitude is shown to be the dominant factor influencing rainfall variability on these temporal scales in South-west England for space scales of 2–60 km. In East Anglia altitude is again the dominant factor, but in a much more subtle way, for spatial variability on time-scales of a month or more. This more subtle influence does, however, allow information on storm structure to be obtained for individual rain events, as is illustrated by a case study.

A geostatistical technique based on the theory of regionalized variables offers efficient tools for the design of groundwater level monitoring networks. The existing network of groundwater observation wells in the state of Punjab is randomly scattered which does not depict the correct picture of the water table over large areas. The adequacy of the existing observation wells network in the Upper Bari Doab Canal tract was examined by using universal kriging and specified the optimal locations for possible reduction or addition of observation wells for a given level of accuracy. It was found that the present level of accuracy can be maintained by a 12% reduction in the number of existing observation wells. A considerable improvement in the present level of accuracy was estimated by locating additional observation wells hypothetically in the areas having a high estimation error. For further improvement, a square pattern network at 5 km is proposed, having a maximum estimation error of 2.33 m at the centre of the grid. A sensitivity analysis was conducted to test other alternative networks for their efficiency and economic soundness. Copyright © 2005 John Wiley & Sons, Ltd. La technique geostatistique fondee sur la “theorie de variables regionalisees” sert d'outils efficaces pour la conception du reseau de controle du niveau d'eau souterraine. Le reseau actuel des puits d'observation de l'eau souterraine de l'Etat est reparti de maniere aleatoire qui ne traduit pas une image correcte de la nappe souterraine d'une vaste region. Le rapport etudie le caractere adequat du reseau des puits d'observation du canal de la Haute Bari Doab, en utilisant la methode statistique de “krigeage universel”, et determine pour un niveau de precision donne, les lieux optimaux pour une reduction ou augmentation possible du nombre de puits d'observation. Il est constate que le niveau de precision actuel peut etre maintenu en reduisant de 12% le nombre de puits d'observation existants. Une amelioration considerable est remarquee dans le niveau de precision actuel en localisant hypothetiquement d'autres puits d'observation dans les regions susceptibles de grosse erreur. Pour d'autres ameliorations, il est propose de disposer d'un reseau de format carre a une distance de 5 km, ayant une erreur approximative du 2,33 m au centre de la grille. Il est procede a une analyse de sensitivite pour tester d'autres reseaux alternatifs quant a leur efficience et rentabilte economique. Copyright © 2005 John Wiley & Sons, Ltd.

寒冷地における道路トンネルは, 冬期間の凍上防止のために断熱材を施工する例が多くなっており, 施工性・経済性の観点から, 断熱材の合理的な設計が課題となっている. 断熱材の設計厚はトンネル周辺における冬期の気温 (入力値) や地山の熱定数 (パラメータ) の設定値によりに大きく左右される. しかし, 経済的な理由などにより, その正確な推定は容易ではなく, 信頼性の高い断熱材の設計計算が行えないのが現状である. そこで本論文は, 断熱材設計における入力気温の合理的な設定を目的として, トンネル計画サイトの気温変動の推定をアメダス観測値と確率論を基本とした手法 (Semi-Variogram) により試み, その妥当性を実際に得られている観測値との比較を行うことで検証している.

Forest management planning aims at fulfilling the goals of the forest owner. Scheduling treatments of forest stands, both in time and space, have been well investigated previously. Usually, however, these studies have assumed spatially discrete stands, representing imagined treatment units. Furthermore, the stands have been inventoried using ocular methods with varying and unknown precision. As an alternative to this conventional way of describing the forest, an objective circular plot inventory method was used, in the present investigation, to represent the forest on a 400 ha estate. Kriging was used to estimate spatially continuous forest characteristics from the georeferenced inventory plots. Spatial discontinuity, for example, between young and old forests, was handled by making an initial stratification of the forest into age‐classes. This approach enabled several spatially continuous variables, of interest to forest management planning, to be estimated at all locations. The stratification made it po...

We examined twelve temporal series of phytoplankton abundance in a diverse set of marine and freshwater habitats using semi-variogram analysis coupled with a stochastic discrete-time (daily) Gomper...

The basic tool, and probably one of the most used in geostatistics, the variogram, is used to quantify spatial correlations between observations. In fact, this method has become one of the most important — although not necessary — in any natural resource modelling and planning study. For instance, once a Mathematical function (or functions) has been fitted to the experimental variogram, this model can be used to estimate values at unsampled points, by an estimation procedure called kriging (Krige, Matheron, 1970’s), which has been found to be an extract interpolator.

The semi-variogram is widely used in geostatistical data analyses. It is estimatedby the sample semi-variogram. Although some theoretical work has been done on its sampling distribution for a Gaussian process these results are not of immediate practical usage because of the problems induced by the presence of spatial inter-correlations. In this paper various simulation studies are reported which give overwhelming evidence that a logarithmic transformation of the semi-variogram gives approximate normality for moderately large sample sizes. This result is theoretically expected under certain conditions. A robust estimator of the semi-variogram was also studied using the simulations.