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This paper provides a new idea for interpolating complex curves and surfaces by fractal interpolation. A type of bivariate fractal interpolation functions with function vertical scaling factors for the special interpolation data set is presented. The interpolation algorithm is proposed for complex curves by contour lines of two types of fractal interpolation functions which are proposed by this paper and Navascués et al. [Construction of fractal surfaces, Fractals 28(2) (2020) 2050033], respectively. Meanwhile, some properties of the interpolation algorithm are introduced. Then, the two classes of fractal interpolation functions are extended to the cases of trivariate functions. We also introduce the interpolation algorithm for complex surfaces based on iso-surfaces of fractal interpolation functions constructed. Finally, several examples are provided. [ABSTRACT FROM AUTHOR]

In order to establish the technology system for the tissue culture and rapid propagation of Acacia podalyriifolia, the response surface method (RSM) was used to optimize the adventitious bud induction, proliferation and the rooting medium formula. Based on the previous single factor pre-test, the induction rate, proliferation coefficient and rooting rate were taken as the response values. The response surface methods of Central Composite Design (CCD) and Box-Behnken (BBD) test design were used to optimize the optimal hormone ratio for the adventitious bud induction, proliferation and rooting culture of Acacia podalyriifolia. The results showed that the optimum induction medium was MS+3. 0 mg • L_1 6-BA+0. 35 mg • L_1 IBA+0. 2 mg • L_1 GA3, and the induction rate was 62. 89%. The optimal proliferation medium was 1/2MS+0. 66 mg/L 6-BA+0. 45 mg • L_1 IBA+0. 11 mg • L_1 GA3, and the proliferation coefficient was 3. 78. The optimal rooting medium was 1/2MS+0. 64 mg • L_1 IBA+0. 14 mg • L_1 NAA, and the rooting rate was 79. 91%. At the same time, the actual value was found to be in line with the expectation according to the contour line map and response surface analysis of the interaction between the factors of response surface method. In conclusion, the prediction of the regression equation established by using the response surface method had a good fitting degree with the actual experiment, which could be used to optimize the medium conditions for tissue culture of Acacia podalyriifolia, The transplanting substrate was yellow subsoil + sand (the volume ratio of yellow subsoil and sand was 2: 1), and the transplanting survival rate could reach more than 90%. [ABSTRACT FROM AUTHOR]

This study aims to employ both central processing units (CPUs) and graphics processing units (GPUs) to collaboratively generate contour lines from a large-scale digital elevation model (DEM). The performance was improved with regard to three aspects. First, the original DEM data were decomposed and assigned according to the GPU's limited memory so that large-scale data could be correctly addressed. Second, different types of computational tasks between the CPUs and GPUs were dynamically scheduled to ensure that both accelerators cooperate for performance improvement. Third, parallel processing on GPUs and CPUs was separately optimized for more efficient acceleration. Experimental results indicated that applying the parallel algorithm to data with a volume of 37.81 GB and area of 5,975,625.16 km2 reduced the total execution time from 332.84 min to 8.29 min for an optimal speedup of 40.15. In addition, we investigated the effects of the computational intensity, decomposition granularity, and task scheduling on parallel efficiency and performance improvement. We also discussed its degree of effectiveness, broader application, and the future direction of research in the field of geographic information systems. [ABSTRACT FROM AUTHOR]

Contour lines are a key features of topographic maps as they make the comprehension of terrain more easy. But they are no longer drawn by cartographers, they are mostly automatically derived from digital terrain models. Despite real progress in this automated derivation, some specific terrain landscapes remain incorrectly depicted with such techniques, and this is the case for karstic plateaus full of sinkholes. This paper proposes a specific automated method to derive better contour lines in plateaus, particularly around sinkholes. The process first detects karstic plateaus with many sinkholes, as well as the individual sinkholes. Then, the MNT is smoothed to better reflect the terrain in the plateau and in its surroundings. As a third step, the contour lines around sinkholes are enhanced to draw legible round features that better reflect the real terrain. The process was implemented in a QGIS plugin and tested on a small area with a karstic plateau in the Jura mountain in France, and the cartographers of IGN, the French national mapping agency assessed the results as a great improvement compared to the generic automated process to derive contour lines. [ABSTRACT FROM AUTHOR]

Safe landing site selection of a planetary lander is one of the most important technologies for the lander's mission success. In this paper, a new concept for safe landing site selection is proposed based on the digital terrain map and contour lines generated by light detection and ranging (LIDAR) measurements. The design parameters of the proposed approach are defined and systematically classified. Then, the effect of key parameters related to the performance of the algorithm, i.e., terrain roughness is analyzed by comparing the results of three different types of terrain. The simulation results show that the proposed method is well-performed under various circumstances. [ABSTRACT FROM AUTHOR]

Sloping farmlands are the major sources of soil, water and nutrient losses in arid and semi-arid regions. Information about the impacts of different tillage practices on soil erosion, nutrient loss and crop nutrient uptake on the sloping farmland of semi- arid soil is, however, limited. This study was carried out to investigate the effects of tillage direction on soil, water, nitrogen and phosphorous losses and their uptake by plant in a rainfed wheat land. Field experiments were conducted in two tillage directions: downslope tillage and contour line tillage with four fertilization treatments: control, urea, triple superphosphate, and urea + triple superphosphate at the field plots with 1.75 m 8 m in dimensions by using the randomized completely block design at three replications in Zanjan Township during 2014-2015. According to the results, Significant differences were found between the two tillage practices in soil loss (P < 0.001), water loss (P < 0.001), nitrogen loss soil loss (P < 0.001), and nitrogen uptake by wheat grain (P < 0.001), while phosphorous loss and its uptake did not show any statistically significant difference. Soil and water loss in the downslope tilled plots was 1.65 and 2.50 times higher than the contour line tillage, respectively. Nitrogen loss in the downslope tilled plots was 1.29 times more than that in the contour line tilled plots. Nitrogen loss in the plots was attributed to soil and water loss, so significant relationships were observed between nitrogen loss and soil loss (R2 = 0.59) and water loss (R2 = 0.55). This study, therefore, revealed that the tillage direction is an important factor controlling runoff, soil loss, and nitrogen loss and its uptake by wheat in the rainfed lands of semi-arid regions. Application of the contour tillage is, therefore, the first step to conserve soil and water and to improve soil productivity in these regions. [ABSTRACT FROM AUTHOR]

Abstract Decimal reduction time (D -value) based on the first-order survival kinetics model is not sufficient for reliable estimation of the bacterial survivors of inactivation treatment because the model does not consider inactivation curvature. However, even though doubt exists in the calculation of D -value, it is still widely used for risk assessment and sterilisation time estimation. This paper proposes an approach for estimating the time-to-inactivation and death probability of bacterial population that considers individual cell heterogeneity and initial number of cells via computer simulation. In the proposed approach, Weibull and Poisson distributions are respectively used to provide individual cell inactivation time variability and initial number of cells variability. Our simulation results show that the time-to-inactivation significantly depends on kinetics curvature and initial number of cells. For example, with increases in the initial number of cells, the respective variance of the time-to-inactivation of log-linear, concave downward curve, and concave upward curve remains constant, decreases, and increases, respectively. The death probability contour plot was successfully generated via our computer simulation approach without using D -value estimation. Further, the death probability calculated using our stochastic approach was virtually the same as that obtained using inactivation kinetics. We validated the simulation by using literature data for acid inactivation of Salmonella population. The results of this study indicate that inactivation curvature can replace D -value extrapolation to estimate the death probability of bacterial population. Further, our computer simulation facilitates realistic estimation of the time-to-inactivation of bacterial population. The R code used for the above stochastic calculation is outlined. Highlights • Bacterial time-to-inactivation and death probability estimation approach is proposed • Proposed approach considers individual cell heterogeneity and initial number of cells • Decimal reduction time extrapolation is replaced with stochastics estimation • The variance of the time-to-inactivation depends on kinetics curvature and initial number of cells. [ABSTRACT FROM AUTHOR]

In recent years, the research of marine environmental monitoring system has been especially popular. The construction of Internet of things between devices occupies the main position in marine environment detection system. In order to protect and utilize marine resources, it is urgent to realize the collection and treatment of marine information. We have established the Internet of things system for large ocean data collected by sensors. We calculate the ocean data in terminal devices such as sensors. In the process of calculation and arrangement of data, this paper presents a new method for the calculation of data contours. The aim of this method is to quickly describe the contour of data. The distribution of contour lines can be calculated accurately in a short time. This paper introduces the principle and calculation process of the method. The simulation of big data calculation is carried out in practice. The simulation results are also analyzed. Finally, the advantages of this method are illustrated by comparison simulation. In the same set of data and conditions, the method achieves the improvement of computational efficiency and calculation accuracy. It has certain significance in practical application. [ABSTRACT FROM AUTHOR]

In order to provide fundamental information for exploration and related scientific research on the Moon and other planets, we propose a new automatic method to recognize craters on the lunar surface based on contour data extracted from a digital elevation model (DEM). Through DEM and image processing, this method can be used to reconstruct contour surfaces, extract and combine contour lines, set the characteristic parameters of crater morphology, and establish a crater pattern recognition program. The method has been tested and verified with DEM data from Chang’E-1 (CE-1) and Chang’E-2 (CE-2), showing a strong crater recognition ability with high detection rate, high robustness, and good adaptation to recognize various craters with different diameter and morphology. The method has been used to identify craters with high precision and accuracy on the Moon. The results meet requirements for supporting exploration and related scientific research for the Moon and planets. [ABSTRACT FROM AUTHOR]

Based on the principle of hot stamping, a simulation model of hot stamping is proposed. The blank contour line of U-shaped part is optimized by using a multiple iterative algorithm. By comparison of the simulated and experimental data, the multiple iterative optimization algorithm is verified. Moreover, the blank contour lines of a bumper and the B-pillar of Numisheet 2008 were optimized. The results obtained indicate that the multiple iterative method for optimizing the initial blank contour line has high calculating speed and accuracy. The hot stamping part contour lines match the ideal part contour lines quite well. [ABSTRACT FROM AUTHOR]

The reading, analysis and interpretation of the contour line picture is causing pupils quite a lot of problems. They result above all from lack of abilities of getting the third dimension out of the two-dimensional plain. On the one side different perceptual predisposition of pupils affects such a state of affairs, on the other - insufficient methodological base, mainly in the form of interesting, attractive, inspiring and modern teaching tools. SandBOX seems to be a reply to this demand. SandBOX is a multimedia tool for generating and showing the picture of colorful map-contour line on the freely formed, interactive model of sand. The user immediately is seeing the three-dimensional space created by himself in the form of colorful hypsometric map. This device can easily help understand the process of mapping and reading information about the terrain on the hypsometric map. [ABSTRACT FROM AUTHOR]

Analysis is given to acoustic directional radiation tuned by rotating square rods in two-dimensional (2D) solid-fluid phononic crystals (PC). The contour line method is introduced which predicts how the acoustic waves propagate at different frequency. As a specific example, for the systems of steel rods with square cross-section in a water host, we employ this approach to the analysis of the directivity successfully. The directional radiation frequency of two lowest bands are studied in this paper. The results show that the directional radiation frequency can be turned in a wide range by rotating the square rods. While the directivity of acoustic propagation keeps unchanged when the acoustic directional radiation frequency is located in the same band. Moreover, PCs exhibit excellent characteristic of single radiation branch as a corner cut off in a finite structure. Our approach may supply a new way to tune the directional radiation frequency. [ABSTRACT FROM AUTHOR]

The relief and contour lines on a group of ancient Greek red-figure vases and vase fragments in the collection of the Harvard Art Museums and the Worcester Art Museum were examined using two surface examination methods - reflectance transformation imaging and three-dimensional laser scanning confocal microscopy. These methods helped characterize the lines and answer questions regarding tools, techniques, and production sequence used by Greek vase painters. This research also incorporated fabricated mock-ups to gain a better understanding of the ancient technology and in so doing confirmed that the relief lines were not produced by an extruded method, but with a brush made with only a few hairs, termed linierhaar as first proposed by Gérard Seiterle in 1976. Furthermore, it was discovered that not one but two distinct types of relief lines exist on these ancient vases: the laid line (proposed by Seiterle) which has a characteristic ridged profile, and the pulled line (proposed in a previous publication by the authors) which has a furrowed profile. It was also determined that the relief line used to outline figures was applied prior to the contour line in Attic vase decoration, although variations in this sequence occur in vases from South Italy. Based on observations made during this research, the authors propose a likely evolution for the techniques used to produce decorative features throughout the period of red-figure vase production. [ABSTRACT FROM AUTHOR]

Abstract: This paper introduces a parallel contour line interpolation algorithm from Digital Elevation Model (DEM). Contour generation from DEM is the basic task of the computer-aided mapping and one of the most important applications of DEM. With the increasing of DEM resolution, the Digital Terrain Analysis (DTA) has become one of the computing-intensive tasks in GIS. Many studies have been done on the implementation of parallel DTA algorithms based on different parallel hardware and software. In this paper, we use the open source GIS toolkit to implement a parallel contour generation algorithm. The Message Passing Interface (MPI) standard is used for the parallel algorithm programming. A slackly LAN (Local Area Network)-connected windows cluster is setup to implement and test the parallel contour line generation algorithm. The performance optimization method for the parallel algorithm is specifically discussed, including data redundancy method, group communication, packaging collection of results, and memory optimization method for results merging. The experimental results show the capacity and potential to implement the parallel GIS algorithms based on open source GIS toolkit in the LAN-connected PC environment. [Copyright &y& Elsevier]

Abstract: Catalysts that are made of composite particles may comprise several compounds, where each compound utilizes its own specific properties, thus providing synergistic effects that cannot be found when the constituents are used separately. Developing and quality control of such particles require measuring the shape of the domains and the length of the contact line between domains made from different compounds. In what follows, the feasibility of using Fluorescence Resonance Energy Transfer (FRET) in order to gain information on the length of contour lines between neighboring domains is demonstrated. The principle of the method is to selectively adsorb the donor on one type of domain while selectively adsorbing the acceptor on the second type of domain. The requirement for a short distance between the acceptor dye molecule and the donor dye molecule in order to obtain fluorescence is then translated into a linear dependence between the emission intensity and the contour line length. This facilitates, upon using calibrated standards, the calculation of the average length of the contour between domains. [Copyright &y& Elsevier]

Abstract: Contour lines are an important means of cartographical visualization. If computed automatically on a triangulation, they contain many artefacts. This paper shows the results of their elimination by using constrained edges in the triangulation. Constrained edges can be inserted either manually by an editor – which enables all kinds of detected artefacts to be improved manually – or automatically for some kinds of artefacts only. We present a survey of detected artefacts, evaluation of the Delaunay and greedy triangulations as to the number and kind of contour line artefacts, examples of achievements using manual placement of constrained edges and two algorithms suitable for automatic detection and removal of artefacts caused by flat triangle areas. According to our results, problems are not completely removed but the number of problematic areas is decreased substantially. [Copyright &y& Elsevier]

Abstract: Focusing on conjunctive, left-continuous, increasing functions T we redefine the rotation invariance property in terms of contour lines. Under the assumption of the existence of a neutral element , this rotation invariance property requires some partial commutativity and associativity. The functions that are rotation invariant w.r.t. all of their contour lines are characterized. [Copyright &y& Elsevier]

Given an involutive negator N and a left-continuous t-norm T that either has no zero divisors or is rotation invariant, we build a rotation-invariant t-norm from a rescaled version of T and its left, right and front rotation. Depending on the involutive negator N and the set of zero divisors of T, some reshaping of the rescaled version of T may occur during the rotation process. The rescaled version of T itself can be understood as the -zoom of the newly constructed rotation-invariant t-norm, with the unique fixpoint of N. Starting with a rotation-invariant t-norm T there is, however, one important restriction. The triple rotation method based on the involutive negator N will yield a t-norm if and only if the companion Q of T is commutative on . When Q is not commutative on , there even does not exist a rotation-invariant t-norm with -zoom equal to T. [Copyright &y& Elsevier]

Abstract: Contour lines totally fix the structure of a t-norm. Expressing the characteristic properties of a left-continuous t-norm in terms of contour lines, provides us more insight into its geometrical structure. In particular, we focus on the decomposition of t-norms that have a continuous contour line. [Copyright &y& Elsevier]