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A suite of sinuous ridges with branching and braided morphologies forms an anastomosing network in southern Argyre Planitia, Mars. Several modes of origin have been proposed for the Argyre ridges. Imagery from the High Resolution ...
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A suite of sinuous ridges with branching and braided morphologies forms an anastomosing network in southern Argyre Planitia, Mars. Several modes of origin have been proposed for the Argyre ridges. Imagery from the High Resolution Imaging Science Experiment (HiRISE) and Context Camera (CTX) aboard Mars Reconnaissance Orbiter (MRO) and Mars Orbiter Laser Altimeter (MOLA) topographic data sets from Mars Global Surveyor (MGS) are used to constrain processes involved in formation of the Argyre ridges. We find the characteristics of the ridges and associated layered deposits consistent with glaciolluvial-lacustrine processes and conclude that the ridges are most likely eskers. In particular, variations in ridge height appear to be related to the surrounding surface slope; ridge height increases with descending slopes and decreases with ascending slopes. This characteristic is observed in terrestrial eskers and is related to suhice flow processes. The nature of some eroding beds in the ridges suggests induration. If the Argyre ridges are indeed eskers, the southern Argyre basin was once covered by the margin of a large, thick, stagnating or retreating ice deposit that extended for hundreds of kilometers or more. During ridge formation, water flowed on top, within, or beneath the ice deposit; the continuity and preservation of the ridges suggests that flow was primarily at the base of the ice. The dimensions (up to hundreds of meters tall and several kilometers wide), aspect ratio, and extent (hundreds of kilometers) of the ridges, as well as preliminary calculations of discharge, suggest that a significant amount of water was available.
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Most of the contemporary automatic fingerprint identification systems (AFIS) are based on a dual strategy of combining the minutiae information with the ridge topography in order to improve the overall matching performance. To ens...
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Most of the contemporary automatic fingerprint identification systems (AFIS) are based on a dual strategy of combining the minutiae information with the ridge topography in order to improve the overall matching performance. To ensure the efficiency and robustness of such an AFIS, it is necessary, therefore, to rectify the abnormalities or aberrations of the underlying ridge topography, in general, and to smoothen the uneven/noisy ridgelines, in particular. The proposed work deals with one such problem besetting fingerprint analysis-the problem of eliminating digitization errors that usually creep in during fingerprint acquisition or during preprocessing. The method mainly involves fitting of B-splines for a set of control points chosen appropriately for each ridgeline in a fingerprint image. These fitted splines, in turn, can be used to reconstruct the concerned fingerprint, which, after the rectification procedure, becomes almost devoid of such digitization error. With a proper "smoothness parameter" that determines the extent to which a ridgeline is smoothed, the structural information of the corrected ridgelines produces improved results on fingerprint matching. Experimental results on several databases have been reported, which clearly demonstrate the strength and elegance of the proposed algorithm.
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Ridge analysis is a technique useful in connection with the fitting of second-order response surfaces. It enables a path of maximum predicted y-circumflex values (maximum on a sphere of radius R) to be specified, and followed out ...
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Ridge analysis is a technique useful in connection with the fitting of second-order response surfaces. It enables a path of maximum predicted y-circumflex values (maximum on a sphere of radius R) to be specified, and followed out from the origin of the experimental region, as R increases. (Alternatively, a minimum y path can be followed out.) This article discusses the addition of a measure of uncertainty to the selected path, thus providing an assessment of the reliability of the ridge analysis as a path progresses. The utility of this method is illustrated by applications to two datasets.
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This study presents an efficient approach for large-scale data training. To deal with the rapid growth of training complexity for big data analysis, a novel mechanism, which utilizes fast kernel ridge regression (Fast KRR) and rid...
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This study presents an efficient approach for large-scale data training. To deal with the rapid growth of training complexity for big data analysis, a novel mechanism, which utilizes fast kernel ridge regression (Fast KRR) and ridge support vector machines (Ridge SVMs), is proposed in this study. Firstly, Fast KRR based on low-order intrinsic-space computation is developed. Preliminary support vectors are located by using Fast KRR. Subsequently, the system iteratively removes indiscriminant data until a Ridge SVM with a high-order kernel can accommodate the data size and generate a hyperplane. To speed up the removal of indiscriminant data, quick intrinsic-matrix rebuilding is devised in the iteration. Experiments on three databases were carried out for evaluating the proposed method. Moreover, different percentages of data removal were examined in the test. The results show that the performance is enhanced by as high as 78-152 folds. Besides, the mechanisms still maintain the accuracy. These findings thereby demonstrate the effectiveness of the proposed idea.
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In the early 1990s, several experiments on ridge cultivation of sugarbeet were conducted in Southern Germany, but lack of economic benefits resulted in cessation of activities. In the late 1990s, farmers of tidal marsh areas close...
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In the early 1990s, several experiments on ridge cultivation of sugarbeet were conducted in Southern Germany, but lack of economic benefits resulted in cessation of activities. In the late 1990s, farmers of tidal marsh areas close to the North Sea successfully adapted a ridge cultivation technique derived from carrot growing to sugarbeet crops. From 2004 to 2006, approximately 100 large-scale on-farm trials were run to investigate the effect of ridge cultivation compared to the regional standard of tillage on sugarbeet yield in three beet growing areas of Northern and Western Germany. Recent ridge cultivation techniques are characterized by approximately 15 cm high, reconsolidated ridges. A variety of machine types is used, which have in common driven press rollers for ridge forming combined with a slightly modified commercial drill. At early and moderate sowing dates, ridge soil usually dried earlier and, thus, warmed up faster than conventionally tilled soil. Drying out of ridges could enhance the risk of poor field emergence. Ridge tillage was reported to accelerate and enhance early N supply to plants and, moreover, to cause more uniform and longer beet roots. In the regions of Uelzen/Holstein and East Westphalia, ridge cultivation increased beet yield by 5-10% (sugar content unaffected), whereas in the Rhineland area average yield did not differ between tillage systems. Economic appraisal of ridge cultivation is strongly affected by saving one or two tillage operations compared to the conventional system. Depending on the type of ridge equipment and the reference system used, tillage costs will increase by EUR20-60/ha. At a beet price of approximately EUR30/t, ridge tillage will be economically feasible where it increases the beet yield by 5-7% at a yield level of approximately 65 t/ha.
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Topographic factors are essential to the spatial distribution of ridge orientation, yet the literature shows limited exploration of the mechanisms underlying the effects of terrain on cultivated-land ridge orientation in a black s...
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Topographic factors are essential to the spatial distribution of ridge orientation, yet the literature shows limited exploration of the mechanisms underlying the effects of terrain on cultivated-land ridge orientation in a black soil region. To better understand this subject, interpretation, statistical analyses and field verification were carried out in Songnen Plain, a typical Mollisol area. The results revealed that inclined-ridge cultivation was the most common farming method in the study area. When the slope gradient of cultivated land was greater than 13°, the influence of slope on ridge orientation was obvious, and the residual ridge angle increased with the increase in slope. There was a strongly significant negative correlation between the residual ridge angle and the azimuth angle, and the proportion curves of all ridge orientations with respect to different slope aspects were axisymmetric with respect to azimuth angles of 0°–180°. The relationship among indices such as slope gradient, slope aspect and ridge orientation could be modeled using a Poly2D function. This study indicates that topographic factors are the dominant factor in ridge-orientation selection, and provides a scientific basis for block-scale cultivated-land protection and utilization in black soil region; however, the scientific configuration of ridge orientation requires further research.
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Mixture Models can be used in experimental situations involving areas related to food science and chemistry. Some problems of a statistical nature can be found, such as effects of multicollinearity that result in uncertainty in th...
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Mixture Models can be used in experimental situations involving areas related to food science and chemistry. Some problems of a statistical nature can be found, such as effects of multicollinearity that result in uncertainty in the optimization of a dependent variable. This study proposes the application of the ridge model adapted for mixture planning considering the Kronecker (K-model) and Scheffe (S-Model) methods applied to response surfaces. The method determined the proportions of hexane, acetone and alcohol proportions that resulted in the maximum response of percentage of extracted pequi (Caryocar brasiliense) pulp oil.
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Yield per vine in ridge gourd was significantly and positively associated with number of fruits per plant and the node number at which first female flower appeared, fruit volume and fruit weight. Path coefficient analysis revealed...
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Yield per vine in ridge gourd was significantly and positively associated with number of fruits per plant and the node number at which first female flower appeared, fruit volume and fruit weight. Path coefficient analysis revealed that number of fruits per vine, node number, at which first female flower appeared and fruit volume were the major yield contributing characters with high direct effects on yield per vine.
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In this article, we combine narrative disclosures in the Management Discussion and Analysis (MD&A) Section of 10-K reports with financial variables to generate explicit firm-level forecasts of 1-year-ahead return on equity (ROE). Testing our forecasts out-of-sample, we find that models enhanced with MD&A disclosures are more accurate than models using quantitative financial variables alone. We also find that text-enhanced models are as good as or better than analyst consensus forecasts for small firms and firms with low analyst following. We provide evidence on the informativeness of the MD&A section across different firm characteristics. We find that firms with large changes in future performance, negative future performance, high investor scrutiny, high distress risk, high positive accruals, and high value relevance of earnings have more informative MD&A disclosures, whereas younger firms and firms facing greater market risk and litigation exposure have less informative MD&As. Our results are robust to alternative empirical choices regarding benchmarks and specifications. Overall, our inferences are consistent with MD&A disclosures positively contributing to firms’ information environments....
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In this article, we combine narrative disclosures in the Management Discussion and Analysis (MD&A) Section of 10-K reports with financial variables to generate explicit firm-level forecasts of 1-year-ahead return on equity (ROE). Testing our forecasts out-of-sample, we find that models enhanced with MD&A disclosures are more accurate than models using quantitative financial variables alone. We also find that text-enhanced models are as good as or better than analyst consensus forecasts for small firms and firms with low analyst following. We provide evidence on the informativeness of the MD&A section across different firm characteristics. We find that firms with large changes in future performance, negative future performance, high investor scrutiny, high distress risk, high positive accruals, and high value relevance of earnings have more informative MD&A disclosures, whereas younger firms and firms facing greater market risk and litigation exposure have less informative MD&As. Our results are robust to alternative empirical choices regarding benchmarks and specifications. Overall, our inferences are consistent with MD&A disclosures positively contributing to firms’ information environments.
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Ridges (resp., valley) are the useful geometric features due to their wide varieties of applications, mainly in image analysis problems such as object detection, image segmentation, scene understanding, etc. Many characterizations...
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Ridges (resp., valley) are the useful geometric features due to their wide varieties of applications, mainly in image analysis problems such as object detection, image segmentation, scene understanding, etc. Many characterizations have contributed to formalize the ridge notion. The signification of each characterization rely however on its actual application. The objective analysis of ridge characterized as thin and complex image structure is thus essentially important, for choosing which parameter's values correspond to the suitable configuration to obtain accurate results and optimal performance. In this article an extensive analysis followed by a supervised and objective comparison of different filtering-based ridge detection techniques is led. Furthermore, the optimal parameter configuration of each filtering techniques aimed for image salient feature analysis tool have been objectively investigated, where each chosen filter's parameters corresponds to the width of the desired ridge or valley. At last, the comparative evaluations and analysis results are reported on both synthetic images, distorted with various types of noises and real images.
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