83,188 research outputs found

    Fast approximation of visibility dominance using topographic features as targets and the associated uncertainty

    Get PDF
    An approach to reduce visibility index computation time andmeasure the associated uncertainty in terrain visibility analysesis presented. It is demonstrated that the visibility indexcomputation time in mountainous terrain can be reduced substantially,without any significant information loss, if the lineof sight from each observer on the terrain is drawn only to thefundamental topographic features, i.e., peaks, pits, passes,ridges, and channels. However, the selected sampling of targetsresults in an underestimation of the visibility index ofeach observer. Two simple methods based on iterative comparisonsbetween the real visibility indices and the estimatedvisibility indices have been proposed for a preliminary assessmentof this uncertainty. The method has been demonstratedfor gridded digital elevation models

    Use of GIS for planning visual surveillance installations

    Get PDF
    11-14 September, 2005, Denver, CO, USA. Visual Surveillance is now commonplace in modern societies. Generally, the layout of observers in artificial visual surveillance (e.g., CCTV camera) involves an iterative, manual and gut-feel process of trying various layouts until a satisfactory solution has been found. This paper proposes how a GIS, can be used to identify the optimal number and locations of observers, ensuring complete visual coverage using an automated technique, namely Rank and Overlap Elimination (ROPE). The ROPE technique is a greedy-search method, which iteratively selects the most visibly dominant observer with minimum overlapping vistas. The paper also proposes measurements to characterise the shape of open spaces, relevant in assessing natural surveillance. The paper demonstrates an extension, called Isovist Analyst, to the popular ArcView for planning artificial and natural surveillance in indoor and outdoor open spaces, with arbitrary geometry and topology

    Study of a family of higher order nonlocal degenerate parabolic equations: from the porous medium equation to the thin film equation

    Full text link
    In this paper, we study a nonlocal degenerate parabolic equation of order {\alpha} + 2 for 0<{\alpha}<2. The equation is a generalization of the one arising in the modeling of hydraulic fractures studied by Imbert and Mellet in 2011. Using the same approach, we prove the existence of solutions for this equation for 0<{\alpha}<2 and for nonnegative initial data satisfying appropriate assumptions. The main difference is the compactness results due to different Sobolev embeddings. Furthermore, for {\alpha} > 1, we construct a nonnegative solution for nonnegative initial data under weaker assumptions.Comment: arXiv admin note: text overlap with arXiv:1001.5105 by other author

    Use of plan curvature variations for the identification of ridges and channels on DEM

    Get PDF
    This paper proposes novel improvements in the traditional algorithms for the identification of ridge and channel (also called ravines) topographic features on raster digital elevation models (DEMs). The overall methodology consists of two main steps: (1) smoothing the DEM by applying a mean filter, and (2) detection of ridge and channel features as cells with positive and negative plan curvature respectively, along with a decline and incline in plan curvature away from the cell in direction orthogonal to the feature axis respectively. The paper demonstrates a simple approach to visualize the multi-scale structure of terrains and utilize it for semi-automated topographic feature identification. Despite its simplicity, the revised algorithm produced markedly superior outputs than a comparatively sophisticated feature extraction algorithm based on conic-section analysis of terrain

    \u3ci\u3eChevron\u3c/i\u3e Without the Courts? The Supreme Court\u27s Recent \u3cem\u3eChevron\u3c/em\u3e Jurisprudence Through an Immigration Lens

    Get PDF
    The limits of administrative law are undergoing a seismic shift in the immigration arena. Chevron divides interpretive and decision-making authority between the federal courts and agencies in each of two steps. The Supreme Court may now be transforming this division in largely unrecognized ways. These shifts, currently playing out in the immigration context, may threaten to reshape deference jurisprudence by handing more power to the immigration agency just when the agency may be least able to handle that power effectively. An unprecedented surge in immigration cases—now approximately 90% of the federal administrative docket—has arrived just as the Court is whittling away the judicial role while expanding agency authority, significantly transforming traditional deference doctrine. In its immigration docket, the Court is shifting the judicial role away from questions of statutory interpretation and towards a mere evaluation of when the agency’s interpretation should be granted deference. Assessment of the “reasonableness” of the agency’s action has given way to marking the outer boundaries of agency action, merging the court’s traditional oversight analysis into a form of “arbitrary and capriciousness” review. The costs of the Court’s reformulation of Chevron are particularly visible in immigration law because recent legislation and structural changes at the immigration agency have already constrained judicial review. However, the reformulation of Chevron occurring in immigration law may threaten to remake administrative law generally. Unfortunately, these developments have received little scholarly attention. Understanding this transformation is imperative as ultimately we may be heading towards “Chevron without the Courts”—wherein the judicial interpretive role is being constrained in the very instances where agencies are least able to function effectively

    The Enforceability Of Awards Set Aside At The Seat: An Asian And European Perspective

    Get PDF

    PENGEMBANGAN MEDIA KOMACA (Kotak Mari Membaca) PADA KEGIATAN MEMBACA PERMULAAN DENGAN METODE EJA PADA SISWA KELAS 1 SEKOLAH DASAR

    Get PDF
    Based on observations and interviews with class teachers on October 11 2023, the results of an analysis of the needs of class I students at SD Negeri Mojorejo 01 Batu, showed that the school still uses learning media in the form of textbooks, videos and others, thus concrete learning media is needed. as a support for learning, especially for beginning reading. This aims to increase student interest. The aim of this research is to develop KOMACA learning media using the ADDIE model which has 5 stages, namely analysis, design, development, implementation and evaluation. The data analysis techniques used were qualitative data analysis and quantitative data analysis with the aim of finding out how to develop KOMACA learning media to improve students' reading skills. The development of KOMACA learning media obtained material validation results of 84% and media validation results of 88%. Both validations are categorized as very valid for implementation. Meanwhile, the student response questionnaire received a score of 94% and the results of the teacher response questionnaire were 93%. From both questionnaires, the responses were in the very good category. This can be interpreted as meaning that the development of KOMACA learning media can attract students' attention and interest and make them more active in the learning proces
    corecore