scholarly journals Approximate Shortest Distance Computing: A Query-Dependent Local Landmark Scheme

2012 ◽  
Author(s):  
Miao Qiao ◽  
Hong Cheng ◽  
Lijun Chang ◽  
Jeffrey Xu Yu
Keyword(s):  
Shortest Distance ◽  
Local Landmark

scholarly journals Approximate Shortest Distance Computing: A Query-Dependent Local Landmark Scheme

2014 ◽  
Vol 26 (1) ◽  
pp. 55-68 ◽  
Author(s):  
Miao Qiao ◽  
Hong Cheng ◽  
Lijun Chang ◽  
Jeffrey Xu Yu
Keyword(s):  
Shortest Distance ◽  
Local Landmark

Path Planning of Mobile Robot Using Improved Artificial Bee Colony Algorithm

2020 ◽  
Vol 38 (9A) ◽  
pp. 1384-1395
Author(s):  
Rakaa T. Kamil ◽  
Mohamed J. Mohamed ◽  
Bashra K. Oleiwi
Keyword(s):  
Mobile Robot ◽  
Comparative Research ◽  
Artificial Bee Colony Algorithm ◽  
Artificial Bee Colony ◽  
Dynamic Control ◽  
Computational Time ◽  
Bee Colony ◽  
Shortest Distance ◽  
Minimum Number ◽  
Cubic Polynomial

A modified version of the artificial Bee Colony Algorithm (ABC) was suggested namely Adaptive Dimension Limit- Artificial Bee Colony Algorithm (ADL-ABC). To determine the optimum global path for mobile robot that satisfies the chosen criteria for shortest distance and collision–free with circular shaped static obstacles on robot environment. The cubic polynomial connects the start point to the end point through three via points used, so the generated paths are smooth and achievable by the robot. Two case studies (or scenarios) are presented in this task and comparative research (or study) is adopted between two algorithm’s results in order to evaluate the performance of the suggested algorithm. The results of the simulation showed that modified parameter (dynamic control limit) is avoiding static number of limit which excludes unnecessary Iteration, so it can find solution with minimum number of iterations and less computational time. From tables of result if there is an equal distance along the path such as in case A (14.490, 14.459) unit, there will be a reduction in time approximately to halve at percentage 5%.

scholarly journals Initial Clinical Experience With a New Conformable Abdominal Aortic Endograft: Aortic Neck Coverage and Curvature Analysis in Challenging Aortic Necks

2021 ◽  
pp. 152660282199672
Author(s):  
Alice Finotello ◽  
Richte Schuurmann ◽  
Sara Di Gregorio ◽  
Gian Antonio Boschetti ◽  
Nabil Chakfé ◽  
...  
Keyword(s):  
Aortic Wall ◽  
Surface Coverage ◽  
Infrarenal Aorta ◽  
Technical Success ◽  
Curvature Analysis ◽  
Average Curvature ◽  
Aortic Neck ◽  
Abdominal Aortic ◽  
Shortest Distance ◽  
New Generation

Objectives: Aim of this work was to investigate precision of deployment and conformability of a new generation GORE EXCLUDER Conformable Endoprosthesis with active control system (CEXC Device, W.L. Gore and Associates, Flagstaff, AZ, USA) by analyzing aortic neck coverage and curvature. Methods: All consecutive elective patients affected by abdominal aortic aneurysm or aortoiliac aneurysm treated at our institution between November 2018 and June 2019 with the new CEXC Device were enrolled. Validated software was adopted to determine the available apposition surface area into the aortic neck, apposition of the endograft to the aortic wall, shortest apposition length (SAL), shortest distance between the endograft fabric and the lowest renal arteries (SFD) and between the endograft fabric and the contralateral renal artery (CFD). Pointwise centerline curvature was also computed. Results: Twelve patients (10 men, median age 78 years (71.75, 81.0)) with available pre- and postoperative computed tomography angiography (CTA) were included. Technical success was obtained in all the cases. Preoperative median length of the proximal aortic neck was 16.1 mm (10.7, 21.7) and suprarenal (α) and infrarenal (β) neck angulation were, respectively, 28.9° (15.7°, 47.5°) and 75.0° (66.9°, 81.4°). Postoperative median apposition surface coverage was 79% (69.25%, 90.75%) of the available apposition surface. SFD and CFD were 1.5 mm (0.75, 5.25) and 7 mm (4.5, 21.5), respectively. Average curvature over the infrarenal aorta decreased from 25 m−1 (21.75, 29.0) to 22.5 m−1 (18.75, 24.5) postoperatively (p=0.02). Maximum curvature did not decrease significantly from 64.5 m−1 (54.25, 92.0) to 62 m−1 (41.75, 71.5) (p=0.1). Conclusions: Our early experience showed that deployment of the CEXC Device is safe and effective for patients with challenging proximal aortic necks. Absence of significant changes between pre- and postoperative proximal aortic neck angulations and curvature confirms the high conformability of this endograft.

scholarly journals Shortest Distance Between Multiple Orbits and Generalized Fractal Dimensions

2021 ◽  
Author(s):  
Vanessa Barros ◽  
Jérôme Rousseau
Keyword(s):  
Fractal Dimensions ◽  
Shortest Distance

scholarly journals Uncertainty promotes information-seeking actions, but what information?

2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Ashlynn M. Keller ◽  
Holly A. Taylor ◽  
Tad T. Brunyé
Keyword(s):  
Information Seeking ◽  
Empirical Work ◽  
Information Gathering ◽  
Continuous Data ◽  
Final Choice ◽  
Navigation Data ◽  
Spatial Reorientation ◽  
Local Landmark ◽  
Empirical Approaches ◽  
Cue Conflict

Abstract Navigating an unfamiliar city almost certainly brings out uncertainty about getting from place to place. This uncertainty, in turn, triggers information gathering. While navigational uncertainty is common, little is known about what type of information people seek when they are uncertain. The primary choices for information types with environments include landmarks (distal or local), landmark configurations (relation between two or more landmarks), and a distinct geometry, at least for some environments. Uncertainty could lead individuals to more likely seek one of these information types. Extant research informs both predictions about and empirical work exploring this question. This review covers relevant cognitive literature and then suggests empirical approaches to better understand information-seeking actions triggered by uncertainty. Notably, we propose that examining continuous navigation data can provide important insights into information seeking. Benefits of continuous data will be elaborated through one paradigm, spatial reorientation, which intentionally induces uncertainty through disorientation and cue conflict. While this and other methods have been used previously, data have primarily reflected only the final choice. Continuous behavior during a task can better reveal the cognition-action loop contributing to spatial learning and decision making.

Distance From Projections to Nilpotents

1995 ◽  
Vol 47 (4) ◽  
pp. 841-851 ◽  
Author(s):  
Gordon W. Macdonald
Keyword(s):  
Operator Norm ◽  
Arbitrary Rank ◽  
Shortest Distance ◽  
Nilpotent Operators ◽  
Rank One

AbstractThe distance from an arbitrary rank-one projection to the set of nilpotent operators, in the space of k × k matrices with the usual operator norm, is shown to be sec(π/(k:+2))/2. This gives improved bounds for the distance between the set of all non-zero projections and the set of nilpotents in the space of k × k matrices. Another result of note is that the shortest distance between the set of non-zero projections and the set of nilpotents in the space of k × k matrices is .

The Shortest Distance Between Two Nearly Antipodean Points on the Surface of a Spheroid

1992 ◽  
Vol 45 (1) ◽  
pp. 114-125
Author(s):  
R. Williams ◽  
J. E. Phythian
Keyword(s):  
The Earth ◽  
Shortest Distance

Lambert, in his paper entitled The distance between two widely separated points on the surface of the Earth, published in 1942, having given a solution which was applicable in most cases, stated that there was a particular problem in determining the shortest distance between two nearly antipodean points on the surface of the spheroidal Earth but this was not fully analysed in that paper.

Towards a Multi Objective Path Optimisation for Car Navigation

2011 ◽  
Vol 65 (1) ◽  
pp. 125-144 ◽  
Author(s):  
Ching-Sheng Chiu ◽  
Chris Rizos
Keyword(s):  
Selection Criteria ◽  
Empirical Studies ◽  
Route Selection ◽  
Multi Objective ◽  
Optimal Paths ◽  
Proposed Model ◽  
Shortest Distance ◽  
Shortest Path Algorithms ◽  
Car Navigation System ◽  
Car Navigation

In a car navigation system the conventional information used to guide drivers in selecting their driving routes typically considers only one criterion, usually the Shortest Distance Path (SDP). However, drivers may apply multiple criteria to decide their driving routes. In this paper, possible route selection criteria together with a Multi Objective Path Optimisation (MOPO) model and algorithms for solving the MOPO problem are proposed. Three types of decision criteria were used to present the characteristics of the proposed model. They relate to the cumulative SDP, passed intersections (Least Node Path – LNP) and number of turns (Minimum Turn Path – MTP). A two-step technique which incorporates shortest path algorithms for solving the MOPO problem was tested. To demonstrate the advantage that the MOPO model provides drivers to assist in route selection, several empirical studies were conducted using two real road networks with different roadway types. With the aid of a Geographic Information System (GIS), drivers can easily and quickly obtain the optimal paths of the MOPO problem, despite the fact that these paths are highly complex and difficult to solve manually.

The Model for Icosahedral Al-Pd-Mn phase based on the T*(2F) Canonical Tiling

2000 ◽  
Vol 643 ◽  
Author(s):  
Gerald Kasner ◽  
Zorka Paradopolos
Keyword(s):  
Symmetry Axis ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Fibonacci Sequence ◽  
Shortest Distance ◽  
Atomic Species ◽  
Three Dimensional Space

AbstractThe icosahedral canonical tiling of the three-dimensional space by six golden tetahedra T*(2F) [1] is decorated for physical applications by the Bergman polytopes [2]. The model can be also formulated as the “primitive) tiling TP [3] decorated by alternating Bergman symmetry axis of and icosahedron, there appear the plans on three mutual distances following the rule of a decorated Fibonacci sequence. All these three distances among the terraces (mutually scaled by a factor τ) have been recently observed by shen et al. [5]. In particular they have measured also the shortest distance of 2.52Å that breaks the Fibonnaci-sequence of terrace like surfaces measured previously by schaub et al. [6]. We predict the frequencies for the appearance of the terraces of different heights in the model under the condition that the model of Boudard et al. [7.8], we decorate the atomic positions by Al, Pd and Mn. We present images of the predicted possible terrace-like surfaces on three possible distances in the fully decorated model by the atomic species.

scholarly journals Automated Parking Space Allocation during Transition with both Human-Operated and Autonomous Vehicles

2021 ◽  
Vol 11 (2) ◽  
pp. 855
Author(s):  
Mingkang Wu ◽  
Haobin Jiang ◽  
Chin-An Tan
Keyword(s):  
Autonomous Vehicles ◽  
Transition Period ◽  
Search Algorithm ◽  
Parking Space ◽  
Key Factors ◽  
Comprehensive Method ◽  
Space Allocation ◽  
Shortest Distance ◽  
Parking Lot ◽  
Ranking Order

As fully automated valet parking systems are being developed, there is a transition period during which both human-operated vehicles (HVs) and autonomous vehicles (AVs) are present in the same parking infrastructure. This paper addresses the problem of allocation of a parking space to an AV without conflicting with the parking space chosen by the driver of a HV. A comprehensive assessment of the key factors that affect the preference and choice of a driver for a parking space is established by the fuzzy comprehensive method. The algorithm then generates a ranking order of the available parking spaces to first predict the driver’s choice of parking space and then allocate a space for the AV. The Floyd algorithm of shortest distance is used to determine the route for the AV to reach its parking space. The proposed allocation and search algorithm is applied to the examples of a parking lot with three designed scenarios. It is shown that parking space can be reasonably allocated for AVs.

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