Optimal Autonomous Pursuit of an Intruder on a Grid Aided by Local Node and Edge Sensors

2021 ◽  
pp. 1-16
Author(s):  
Sufal Chandra Swar ◽  
Suresh Manickam ◽  
David Casbeer ◽  
Krishna Kalyanam ◽  
Swaroop Darbha
Keyword(s):  
Unmanned Vehicles ◽  
Smart Sensors ◽  
Worst Case ◽  
Detection Systems ◽  
Central Node ◽  
International Borders ◽  
Security Personnel ◽  
Adjacent Node ◽  
Minimum Number ◽  
Unit Speed

Timely detection of intruders ensures the safety and security of high valued assets within a protected area. This problem takes on particular significance across international borders and becomes challenging when the terrain is porous, rugged and treacherous in nature. Keeping an effective vigil against intruders on large tracts of land is a tedious task; currently, it is primarily performed by security personnel with automatic detection systems in passive supporting roles. This paper discusses an alternate autonomous approach by utilizing one or more Unmanned Vehicles (UVs), aided by smart sensors on the ground, to detect and localize an intruder. To facilitate autonomous UV operations, the region is equipped with Unattended Ground Sensors (UGSs) and laser fencing. Together, these sensors provide time-stamped location information (node and edge detection) of the intruder to a UV. For security reasons, we assume that the sensors are not networked (a central node can be disabled bringing the whole system down) and so, the UVs must visit the vicinity of the sensors to gather the information therein. This makes the problem challenging in that pursuit must be done with local and likely delayed information. We discretize time and space by considering a 2D grid for the area and unit speed for the UV, i.e. it takes one time unit to travel from one node to an adjacent node. The intruder is slower and takes two time steps to complete the same move. We compute the min–max optimal, i.e. minimum number of steps to capture the intruder under worst-case intruder actions, for different number of rows and columns in the grid and for both one and two pursuers.

The criterion of arising motion conflict of unmanned vehicles during implementing transportation plan in intelligent urban passenger transportation system

2020 ◽  
Vol 25 (3) ◽  
pp. 79-84
Author(s):  
Shviatsova A.V. ◽  
◽  
Shuts V.N. ◽  
Keyword(s):  
Transport System ◽  
Intelligent Systems ◽  
Historical Context ◽  
Unmanned Vehicles ◽  
Transport Systems ◽  
Passenger Transport ◽  
Electric Cars ◽  
The Matrix ◽  
Minimum Number ◽  
Transportation Plan

The proposed article is devoted to the description of an intelligent urban passenger transport system based on unmanned electric vehicles, sequentially moving along a separate line. This system is a passenger transport system of a new urban mobility, formed under the influence of social conditions generated by high population density in cities, that suppose the development of pedestrian zones and ecological modes of transport, "transport as a service", etc. In this historical context, public transport systems acquire special relevance. The described transport system belongs to intelligent systems, since it is capable of functioning in autonomous mode without human intervention, adaptively responding to changes in the dynamics of the flow of passengers during the day. Passengers are transported by electric cars, which can be combined into cassettes according to the principle of road trains based on the transportation plan drawn up by the intelligent center of the transport system according to the matrix of correspondences, filled in taking into account the incoming requests for service from passengers. When drawing up a transportation plan, the algorithms of the transport system give preference to transportation according to the "source-destination" principle, that is, when the passenger goes to the destination with a minimum number of intermediate stops, and ideally without them. The paper formulates also a criterion of arising of a conflict in the movement of vehicles, which allows to identify situations when an electric vehicle driving in front can detain vehicles following after. The work has relevance because the criterion will allow to make adjustments in the schedule of movement of vehicles and exclude the loss of time and energy that carries the transport system during braking and acceleration of electric cars, as well as to reduce waiting time and travel of passengers.

APPROXIMATION ALGORITHMS FOR A VARIANT OF DISCRETE PIERCING SET PROBLEM FOR UNIT DISKS

2013 ◽  
Vol 23 (06) ◽  
pp. 461-477 ◽  
Author(s):  
MINATI DE ◽  
GAUTAM K. DAS ◽  
PAZ CARMI ◽  
SUBHAS C. NANDY
Keyword(s):  
Approximation Algorithms ◽  
Simple Algorithm ◽  
Constant Factor ◽  
Performance Ratio ◽  
Approximation Result ◽  
Worst Case ◽  
Approximation Factor ◽  
Minimum Number ◽  
Unit Disks ◽  
Set Of Points

In this paper, we consider constant factor approximation algorithms for a variant of the discrete piercing set problem for unit disks. Here a set of points P is given; the objective is to choose minimum number of points in P to pierce the unit disks centered at all the points in P. We first propose a very simple algorithm that produces 12-approximation result in O(n log n) time. Next, we improve the approximation factor to 4 and then to 3. The worst case running time of these algorithms are O(n8 log n) and O(n15 log n) respectively. Apart from the space required for storing the input, the extra work-space requirement for each of these algorithms is O(1). Finally, we propose a PTAS for the same problem. Given a positive integer k, it can produce a solution with performance ratio [Formula: see text] in nO(k) time.

scholarly journals A NEURAL-VISUALIZATION IDS FOR HONEYNET DATA

2012 ◽  
Vol 22 (02) ◽  
pp. 1250005 ◽  
Author(s):  
ÁLVARO HERRERO ◽  
URKO ZURUTUZA ◽  
EMILIO CORCHADO
Keyword(s):  
Intelligent Systems ◽  
Visual Inspection ◽  
False Positive Rate ◽  
Projection Methods ◽  
Neural Models ◽  
Detection Systems ◽  
Security Personnel ◽  
Real Domain ◽  
Positive Rate ◽  
Attack Patterns

Neural intelligent systems can provide a visualization of the network traffic for security staff, in order to reduce the widely known high false-positive rate associated with misuse-based Intrusion Detection Systems (IDSs). Unlike previous work, this study proposes an unsupervised neural models that generate an intuitive visualization of the captured traffic, rather than network statistics. These snapshots of network events are immensely useful for security personnel that monitor network behavior. The system is based on the use of different neural projection and unsupervised methods for the visual inspection of honeypot data, and may be seen as a complementary network security tool that sheds light on internal data structures through visual inspection of the traffic itself. Furthermore, it is intended to facilitate verification and assessment of Snort performance (a well-known and widely-used misuse-based IDS), through the visualization of attack patterns. Empirical verification and comparison of the proposed projection methods are performed in a real domain, where two different case studies are defined and analyzed.

scholarly journals Motion compensation of short-range, wide-beam synthetic aperture radar

2011 ◽  
Vol 9 ◽  
pp. 61-66
Author(s):  
T. Reichthalhammer ◽  
E. Biebl
Keyword(s):  
Image Reconstruction ◽  
Motion Compensation ◽  
Short Range ◽  
Processing Time ◽  
Synthetic Aperture ◽  
Phase Reconstruction ◽  
Worst Case ◽  
Wide Beam ◽  
Detection Systems ◽  
Very High

Abstract. Up to now, SAR systems are a well known possibility for long-range detection. Applying them for short-range applications with wide-beam antennas, of course, does not increase the resolution but the probability to detect hidden targets with an anisotropic radar cross section significantly in comparison to other detection systems. Working with an appropriate wavelength even improves the possiblity to look through natural cover like grass. An application is detecting fawn while pasture mowing. The main issue in such applications is the antenna's motion in range direction as it is carried by cars or traction engines. If motion is not compensated, the phase cannot be reconstructed correctly, the resolution gets poorer and, in worst case, the target even disappears. Conventional methods for motion compensation either fail for wide beam antennas, since for contributions of wide angles the phase reconstruction is incorrect, or is not applicable for realtime data processing, because the processing time due to interpolation or similar steps is very high. We present a method of image reconstruction regarding motion of the antenna as well as wide beamwidth. This method is analyzed concerning processing time in comparison to the conventional image reconstruction. In our system we use a combination of algorithms. There is shown a comparison for different algorithms dependent of the antenna's motion and aperture angle.

scholarly journals Time-Motion Analysis of 6 Cystic Fibrosis Mutation Detection Systems

2005 ◽  
Vol 51 (7) ◽  
pp. 1116-1122 ◽  
Author(s):  
Amy E Krafft ◽  
Jack H Lichy
Keyword(s):  
Cystic Fibrosis ◽  
Motion Analysis ◽  
Stress Injury ◽  
Detection Systems ◽  
Time Motion ◽  
Assay Procedure ◽  
Minimum Number ◽  
Assay Time ◽  
Repetitive Stress ◽  
Time Required

Abstract Background: A dramatic increase in requests for routine cystic fibrosis (CF) carrier screening prompted us to conduct a time-motion analysis comparing commercially available CF testing platforms. Questions addressed in the study included: (a) How much time is required to perform each step involved in carrying out the assay procedure? (b) Which system requires the minimum number of manual manipulations to complete a typical run? (c) What workflow benefits can be achieved by automation? Methods: We used a 96-sample run for comparisons and analyzed each of the 6 methods to determine the number of pipetting steps and manual manipulations, the labor and instrument time, and the total time required to perform the assay. The survey participants included a staff of 4 technologists who perform complex molecular assays regularly. Time required for each procedure was determined by direct observation and from work logs completed by the technologists. Results: The total number of pipetting motions varied from 78 to 344. Labor time ranged from 2.6 to 8.4 h, and total assay time from 7.6 to 13.7 h. Conclusion: Time-motion analysis allowed identification of a method that minimized pipetting motions and thus reduced the risk of repetitive stress injury.

A Design-and-Build Project to Introduce Concepts Relating to Dimensional Variation

1998 ◽  
Vol 26 (4) ◽  
pp. 259-272
Author(s):  
S. M. Panton ◽  
P. R. Milner
Keyword(s):  
Classroom Environment ◽  
Tolerance Analysis ◽  
Cylinder Block ◽  
Worst Case ◽  
Good Design ◽  
Minimum Number ◽  
Dimensional Variation ◽  
Assembly Problem ◽  
Statistical Tolerance ◽  
Statistical Tolerance Analysis

A design-and-build project which has been used to introduce Year 2 students of Mechanical Engineering to the concepts of dimensional variation and the influence of dimensional variation on function and assembly. The project simulates the cylinder head cylinder block assembly problem and specifies requirements in terms of a tolerance on concentricity of the cylinders in the head and block, and the interchangeable assembly of the head and block. Materials which are easily and cheaply sourced and tools which are easily manufactured and safe to use in a classroom environment are used throughout. During the project the students are exposed to concepts such as worst-case and statistical tolerance analysis, sensitivity analysis, geometric moment effects, minimum constraint design, co-variance and gauging. The exercise also emphasizes that good design means components that function and assemble with the minimum number of tight tolerances.

scholarly journals Intruder capture algorithms considering visible intruders

2019 ◽  
Vol 16 (3) ◽  
pp. 172988141984673
Author(s):  
Jonghoek Kim
Keyword(s):  
Real Time ◽  
Weighted Graph ◽  
Search Algorithms ◽  
Tree Graph ◽  
Multiple Robots ◽  
Weighted Tree ◽  
Topological Map ◽  
Worst Case ◽  
Minimum Number ◽  
Full Knowledge

In this article, we consider the problem of using multiple robots (searchers) to capture intruders in an environment. Assume that a robot can access the position of an intruder in real time, that is, an intruder is visible by a robot. We simplify the environment so that robots and worst-case intruders move along a weighted graph, which is a topological map of the environment. In such settings, a worst-case intruder is characterized by unbounded speed, complete awareness of searcher location and intent, and full knowledge of the search environment. The weight of an edge or a vertex in a weighted graph is a cost describing the clearing requirement of the edge or the vertex. This article provides non-monotone search algorithms to capture every visible intruder. Our algorithms are easy to implement, thus are suitable for practical robot applications. Based on the non-monotone search algorithms, we derive the minimum number of robots required to clear a weighted tree graph. Considering a general weighted graph, we derive bounds for the number of robots required. Finally, we present switching algorithms to improve the time efficiency of capturing intruders while not increasing the number of robots. We verify the effectiveness of our approach using MATLAB simulations.

scholarly journals On Compact Encoding of Pagenumber $k$ Graphs

2008 ◽  
Vol Vol. 10 no. 3 ◽  
Author(s):  
Cyril Gavoille ◽  
Nicolas Hanusse
Keyword(s):  
Lower Bound ◽  
Upper Bound ◽  
Constant Time ◽  
Worst Case ◽  
Encoding Scheme ◽  
Information Theoretic ◽  
Auxiliary Table ◽  
Minimum Number ◽  
International Audience

International audience In this paper we show an information-theoretic lower bound of kn - o(kn) on the minimum number of bits to represent an unlabeled simple connected n-node graph of pagenumber k. This has to be compared with the efficient encoding scheme of Munro and Raman of 2kn + 2m + o(kn+m) bits (m the number of edges), that is 4kn + 2n + o(kn) bits in the worst-case. For m-edge graphs of pagenumber k (with multi-edges and loops), we propose a 2mlog2k + O(m) bits encoding improving the best previous upper bound of Munro and Raman whenever m ≤ 1 / 2kn/log2 k. Actually our scheme applies to k-page embedding containing multi-edge and loops. Moreover, with an auxiliary table of o(m log k) bits, our coding supports (1) the computation of the degree of a node in constant time, (2) adjacency queries with O(logk) queries of type rank, select and match, that is in O(logk *minlogk / loglogm, loglogk) time and (3) the access to δ neighbors in O(δ) runs of select, rank or match;.

scholarly journals An Executive Approach to Achieve Mutual Exclusion in Distributed Data using Topology and Association Rule.

2014 ◽  
Vol 13 (6) ◽  
pp. 4537-4542
Author(s):  
Mr. Anurag Singh ◽  
Dr. Amod Tiwari
Keyword(s):  
Distributed System ◽  
Association Rule ◽  
Message Passing ◽  
Computer Network ◽  
Mutual Exclusion ◽  
Distributed Data ◽  
Worst Case ◽  
New Approach ◽  
And Topology ◽  
Minimum Number

In this paper, a new approach is being proposed to achieve mutual exclusion in distributed system using computer network and topology of nth nodes. In this executive approach nodes communicate among themselves using message passing technique. In this executive approach, distributed system with n nodes is logically partitioned into number of sub distributed system having only m½ nodes, where m is obtained by adding a minimum number in n to make it next perfect square number only if n is not a perfect square. Proposed algorithm is a Token based approach and achieves token optimally in 2 messages only for the best case and in worst case a node achieves token in n messages only.

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