Current Issue : July - September Volume : 2018 Issue Number : 3 Articles : 5 Articles
An experiment is proposed in which the overall path taken by a photon is indicated\nby the timing of a twin herald photon, while a particular segment\nof that path is determined by interference. The needed coincident pairs of\nphotons are generated by type I spontaneous-parametric-down-conversion\n(SPDC) and diffraction-selected by a grating at the frequency of a two-photon\nstate. This is to be divided into two one-photon states of high coherence\nlength. Upon experimental confirmation that their count coincidences have\nbeen maintained, the two single photons are to be used as a timing herald and\nsource for an unequal path interferometer. A photon�s path through the interferometer\nvia a short arm is indicated by count synchronization with the\nherald. The exit output port used and resulting final detection location are\ndetermined by the phase in the long arm. If output port usage can be controlled\nby the phase in the photon-free arm, the path of the photon as particle\nwill have been controlled by interference with an accompanying photon-\nempty wave....
Context: Derivations for the relativity formulations for the Lorentz are conventionally\nbased on continuum mechanics. Purpose: This paper derives the\nformulations from a particle perspective. Approach: A non-local hidden-\nvariable (NLHV) approach is adopted, based on the specific particle\nstructures of the Cordus Theory. Findings: The Lorentz and relativistic\nDoppler formulations are shown to be derivable from a NLHV particle perspective.\nUnexpectedly, the equations contain an additional term relating to\nthe difference in the distribution of matter (fabric density) between situations.\nFor a homogenous fabric, which is the assumption of general relativity, the\nconventional formulations are recovered. Originality: The novel contribution\nis deriving the relativistic formulation from a NLHV theory. Also novel is the\nidentification of the fabric density as a term in the Lorentz. Implications: It is\npredicted that inertial frames of reference are only situationally equivalent in\nthe special case where they also have the same fabric density. We find against\nthe cosmological principle with its assumption of homogeneity. The resulting\nsituational theory of relativity has further implications for interpreting gravitational\ninteractions at the galactic scale and larger....
The ubiquity of instant messaging services on mobile devices and their use of\nend-to-end encryption in safeguarding the privacy of their users have become\na concern for some governments. WhatsApp messaging service has emerged\nas the most popular messaging app on mobile devices today. It uses end-to-end\nencryption which makes government and secret services efforts to combat organized\ncrime, terrorists, and child pornographers technically impossible.\nGovernments would like a ââ?¬Å?backdoorââ?¬Â into such apps, to use in accessing\nmessages and have emphasized that they will only use the ââ?¬Å?backdoorââ?¬Â if there\nis a credible threat to national security. Users of WhatsApp have however, argued\nagainst a ââ?¬Å?backdoorââ?¬Â; they claim a ââ?¬Å?backdoorââ?¬Â would not only be an infringement\nof their privacy, but that hackers could also take advantage of it. In\nlight of this security and privacy conflict between the end users of WhatsApp\nand governmentââ?¬â?¢s need to access messages in order to thwart potential terror\nattacks, this paper presents the advantages of maintaining E2EE in WhatsApp\nand why governments should not be allowed a ââ?¬Å?backdoorââ?¬Â to access usersââ?¬â?¢\nmessages. This research presents the benefits encryption has on consumer security\nand privacy, and also on the challenges it poses to public safety and national\nsecurity....
Microstrip patch antenna (MPA) is widely implemented in different communication\nsystems. One of the main disadvantages of MPA which limits its applications\nis its narrow bandwidth. In this paper I enhanced the bandwidth of\nMPA by inserting multiple slots in its ground plane. I used FR-4 substrate to\ndesign this antenna. The dimensions of this antenna are 59 mm and 79 mm.\nThe dielectric constant is 4.4 and the height is 1.6 mm. I inserted up to 15\nslots in ground plane with 1mm width. The spacing between slots is 3 mm. I\ninvestigated two designs. In the first design, slots were arranged in parallel to\nthe feeding line. In the second one, slots were arranged horizontally to the\nfeeding line. The main objective of this paper is to design and simulate MPA\nsuitable for wide number of applications. Antenna bandwidth improvement is\n18%. All the simulations were obtained by using HFSS simulator....
The first application of utilizing unique information-fusion SLAM (IF-SLAM) methods is developed for mobile robots performing\nsimultaneous localization and mapping (SLAM) adapting to search and rescue (SAR) environments in this paper. Several fusion\napproaches, parallel measurements filtering, exploration trajectories fusing, and combination sensors� measurements and mobile\nrobots� trajectories, are proposed. The novel integration particle filter (IPF) and optimal improved EKF (IEKF) algorithms are\nderived for information-fusion systems to perform SLAM task in SAR scenarios. The information-fusion architecture consists\nof multirobots and multisensors (MAM); multiple robots mount on-board laser range finder (LRF) sensors, localization sonars,\ngyro odometry, Kinect-sensor, RGB-D camera, and other proprioceptive sensors. This information-fusion SLAM (IF-SLAM) is\ncompared with conventional methods, which indicates that fusion trajectory is more consistent with estimated trajectories and real\nobservation trajectories. The simulations and experiments of SLAM process are conducted in both cluttered indoor environment\nand outdoor collapsed unstructured scenario, and experimental results validate the effectiveness of the proposed information fusion\nmethods in improving SLAM performances adapting to SAR scenarios....
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