771 research outputs found
More Communication with Less Entanglement
We exhibit the intriguing phenomena of "Less is More" using a set of
multipartite entangled states. We consider the quantum communication protocols
for the {\em exact} teleportation, superdense coding, and quantum key
distribution. We find that sometimes {\em less} entanglement is {\em more}
useful. To understand this phenomena we obtain a condition that a resource
state must satisfy to communicate a -qubit pure state with terms. We
find that the an appropriate partition of the resource state should have a
von-Neumann entropy of . Furthermore, it is shown that some
states may be suitable for exact superdense coding, but not for exact
teleportation.Comment: 7 pages, 1 tabl
Two-qubit mixed states and teleportation fidelity: Purity, concurrence, and beyond
To explore the properties of a two-qubit mixed state, we consider quantum
teleportation. The fidelity of a teleported state depends on the resource state
purity and entanglement, as characterized by concurrence. Concurrence and
purity are functions of state parameters. However, it turns out that a state
with larger purity and concurrence, may have comparatively smaller fidelity. By
computing teleportation fidelity, concurrence and purity for two-qubit
X-states, we show it explicitly. We further show that fidelity changes
monotonically with respect to functions of parameters - other than concurrence
and purity. A state with smaller concurrence and purity, but larger value of
one of these functions has larger fidelity. These functions, thus characterize
nonlocal classical and/or quantum properties of the state that are not captured
by purity and concurrence alone. In particular, concurrence is not enough to
characterize the entanglement properties of a two-qubit mixed state
Resource state structure for controlled quantum key distribution
Quantum entanglement plays a pivotal role in many communication protocols,
like secret sharing and quantum cryptography. We consider a scenario where more
than two parties are involved in a protocol and share a multipartite entangled
state. In particular, we considered the protocol of Controlled Quantum Key
Distribution (CoQKD), introduced in the Ref. Chin. Phys. Lett. 20, 183-185
(2003), where, two parties, Alice and Bob establish a key with the cooperation
of other parties. Other parties control/supervise whether Alice and Bob can
establish the key, its security and key rate. We discuss the case of three
parties in detail and find suitable resource states. We discuss the controlling
power of the third party, Charlie. We also examine the usefulness of the new
resource states for generating conference key and for cooperative
teleportation. We find that recently introduced Bell inequalities can be useful
to establish the security of the conference key. We also generalize the
scenario to more than three parties.Comment: 11 pages, 7 figures. Close to published versio
Extracting Entities of Interest from Comparative Product Reviews
This paper presents a deep learning based approach to extract product
comparison information out of user reviews on various e-commerce websites. Any
comparative product review has three major entities of information: the names
of the products being compared, the user opinion (predicate) and the feature or
aspect under comparison. All these informing entities are dependent on each
other and bound by the rules of the language, in the review. We observe that
their inter-dependencies can be captured well using LSTMs. We evaluate our
system on existing manually labeled datasets and observe out-performance over
the existing Semantic Role Labeling (SRL) framework popular for this task.Comment: Source Code:
https://github.com/jatinarora2702/Review-Information-Extractio
Green Cellular Network Deployment To Reduce RF Pollution
As the mobile telecommunication systems are growing tremendously all over the
world, the numbers of handheld and base stations are also rapidly growing and
it became very popular to see these base stations distributed everywhere in the
neighborhood and on roof tops which has caused a considerable amount of panic
to the public in Palestine concerning wither the radiated electromagnetic
fields from these base stations may cause any health effect or hazard. Recently
UP High Court in India ordered for removal of BTS towers from residential area,
it has created panic among cellular communication network designers too. Green
cellular networks could be a solution for the above problem. This paper deals
with green cellular networks with the help of multi-layer overlaid hierarchical
structure (macro / micro / pico / femto cells). Macrocell for area coverage,
micro for pedestrian and a slow moving traffic while pico for indoor use and
femto for individual high capacity users. This could be the answer of the
problem of energy conservation and enhancement of spectral density also.Comment: 6 pages, 6 figures. arXiv admin note: substantial text overlap with
arXiv:1204.2101, arXiv:1110.2627, and with arXiv:0803.0952 and
arXiv:0803.0952 by other author
Effect of Spacer and the Enzyme-Linked Immunosorbent Assay
The effect of spacers and the enzyme-linked immunosorbent assay (ELISA) formats on the functional parameters of assays such as lower detection limit, inhibitory concentration at 50 per cent (IC50), and specificity were studied. Enzyme conjugates having hydrophobic and hydrophilic spacers were prepared using O-isopropyl methylphosphonic acid (IMPA) and horseradish peroxidase (HRP) as an enzyme label. Comparison was made with reference to enzyme conjugate without any spacer. The present investigation revealed that the presence of a hydrophilic spacer in the enzyme conjugate significantly improves the sensitivity of assays. An enhanced IC50 value achieved was 0.01 μg mL−1 for free antigen detection by direct immunoassay using hydrophilic spacers and precoating of ELISA plates by secondary antibody. The use of a hydrophilic spacer might have helped in projecting the hapten in the aqueous phase, leading to enhanced antibody binding signal and improved sensitivity of the assay
Intrinsic Measures and Shape Analysis of the Intratemporal Facial Nerve
Hypothesis: To characterize anatomical measurements and shape variation of the facial nerve within the temporal bone, and to create statistical shape models (SSMs) to enhance knowledge of temporal bone anatomy and aid in automated segmentation.
Background: The facial nerve is a fundamental structure in otologic surgery, and detailed anatomic knowledge with surgical experience are needed to avoid its iatrogenic injury. Trainees can use simulators to practice surgical techniques, however manual segmentation required to develop simulations can be time consuming. Consequently, automated segmentation algorithms have been developed that use atlas registration, SSMs, and deep learning.
Methods: Forty cadaveric temporal bones were evaluated using three dimensional microCT (μCT) scans. The image sets were aligned using rigid fiducial registration, and the facial nerve canals were segmented and analyzed. Detailed measurements were performed along the various sections of the nerve. Shape variability was then studied using two SSMs: one involving principal component analysis (PCA) and a second using the Statismo framework.
Results: Measurements of the nerve canal revealed mean diameters and lengths of the labyrinthine, tympanic, and mastoid segments. The landmark PCA analysis demonstrated significant shape variation along one mode at the distal tympanic segment, and along three modes at the distal mastoid segment. The Statismo shape model was consistent with this analysis, emphasizing the variability at the mastoid segment. The models were made publicly available to aid in future research and foster collaborative work.
Conclusion: The facial nerve exhibited statistical variation within the temporal bone. The models used form a framework for automated facial nerve segmentation and simulation for trainees
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