Security and Communication Distance Improvement in Decoy States Based Quantum Key Distribution Using Pseudo-Random Bases Choice for Photon Polarization Measurement

This paper proposes a new quantum key distribution(QKD) protocol, namely the pseudo-random bases entangled photon based QKD (PRB-EPQKD) protocol. The latest mainly focuses on three properties, including the security of the protocol, the secure key size and the maximum communication distance between legitimate communication users (Alice and Bob). To achieve this, we first consider a spontaneous-parametric-down (SPDC) photon source located in a low-earth-orbit (LEO) type satellite capable of producing and distributing entangled photons pairs to Alice and Bob. Secondly, we assume that Alice's and Bob's photons state measurement bases are identically generated via a pseudo-random number generator (PRNG), namely the quantum logistic map (QLM). Finally, we also assume that in addition to their photons states, Alice and Bob intentionally share a set of decoy states at each pulse with randomly selected intensity, and with the goal to detect the presence of the eavesdropper (Eve). Under these considerations, the secure key rate upper bound is evaluated applying the Gottesman-Lo-Lutkenhaus-Preskill's (GLLP) formula, for two different implementations, namely the non-decoy states and the infinite active decoy states based QKD. It is observed a significant improvement in the secure key size and the communication distance as well, compared to existing protocols, since we realize that under daylight, downlinks satellite conditions, a kindly selected light source, and good crystal's properties, the maximum communication distance can reach up to 70000 km. In addition, using the combined type-I and type-II SPDC photons source as our entangled photons pairs generator, significantly improved the photon mean number and render our protocol more robust against photon number division attack and against attenuation-induced atmospheric propagation. Furthermore, the protocol is more secure as compared to existing ones, given that any eavesdropper must crack simultaneously the chaotic system used as PRNG and the QKD system, before getting any useful information as regards to the measurement bases used by Alice and Bob, and thus the secure key.

The principles underlying the IFRS and the measurement bases of the elements comprising the financial statements

Purpose: This theoretical essay seeks to present concepts, arguments and discussions about the adoption and use of IFRS, focusing on their underlying principles and measurement bases. Methodology: Literature review with presentation and discussion of arguments from authors who have researched the use of IFRS and its underlying principles and measurement bases. Results: Principle-based accounting standards are seen by a number of authors as a possible solution to the problem of accounting harmonization. However, another stream of authors states that principle-based accounting standardization, although it may result in higher quality it is less assertive financial reporting, given the existence of subjectivity in the content of financial statements. This fact leads to the conclusion that absolute harmonization of accounting standards would be impossible. Contributions of the Study: The study proposes notes regarding the discussion on IFRS, which are responsible for increasing the quality of financial statements, while at the same time reducing the reliability of the information produced, in view of the difficulties inherent to the application of the concept of fair value.

Mutually unbiased unextendible maximally entangled bases in Cd ⊗ Cq(d+1)

Quantum measurements based on mutually unbiased base (MUB) are commonly used in quantum information processing. Firstly, we construct two completed unextendible maximally entangled bases (UMEBs) in bipartite systems [Formula: see text]. Then, the sufficient and necessary conditions of these two UMEBs develop into MUB can be obtained. Finally, we present some UMEBs that are mutually unbiased in concrete bipartite systems. These results provide a method to construct the best measurement bases.

Is accounting ready for the dual measurement in the statement of financial position and the statement of profit or loss? Content analysis of comment letters to the Exposure Draft of the Conceptual Framework

The aim of the paper is to study the responses of the IASB constituents to the Exposure Draft of the Conceptual Framework, given on the proposed matter of dual measurement for the statement of financial position and the statement of profit or loss, and to assess their potential impact on standard-setting and accounting practice. The authors briefly analysed the literature about measurement bases and then presented the results of their empirical research. The research methodology involves mainly content analysis of comment letters sent to the IASB in response to the Exposure Draft of the Conceptual Framework. On the basis of the gathered data, the authors concluded that despite the positive feedback that the proposal received, the number of suggestions made and the concerns it provoked may lead to the conclusion that the concept was introduced too early and thus not developed well. The IASB did not provide enough justification behind their proposal. The Board seems more interested in enforcing certain solutions than actually dealing with the problems related to them. The lack of a clear conceptual concept behind the dual measurement basis may cause it to remain rather an ad hoc tool used to forge a compromise. It may even be seen just as a post factum description of inconsistently applied measurement bases in IFRS.

Accounting for What We Treasure

Recent attempts to include and assess public heritage in the accounts of governments and charities are controversial. There are many kinds of value, not merely financial, and various measurement bases. This chapter examines why and how we account (if at all) for heritage assets bringing out the surrounding controversy. Is public heritage an asset that should be included in the reported wealth of public bodies and nations? The economic valuation methods, revealed preferences and stated preferences are the economic valuation methods investigated and considered in relation to the decisions to be made on public heritage. Although the conceptual and practical problems surrounding valuation and reporting of public heritage are immense, pragmatic solutions should be sought. Multidisciplinary approaches are necessary to make informed decisions on management, financing, and the allocation of resources for public heritage.

Challenges to the Users of Financial Reports Constructed Using Multiple Measurement Bases: A Review of the IASB’s Conceptual Framework for Financial Reporting

The IASB’s conceptual framework for financial reporting identifies multiple measurement bases and concludes that an entity may employ more than one measurement base in constructing the financial reports. The framework further clarify situations as to how the preparers will proceed in constructing the entity’s financial report where the preparers are satisfied that a piece of information is relevant to the users of financial reports, but is subject to a high degree of measurement uncertainty. The purpose of this paper is to critically evaluate the choice of multiple measurement bases in the conceptual framework and highlight the challenges posed to a user of financial reports who seeks to obtain insights into an entity’s financial performance and position through reading reports constructed using an eclectic approach to measurement.

Quantum key distribution with mismatched measurements over arbitrary channels

In this paper, we derive key-rate expressions for different quantum key distribution protocols. Our key-rate equations utilize multiple channel statistics, including those gathered from mismatched measurement bases - i.e., when Alice and Bob choose incompatible bases. In particular, we will consider an Extended B92 and a two-way semi-quantum protocol. For both these protocols, we demonstrate that their tolerance to noise is higher than previously thought - in fact, we will show the semi-quantum protocol can actually tolerate the same noise level as the fully quantum BB84 protocol. Along the way, we will also consider an optimal QKD protocol for various quantum channels. Finally, all the key-rate expressions which we derive in this paper are applicable to any arbitrary, not necessarily symmetric, quantum channel.