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This work proposes a digital quantum simulation protocol for the linear scattering process of bosons, which provides a simple extension to partially distinguishable boson cases. Our protocol is achieved by combining the boson-fermion correspondence relation and fermion to qubit encoding protocols. As a proof of concept, we designed quantum circuits for generating the Hong-Ou-Mandel dip by varying particle distinguishability. The circuits were verified with the classical and quantum simulations using the IBM Quantum and IonQ cloud services.

Because military special forces carry out dangerous missions, they are much more exposed to adversities and traumatic events compared to other occupational groups. According to Posttraumatic Growth theory, individuals tend to obtain positive growth through adversities. Moreover, a framework of Psychosocial Gains from Adversity argues not only individual changes but also social changes in the group to which the individual belongs are induced. Therefore, the present study aimed to explore the adverse experiences of special forces operatives and delineate the positive shift at an individual and social level via Consensual Qualitative Research (CQR). Eight individuals serving in special forces at the Korean Army, Navy and Air Force were interviewed using a semi-structured protocol. Four domains including 10 categories and 34 subcategories were identified: (a) Adverse experiences; (b) Personal change; (c) Social change; and (d) Attributes related to adverse experience. The findings and clinical implications are discussed in light of growth over facing adversities and interaction between personal and social factors., Author(s): Junsang Park [sup.1] , Jungmin Lee [sup.2] , Daewon Kim [sup.1] , Joonsuk Kim [sup.3] Author Affiliations: (1) grid.31501.36, 0000 0004 0470 5905, Department of Education, Seoul National University, [...]

In this paper, we propose a parametric finite impulse response (FIR) channel identification algorithm, apply the algorithm to a multichannel maximum likelihood sequential estimation (MLSE) equalizer using multiple antennas, and investigate the improvement in the overall bit error rate (BER) performance. By exploring the structure of the specular multipath channels, we are able to reduce the number of channel parameters to provide a better channel estimate for the MLSE equalizer. The analytic BER lower bounds of the proposed algorithm as well as those of several other conventional MLSE algorithms in the specular multipath Rayleigh-fading channels are derived. In the derivation, we consider the channel mismatch caused by the additive Gaussian noise and the finite-length channel approximation error. A handy-to-use simplified BER lower bound is also derived. Simulation results that illustrate the BER performance of the proposed algorithm in the global system for mobile communications (GSM) system are presented and compared to the analytic lower bounds. Index Terms--Channel mismatch, MLSE, parametric channel model.

A method based on the Z -transform is demonstrated to cascade transmission line sections of unequal lengths and achieve multiband and/or wideband properties. Unlike previous methods based on the Z -transform, the proposed method associates the z^-1 term with the infinitesimal length of the unit segment. Consequently, any electrical length can be expressed in the z^-1 form. Therefore, while the previous methods are restricted to cascading lines of a commensurate length only, the proposed method can be applied to those of incommensurate lengths. Furthermore, the $z$ -polynomials for triple or more bands can be constructed by multiplying a combination of single- and dual-band polynomials, which remarkably simplifies the entire procedure to develop multiband and/or wideband circuits with virtually no limitation in terms of the number and/or combination of frequencies. The validity and practicality of the proposed method is verified with experimental results for various impedance transformers for real loads and Wilkinson power dividers; the results show the independence in the number and combination of operating frequencies as well as a dual-band operation with a center frequency ratio as large as 7.75. [ABSTRACT FROM AUTHOR]

IEEE 802.11, which designs wireless local area networks (WLAN), is one of the most successful standards in wireless communication systems. In this article, we review the history of WLAN standards, and provide technical overviews of the recent development of WLAN systems. Especially, as the original inventor and the proposer, we focus on beamforming and compressed feedback schemes, which have been adopted in 802.11 WLAN standards, to improve the throughput for a multiple-input multiple-output (MIMO) system. These techniques are essential to maximize the downlink system throughput for multiple user transmission as well as for single user transmission. Also, we present discussions on new technologies to further enhance user throughput, which are currently considered for future WLAN systems. [ABSTRACT FROM PUBLISHER]