Moving to the West: Media, Cultural Transnationalism and Identity. Cultural Dynamics of Korean Women in Diaspora

This research project explores the experiences of young Korean women relocating to London, employing an ethnographically informed approach to delve into media, diasporic identity, and cultural transnationalism. The analysis draws from six month of intensive fieldwork, including “following” in-depth interviews, participant observation, and digital ethnography. The study aims to investigate the interplay between media, social values, interactions, and the performance of identities within the Korean female diasporic community in the context of circulation and transnational migration. The primary objective is to discern how social values and interactions, whether mediated or direct, contribute to the cultural transmission within Korean female diasporic groups and shape specific meanings associated with transnational identities. Within this framework, meta-themes such as transnational imagination, Western centrism, alternative multicultural interpretations, and performativity emerged, guiding further data analysis. The research findings underscore the pivotal role of media in shaping the imagination that prompts young Korean women’s transnational mobility. Additionally, it reveals the complex contradictions within their transnational social spheres, fostering a unique symbolic transnational space where identity politics continuously evolve through negotiation and struggle. This study offers a comprehensive examination of cultural transnationalism, spotlighting a contemporary migration pattern. It showcases the correlation between media, non-Western contexts, Western centrism, identity, and everyday transnational experiences. At a micro level, this analysis fills significant research gaps regarding the intersectionality of transnationalism, media, and migration studies within the narrative of young Korean women’s transnational experiences

On the minimum degree of minimally t t -tough, claw-free graphs

A graph $G$ is minimally $t$-tough if the toughness of $G$ is $t$ and deletion of any edge from $G$ decreases its toughness. Katona et al. conjectured that the minimum degree of any minimally $t$-tough graph is $\lceil 2t\rceil$ and proved that the minimum degree of minimally $\frac{1}2$-tough and $1$-tough, claw-free graphs is 1 and 2, respectively. We have show that every minimally $3/2$-tough, claw-free graph has a vertex of degree of $3$. In this paper, we give an upper bound on the minimum degree of minimally $t$-tough, claw-free graphs for $t\geq 2$

Constrained stochastic LQ control with regime switching and application to portfolio selection

This paper is concerned with a stochastic linear-quadratic optimal control problem with regime switching, random coefficients, and cone control constraint. The randomness of the coefficients comes from two aspects: the Brownian motion and the Markov chain. Using It\^{o}'s lemma for Markov chain, we obtain the optimal state feedback control and optimal cost value explicitly via two new systems of extended stochastic Riccati equations (ESREs). We prove the existence and uniqueness of the two ESREs using tools including multidimensional comparison theorem, truncation function technique, log transformation and the John-Nirenberg inequality. These results are then applied to study mean-variance portfolio selection problems with and without short-selling prohibition with random parameters depending on both the Brownian motion and the Markov chain. Finally, the efficient portfolios and efficient frontiers are presented in closed forms

Comparison theorems for multi-dimensional BSDEs with jumps and applications to constrained stochastic linear-quadratic control

In this paper, we, for the first time, establish two comparison theorems for multi-dimensional backward stochastic differential equations with jumps. Our approach is novel and completely different from the existing results for one-dimensional case. Using these and other delicate tools, we then construct solutions to coupled two-dimensional stochastic Riccati equation with jumps in both standard and singular cases. In the end, these results are applied to solve a cone-constrained stochastic linear-quadratic and a mean-variance portfolio selection problem with jumps. Different from no jump problems, the optimal (relative) state processes may change their signs, which is of course due to the presence of jumps

Constrained monotone mean-variance problem with random coefficients

This paper studies the monotone mean-variance (MMV) problem and the classical mean-variance (MV) problem with convex cone trading constraints in a market with random coefficients. We provide semiclosed optimal strategies and optimal values for both problems via certain backward stochastic differential equations (BSDEs). After noting the links between these BSDEs, we find that the two problems share the same optimal portfolio and optimal value. This generalizes the result of Shen and Zou $[$ SIAM J. Financial Math., 13 (2022), pp. SC99-SC112$]$ from deterministic coefficients to random ones

Design Impedance Mismatch Physical Unclonable Functions for IoT Security

We propose a new design, Physical Unclonable Function (PUF) scheme, for the Internet of Things (IoT), which has been suffering from multiple-level security threats. As more and more objects interconnect on IoT networks, the identity of each thing is very important. To authenticate each object, we design an impedance mismatch PUF, which exploits random physical factors of the transmission line to generate a security unique private key. The characteristic impedance of the transmission line and signal transmission theory of the printed circuit board (PCB) are also analyzed in detail. To improve the reliability, current feedback amplifier (CFA) method is applied on the PUF. Finally, the proposed scheme is implemented and tested. The measure results show that impedance mismatch PUF provides better unpredictability and randomness

Efficient thermo-spin conversion in van der Waals ferromagnet FeGaTe

Recent discovery of 2D van der Waals (vdW) magnetic materials has spurred progress in developing advanced spintronic devices. A central challenge lies in enhancing the spin-conversion efficiency for building spin-logic or spin-memory devices. We systematically investigated the anomalous Hall effect and anomalous Nernst effect in above-room-temperature van der Waals ferromagnet FeGaTe with perpendicular anisotropy, uncovering significant spin-conversion effects. The anomalous Hall effect demonstrated an efficient electric spin-charge conversion, with a notable spin Hall angle of 6 $\%$ - 10.38 $\%$. The temperature-dependent behavior of the anomalous Nernst voltage primarily results from the thermo-spin conversion. Uniquely, we have experimentally achieved thermo-spin polarization values of over 690 $\%$ at room temperature and extremely large of 4690 $\%$ at about 93 K. This study illuminates the potential of vdW ferromagnets in advancing efficient spin conversion devices.Comment: 26 pages, 11 figure

LQ Optimal Control of First-Order Hyperbolic PDE Systems with Final State Constraints

This paper studies the linear-quadratic (LQ) optimal control problem of a class of systems governed by the first-order hyperbolic partial differential equations (PDEs) with final state constraints. The main contribution is to present the solvability condition and the corresponding explicit optimal controller by using the Lagrange multiplier method and the technique of solving forward and backward partial differential equations (FBPDEs). In particular, the result is reduced to the case with zero-valued final state constraints. Several numerical examples are provided to demonstrate the performance of the designed optimal controller