2,974 research outputs found
Identity construction through gendered terms of addresses in Korean
How should a speaker call a hearer? In this paper, we present an experimental study which probes the social and interactional meaning of Korean gendered terms of addresses (GTAs: unnie, oppa, noona, hyung). GTAs prescriptively index genders of both interlocutors, but are beginning to be used in ‘gender- mismatch’ patterns. Based on the experimental results, we argue that both the prescription conforming and the ‘mismatching’ uses of GTAs are each associated with unique, complex webs of meanings which track the shifting gender ideologies in Korea. In particular, mismatching uses of GTAs are shown to often function as speakers’ strategy to break away from established gender norms, including traditional gender roles and the sexualization of female-male relations
Fabrication of Highly Aligned Poly(Vinyl Alcohol) Nanofibers and its Yarn by Electrospinning
In the conventional electrospinning method, fibers are randomly deposited and form nonwoven structures; however, highly aligned micro- or nanofiber and its yarn may only be applicable for the fields, including composites, clothing, textiles, and microelectronics. The elementary principle to obtain uniaxially arranged nanofiber array is to regulate the electric field distribution by using assistant electrode or modified collecting device. The potential applications of conventional electrospun poly(vinyl alcohol) (PVA) fiber in the preparation of ultrafine separation filters, biodegradable mats, etc., have been described by many researchers. Highly aligned PVA nanofibers were prepared using a modified electrospinning process at the optimum conditions, and a twister added modified electrospinning apparatus was used to prepare twisted nanofiber yarn. The diameter and arrangement of the electrospun PVA nanofibers were characterized using FE-SEM. To study the effect of applied voltage and rotational velocity on the alignment rate of the nanofibers, different voltages and rotational velocity were applied during modified electrospinning, keeping other parameters unchanged. To measure the melting temperature and crystallinity of aligned nanofibers, differential scanning calorimetry and X-ray diffraction measurement were performed, respectively. The fabricated highly aligned nanofiber and its yarn might have a practical use of devices for microelectronics
Strong and Reversible Adhesion of Interlocked 3D-Microarchitectures
Diverse physical interlocking devices have recently been developed based on one-dimensional (1D), high-aspect-ratio inorganic and organic nanomaterials. Although these 1D nanomaterial-based interlocking devices can provide reliable and repeatable shear adhesion, their adhesion in the normal direction is typically very weak. In addition, the high-aspect-ratio, slender structures are mechanically less durable. In this study, we demonstrate a highly flexible and robust interlocking system that exhibits strong and reversible adhesion based on physical interlocking between three-dimensional (3D) microscale architectures. The 3D microstructures have protruding tips on their cylindrical stems, which enable tight mechanical binding between the microstructures. Based on the unique 3D architectures, the interlocking adhesives exhibit remarkable adhesion strengths in both the normal and shear directions. In addition, their adhesion is highly reversible due to the robust mechanical and structural stability of the microstructures. An analytical model is proposed to explain the measured adhesion behavior, which is in good agreement with the experimental results
Frequency limits of sequential readout for sensing AC magnetic fields using nitrogen-vacancy centers in diamond
The nitrogen-vacancy (NV) centers in diamond have ability to sense
alternating-current (AC) magnetic fields with high spatial resolution. However,
the frequency range of AC sensing protocols based on dynamical decoupling (DD)
sequences has not been thoroughly explored experimentally. In this work, we
aimed to determine the sensitivity of ac magnetic field as a function of
frequency using sequential readout method. The upper limit at high frequency is
clearly determined by Rabi frequency, in line with the expected effect of
finite DD-pulse width. In contrast, the lower frequency limit is primarily
governed by the duration of optical repolarization rather than the decoherence
time (T) of NV spins. This becomes particularly crucial when the repetition
(dwell) time of the sequential readout is fixed to maintain the acquisition
bandwidth. The equation we provide successfully describes the tendency in the
frequency dependence. In addition, at the near-optimal frequency of 1 MHz, we
reached a maximum sensitivity of 229 pT/ by employing the
XY4-(4) DD sequence.Comment: 7 pages, 5 figure
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