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991.
Junaid ur Rehman Ahmad Farooq Youngmin Jeong Hyundong Shin 《Quantum Information Processing》2018,17(10):271
We address the problem of unambiguous discrimination of quantum channels (UDQC) without entanglement. As our main result, we show that even in the absence of entanglement, partial UDQC (PUDQC) can still be performed—depending on the unknown given channel. We provide a necessary and sufficient condition for PUDQC and put forth a method to perform the PUDQC once the said condition is met. We propose the performance metrics that capture the expected performance of the PUDQC independent of the specific channels to be distinguished. Finally, we perform PUDQC on several qubit channel pairs as concrete examples and derive the proposed performance metrics for these channel pairs. 相似文献
992.
A Projection Method for the Conservative Discretizations of Parabolic Partial Differential Equations
We present a projection method for the conservative discretizations of parabolic partial differential equations. When we solve a system of discrete equations arising from the finite difference discretization of the PDE, we can use iterative algorithms such as conjugate gradient, generalized minimum residual, and multigrid methods. An iterative method is a numerical approach that generates a sequence of improved approximate solutions for a system of equations. We repeat the iterative algorithm until a numerical solution is within a specified tolerance. Therefore, even though the discretization is conservative, the actual numerical solution obtained from an iterative method is not conservative. We propose a simple projection method which projects the non-conservative numerical solution into a conservative one by using the original scheme. Numerical experiments demonstrate the proposed scheme does not degrade the accuracy of the original numerical scheme and it preserves the conservative quantity within rounding errors. 相似文献
993.
In this work we study the parallel coordinate descent method (PCDM) proposed by Richtárik and Taká? [Parallel coordinate descent methods for big data optimization, Math. Program. Ser. A (2015), pp. 1–52] for minimizing a regularized convex function. We adopt elements from the work of Lu and Xiao [On the complexity analysis of randomized block-coordinate descent methods, Math. Program. Ser. A 152(1–2) (2015), pp. 615–642], and combine them with several new insights, to obtain sharper iteration complexity results for PCDM than those presented in [Richtárik and Taká?, Parallel coordinate descent methods for big data optimization, Math. Program. Ser. A (2015), pp. 1–52]. Moreover, we show that PCDM is monotonic in expectation, which was not confirmed in [Richtárik and Taká?, Parallel coordinate descent methods for big data optimization, Math. Program. Ser. A (2015), pp. 1–52], and we also derive the first high probability iteration complexity result where the initial levelset is unbounded. 相似文献
994.
Structural equation modeling of office environment quality,sick building syndrome,and musculoskeletal complaints on aggregate satisfaction of office workers 下载免费PDF全文
This study aims to analyze the effects of office environment quality (OEQ), sick building syndrome (SBS), and musculoskeletal complaints on aggregate office satisfaction level using the structural equation. A questionnaire survey targeting 483 office workers of 18 public agencies was conducted and surveyed on workers’ characteristics (gender, age, work experience, work hours, and computer time of day), OEQ satisfaction level (temperature and humidity, lighting, noise, and air quality), SBS frequency (eye, noise, throat, skin, and headache), musculoskeletal complaints intensity (neck, shoulder, arm, wrist, waist, and leg), and aggregate office satisfaction level. As a result of the model using the structural equation, the level of OEQ on temperature and humidity, noise, and air quality directly affect the level of SBS frequency. Also, the OEQ level indirectly affects both musculoskeletal complaints’ intensity and aggregate office satisfaction level via the level of SBS frequency. Thus, providing pleasant office environments can be an effective measure to enhance office workers’ satisfaction, because workers’ levels for musculoskeletal complaints and aggregate office satisfaction depend on OEQ and SBS levels. 相似文献
995.
Jinhyeok Oh Suin Kim Sangyeop Lee Seongmin Jeong Seung Hwan Ko Joonbum Bae 《Advanced functional materials》2021,31(39):2007772
Virtual reality (VR) has been widely used for training, gaming, and entertainment, and the value of VR is continually increasing as a contact-free technology. For an immersive VR experience, measuring finger movements and providing appropriate feedback to the hand are as important as visual information, given the necessity of the hands for activities in daily life. Thus, a hand-worn VR device with motion sensors and haptic feedback is desirable. In this paper, a multimodal sensing and feedback glove is developed with soft, stretchable, lightweight, and compact sensor and heater sheets manufactured by direct ink writing (DIW) of liquid metal, eutectic gallium-indium (eGaIn). In the sensor sheet, ten sensors and three vibrators are embedded to measure finger movements and provide vibro-haptic feedback. The other heater sheet provides thermo-haptic sensation in accurate and rapid manner via model-based feedback control even under stretched conditions. The multimodal sensing and feedback glove allows users to feel the contact status and discriminate materials with different temperature. Performance of the proposed multimodal glove is verified under VR environments including touching and pushing two blocks of different materials and grabbing a heated metal ball submerged in hot water. 相似文献
996.
Hye-Seon Jeong Eunseo Kim Changwoo Nam Yoon Choi You-Jeong Lee David A. Weitz Hyomin Lee Chang-Hyung Choi 《Advanced functional materials》2021,31(18):2009553
A hydrogel microcapsule with an intermediate thin oil layer is presented to achieve smart release of a broad range of cargoes triggered via diverse stimuli. A microfluidic technique is used to produce triple emulsion droplets with a thin oil layer that separates the innermost aqueous phase from the hydrogel prepolymer phase, which transforms into a hydrogel shell via photopolymerization. The intermediate oil layer within the hydrogel microcapsule acts as an effective diffusion barrier, allowing encapsulation of various small cargoes within a porous hydrogel shell until a stimulus is applied to destabilize the oil layer. It is demonstrated that diverse stimuli including chemical dissolution, mechanical stress, and osmotic pressure can be utilized to release the encapsulated cargo on-demand. In addition, osmotic pressure and the hydrogel shell thickness can be independently tuned to control the onset time of release as well as the release behavior of multi-cargo encapsulated hydrogel microcapsule. The release can be either simultaneous or selective. 相似文献
997.
Ki-Tae Kim Hye-Jin Jin Wonjun Choi Yeonsu Jeong Hyung Gon Shin Yangjin Lee Kwanpyo Kim Seongil Im 《Advanced functional materials》2021,31(21):2010303
Gallium trioxide, β-Ga2O3, has been recently studied due to its promising semiconducting properties as active material in transistors or Schottky diodes. Transistors with β-Ga2O3 channels are mostly metal oxide field effect transistors (MOSFET), and they show very negative threshold voltages (Vth) in general. Metal semiconductor field effect transistors (MESFETs) with top gate are also reported with less negative Vth. Still, β-Ga2O3 MESFETs are only a few. Here, bottom gate architecture β-Ga2O3 MESFETs using transition metal dichalcogenide (TMD) NbS2 and TaS2 are reported. Due to the large work functions of those metallic TMDs, the MESFETs display minimum subthreshold swing of 61 mV dec−1, small Vth of −1.2 V, minimum OFF ID of ≈100 fA, and maximum ON/OFF current ratio of ≈108. Both β-Ga2O3 Schottky diodes with TaS2 and NbS2 display good junction stability even after 300 °C measurements in 10 mTorr vacuum. When the β-Ga2O3 MESFET with TaS2 gate is integrated as a switching FET into an organic light emitting diode (OLED) circuit, it demonstrates long-term leakage endurance performance, maintaining an OLED brightness higher than 58% of the initial intensity after 100 s passes since the ON-switching point, which is even superior to the performance of conventional a-IGZO MOSFET switch. 相似文献
998.
Xiaowu Tang G. Murali Hyungjin Lee Seongmin Park Seongeun Lee Sun Moo Oh Jihoon Lee Tae Yun Ko Chong Min Koo Yong Jin Jeong Tae Kyu An Insik In Se Hyun Kim 《Advanced functional materials》2021,31(29):2010897
MXenes are interesting 2D materials that have been considered as attractive frontier materials for potential applications in the fields of energy and electronic devices due to their excellent optoelectronic properties including metallic conductivity and high optical transparency. However, it is still challenging to achieve compatibility for the as-synthesized MXene nanosheets with simple solution-deposition and patterning processes because of their limited solubility in many solvents. Here, a promising strategy is developed for obtaining alcohol-dispersible MXene nanosheets suitable for all-printed electronics while enhancing their electrical conductivity. This strategy includes a trifluoroacetic acid treatment—applied in order to contribute to the modification of intercalants between the MXene nanosheets—and achieves long-term dispersion of the MXene in alcoholic media and balanced jetting conditions during the electrohydrodynamic printing process. Furthermore, the high conductivity levels of the treated MXenes allow their printed patterns to be applied as gate and source/drain electrodes in all-printed logic circuits, displaying good and robust operation in transistors, inverters, and NAND, and NOR logic gates. This study provides a promising approach for modifying MXene nanosheets with the purpose of achieving desirable properties suitable for large-area printing processes, suggesting the feasibility of using MXene in practical applications involving all-printed electronics. 相似文献
999.
Min Ju Kim Changhyeon Lee Eui Joong Shin Tae In Lee Seongho Kim Jaejoong Jeong Junhwan Choi Wan Sik Hwang Sung Gap Im Byung Jin Cho 《Advanced functional materials》2021,31(41):2103291
With the recent interest in data storage in flexible electronics, highly reliable charge trap-type organic-based non-volatile memory (CT-ONVM) has attracted much attention. CT-ONVM should have a wide memory window, good endurance, and long-term retention characteristics, as well as mechanical flexibility. This paper proposed CT-ONVM devices consisting of band-engineered organic–inorganic hybrid films synthesized via an initiated chemical vapor deposition process. The synthesized poly(1,3,5-trimethyl-1,3,5,-trivinyl cyclotrisiloxane) and Al hybrid films are used as a tunneling dielectric layer and a blocking dielectric layer, respectively. For the charge trapping layer, different Hf, Zr, and Ti hybrids are examined, and their memory performances are systematically compared. The best combination of hybrid dielectric stacks showed a wide memory window of 6.77 V, good endurance of up to 104 cycles, and charge retention of up to 71% after 108 s even under the 2% strained condition. The CT-ONVM device using the hybrid dielectric stacks outperforms other organic-based charge trap memory devices and is even comparable in performance to conventional inorganic-based poly-silicon/oxide/nitride/oxide/silicon structures devices. The CT-ONVM using hybrid dielectrics can overcome the inherent low reliability and process complexity limitations of organic electronics and expedite the realization of wearable organic electronics. 相似文献
1000.
Gunhyu Bae Yoo Sang Jeon Min Jun Ko Yuri Kim Seong-Beom Han Ramar Thangam Wonsik Kim Hee Joon Jung Sungkyu Lee Hyojun Choi Sunhong Min Hyunsik Hong Sangwoo Park Seong Yeol Kim Kapil D. Patel Na Li Jeong Eun Shin Bum Chul Park Hyeon Su Park Jun Hwan Moon Yu Jin Kim Uday Kumar Sukumar Jae-Jun Song Soo Young Kim Seung-Ho Yu Yun Chan Kang Steve Park Seung Min Han Dong-Hwee Kim Ki-Bum Lee Qiang Wei Liming Bian Ramasamy Paulmurugan Young Keun Kim Heemin Kang 《Advanced functional materials》2021,31(37):2103409
Developing materials with the capability of changing their innate features can help to unravel direct interactions between cells and ligand-displaying features. This study demonstrates the grafting of magnetic nanohelices displaying cell-adhesive Arg-Gly-Asp (RGD) ligand partly to a material surface. These enable nanoscale control of rapid winding (“W”) and unwinding (“UW”) of their nongrafted portion, such as directional changes in nanohelix unwinding (lower, middle, and upper directions) by changing the position of a permanent magnet while keeping the ligand-conjugated nanohelix surface area constant. The unwinding (“UW”) setting cytocompatibility facilitates direct integrin recruitment onto the ligand-conjugated nanohelix to mediate the development of paxillin adhesion assemblies of macrophages that stimulate M2 polarization using glass and silicon substrates for in vitro and in vivo settings, respectively, at a single cell level. Real time and in vivo imaging are demonstrated that nanohelices exhibit reversible unwinding, winding, and unwinding settings, which modulate time-resolved adhesion and polarization of macrophages. It is envisaged that this remote, reversible, and cytocompatible control can help to elucidate molecular-level cell–material interactions that modulate regenerative/anti-inflammatory immune responses to implants. 相似文献