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The hafnium oxide-based ferroelectric tunnel junction (FTJ) has been actively researched because of desirable advantages such as low power and CMOS compatibility to operate as a memristor.

This paper explores national strategies for emerging countries with ambitious policy targets for future offshore wind development. A scenario-based economic cost-benefit analysis of multiple approaches to the development of offshore wind projects is conducted based on (1) who takes the initiative on financing (public sector vs. private sector), (2) whether wind turbines are supplied locally or not, and (3) whether investment plans provide managerial flexibility to respond to changing circumstances or not (real options strategy vs. traditional investment decision-making). The analysis demonstrates that a real options strategy that allows flexibility regarding future uncertainties can significantly increase the economic value of a project regardless of the type of developer or dependence on foreign wind turbine technologies. The study concludes with a recommendation that late-mover countries focus on the combination of public-sector initiatives, a real options strategy, and the purchase of domestic turbines.

Motor learning relies on adjusting the performance of movements via error detection and correction. How motor learning proceeds via motor imagery, the imagination of movement, is not understood. Motor imagery-based learning is thought to rely on comparing the predicted effect of movement, resulting from the forward model, against its intended effect. Whether motor imagery-based learning uses the observed effect of movement, simulated in motor imagery, to make comparisons to the intended effect to permit error detection and correction, is an open question. To address this, transcranial magnetic stimulation was used to inhibit the left inferior parietal lobe (L_IPL) after each trial of a task requiring participants to reproduce complex trajectories via motor imagery. From past work, we speculated the L_IPL was a candidate for integrating simulated feedback about task performance (simulated observed effects), hypothesizing inhibition of the L_IPL would impair learning, suggesting simulated observed effects of movement are used in motor imagery-based learning. Participants received stimulation to the L_IPL or over the vertex of the head after each trial. Learning was defined as reduced error on a repeated trajectory in comparison to randomly generated trajectories. Regardless of group participants learned, a finding countering our hypothesis, suggesting (a) observed effects of movement are not simulated in motor imagery; (b) the L_IPL is not involved in integrating simulated observed effects of movement; or (c) the timing of the stimulation did not align with the speculated role of the L_IPL. Results encourage further research probing simulated feedback in motor imagery and its neural correlates. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Geometrically frustrated kagome materials reveal many novel states of matter ranging from quantum spin liquids to multiferroics. Herein, we study the compound CaFe3O(PO4)3, which has a quasi-two-dimensional lattice of Fe3+ ions with spin S = 5/2. Electrical and magnetic properties have been investigated on polycrystalline specimens of CaFe3O(PO4)3 using magnetization, pyroelectric, and magnetoelectric current measurements. The system undergoes a weak ferromagnetic-type ordering at TC1 ∼ 19.5 K, followed by another transition at TC2 ∼ 9 K. While no ferroelectric polarization (P) is observed at a zero magnetic field (H), the applied H induces P below TC2. At the temperature of 2.5 K, P starts to increase above H of 1 T, shows a maximum value at 3.15 T, and then decreases at higher H regions. The observed results suggest that CaFe3O(PO4)3 should be a magnetic-field-induced ferroelectric compound with frustrated magnetic couplings.

Supplementary Materials and Methods, Figures S1-S7, Table S1. Supplementary Materials and Methods. Porous hydrogel scaffold fabrication; 3D culture of primary human bone marrow stromal cells; In vitro invasion assay; In vitro proliferation assay. Supplementary Figure S1. In vitro PC-3 cell invasion and proliferation assays. Supplementary Figure S2. Human BMSC survival in vivo and marrow-like microenvironment formation in scaffolds 4 weeks after subdermal implantation in NSG mice. Supplementary Figure S3. Longitudinal bioluminescence monitoring of human tumor xenografts. Supplementary Figure S4. Histological analysis of PC-3 cells. Supplementary Figure S5. Ex vivo monitoring of DU-145 and MDA-231 #1833 cell engraftment in explanted scaffolds. Supplementary Figure S6. Metastasis development in DU-145 and MDA-231 #1833 xenograft models after scaffold transplantation. Supplementary Figure S7. Effect of IL-1Ra and IL-1b on PC-3 cell growth. Supplementary Table S1. Comprehensive list of genes interrogated by the Mouse Tumor Metastasis RT2 Profiler PCR Array.

Ethical management is not a choice for companies, but a necessity. This study, therefore, filled a need for further research into ethical management. We looked at the factors involved in a company’s employment of an ethical management system and relationships between factors to determine how the subordinate variable, the ethical management system, affects the performance of an enterprise.In specific, this study identified internal and external factors involved in ethical management systems in Korea’s domestic shipping and port logistics companies. We investigated the impact of these factors on organizational performance variables and each level of the ethical management system.According to empirical findings, only internal factors such as openness and internal integrity, and external factors such as normative and cognitive environments, had positive effects on the use of an ethical management system. On the other hand, transparency, which is an internal factor, and regulatory environment, which is an external factor, had no positive impact.

Venadaparib (VEN), a next-generation inhibitor of poly (ADP-ribose) polymerases, is under development for oral use in patients having cancers with deoxyribonucleic acid repair defects. The objective of this study was to develop and validate a sensitive and robust analytical method for quantifying VEN in a small volume of plasma samples from rats and dogs, and to assess the feasibility of the assay for application in pharmacokinetic/toxicokinetic studies. Plasma samples were subjected to deproteination, and an aliquot was injected into an LC–MS/MS system. VEN and imipramine were analyzed in the positive ion mode and quantified by monitoring the transition at m/z 407.2 → 70.0 for VEN and 281.2 → 86.1 for imipramine. The lower and upper limits of the assay were determined to be 1 and 1000 ng/mL, respectively, with acceptable linearity (r2 > 0.995). Validation parameters, such as accuracy, precision, dilution, recovery, matrix effect, and stability, were within acceptable ranges. This method was adequately applied to the characterization of pharmacokinetics of VEN in rats and dogs at the oral dose of 30 and 0.5 mg/kg, respectively. These findings suggest that the validated assay is applicable to the kinetic studies of VEN with a small volume of plasma samples from the animals.

Herein, we present a novel low-temperature polycrystalline silicon (LTPS) thin-film transistor (TFT) pixel circuit for a micro light-emitting diode ( $\mu $ LED) display based on pulse width modulation (PWM). By adopting PWM, we could achieve 10-bit gray levels of $\mu $ LED without wavelength shift, which is a challenge in the realization of $\mu $ LEDs. Furthermore, the proposed circuit compensated for the variation in threshold voltage ( ${V}_{{\text {TH}}}$ ) without an external sensing system. We simulated the error rate of the $\mu $ LED emission time of the proposed pixel circuit depending on the VTH change. We measured the wavelength shift of the $\mu $ LED using the fabricated circuit. This shift in PWM was smaller than that in pulse amplitude modulation (PAM). Consequently, the proposed pixel circuit could overcome screen distortions caused by color shifts of $\mu $ LED displays using PWM techniques.

Whereas the concept of platform government emerged a decade ago and virtual states are predicted beginning early 2000’s, supporting technologies and infrastructures are now being installed and implemented with highly integrative technologies such as cloud computing, bigdata analytics, mobile computing, social media, Internet of Things, and AI. This realization of platform governments leads us to rethink what have been predicted decades ago. Time has come for us to really open up real opportunities by facing realistic challenges for public management. The pressure for government innovations such as algorithmic bureaucracy and collaborative value creation are increasing. Attentions need to be paid with respect to how the managerial role and activities are being transformed, how the nature of work in government is fundamentally changed, and how the decision-making processes are re-institutionalized. Further research issues are discussed at the end of this viewpoint.

Wireless power transfer is a promising solution for wireless networks composed of Internet-of-Things (IoT) devices that may suffer from insufficient battery capacity. A wireless powered communication network (WPCN) is a framework to design energy-constrained networks such as IoT networks. In this article, we consider WPCNs consisting of a hybrid access point (H-AP) and energy harvesting users, all equipped with multiple antennas. A H-AP transfers energy to the users using energy beamforming in the downlink, and the users transmit information using the harvested energy in the uplink, where nonorthogonal multiple access (NOMA) transmission is employed. For the uplink NOMA transmission, users are grouped into multiple clusters by cluster-specific beamforming. In particular, signal alignment is exploited for the beamforming so that the channels of users in a cluster are aligned in the same direction. By signal alignment, the number of messages decoded by successive interference cancellation (SIC) is reduced, which can be effective at lowering the decoding complexity and SIC error propagation. Due to the difficulty of jointly optimizing cluster-specific beamforming and time/energy resources for sum-throughput maximization, we determine the beamforming relying on signal alignment first, and then the resources are optimized for given beamforming. To be more specific, we propose a novel iterative algorithm for cluster-specific beamforming design followed by the sum-throughput maximization algorithm. Numerical results show the sum-throughput performance of the proposed scheme and its robustness toward SIC error propagation compared to existing schemes.

NDF (No Defect Found) is a phenomenon in which defects have been found in the manufacturing, operation and use of a product or facility, but phenomenon of defects is not reproduced in the subsequent investigation system or the cause of the defects cannot be identified. Recently, with the development of the fourth industrial revolution, convergence of hardware and software technologies in various fields is spreading to products such as aircraft, home appliances, and mobile devices, and the number of parts is increasing due to functional convergence. The application of such convergence technologies and the increase in the number of parts are major factors that lead to an increase in NDF phenomena. NDF phenomena have a significant negative impact on cost, reliability, and reliability for both manufacturers, service providers and operators. On the other hand, due to the nature of NDF phenomena such as difficult and intermittent cause identification and ambiguity in judgment, it is common to underestimate the cost of NDF or fail to take appropriate countermeasures in corporate management. Therefore, in this paper, we propose a methodology for estimating NDF costs by the PAF model which is a quality cost analysis model and ABC (Activity Based Costing) technique. The methodology of this study suggests a detailed procedure and the concept to accurately estimate the NDF costs, using ABC analysis, accounting system information, and IT system data. In addition case studies have validated the methodology. We think this could be a valid methodology to refer to when estimating the cost of other parts. And, it is meaningful to provide important judgment information in the decision-making process based on quality management and ultimately reduce NDF costs by visualizing them separately by major variable factors.

This study assessed internet users’ attention to hospitality companies’ COVID-19 messages on social media. We used 657 Facebook and 754 Twitter messages initiated by eight of the world’s largest hotel chains between January and mid-June 2020 for the exploratory analysis. Under the situational crisis communication theory, the analysis reveals that hotels shared five types of COVID-19 ( Prevention, Reminding, Ingratiation, Victimage, and Updates) versus Non-COVID-19 messages. Descriptive analysis and a series of t test, analysis of variance, and post hoc analyses reveal that hotels did not share any COVID-19 information until March 2020. Moreover, COVID-19 messages only accounted for about 20% of all messages, among which hotels shared Ingratiation and Updates messages most often. COVID-19 messages received more reactions, comments, and shares/retweets than Non-COVID-19 messages on both Facebook and Twitter, indicating the attention paid to the COVID-19 messages posted on a business’ social media page, which can help businesses spread the information in their networks. Specifically, Prevention, Reminding (although underused), Ingratiation, Updates, and messages with photos and videos received more attention. Such findings extend the crisis communication literature and help businesses develop effective communication strategies to engage their stakeholders on social media during the pandemic.

Obesity-induced inflammation in adipose tissue (AT) promotes the development of metabolic dysregulations by increasing macrophage recruitment in the stromal vascular fraction (SVF). The activation of nuclear factor-κB (NF-κB) signaling in macrophages serves as a pivotal mediator of AT inflammatory responses by increasing the expression of proinflammatory genes in obesity. Given the purported anti-inflammatory effects of berry consumption in humans, we evaluated if anthocyanin-rich aronia berry extract (ARN) can prevent obesity-induced AT inflammation in vivo. We also examined whether ARN suppresses lipopolysaccharide (LPS)-induced NF-κB activation in RAW 264.7 macrophages and mouse bone marrow-derived macrophages (BMDMs). Male C57BL/6J mice were fed a low-fat diet, a high-fat (HF), and high-sucrose (HS) diet or HF/HS diet supplemented with 0.2% ARN (HF/HS + ARN) for 14 weeks. Compared to HF-/HS-fed mice, ARN supplementation tended to decrease fasting serum glucose (P = .07). Furthermore, ARN supplementation significantly inhibited the phosphorylation of NF-κB p65 in epididymal AT with a concomitant decrease in the expression of Cd11b and Tnfα mRNAs in epididymal SVF isolated, compared with those from HF-/HS-fed mice. Consistent with these in vivo findings, ARN treatment significantly decreased the phosphorylation of p65 in LPS-stimulated RAW 264.7 macrophages and BMDMs. Moreover, ARN suppressed LPS-induced mRNA expression of inflammation mediators (iNos, Cox-2, Tnfα, Mcp-1, and Il-6) and glycolysis markers (Glut1, G6pdh, and Hk1) in both cell types. Taken together, our in vivo and in vitro results suggest that ARN supplementation may attenuate obesity-induced AT inflammation by inhibiting NF-κB signaling and glycolytic pathway in macrophages.

Hyperspectral endoscopy has shown its potential to improve disease diagnosis in gastrointestinal tracts. Recent approaches in developing hyperspectral endoscopy are mainly focusing on enhancing image speed and quality of spectral information under a clinical environment, but there are many issues in obtaining consistent spectral information due to complicated imaging conditions, including imaging angle, non-uniform illumination, working distance, and low reflected signal. We quantitatively investigated the effect of imaging angle on the distortion of spectral information by exploiting a bifurcated fiber, spectrometer, and tissue-mimicking phantom. Spectral distortion becomes severe as increasing the angle of the imaging fiber or shortening camera exposure time for fast image acquisition. Moreover, spectral ranges from 450 to 550 nm are more susceptible to the angle-dependent spectral distortion than longer spectral ranges. Therefore, imaging angles close to normal and longer target spectral ranges with enough detector exposure time could minimize spectral distortion in hyperspectral endoscopy. These findings will help implement clinical HSI endoscopy for the robust and accurate measurement of spectral information from patients in vivo.

In this letter, we consider wireless powered communication networks (WPCNs) that consist of a hybrid access-point (H-AP) with a single antenna, an intelligent reflecting surface (IRS), and multiple users, each with a single antenna. In the downlink, users harvest energy from both an energy signal transmitted from the H-AP, and the reflected signal at the IRS. In the uplink, users transmit information using harvested energy, following non-orthogonal multiple access (NOMA). In particular, the signals from users and the reflected signals at the IRS are superposed and received at the H-AP. The sum-throughput for the considered network is maximized by jointly optimizing the transmit time, power, and phase shifts induced by the IRS. Numerical results show the sum-throughput enhancement by the IRS, and the impact of the IRS on the user fairness of the system.

This article considers a power allocation problem in energy harvesting downlink non-orthogonal multiple access (NOMA) systems in which a transmitter sends desired messages to their respective receivers by using harvested energy. To tackle this problem, we make use of a reinforcement learning approach based on a shallow neural network structure. We prove that the optimal power allocation policy and the optimal action-value function depend monotonically on some of their input variables and the shallow neural network structure is designed based on properties revealed in the proof. Different from inefficient deep learning methods that tend to require tremendous computational resources, this structure is capable of fully capturing the characteristics of the desired function with a single hidden layer. The optimized structure also allows learning agents to be robust and highly reliable in learning about randomly occurring data. Furthermore, we provide comprehensive experimental results in harsh environments where various arbitrary factors are assumed in order to demonstrate the robustness of the proposed learning approach compared with deep neural networks without proper grounds. It is also shown that the proposed learning process converges to a policy that outperforms existing power allocation algorithms.

The smart mobile Internet-of-things (IoT) network lays the foundation of the fourth industrial revolution, the era of hyperconnectivity, hyperintelligence, and hyperconvergence. As this revolution gains momentum, the security of smart mobile IoT networks becomes an essential research topic. This study aimed to provide comprehensive insights on IoT security. To this end, we conducted a systematic mapping study of the literature to identify evolving trends in IoT security and determine research subjects. We reviewed the literature from January 2009 to August 2020 to identify influential researchers and trends of keywords. We additionally performed structural topic modeling to identify current research topics and the most promising ones via topic trend estimation. We synthesized and interpreted the results of the systematic mapping study to devise future research directions. The results obtained from this study are useful to understand current trends in IoT security and provide insights into research and development of IoT security.

Recently, coded computation has been used to reduce the completion time in distributed computing by mitigating straggler effects with erasure codes. As a variation of coded computation, fully private coded matrix multiplication (FPCMM) has been proposed to preserve a master’s privacy in a scenario where the master wants to obtain a matrix multiplication result from the libraries which are shared at the workers, while concealing both of the two indices of the desired matrices from each worker. In this letter, we propose a new FPCMM scheme to keep a master’s privacy from up to $T$ colluding workers. Furthermore, we compare the performance of our scheme with those of the existing private coded matrix multiplication schemes for non-colluding workers and for concealing the index of a single desired matrix.