Secret Key Generation from Correlated Sources and Secure Link

In this paper, we study the problem of secret key generation from both correlated sources and a secure channel. We obtain the optimal secret key rate in this problem and show that the optimal scheme is to conduct secret key generation and key distribution jointly, where every bit in the secret channel will yield more than one bit of secret key rate. This joint scheme is better than the separation-based scheme, where the secure channel is used for key distribution, and as a result, every bit in the secure channel can only provide one bit of secret key rate.Comment: 5 pages, 1 figur

Junction-Less Monolayer MoS2 FETs

This paper introduces monolayer molybdenum disulfide (MoS2) based junction-less (JL) field-effect transistor (FET) and evaluates its performance at the smallest foreseeable (5.9 nm) transistor channel length as per the International Technology Roadmap for Semiconductors (ITRS), by employing rigorous quantum transport simulations. By comparing with MoS2 based conventional FETs, it is found that the JL structure naturally lends MoS2 FETs with superior device electrostatics, and higher ON-current for both high-performance and low-standby-power applications, especially at high impurity doping densities. Along with the advantages of the MoS2 JL-FETs, the effects of impurity scattering induced carrier mobility degradation of JL-FETs is also highlighted as a key technological issue to be addressed for exploiting their unique features

Light dark matter in NMSSM and implication on Higgs phenomenology

For the experimental search of neutralino dark matter, it is important to know its allowed mass and scattering cross section with the nucleon. In order to figure out how light a neutralino dark matter can be predicted in low energy supersymmetry, we scan over the parameter space of the NMSSM (next-to-minimal supersymmetric model), assuming all the relevant soft mass parameters to be below TeV scale. We find that in the parameter space allowed by current experiments the neutralino dark matter can be as light as a few GeV and its scattering rate off the nucleon can reach the sensitivity of XENON100 and CoGeNT. As a result, a sizable parameter space is excluded by the current XENON100 and CoGeNT data (the plausible CoGeNT dark matter signal can also be explained). The future 6000 kg-days exposure of XENON100 will further explore (but cannot completely cover) the remained parameter space. Moreover, we find that in such a light dark matter scenario a light CP-even or CP-odd Higgs boson must be present to satisfy the measured dark matter relic density. Consequently, the SM-like Higgs boson $h_{SM}$ may decay predominantly into a pair of light Higgs bosons or a pair of neutralinos so that the conventional decays like $h_{SM} -> \gamma \gamma$ is much suppressed.Comment: Version in PLB (discussions added

The influence of companion factors on soundscape evaluations in urban public spaces

'Soundscape' refers to how individuals or groups of people perceive sounds. This study focuses on whether and to what extent companion factors, compared with other demographic factors, influence the various aspects of soundscape evaluation. Two kinds of companion factors are studied here: one is companion status, the other is the social relationship intensity between companions. Based on a questionnaire and statistical analysis, both companion factors are found to influence evaluations of socially interactive sounds- sound made by human activity. People accompanied are more likely to notice speaking and children sound and prefer safe and social sounds. People involved in closer social relationships tend to notice children's sounds more and prefer human sound types and social sound. Other factors may offset the influence of companion factors, however. Site factors interfere with accompanied people's tendencies to prefer safe sounds and notice children's sounds, and participants’ ages interfere with their tendencies to notice speaking sound. The results of this study suggest that human activity sounds can contribute to social sound among companions, whereas solo people may prefer more privacy and quietness. This study emphasizes companion factors in soundscape evaluations and suggests future soundscape design to satisfy people with different companions

A Perceptual Structure of Soundscapes in Urban Public Spaces Using Semantic Coding Based on the Grounded Theory

The definition of 'soundscape' emphasises the perceptual construct of sounds; thus, the mechanism of sound perceptions becomes vital for soundscape evaluations. Using a qualitative approach, this study explored the aspects and processes of sound perceptions and built a perceptual soundscape structure from the insight of sociology. The interview was conducted between January and March 2018, in four urban public spaces. Data reached saturation after 23 participants were interviewed based on the grounded theory approach. Four perceptual aspects of sounds were identified from the semantic coding analysis: sound classification, sound features, psychological reactions, and soundscape preferences. These aspects form a three-level process of perceiving soundscapes: sound classifications, sound appraisals (including sound features and psychological reactions), and finally, judgment (soundscape preferences). Overall, four aspects categorised into three levels of perception make up the soundscape structure. Soundscape preferences are at the most profound level of perception and are informed by the previous three aspects. Soundscape preferences are expressed through descriptive words and narrative 'image'. The 'image' reflects people participating in different activities according to their social background. Social relationships influence soundscape preferences through people's sound requirements for various activities. The perceptual structure of soundscapes may provide guidance for future soundscape research and soundscape questionnaire design

Social relationships and patterns of use in urban public spaces in China and the United Kingdom

Public spaces are social places that enhance social life and foster social interactions. However, there is a lack of analysis of the patterns of use by people in various types of social relationships. Observational data on four public spaces in Suzhou, China, and Sheffield, UK, assessed users' personal characteristics, activities and spatial occupancies in public spaces. Site factors were not related to personal characteristics, but age and group size were culturally different. Activities and spatial occupancies differed between unaccompanied and accompanied users. Compared to single users, users in groups tended to participate in multiple activities at once, and their activities included more interactions. Single users' spatial distributions conformed to the edge effect, but users in groups were evenly distributed in the spaces. Three types of social relationships were defined: Intimate Pair, Intimate Group and Social Group. Intimate Pairs were most likely to use mobile phones and use private spaces, Intimate Groups were most likely to be talking and sitting and to use park amenities, and Social Groups were most likely to be playing games and relaxing in spacious open areas. Regarding spatial occupancy, Intimate Pairs and Social Groups were most likely to use the middle and peripheral regions, and the Intimate Groups tended to be evenly distributed in the spaces. The results of this study stress the importance of designing public spaces for the types of users expected to use the spaces and to consider various types of social relationship groups

Three Dimensional Superconductivity in FeSe with Tczero Up to 10.9 K Induced by Internal Strain

Polycrystalline sample FeSe was synthesized by a self-flux solution method which shows a zero resistance temperature up to 10.9 K and a Tconset (90% \rhon, \rhon: normal state resistivity) up to 13.3 K. The decrease of superconducting transition temperature by heat treatment indicates that internal crystallographic strain which plays the same effect as external pressure is the origin of its high Tc. The fluctuation conductivity was studied which could be well described by 3D Aslamazov-Larkin (AL) power law. The estimated value of coherence length \xic=9.2 \AA is larger than the distance between conducting layers (~6.0 \AA), indicating the three-dimensional nature of superconductivity in this compound.Comment: 5 figure

Hypoglycemic, hypolipidemic and antioxidant effects of iridoid glycosides extracted from: Corni fructus: Possible involvement of the PI3K-Akt/PKB signaling pathway

Iridoid glycosides (CIG) are the major component of Corni fructus. In this work, we researched the antioxidative, hypoglycemic and lowering blood lipids effects of CIG on diabetic mice induced by a high-fat diet (HFD) and streptozotocin (STZ). Furthermore, to investigate the molecular mechanism of action, the phosphorylation and protein expression of phosphoinositide 3-kinase (PI3K) and its downstream proteins, such as insulin receptor (INSR), protein kinase B (Akt/PKB) and glucose transporter 4 (GLUT4) have been detected. The results showed that CIG significantly improved oral glucose tolerance in diabetic mice. Biochemical indices also revealed that CIG had a positive effect on lipid metabolism and oxidative stress. In addition, CIG can significantly enhance the expression level of the PI3K-Akt/PKB pathway related proteins in skeletal muscle, which is the key pathway of insulin metabolism. These findings show that CIG can improve the hyperglycemia and hyperlipidemia of HFD-STZ-induced diabetic mice through the PI3K-Akt/PKB signaling pathway, and CIG might be a potential medicine or functional food for type 2 diabetes mellitus remedies. © 2018 The Royal Society of Chemistry