Air transparent soundproof window

A soundproof window or wall which is transparent to airflow is presented. The design is based on two wave theories of diffraction and acoustic metamaterials. It consists of a three-dimensional array of strong diffraction-type resonators with many holes centered at each individual resonator. The acoustic performance levels of two soundproof windows with air holes of $20mm$ and $50mm$ diameters were measured. Sound waves of 80dB in the frequency range of $400 - 5,000Hz$ were applied to the windows. It was observed that the sound level was reduced by about $30 - 35$dB in the above frequency range with the $20mm$ window and by about $20 - 35$dB in the frequency range of $700 - 2,200Hz$ with the $50mm$ window. It is an extraordinary acoustic anti-transmission. The geometric factors which produced the effective negative modulus were obtained.Comment: 4 pages, 6 figures, 1 tabl

A comparative study of anti-slavery in 19th century Middle East and North Africa: the cases of the Egyptian Khedivate and the Husaynid Beylik of Tunis

In the nineteenth century, the polities in the Middle East and North Africa encountered the British pressure to abolish the slave trade and slavery. While the Khedivate of Egypt and the Husaynid Beylik of Tunis faced the same pressure, the internal causes of them such as a diplomatic motive also led them to adopt anti-slavery policies. However, despite the similar motivations and conditions, their practical measures against the slave trade and slavery showed apparent differences. Saʿid (r. 1854-1863) and Ismaʿil (1863-1879) of the Egyptian Khedivate took many measures against slavery and the slave trade, but their orders or decrees lacked detailed plans before the ultimate termination of the slave trade was announced in 1877, as a result of the Anglo-Egyptian convention. That convention was arranged only two years before the abdication of Ismaʿil and the convention did not specify the full abolition of slavery itself. As for the anti-slavery process of the Tunisian Beylik, Ahmad Bey (r. 1837-1855) took measures against slavery at a rapid pace. He prohibited the slave trade in 1841 and abolished slavery itself in 1846. The immediate and complete liberation of all slaves in 1846 was not attempted in the Khedivate of Egypt before it became a protectorate of the British Empire. This thesis attempts to find the major factors which influenced their different measures. For this purpose, three major differences between two polities in the scale of the slave trade, the presence of organized slave traders, and the government’s demand for slaves are compared. A comparison of the anti-slavery policies in two states that otherwise have multiple similar conditions will suggest the reasons for different paces and procedures of state-led anti-slavery efforts that can be applied to other polities. This comparison also may reveal to some extent how a state project during this period could be influenced by other state projects, their specific characteristics, and the interest groups related to those projects

Worst-case User Analysis in Poisson Voronoi Cells

In this letter, we focus on the performance of a worst-case mobile user (MU) in the downlink cellular network. We derive the coverage probability and the spectral efficiency of the worst-case MU using stochastic geometry. Through analytical and numerical results, we draw out interesting insights that the coverage probability and the spectral efficiency of the worst-case MU decrease down to 23% and 19% of those of a typical MU, respectively. By applying a coordinated scheduling (CS) scheme, we also investigate how much the performance of the worst-case MU is improved.Comment: Accepted, IEEE Communications Letter

Diboson Excesses Demystified in Effective Field Theory Approach

We study the collider implication of a neutral resonance which decays to several diboson final states such as $W^+W^-$, $ZZ$, and $Z\gamma$ via a minimal set of effective operators. We consider both CP-even and CP-odd bosonic states with spin 0, 1, or 2. The production cross sections for the bosonic resonance states are obtained with the effective operators involving gluons (and quarks), and the branching fractions are obtained with the operators responsible for the interactions with electroweak gauge bosons. We demonstrate that each scenario allows for a broad parameter space which could accommodate the recently-reported intriguing excesses in the ATLAS diboson final states, and discuss how the CP states and spin information of the resonance can be extracted at the LHC run II.Comment: 22 pages, 6 figures, main text slightly modified with results unchange

Rampant exchange of the structure and function of extramembrane domains between membrane and water soluble proteins.

Of the membrane proteins of known structure, we found that a remarkable 67% of the water soluble domains are structurally similar to water soluble proteins of known structure. Moreover, 41% of known water soluble protein structures share a domain with an already known membrane protein structure. We also found that functional residues are frequently conserved between extramembrane domains of membrane and soluble proteins that share structural similarity. These results suggest membrane and soluble proteins readily exchange domains and their attendant functionalities. The exchanges between membrane and soluble proteins are particularly frequent in eukaryotes, indicating that this is an important mechanism for increasing functional complexity. The high level of structural overlap between the two classes of proteins provides an opportunity to employ the extensive information on soluble proteins to illuminate membrane protein structure and function, for which much less is known. To this end, we employed structure guided sequence alignment to elucidate the functions of membrane proteins in the human genome. Our results bridge the gap of fold space between membrane and water soluble proteins and provide a resource for the prediction of membrane protein function. A database of predicted structural and functional relationships for proteins in the human genome is provided at sbi.postech.ac.kr/emdmp

Problem behaviours of kindergartners: The affects of children’s cognitive ability, creativity, and self-esteem

This study investigated the affects of cognitive ability, creativity, and self-esteem on kindergartners’ problem behaviour. Participants were 203 children (mean age = 65.8 months) attending kindergartens in Korea. Data collection used the Korean version of Child Behaviour Checklist, the Kaufman Assessment Battery for Children, the Torrance Test of Creative Thinking, and the Children's Sense of Self-Esteem Inventory. Pearson’s correlations and stepwise multiple regression analysis were used to analyse the data. There were four primary outcomes. First, there were negative correlations between children’s problem behaviour (internalising and externalising problems) and cognitive ability. Second, there was a negative correlation between internalising problems and fluency in creativity. No correlation was found between children’s externalising problems and creativity. Third, there were negative correlations between children’s problem behaviour (internalising and externalising problems) and self-esteem. Fourth, sequential processing, emotional competence, and fluency were revealed to be predictors of children’s internalising problems. Social competency and sequential processing were found to be predictors of children’s externalising problems.Keywords: cognitive ability; creativity; externalising problems; internalising problems; problem behaviour; self-estee

A study on the change in the characteristics of the gait of elderly people when somatosensory stimulation was applied to their ankle joint

The gait is the most complicated, habitual, and involuntary activity of humans and is a result of the cooperation of the central and peripheral nervous systems that harmoniously mobilize the sensory receptors, nervous system, and muscles. A sensory signal binds to a somatosensory system proprioceptor to obtain information on posture. This study was designed to analyze the change in the characteristics of a gait when stimulation is applied in the somatosensory system that controls the balance of the body. A result of the GRF obtained from the force plate and gyroscope signals from the sensor attached on ankle joint were obtained to compare the change before and after the somatosensory stimulation. The result of this study proved a potential of somatosensory stimulation in improving balance, which could be used in studies on the balance of positions and gait improvement