Multiple Transactions Model: A Panel Data Approach to Estimate Housing Market Indices

In this paper, a multiple transactions model with a panel data approach is used to estimate housing market indices. The multiple transactions model keeps the same features of the repeat transactions index model (i.e., tracking the price appreciation of same houses). However, the multiple transactions model overcomes the shortcomings of the repeat transactions model by avoiding the correlated error terms. The indicative empirical analysis on a small sample of actual house transaction data demonstrates that the proposed multiple transactions model is superior to the repeat transactions model in terms of index variance, robustness of estimate, index revision volatility, and out-of-sample prediction of individual house prices.

Anyon Wave Function for the Fractional Quantum Hall Effect

An anyon wave function (characterized by the statistical factor $n$) projected onto the lowest Landau level is derived for the fractional quantum Hall effect states at filling factor $\nu = n/(2pn+1)$ ($p$ and $n$ are integers). We study the properties of the anyon wave function by using detailed Monte Carlo simulations in disk geometry and show that the anyon ground-state energy is a lower bound to the composite fermion one.Comment: Reference adde

Machine Learning for Soft Robot Sensing and Control: A Tutorial Study

Developing feedback controllers for robots with embedded sensors is challenging and typically requires expert knowledge. As machine learning (ML) advances, the development of learning-based controllers has become more and more accessible, even to non-experts. This work presents the development of a tutorial to educate non-roboticists about ML-based sensing and control in cyber-physical systems using a soft robotic device. We demonstrated this by creating a recurrent neural network-based closed-loop force controller for a soft finger with embedded soft sensors. Our hypothesis is validated in a 2.5-hour workshop session for students with no prior knowledge of robot control. This work serves as a tutorial for participants aiming to experience and perform a general benchmark for soft robot control tasks, with little or even no expertise in robotics

Rapidly variable Fe Kα\alpha line in NGC 4051

We present a detailed analysis on the variability of the Fe K emission line in NGC 4051 using ASCA data. Through simple Gaussian line fits, we find not only obvious Fe K line variability with no significant difference in the X-ray continuum flux between two ASCA observations which were separated by $\sim$ 440 days, but also rapid variability of Fe K line on time scales $\sim 10^4$ s within the second observation. During the second observation, the line is strong (EW = 733$^{+206}_{-219}$ eV) and broad ($\sigma = 0.96^{+0.49}_{-0.35}$ keV) when the source is brightest, and become weaker (EW = 165$^{+87}_{-86}$ eV) and narrower ($\sigma<0.09$ keV) whilst the source is weakest. The equivalent width of Fe K line correlates positively with the continuum flux, which shows an opposite trend with another Seyfert 1 galaxy MCG --6-30-15.Comment: 12 pages with 5 figures, to appear in ApJ Vol. 516, L6

Traumatic Brain Injury in the Elderly: Is it as Bad as we Think?

Traumatic brain injury in elderly patients is a neglected global disease burden. The main cause is fall, followed by motor vehicle accidents. This review article summarizes different aspects of geriatric traumatic brain injury, including epidemiology, pathology, and effects of comorbidities and pre-injury medications such as antiplatelets and anticoagulants. Functional outcome with or without surgical intervention, cognitive outcome, and psychiatric complications are discussed. Animal models are also reviewed in attempt to explain the relationship of aging and outcome, together with advances in stem cell research. Though elderly people in general did fare worse after traumatic brain injury, certain “younger elderly” people, aged 65–75 years, could have a comparable outcome to younger adults after minor to moderate head injury

The charged-hadron/pion ratio at the Relativistic Heavy Ion Collider

The hadron/pion ratio is calculated in 200 GeV AuAu collisions at midrapidity, applying pQCD and non-universal transverse-momentum broadening. Arguments are presented for such non-universality, and the idea is implemented in a model, which explains the enhancement of the hadron/pion ratio in central AuAu collisions. The model also describes the qualitative difference between the recently-measured dAu nuclear enhancement factors for pions and charged hadrons.Comment: 4 pages, 3 figure

Intrinsic response time of graphene photodetectors

Graphene-based photodetectors are promising new devices for high-speed optoelectronic applications. However, despite recent efforts, it is not clear what determines the ultimate speed limit of these devices. Here, we present measurements of the intrinsic response time of metal-graphene-metal photodetectors with monolayer graphene using an optical correlation technique with ultrashort laser pulses. We obtain a response time of 2.1 ps that is mainly given by the short lifetime of the photogenerated carriers. This time translates into a bandwidth of ~262 GHz. Moreover, we investigate the dependence of the response time on gate voltage and illumination laser power

Nuclear Effects on Heavy Boson Production at RHIC and LHC

We predict W and Z transverse momentum distributions from proton-proton and nuclear collisions at RHIC and LHC. A resummation formalism with power corrections to the renormalization group equations is used. The dependence of the resummed QCD results on the non-perturbative input is very weak for the systems considered. Shadowing effects are discussed and found to be unimportant at RHIC, but important for LHC. We study the enhancement of power corrections due to multiple scattering in nuclear collisions and numerically illustrate the weak effects of the dependence on the nuclear mass.Comment: 21 pages, 11 figure

Photo-Thermoelectric Effect at a Graphene Interface Junction

We investigate the optoelectronic response of a graphene interface junction, formed with bilayer and single-layer graphene, by photocurrent (PC) microscopy. We measure the polarity and amplitude of the PC while varying the Fermi level by tuning a gate voltage. These measurements show that the generation of PC is by a photo-thermoelectric effect. The PC displays a factor of ~10 increase at the cryogenic temperature as compared to room temperature. Assuming the thermoelectric power has a linear dependence on the temperature, the inferred graphene thermal conductivity from temperature dependent measurements has a T^{1.5} dependence below ~100 K, which agrees with recent theoretical predictions