391 research outputs found
Investing in Real Estate: Mortgage Financing Practices and Optimal Holding Period
Real estate investments are typically characterized by high degrees of leverage and long-loan tenures. In perfect capital markets, leverage has no impact on the investment decision apart from tax considerations. However, the mortgage financing market is imperfect in many countries. In the presence of market imperfections, an optimal holding period exists for real property investments. We provide a simple rule to calculate the optimal holding period to compare the required rate of return with the leveraged rate of return on equity.
Investing in Real Estate : Mortgage Financing Practices and Optimal Holding Period
Real estate investments are typically characterized by high degrees of leverage and long loan tenures. In perfect capital markets, leverage has no impact on the investment decision apart from tax considerations. However, the mortgage financing market is imperfect in many countries. In the presence of market imperfections, an optimal holding period exists for real property investments. We provide a simple rule to calculate the optimal holding period is to compare the required rate of return with the leveraged rate of return on equity.mortgage financing, real estate, financial leverage, optimal holding period
Mosquitoes of Kudat: species composition and their medical importance(diptera: culicidae)
A survey of mosquito fauna was done to determine the mosquito population and species composition in Kudat. Outdoor human landing catches (HLC) were done from April to June 2015. A total of 4,350 mosquitoes, representing eight genera and 37 species were collected. These include Aedes (Stegomyia), Aedimorphus, Anopheles, Armigeres, Culex, Mansonia, Phagomyia and Uranotaenia. Medical important species are specially noted and discussed. Armigeres (52.7%) was the most abundant, followed by Culex (31.9%), Aedes (9.4%), and Anopheles (4.3%). Armigeres kesseli and Ar. subabaltus were the two most common species. Armigeres annulipalpi and Phagomyia prominens are new records of Sabah
Comparative Study of TCM, TTCM, BICM and BICM-ID Schemes
Coded modulation is a bandwidth efficient scheme that combines the functions of coding and modulation. In this contribution, a comparative study of Trellis Coded Modulation (TCM), Turbo Trellis Coded Modulation (TTCM), Bit-Interleaved Coded Modulation (BICM) and Iterative Decoding assisted BICM (BICM-ID) schemes over Gaussian and uncorrelated narrowband Rayleigh fading channels is presented in the context of 8-level Phase Shift Keying (8PSK), 16-level Quadrature Amplitude Modulation (16QAM) and 64QAM. We comparatively study the associated decoding complexity, block length and bandwidth efficiency. It is shown that TTCM constitutes the best compromise scheme, followed by BICM-ID
Numerical assessment of directional energy performance for 3D printed midsole structures
Energy can be represented in the form of deformation obtained by the applied force. Energy transfer is defined in physics as the energy is moved from one place to another. To make the energy transfer functional, energy should be moved into the right direction. If it is possible to make a better use of the energy in the right direction, the energy efficiency of the structure can be enhanced. This idea leads to the concept of directional energy transfer (DET), which refers to transferring energy from one direction to a specific direction. With the recent development of additive manufacturing and topology optimization, complex structures can be applied to various applications to enhance performances, like a wheel and shoe midsole. While many works are related to structural strength, there is limited research in optimization for energy performance. In this study, a theoretical approach is proposed to measure the directional energy performance of a structure, which can be used to measure the net energy in an intended direction. The purpose is to understand the energy behavior of a structure and to measure if a structure is able to increase energy in the desired direction
Calorimetric and Rheological Measurements of Three Commercial Thermosetting Prepreg Epoxies
The cure kinetics of three different thermosetting resins are investigated using differential scanning calorimetry and oscillatory shear rheometry. For the latter, two different types of plates are used, smooth plates and grooved plates; the latter are used to improve sample–plate contact. In addition, oscillatory compression rheology is used; however, machine compliance prevents accurate measurements at high conversions. A fractional conversion is defined based on the maximum storage modulus achieved at a given temperature, and is compared to the fractional conversion calculated from enthalpy measurements. As expected, the rates of reaction derived from these fractional conversions are very different for calorimetry and rheometry. However, the rates of reaction using the two types of plates are identical, although the grooved plates give much more reproducible storage moduli. A number of previously used mathematical expressions are employed to fit the calorimetric and rheological data, and the activation energies calculated from these fits are compared.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline
Correlated two-electron transport: a principle for a novel charge pump
By considering a correlated two-electron transport process (TET) and using a
diagrammatic analysis within the Keldysh nonequilibrium Green's function
formalism, we discuss a novel charge pump by which carriers are pumped from a
contact with low chemical potential to another contact with a higher potential.
The TET process involves two correlated incident electrons scattering and
exchanging energy with each other. The process can significantly affect charge
current density and it involves high empty states and/or low filled states of
the Fermi liquid of the leads.Comment: 4 pages, 4 figures, revte
Transport in Coupled Quantum Dots: Kondo Effect Versus Anti-Ferromagnetic Correlation
The interplay between the Kondo effect and the inter-dot magnetic interaction
in a coupled-dot system is studied. An exact result for the transport
properties at zero temperature is obtained by diagonalizing a cluster, composed
by the double-dot and its vicinity, which is connected to leads. It is shown
that the system goes continuously from the Kondo regime to an
anti-ferromagnetic state as the inter-dot interaction is increased. The
conductance, the charge at the dots and the spin-spin correlation are obtained
as a function of the gate potential.Comment: 4 pages, 3 postscript figures. Submitted to PR
Low temperature transport in AC-driven Quantum Dots in the Kondo regime
We present a fully nonequilibrium calculation of the low temperature
transport properties of a quantum dot in the Kondo regime when an AC potential
is applied to the gate voltage. We solve a time dependent Anderson model with
finite on-site Coulomb interaction. The interaction self-energy is calculated
up to second order in perturbation theory in the on-site interaction, in the
context of the Keldysh non-equilibrium technique, and the effect of the AC
voltage is taken into account exactly for all ranges of AC frequencies and AC
intensities. The obtained linear conductance and time-averaged density of
states of the quantum dot evolve in a non trivial way as a function of the AC
frequency and AC intensity of the harmonic modulation.Comment: 30 pages,7 figure
Gait Retraining for the Reduction of Injury Occurrence in Novice Distance Runners: 1-Year Follow-up of a Randomized Controlled Trial
Background:
The increasing popularity of distance running has been accompanied by an increase in running-related injuries, such that up to 85% of novice runners incur an injury in a given year. Previous studies have used a gait retraining program to successfully lower impact loading, which has been associated with many running ailments. However, softer footfalls may not necessarily prevent running injury.
Purpose:
To examine vertical loading rates before and after a gait retraining program and assess the effectiveness of the program in reducing the occurrence of running-related injury across a 12-month observation period.
Study Design:
Randomized controlled trial; Level of evidence, 1.
Methods:
A total of 320 novice runners from the local running club completed this study. All the participants underwent a baseline running biomechanics evaluation on an instrumented treadmill with their usual running shoes at 8 and 12 km/h. Participants were then randomly assigned to either the gait retraining group or the control group. In the gait retraining group (n = 166), participants received 2 weeks of gait retraining with real-time visual feedback. In the control group (n = 154), participants received treadmill running exercise but without visual feedback on their performance. The training time was identical between the 2 groups. Participants’ running mechanics were reassessed after the training, and their 12-month posttraining injury profiles were tracked by use of an online surveillance platform.
Results:
A significant reduction was found in the vertical loading rates at both testing speeds in the gait retraining group (P 0.99), whereas the loading rates were either similar or slightly increased in the control group after training (P = .001 to 0.461, Cohen’s d = 0.03 to −0.14). At 12-month follow-up, the occurrence of running-related musculoskeletal injury was 16% and 38% in the gait retraining and control groups, respectively. The hazard ratio between gait retraining and control groups was 0.38 (95% CI, 0.25-0.59), indicating a 62% lower injury risk in gait-retrained runners compared with controls.
Conclusion:
A 2-week gait retraining program is effective in lowering impact loading in novice runners. More important, the occurrence of injury is 62% lower after 2 weeks of running gait modification.
Registration:
HKUCTR-1996 (University of Hong Kong Clinical Trials Registry)
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