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Traffic volume is a parameter used to quantify demand in transportation studies, and it is commonly collected by using on-road (fixed) sensors such as inductive loops, cameras, etc. The installation of fixed sensors to cover all roads is neither practical nor economically feasible; therefore, they are only installed on a subset of links. Cellular phone tracking has been an emerging topic developed and investigated during the last few years to extract traffic information. Cellular systems provide alternative methods to detect phones in motion without the cost and coverage limitations associated with those infrastructure-based solutions. Utilizing existing cellular systems to capture traffic volume has a major advantage compared with other solutions, since it avoids new and expensive hardware installations of sensors, with a large number of cellular phones acting as probes. This paper proposes a set of models for inferring the number of vehicles moving from one cell to another by means of anonymous call data of phones. The models contain, in their functional form, terms related to the users' calling behavior and other characteristics of the phenomenon such as hourly intensity in calls and vehicles. A set of intercell boundaries with different traffic background and characteristics were selected for the field test. The experiment results show that reasonable estimates are achieved by comparison with volume measurements collected by detectors located in the same study area. The motion of phones while being involved in calls can be used as an easily accessible, fast, and low-cost alternative to deriving volume data on intercell boundaries.

Background: The aim of this study is to confirm whether the absolute and relative lengths of the first metatarso-digital segment is greater than normal in incipient hallux limitus deformity. Methods: In a sample of 144 dorsoplantar radiographs under weightbearing conditions (94 of normal feet and 50 of feet with a slightly stiff hallux), measurements were made of the relative first metatarsal protrusion, the length and width of the first metatarsal and of the proximal phalanx of the hallux, the length of the distal phalanx of the hallux, and the total length of the hallux. Results: There were significant differences between the two types of feet in the relative first metatarsal protrusion, the width of the first metatarsal, the length and width of the proximal phalanx of the hallux, the length of the distal phalanx, and the total length of the hallux. Conclusion: The size of the first metatarso-digital segment could be implicated in the development of hallux limitus deformity. (J Am Podiatr Med Assoc 97(6): 460–468, 2007)

Two procedures are presented for obtaining the analytical expression for the efficiency of any planetary gear train. The first employs the speed and torque equations and the concept of virtual gear teeth ratios. The second is based on an relationship between the gearing power and the speed ratio. This relationship, which is satisfied by any spur gear train, allows one to obtain the efficiency expression in a surprisingly simple manner. Two proofs of that relationship are presented.

Technical and economic investigations of automated highway systems (AHS) are addressed. It has generally been accepted that such systems show potential to alleviate urban traffic congestion, so most of the AHS research has been focused instead on technical design and implementation issues. It is demonstrated that, despite making a number of assumptions that are favorable to AHS, the actual viable implementation opportunities for AHS are scarce, and that most existing congested urban areas can be disqualified on the basis of at least one criterion developed herein. Technical investigations are described, including realistic estimates of AHS capacity, interfacing with the local street system, and storage issues. Discussion then turns to identifying criteria to help establish the types of urban areas that might be likely candidates for AHS technology. These criteria relate to the nature of the surrounding infrastructure and the traffic demands placed on it, as well as the economic realities of AHS implementation. Certain “boutique” locations where AHS might be beneficial are identified, but it is uncertain whether enough benefit could be realized to make AHS palatable to the general public. AHS technology is not dismissed, but the simple analyses contained herein should warn that much more research into these areas is required before fully informed decision making about the future of AHS technologies can be accomplished.

The study of four-bar linkages to trace a desired path is an important part of teaching in mechanical design. When the number of precision points exceeds a certain number, most recent approaches utilize intelligent optimization methods based on too complex computer science theories to be implemented by an engineering student. In this article we develop and implement new mechanism design results, reducing simultaneously the design space to facilitate finding the optimal mechanism. Finally, we apply global optimization methods that do not require analytical expression of the objective function and are freely available for educational use with Matlab. The proposed computerized methodology focuses student motivation on the mechanical aspects of the problem. Design examples presented illustrate the effectiveness of the approach that provides a solution quality comparable to that of the recently proposed intelligent optimization methods with simplicity of implementation and fast convergence. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 18: 87–92, 2010; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20181

The use of the Hodrick-Prescott (HP) filter is presented as an alternative to the traditional digital filtering and spline smoothing methods currently used in biomechanics. In econometrics, HP filtering is a standard tool used to decompose a macroeconomic time series into a nonstationary trend component and a stationary residual component. The use of the HP filter in the present work is based on reasonable assumptions about the jerk and noise components of the raw displacement signal. Its applicability was tested on 4 kinematic signals with different characteristics. Two are well known signals taken from the literature on biomechanical signal filtering, and the other two were acquired with our own motion capture system. The criterion for the selection of cutoff frequency was based on the power spectral density of the raw displacement signals. The results showed the technique to be well suited to filtering biomechanical displacement signals in order to obtain accurate higher derivatives in a simple and systematic way. Namely, the HP filter and the generalized cross-validated quintic spline (GCVSPL) produce similar RMS errors on the first (0.1063 vs. 0.1024 m/s2) and second (23.76 vs. 23.24 rad/s2) signals. The HP filter performs slightly better than GCVSPL on the third (0.209 vs. 0.236 m/s2) and fourth (1.596 vs. 2.315 m/s2) signals.

In biomechanics studies it is necessary to obtain acceleration of certain parts of the body in order to perform dynamical analysis. The motion capture systems introduce systematic measurement errors that appear in the form of high-frequency noise in recorded displacement signals. The noise is dramatically amplified when differentiating displacements to obtain velocities and accelerations. To avoid this phenomenon it is necessary to smooth the displacement signal prior to differentiation. The use of Singular Spectrum Analysis (SSA) is presented in this paper as an alternative to traditional digital filtering methods. SSA decomposes original time series into a number of additive time series each of which can be easily identified as being part of the modulated signal, or as being part of the random noise. An automatic filtering procedure based in SSA is presented in this work. The procedure is applied to two signals to demonstrate its performance.

Introduction: In the right ventricle (RV), unlike the left ventricle (LV), there is a predominance of longitudinal fibers that are necessary to empty systolic volume against the low pulmonary resistance. The normal longitudinal strain of the RV is -30 to -35% and transversal (radial) strain 20 to 25%. As pulmonary artery hypertension (PAH) develops RV dysfunction, systolic tricuspid regurgitation may be inadequate to estimate the pulmonary pressure.The pulmonary flow acceleration time, TAPSE and tissue Doppler of the tricuspid annulus may infer, but not quantify RV function. Objectives: The aim of this work is to assess with speckle tracking RV strain in patients with PAH and compare the results with data obtained in normal subjects. Methods: Assess RV function parameters (fractional areas, TAPSE and tricuspid regurgitation gradient). Determine longitudinal and transverse strain from the apical view in septum and free wall in patients with PAH and in healthy subjects. Material: 30 PAH patients, mean age 56+/-11 years, 21 male. Results: Among PAH patients and normal subjects, fractional areas were 22% and 46% and TAPSE 1.6 and 2.5 cm. Tricuspid regurgitation gradient was 57 and 19 mmHg. Longitudinal strain -14% and -29% and transverse strain 37% and 22% respectively. Conclusion: Patients with PAH modify the pattern of myocardial strain, with high transversal deformation, probably due to the RV adaptation to the high pressure.Conventional parameters to assess RV function may be masked by the systolic dysfunction of this camera. Disclosure of Interest: None Declared

Background: Orthotic devices are used to help children progressively acquire a more physiologic walking pattern. Methods: To determine the effect of an orthotic device with an out-toeing wedge along with a physiologic shoe as treatment for in-toed gait, angle of gait was measured in 48 children aged 3 to 14 years with in-toed gait. The following comparisons were made: angle of gait in children unshod versus children shod without treatment, angle of gait in children shod without treatment versus children shod plus orthoses, and angle of gait in children unshod versus children shod plus orthoses. Results: Using a correctly fitting shoe increased the angle of gait in a nonsignificant manner, but a significant increase was revealed in the comparison of the angle of gait in children unshod versus children under treatment. The results showed that the behavior in boys and girls was similar to that in the total sample. Regarding side, the corrective effect of the orthotic device was similar in the two feet. However, the data showed a greater corrective effect of the shoe in the right foot. Conclusions: Orthotic devices with out-toeing wedge combined with correctly fitting shoes, as well as shoes alone, are useful tools in the treatment of in-toed gait in children. (J Am Podiatr Med Assoc 100(6): 472–478, 2010)