Sharif Digital Repository

Assessment of respiratory volume is widely used in clinical application in order to assess the case of respiratory illness, and the progression of the respiratory syndrome. Respiratory plethysmography is used to determine the changes of chest volume to monitor the breathing. A wearable respiration measuring system has been introduced for detection of volume variations of chest. The system consists of a flexible sensor, stretchable cloth and electrical board. The flexible sensor, whose electrical voltage is produced by body movements, is installed inside the shirt and closely contacts the chest. The low frequency components of body movements recorded by the sensor are mainly generated by... 

Assessment of respiratory volume is extensively performed in clinical applications in order to assess the cases of respiratory illness and the progression of the respiratory syndromes. Respiratory plethysmography is employed to determine the changes of chest volume to monitor breathing. A wearable respiration measuring system has been introduced to detect volume variations of chests. The system consists of a flexible sensor, stretchable cloth and electrical board. The flexible sensor, which measures electrical voltage produced by extension movements, is installed inside the shirt and nearly contacts the chest. The system can be used everywhere and be self-applied by patients. The main... 

The most prevalent musculoskeletal condition and one of the most disabilities are caused by low back pain. In the low back pain, a large variety of evaluation tools is presented to assess the results of the treatment; therefore, it is important to measure the trunk angle in order to determine the progress during patient's treatment. In this project, we developed a low cost prototype system for flexion-extension movement to measure the angle of the trunk in sagital plane. The system consists of clothing that is stretchable; a Rubbery Ruler sensor (RRs) attached on clothing, data acquisition system. Inertial Magnetic Unit (IMU) sensor installed on spine is used to calibrate the orientation for... 

In the shoulder disease, a large various tools is employed to assess the results of the treatment. In this work, a new system is proposed to record abduction-adduction movement of human shoulder. The system consists of a cloth that is stretchable, two Rubbery Ruler sensors (RRs) that attached on humerus of both arms and a data acquisition system. Two Xsens sensors attached on humerus of both arms are used to calibrate the orientation for the RRs output. Moreover, we developed a low cost prototype system to measure the rotation of Yaw from 30 to 90 degrees  

Wearable system is a proper solution for rehabilitation and instrumentation applications for human daily activities. Recently, several researches are concentrated on this technology significantly because of new progress in sensors and fusion sensors. In the near future, wearable and ambulatory devices will be used considerably in biomedical applications. In this study, we reviewed some methods about wearable measuring system then introduced and designed innovative wearable clothing for this purpose. Some specifications and advantages of our system in comparison with relevant researches are; using painted sensors that are manufactured through nano electro active polymer technology, low... 

Purpose - the purpose of this study is the measuring of the human movement using printed wearable sensor. Human movement measurement is one of the usages for wearable sensors. This technology assists the researchers to collect data from the daily activities of individuals. In other words, the kinematics data of human motion will be extracted from this data and implemented in biomechanical aspects. Design/methodology/approach - This study presents an innovative printed wearable sensor which can be used for measuring human movement orientations. In this paper, the manufacturing process, implementation, measurement setup and calibration procedure of this new sensor will be explained, and the... 

The interest in wearable systems among the biomedical engineering and clinical community continues to escalate as technical refinements enhance their potential use for both indoor and outdoor applications. For example, an important wearable technology known as a microelectromechanical system (MEMS) is demonstrating promising applications in the area of biomedical engineering. Accordingly, this study was designed to investigate the Sharif-Human Movement Instrumentation System (SHARIF-HMIS), consisting of inertial measurement units (IMUs), stretchable clothing, and a data logger—all of which can be used outside the controlled environment of a laboratory, thus enhancing its overall utility.... 

Human movement analysis is an important part of biomechanics and rehabilitation, for which many measurement systems are introduced. Among these, wearable devices have substantial biomedical applications, primarily since they can be implemented both in indoor and outdoor applications. In this study, a Trunk Motion System (TMS) using printed Body‐Worn Sensors (BWS) is designed and developed. TMS can measure three‐dimensional (3D) trunk motions, is lightweight, and is a portable and non‐invasive system. After the recognition of sensor locations, twelve BWSs were printed on stretchable clothing with the purpose of measuring the 3D trunk movements. To integrate BWSs data, a neural network data... 

Wearable measuring system has major effects on biomechanics of human movements especially in daily activities in order to monitor and analyze the human movements to achieve the most important kinematics parameters. In the recent decade, inertial sensors were utilized by researchers in order to developing wearable system for instrumentation of human movements. In this study, Sharif-Human Movement Instrumentation System (SHARIF-HMIS) was designed and manufactured. The system consists of inertial measurement units (IMUs), stretchable clothing and data logger. The IMU sensors are installed on the human body. The system can be used at home and also industrial environments. The main features of... 

The vacuum sector of the Brans-Dicke theory is studied from the viewpoint of a non-conformally invariant gravitational model. We show that, this theory can be conformally symmetrized using an appropriate conformal transformation. The resulting theory allows a particle interpretation, and suggests that the quantum aspects of matter may be geometrized  

We derive exact dispersion relations for axial and flexural elastic wave motion in a rod and a beam under finite deformation. For axial motion we consider a simple rod model, and for flexural motion we employ the Euler-Bernoulli kinematic hypothesis and consider both a conventional transverse motion model and an inextensional planar motion model. The underlying formulation uses the Cauchy stress and the Green-Lagrange strain without omission of higher order terms. For all models, we consider linear constitutive relations in order to isolate the effect of finite motion. The proposed theory, however, is applicable to problems that also exhibit material nonlinearity. For the rod model, we... 

5-Ammonium valeric acid (AVA) is a frequently used additive in the preparation of lead halide perovskites. However, its microscopic role as passivating, cross-linking, or templating agent is far from clear. In this work, we provide density functional theory-based structural models for the Ruddlesden-Popper (RP) phases of AVA2(CH3NH3)n-1PbnI3n+1 for n = 1, 2, and 3 and validate with experimental data on polycrystalline samples for n = 1. The structural and electronic properties of the AVA-based RP phases are compared to the ones of other linker families. In contrast to aromatic and aliphatic spacers without additional functional groups, the RP phases of AVA are characterized by the formation... 

The characteristics of a cavitation water tunnel test setup and the experiments of cavitation around a circular cylinder with free stream turbulence are presented in this paper. The Reynolds number of flow is limited in the range of 1.26 × 105 to 3 × 105 and the far upstream flow has free turbulence. Drag force, back pressure, location of cavitation inception, length of cavity and appearance of cavitation are measured or observed and their results are presented here. It was found that the cavitation effects on the boundary layer and separation of flow over the cylinder and drag force become minimum at the cavitation number of 1.94. The cavitation inception occurs in the sub-layer and at an... 

The respiratory system is a vital organ system which makes breathing and gas exchange possible for human's body. The loss of functionality in this system is due to either genetical problems or environmental issues like pollution or toxic gases which in many cases is inevitable. These circumstances may cause different respiratory diseases which may not be curable presently but their side effects can be partly controlled by careful and timely analysis improving the quality of patient's life. So, an appropriate device for conducting different analysis can be effective for people who suffer from respiratory diseases such as chronic obstructive pulmonary disease (COPD), asthma, occupational lung... 

We consider the problem of minimizing rank of a matrix under linear and nonlinear matrix inequality constraints. This problem arises in diverse applications such as estimation, control and signal processing and it is known to be computationally NP-hard even when constraints are linear. In this paper, we first formulize the RMP as an optimization problem with linear objective and simple nonlinear semialgebraic constraints. We then proceed to solve the problem with augmented Lagrangian method known in nonlinear optimization. Despite of other heuristic and approximate methods in the subject, this method guarantees to find the global optimum in the sense that it does not depends on the choice of... 

In this paper, the intra-cell link adaptation problem is formulated as a constrained nonconvex nondifferentiable optimization problem to maximize the average link throughput while guaranteeing the best possible coverage reliability. We proceed to solve the resulted nonsmooth optimization problem using proximal point bundle method known in nondifferentiable optimization context. For this purpose, we first exploit the problem structure and reduce the original large scale optimization problem to a sequence of one-dimensional problems coordinated by a master program using direct primal decomposition technique. Proximal bundle method with aggregation policy is then adopted in master program to... 

The kinetics and equilibrium of isomerization reaction of D-glucose to D-fructose have been investigated using a commercial immobilized glucose isomer ase (IGI), Sweetzyme type IT®, in a batch stirred-tank reactor. The batch experimental data were used to model the reaction kinetics using the well-known Michaelis-Menten rate expression. The kinetic model was utilized in a dynamic-mathematical model for a packed-bed reactor to predict the concentration profiles of D-glucose and D-fructose within the reactor. The experimental results for the fractional conversion of D-glucose in the packed-bed reactor of IGI catalyst indicated that the model prediction of the transient and steady-state... 

Proton exchange membrane fuel cell (PEM-FC) aggregation pressure causes extensive strains in cell segments. The compression of each segment takes place through the cell modeling method. In addition, a very heterogeneous compressive load is produced because of the recurrent channel rib design of the dipole plates, so that while high strains are provided below the rib, the domain continues in its initial uncompressed case under the ducts approximate to it. This leads to significant spatial variations in thermal and electrical connections and contact resistances (both in rib–GDL and membrane–GDL interfaces). Variations in heat, charge, and mass transfer rates within the GDL can affect the... 

Proton exchange membrane fuel cell (PEM-FC) aggregation pressure causes extensive strains in cell segments. The compression of each segment takes place through the cell modeling method. In addition, a very heterogeneous compressive load is produced because of the recurrent channel rib design of the dipole plates, so that while high strains are provided below the rib, the domain continues in its initial uncompressed case under the ducts approximate to it. This leads to significant spatial variations in thermal and electrical connections and contact resistances (both in rib–GDL and membrane–GDL interfaces). Variations in heat, charge, and mass transfer rates within the GDL can affect the... 

Establishing high-quality communication in construction projects is essential to securing successful collaboration and maintaining understanding among project stakeholders. Indeed, poor communication results in low productivity, poor efficiency, and substandard deliverables. While high-quality communication is recognized as contingent on the interpersonal skills of workers, the impacts of communication quality on job performance remain unknown. This study addresses this deficiency by developing a method to evaluate construction workers' communication quality. A literature review is undertaken to capture salient interpersonal skills. Leadership style, listening, team building, and clarifying...