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81.
Hadi Kalani Alireza Akbarzadeh S. Nader Nabavi Sahar Moghimi 《Intelligent Service Robotics》2018,11(2):187-205
Human mastication is a complex and rhythmic biomechanical process which is regulated by a brain stem central pattern generator (CPG). Masticatory patterns, frequency and amplitude of mastication are different from person to person and significantly depend on food properties. The central nervous system controls the activity of muscles to produce smooth transitions between different movements. Therefore, to rehab human mandibular system, there is a real need to use the concept of CPG for development of a new methodology in jaw exercises and to help jaw movements recovery. This paper proposes a novel method for real-time trajectory generation of a mastication rehab robot. The proposed method combines several methods and concepts including kinematics, dynamics, trajectory generation and CPG. The purpose of this article is to provide a methodology to enable physiotherapists to perform the human jaw rehabilitation. In this paper, the robotic setup includes two Gough–Stewart platforms. The first platform is used as the rehab robot, while the second one is used to model the human jaw system. Once the modeling is completed, the second robot will be replaced by an actual patient for the selected physiotherapy. Gibbs–Appell’s formulation is used to obtain the dynamics equations of the rehab robot. Then, a method based on the Fourier series is employed to tune parameters of the CPG. It is shown that changes in leg lengths, due to the online changes of the mastication parameters, occur in a smooth and continuous manner. The key feature of the proposed method, when applied to human mastication, is its ability to adapt to the environment and change the chewing pattern in real-time parameters, such as amplitudes as well as jaw movements velocity during mastication. 相似文献
82.
U-type and two-sided assembly lines are two types of design having advantages over traditional straight assembly lines. In this paper, a new line design hybrid of U-type and two-sided lines is presented. A bi-objective 0-1 integer programming model is developed to solve the line balancing problem of the proposed design. Zoning constraints are also considered for the proposed design. A number of test problems from the literature with up to 65 tasks are solved. Benefits of two-sided U-type lines are discussed. 相似文献
83.
Mohammad A. Altamimi Mohsin Kazi Mshaan Hadi Albgomi Abdul Ahad Mohammad Raish 《Drug development and industrial pharmacy》2013,39(7):1073-1078
The purpose of this work is to develop novel lipid-based self-nanoemulsifying drug delivery systems (SNEDDS) as carriers for transdermal delivery of curcumin. SNEDDS containing black seed oil, medium chain mono- and diglycerides and surfactants, were prepared as curcumin delivery vehicles. Their formation spontaneity, morphology, droplet size, and drug loading were evaluated. Gel preparation containing two of the SNEDDS formulations were used in the carrageenan induced paw edema to evaluate the anti-inflammatory effect. Results showed droplet size as low as 71?nm. The highest drug loading was observed with SNEDDS-F6 of ～45?mg/g. In in-vivo investigation, SNEDDS-F6 exhibited significant anti-inflammatory activities in terms of 80% reduction in paw edema when compared with positive control. The prepared SNEDDS with the elevated entrapment efficiency, good transdermal penetration ability could be a suitable candidate for effective transdermal curcumin skin delivery. 相似文献
84.
Hadi Valizadeh Mohammad Pourmahmood Javid Shahbazi Mojarrad Mahboob Nemati Parvin Zakeri-Milani 《Drug development and industrial pharmacy》2013,39(4):396-407
The objective of this study was to forecast and optimize the glucosamine production yield from chitin (obtained from Persian Gulf shrimp) by means of genetic algorithm (GA), particle swarm optimization (PSO), and artificial neural networks (ANNs) as tools of artificial intelligence methods. Three factors (acid concentration, acid solution to chitin ratio, and reaction time) were used as the input parameters of the models investigated. According to the obtained results, the production yield of glucosamine hydrochloride depends linearly on acid concentration, acid solution to solid ratio, and time and also the cross-product of acid concentration and time and the cross-product of solids to acid solution ratio and time. The production yield significantly increased with an increase of acid concentration, acid solution ratio, and reaction time. The production yield is inversely related to the cross-product of acid concentration and time. It means that at high acid concentrations, the longer reaction times give lower production yields. The results revealed that the average percent error (PE) for prediction of production yield by GA, PSO, and ANN are 6.84, 7.11, and 5.49%, respectively. Considering the low PE, it might be concluded that these models have a good predictive power in the studied range of variables and they have the ability of generalization to unknown cases. 相似文献
85.
This study investigated the feasibility of using two types of waste glass sand as fine aggregate replacement in ambient cured alkali-activated mortars (AAMs). Fly ash (FA) and ground granulated blast furnace slag were used as aluminosilicate source materials to produce the AAMs. The waste glass sand was used to replace 0%, 25%, 50%, 75%, and 100% fine aggregate (by mass) in AAMs. The influences of the use of waste glass sand, for the replacement of fine aggregate, on slump flow, setting time, compressive strength, and flexural strength of ambient cured AAMs were evaluated. It was found that the slump flow and setting time of ambient cured AAMs significantly increased as the percentage of replacement of fine aggregate by waste glass sand increased. However, the compressive and flexural strengths of ambient cured AAMs decreased when 50% and over fine aggregate were replaced by waste glass sand. The ambient cured AAMs with 25% replacement of fine aggregate with waste glass sand achieved the highest compressive and flexural strengths. Scanning electron microscope analysis indicated that the increase in the compressive strength and flexural strength of AAMs was due to the bridging-like effect and filling effect provided by the waste glass sand. The use of waste glass sand as a partial replacement of fine aggregate in ambient cured AAMs was found to be feasible. In addition, 25% of the fine aggregate replaced by waste glass sand resulted in the best mechanical properties for ambient cured AAMs. 相似文献
86.
Mostafa Noohi Ali Mirvakili Hadi Safdarkhani Sayed Alireza Sadrossadat 《ETRI Journal》2023,45(3):519-533
This paper implements a simultaneous solar and thermal energy harvesting system, as a hybrid energy harvesting (HEH) system, to convert ambient light into electrical energy through photovoltaic (PV) cells and heat absorbed in the body of PV cells. Indeed, a solar panel equipped with serially connected thermoelectric generators not only converts the incoming light into electricity but also takes advantage of heat emanating from the light. In a conventional HEH system, the diode block is used to provide the path for the input source with the highest value. In this scheme, at each time, only one source can be handled to generate its output, while other sources are blocked. To handle this challenge of combining resources in HEH systems, this paper proposes a method for collecting all incoming energies and conveying its summation to the load via the current mirror cells in an approach similar to the maximum power point tracking. This technique is implemented using off-the-shelf components. The measurement results show that the proposed method is a realistic approach for supplying electrical energy to wireless sensor nodes and low-power electronics. 相似文献
87.
Hadi Ahmadi Ehsan Hosseini Withita Cha-Umpong Mojtaba Abdollahzadeh Asghar Habibnejad Korayem Amir Razmjou Vicki Chen Mohsen Asadnia 《Advanced Materials Technologies》2021,6(10):2000665
Lithium consumption is estimated to face a considerable rise in the next decade; thus, finding new reproducible lithium resources such as brine deposits and seawater has become a fast-growing research topic. However, Li+ extraction from these resources is challenging due to its low concentration and presence of other monovalent cations exhibiting identical chemical properties. Here, it is discovered that tannic acid (TA) inside graphene oxide (GO) nanochannel acts as natural ion trapper, which possesses lithiophilic elements. The lithium-rich feed is achieved by using the potential-driven TA-GO membrane by excluding lithium ions from other monovalent cations. The results showed that the ion trapping capability of inexpensive TA-GO membrane is Li+ > Na+ > K+ with Li trapping energy of − 593 KJ mol−1, respectively, where its trapping efficiency goes into a top rank among their expensive synthetic counterparts. Evaluating the combined effect of three key parameters, including barrier energy, hydration energy, and binding energy illustrates that required energy to transport Li-ion through the membrane is higher than that for other monovalent. This proof-of-concept work opens up an avenue of research for designing a new class of ion-selective membranes, based on the incorporation of naturally low cost available lithiophilic guest molecules into 2D membranes. 相似文献
88.
Mohamed Shehata Draz Maryam Moazeni Manasa Venkataramani Harini Lakshminarayanan Ecem Saygili Nivethitha Kota Lakshminaraasimulu Kamyar Mehrabi Kochehbyoki Manoj Kumar Kanakasabapathy Shirin Shabahang Anish Vasan Mohamad Ali Bijarchi Adnan Memic Hadi Shafiee 《Advanced functional materials》2018,28(26)
A low‐cost and easy‐to‐fabricate microchip remains a key challenge for the development of true point‐of‐care (POC) diagnostics. Cellulose paper and plastic are thin, light, flexible, and abundant raw materials, which make them excellent substrates for mass production of POC devices. Herein, a hybrid paper–plastic microchip (PPMC) is developed, which can be used for both single and multiplexed detection of different targets, providing flexibility in the design and fabrication of the microchip. The developed PPMC with printed electronics is evaluated for sensitive and reliable detection of a broad range of targets, such as liver and colon cancer protein biomarkers, intact Zika virus, and human papillomavirus nucleic acid amplicons. The presented approach allows a highly specific detection of the tested targets with detection limits as low as 102 ng mL?1 for protein biomarkers, 103 particle per milliliter for virus particles, and 102 copies per microliter for a target nucleic acid. This approach can potentially be considered for the development of inexpensive and stable POC microchip diagnostics and is suitable for the detection of a wide range of microbial infections and cancer biomarkers. 相似文献
89.
Hadi Azmi Mohammad Javad Khosrowjerdi 《International Journal of Adaptive Control and Signal Processing》2017,31(12):1885-1902
This paper presents 2‐novel linear matrix inequality (LMI)‐based adaptive output feedback fault‐tolerant control strategies for the class of nonlinear Lipschitz systems in the presence of bounded matched or mismatched disturbances and simultaneous occurrence of actuator faults, including failure, loss of effectiveness, and stuck. The constructive algorithms based on LMI with creatively using Lyapunov stability theory and without the need for an explicit information about mode of actuator faults or fault detection and isolation mechanism are developed for online tuning of adaptive and fixed output‐feedback gains to stabilize the closed‐loop control system asymptotically. The proposed controllers guarantee to compensate actuator faults effects and to attenuate disturbance effects. The resulting control methods have simpler structure, as compared with most existing recent methods and more suitable for practical systems. The merits of the proposed fault‐tolerant control scheme have been verified by the simulation on nonlinear Boeing 747 lateral motion dynamic model subjected to actuator faults. 相似文献
90.
In recent years, addition of nanoparticles to fluids and polymers has been used as a way of modifying rheological properties. Poly(vinyl alcohol) (PVA) and titanium dioxide (TiO2) nanoparticles aqueous composite nanofluids were prepared through the use of ultrasonic vibration. In fact, ultrasonic vibration is an advantageous method for nanoparticle dispersion. The preparation method prevents reduction of the polymer's molecular weight. TiO2 nanoparticles with different concentrations were employed to investigate the rheological characteristics of composite nanofluids. Rheological characteristics of base fluids and composite nanofluids were measured at different temperatures. Based on the results, all composite nanofluids, as well as base fluids, exhibited non‐Newtonian behavior and rheological characteristics of composite nanofluids, following the Herschel‐Bulkley model. In addition, model parameters are functions of temperature, PVA, and TiO2 nanoparticle concentrations. Also, two‐way interactions among temperature, PVA, and TiO2 nanoparticle concentrations affect flow index and consistency index of the Herschel‐Bulkley model. J. VINYL ADDIT. TECHNOL., 23:234–240, 2017. © 2015 Society of Plastics Engineers 相似文献