Road profile estimation using wavelet neural network and 7-DOF vehicle dynamic systems

Ali Solhmirzaei,Shahram Azadi,Reza Kazemi 대한기계학회 2012 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.26 No.10

Road roughness is a broad term that incorporates everything from potholes and cracks to the random deviations that exist in a profile. To build a roughness index, road irregularities need to be measured first. Existing methods of gauging the roughness are based either on visual inspections or using one of a limited number of instrumented vehicles that can take physical measurements of the road irregularities. This paper more specifically focuses on the estimation of a road profile (i.e., along the "wheel track"). This paper proposes a solution to the road profile estimation using a wavelet neural network (WNN) approach. The method incorporates a WNN which is trained using the data obtained from a 7-DOF vehicle dynamic model in the MATLAB Simulink software to approximate road profiles via the accelerations picked up from the vehicle. In this paper, a novel WNN, multi-input and multi-output feed forward wavelet neural network is constructed. In the hidden layer, wavelet basis functions are used as activate function instead of the sigmoid function of feed forward network. The training formulas based on BP algorithm are mathematically derived and a training algorithm is presented. The study investigates the estimation capability of wavelet neural networks through comparison between some estimated and real road profiles in the form of actual road roughness.

Exact stability of a platoon of vehicles by considering time delay and lag

Ali Ghasemi,Reza Kazemi,Shahram Azadi 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.2

The problem of controlling a string of vehicles moving in one dimension is considered so that they all follow a lead vehicle with constanttime headway spacing between successive vehicles. Due to realistic design and execution, the negative effect of the tracking lagparameter and time delay is taken into account. By applying an acceleration feedforward, the distance error of each vehicle will be independentof the behavior of other vehicles. As a result, the vehicle is better able to track a desired trajectory, which improves the stringstability. Cluster treatment of characteristic roots (CTCR) paradigm is utilized to reveal the stabilizing parametric regions in the domainof the time delay to render the stability of closed loop system. The string stability analysis is performed to evaluate the disturbance attenuation. Finally, an example of multiple vehicle platoon control is presented, which demonstrates the effectiveness of the proposedmethod.

Effect of parameters on roll dynamic response of an articulated vehicle carrying liquids

Shahram Azadi,Ali Jafari,Masoud Samadian 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.3

Directional response and roll stability characteristics of a partly filled tractor semi-trailer vehicle, with cylindrical tank, under differentparameters and conditions are investigated. The effective parameters and conditions in the stability of a tractor semi-trailer carrying liquidcan be considered as filled volume, kinematic viscosity of liquid cargo and vehicle steering input. The dynamic interaction of liquid cargowith the tractor semi-trailer vehicle is evaluated by integrating a dynamic slosh model of the partly filled tank with five-degrees-offreedomof a tractor semi-trailer tank model. The dynamic fluid slosh within the tank is modeled using three-dimensional Navier-Stokesequations, coupled with the volume-of-fluid equations and analyzed using FLUENT software. The coupled tank-vehicle model is subsequentlyanalyzed to determine the roll stability characteristics for different conditions and maneuvers. The results show effects of parametervariations on roll stability of the vehicle carrying liquid and also fluid's behavior in interaction with a vehicle's dynamics.

Study of Genesis, Morphology and Clay Mineralogy in Kakan Area, Kohgiluyeh-Va-Buyer-Ahmad Province, Iran

Sirous Shakeri,Seyed Ali Abtahi,Hamidreza Owliaie,Abolfazl Azadi 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

Numerical Modeling of Tropical Cyclone-Induced Storm Surge in the Gulf of Oman Using a Storm Surge–Wave–Tide Coupled Model

Siahsarani Amir,Karami Khaniki Ali,Aliakbari Bidokhti Abbas-Ali,Azadi Majid 한국해양과학기술원 2021 Ocean science journal Vol.56 No.3

A storm surge is a complex phenomenon in which current, tide, and waves interact with each other. Even if the wind is the main force of driving the surge, waves and tide are also key factors that affect the momentum and mass transport during the storm surge. Although, the Iranian Makran coastal region in the Gulf of Oman is vulnerable to storms and coastal hazards, the interaction of waves on the storm surge has not yet been studied in this region. This paper aims to investigate tropical cyclone-induced waves and storm surges in the Gulf of Oman through the wave-tide-circulation coupled system. The simulations were carried out using the two-way coupling of wave and hydrodynamic models (MIKE 21 SW + MIKE 3 HD) to compute the wave characteristics and water levels during the super cyclone Gonu, which were validated with the field measurements. Model results, and in particular the water level and significant wave height, agreed well with the observations during the Gonu storm’s period. Also, the influences of the key factors interaction (wind, atmospheric pressure, and wave) on a storm surge in the Iranian Makran coasts were evaluated. First, there is a peak surge caused by winds, after that the surges induced by the wave and atmospheric pressure. The wind, pressure, and wave have a contribution of 77.9%, 22.3%, and 10.3%, respectively, in inducing the peak surge of the storm. Key findings of this study indicate the importance of wave-induced setup due to radiation stress as well as the role of the coupled model inaccurate storm surge simulation.

Minimally invasive search for a missing vibrator

( Greg J Marchand ),( Ali Azadi ),( Akarshi Kaue Brar ),( Katelyn Sainz ),( Sienna Anderson ),( Stacy Ruther ),( Kelly Ware ),( Sophia Hopewell ),( Giovanna Brazil ),( Katerina Meassick ),( Hannah Wol 대한산부인과학회 2020 Obstetrics & Gynecology Science Vol.63 No.5

Objective To report a unique surgical procedure that was utilized to locate a missing vibrator in the pelvis of a patient. Emergency room admissions and surgery secondary to the malfunctioning of devices intended for sexual stimulation are extremely common. Emergency room staff of hospitals in the United States usually are skilled in the detection and removal of these devices. Occasionally, surgical intervention is warranted if the device enters a cavity that cannot safely be explored in the emergency room setting. We report a case of a vibrator that was lost during sexual activity. A flat plate X-ray showed it to be in the abdominal cavity. Careful questioning of the patient revealed that the device had an unusually small diameter. Surgical intervention showed that the device ultimately ended up in the bladder without causing traumatic injury. Methods We created a narrated video to demonstrate the surgical procedure (Canadian Task Force Classification III). Results Laparoscopy and cystoscopy were used to visualize and successfully remove the device. The patient recovered uneventfully. Conclusion Following laparoscopic confirmation of the location of the device, it was removed via cystoscopy. This case demonstrates how background information, such as the size of the missing device in this case, can be critical to providing high quality patient care.

Multidisciplinary optimization of a stiffened shell by genetic algorithm

Mahdi Maghsoudi Mehrabani,Ali Asghar Jafari,Mohammad Azadi 대한기계학회 2012 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.26 No.2

Vibration analysis of simply supported rotating cross-ply laminated stiffened cylindrical shell is performed using an energy approach which includes variational and averaging method. The stiffeners include rings and stringers. The equations are obtained by Rayleigh-Ritz method and Sander’s relations. To validate the present method, the results are compared to the results available in other literatures. A good adoption is observed in different type of results including isotropic shells, rotating laminated shells, stiffened isotropic shells and stiffened laminated shells. Then, the optimization of parameters due to shell and stiffeners is conducted by genetic algorithm (GA) method under weight and frequency constraints. Stiffener shape, material properties and dimensions are also optimized.

Management of interstitial pregnancy in the era of laparoscopy: a meta-analysis of 855 case studies compared with traditional techniques

( Greg Marchand ),( Ahmed Taher Masoud ),( Anthony Galitsky ),( Ali Azadi ),( Kelly Ware ),( Janelle Vallejo ),( Sienna Anderson ),( Alexa King ),( Stacy Ruther ),( Giovanna Brazil ),( Kaitlynne Ciemi 대한산부인과학회 2021 Obstetrics & Gynecology Science Vol.64 No.2

Interstitial pregnancy is a rare, life-threatening condition that requires high clinical suspicion for diagnosis. Most cases are discovered after complications have occurred. Many authors have described laparoscopic management. Although previous systematic reviews have compared the attributes and complications associated with interstitial pregnancy, we endeavored to complete the first systematic review and meta-analysis to compare the laparoscopic treatment of interstitial pregnancy with the open approach in the modern age of laparoscopic surgery. We systematically searched PubMed, ClinicalTrials.gov, Scopus, Web of Science, and Cochrane until June 2020 using relevant keywords and screened them for eligibility. We found a statistically significant difference in blood loss between laparoscopic and open surgery (168 mL compared to 1,163 mL). Further, cumulative meta-analysis has revealed that blood loss in laparoscopy has been decreasing over time from 1991 to 2020. Laparoscopic patients took less operative time (63.2 minutes) compared to laparotomy patients (78.2 minutes). Patients in the laparoscopic group spent less time hospitalized (3.7 days) compared to laparotomy patients (5.2 days). Our findings add strength to the position that laparoscopic approaches to interstitial pregnancy can be considered first-line in most situations. The laparoscopic approach was found to have a mean blood loss of 168 mL, and this blood loss seems to decrease over time. Increased gravidity and duration of amenorrhea are positive factors that increase bleeding during the procedure. We are unable to find enough high-quality data to significantly compare successful pregnancy following surgery or risk of mortality in these populations.

Supportive Care Needs of Iranian Cancer Survivors and Relationships with Social Support

Faghani, Safieh,Mohammadian, Robab,Rahmani, Azad,Mohajjel-Aghdam, Ali-Reza,Hassankhani, Hadi,Azadi, Arman Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.15

Background: Assessment of supportive care needs of cancer survivors and identifying factors affecting such needs is important for implementation of any supportive care programs. So, the aims of present study were to investigate the supportive care needs of Iranian cancer survivors and relationships with social support. Materials and Methods: In this descriptive-correlational study two hundred and fifty cancer survivors participated via convenient sampling methods. The Supportive Care Needs Survey (SCNS-SF34) and Multidimensional Scale of Perceived Social Support (MSPSS) were used for data collection. SPSS software was applied and univariate regression was used for examine relationships of supportive care needs with social support. Results: Participants demonstrated many unmet supportive care needs, especially in health system and information and psychological domains. In addition, participants reported that family members and significant others were their main source of support. Also, social support has a significant correlation with all domains of supportive care needs. Conclusions: There is an indispensable need for establishment of supportive care programs for Iranian cancer survivors. In addition, family members of family members of such survivors are an important resource to help develop such programs.

Perceptions of Iranian Cancer Patients Regarding Respecting their Dignity in Hospital Settings

Avestan, Zoleikha,Rahmani, Azad,Heshmati-Nabavi, Fatemeh,Mogadasian, Sima,Faghani, Safieh,Azadi, Arman,Esfahani, Ali Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.13

Background: There are several factors that threaten the dignity of cancer patients in hospital settings. However, there is limited literature regarding the degree to which dignity of cancer patients is actually respected in daily clinical practice. The aims of this study were therefore to explore cancer patient perceptions of respecting their dignity and related variables in an Iranian cancer specific center. Materials and Methods: This descriptive-correlational study was carried out among 250 cancer patients admitted to a cancer specific center in East Azerbaijan Province, Iran. These patients were selected using a convenience sampling method. The Patient Dignity Inventory (PDI) was used for data collection. Descriptive and inferential statistics were used for data analysis. Results: The patients' scores in 18 out of 25 items of PDI were 3 or greater which indicate the importance of considering these items in clinical settings. Also, the score of patients in three sub-scales of PDI including illness-related concerns, personal dignity, and social dignity were 74, 65 and 57, respectively (based on a total 100). The overall score of PDI was statistically associated with age, history of disease recurrence, education, employment and economic status of participants. Conclusions: According to the study findings the dignity of Iranian cancer patients is not completely respected in clinical settings which require special considerations. As nurses spend more time at patients' bedsides, they have an important role in maintaining and promoting dignified care.