Master of Science

thesisThis research studies the passive dynamics of an under-actuated trotting quadruped. The goal of this project is to perform three-dimensional (3D) dynamic simulations of a trotting quadruped robot to find proper leg configurations and stiffness range, in order to achieve stable trotting gait. First, a 3D simulation framework that includes all the six degrees of freedom of the body is introduced. Directionally compliant legs together with different leg configurations are employed to achieve passive stability. Compliant legs passively support the body during stance phase and during flight phase a motor is used to retract the legs. Leg configurations in the robot's sagittal and frontal plane are introduced. Numerical experiments are conducted to search the design space of the leg, focusing on increasing the passive stability of the robot. Increased stability is defined as decreased pitching, rolling, and yawing motion of the robot. The results indicate that optimized leg parameters can guarantee passive stable trotting with reduced roll, pitch, and yaw. Studies suggest that a quadruped robot with compliant legs is dynamically stable while trotting. Results indicate that the robot based on a biological model (i.e., caudal inclination of humeri and cranial inclination of femora) has the best performance. Stiff springs at hips and shoulders, soft spring at knees and elbows, and stiff springs at ankles and wrists are recommended. The results of this project provide a conceptual framework for understanding the movements of a trotting quadruped

Entomological survey of phlebotomine sand flies (Diptera: Psychodidae) in a focus of visceral leishmaniasis in central Iran

Background & objectives: Visceral leishmaniasis (VL) is a major vector-borne disease in Iran. A focus of VL is present in Shahreza county, Isfahan province, central Iran. The main objective of this study was to determine the probable vectors in this area. Methods: Sand flies were collected biweekly using sticky paper traps, CDC light-traps, and aspirators from outdoors as well as indoors. All female sand flies were dissected and identified. Promastigotes were inoculated to hamsters and detected by Nested PCR. Approximately 7528 sand flies representing 12 species were collected from April 2003 to October 2004. Phlebotomus (Phlebotomus) papatasi Scopoli, Phlebotomus (Larroussious) major Annandale and Sergentomyia (Sergentomyia) sintoni Pringle were the predominant species. Two percent of P. major was found with natural promastigote infections. Interpretation & conclusion: This is the first report of natural promastigote infection in P. major in central Iran. The activity of P. major started from April and ended in October with a peak in September. The parasites were identified as Leishmania infantum using standard PCR. P. major is a possible vector of leishmaniasis and is susceptible to DDT in this area

Automatic generation and verification of railway interlocking control tables using FSM and NuSMV

Due to the important role in providing safe conditions for train movements, railway interlocking systems are considered as safety critical systems. The reliability, safety and integrity of these systems, relies on reliability and integrity of all stages in their lifecycle including the design, verification, manufacture, test, operation and maintenance. In this paper, the automatic generation and verification of interlocking control tables, as one of the most important stages in the interlocking design process has been focused on, by the safety critical research group in the School of Railway Engineering. Three different subsystems including a graphical signalling layout planner, a control table generator and a control table verifier, have been introduced. Using NuSMV model checker, the control table verifier analyzes the contents of control table besides the safe train movement conditions and checks for any conflicting settings in the table. This includes settings for conflicting routes, signals, points and also settings for route isolation and single and multiple overlap situations. The latest two settings, as route isolation and multiple overlap situations are from new outcomes of the work comparing to works represented on the subject recently

Phage Therapy as a New Approach in Treating Emerging Antibiotic Resistant Infections

Despite the progress in treatment of infectious diseases, ability of microorganisms to develop the resistance to routine antibiotics has still remained as a big global challenge in clinics. This subject matter keeps the infections top in the list of life threatening diseases especially in those individuals suffering from nosocomial infections. The importance of this global health challenge urges researchers to find an alternative solution with more efficacies to treat infections. There are some alternative approaches by which the global spread of resistant bacteria could be controlled. Through these ways, using bacteriophages instead of different generation of antibiotics brings many promises. According to results of different studies using bacteriophages in the management of infectious disease especially in nosocomial infections not only helps to reduce the spread of antibiotics resistance but also raises the hopes for the rescue of the suffering patients. Bacteriophages can open a new therapeutic window in the control and the treatment of the infectious disease with better efficacy.HIGHLIGHTS•Bacteriophage can be used as an antimicrobial agent for treatment of bacterial infection.•Bacterial resistance to routine antibiotics is a big challenge in the world.•Specificity toward bacteria is one of the important characteristic of phages

Medicinal plants and phytotherapy in Iran: Glorious history, current status and future prospects

This study is an endeavour to analyse the status of medicinal plants research in Iran. Because of its exceptional phytogeography, Iran has a unique and diverse flora. It is estimated that, 8167 species of vascular plants are present in Iran of which about 2075 have medicinal importance. Situated at the heart of the Silk Road, Iran enjoys a mix of cultures providing a rich backbone for the development of traditional herbal medicine practices. Notwithstanding the brilliant history in traditional medicine and success of investigation to produce herbal medicines, attempts in recent decades, face many challenges. Many text and paper about these concerns were never translated in English. Strong need was felt to record such data of medicinal plants of Iran, their conservation status and related information. The scattered literature over medicinal plants of Iran were collected, analysed and presented in this review, highlighting not only their therapeutic potential but also concerns about product authenticity, quality, safety and efficacy. This will provide ways for future scientific research in this area. Awareness of critical issues in traditional medicinal herbs can play a pivotal role in the discovery and development of plant based drugs and to sustain consumer confidence

E-LEARNING SEBAGAI MEDIA PEMBELAJARAN INTERAKTIFBERBASIS TEKNOLOGI INFORMASI

The development of science and technology, especially information technology, internet use in education continues to grow. Use of the Internet is not just for distance education, but also developed in the conventional education system. E-learning is a learning model that is created in digital format through an electronic device. Purpose of the use of e-learning in the learning system is to expand access to education public, so that learning modules can be accessed easily, without diabatasi space and time, interactive, and effective. In this paper a prototype using a software development methodology that emphasizes the approach to aspects of design, functionality and user-interface. The final product is expected to be a module-based learning application of information technology. Key words: Internet, the quality of education, information technology, e-learnin

Analysis and modeling of rail maintenance costs

Railroad maintenance engineering plays an important role on availability of roads and reducing the cost of railroad incidents. Rail is of the most important parts of railroad industry, which needs regular maintenance since it covers a significant part of total maintenance cost. Any attempt on optimizing total cost of maintenance could substantially reduce the cost of railroad system and it can reduce total cost of the industry. The paper presents a new method to estimate the cost of rail failure using different cost components such as cost of inspection and cost of risk associated with possible accidents. The proposed model of this paper is used for a real-world case study of railroad transportation of Tehran region and the results have been analyzed

Estimation and assessment of cost and revenue for solid waste management subsystems in Tehran city using mathematical functions

Background and Aims: The municipality of Tehran has recently attempted to implement the integrated waste management system (IWMS) with the approach of minimizing environmental emissions, the lowest cost and the maximum utilization of existing potential. The present study set out with the aim of assessingthe fixed and variable investment costs along with estimating the cost functions of its subsystems.Materials and Methods: Recorded data from September to October in 2014- 2015 were used, making arrangements well in advance. The annual waste input to each subsystems of IWMS was firstly divided into 0 to twice of input ratio. The amount of fixed and variable investment costs along with future costs were then determined considering experts’ opinions. Finally, MATLAB software version 7.1 was used in order to coding, estimating cost functions, and determining the correlation coefficient (R2) between the input and cost values.Results: The results showed that transportation subsystem allocated the maximum amount of costs (43%). Processing (23%), anaerobic digestion (12%), aerobic digestion (9%), landfilling (7%), and incineration (6%) were ranked in the next positions, respectively. Furthermore, using actual cost data based on existing capacity as well as peer reviewed experts’ data with theoretical capacity indicated that all subsystems had economic scale with high correlation coefficients.Conclusion: It is concluded that directing the waste flow from burial site to other waste processing technologies such as separation of recyclable materials, aerobic digestion, anaerobic digestion, and incineration would result in a significant reduction in the total amount of costs.Keywords: Municipal solid waste, Waste management, Mathematical Functions, Operating cost, Unit costFor downloading the full text please click here