Geometry optimization of double wishbone suspension system via genetic algorithm for handling improvement

Motion control, stability maintenance and ride comfort improvement are fundamental issues in design of suspension systems in off-road vehicles. In this paper, a double wishbone (DW) suspension system, mostly used in off-road vehicles, is modeled using ADAMS software. Geometric parameters of suspension system are optimized using genetic algorithm (GA) in a way that ride comfort, handling and stability of vehicle are improved. Simulation results of suspension system and variations of geometric parameters due to road roughness and different steering angles are presented in ADAMS and effects of optimization of suspension system during various driving maneuvers in both optimized and non-optimized conditions are compared. Simulation results indicate that the type of suspension system and geometric parameters have significant effect on vehicle performance

Stress and dynamic analysis of optimized trailer chassis

Članak se bavi dinamičkom i analizom naprezanja lančane sheme šasije kamiona. Najprije se, kako bi se konstruirala šasija najmanje težine, odabiru vrsta materijala i profili poprečnog presjeka šasije u skladu s maksimalnim normalnim naprezanjem i teorijama maksimalne deformacije. Zatim je provedena analiza naprezanja šasije kamiona primjenom ABAQUS softvera u svrhu određivanja maksimalnog poprečnog progiba i raspodjele naprezanja. Rezultati pokazuju da su U-profili dovoljni za smanjenje težine koja može izdržati opterećenja. U sljedećem su koraku razmatrana vibracijska svojstva šasije, što je od velike važnosti za određivanje prirodnih frekvencija konstrukcije. U tu se svrhu provela modalna analiza metodom konačnih elemenata pomoću ANSYS softvera te su određene prirodne frekvencije i oblici vibriranja. U završnom se stupnju dinamički model vozila iskoristio za usporedbu dinamičkih parametara vozila i voznih karakteristika kod optimalizirane i neoptimalizirane šasije. Rezultati simulacije su pokazali da optimalizirana šasija povećava stabilnost kod ljuljanja i poboljšava uvjete u vožnji. Također, da bi se izbjeglo poklapanje frekvencije pobude (ekscitacije) s prirodnom frekvencijom šasije, prirodne frekvencije i oblici vibriranja analizirali su se uz promjene uvjeta opterećenja.This paper discusses the stress and dynamic analysis of truck ladder chassis. At the first stage, in order to design a chassis for self-weight reduction, material type and cross section profiles of chassis are selected according to a maximum normal stress and maximum strain theories. Then, the stress analysis of truck chassis has been carried out by ABAQUS software to determine maximum transverse deflection and stress distribution. Results show that open U-shaped profiles are sufficient for weight reduction which can endure loads. In the next stage, the prediction of the vibrational properties of the chassis which is of great significance in determining the natural frequencies of the structure, are considered. For this purpose, the modal analysis has been accomplished by the finite element packaged ANSYS software, and natural frequencies and mode shapes have been determined. In the final stage, vehicle dynamic model is used to compare vehicle dynamic parameters and ride response in optimized and not optimized chassis conditions. Simulation results clarified that the optimized chassis increases the roll stability and improves ride conditions. Also, in order to avoid matching the natural frequency of the chassis with the excitation frequency, natural frequencies and vibration modes have been analysed during the loading conditions

The Relationship between Psychological Status (Depression and Anxiety) and Social Support and Sexual Function

AbstractIntroduction: Given that large numbers of marital problems arise from lack of proper satisfaction with sexual desire (libido) as well as lack of awareness towards the complicated dimensions of this fundamental motive, the purpose of the present study was to determine correlations between psychological state (depression and anxiety), social support, and sexual function among females of the reproductive age.Methods: This study was a descriptive-analytic research on 400 females referred to clinics affiliated with Shahid Beheshti University of Medical Sciences in the city of Tehran, during year 2015. The study sample was recruited by cluster and multi-stage random sampling method. The Sexual Function Questionnaire, Demographic Questionnaire, Scale of Perceived Social Support, Spielberger’s Anxiety Inventory, and Beck Depression Inventory were also used to collect the data. The obtained data was analyzed through the SPSS software via descriptive statistics, t test, one way Analysis of Variance (ANOVA), as well as chi-square test.Results: The findings revealed that 4.5% of females had poor level of sexual functioning. In addition, 24.5% of females benefited from low social support and also 75% and 9% of the given individuals had chronic depression and severe anxiety, respectively. According to the results of this study, sexual functioning was correlated with female’s age, husband’s age, age of first pregnancy, length of marriage, duration of having private rooms, and history of infertility (P ˂ 0.05). Furthermore, there were relationships between sexual functioning and depression as well as anxiety and social support (P ˂ 0.05).Conclusions: It was concluded that sexual functioning was correlated with psychological state (depression and anxiety) and social support. Thus, it was recommended to conduct screening tests in terms of the variables examined

Development of fuzzy anti-roll bar controller for improving vehicle stability

The main objective of this paper is to develop active control mechanism based on fuzzy logic controller (FLC) for improving vehicle path following, roll and handling performances simultaneously. At the first stage, 3DOF vehicle model which includes yaw rate, lateral velocity (lateral dynamic) and roll angle (roll dynamic) are developed. The controller produces optimal moment to increase stability and roll margin of vehicle by receiving the steering angle as an input and vehicle variables as a feedback signal. The effectiveness of proposed controller and vehicle model are evaluated during fishhook and single lane-change maneuvers. Simulation results demonstrate that FLC by reducing roll angle, lateral velocity and acceleration, vehicle roll resistance and handling properties are improved. Finally the sensitivity and robustness analysis of developed controller for varying longitudinal speeds are investigated

Isolation and identification of diazinon degrading bacteria from fresh water: a case study on the sediments of Lake Parishan in Iran

Diazinon is an organophosphate insecticide which is widely used in various industries. It is known as an important causative of water pollution which eventually redound death of aquatic animals. Today microorganisms are considered as a best choice to reduce environmental pollution. This study was done to identify diazinon degrading bacteria from sediments of Lake Parishan (IRAN) and to evaluate their degrading rate as well. Sampling was done from the surface sediments of Lake Parishan and its surrounding farms during summer, autumn and winter, then incubated in liquid salt medium containing diazinon for 20 days at 35°C. After growing, bacteria were transferred to solid saline medium. They were identified using biochemical tests; thereafter in order to evaluate their ability in degrading of diazinon, diagnostic tests were performed. Result showed that bacteria Pseudomonas, staphylococcus, Bacillus, Corynebacterium, Acinetobacter, Alcaligenes, Serattia, Salmonella, Citrobacter and Providencia are able to degrade diazinon. Among them Pseudomonas was the strongest in summer and winter, while Citrobacter was the most preferable bacterium in fall. It was also detected that combined population of Gram positive and Gram negative bacteria together are able to degrade diazinon faster. Therefore, the present study confirmed the application of bacteria for reducing diazinon pollution in waters considering their ease and economical application

The effectiveness of theory-based intervention in relation to health and food safety in the restaurant staff of Dorud city

Background and Objectives: diseases transmitted through food are a major health problem in developed and developing countries respectively. What health education in the general population and the officers and staff of production and distribution of food is always the best Methods to Prevent Foodborne diseases and the World Health Organization emphasized. The aim of this study is to assess the effectiveness of the theory based on the health and safety of the food in the staff restaurant is the city Dorud. Methods: This study is a randomized controlled trial, 60 employees Dorud city restaurants intervention and control groups in this study are just. And in terms of knowledge and practice in three aspects: personal hygiene, construction and utility work are evaluated. Results: In this study, 60 patients were studied, 17 of the participants operator (28.3) and 43 workers were statistically significant difference was observed between the two groups in terms of demographic variables. between the two groups (Control and test) before intervention education significant differences in terms of awareness, intention, attitude, subjective norm and behavioral control, perceived there, but after the educational program these variables were significantly improved in the intervention group. Conclusion: Our findings showed that educational intervention based on the theory of planned behavior to improve the hygiene of food in the restaurant workers. Keywords: education, theory of planned behavior, food hygiene, staff restauran

Mineralization and structural controls of the AB-Bid carbonate-hosted Pb-Zn (±Cu) deposit, Tabas-Posht e Badam Metallogenic Belt, Iran

Peer ReviewedPostprint (published version

The protective effect of Zataria multiflora Boiss. hydroalcoholic extract on TNF-α production, oxidative stress, and insulin level in streptozotocin-induced diabetic rats

Objective: Oxidative stress leads to reactive oxygen species (ROS) overproduction, which causes tissue injury in diabetic patients. The aim of this study was to evaluate the effects of Zataria multiflora extract on TNF-α, oxidative stress products, and insulin levels as well as lipid profile in diabetic rats. Materials and Methods: Rats were randomly divided into 6 groups of 10 animals. Diabetes was induced by a single injection of streptozotocin (STZ). Control and diabetic control rats orally received 1 mL/day of normal saline, whereas the other three groups received 250, 500 and 1000 mg/kg/day of Z. multiflora extract, and one non-diabetic group orally received 1000 mg/kg/day Z. multiflora extract, for 28 days. At the end of the treatment course, rats were anesthetized and their serum samples were analyzed for TNF-α, malondialdehyde (MDA), super oxide dismutase (SOD), total antioxidant capacity (TAC), lipid profile, total plasma protein, blood glucose, insulin, and liver enzymes levels. Results: Our results showed that cholesterol, LDL, TG, MDA and TNF-α levels decreased, but HDL, SOD, TAC, and total protein increased significantly in the diabetic group receiving 1000 mg/kg Z. multiflora compared to the diabetic control group (

Comments on “Dehydration of hot oceanic slab at depth 30–50 km: key to formation of Irankuh-Emarat Pb-Zn MVT belt, Central Iran” by Mohammad Hassan Karimpour and Martiya Sadeghi

The Malayer-Esfahan Metallogenic belt (MEMB), southwestern Iran, contains numerous different types of the sediment-hosted Zn-Pb (±Ba±Ag), volcanic-sediment hosted Zn-Pb ± Ba, sideritic Fe-Mn-Pb (±Ba±Cu), and barite mineralizations. These deposits are hosted mostly in Jurassic shales and sandstones and in Early to Late Cretaceous carbonates and siltstones with minor volcanic rocks. In contrast to the orogenicrelated Mississippi Valley type (MVT) deposits, the MEMB deposits formed in an extensional back-arc environment and are characterized by their stratabound and stratiform orebodies. In these deposits, silicification and dolomitization (±sericitization) are the main wall-rock alteration styles. The presence of primary laminated sulfides, fine-grained disseminated sphalerite and galena in association with framboidal pyrite, sedimentary structures in sulfide laminae and bands, and the association of some tuffaceous and volcanic rocks with sulfide mineralizations, along with replacement ore textures in the MEMB deposits are not compatible with orogenic-related MVT model for these mineralizations. These characteristics in the Cretaceous MEMB deposits are more compatible with a sub-marine hydrothermal system with sub-seafloor replacement mineralization. Some deposits also share characteristics between Irish type and volcanogenic massive sulfide (VMS) deposits, called VSHMS in this paper. The main argument against the MVT model of Karimpour and Sadeghi (2018) is that this model is not acceptable for the MEMB deposits and could not explain metallogenic aspects of the Zn-Pb (±Ba±Ag) and other mineralizations in this belt.We thank prof. Stefano Albanese, chief editor of Journal of Geochemical Exploration, and two anonymous reviewers for their very useful and constructive comments. The authors are grateful to S. Rezaei for her help in creating the GIS data base of SH Zn-Pb deposits of Iran.Peer ReviewedPostprint (author's final draft

Evaluation of therapeutic potency of human papillomavirus-16 E7 DNA vaccine alone and with interleukin-18 as a genetic adjuvant = Avaliação da potência terapêutica da vacina de DNA do papilomavírus humano-16 E7 isolada e com interleucina-18 como adjuvante genético

OBJETIVOS: Apesar da existência de vacinas preventivas eficazes contra o papilomavírus humano (HPV), são necessárias vacinas terapêuticas que desencadeiem respostas imunes mediadas por células para tratar infecções e malignidades estabelecidas. O objetivo deste estudo foi avaliar a potência terapêutica da vacina de ácido desoxirribonucleico (DNA) HPV-16 E7 isolada e com interleucina (IL)-18. MÉTODOS: Expressões in vitro de IL-18 foram realizadas em células renais embrionárias humanas 293 e confirmadas por Western blotting. A vacina de DNA foi disponibilizada em um estudo anterior. Um total de 45 camundongos fêmeas C57BL/6 divididos em cinco grupos (vacina de DNA, vacina de DNA adjuvada com IL-18, pcDNA3. 1 e solução salina tamponada com fosfato) e foram inoculados com linhagem murina-1 de carcinoma relacionado ao HPV, expressando antígenos E6 / E7 do HPV-16. Os animais foram então imunizados por via subcutânea duas vezes no intervalo de sete dias. A imunidade antitumoral e antígeno-celular específica foi avaliada pela proliferação de linfócitos (ensaio de brometo de 3- [4,5-dimetiltiazol-2-il] -2,5-difeniltetrazólio: MTT), ensaio de liberação de lactato desidrogenase, ensaio de IL-4 e ensaio de interferon-gama [IFN-γ]. O tamanho do tumor foi seguido por 62 dias. RESULTADOS: O ensaio MTT, que mede a proliferação de linfócitos em resposta ao antígeno específico, aumentou nos grupos de coadministração e de vacina de DNA em comparação aos grupos controle e adjuvante genético (p <0,001). Os camundongos imunizados com a coadministração geraram significativamente mais IFN-γ e IL-4 do que os outros camundongos imunizados (p<0,001) A redução do tamanho do tumor nos grupos de coadministração e de vacina de DNA foi significativamente mais acentuada do que nos grupos controle e adjuvante genético (p<0,001), mas não houve nenhuma diferença estatisticamente significativa entre os grupos vacina de DNA e coadministração (p=0,15). CONCLUSÕES: A IL-18 como adjuvante genético e a vacina de DNA E7 aumentaram as respostas imunes em sistemas modelo de camundongos contra o câncer cervical. No entanto, o uso de IL-18 como adjuvante genético com a vacina de DNA E7 não teve efeito sinérgico significativo nas respostas imunes in viv