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A modular robotic system and its fuzzy logic based controller are proposed for use in logging operations in forest environments with steep slopes. The Log-Carrying Robot (LCR) concept is composed of two modular wheeled robotic agents with individual wheel steering that connect to the ends of a log to a form a centrally controlled robot. A fuzzy controller specifies the desired direction of travel using four factors: the presence of obstacles, boundaries limiting the robot’s travel space, the heading of the goal position relative to the robot, and the slope of the terrain. The capabilities of the proposed controller are demonstrated in simulation using a rectangular robot with four individually actuated and steered wheels. Results indicate that the controller successfully steers the robot towards the goal position while avoiding obstacles using only eleven fuzzy rules. Additionally, the simple rules are shown to be effective at automatically compensating for sloped terrain by avoiding direct travel down hills, as well as adapting for various robot lengths.

Abstract Background Relapse of tuberculosis (TB) may develop as the result of reactivation of the endogenous primary infection, or as a result of a exogenous reinfection. This survey evaluated the rate of reactivation versus recent transmission among Iranian and Afghan relapse cases. Methods The sputum specimens were digested, examined microscopically for acid-fast bacilli, and inoculated into Löwenstein-Jensen slants by standard procedures. Thereafter, the susceptibility and identification tests were performed on culture positive specimens. Subsequently, the strains that were identified as Mycobacterium tuberculosis (258 isolates) were subjected to IS6110 restriction fragment length polymorphism (RFLP) and spoligotyping. Additional patient's information was collected for further epidemiological analysis. Patients whose isolates had identical genotyping patterns were considered a cluster with recent transmission episode. Results Out of 258 available isolates, 72(28%) had multi-drug resistant (MDR-TB) in ratio and 42 (16.2%) had other resistant. Notably, 38 of MDR-TB cases (52%) were isolated from Afghan patients. By IS6110-RFLP typing method, 65 patients (25%) were clustered in 29 clusters. In cluster cases, the intra-community transmissions between Iranian and Afghan patients were 41%. All MDR-TB patients in clusters had either Haarlem I or Beijing characteristic. The risk factors like sex, family history, close contact, living condition, PPD test result and site of TB infection were not associated with clustering. Although, the MDR-TB strains were more frequent in non-cluster cases (31%) than cluster one(18%) (P < 0.05). Majority of M. tuberculosis strains isolated from non-cluster cases were belong to EAI3 (51; 30%) and CASI(32;18.6%) superfamilies. Conclusion During the studied period, reactivation of a previous infection remain the more probable cause of recurrence. Although, the evidence of intra- community transmission between Iranian and Afghan TB cases, highlighted the impact of afghan immigrants in national tuberculosis control program (NTP) of Iran.

The present study seeks to evaluate executive strategies in graduate Curriculum of Isfahan University from the point of view of management and teaching-learning strategies. This study is an applied survey. The population comprised BA students and faculty members of the University of Isfahan. In order to do so, 141 professors and 278 students were selected from among all professors and students of graduate programs in Isfahan University through stratified random sampling and proportional to the statistical population. The tool used for collecting data for this study was a researcher-made questionnaire with 25 questions scored via Likert scale. Validity of the questionnaire was ensured through content and face validity. Reliability of the test was calculated using Cronbach's alpha coefficient to be 0.94. The data collected from the questionnaires were analyzed via SPSS statistical analysis computer application in descriptive and inferential statistics level. In the descriptive statistics section, frequency, mean, standard deviation, and in the inferential statistics section, F test and single variable t test were used. Findings on teaching-learning strategies revealed that these strategies have been decently meeting the needs and expectations of students. However, they failed to meet the expectations of the students. Findings on management strategies, on the other hand, demonstrated that these strategies have not been able to meet the needs and expectations of neither professors nor students.

AbstractFrazing is a manual task in turbine blade manufacturing companies, in which the operators must discover and repair the defects of the workpieces. Such detection is so attention-demanding and time-consuming that the operators sometimes miss the defects, resulting in poor human performance and quality. Hence, this study aims to guide the operators with a systematic visual search using augmented reality (AR). For this purpose, an AR-based assistance system was built. To evaluate the system’s usability and effectiveness, a user study was conducted on 24 skilled operators. The results showed that the performance of the augmented operators was enhanced as the task completion time and detection misses decreased using the AR tool by 11.6 and 100 percent, respectively. The mental workload declined significantly after using the AR system. The most prominent finding of this research is that the AR tool was quite effective in reducing mental fatigue and workload, leading to improved human performance in ever-changing tasks. [ABSTRACT FROM AUTHOR]

This research introduces a low‐temperature catalytic‐assisted pyrolysis method for recycling waste thermosetting epoxy resins, transforming them into an efficient fire‐retardant additive for new epoxy resin formulations. In this study, we demonstrate that boric acid (BA) can significantly reduce the temperature required for epoxy resin (EP) pyrolysis, resulting in degradation products containing boron atoms that can act as a fire‐retardant additive. The impact of 5%–20% content of recycled EP (R‐EP) on the curing process, thermal stability, fire retardancy, and mechanical properties of the new EP was comprehensively investigated. The TGA results show that adding BA to epoxy resin at a 1:4 BA:EP ratio significantly reduces pyrolysis temperature. Neat EP degrades in two stages in 341°C and 557°C, while EP with BA degrades in three stages, starting below 120°C and peaking around 142°C. The results demonstrated an outstanding effect of incorporating 20% R‐EP on the char formation and fire retardancy of the new EP, surpassing the performance of 20% triphenyl phosphate (TPP), a commercially available fire retardant. The storage modulus for neat EP is 1510 MPa, increasing to 2280 MPa with EP/R‐EP 20%, indicating enhanced rigidity. Addition of R‐EP raised glass transition temperature (Tg) of the epoxy resin up to 38°C, indicating highly cross‐linked structures compared to TPP‐modified EP, which shows lower Tg values. [ABSTRACT FROM AUTHOR]

Iran's military modernization was started by Abbas Mirza, the crown prince of Fath Ali Shah. He was the pioneer of reforms in the new era of Iran. During the period of Naser al-Din Shah, these measures gained momentum. The purpose of the current research is to explain the process of modernization of Iran's military forces during the Naseri period and its relationship with security and internal-external dual obstacles to its sustainable development. This renovation started from the chancellery of Amir Kabir and continued with ups and downs until the end of the Naseri period. The main question of this research concerns why Iran's military modernization was not put on a stable path to maintain the security and protection of the whole country. The findings of the research indicate that Amir Kabir tried to enter a third country into the equation in order to gain military independence. Pursuing this policy, despite internal structural obstacles and external influence, became the source of valuable services. In the era after Amir Kabir, despite the obstacles, these programs continued. None of the Russian and British governments were satisfied with the formation of a strong military force in Iran. The clan and tribal system was in addition a serious domestic impediment for the formation of order and security in the country. Therefore, despite the formation of Kazakh and the police forces, this policy could not lead to the establishment of order and security in the country to the extent it should. [ABSTRACT FROM AUTHOR]