1,398 research outputs found
An Underwater Vehicle Navigation System Using Acoustic and Inertial Sensors
Unmanned Underwater Vehicles (UUVs) have become an essential tool for different underwater tasks. Compared with other unmanned systems, the navigation and localization for UUVs are particularly challenging due to the unavailability of Global Positioning System (GPS) signals underwater and the complexity of the unstable environment. Alternative methods such as acoustic positioning systems, Inertial Navigation Systems (INS), and the geophysical navigation approach are used for UUV navigation. Acoustic positioning systems utilize the characteristics of acoustic signals that have a lower absorption rate and a more extended propagation distance than electromagnetic signals underwater. The significant disadvantage of the INS is the “drift,” the unbounded error growth over time in the outputs. This thesis is aimed to study and test a combined UUV navigation system that fuses measurements from the INS, Doppler Velocity Log (DVL), and Short Baseline (SBL) acoustic positioning system to reduce the drift. Two Kalman filters are used to do the fusion: the Extended Kalman Filter (EKF) and the Unscented Kalman Filter (UKF). After conducting the experiments and simulation, the results illustrated the INS/SBL fusion navigation approach was able to reduce the drift problems in the INS. Moreover, UKF showed a better performance than the EKF in the INS
SMANJENJE TROŠKOVA TRANSPORTA OTPADA U PROVINCIJI TAIF, SAUDIJSKA ARABIJA
Municipal solid waste (MSW) management is a critical issue in the Kingdom of Saudi Arabia (KSA). Management of solid waste in crowded conditions, especially in main cities such as the Al-Taif Province. This paper deals with that case study and focuses on how to solve material handling problems by applying conventional methods and computer ability. One of the costliest operations in the civil sector is transportation for material handling. City mayors considered transportation and materials handling as a subclass of the linear programming technique, thus linear programming problems take into consideration that the main objective is to handle materials from the city centre site to the identified dumping area. There are many methods and tools used to solve the transportation problem (TP) to find out the maximum or minimum in order to reduce cost or maximize profit. The methods related to manual solutions and others used many different computer applications. Manual solutions include the northwest corner method, the minimum cost method, the row minimum cost method, the column minimum cost method, and Vogel\u27s approximation method, and computer applications such as LINGO, Lingo, and solver function using Microsoft Excel. This case study focuses on applying the Microsoft Excel function to find the minimum cost of the transportation system in waste materials to reduce the transportation cost from the city centre to the final destination (dumping area) to be used. The results achieved with the model aided in obtaining optimal solutions and finally, the optimal solutions were checked.Gospodarenje čvrstim komunalnim otpadom kritično je pitanje u Kraljevini Saudijskoj Arabiji (KSA), posebice u uvjetima guste naseljenosti u glavnim gradovima i pokrajinama kao što je Taif. Ovaj rad prikazuje studiju slučaja i usredotočen je na to kako riješiti probleme gospodarenja i manipulacije materijalima primjenom konvencionalnih metoda i informatičkom tehnologijom. Jedan od najskupljih poslova u komunalnome sektoru jest transport materijala. Gradske uprave transport i rukovanje materijalima smatraju potklasom tehnologije linearnoga programiranja, stoga problemi linearnoga programiranja uzimaju u obzir da je glavni cilj rukovanje materijalima od središta grada do identificiranoga odlagališta. Postoje mnoge metode i alati koji se koriste za rješavanje problema transporta (TP) kako bi se saznao maksimum ili minimum u smislu smanjenja troškova ili maksimiziranja profita. Te metode primarno su se odnosile na manualna rješenja, a druge su se koristile mnogim različitim računalnim aplikacijama. Manualna rješenja uključuju metodu sjeverozapadnoga kuta (northwest corner method), metodu minimalnoga troška, metodu minimalnoga troška retka, metodu minimalnoga troška stupca i Vogelovu metodu aproksimacije te računalne aplikacije kao što su LINGO, Lingo i funkciju Solver koja je uključena u Microsoft Excel. Ova studija slučaja usredotočuje se na primjenu Microsoft Excel funkcije za pronalaženje minimalne cijene sustava transporta otpadnoga materijala kako bi se smanjio trošak transporta od centra grada do konačnoga odredišta (odlagalište). Rezultati dobiveni modeliranjem dali su optimalna rješenja koja su na kraju rada i provjerena
Detection of mine roof failure using inexpensive LiDAR technology
Slope, Roof, and mine wall stability problems are some of the main reasons for deaths at U.S. surface or underground mining. The safety instruments were not enough to prevent that failure or even predict it before it occurs. However, the cost of such a tool that can be helpful in detecting roof failures is very high and not reachable in most instances.
The present study investigates the feasibility of using the M16 Leddar Evaluation Kit to detect the roof failure in mines. The M16 Leddar Evaluation kit cost is between 300, so it is the reachable price if it provides the required safety in mines. In fact, the underground mines have many openings, so the needs for instruments that can be distributed in all tunnels and safe all workers are urgent. The Leica Scan Station P40-3D Laser Scanner costs $123915.00, so in mine industry, it is not worthy to establish the mining with such high cost like that. Buying one unit of the Leica ScanStation P40-3D Laser Scanner to provide the safety and minimize the expenses in the mining industry is not a practical idea which is providing safety to some of the workers in one tunnel spot and neglect the others.
Steel movement plate has been built and attached to a linear actuator that can move with a resolution around 0.00375 mm per step and stroke 50 mm in order to simulate the roof failures in mines. It is not possible to try the M16 in real mine due to the time limits and absence of not unstable mines locally, besides the intention that the author has to start with an office environment.
The M16 Leddar Evaluation kit is aimed directly to movement plate and collecting the deformation derived by the actuator. The results collected has many of anomalies and irregular data that can be eliminated by doing some of the statistical identification of outliers.
The results show that the M16 Leddar evaluation kit is capable of detecting the movement plate profile with a precision between 0.1 mm and 3 mm per integration period --Abstract, page iii
Petroleum Hydrocarbon and Living Organisms
Living matters are inadvertently exposed to the highly toxic petroleum hydrocarbon (PH) byproducts. Despite the fact that petroleum-related industry is globally thriving, the health hazard of most hydrocarbons is not well characterized. In human, organs and, sometimes, whole systems such as the nervous system, respiratory, circulatory, immune, reproductive, and endocrine systems are susceptible to PHs depending on the level of exposure. Marine organisms are known to be affected by PHs in various stages. Impacts from lethal to sub-lethal dose of PHs range from habitat destruction, mass mortality, and impaired physiological functions such as reduced feeding, slow growth and development, respiration problems, loss of locomotion, balance, and swimming ability. Bioaccumulation of toxic PHs in food chains in marine environment can be retained for decades and affect plants, animals, and eventually human. This chapter summarizes the PHs toxic effects on living organisms and the potential mechanisms of action based on epidemiological studies
EFL Learners’ Knowledge and Use of Gender Stereotypes: Evidence from Arabic Native Speakers
The research explored EFL learners’ knowledge and use of gender stereotypes of common English nouns (e.g., doctor and nurse). In the study, we compared how EFL learners living in Saudi Arabia and native English speakers rated 24 nouns that can be used to refer to either males or females and how they interpreted sentences containing the gender-specific pronouns his and her preceded by one of the three types of these nouns (i.e., male stereotyped, female stereotyped, or gender neutral). The results showed that performance for EFL learners differed from native speakers’ in both tasks. EFL learners rated nouns as generally referring to males more often than did native English speakers. EFL learners were also significantly less likely to interpret her and his as referring to the preceding noun than were native English speakers. The results suggest that in EFL courses, learners are likely to benefit from explicit coverage of gender ambiguous English nouns and the topic of gender stereotyping as an important aspect of vocabulary knowledge
Towards Measuring Learning Effectiveness considering Presence, Engagement and Immersion in a Mixed and Augmented Reality Learning Environment
The current era of advanced display technologies, such as a head mounted displays, smart glasses and handheld devices, have supported the usage of mixed-reality and augmented reality concepts in smart educational classrooms. These advanced technologies have enabled enhanced collaboration and an interactive communication between distance learners and local learners. Being present' is a key factor in both worlds (real and virtual) as it plays an important role in increasing the students' collaborative engagement during the learning activity. However, few studies have considered how much using such immersive interfaces with various learning scenarios may ultimately affect learning outcomes, and whether students feel fully engaged or not in such environments. This work-in-progress paper will demonstrate a MiRTLE+ prototype of how remote students can collaborate within mixed-reality environments by using an augmented reality approach. Secondly, it will explore the learning effectiveness based on the following factors: students' presence, engagement, and immersion in smart environments. With regard to the learning task, we will consider a card game task to measure the learners' progress as they progress from novice to expert player. To evaluate these factors, we utilise several existing frameworks which have been applied to our mixed-reality worlds that help us to examine the learning outcomes from using these environments
Fostering the Professional Development of Saudi Female Students: Implications for Educators in Apparel and Textiles Programs in Saudi Arabia
The purpose of this study was to identify the skills and knowledge needed for Saudi women to succeed in the apparel retail industry (ARI). This study is essential to develop an apparel merchandising (AM) program for the apparel and textiles (AT) discipline in Saudi Arabia. It is important to prepare Saudi women for new careers in the apparel industry and provide alternative options for apparel and textiles students to choose from besides apparel design and textile science
Systemic Review and Clinical Management in Diagnosis and Treatment of the Iron Deficiency Anemia in Adults
This study aimed at exploring with a systematic review the clinical management in diagnosis and treatment of the iron deficiency anemia in adults, as the iron deficiency is the most frequent cause of anemia worldwide. And it impairs quality of life, increases asthenia and can lead to clinical worsening of patients. In addition, iron deficiency has a complex mechanism whose pathologic pathway is recently becoming better understood. This review summarizes the current knowledge regarding diagnostic algorithms for iron deficiency anemia. The majority of aetiologies occur in the digestive tract, and justify morphological examination of the gut. First line investigations are upper gastrointestinal endoscopy and colonoscopy, and when negative, the small bowel should be explored; newer tools such as video capsule endoscopy have also been developed. The treatment of iron deficiency is aetiological if possible and iron supplementation whether in oral or in parenteral form
Developing an ESP-Based Language Learning Environment to Help Students Improve Critical Thinking Skills in Written Output
In recent years, as a result of both research discoveries in the fields of foreign language acquisition and learning, the concept of teaching and learning has undergone a significant transformation. English for Specific Purposes (ESP) is a learner-centered approach to teaching English as a foreign language that emphasizes developing communicative proficiency in niche industries such agronomy, commerce, academia, accountancy, education, engineering, and information technology. This concept of English-for-Teaching as a restricted form of ESP for the classroom builds on the knowledge that instructors already have about teaching while also introducing and validating specific classroom terminology. When students interact and cooperate with one another, ESP practice emerges naturally in a language learning setting. Two major aspects that ESP highlights are the growth of dialogical interaction and the establishment of ecologically complete learning environments. In this essay, we create an ESP to aid students in the development of their critical thinking (CT) abilities in written output. We combine the Synergy model, Brain-based learning, and the Flipped Classroom models to create an ESP environment. Students CT abilities and academic success served as the studys criteria. The Course Satisfaction Questionnaire and placement exams were used to obtain the statistical data. Using the Cronbach Alpha coefficient (CAC) and Spearman correlation coefficient, the test on CT data was interpreted, and the combined data was examined using SPSS (V 26.0). By immersing students in problem-solving- based learning (PBL), this paradigm helps students develop their CT skills. It also helps students achieve academically by elevating their sense of accountability for learning outcomes and promoting the use of a variety of learning strategies
Predictors of Student Success in an Entry-Level Baccalaureate Dental Hygiene Program
PURPOSE: The purpose of this study was to measure the utility of various predictors used by the Old Dominion University Gene W. Hirschfeld School of Dental Hygiene baccalaureate degree dental hygiene program in selecting dental hygiene students who are most likely to graduate and be successful in passing the National Board Dental Hygiene Examination (NBDHE). The following factors were examined: grade point average (GPA); science GPA; final grade in various prerequisite courses; final grade in first-year dental hygiene courses; academic setting where prerequisite courses were completed; multiple attempts to achieve a passing course grade; and admissions criteria points (ACP).
METHODS: The sample selected for study consisted of the academic records of dental hygiene students admitted to the program from 1998 to 2002 (n = 235), who would have been eligible to take the NBDHE from 2000 to 2004. Data were analyzed using multiple logistic regression to determine success as measured by graduation (n = 146). With NBDHE as the criterion variable, data were analyzed using the multiple linear regression to determine successful entry into the profession (n = 130); significance was predetermined at the 0.05 level.
RESULTS: Data analysis revealed that final course grade in oral pathology was a significant predictor of successful graduation (P = 0.0008). Variables that predicted NBDHE success were final course grade in oral pathology, final course grade in oral anatomy and histology, and the ACP rating (P \u3c .0001, P \u3c .0001, and P = .0245, respectively). There was no statistically significant relationship for other variables.
CONCLUSION: Final grades in oral pathology and oral anatomy and histology can significantly predict graduation and NBDHE success at this institution, suggesting that educators look to improving student performance after admission to the program to improve the likelihood of success. Additionally, when this institution\u27s admission variables were combined into a cluster of variables (ACP), they proved significant at predicting success
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