Runtime resource management for vision-based applications in mobile robots

Computer-vision (CV) applications are an important part of mobile robot automation, analyzing the perceived raw data from vision sensors and providing a rich amount of information on the surrounding environment. The design of a high-speed and energy-efficient CV application for a resource-constrained mobile robot, while maintaining a certain targeted level of accuracy in computation, is a challenging task. This is because such applications demand a lot of resources, e.g. computing capacity and battery energy, to run seamlessly in real time. Moreover, there is always a trade-off between accuracy, performance and energy consumption, as these factors dynamically affect each other at runtime. In this thesis, we investigate novel runtime resource management approaches to improve performance and energy efficiency of vision-based applications in mobile robots. Due to the dynamic correlation between different management objectives, such as energy consumption and execution time, both environmental and computational observations need to be dynamically updated, and the actuators are manipulated at runtime based on these observations. Algorithmic and computational parameters of a CV application (output accuracy and CPU voltage/frequency) are adjusted by measuring the key factors associated with the intensity of computations and strain on CPUs (environmental complexity and instantaneous power). Furthermore, we show how mechanical characteristics of the robot, i.e. the speed of movement in this thesis, can affect the computational behaviour. Based on this investigation, we add the speed of a robot, as an actuator, to our resource management algorithm besides the considered computational knobs (output accuracy and CPU voltage/frequency). To evaluate the proposed approach, we perform several experiments on an unmanned ground vehicle equipped with an embedded computer board and use RGB and event cameras as the vision sensors for CV applications. The obtained results show that the presented management strategy improves the performance and accuracy of vision-based applications while significantly reducing the energy consumption compared with the state-of-the-art solutions. Moreover, we demonstrate that considering simultaneously both computational and mechanical aspects in management of CV applications running on mobile robots significantly reduces the energy consumption compared with similar methods that consider these two aspects separately, oblivious to each other’s outcome

Asymptomatic cardiac rhabdomyoma in neonates : is surgery indicated?

Neonatal Tuberose sclerosis complex may be associated with symptomatic cardiac rhabdomyomas. Cardiac rhabdomyomas are the most common cardiac tumours. The symptoms include haemodynamic instability and life threatening arrhythmias usually requiring early surgical intervention. This article reports a case of a 32 week gestation newborn diagnosed with a right ventricular outflow tract mass and subsequently diagnosed with tuberose sclerosis that needed early surgical intervention.peer-reviewe

Changes in pulmonary function in patients with ulcerative colitis

SummaryObjectivesInformation on the occurrence and frequency of pulmonary involvement in patients with ulcerative colitis (UC) is inconsistent. Some authors reported pulmonary impairment with UC by standard pulmonary function tests (PFTs) and documented a reduced diffusing capacity for carbon monoxide (DLCO) especially in patients with active disease, whereas others could not detect differences in routine PFTs between UC patients and controls.AimThe aim of this prospective study was to determine the frequency and type of pulmonary dysfunction in patients with UC with respect to disease activity. Furthermore, to evaluate the influence of smoking, nutritional status, sputum cytology and sulphasalazine therapy on PFT parameters.Patients and methodsTwenty-six patients with UC (20 with active disease, 6 inactive) and 16 age and sex matched healthy controls were investigated with respect to the following pulmonary function tests, forced vital capacity (FVC), forced expiratory volume in the 1s (FEV1%) and their ratio (FEV1/FVC) and forced expiratory flow 25–75% (FEF25–75%) as well as oxygen saturation. For UC patients, colonoscopy and biopsy were done. Disease activity was assessed by Truelove index for UC. Induced sputum was sampled for cytology. Smoking habit, body mass index (BMI) and medications were recorded.ResultsFifteen out of 26 patients with UC (57.6%) exhibited at least one pathological pulmonary function test (<80% of predicted value). Small airway obstruction was reported in the 15 patients, restrictive dysfunction in 30.7% and obstructive dysfunction in 11.5%. The impairment of PFTs was significant and more pronounced in patients with active disease, FVC (−14% of predicted), FEV1 (−9% of predicted) and FEF25–75% (−32% of predicted), P<0.01, 0.05 and 0.01, respectively. There was no significant influence of smoking and medications on PFTs.ConclusionsUC patients show significantly decreased lung function tests in comparison to healthy controls. The impairment in active disease exceeded that during the remission. Early recognition is important, as they can be strikingly steroid responsive

Feasibility study of vacuum technology integrated fused deposition modeling to reduce staircase effect

Fused deposition modeling (FDM) is currently one of the most used AM technologies and has been around in various industries since its tremendous offering. Most semi-molten layered thermoplastic surface often uneven, which lead to rough and poor surface finish. The FDM process involves temperature gradient since the material extrude was in a semi-molten state. The thermal stresses present and affect the surface quality. This paper proposes an idea of using vacuum technology to reduce the “staircase effect” parts printed. The FDM machine remains in a rectangular acrylic chamber, an oil-flooded-vacuum pump connected will absorb the air inside the chamber until desire pressure while printing object. Mitutoyo SJ-301 portable surface roughness tester and optical microscope used to analyze the quality of surface finish. Result reveal with vacuum technology, improve 9% from normal print.Keywords: fused deposition modeling; simulation; vacuum technology; surface finis

Poster Session II, July 14th 2010 — Abstracts The effect of developing the explosive power and speed endurance on promoting some kinematical and physiological characteristics for 400 m hurdles runners

AbstractThe gap between the Egyptian and international records increased in 400 m hurdles race where the Egyptian record is 49.74 sec and the world record is 47.50 sec which reflects the malfunction of the training process. This pushed the researchers to perform this study to state the reasons beyond the failure of Egyptian national team players to promote and develop their levels to cope with the international levels. Pilot studies stated that fatigue is the main reason for the weak records due to performing the hurdle skipping skill repeatedly and it appears clearly before the end of the race. Fatigue helps in decreasing the efficiency of the physical and functional abilities which affects the whole performance negatively; this is why the researchers found that it is necessary to develop the explosive power and the specific endurance to help in delaying fatigue according to previous researches that tried to investigate the same problem in other races as researchers proved that the deficiency in speed and explosive power are the most important negative factors that affects the records of speed races. The experimental method was applied on 2 groups (n=16) each consisted of 8 athletes where the recommended training program was applied on the experimental group and the normal training routine was applied on the control group after taking the pre-measurements. The kinematical variables that were measured: pivoting time and distance–horizontal and vertical velocity–length of skipping step–time of race–total number of race steps–time for each 100 m in the race. The functional variables were: V O2max–blood pressure–resting and performance pulse–blood pressure–O2 pulse–lactic acid rates in blood. After applying the training program, post-measurements were taken under same conditions of the pre-measurements then proper statistical processing methods were used to analyze research variables. The most important results showed that developing the explosive power and speed endurance had a positive effect on developing the numerical records due to promoting the kinematical and physiological characteristics of the research sample with a percentage of 38% for kinematical variables and 24% for physiological variables. This is why the researchers recommended that applying similar programs on 400 m hurdles runners is necessary to develop their kinematical and functional abilities. Also further studies should be performed to help in developing numerical records for other races

Vacuum fused deposition modelling system to improve tensile strength of 3D printed parts

Functional parts require high a level of strength and the current Fused Deposition Modelling (FDM) cannot be fully utilized as the end used parts. The poor mechanical strength is caused by the incomplete layer bonding during the printing process. In the printing process, the interlayer bonding is made too quick thus the layers are not fully fused together causing the reduced tensile strength. This paper presents a possible solution to this problem by incorporating vacuum technology in FDM system to improve tensile strength of 3D printed specimens. In this study, a desktop FDM machine was placed and operated inside a low pressure vacuum chamber. The results obtained show an improvement of 12.83 % of tensile strength compared to the standard specimen. This paper concludes that the low pressure environment is useful in reducing the heat loss due to convection of air, hence directly improves the specimen’s tensile strength.Keywords: additive manufacturing; fused deposition modelling; vacuum system; mechanical strength

Forage yield of some grasses in monoculture and their mixtures with legumes under irrigation in central Sudan

&nbsp;&nbsp;&nbsp; Mixed cropping system provides forage of higher yield than monoculture. This study was conducted during autumn, summer and winter seasons of 2014/15 and 2015/16 at the experimental farm of the Faculty of Agricultural Sciences, University of Gezira, Wad Medani, Sudan. The objective of this study was to investigate the effects of monoculture of selected grasses and their mixtures with selected legumes on their fresh forage yield under irrigation in central Sudan. The experimental material consisted of three grasses, namely; Sudan grass (SG), maize (MZ) and Abu70 and three legumes, cowpea (CP), black-eyed bean (BB) and lablab bean (LB). Grasses were grown in pure stand or mixed with legumes in 1:1 and 2:1 ratios. The results showed that mixing significantly increased growth parameters during all seasons. The highest fresh forage yield of grasses was obtained by the mixture compared with monocultures. Land equivalent ratio exceeded 1.0 in all seasons which indicated clearly the advantage of mixtures over monocultures. Based on the results of this study, to obtain high forage yield of grasses, it was recommended to use seed combinations of 40 kg/ha MZ + 20 kg /ha LB, 40 kg /ha SG+ 20 kg /ha CP and 40 kg /ha SG + 20 kg /ha LB during autumn, summer and winter seasons, respectively. &nbsp; &nbsp;&nbsp;&nbsp; يؤدي الخلط إلى زيادة في إنتاجية العلف. أجريت هذه الدراسة خلال صيف و خريف وشتاء 2014/15 و2015/16 بالمزرعة التجريبية، كلية العلوم الزراعية، جامعة الجزيرة، السودان. تهدف هذه الدراسة لتقييم أثر الخلط علي إنتاجية العلف لبعض الحشائش النجيلية ومخاليطها بالبقوليات تحت ظروف الري في أواسط السودان. تضمنت الدراسة ثلاثة محاصيل نجيلية هي حشيشة السودان وأبوسبعين والذرة الشامية وثلاثة محاصيل بقولية هي اللوبيا الحلو واللوبيا البيضاء واللوبيا العفن. زرعت المحاصيل النجيلية منفرده وفي مخاليط بنسبة&nbsp; 1:1و1:2 أظهرت نتائج التحليل أن كل من الإنتاج ومكوناته قد زادت زيادة معنوية كنتاج للخلط. تحققت الإنتاجية العالية للعلف الأخضر عند زراعة الاعلاف النجيلية في مخاليط مقارنة بزراعتها منفرده. قيم نسبة مكافئ الأرض فاقت الواحد الصحيح (1.0) خلال كافة المواسم مما يؤكد تفوق نظام الخلط علي زراعة المحصول نقيا. بناء علي نتائج هذه الدراسة ولتحقيق إنتاجية أعلاف نجيلية عالية نوصي بزراعتها في مخاليط بنسبة 40 كجم بذور/هكتار ذرة شامية + 20 كجم بذور/هكتار لوبيا عفن و 40 كجم بذور/هكتار حشيشة السودان + 20 كجم بذور/هكتار لوبيا حلو و 40 كجم بذور/هكتار حشيشة السودان + 20 كجم بذور/هكتار لوبيا عفن خلال مواسم الخريف والصيف والشتاء على التوالي. &nbsp; &nbsp; &nbsp; &nbsp; &nbsp

Forage yield of some legumes in monoculture and mixtures under irrigation in central Sudan

&nbsp;&nbsp;&nbsp; The study was conducted during summer, autumn and winter seasons of 2014/15 and 2015/16 at the experimental farm of the Faculty of Agricultural Sciences, University of Gezira, Wad Medani, Sudan, to investigate the effect of mixing on forage yield of selected three legumes namely: cowpea (CP), black-eyed bean (BB) and lablab bean (LB) and their mixtures with three selected grasses, Sudan grass (SG), maize (MZ) and forage sorghum (Abu70). Legumes were grown in pure stand and mixed with grasses in 1:1 and 1:2 ratios. Treatment combinations were arranged in a randomized complete block design (RCBD) with four replications. The results showed that mixing significantly increased plant fresh weight, LAI, and fresh forage yield during most seasons and decreased number of branches per plant during different seasons. Land equivalent ratio mostly was greater than one. Based on the results of this study to obtain high forage yield, it was recommended to use seed combinations of 30 kg seeds/ha LB + 30 kg seed/ha MZ during autumn and winter and 30 kg seeds/ha BB + 30 kg seed/ha SG during summer season. &nbsp;&nbsp;&nbsp; نفذت هذه الدراسة خلال صيف، خريف وشتاء 2014/2015 و2015/2016 بالمزرعة التجريبية لكلية العلوم الزراعية، جامعة الجزيرة، السودان. تهدف هذه الدراسة لتقييم أثر الخلط علي إنتاجية المحاصيل البقولية المختارة وهي اللوبيا الحلو واللوبيا البيضاء واللوبيا العفن ومخاليطها مع المحاصيل النجيلية حشيشة السودان، أبوسبعين والذرة الشامية تحت ظروف الري في أواسط السودان. زرعت المحاصيل البقولية منفرده وفي مخاليط بنسبة 1 : 1 و 1 : 2. تم استخدام تصميم القطاعات العشوائية الكاملة بأربعة مكررات. الخلط أدى إلى زيادة معنوية لكل من&nbsp; وزن النبات الرطب، دليل مساحة الأوراق وإنتاجية العلف الأخضر خلال معظم المواسم بينما أدى الخلط إلى نقصان عدد الأفرع في مختلف المواسم. كانت قيم نسبة مكافئ الأرض في أغلب المواسم&nbsp; أعلى من الواحد الصحيح. بناءً على نتائج هذه الدراسة ولتحقيق إنتاجية أعلاف عالية نوصي بزراعة المحاصيل البقولية في مخاليط بنسبة خلط 30 كجم بذور/هكتار لوبيا عفن + 30 كجم بذور/هكتار ذرة شامية خلال فصلي الخريف والشتاء وبنسبة 30 كجم بذور/هكتار لوبيا حلو + 30 كجم بذور/هكتار حشيشة السودان خلال فصل الصيف. &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp