Multimodal hybrid powerplant for unmanned aerial systems (UAS) robotics

Most UAS propulsion systems currently utilize either Internal Combustion Engines (ICE) or Electric Motor (EM) prime movers. ICE are favoured for aircraft use due to the superior energy density of fuel compared to batteries required for EM, however EM have several significant advantages. A major advantage of EM is that they are inherently self starting have predictable response characteristics and well developed electronic control systems. EMs are thus very easy to adapt to automatic control, whereas ICE have more complex control response and an auxiliary starting motor is required for automated starting. This paper presents a technique for determining the performance, feasibility and effectiveness of powerplant hybridisation for small UAS. A Hybrid Powerplant offers the possibility of a radical improvement in the autonomy of the aircraft for various tasks without sacrificing payload range or endurance capability. In this work a prototype Aircraft Hybrid Powerplant (AHP) was designed, constructed and tested. It is shown that an additional 35% continuous thrust power can be supplied from the hybrid system with an overall weight penalty of 5%, for a given UAS. Dynamometer and windtunnel results were obtained to validate theoretical propulsion load curves. Using measured powerplant data and an assumed baseline airframe performance characteristic, theoretical endurance comparisons between hybrid and non-hybrid powerplants were determined. A flight dynamic model for the AHP was developed and validated for the purposes of operational scenario analysis. Through this simulation it is shown that climb rates can be improved by 56% and endurance increased by 13%. The advantages of implementing a hybrid powerplant have been baselined in terms of payload range and endurance. Having satisfied these parameters, a whole new set of operational possibilities arises which cannot be performed by non-self-starting ICE only powered aircraft. A variety of autonomous robotic aircraft tasks enabled by the hybrid powerplant is discussed

Dissecting and refining the staging of chronic kidney disease

The current Kidney Disease Outcomes Quality Initiative (KDOQI) staging system of chronic kidney disease (CKD) is simple but too rigid to accommodate variations in renal function observed in the general population. The formula most commonly used to estimate renal function is not validated in subjects without a priori evidence of renal disease. Their combined use results in inappropriate diagnosis of CKD and improbable estimates of prevalence rates. Although this initiative has raised the profile of kidney disease, the exaggeration of the scope of the problem could distract nephrologists from their specialist role. The nephrology community needs a revised staging system for CKD that allows accurate, effective, and timely communication with patients, primary care doctors, public health physicians, and policy makers. Its single most important function will be to identify those patients who will benefit from targeted screening and effective and safe interventions. We offer for discussion a modified definition and staging system of CKD based on the presence of unequivocal, irreversible structural kidney disease, the presence or degree of impairment of kidney function, and the consequences thereof

IgA nephropathy at two score and one

On May 26–28, 2009, an international symposium on IgA nephropathy was convened in Stresa, Italy, as a Satellite Symposium of the World Congress of Nephrology held in Milan. This meeting was attended by a large number of scientists and clinicians working in the field of IgA nephropathy. The oral and poster presentations (over 70) ranged from very fundamental structural biology to clinical management. This article attempts to summarize the main findings of the meeting and to put forth some new perspectives and hypotheses regarding human IgA nephropathy on the 41st anniversary of its original description by Berger and Hinglais in 1968

A Study of Four-Mallet Grips Used in Playing Keyboard Percussion Instruments

The purpose of this study was to evaluate the efficiency of three common grips used in four-mallet playing. The three grips were referred to as (a) the Musser grip, (b) the cross stick grip No. 1, and (c) the cross stick grip No. 2. A thorough description (including illustrations) was given for each grip. The evaluation of efficiency was made through research testing, which was conducted by the author. Forty individuals participated in the research testing. Four tests were conducted, and each test had ten participants. The individuals who participated in Tests I, II and III had no previous four-mallet experience. The individuals who participated in Test IV had previous four-mallet experience. The evaluation of the efficiency covered by the four tests was limited to (a) horizontal movement of the outside mallet(s), (b) horizontal movement of the inside mallet(s), and (c) horizontal movement of the hand (s). According to Tests I, II and III, the majority of beginning four-mallet players will find the cross stick grip No. 2 the easiest and most efficient (as far as the three movements which were tested are concerned) of the three grips. However, some individuals (a much smaller percentage) will prefer either the Musser grip or the cross stick grip No. 1. Many beginners will find the Musser grip extremely difficult. A very small percentage of beginning four-mallet students will have poor efficiency using cross stick grip No. 2. According to the results of Test IV, the efficiency of the Musser grip and the cross stick grip No. 2 improve at a faster rate than does the efficiency of the cross stick grip No. 1. The movements tested in this study are extremely important when playing with four mallets. However, this study was limited to the testing of three types of horizontal movements and, therefore, did not cover all the aspects of four-mallet playing. Because all factors were not included in this study, no one grip was proven to be ultimately the "'best." Each individual four-mallet player must decide for himself which grip is best suited for his particular needs. The findings of this study should aid in making that decision

Presenting Information About White Privilege and Systemic Racism: Message vs. Messenger

In our study, we found evidence for some effect on how students perceive information about systemic racism and White privilege based on the perceived identity of the presenter

How Students View Diversity in Their Education: A Qualitative Examination

In this study, we examined students’ open responses to questions regarding their opinions about diversity on their college campus. Here, we report on responses about age, religion, and political views in the classroom and outside the classroom

Hybrid electric propulsion systems for skydiving aircraft

• Show viability of hybrid electric and all-electric aircraft concept for skydiving missions. • Push forward, investment in new electrical propulsion technology equipped light commuter category aircraft