Performance, emissions, and physical characteristics of a rotating combustion aircraft engine, supplement A

Testing was conducted using the basic RC2-75 engine, to which several modifications were incorporated which were designed to reduce the hydrocarbon emissions and reduce the specific fuel consumption. The modifications included close-in surface gap spark plugs, increased compression ratio rotors, and provisions for utilizing either side or peripheral intake ports, or a combination of the two if required. The proposed EPA emissions requirements were met using the normal peripheral porting. The specific fuel economy demonstrated for the modified RC2-75 was 283 g/kW-hr at 75% power and 101 brake mean effective pressure (BMEP) and 272.5 g/kW-hr at 75% power and 111 BMEP. The latter would result from rating the engine for takeoff at 285 hp and 5500 rpm, instead of 6000 rpm

Phenomena of Cathode Sputtering

When metal is deposited cathodically upon a glass plate a film is found upon the side of the plate away from the cathode. In the study of this deposit both alternating and direct potentials were employed. An attempt to increase the deposit by various reflecting surfaces gave negative results. A possible explanation of the phenomenon is offered, based upon the assumption that the metallic particles receive a positive charge after leaving the cathode. An attempt to sputter non-conductors in the form of metallic oxides gave negative results

The effects of smoking cessation on control of food intake in postmenopausal African-American and Caucasian women

Smoking cessation leads to greater weight gain in women than men, and older and postmenopausal women are at greater risk for weight gain than younger, premenopausal women. African-American postmenopausal women may be at the greatest risk. Weight gain after smoking cessation is primarily due to increased caloric intake. Currently, the literature regarding measurement of macronutrient intake after smoking cessation is plagued with methodological problems. The Geiselman Macronutrient Self-Selection Paradigm (MSSP) significantly and systematically varies fat across other macronutrients and the Geiselman Food Preference Questionnaire (FPQ) measures the negative feedback of satiation via pre- and postprandial hedonic ratings of foods. Fifty-five Caucasian and 32 African-American postmenopausal women were recruited for the present study. We measured changes in total caloric intake, and specific macronutrient intake with the use of the MSSP, and we measured hedonic ratings with the use of the FPQ before and after smoking cessation. We hypothesized that total caloric intake and intake of high-fat foods would increase postcessation. Also, we hypothesized that women would be able to reach satiation more readily while smoking than they would postcessation. We found that Caucasian females increased total caloric intake and intake of high-fat foods after smoking cessation; however, their level of satiation did not change from pre- to postcessation. Thus, the Caucasian women had to ingest significantly more total kcals, especially from high-fat foods, postcessation to achieve the same level of satiation that they reached with much smaller amount of food while still smoking. Total caloric intake, including intake of high-fat foods, did not differ from pre- to postcessation in African-American females. African-American women ingested significantly more total kcals and intake of high-fat foods than did Caucasian females, regardless of smoking status. African-American women also showed significantly smaller decreases in hedonic ratings of high-fat foods from pre- to postprandial than did Caucasian women, indicating less satiating effect of high-fat foods in the African-American females

Validated novel software to measure the conspicuity index of lesions in DICOM images

Description of purpose A novel software programme and associated Excel spreadsheet has been developed to provide an objective measure of the expected visual detectability of focal abnormalities within DICOM images. Methodology ROIs are drawn around the abnormality, the software then fits the lesion using a least squares method to recognise the edges of the lesion based on the full width half maximum. 180 line profiles are then plotted around the lesion, giving 360 edge profiles. The co-ordinates show in Figure 1 are captured, as well the standard deviation of the pixel values within the background and lesion (representing anatomical noise and lesion noise respectively). An Excel spreadsheet has been developed to allow variables to be calculated, including SNR and CNR. A conspicuity index has also been developed: Results The software has been validated using the GAMMEX ACR CT accreditation phantom, varying mA, kVp and slice thickness (ST) and the results have been found to give a linear response: Conclusion A novel software programme has been validated to allow calculation of many physical properties of lesions. Additionally, a new measure of conspicuity index has been developed for focal lesions. The analysis could be further developed to incorporate reader decision-analysis data and eye-tracking data allowing correlations between physical and perception measures to be made beyond basic CNR calculations. It could also be used as a tool to distinguish between perceptual and cognitive error. Further refinements could lead to measures of the detectability of more diffuse disease features

Topological entropy and blocking cost for geodesics in riemannian manifolds

For a pair of points $x,y$ in a compact, riemannian manifold $M$ let $n_t(x,y)$ (resp. $s_t(x,y)$) be the number of geodesic segments with length $\leq t$ joining these points (resp. the minimal number of point obstacles needed to block them). We study relationships between the growth rates of $n_t(x,y)$ and $s_t(x,y)$ as $t\to\infty$. We derive lower bounds on $s_t(x,y)$ in terms of the topological entropy $h(M)$ and its fundamental group. This strengthens the results of Burns-Gutkin \cite{BG06} and Lafont-Schmidt \cite{LS}. For instance, by \cite{BG06,LS}, $h(M)>0$ implies that $s$ is unbounded; we show that $s$ grows exponentially, with the rate at least $h(M)/2$.Comment: 13 page

Exploratory Analysis of Highly Heterogeneous Document Collections

We present an effective multifaceted system for exploratory analysis of highly heterogeneous document collections. Our system is based on intelligently tagging individual documents in a purely automated fashion and exploiting these tags in a powerful faceted browsing framework. Tagging strategies employed include both unsupervised and supervised approaches based on machine learning and natural language processing. As one of our key tagging strategies, we introduce the KERA algorithm (Keyword Extraction for Reports and Articles). KERA extracts topic-representative terms from individual documents in a purely unsupervised fashion and is revealed to be significantly more effective than state-of-the-art methods. Finally, we evaluate our system in its ability to help users locate documents pertaining to military critical technologies buried deep in a large heterogeneous sea of information.Comment: 9 pages; KDD 2013: 19th ACM SIGKDD Conference on Knowledge Discovery and Data Minin