Preliminary design-lift/cruise fan research and technology airplane flight control system

This report presents the preliminary design of a stability augmentation system for a NASA V/STOL research and technology airplane. This stability augmentation system is postulated as the simplest system that meets handling qualities levels for research and technology missions flown by NASA test pilots. The airplane studied in this report is a T-39 fitted with tilting lift/cruise fan nacelles and a nose fan. The propulsion system features a shaft interconnecting the three variable pitch fans and three power plants. The mathematical modeling is based on pre-wind tunnel test estimated data. The selected stability augmentation system uses variable gains scheduled with airspeed. Failure analysis of the system illustrates the benign effect of engine failure. Airplane rate sensor failure must be solved with redundancy

Testing the Predictions of Surprisal Theory in 11 Languages

A fundamental result in psycholinguistics is that less predictable words take a longer time to process. One theoretical explanation for this finding is Surprisal Theory (Hale, 2001; Levy, 2008), which quantifies a word's predictability as its surprisal, i.e. its negative log-probability given a context. While evidence supporting the predictions of Surprisal Theory have been replicated widely, most have focused on a very narrow slice of data: native English speakers reading English texts. Indeed, no comprehensive multilingual analysis exists. We address this gap in the current literature by investigating the relationship between surprisal and reading times in eleven different languages, distributed across five language families. Deriving estimates from language models trained on monolingual and multilingual corpora, we test three predictions associated with surprisal theory: (i) whether surprisal is predictive of reading times; (ii) whether expected surprisal, i.e. contextual entropy, is predictive of reading times; (iii) and whether the linking function between surprisal and reading times is linear. We find that all three predictions are borne out crosslinguistically. By focusing on a more diverse set of languages, we argue that these results offer the most robust link to-date between information theory and incremental language processing across languages.Comment: This is a pre-MIT Press publication version of the pape

Design definition study of a NASA/Navy lift/cruise fan technology V/STOL airplane: Risk assessment addendum to the final report

An assessment of risk, in terms of delivery delays, cost overrun, and performance achievement, associated with the V/STOL technology airplane is presented. The risk is discussed in terms of weight, structure, aerodynamics, propulsion, mechanical drive, and flight controls. The analysis ensures that risks associated with the design and development of the airplane will be eliminated in the course of the program and a useful technology airplane that meets the predicted cost, schedule, and performance can be produced

Robust texture features for still-image retrieval

A detailed evaluation of the use of texture features in a query-by-example approach to image retrieval is presented. Three radically different texture feature types motivated by i) statistical, ii) psychological and iii) signal processing points of view are used. The features were evaluated and tuned on retrieval tasks from the Corel collection and then evaluated and tested on the TRECVID 2003 and ImageCLEF 2004 collections. For the latter two the effects of combining texture features with a colour feature were studied. Texture features that perform particularly well are identified, demonstrating that they provide robust performance across a range of datasets

THE IMPORTANCE OF CONGENITAL MALFORMATIONS AT BIRTH

Introduction: Countries that have overcome high infant mortality rates show, nowadays, concentration of deaths in the neonatal period and, within it, mainly in the first week of life (early neonatal deaths). Regarding causes of death, as some diseases have started to be controlled, a significant proportional increase in the participation of congenital malformations has been verified. Objective: To describe the prevalence of congenital malformations (CM) at birth in conceptuses (stillbirths and live births) of women hospitalized in institutions located in the city of São Paulo, Brazil. Methods: Descriptive, cross-sectional study carried out at 4 hospitals in the city of São Paulo during 3 months in the 2 and semester of 2011. Data were collected by means of interviews with the women and examinations of hospital records. The CM were studied according to variables of epidemiological and socio-demographic interest. The deaths were analyzed according to underlying and associated causes. Results: The results showed the occurrence of 9.1% of CM registered among stillbirths and 4.3% among live births. Among the latter – 238 newborns – 284 CM were registered, totaling 1.2 CM per live birth with CM registered. Among the 238 newborns that had a CM register, there were 10 deaths by CM (4.2%). This value differs from the one verified among the live births without CM register that died (19 out of 5,341 or 0.4%). Aiming to identify possible  occurrences of death after hospital discharge, a linkage was performed between the official mortality database of the city of São Paulo and the study’s database. The occurrence of 18 deaths was found in this way, 4 of which were caused by CM. Thus, the total of deaths in the 1 st year of life was 47, and 14 of them had CM as the underlying cause, which leads to a proportional infant mortality by CM equal to 29.8% and an infant mortality coefficient by CM of 2.5%o live births. The data show a high undercount of CM in the registers of the official information systems (regarding SINASC, the prevalence of CM in the study was three times the prevalence for the city of São Paulo and 5.4 times the prevalence for Brazil). Conclusion: It is necessary to implement measures to improve the register of CM in the information systems, such as: raising doctors’ awareness concerning the importance of diagnosing CM and registering it in the newborn’s hospital records, creating a specific space to register the CM in the newborn’s hospital records, and qualifying and monitoring the personnel in charge of filling in the Certificate of Live Birth and transcribing it to the information systems

Análise dos registros de nascimentos vivos em localidade urbana no Sul do Brasil

Foram analisados os nascimentos vivos de mulheres residentes em Londrina, Paraná, (Brasil), ocorridos entre abril e setembro de 1994 (4259), a partir das duas vias das Declarações de Nascidos Vivos (DN) - vias brancas (provindas dos hospitais onde ocorreram os nascimentos) e amarelas (vindas dos Cartórios onde houve o registro) - recebidas pelo Serviço Municipal de Saúde. Visitas domiciliárias foram realizadas nos casos em que não houve o pareamento das respectivas vias da DN de cada criança (possível caso de sub-registro ou parto domiciliar). A taxa de sub-registro de nascimento vivo foi estimada entre 5,3% e 6,6%; o custo foi o principal motivo alegado para o não registro, seguido da negligência e legitimidade. Dos que foram registrados, em 88,7% o mesmo ocorreu até 60 dias após o parto e o tempo médio para o registro foi de 26,5 dias (com desvio-padrão de 52 dias).Variáveis estatisticamente associadas aos fatos de registrar e ter sido no tempo legal (60 dias) foram tipo de parto, instrução e idade materna. Estimativa da proporção de partos domiciliares entre os nascimentos registrados foi um valor entre 0,1 e 0,3%, sendo as razões alegadas: "opção por parte da mãe", "falta de condução para ser removida para o hospital" e "não deu tempo de chegar no hospital".Live births which occurred in the period from April to September of 1994 were analysed, using the two copies of the Birth Declaration-BD-( the white copy coming from the hospital where the child was born and the yellow copy sent by the Legal Registry Office where the birth was registered) received by the Londrina Municipal Health Service. After the "cross matching"of both copies (for each child), household interviews were performed in cases without matched pairs (only a white or only a yellow copy indicating possibly unregistered or home deliveries). Results showed that the proportion of births not legally registered was of from 5.3 to 6.6% of the hospital births. Cost, negligence and legitimacy were the main reasons given for not registering births legally. The average time taken to make the registration was 26.5 days( standard deviation of 52 days) and 88.7% of the families did it by the 60th day from the date of the birth. A statistical association was detected between the act of registration and the period within which registration is required (within 60 days from birth) and type of delivery, maternal age and education. The official proportion of home deliveries was 0.5%;however, after the research the value was found to be somewere between 0.13 and 0.3% of all the registered births - only 36.8% were really born at home. Reasons for home deliveries were: option, "there wasn't a means of transport to take the pregnant woman to hospital" and "there wasn't enough time to get to a hospital"

Feature extraction for the analysis of colon status from the endoscopic images

BACKGROUND: Extracting features from the colonoscopic images is essential for getting the features, which characterizes the properties of the colon. The features are employed in the computer-assisted diagnosis of colonoscopic images to assist the physician in detecting the colon status. METHODS: Endoscopic images contain rich texture and color information. Novel schemes are developed to extract new texture features from the texture spectra in the chromatic and achromatic domains, and color features for a selected region of interest from each color component histogram of the colonoscopic images. These features are reduced in size using Principal Component Analysis (PCA) and are evaluated using Backpropagation Neural Network (BPNN). RESULTS: Features extracted from endoscopic images were tested to classify the colon status as either normal or abnormal. The classification results obtained show the features' capability for classifying the colon's status. The average classification accuracy, which is using hybrid of the texture and color features with PCA (τ = 1%), is 97.72%. It is higher than the average classification accuracy using only texture (96.96%, τ = 1%) or color (90.52%, τ = 1%) features. CONCLUSION: In conclusion, novel methods for extracting new texture- and color-based features from the colonoscopic images to classify the colon status have been proposed. A new approach using PCA in conjunction with BPNN for evaluating the features has also been proposed. The preliminary test results support the feasibility of the proposed method

The impact of insecticide treated curtains on dengue virus transmission: A cluster randomized trial in Iquitos, Peru

Dengue is one of the most important vector-borne diseases, resulting in an estimated hundreds of millions of infections annually throughout the tropics. Control of dengue is heavily dependent upon control of its primary mosquito vector, Aedes aegypti. Innovative interventions that are effective at targeting the adult stage of the mosquito are needed to increase the options for effective control. The use of insecticide-treated curtains (ITCs) has previously been shown to significantly reduce the abundance of Ae. aegypti in and around homes, but the impact of ITCs on dengue virus (DENV) transmission has not been rigorously quantified. A parallel arm cluster-randomized controlled trial was conducted in Iquitos, Peru to quantify the impact of ITCs on DENV seroconversion as measured through plaque-reduction neutralization tests. Seroconversion data showed that individuals living in the clusters that received ITCs were at greater risk to seroconverting to DENV, with an average seroconversion rate of 50.6 per 100 person-years (PY) (CI: 29.9–71.9), while those in the control arm had an average seroconversion rate of 37.4 per 100 PY (CI: 15.2–51.7). ITCs lost their insecticidal efficacy within 6 months of deployment, necessitating re-treatment with insecticide. Entomological indicators did not show statistically significant differences between ITC and non-ITC clusters. It’s unclear how the lack of protective efficacy reported here is attributable to simple failure of the intervention to protect against Ae. aegypti bites, or the presence of a faulty intervention during much of the follow-up period. The higher risk of dengue seroconversion that was detected in the ITC clusters may have arisen due to a false sense of security that inadvertently led to less routine protective behaviors on the part of households that received the ITCs. Our study provides important lessons learned for conducting Randomized Cluster Trials for vector control interventions against Aedes-transmitted virus infections