Investigation of image enhancement techniques for the development of a self-contained airborne radar navigation system

This study was devoted to an investigation of the feasibility of applying advanced image processing techniques to enhance radar image characteristics that are pertinent to the pilot's navigation and guidance task. Millimeter (95 GHz) wave radar images for the overwater (i.e., offshore oil rigs) and overland (Heliport) scenario were used as a data base. The purpose of the study was to determine the applicability of image enhancement and scene analysis algorithms to detect and improve target characteristics (i.e., manmade objects such as buildings, parking lots, cars, roads, helicopters, towers, landing pads, etc.) that would be helpful to the pilot in determining his own position/orientation with respect to the outside world and assist him in the navigation task. Results of this study show that significant improvements in the raw radar image may be obtained using two dimensional image processing algorithms. In the overwater case, it is possible to remove the ocean clutter by thresholding the image data, and furthermore to extract the target boundary as well as the tower and catwalk locations using noise cleaning (e.g., median filter) and edge detection (e.g., Sobel operator) algorithms

VTOL shipboard letdown guidance system analysis

Alternative letdown guidance strategies are examined for landing of a VTOL aircraft onboard a small aviation ship under adverse environmental conditions. Off line computer simulation of shipboard landing task is utilized for assessing the relative merits of the proposed guidance schemes. The touchdown performance of a nominal constant rate of descent (CROD) letdown strategy serves as a benchmark for ranking the performance of the alternative letdown schemes. Analysis of ship motion time histories indicates the existence of an alternating sequence of quiescent and rough motions called lulls and swells. A real time algorithms lull/swell classification based upon ship motion pattern features is developed. The classification algorithm is used to command a go/no go signal to indicate the initiation and termination of an acceptable landing window. Simulation results show that such a go/no go pattern based letdown guidance strategy improves touchdown performance

Sensitivity analysis of helicopter IMC decelerating steep approach and landing performance to navigation system parameters

Results of a study to investigate, by means of a computer simulation, the performance sensitivity of helicopter IMC DSAL operations as a function of navigation system parameters are presented. A mathematical model representing generically a navigation system is formulated. The scenario simulated consists of a straight in helicopter approach to landing along a 6 deg glideslope. The deceleration magnitude chosen is 03g. The navigation model parameters are varied and the statistics of the total system errors (TSE) computed. These statistics are used to determine the critical navigation system parameters that affect the performance of the closed-loop navigation, guidance and control system of a UH-1H helicopter

The Anatomy of a Weight Recidivism and Revision Bariatric Surgical Clinic

Abstract. Weight recidivism in bariatric surgery failure is multifactorial. It ranges from inappropriate patient selection for primary surgery to technical/anatomic issues related to the original surgery. Most bariatric surgeons and centers focus on primary bariatric surgery while weight recidivism and its complications are very much secondary concerns. Methods. We report on our initial experience having established a dedicated weight recidivism and revisional bariatric surgery clinic. A single surgeon, dedicated nursing, dieticians, and psychologist developed care maps, goals of care, nonsurgical candidate rules, and discharge planning strategies. Results. A single year audit (2012) of clinical activity revealed 137 patients, with a mean age 49 ± 10.1 years (6 years older on average than in our primary clinic), 75% of whom were women with BMI 47 ± 11.5. Over three quarters had undergone a vertical band gastroplasty while 15% had had a laparoscopic adjustable gastric band. Only 27% of those attending clinic required further surgery. As for primary surgery, the role of the obesity expert clinical psychologist was a key component to achieving successful revision outcomes. Conclusion. With an exponential rise in obesity and a concomitant major increase in bariatric surgery, an inevitable increase in revisional surgery is becoming a reality. Anticipating this increase in activity, Alberta Health Services, Alberta, Canada, has established a unique and dedicated clinic whose early results are promising

Modeling methodology for MLS range navigation system errors using flight test data

Flight test data was used to develop a methodology for modeling MLS range navigation system errors. The data used corresponded to the constant velocity and glideslope approach segment of a helicopter landing trajectory. The MLS range measurement was assumed to consist of low frequency and random high frequency components. The random high frequency component was extracted from the MLS range measurements. This was done by appropriate filtering of the range residual generated from a linearization of the range profile for the final approach segment. This range navigation system error was then modeled as an autoregressive moving average (ARMA) process. Maximum likelihood techniques were used to identify the parameters of the ARMA process

A descriptive study of gender preference and its relation to willingness for sterilization in pregnant women in a tertiary hospital in Goa

Background: There is an association between male gender preference and avoidance of ligation if preferred sex is not born. We therefore undertook this study to systematically analyze this association between the gender preference and willingness for sterilization in Goan women.Methods: A hospital based cross sectional descriptive study was undertaken among 216 women attending antenatal clinic at a tertiary hospital in Goa between August to December 2015. The data was analyzed in SPSS for Windows, version 14.0. The results are described as percentages and assessment of statistically significant difference was done using the Chi-Square test at 95% level of significance (p<0.05).Results: Of the 216 women who participated in the study, 50 (23.1%) had a male preference. Age, education of the women and religion were not found to be having a statistically significant association with the male preference. Occupation, socio-economic status of the women and parity were found to be having a statistically significant association with the male preference. The women with one surviving male child did not mind if the second child was female but those with previous female child desired for male child in most instances. Eighty three percent of women with preference for female child were willing for ligation even if their preference was not met compared to only 50% of those with male preference.Conclusions: The decision on completion of family as evident from willingness for sterilization is influenced by the sex preference and the outcome of pregnancy in terms of the sex of the child

Prostaglandins in breast cancer: relationship to disease stage and hormone status.

Tissue prostaglandin (PG) content and production by human breast cancers were measured in 24 human mammary carcinoma specimens. The 5 compounds studied were PGE1, PGE2, PGF2 alpha, 6-keto-PGF1 alpha, and TXB2. The tissue content of all 5 compounds was higher in neoplastic tissue in comparison with the paired noncancerous breast tissue. However, microsomal PG synthetase activity in vitro in noncancerous and neoplastic breast tissue was comparable. Increased thromboxane formation was associated with three clinical variables--tumour size, axillary lymph node metastases and distant metastasis. A lesion negative for either oestrogen or progesterone receptor content tended to produce more TXB2 but lower PGE2 and 6-keto-PGF1 alpha. Results obtained in this pilot study may provide clues as to what direction future larger studies could take in the search for reliable prognostic indicators for breast cancer

SYNTHESIS, CHARACTERIZATION AND EVALUATION OF 4-HYDROXY-1-PHENYL/METHYL-3-(3-SUBSTITUTED-1-(SUBSTITUTEDIMINO) PROPYL) QUINOLINE-2(1H)-ONE DERIVATIVES AND 4-HYDROXY-1-PHENYL/METHYL-3-(1-(SUBSTITUEDIMINO) ETHYL) QUINOLINE-2(1H)-ONE DERIVATIVES AS POSSIBLE ANTICANCER AGENTS

Objective: Synthesis, characterization and evaluation of quinolin-2-one derivatives as possible anticancer agents.Methods: A series of novel 4-hydroxy-1-phenyl/methyl-3-(3-substituted-1-(substitutedimino)propyl)quinolin-2(1H)-one derivatives IIa(1-5)/IIb(1-5) and 4-hydroxy-1-phenyl/methyl-3-(1-(substituedimino)ethyl)quinolin-2(1H)-one derivatives IIIa(1-3)/IIIb(1-3) were synthesised by nucleophilic addition of substituted anilines on 3-acetyl-4-hydroxy-1-phenyl/methylquinolin-2(1H)-one (a/b) and 4-hydroxy-3-(3-substitutedpropanoyl)-1-phenyl/methyl quinolin-2(1H)-one (Ia/Ib); respectively. The synthesised derivatives were characterised by spectral analysis and were tested for their in vitro anticancer activity against K562 and Hep 3b cell lines by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay method.Results: The compounds were tested for their in vitro anticancer activity against K562 and Hep 3b cell lines at 10, 20, 25, 30 and 50 µg/ml concentration using MTT assay method. The compound 4-hydroxy-3-(3-morpholino-1-(phenylimino)propyl)-1-phenylquinolin-2(1H)-one (IIa-1) showed anticancer activity with IC50 value 20 µg as compared to the control against K562 cell lines. The compound 4-hydroxy-1-phenyl-3-(1-(phenylimino) ethyl) quinolin-2(1H)-one (IIIa-1) showed anticancer activity with IC50 value less than 10 µg.Conclusion: The proposed method for the synthesis of novel derivatives is convenient and gives a good yield. Some of the synthesised compounds showed promising anticancer activity against K562 and Hep 3b cell lines. Compound IIa-1 (R=-C6H5; R1= morpholine; R2= C6H5-NH-) exhibited most potent activity against K562 cell lines. Compound IIIa-1 (R=-C6H5; R3= C6H5-NH-) has been proved to be the most cytotoxic compound among the other derivatives against Hep 3b cell lines