Novel multipath mitigation methods using a dual-polarization antenna

There are many methods for mitigating GNSS multipath errors. However, none of them completely eliminate the effects of multipath or suit all GNSS applications. A new class of multipath mitigation methods exploit new dual-polarization antenna technology. GNSS signals received direct from the satellites have right-handed circular polarization (RHCP), whereas (singly) reflected signals have left-handed circular polarization (LHCP) or an elliptical polarization that may be expressed as the sum of RHCP and LHCP components. Conventional GNSS user antennas are more sensitive to signals with RHCP, attenuating LHCP signals and reducing, but not eliminating, the multipath errors in the receiver. An antenna with the opposite polarization sensitivity will attenuate the direct signals more than the reflected signals. This can be used to characterizing the reflected signals and thus mitigate the effects of multipath interference.Experimental work using an Antcom dual-polarization antenna and dual geodetic receivers is presented. This verifies that carrier power to noise density, C/N-0, measurements obtained by separately correlating the RHCP and LHCP antenna outputs can be used to distinguish between a low-multipath and moderate-multipath environment. This may be used as the basis of a multipath detection technique.Three different multipath mitigation techniques that use a dual-polarization antenna are proposed. Measurement weighting estimates the code and carrier multipath error standard deviation from the RHCP-LHCP C/N-0 difference and elevation angle. This is used by the navigation processor to discard and reweight measurements. Range-domain multipath correction, uses the pseudo-range, carrier-phase and C/N-0 differences between the outputs of RHCP and LHCP receiver tracking channels, together with antenna calibration data, to estimate corrections to the code and carrier measurements. In tracking-domain multipath mitigation, the RHCP and LHCP correlator outputs are input to common acquisition and tracking algorithms which attempt to separate the direct line of sight and reflected signalsThe design of a novel dual-input GNSS front end, based on direct RF sampling, is presented This will be used, in conjunction with a software GNSS receiver, for future development and testing of multipath mitigation using a dual-polarization antenna

Optical characterisation of micro-fabricated Fresnel zone plates for atomic waveguides

We optically assess Fresnel zone plates (FZPs) that are designed to guide cold atoms. Imaging of various ring patterns produced by the FZPs gives an average RMS error in the brightest part of the ring of 3% with respect to trap depth. This residue is attributed to the imaging system, incident beam shape and FZP manufacturing tolerances. Axial propagation of the potentials is presented experimentally and through numerical simulations, illustrating prospects for atom guiding without requiring light sheets

A prospective study of arthroscopic evaluation of patients with chronic shoulder pain

Background: Shoulder pain is a common musculoskeletal complaint that may be due either to intrinsic disorders of the shoulder or referred pain. In this study, we aimed to find out the sensitivity and specificity of the clinical and radiological methods in diagnosing the chronic shoulder problems and to compare clinical and radiological diagnosis with arthroscopic diagnosis.Methods: After obtaining approval of the institutional ethics committee, we enrolled patients who presented with chronic shoulder pain in the outpatient clinic of Department of Orthopedics, DY Patil Medical College and Hospital, Navi Mumbai from August 2003 till August 2005. We obtained historical data of each patient in detail and made clinical, radiological and arthroscopic diagnosis. The findings from each diagnostic modality were compared and analysed.Results: During the study period, 34 patients were enrolled in the study. Injury was traumatic in 32% of the patients and 50% of all patients were heavy workers by occupation. Half of all the patients had pain in shoulder for more than 6 months. Clinical diagnosis of biceps tendinitis was made in 44% of patients, but radiological and arthroscopic diagnosis of biceps tendinitis was made in 18% and 12% respectively. Impingement was diagnosed in 29% patients clinically, in 15% patients radiologically and in 21% patients arthroscopically. Rotator cuff injury was diagnosed in 26% patients clinically, in 41% patients radiologically and in 67% patients arthroscopically. Conclusions: Findings from this single centre study suggest that arthroscopy can diagnose and treat conditions causing chronic shoulder pain, which is cost effective as well

A study of disability in patients with chronic musculoskeletal pain

Background: Musculoskeletal impairment is the most common cause of chronic pain and subsequent disability world over. Yet their very few Indian studies on this subject. The aim of study was to assess the extent of disability in out-patients suffering from chronic musculoskeletal pain, to determine whether the disability varied with the age and sex of the patient, to assess any correlation between the intensity of pain and the extent of disability, and to evaluate whether the extent of disability depended upon the site, periodicity and duration of pain.Methods: The 200 patients of chronic musculoskeletal pain were assessed for disability using the pain disability questionnaire (PDQ) and pain intensity using the numeric pain rating scale. The patients with mild, moderate and severe disability were compared using non parametric tests to assess the differences related to age, sex, pain intensity, site, duration and periodicity of pain.Results: The 56% patients had mild, 41% had moderate while 3% patients reported severe disability. Disability was higher in patients in the younger age group, higher intensity of pain, heel pain and variable pain. In the regression analysis, pain intensity emerged as the sole predictor of disability.Conclusions: We conclude that 56% patients had mild, 41% had moderate while 3% patients reported severe disability. Disability was higher in patients at the extremes of age, higher intensity of pain, and variable pain. Gender and pain duration did not have any significant association with disability

Comparing functional outcome in lateral end clavicle fracture after conservative and plating

Background: Fractures of the clavicle have been traditionally treated non- operatively but has been associated with various postoperative complications. In this study, we analyzed the outcomes of the operative management and compare its results with conservative treatment considering it as standard treatment option.Methods: The present study was carried out at the Department of Orthopedics, DY Patil Medical College and Hospital, Navi Mumbai. Open fractures, fractures associated with complication like head injury with associated other bone injuries were included in this study. We excluded patients less than 18 years of age, patients with middle third fracture of clavicle and patients with medial end clavicle fracture. The fractures were classified according to Robinson’s classification. Patients were followed up every week for 4 weeks then at 8 weeks, 12 weeks, 6 months and 1 year. The functional outcomes were assessed by Constant and Murley score.Results: We included 48 patients in the study, 34 of which were males, average age of the patients was 37.53±7.64 years. 23 injuries were on the left. There was statistically significant better union times with operative management (p=0.034). Various complications were observed like infection, implant failure, man union, non-union, deformity and skin infections, statistically seen more in patients who underwent conservative management. Overall, patients experienced excellent and good results with operative management in 6 and 12 patients respectively.Conclusions:Operative treatment gave statistically significant functional outcome and early healing compared to conservatively treated in displaced, communited lateral end clavicle fractures. 

UJI TOKSISITAS EKSTRAK AIR DAUN KELOR (Moringan oleifera, L) ASAL LAHAN KERING NUSA TENGGARA TIMUR

Moringa Oleifera (Moringa oleifera Lamk) found excessive growth in dry East Nusa Tenggara (NTT) province. The plant has not only been primarily consumed as food especially for its leaves but also is rich in nutrients in its fruits to roots, benefits as coagulants, vitamins, and medicines.  This research studied the toxic effect of the water extract of Moringa leaves to Artemia Salina Leach shrimp larvae according to BST method using water (room temperature) as a solvent, a preliminary study of the antibacterial and the anticancer target of study of the Morinaga. Moringa leaves were macerated for 3 x 24 hours using water, the results of phytochemical tests identified secondary metabolic content, among others, alkaloids, flavonoids, triterpenes, and tannins. The results of the BSLT test showed that the water extract (room temperature) of Moringa leaves had a toxicity level against Artemia Salina Leach as indicated by an LC50 value of 888, 34 less than 1000 ppm. It can be concluded that Moringa leaves have potential as a plant which can later be used as anti-bacterial and anti-cancer

Discovering Valuable Items from Massive Data

Suppose there is a large collection of items, each with an associated cost and an inherent utility that is revealed only once we commit to selecting it. Given a budget on the cumulative cost of the selected items, how can we pick a subset of maximal value? This task generalizes several important problems such as multi-arm bandits, active search and the knapsack problem. We present an algorithm, GP-Select, which utilizes prior knowledge about similarity be- tween items, expressed as a kernel function. GP-Select uses Gaussian process prediction to balance exploration (estimating the unknown value of items) and exploitation (selecting items of high value). We extend GP-Select to be able to discover sets that simultaneously have high utility and are diverse. Our preference for diversity can be specified as an arbitrary monotone submodular function that quantifies the diminishing returns obtained when selecting similar items. Furthermore, we exploit the structure of the model updates to achieve an order of magnitude (up to 40X) speedup in our experiments without resorting to approximations. We provide strong guarantees on the performance of GP-Select and apply it to three real-world case studies of industrial relevance: (1) Refreshing a repository of prices in a Global Distribution System for the travel industry, (2) Identifying diverse, binding-affine peptides in a vaccine de- sign task and (3) Maximizing clicks in a web-scale recommender system by recommending items to users