New CFAR algorithm and circuit development for radar receiver

Automatic target detection radar requires adaptive thresholding achieved by the Constant False Alarm Rate (CFAR) circuit to control the false alarm caused by variations in the background clutter. This thesis deal with the problem that happened when an abrupt variation in background clutter merged with a multi-interfering target, and when the clutter cloud itself centered with multi-interfering targets. To detect targets in such environments, it needs a robust CFAR algorithm that excises the target spikes and clutter edges from the CFAR window to give the best possible estimation of the noise background. The Maximum Spike Subtraction MSS-CFAR family that uses two lock circuits to find two maximum spikes in the CFAR window that subtracted from sample summing to make better background noise estimation that used to construct an adaptive threshold. The MSS-CFAR family is MSS-CA�CFAR, MSS-GO-CFAR, and MSS-SO-CFAR, MSS-CFAR family in addition to two core algorithms were studied which are cell averaged CA-CFAR family that includes the greatest of GO-CFAR and smallest of SO-CFAR and ordered statistics OS-CFAR family that include greatest of ordered statistics OSGO-CFAR and the smallest of ordered statistics OSSO-CFAR. All these algorithms are simulated using MATLAB and applied them to three different clutter models that represent different environment cases. The CA-CFAR family failed to handle models two and three also OS-CFAR family except for OS-CFAR that handle all models successfully. For the MSS-CFAR family, MSS-CA-CFAR could handle all models successfully, and comparing with OS-CFAR, the MSS-CA-CFAR need less hardware and processing time because it did not need a sorting process that is essential for OS-CFAR. Therefore, the MSS-CA-CFAR is chosen to implement by practical digital circuit and there is another important feature in the MSS-CFAR algorithm that is parallel processing since the spike selection process is done at the same time with summing of samples process that makes this algorithm much less in processing time from any other algorithm using the same environment. The last MATLAB test for MSS-CA- vi CFAR with a spiky exponential model shown in Table 4.3 in chapter four shows clearly that MSS-CA-CFAR detects nine targets from ten that means the efficiency of detection of the proposed method is 90%. The field-programmable gate array FPGA chip that is used to implement the MSS-CA-CFAR algorithm needs only three signals from the radar receiver to match with the receiver circuit correctly which are time base clock signal period reset trigger signal and the pulse duration time

Performance Evaluation and Optimization of Math-Similarity Search

Similarity search in math is to find mathematical expressions that are similar to a user's query. We conceptualized the similarity factors between mathematical expressions, and proposed an approach to math similarity search (MSS) by defining metrics based on those similarity factors [11]. Our preliminary implementation indicated the advantage of MSS compared to non-similarity based search. In order to more effectively and efficiently search similar math expressions, MSS is further optimized. This paper focuses on performance evaluation and optimization of MSS. Our results show that the proposed optimization process significantly improved the performance of MSS with respect to both relevance ranking and recall.Comment: 15 pages, 8 figure

Regional mean sea surface and mean dynamic topography models around Malaysian seas developed from 27 years of along-track multi-mission satellite altimetry data

Contemporary Universiti Teknologi Malaysia 2020 Mean Sea Surface (UTM20 MSS) and Mean Dynamic Topography (UTM20 MDT) models around Malaysian seas are introduced in this study. These regional models are computed via scrutinizing along-track sea surface height (SSH) points and specific interpolation methods. A 1.5-min resolution of UTM20 MSS is established by integrating 27 years of along-track multi-mission satellite altimetry covering 1993–2019 and considering the 19-year moving average technique. The Exact Repeat Mission (ERM) collinear analysis, reduction of sea level variability of geodetic mission (GM) data, crossover adjustment, and data gridding are presented as part of the MSS computation. The UTM20 MDT is derived using a pointwise approach from the differences between UTM20 MSS and the local gravimetric geoid. UTM20 MSS and MDT reliability are validated with the latest Technical University of Denmark (DTU) and Collecte Localisation Services (CLS) models along with coastal tide gauges. The findings presented that the UTM20, CLS15, and DTU18 MSS models exhibit good agreement. Besides, UTM20 MDT is also in good agreement with CLS18 and DTU15 MDT models with an accuracy of 5.1 and 5.5 cm, respectively. The results also indicate that UTM20 MDT statistically achieves better accuracy than global models compared to tide gauges. Meanwhile, the UTM20 MSS accuracy is within 7.5 cm. These outcomes prove that UTM20 MSS and MDT models yield significant improvement compared to the previous regional models developed by UTM, denoted as MSS1 and MSS2 in this study

Comparison of the Knowledge in Core Policies of Essential Drug List Among Medical Practitioners and Medical Students in Galle, Sri Lanka

Selection of the best and safest medicine should be one of the national economic policies in a country for good health care services. Introduction of detailed module in rational use of medicine (RUM) to pharmacology syllabus needed prior analysis of the existing knowledge among health care workers. Therefore we assessed the knowledge and attitudes of essential drug list (EDL) on medical practitioners (MPs) and medical students (MSs). Forty two MPs and 120 MSs from hospital and Faculty of Medicine were given a pretested structured questionnaire related to core policies of EDL, contents, criteria for selection and time frame for revision in RUM. Our study showed that only 29% of MPs were confident about their knowledge in EDL and 17% of them had marked it as don’t know. Study was expanded for quantitative analysis of the knowledge on the core policies of EDL on them. Knowledge on contents, criteria for selection and the time frame for revision of EDL were 63%, 83% and 17% in MPs. Of MSs, 87% had sound knowledge in core contents, 32% in criteria for selection and only 50% of MSs were aware about the correct time frame of revision of EDL. Knowledge in contents of EDL was higher in MSs (87%) than MPs(63&). MPs were not aware about EDL preparing criteria such as inclusion of generic names, common ailment, majority ailments of the people (59%, 56% and 56% respectively). In contrast, MSs had > 93% of the knowledge in all three areas. However MSs had poorer knowledge (32%) in criteria for selection of EDL than MPs (83%). Knowledge in time frame for revision of EDL was 17% in MPs and 50% in MSs. We found that MPs in the service were not convinced about their knowledge in EDL. Deficiency was significant in the core contents of the EDL preparation. Therefore we suggest that MPs need repetitive in-service training programme for practicing of RUM in the national health facilities. We need to reiterative programme in the core curriculum regarding the criteria for EDL selection. Though MSs had good knowledge in content of EDL, they are poor in criteria for selection and time frame for revision

Individualisation of time-motion analysis : a method comparison and case report series

© Georg Thieme Verlag KG. This study compared the intensity distribution of time-motion analysis data, when speed zones were categorized by different methods. 12 U18 players undertook a routine battery of laboratory- and field-based assessments to determine their running speed corresponding to the respiratory compensation threshold (RCT), maximal aerobic speed (MAS), maximal oxygen consumption (vVO 2max ) and maximal sprint speed (MSS). Players match-demands were tracked using 5 Hz GPS units in 22 fixtures (50 eligible match observations). The percentage of total distance covered running at high-speed (%HSR), very-high speed (%VHSR) and sprinting were determined using the following speed thresholds: 1) arbitrary; 2) individualised (IND) using RCT, vVO 2max and MSS; 3) individualised via MAS per se; 4) individualised via MSS per se; and 5) individualised using MAS and MSS as measures of locomotor capacities (LOCO). Using MSS in isolation resulted in 61 % and 39 % of player's % HSR and % VHSR, respectively, being incorrectly interpreted, when compared to the IND technique. Estimating the RCT from fractional values of MAS resulted in erroneous interpretations of % HSR in 50 % of cases. The present results suggest that practitioners and researchers should avoid using singular fitness characteristics to individualise the intensity distribution of time-motion analysis data. A combination of players' anaerobic threshold, MAS, and MSS characteristics are recommended to individualise player-tracking data

Extended microsatellite analysis in microsatellite stable, MSH2 and MLH1 mutation-negative HNPCC patients: Genetic reclassification and correlation with clinical features

Background: Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominant disorder predisposing to predominantly colorectal cancer (CRC) and endometrial cancer frequently due to germline mutations in DNA mismatch repair (MMR) genes, mainly MLH1, MSH2 and also MSH6 in families seen to demonstrate an excess of endometrial cancer. As a consequence, tumors in HNPCC reveal alterations in the length of simple repetitive genomic sequences like poly-A, poly-T, CA or GT repeats (microsatellites) in at least 90% of the cases. Aim of the Study: The study cohort consisted of 25 HNPCC index patients ( 19 Amsterdam positive, 6 Bethesda positive) who revealed a microsatellite stable (MSS) - or low instable (MSI-L) - tumor phenotype with negative mutation analysis for the MMR genes MLH1 and MSH2. An extended marker panel (BAT40, D10S197, D13S153, D18S58, MYCL1) was analyzed for the tumors of these patients with regard to three aspects. First, to reconfirm the MSI-L phenotype found by the standard panel; second, to find minor MSIs which might point towards an MSH6 mutation, and third, to reconfirm the MSS status of hereditary tumors. The reconfirmation of the MSS status of tumors not caused by mutations in the MMR genes should allow one to define another entity of hereditary CRC. Their clinical features were compared with those of 150 patients with sporadic CRCs. Results: In this way, 17 MSS and 8 MSI-L tumors were reclassified as 5 MSS, 18 MSI-L and even 2 MSI-H ( high instability) tumors, the last being seen to demonstrate at least 4 instable markers out of 10. Among all family members, 87 malignancies were documented. The mean age of onset for CRCs was the lowest in the MSI-H-phenotyped patients with 40.5 +/- 4.9 years (vs. 47.0 +/- 14.6 and 49.8 +/- 11.9 years in MSI-L- and MSS-phenotyped patients, respectively). The percentage of CRC was the highest in families with MSS-phenotyped tumors (88%), followed by MSI-L-phenotyped ( 78%) and then by MSI-H-phenotyped (67%) tumors. MSS tumors were preferentially localized in the distal colon supposing a similar biologic behavior like sporadic CRC. MSH6 mutation analysis for the MSI-L and MSI-H patients revealed one truncating mutation for a patient initially with an MSS tumor, which was reclassified as MSI-L by analyzing the extended marker panel. Conclusion: Extended microsatellite analysis serves to evaluate the sensitivity of the reference panel for HNPCC detection and permits phenotype confirmation or upgrading. Additionally, it confirms the MSS status of hereditary CRCs not caused by the common mutations in the MMR genes and provides hints to another entity of hereditary CRC. Copyright (C) 2004 S. Karger AG, Basel

Traffic agents for improving QoS in mixed infrastructure and ad hoc modes wireless LAN

As an important complement to infrastructured wireless networks, mobile ad hoc networks (MANET) are more flexible in providing wireless access services, but more difficult in meeting different quality of service (QoS) requirements for mobile customers. Both infrastructure and ad hoc network structures are supported in wireless local area networks (WLAN), which can offer high data-rate wireless multimedia services to the mobile stations (MSs) in a limited geographical area. For those out-of-coverage MSs, how to effectively connect them to the access point (AP) and provide QoS support is a challenging issue. By mixing the infrastructure and the ad hoc modes in WLAN, we propose in this paper a new coverage improvement scheme that can identify suitable idle MSs in good service zones as traffic agents (TAs) to relay traffic from those out-of-coverage MSs to the AP. The service coverage area of WLAN is then expanded. The QoS requirements (e.g., bandwidth) of those MSs are considered in the selection process of corresponding TAs. Mathematical analysis, verified by computer simulations, shows that the proposed TA scheme can effectively reduce blocking probability when traffic load is light