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111.
Mohamed B. El Mashade 《Journal of The Franklin Institute》2011,348(6):941-972
In this article, we provide a complete detection analysis, in its exact form, of what is known as moderately fluctuating radar targets when the background environment contains a number of interfering targets along with the target under test. The illumination of this class of radar targets by a coherent pulse train, return a train of correlated pulses with a correlation coefficient in the range 0<ρ<1 (intermediate between SWII and SWI models). Since the adaptive detection is one of the desirable features for modern radar receivers, it becomes of importance to adaptively detect this class of targets. The attractive class of adaptive detectors is that based on order-statistics (OS) technique. The more advanced version of the OS algorithm, known as the generalized trimmed-mean (GTM) scheme, is chosen here to carry out this task. It implements trimmed averaging of a weighted ordered range samples. This processor is analyzed for the case where the radar receiver incorporates a postdetection integrator amongst its contents and where the operating environment is multitarget. The primary and the secondary interfering targets are assumed to be fluctuating in accordance with partially correlated χ2 fluctuation model. SWI and SWII well-known models represent the cases where the signal is completely correlated and completely decorrelated, respectively, from pulse to pulse. It is shown that the processor performance improves, for weak SNR of the primary target, as the correlation coefficient ρs increases and this occurs either in the absence or in the presence of spurious targets. For strong SNR, on the other hand, the processor performance degrades as ρs increases and the SWI and SWII models enclose the correlated target case and this behavior is common for all GTM based schemes. 相似文献
112.
Xu G Lee DY Xie H Chiew D Hsieh TM Ali EM Lun Looi X Li MH Ying JY 《Biomicrofluidics》2011,5(3):34107-341079
Sample preparation is one of the most crucial processes for nucleic acids based disease diagnosis. Several steps are required for nucleic acids extraction, impurity washes, and DNA/RNA elution. Careful sample preparation is vital to the obtaining of reliable diagnosis, especially with low copies of pathogens and cells. This paper describes a low-cost, disposable lab cartridge for automatic sample preparation, which is capable of handling flexible sample volumes of 10 μl to 1 ml. This plastic cartridge contains all the necessary reagents for pathogen and cell lysis, DNA/RNA extraction, impurity washes, DNA/RNA elution and waste processing in a completely sealed cartridge. The entire sample preparation processes are automatically conducted within the cartridge on a desktop unit using a pneumatic fluid manipulation approach. Reagents transportation is achieved with a combination of push and pull forces (with compressed air and vacuum, respectively), which are connected to the pneumatic inlets at the bottom of the cartridge. These pneumatic forces are regulated by pinch valve manifold and two pneumatic syringe pumps within the desktop unit. The performance of this pneumatic reagent delivery method was examined. We have demonstrated the capability of the on-cartridge RNA extraction and cancer-specific gene amplification from 10 copies of MCF-7 breast cancer cells. The on-cartridge DNA recovery efficiency was 54-63%, which was comparable to or better than the conventional manual approach using silica spin column. The lab cartridge would be suitable for integration with lab-chip real-time polymerase chain reaction devices in providing a portable system for decentralized disease diagnosis. 相似文献
113.
The case control study was conducted to quantify the amount of the carcinogenic tobacco specific nitrosamine in smokeless tobacco users and smokers in patients with oral leukoplakia and also to emphasize the role of tobacco-specific nitrosamine in the incidence of oral leukoplakia. The study was conducted on 30 patients. The urine samples were obtained from smokeless tobacco users with oral leukoplakia, smokers with oral leukoplakia and non-tobacco users (i.e. people who do not use tobacco in any form). The collected samples were processed by gas chromatography-mass spectrometry. A highly significant difference of NNAL[4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol] in smokeless tobacco users than tobacco smokers P = 0.0002 (Table 1) was obtained. This significant difference shows smokeless tobacco is more carcinogenic than smoked tobacco. This study confirmed that NNAL is a potent biomarker for calculating the risk of occurrence of carcinoma in smokeless tobacco users and smokers, and that smokeless tobacco is more harmful than smoked tobacco. 相似文献
114.
Research has documented overlapping and coexisting characteristics of learning disabilities (LD) and emotional and behavioural difficulties (EBD). Such concomitance may impact teacher referrals of children at risk for LD which in turn may influence service delivery. Using the Learning Disabilities Diagnostic Inventory (LDDI) and the Strengths and Difficulties Questionnaire (SDQ), we examined teachers’ ratings of EBD and LD symptoms in 439 students referred for LD in elementary schools in Oman. A multivariate analysis of variance (MANOVA) showed that there were no gender differences in LD symptoms, whereas there were significant gender differences in teachers’ ratings of hyperactivity and conduct problems in referred children. There was an association between teachers’ ratings on the LDDI and SDQ dimensions, reflecting children’s concurrent display of LD and EBD symptoms. Implications are discussed within an Omani context in which there is a need to increase teachers’ awareness of the behavioural and emotional profile of children at risk for LD. 相似文献
115.
Carmen Mohamed 《Education 3-13》2013,41(2):143-151
This article addresses the question as to whether training pre-school practitioners in an approach to anti-discriminatory education can impact on the developing attitudes of young children. This article attempts to analyse the effect of training practitioners in the delivery of an anti-discriminatory curriculum on the developing attitudes of the children they are teaching. This training was carried out with Leicestershire Foundation Stage settings. 相似文献
116.
Walaa Sayed Mohammad Osama Ragaa Abdelraouf Salam Mohamed Elhafez Nagui Sobhi Nassif 《Journal of sports sciences》2013,31(10):934-939
AbstractIn this study, we compared the isokinetic torques of hip flexors/extensors and abductors/adductors in soccer players suffering from osteitis pubis (OP), with normal soccer players. Twenty soccer male athletes with OP and 20 normal soccer athletes were included in this study. Peak torque/body weight (PT/BW) was recorded from hip flexor/extensor and abductor/adductor muscles during isokinetic concentric contraction modes at angular velocity of 2.1 rad · s?1, for both groups. The results showed a significant difference between the normal and OP groups for hip flexors (P < 0.05). The normal group had significant, lower PT/BW value than the OP group for their hip flexors (P < 0.05). The hip flexor/extensor PT ratio of OP affected and non-affected limbs was significantly different from that of normal dominant and non-dominant limbs. There were no significant differences between the normal and OP groups for hip extensor, adductor and abductor muscles (P > 0.05). Regarding the hip adductor/abductor PT ratio, there was no significant difference between the normal and OP groups of athletes (P > 0.05). The OP group displayed increase in hip flexor strength that disturbed the hip flexor/extensor torque ratio of OP. Therefore, increasing the hip extensor strength should be part of rehabilitation programmes of patients with OP. 相似文献
117.
Mohamed A. Nour AbdelRahman A. AbdelRahman Adam Fadlalla 《Government Information Quarterly》2008,25(3):448-461
The recent advances in the Internet technology have propelled the development of related applications in electronic communications and transactions, including electronic commerce and electronic government (e-government). There has been a proliferation of e-government initiatives worldwide undertaken under different forms of government, socioeconomic settings, and technological conditions. Nonetheless, the relationship between an e-government initiative and its context has not received adequate attention in the e-government literature. This paper provides an organizing framework that maps the core values (goals) of e-government to two fundamental factors; namely, the degree of e-government readiness and the level of democratization. The framework addresses the importance of the relationship between the context within which e-government initiatives are undertaken and the goals of those initiatives. From a conceptual perspective, this framework underscores the pivotal importance of the context of an e-government initiative in influencing the goals of this initiative. From a practical viewpoint, the framework provides a roadmap for policy makers to formulate policy goals of e-government initiatives commensurate with their respective environments. 相似文献
118.
119.
O’Brien Beth A. Mohamed Malikka Begum Habib Yussof Nurul Taqiah Ng Siew Chin 《Reading and writing》2019,32(4):909-937
Reading and Writing - Phonological awareness is critical for early reading acquisition across alphabetic as well as non-alphabetic languages. The grain size of phonological awareness varies with... 相似文献
120.
Educational institutions in the Arab Gulf are requiring rapid changes to enhance English language learning to keep up with globalization and economic growth. This urges the need for investigating policy changes such as effectiveness in curriculum orientations and their impact on the actual process of teaching in order to gauge how educational institutions are performing. This paper reports the findings of a survey study on curriculum enactment in the English Language Foundation Program of a higher education institution in the Arab Gulf region. Data collection methods included a survey and interview with teachers investigating their opinions about the curriculum, how much support it offers teachers to reach the objectives of the course, and whether/to what extent as well as the reasons why they feel they need to modify the curriculum at the implementation level. Results showed that most teachers exercised discretion in using the prescribed curriculum materials due to individual contextual factors. Results also indicated that either when implementing the prescribed or modified materials, most participants highlighted the importance of using reliable quality resource materials that can help teachers as well as students to enhance the learning process. Findings have implications for English as a second language curriculum design in Arab higher educational contexts. 相似文献