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Pejhman Ghassemi Mohammad Hossein Miranbaygi 《Journal of Zhejiang University. Science. B》2009,10(8):602-608
Measurement of optical properties of skin is an expanding and growing field of research. Recent studies have shown that the
biological tissue, especially skin, changes the polarization state of the incident light. Using this property will enable
the study of abnormalities and diseases that alter not only the light intensity but also its polarization state. In this paper
we report an experimental study for measuring changes of polarization state of the light scattered from a phantom similar
to a sample model of scattering skin. Using the notation of Stokes vector for the polarized light and Mueller matrix for the
sample with its polarization properties, we have shown that some elements of the matrix were particularly sensitive to the
changes of the polarization-altering physical properties of the scatterers within the phantom.
相似文献
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Studies were initiated for two consecutive years to find out the effect of time of transplanting and seedlings hill^-l on the productivity of rice in Dera Ismail Khan district of North West Frontier Province (NWFP), Pakistan. The experiment was laid out in a randomized complete block design with split plot arrangements. Main plots consisted of four transplanting dates viz. 20th and 27th of June and 4th and 1 lth of July while sub-plots contained 1, 2, 3 or 4 seedlings hill^-1. Among transplanting dates, June 20th planted crop gave highest paddy yield and net return with I seedling hill^-1. It explains that the use of more seedlings hill^-1 not only adds to cost but is also a mere wastage of natural resources. Based on research findings, we conclude that the use of I seedling hill^-1 is most appropriate for timely sowing otherwise 4 seedlings hill^-1 should be used to compensate for the yield gap in late transplanted rice. 相似文献
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Mohammad Abdi Mohammad Said Hakhamaneshi Mohammad Reza Alaei Namam-Ali Azadi Rahim Vakili Daniel Zamanfar Mohammad Taghikhani Shohreh Khatami 《Indian journal of clinical biochemistry : IJCB》2015,30(3):318-322
Methods for assaying lysosomal diseases in dried blood samples are very useful today due to its several advantages related to the stability of samples, its transportation, handled and analysis, and its potential use for newborn screening compared to traditional methods in leucocytes samples. For this reason, it is important to validate these assays before being used in routine laboratory. Because of different in biological markers based on ethnicity, we aimed this study to validation a DBS-based fluorometric assay for measurement of α-l-Iduronidase activity for diagnosis of MPS I patients in Iran. DBS samples were collected from 15 MPS I patients and 60 healthy age matched subjects. Diagnostic value, biological variance and α-l-Iduronidase activity were determined. DBS α-l-Iduronidase activity was significantly higher in male subjects than in female group. Using a cut-off level of 1.08 µmol/spot 20 h, sensitivity and specificity were 100 and 98 %. The linearity of test was proved and we showed that within-run and between run precision were 5.6 and 14.66 %. Measurement of α-l-Iduronidase activity in DBS samples is an accurate test for diagnosis of MPS I and because of its rapid shipping and simplicity to keeping, DBS-based enzyme activity could be considered as a useful diagnostic tool in this disease. 相似文献
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Mohammad Akshir Ab Kadir 《Cambridge Journal of Education》2017,47(2):227-246
Among the major policies that have been implemented to ensure its continued success, Thinking Schools, Learning Nation (TSLN) has been described as the ‘big bang of educational reforms’ in Singapore. However, while the policy aims to develop critical thinkers in school leavers, the corporatisation of education in the shape of structures such as the school excellence model seems to be at odds with TSLN. This paper argues that these structures unwittingly engender a culture of performativity among schools, marginalising the central outcome of its initiative that entails developing a culture of thinking and thinkers. The tension is further exacerbated by the larger rationalities that have shaped Singapore and the pragmatic and instrumental philosophy which underpins its educational system. The tensions generated by the clash between intended (culture of thinking) and engendered culture (culture of performativity) present the challenge of mediation for the system on its path to realising TSLN. 相似文献
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Zeinab Echreshavi Mokhtar Shasadeghi Mohammad Hassan Asemani 《Journal of The Franklin Institute》2021,358(1):575-605
This paper focuses on a systematic constrained fuzzy integral sliding mode controller design for a class of uncertain discrete-time nonlinear systems which can be represented as Takagi-Sugeno (T-S) fuzzy models. The contributions are to consider constraints on the control input amplitude and control input amplitude rate and to extend the existing pole-placement design technique for designing gain matrices of the fuzzy sliding surface. Moreover, a dynamic-gain observer along with performance is proposed for attenuating disturbance, which generalizes the existing results on the Proportional Observer (PO), the Proportional Integral Observer (PIO) and the dynamic observer (DO). Finally, the dynamic-observer-based constrained fuzzy integral sliding mode controller is designed. All the proposed design conditions are represented in terms of LMIs-based ones. The methods are studied for not only single-input single-output (SISO) but also multi-input multi-output (MIMO) systems. In the end, the proposed approaches are evaluated on practical and numerical systems to illustrate the superiority of the proposed control scheme. 相似文献
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Faezeh Farivar Mahdi Aliyari Shoorehdeli Mohammad Teshnehlab 《Journal of The Franklin Institute》2012,349(7):2243-2267
Despite active research and significant progress in the last three decades on control of human eye movements, it remains challenging issue due to its applications in prosthetic eyes and robotics. Till now, no considerable investigation of this subject is presented in the interdisciplinary sciences. The goal of this paper is to present a distinguished survey of existing literature on the intelligent control of the human eye movements system applied in a huggable pet-type robot as a biomechatronic system.In this study, the basic knowledge of human eye movements control is explained to show how the neural networks in the brainstem control the human eye movements. The geometry and model of human eye movements system are investigated and this system is considered as a nonlinear control system. The specified model may only be an academic exercise. It can have scientific importance in understanding of the human movement system in general. Also, it can be useful for robotics.Intelligent methods such as artificial neural networks and fuzzy neural networks are proposed to control the human eye movements and numerical simulations are presented. It is discussed that the intelligent controls applied to control of human eye movements system are emulated from the neural controls in biological system. 相似文献