Towards skin polarization characterization using polarimetric technique     

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   

Characterization of a-Si:H/SiN multilayer waveguide polarization using an optical pumping application—LED   总被引：1，自引：1，他引：0  

Mohd Saiful Dzulkefly Zan  Isamu Kato  Mohammad Syuhaimi Ab-Rahman  Seri Mastura Mustaza 《浙江大学学报(A卷英文版)》2009,10(10):1421-1427

This paper describes the fabrication of a waveguide and the analysis of its polarization characteristics by applying light-emitting diode （LED） pumping lights to its surface. By using double tubed coaxial line （DTCL） microwave plasma chemical vapor deposition （MPCVD） equipment, an a-Si：H/SiN multilayer waveguide was fabricated whose thickness could be controlled at nanometer order. The main structural material of the waveguide sample consisted of a combination of layers of amorphous silicon hydrogen and silicon nitrate. Once the sample was ready, another major objective of the experiment was to analyze the polarization characteristics of the fabricated waveguide. The idea of the experiment was to analyze how the waveguide reacts when three types of LED （blue, yellow, and red） are radiated onto its surface. The results showed that the fabrication of the a-Si：H/SiN sample is successful. Most effective transmission results, which accord with the polarization characteristics analysis, were obtained.  相似文献   

Speaker adapted dynamic lexicons containing phonetic deviations of words     

Bahram Vazirnezhad  Farshad Almasganj  Seyed Mohammad Ahadi  Ari Chanen 《浙江大学学报(A卷英文版)》2009,10(10):1461-1475

Speaker variability is an important source of speech variations which makes continuous speech recognition a difficult task. Adapting automatic speech recognition （ASR） models to the speaker variations is a well-known strategy to cope with the challenge, Almost all such techniques focus on developing adaptation solutions within the acoustic models of the ASR systems. Although variations of the acoustic features constitute an important portion of the inter-speaker variations, they do not cover variations at the phonetic level. Phonetic variations are known to form an important part of variations which are influenced by both micro-segmental and suprasegmental factors. Inter-speaker phonetic variations are influenced by the structure and anatomy of a speaker＇s articulatory system and also his/her speaking style which is driven by many speaker background characteristics such as accent, gender, age, socioeconomic and educational class. The effect of inter-speaker variations in the feature space may cause explicit phone recognition errors. These errors can be compensated later by having appropriate pronunciation variants for the lexicon entries which consider likely phone misclassifications besides pronunciation. In this paper, we introduce speaker adaptive dynamic pronunciation models, which generate different lexicons for various speaker clusters and different ranges of speech rate. The models are hybrids of speaker adapted contextual rules and dynamic generalized decision trees, which take into account word phonological structures, rate of speech, unigram probabilities and stress to generate pronunciation variants of words. Employing the set of speaker adapted dynamic lexicons in a Farsi （Persian） continuous speech recognition task results in word error rate reductions of as much as 10.1% in a speaker-dependent scenario and 7.4% in a speaker-independent scenario.  相似文献   

To be or not to be in social media: How brand loyalty is affected by social media?     

Michel Laroche  Mohammad Reza Habibi  Marie-Odile Richard 《International Journal of Information Management》2013

There is an ongoing debate over the activities of brands and companies in social media. Some researchers believe social media provide a unique opportunity for brands to foster their relationships with customers, while others believe the contrary. Taking the perspective of the brand community building plus the brand trust and loyalty literatures, our goal is to show how brand communities based on social media influence elements of the customer centric model (i.e., the relationships among focal customer and brand, product, company, and other customers) and brand loyalty. A survey-based empirical study with 441 respondents was conducted. The results of structural equation modeling show that brand communities established on social media have positive effects on customer/product, customer/brand, customer/company and customer/other customers relationships, which in turn have positive effects on brand trust, and trust has positive effects on brand loyalty. We find that brand trust has a fully mediating role in converting the effects of enhanced relationships in brand community to brand loyalty. The implications for marketing practice and future research are discussed.  相似文献   

Reference Ranges for Serum Total Cholesterol, HDL-Cholesterol, LDL-Cholesterol, and VLDL-Cholesterol and Triglycerides in Healthy Iranian Ahvaz Population     

Mohammad Taha Jalali  Abdolhosain Mosavi Honomaror  Abdolkarim Rekabi  Mahmod Latifi 《Indian journal of clinical biochemistry : IJCB》2013,28(3):277-282

Cardiovascular diseases (CVD) are recognized as major mortality causes and imposes tremendously heavy socio-economic burden worldwide. A vast variety of risk factors have been introduced in the literature known to enhance the incidence of CVD, such as hyperlipidemia. Therefore in order to make an accurate clinical decision it is essential to have appropriate reference ranges for lipids and lipoprotein particles in a particular population. Healthy female (n = 601) and male (n = 617) cases were randomly selected according to certain exclusion criteria from individuals visiting the major University hospital clinics situated in different part of Ahvaz city, Iran, from June 2010 to December 2010. Fasting blood samples (10 ml) were collected and analyzed for total cholesterol, total triglyceride and HDL-C employing enzymatic assays of CHOD-PAP, GPO-PAP and homogenous methods respectively. The samples were obtained such to include the ethnic populations of Persian, Arab. Lore leaving in this city. The data were analyzed statistically by SPSS-18 software. The obtained results were analyzed then age ethnic-wise and reference ranges (mean ± 1SD) were calculated. Remarkable differences between the obtained results for our population with other nations were seen. Also ethnic difference for HDL-C among our cases was noted. The observed significant differences among different nations and ethnicities emphasizes the need for nation-specific, local reference ranges for lipids and lipoproteins particles, to be established.  相似文献   

Structuring collaboration in mixed-ability groups to promote verbal interaction,learning, and motivation of average-ability students     

Mohammad Saleh  Ard W. LazonderTon de Jong 《Contemporary educational psychology》2007

Average-ability students often do not take full advantage of learning in mixed-ability groups because they hardly engage in the group interaction. This study examined whether structuring collaboration by group roles and ground rules for helping behavior might help overcome this participatory inequality. In a plant biology course, heterogeneously grouped fourth-grade boys (n=164) were randomly assigned to a structured collaboration condition or an unconstrained comparison condition. Results indicated positive effects of structured collaboration on average-ability students’ achievement, motivation, and contribution to the group interaction. Another positive result was that structuring collaboration did not lower the scores of the high and low-ability students on these measures.  相似文献   

Argumentation-Based Computer Supported Collaborative Learning (ABCSCL): A synthesis of 15 years of research     

Omid Noroozi  Armin Weinberger  Harm J.A. Biemans  Martin Mulder  Mohammad Chizari 《Educational Research Review》2012,7(2):79-106

Learning to argue is an essential objective in education; and online environments have been found to support the sharing, constructing, and representing of arguments in multiple formats for what has been termed Argumentation-Based Computer Supported Collaborative Learning (ABCSCL). The purpose of this review is to give an overview of research in the field of ABCSCL and to synthesize the findings. For this review, 108 publications (89 empirical studies and 19 conceptual papers) on ABCSCL research dating from 1995 through 2011 were studied to highlight the foci of the past 15 years. Building on Biggs’ (2003) model, the ABCSCL publications were systematically categorized with respect to student prerequisites, learning environment, processes, and outcomes. Based on the quantitative and qualitative findings, this paper concludes that ABCSCL environments should be designed in a systematic way that takes the variety of specific conditions for learning into account. It also offers suggestions for educational practice and future research.  相似文献   

Online discussion compensates for suboptimal timing of supportive information presentation in a digitally supported learning environment     

Omid Noroozi  Maria C. Busstra  Martin Mulder  Harm J. A. Biemans  Hilde Tobi  Anouk Geelen  Pieter van’t Veer  Mohammad Chizari 《Educational technology research and development : ETR & D》2012,60(2):193-221

This study used a sequential set-up to investigate the consecutive effects of timing of supportive information presentation (information before vs. information during the learning task clusters) in interactive digital learning materials (IDLMs) and type of collaboration (personal discussion vs. online discussion) in computer-supported collaborative learning (CSCL) on student knowledge construction. Students (N = 87) were first randomly assigned to the two information presentation conditions to work individually on a case-based assignment in IDLM. Students who received information during learning task clusters tended to show better results on knowledge construction than those who received information only before each cluster. The students within the two separate information presentation conditions were then randomly assigned to pairs to discuss the outcomes of their assignments under either the personal discussion or online discussion condition in CSCL. When supportive information had been presented before each learning task cluster, online discussion led to better results than personal discussion. When supportive information had been presented during the learning task clusters, however, the online and personal discussion conditions had no differential effect on knowledge construction. Online discussion in CSCL appeared to compensate for suboptimal timing of presentation of supportive information before the learning task clusters in IDLM.  相似文献   

Green roofs for storm water management: a review     

ANWAR Mohamm  RASUL Mohammad G  KHAN Masud M. K 《重庆大学学报(英文版)》2012,11(1):5-11

The rapid urbanization and industrialization involve an unsustainable use of natural systems,leading to various problems in cities.The urban hydrological system experiences fluctuating amount of surfac...  相似文献   

Quality assurance strategies for affiliated institutions of HE: a case study of the affiliates under National University of Bangladesh   总被引：1，自引：0，他引：1  

Gazi Mahabubul Alam  Pradip Kumar Mishra  Mirja Mohammad Shahjamal 《Higher Education》2014,68(2):285-301

Presently, education is considered as the main weapon for national development. However, this tenet has been challenged by several economists. Their findings give rise to a further question: whilst expansion of education increases globally, what is it exactly that continues to hinder a country’s progression? There is no short answer, but one major area of concern is the quality and relevance of the education available. Research for this paper, the first of its kind in Bangladesh, has been carried out by interviews and observation in the affiliates of the National University of Bangladesh, where 80 % of the students in higher education are the underprivileged. The findings show that the legislators ignore the fact that quality of education in the affiliates is perceived as important.  相似文献