BEA: An efficient Bayesian emulation-based approach for probabilistic seismic response

This paper presents an advanced Bayesian emulation-based approach (hereafter BEA) that allows a reduced number of analyses to be carried out to compute the probabilistic seismic response and fragility of buildings. The BEA, which is a version of kriging, uses a mean function as a first approximation of the expected Engineering Demand Parameter given Intensity Measure (EDP|IM) and then models the approximation errors as a Gaussian Process (GP). A main advantage of the BEA is its flexibility, as it does not impose a fixed mathematical form on the EDP|IM relationship (unlike other approaches such as the standard cloud method). In addition, BEA makes fewer assumptions than standard methods, and provides improved characterization of uncertainty. This paper first presents the BEA approach and then assesses its computational efficiency as compared to the standard cloud method. This is done through the creation of EDP|IM relationships and fragility functions using the outputs of nonlinear dynamic and nonlinear static analyses for two case-study buildings representing Pre- and Special-Code seismic vulnerability classes. The nonlinear dynamic and static analysis methods represent different levels of accuracy i.e., are of high and low fidelity, respectively. The BEA and standard cloud methods are compared in their ability to recreate three “pseudo-realities”, each represented by an artificially generated EDP|IM relationship derived from a large set of analysis runs. Several input configurations are tested, including, reduced sets of training inputs (analysis runs), training inputs of high and low fidelity, two sampling processes for these inputs (i.e., random and stratified sampling) and two different IM representations. The results demonstrate that BEA yields both an improved accuracy in terms of mean estimates, as well as smaller uncertainty bounds compared to the cloud method. The improved performance of the BEA is maintained for all “pseudo-realities” tested regardless of whether it is trained with high or low fidelity analysis data, with the improvement particularly pronounced in cases when the advanced IM INp is used. It is demonstrated that good accuracy can be achieved with BEA even with reduced samples, yielding a saving in 25% in number of analyses required to generate the EDP|IM relationship. Finally, the use of BEA drastically improves both the accuracy and efficiency of the resultant seismic fragility functions

A microcontroller based voltage space vector modulator suitable for induction motor drives

Pulse width modulation techniques (PWM), introduced two decades ago, are the most used methods to control the voltage and frequency supplied to electrical AC machines. This paper describes a pulse width modulator based on the voltage space vectors technique that accepts voltage demands in dq coordinates and generates three phase PWM waveforms to drive a variable frequency voltage source inverter. A scheme based on a high performance 16 bit standard microcontroller with minimum of additional hardware is used, which allows a flexible and economical solution. The output frequency of the modulator can be varied in a large range and with a good resolution. Experimental data obtained from an induction motor drive will be presented.(undefined

Hubungan Status Gizi Siswa dengan Hasil Belajar Penjasorkes pada Siswa Kelas V Sdn 010 Beringin Jaya Kecamatan Sentajo Raya

, The problem in this research is learning outcome students are below a minimum learning competency standards (KKM) and the majority of the number of students is not far above the KKM. It may be caused by nutritional status possessed by the students. The purpose of this study was to determine the corelation of the nutritional status of students with the penjasorkes learning outcome students class V of SDN 010 Beringin Jaya District of Sentajo Raya. This research is correlational with a total sample of 35 people. Based on the research that has been conducted on class V SDN 010 Beringin Jaya District of Sentajo Raya obtained r = 0.514 medium category. Tests of significance using the formula t test Significance. From the calculation results are known t = 3.44, while t table = 1.679 so t = 3.44> t table = 1.679. That Hypothesis (Ho) rejected that reads: There is no significant corelation between the nutritional status of students (X) with the penjasorkes learning outcomes (Y). Based on the analysis of data obtained by the correlation coefficient of r = 0.514 where or significance was tested by t test and obtained t count equal to 3.44 means thitung> t table (1,679) thus Ha received, so it can be concluded there is a corelation the nutritional status of students with penjasorkes learning outcomes on class V SDN 010 Beringin Jaya District of Sentajo Raya

Mapping the Corporate Blogosphere: Linking Audience, Content, and Management to Blog Visibility

Blogs have been a common part of the Web for many years. Individuals create most blogs for their own purposes, but corporations have also begun to develop corporate blogs as a means for communicating with their stakeholders (e.g., customers, partners, investors). In this paper, we extend theory by generating what Gregor (2006) would call a type I theory. Specifically, we develop a theoretical framework for classifying and analyzing corporate blogs that examines blogs’ target audience, their content (focus and function), and how one should manage them. We use this framework to analyze the impact of these characteristics on the visibility of blogs operated by a sample of Fortune 500 companies. Our results show that a blog’s target audience and how its content and management fit with this audience can have significant impacts on blog visibility. We believe this framework provides a useful foundation for studying corporate blogs in the future

Dynamic wet etching of silicon through isopropanol alcohol evaporation

In this paper, Isopropanol (IPA) availability during the anisotropic etching of silicon in Potassium Hydroxide (KOH) solutions was investigated. Squares of 8 to 40 m were patterned to (100) oriented silicon wafers through DWL (Direct Writing Laser) photolithography. The wet etching process was performed inside an open HDPE (High Density Polyethylene) flask with ultrasonic agitation. IPA volume and evaporation was studied in a dynamic etching process, and subsequent influence on the silicon etching was inspected. For the tested conditions, evaporation rates for water vapor and IPA were determined as approximately 0.0417 mL/min and 0.175 mL/min, respectively. Results demonstrate that IPA availability, and not concentration, plays an important role in the definition of the final structure. Transversal SEM (Scanning Electron Microscopy) analysis demonstrates a correlation between microloading effects (as a consequence of structure spacing) and the angle formed towards the (100) plane.This work was supported by FCT (Fundação para a Ciência e Tecnologia) in the scope of the project PTDC/EBB-EBI/120334/2010 and by FEDER funds through the “Eixo I do Programa Operacional Fatores de Competitividade” (POFC) QREN, project reference COMPETE: FCOMP-01-0124-FEDER-020241. First author thanks FCT for scholarship grant SFRH/BD/74975/2010. INESC-MN and acknowledges Pest-OE/CTM/LA0024/2011 project

Autofluorescence spectroscopy of a human gastrointestinal carcinoma cell line - design of optical sensors for the detection of early stage cancer

Human tissues show autofluorescence (AF) emission spectra when excited by ultraviolet or shortwavelength visible light. The intensity and shape of these spectra are dependent on the tissues pathological state and, therefore, its measurement gives information about the degree of malignant transformations that could lead to cancer. In this article, it is characterized the AF spectra of one human gastrointestinal carcinoma cell line (CACO-2). The obtained results showed significant AF signal for the presence of amino acids. The spectral information obtained can be used for the design of fluorescence optical sensors that will be incorporated on an endoscopic capsule, for measuring the AF emission spectra of normal and cancer cells. This integrated optical system will innovate on the diagnosis of early stage cancer

A tunable Fabry-Perot optical filter for application in biochemical analysis of human’s fluids

This paper reports a Fabry-Perot tunable optical filter for application in clinical analysis, especially to measure the concentration of biochemical substances in biological fluids. Its tunable characteristics enable the measurement of different biochemical substances with the same device. It is composed of two parallel thin silver mirrors with a β-PVDF (Poly(Vinylidene Fluoride) in its β phase) film in-between as the resonance cavity. The filter is tuned by adjusting the space between the mirrors through an electric voltage inducing dipolar orientation in the β-PVDF film. Once the thickness changes of the β-PVDF film is due to variations at a molecular level, the changes are rather homogeneous within the samples. As a result, this approach achieves parallelism between the two mirrors, which is a complex problem to solve in conventional Fabry-Perot optical filters. Moreover, compared with an array of non-tunable optical filters with different cavity lengths, usually used to solve the parallelism problem, this device has a reduced area, its fabrication process is easier and it covers a wider spectral range. In addition, when used as a part of a biological fluids analysis system, it avoids the need for expensive optics and enables low-cost and portable devices, which would improve the use of spectrophotometric analysis in clinical diagnostics.R&D Centro Algoritmi da Universidade do Minho.Escola de Engenharia da Universidade do Minho - program IN2TEC.Fundação para a Ciência e a Tecnologia (FCT) - Grant POCI/CTM/59425/2004

Fluorescence and diffuse reflectance spectroscopy for early cancer detection using a new strategy towards the development of a miniaturized system

This paper describes the design of a miniature, cost-effective spectroscopy system for assessing tissue biochemical and morphological information using a few wavelengths. This instrument will integrate thin-film optical filters and silicon photodiodes, avoiding the use of a spectrograph and optical fibers. The components in the set-up design are described. The feasibility of using only 16 wavelengths to accurately extract tissue properties is confirmed on physical tissue models. Also, the suitable spectral performance of several optical filters for the selection of these wavelengths is demonstrated. The small size of this device will enable implementation in an endoscopic capsule.This research was supported by the Portuguese Foundation of Science and Technology and the MIT|Portugal Program (SFRH/BD/38978/2007