Adjustment Method (adjustment + method)

Distribution by Scientific Domains

Selected Abstracts

A development of the discontinuous deformation analysis for rock fall analysis

Jian-Hong Wu
Abstract Discontinuous deformation analysis (DDA), a discrete numerical analysis method, is used to simulate the behaviour of falling rock by applying a linear displacement function in the computations. However, when a block rotates, this linear function causes a change in block size called the free expansion phenomenon. In addition, this free expansion results in contact identification problems when the rotating blocks are close to each other. To solve this problem of misjudgment and to obtain a more precise simulation of the falling rock, a new method called Post-Contact Adjustment Method has been developed and applied to the program. The basic procedure of this new method can be divided into three stages: using the linear displacement function to generate the global matrix, introducing the non-linear displacement function to the contact identification, and applying it to update the co-ordinates of block vertices. This new method can be easily applied to the original DDA program, demonstrating better contact identification and size conservation results for falling rock problems than the original program. Copyright 2005 John Wiley & Sons, Ltd. [source]

Modelling Probabilities of Devaluations

ECONOMICA, Issue 281 2004
Gabriela Mundaca
I show why, when the realized rates of depreciation within the exchange rate band are regressed on a given information set and conditioned on (ex post) actual no realignment ( la drift adjustment), a ,peso problem' is still encountered. The reason is that the frequency of realignments in the data need not be the same as the frequency of the (even small) subjective probabilities that a realignment may take place. I suggest an alternative approach to solve the peso problem and provide consistent estimates. My estimates of the expected realignment rates are greater than the ones obtained using the drift adjustment method. [source]

Simply and reliably integrating micro heaters/sensors in a monolithic PCR-CE microfluidic genetic analysis system

Runtao Zhong
Abstract A novel fabrication process was presented to construct a monolithic integrated PCR-CE microfluidic DNA analysis system as a step toward building a total genetic analysis microsystem. Microfabricated Titanium/Platinum (Ti/Pt) heaters and resistance temperature detectors (RTDs) were integrated on the backside of a bonded glass chip to provide good thermal transfer and precise temperature detection for the drilled PCR-wells. This heater/RTD integration procedure was simple and reliable, and the resulting metal layer can be easily renewed when the Ti/Pt layer was damaged in later use or novel heater/RTD design was desired. A straightforward "RTD-calibration" method was employed to optimize the chip-based thermal cycling conditions. This method was convenient and rapid, comparing with a conventional RTD-calibration/temperature adjustment method. The highest ramping rates of 14C/s for heating and 5C/s for cooling in a 3-,L reaction volume allow 30 complete PCR cycles in about 33,min. After effectively passivating the PCR-well surface, successful ,-phage DNA amplifications were achieved using a two- or three-temperature cycling protocol. The functionality and performance of the integrated microsystem were demonstrated by successful amplification and subsequent on-line separation/sizing of ,-phage DNA. A rapid assay for Hepatitis B virus, one of the major human pathogens, was performed in less than 45,min, demonstrating that the developed PCR-CE microsystem was capable of performing automatic and high-speed genetic analysis. [source]

Influence of background and surround on image color matching

Lidija Mandic
Abstract In this article, the corresponding-color data for complex images reproduced on different media were obtained by simultaneous matching using an adjustment method. In our experiment printed color images and images displayed on a monitor were compared in different viewing conditions. The viewing condition varied in surround relative luminance and background. The experimental data show that surround relative luminance has little influence on color matching between printed and monitor images while changes in background modify color appearance. These results were used to evaluate different chromatic adaptation transforms (CAT). We found that for the same viewing conditions the SHARP transform shows the best agreement between the experimental and predicted data. SHARP transform can not predict accurately corresponding colors for blue and black regions. Therefore, we proposed new CAT that shows better characteristics than other transforms for cyan, green, and black colors and similar characteristics for other colors. 2007 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 17, 244,251, 2007 [source]

Estimating causal effects from observational data with a model for multiple bias

Michael Hfler
Abstract Conventional analyses of observational data may be biased due to confounding, sampling and measurement, and may yield interval estimates that are much too narrow because they do not take into account uncertainty about unknown bias parameters, such as misclassification probabilities. We used a simple, multiple bias adjustment method to estimate the causal effect of social anxiety disorder (SAD) on subsequent depression. A Monte Carlo sensitivity analysis was applied to data from the Early Developmental Stages of Psychiatry (EDSP) study, and bias due to confounding, sampling and measurement was modelled. With conventional logistic regression analysis, the risk for depression was elevated in the presence of SAD only in the older cohort (age 17,24 years at baseline assessment); odds ratio (OR) = 3.06, 95% confidence interval (CI) 1.64,5.70, adjusted for sex and age. The bias-adjusted estimate was 2.01 with interval limits of 0.61 and 9.71. Thus, given the data and the bias model used, there was considerably more uncertainty about the real effect, but the probability that SAD increases the risk for subsequent depression (OR > 1) was 88.6% anyway. Multiple bias modelling, if properly used, reveals the necessity for a better understanding of bias, suggesting a need to conduct larger and more adequate validation studies on instruments that are used to diagnose mental disorders. Copyright 2007 John Wiley & Sons, Ltd. [source]

A high-power Cartesian feedback transmitter including a compact inverted Doherty amplifier

Hanjin Cho
Abstract A high-power Cartesian feedback transmitter including a compact inverted Doherty amplifier is presented. The system efficiency was further improved using a bias line adjustment method for the compact inverted Doherty amplifier. After the bias line adjustment from a ,/4 line for the Doherty amplifier, a power-added efficiency (PAE) of 6.9% points was improved from 41.3 to 48.2% at an output power level of 45 dBm. The whole Cartesian feedback transmitter system exhibited an efficiency of 40% and an adjacent channel leakage ratio of-51 dBc at an output power of 45 dBm for 859 MHz band ,/4-DQPSK applications. 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 944,946, 2008; Published online in Wiley InterScience ( DOI 10.1002/mop.23265 [source]