Fit Tables Research Articles

Implementation of a fully implantable middle-ear hearing device chip.

BACKGROUND AND OBJECTIVE:Recently, with the increase in the population of hearing impaired people, various types of hearing aids have been rapidly developed. In particular, a fully implantable middle ear hearing device (F-IMEHD) is developed for people with sensorineural hearing loss. The F-IMEHD system comprises an implantable microphone, a transducer, and a signal processor. The signal processor should have a small size and consume less power for implantation in a human body.METHODS:In this study, we designed and fabricated a signal-processing chip using the modified FFT algorithm. This algorithm was developed focusing on eliminating time delay and system complexity in the transform process. The designed signal-processing chip comprises a 4-channel WDRC, a fitting memory, a communication 1control part, and a pulse density modulator. Each channel is separated using a 64-point fast Fourier transform (FFT) method and the gain value is matched using the fitting table in the fitting memory.RESULTS AND CONCLUSION: The chip was designed by Verilog-HDL and the designed HDL codes were verified by Modelsim-PE 10.3 (Mentor graphics, USA). The chip was fabricated using a 0.18 m CMOS process (SMIC, China). Experiments were performed on a cadaver to verify the performance of the fabricated chip.

First-Order Optimal Line-of-Sight Guidance for Stationary Targets

� In this paper, an explicit optimal line-of-sight guidance law for second-order binomial control systems is derived in closed-loop without acceleration limit. The problem geometry is assumed in one dimension and the final time and final position are fixed. The formulation is normalized in three forms to give more insight into the design and performance analysis of the guidance law. The computational burden of the guidance law is reasonable for today's microprocessors; however curve fitting or look-up table may be used for the implementation of the second-order optimal guidance law. The performance of the second-order optimal guidance law is compared in normalized forms with zero-lag and first-order optimal guidance laws using third-, fourth-, and sixth-order binomial control systems with/without acceleration limit. Moreover, the effect of the final time, the equivalent time constant of the vehicle control system, the vehicle-to-target line-of-sight weighting factor in cost function, and acceleration limit are investigated. Normalized miss distance analysis shows that the miss distance of the second- order guidance law is smaller than the two mentioned schemes for small total flight times, especially with large maneuvering capability.

Relationship between Peak Wavelength and Dominant Wavelength of Light Sources Based on Vector-Based Dominant Wavelength Calculation Method

ABSTRACTCurve fitting and lookup table methods based on vector relationships are proposed to compute dominant wavelength (DW), which is used to characterize hue. A curve-fitting method using a DW–angle relationship is simple but not very accurate, with an error of about 1 to 2 nm. A lookup table method is proposed for higher precision. The methods have been applied to study the relationships between peak wavelength and DW for Gaussian models of light sources’ spectra. For Gaussian models, DW varies as full-width at half maximum (FWHM) increases from 5 to 500 nm, and the trends differ at different peak wavelengths. For purity, as peak wavelength changes from 430 to 530 nm, the purity’s decreasing rate monotonically increases with FWHM, whereas as peak wavelength changes from 530 to 680 nm, the purity’s decreasing rate monotonically decreases with FWHM. Peak wavelength contours and FWHM contours are drawn for determination of DW and purity. The results should be useful for estimating DW (hue) of the Gaussian models of light sources’ spectra, which can guide the spectral design of light sources.

Usefulness of acceptance testing information for component-based system maintenance

Component-based system (CBS) development usually involves adapting best-matched components and writing integration code to handle the mismatches between system-to-be needs and available components. CBS presents unique maintenance challenges as a system analyst focuses on integrating existing components to build a software application. The lack of detailed individual component specification has been a key area of concern in CBS development because of its impact on the maintenance phase of a CBS development life cycle. Recent research suggests that the framework for integrated test (Fit) helps to better comprehend systems. In this work, the author presents a study to investigate the usefulness of acceptance test cases (Fit tables) information, when used as a functional specification, during the maintenance process. The mean correct implementation percentage with and without Fit tables were 86.19 and 83.52, respectively. Similarly, the mean times for the Fit tables and without Fit tables were 46.5 and 45.73, respectively. The results show that acceptance test cases help improve the functional correctness of changes with a little more effort during the maintenance process of a CBS.

ANN-based energy reconstruction procedure for TACTIC [formula omitted]-ray telescope and its comparison with other conventional methods

The energy estimation procedures employed by different groups, for determining the energy of the primary γ-ray using a single atmospheric Cherenkov imaging telescope, include methods like polynomial fitting in SIZE and DISTANCE, general least square fitting and look-up table based interpolation. A novel energy reconstruction procedure, based on the utilization of Artificial Neural Network (ANN), has been developed for the TACTIC telescope. The procedure uses a 3:30:1 ANN configuration with resilient backpropagation algorithm to estimate the energy of a γ-ray like event on the basis of its image SIZE, DISTANCE and zenith angle. The new ANN-based energy reconstruction method, apart from yielding an energy resolution of ∼26%, which is comparable to that of other single imaging telescopes, has the added advantage that it considers zenith angle dependence as well. Details of the ANN-based energy estimation procedure along with its comparative performance with other conventional energy reconstruction methods are presented in the paper and the results indicate that amongst all the methods considered in this work, ANN method yields the best results. The performance of the ANN-based energy reconstruction has also been validated by determining the energy spectrum of the Crab Nebula in the energy range 1–16TeV, as measured by the TACTIC telescope.

Using acceptance tests as a support for clarifying requirements: A series of experiments

One of the main reasons for the failure of many software projects is the late discovery of a mismatch between the customers’ expectations and the pieces of functionality implemented in the delivered system. At the root of such a mismatch is often a set of poorly defined, incomplete, under-specified, and inconsistent requirements. Test driven development has recently been proposed as a way to clarify requirements during the initial elicitation phase, by means of acceptance tests that specify the desired behavior of the system. The goal of the work reported in this paper is to empirically characterize the contribution of acceptance tests to the clarification of the requirements coming from the customer. We focused on Fit tables, a way to express acceptance tests, which can be automatically translated into executable test cases. We ran two experiments with students from University of Trento and Politecnico of Torino, to assess the impact of Fit tables on the clarity of requirements. We considered whether Fit tables actually improve requirement understanding and whether this requires any additional comprehension effort. Experimental results show that Fit helps in the understanding of requirements without requiring a significant additional effort.

A power primer

One possible reason for the continued neglect of statistical power analysis in research in the behavioral sciences is the inaccessibility of or difficulty with the standard material. A convenient, although not comprehensive, presentation of required sample sizes is provided here. Effect-size indexes and conventional values for these are given for operationally defined small, medium, and large effects. The sample sizes necessary for .80 power to detect effects at these levels are tabled for eight standard statistical tests: (a) the difference between independent means, (b) the significance of a product-moment correlation, (c) the difference between independent rs, (d) the sign test, (e) the difference between independent proportions, (f) chi-square tests for goodness of fit and contingency tables, (g) one-way analysis of variance, and (h) the significance of a multiple or multiple partial correlation.

Modeling of lossy multiregion substrates in microelectronic circuits using time‐domain surface integral equations

AbstractIn this work, the electromagnetic modeling of multiregion, finite‐sized lossy substrates in microelectronic circuits is carried out utilizing time‐domain surface integral equations. To reduce the additional computational complexity in the implementation caused by the decaying “wake” of the Green's function in lossy media, the resulting temporal convolution is addressed by the creation and use of an a priori exponential fitting table for discrete distances through Prony's method. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 47: 68–73, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21084

Monte Carlo Based Null Distribution for an Alternative Goodness‐of‐Fit Test Statistic in IRT Models

Assessing the correspondence between model predictions and observed data is a recommended procedure for justifying the application of an IRT model. However, with shorter tests, current goodness‐of‐fit procedures that assume precise point estimates of ability, are inappropriate. The present paper describes a goodness‐of‐fit statistic that considers the imprecision with which ability is estimated and involves constructing item fit tables based on each examinee's posterior distribution of ability, given the likelihood of their response pattern and an assumed marginal ability distribution. However, the posterior expectations that are computed are dependent and the distribution of the goodness‐of‐fit statistic is unknown. The present paper also describes a Monte Carlo resampling procedure that can be used to assess the significance of the fit statistic and compares this method with a previously used method. The results indicate that the method described herein is an effective and reasonably simple procedure for assessing the validity of applying IRT models when ability estimates are imprecise.

A power primer.

One possible reason for the continued neglect of statistical power analysis in research in the behavioral sciences is the inaccessibility of or difficulty with the standard material. A convenient, although not comprehensive, presentation of required sample sizes is provided here. Effect-size indexes and conventional values for these are given for operationally defined small, medium, and large effects. The sample sizes necessary for .80 power to detect effects at these levels are tabled for eight standard statistical tests: (a) the difference between independent means, (b) the significance of a product-moment correlation, (c) the difference between independent rs, (d) the sign test, (e) the difference between independent proportions, (f) chi-square tests for goodness of fit and contingency tables, (g) one-way analysis of variance, and (h) the significance of a multiple or multiple partial correlation.

A power primer.

One possible reason for the continued neglect of statistical power analysis in research in the behavioral sciences is the inaccessibility of or difficulty with the standard material. A convenient, although not comprehensive, presentation of required sample sizes is provided here. Effect-size indexes and conventional values for these are given for operationally defined small, medium, and large effects. The sample sizes necessary for .80 power to detect effects at these levels are tabled for eight standard statistical tests: (a) the difference between independent means, (b) the significance of a product-moment correlation, (c) the difference between independent rs, (d) the sign test, (e) the difference between independent proportions, (f) chi-square tests for goodness of fit and contingency tables, (g) one-way analysis of variance, and (h) the significance of a multiple or multiple partial correlation.

A Mapping Table for Obtaining Plant Population Data

Researchers and managers aliie are placing greater emphasis on understanding the life history characteristics of plants. Basic demographic data, including patterns of recruitment, reproduction, and survival, are central to understanding plant population dynamics. Such information, in combination with the proper correlative data, allows prediction of changes in plant populations in response to environment, competition, herbivory, or other factors (Schalll984). Applied uses of these data are many and varied. For example, acquiring detailed life history information on rare and endangered plants can help managers devise strategies for insuring their preservation. Mapping tables are routinely used for collecting plant demographicdata (Moore and Chapman 1986, Mackand Pyke 1983, Mack and Harper 1977), but seldom is detailed methodology presented. We describe the construction and use of an acrylic mapping table designed for obtaining basic demographic information from plant populations. Our primary objective was to design and construct a table that would allow accurate and precise relocation of mapping quadrats and plants using acetate sheets as “maps.” The table differs slightly from others that have been described: (1) It was designed so that permanent mapping quadrats were relocated from the positions of permanent corner stakes marked on acetate sheets, rather than from fitting table legs over permanently set stakes. This eliminates the necessity of precise stake locations which is often impossible in rocky soils. (2) The table was built with easy-toadjust legs so that its surface could be quickly leveled on uneven