8,512 research outputs found
Analytical method for designing grating compensated dispersion-managed soliton systems
This paper was published in Journal of Optical Society of America B and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://www.opticsinfobase.org/abstract.cfm?URI=JOSAB-21-4-706. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law. © 2004 The Optical Society.Peer reviewedPublisher PD
BIRD CLASSIFICATION IN NOISY ENVIRONMENTS: THEORY, RESULTS AND COMPARATIVE STUDIES
Bird classification plays an important role in minimizing collisions between birds and aircraft. It is a challenging task to perform the sound-based classification correctly in a noisy environment. This paper addresses robust techniques that can improve the classification of bird in noisy environments. A complete recognition system is described and evaluated on a bird sound database containing 1547 bird sound files, with 11 bird species. Two types of features were extracted from the sound files: Mel Frequency Cepstral Coefficient (Mfcc) and RelAtive SpecTrAl (RASTA). Also, two statistical classifiers were developed using Gaussian Mixture Models (GMM) and Hidden Markov Models (HMM), respectively. The performance of these features and models are compared. Very good recognition rates (97% for clean data and 92% for 5dB signal-to-noise ratios) have been achieved when proper feature and model were selected
BIRD CLASSIFICATION IN NOISY ENVIRONMENTS: THEORY, RESULTS AND COMPARATIVE STUDIES
Bird classification plays an important role in minimizing collisions between birds and aircraft. It is a challenging task to perform the sound-based classification correctly in a noisy environment. This paper addresses robust techniques that can improve the classification of bird in noisy environments. A complete recognition system is described and evaluated on a bird sound database containing 1547 bird sound files, with 11 bird species. Two types of features were extracted from the sound files: Mel Frequency Cepstral Coefficient (Mfcc) and RelAtive SpecTrAl (RASTA). Also, two statistical classifiers were developed using Gaussian Mixture Models (GMM) and Hidden Markov Models (HMM), respectively. The performance of these features and models are compared. Very good recognition rates (97% for clean data and 92% for 5dB signal-to-noise ratios) have been achieved when proper feature and model were selected
The Radon Monitoring System in Daya Bay Reactor Neutrino Experiment
We developed a highly sensitive, reliable and portable automatic system
(H) to monitor the radon concentration of the underground experimental
halls of the Daya Bay Reactor Neutrino Experiment. H is able to measure
radon concentration with a statistical error less than 10\% in a 1-hour
measurement of dehumidified air (R.H. 5\% at 25C) with radon
concentration as low as 50 Bq/m. This is achieved by using a large radon
progeny collection chamber, semiconductor -particle detector with high
energy resolution, improved electronics and software. The integrated radon
monitoring system is highly customizable to operate in different run modes at
scheduled times and can be controlled remotely to sample radon in ambient air
or in water from the water pools where the antineutrino detectors are being
housed. The radon monitoring system has been running in the three experimental
halls of the Daya Bay Reactor Neutrino Experiment since November 2013
Graft Suturing for Lenticule Dislocation after Descemet Stripping Automated Endothelial Keratoplasty
Purpose: To report the mid-term outcomes of graft suturing in a patient with lenticule dislocation after Descemet stripping automated endothelial keratoplasty (DSAEK).
Case Report: A 78-year old woman was found to have graft dislocation involving the nasal half of the cornea after uneventful DSAEK. Graft repositioning, refilling the anterior chamber with air, and placement of four full-thickness 10/0 nylon sutures over the detached area were performed two weeks after the initial surgery. The sutures were removed 6 weeks later. Serial specular microscopy and anterior segment optical coherence tomography were performed. At 18 months, there was good lenticule apposition and a clear graft.
Conclusion: Anchoring sutures seem to be effective for management of graft detachment following DSAEK
Using Spreadsheets to Facilitate Committee Discussions and to Assist Committee Decisions in an Academic Setting: A Case Study
This paper is a case study on using spreadsheet tools to reduce the reliance on various manual tasks for committee work in an academic setting. Four types of tasks are covered. One of them is to establish collective preference rankings of candidates; it pertains to various committees. The remaining types are for graduate admissions. The coverage includes conversions of alternative test scores as achieved by individual applicants, a special case of university quality assessments, and record keeping in a rolling admission process. It is hoped that this paper can serve as a catalyst to generate interests among readers in exploring innovative ways to use spreadsheet tools in their own work settings.
This paper is a case study on using spreadsheet tools to reduce the reliance on various manual tasks for committee work in an academic setting. Four types of tasks are covered. One of them is to establish collective preference rankings of candidates; it pertains to various committees. The remaining types are for graduate admissions. The coverage includes conversions of alternative test scores as achieved by individual applicants, a special case of university quality assessments, and record keeping in a rolling admission process. It is hoped that this paper can serve as a catalyst to generate interests among readers in exploring innovative ways to use spreadsheet tools in their own work settings
Addendum to a Case Study on Using Spreadsheets to Facilitate Committee Discussions and to Assist Committee Decisions in an Academic Setting: Graduate Admissions of Applicants with Degrees from Chinese Universities
This paper updates an Excel-based example in a recent case study published in Spreadsheets in Education. The original example was intended to assist graduate admission committees outside China in assessing the academic quality of individual Chinese universities in the application files. China being the top country of origin of international students in many English-speaking countries, the official implementation of China's Double First-Class Initiative (DFCI) in 2017, aimed at improving the global recognition of Chinese universities, has provided valuable additional information for such committees to consider. The additional information includes not only the names of all designated universities in two different categories, but also the corresponding discipline or disciplines in each university for existing strengths or future potentials. As an addendum to the original example, this paper first justifies the update. It then shows how publicly available information under the DFCI can be organized in an Excel setting for improving the original example
A Regression-Based Interpretation of the Inverse of the Sample Covariance Matrix
The usefulness of covariance and correlation matrices is well-known in various academic fields. Matrix inversion, if required in an analytical setting, tends to mask the intuition in interpreting the corresponding empirical or experimental results. Drawing on the finance literature in mean-variance portfolio analysis, this paper presents pedagogically a regression-based interpretation of the inverse of the sample covariance matrix. Microsoft ExcelTM plays an important pedagogic role in this paper. The availability of various Excel functions and computational tools for numerical illustrations provides flexibility for instructors in the delivery of the corresponding analytical materials
Solving the Black-Scholes Partial Differential Equation via the Solution Method for a One-Dimensional Heat Equation: A Pedagogic Approach with a Spreadsheet-Based Illustration
The derivation of the Black-Scholes option pricing model, if covered in detail, is by far the most complicated among all major models in the finance curriculum. This paper presents a pedagogic approach to solve the Black-Scholes partial differential equation via the solution method for a one-dimensional heat equation. It is intended to help finance students with backgrounds in traditional business disciplines strengthen their understanding of the model derivation, without being distracted by the advanced mathematical requirements. Excel plays an important pedagogic role in this paper. The Excel illustration here not only confirms numerically some key features of the model derivation, but also connects the derived Black-Scholes formula and results from two key intermediate steps in the model derivation, thus making the analytical materials involved much easier to follow
- …