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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Investigation of ICN Photodissociation Employing the Method of Fluorescence Imaging by Sliced Microscopy

Kwoung, Wen-tang 22 July 2005 (has links)
none
2

Sliced fluorescence imaging: a versatile method to study photo-induced dynamic processes

Chen, Yu-wei 08 September 2009 (has links)
To reduce the image blurring which originates from contributions of a cylindrical array of photolysis events in a photo-induced experiment, a variant of fluorescence imaging techniques has been developed to study photodissociation dynamics and collisional relaxation processes in the bulk. The experimental arrangement utilizes sliced imaging techniques of photofragments by the laser-induced fluorescence detection scheme. An unconventional procedure is employed to guide the photolysis laser in the viewing direction of the imaging detector with a proper obstruction. The sliced image in the direction perpendicular to the photolysis laser is equivalent to a two-dimensional projection of the fluorescence image of photoproducts from a single photolysis center. Experimental images of state-selected CN photofragments from the ICN photodissociation are presented to illustrate the versatility of the present method.
3

Imaging photodissociation of ICN: Employing the Method of Fluorescense Imaging by Sliced Microscopy

Chiu, Pei-lun 17 January 2007 (has links)
none
4

Spectrum-sliced incoherent light source for multi-channel WDM system

Hu, Chih-Jen 26 June 2000 (has links)
In this thesis, we propose a potentially inexpensive light source for the mulit-channel wavelength division multiplexing (WDM) system applications. The spectrum-sliced incoherent light source (SILS) is alternative conventional laser source for the WDM system owing to its simplicity and flexibility. However, the spectrum-sliced source suffers from the intensity noise and spontaneous-spontaneous beat noise. Thus, it is necessary to increase the optical bandwidth or decrease the electrical bandwidth (by varying the bit rate ) to improve the signal to noise ratio (SNR). We used the intra-channel four wave mixing (IC-FWM device) before the receiver to suppresses the intensity noise of the light source, thus greatly expands the optical bandwidth of the received signal. We not only demonstrated the capability of an 8 ¡Ñ 2.5 Gb/s, DWDM with 200 GHz channel spacing transmission system by utilizing only one spectrum-sliced source, but also investigate the cross-talk issue of SILS in the fiber Bragg grating-based optical add/drop multiplexer (FBG-based OADM) and the Mach-Zehnder fiber Bragg grating-based optical add/drop multiplexer (MZ FBG-based OADM) systems.
5

Nonlinear Residual Income Model

Yeh, Chao-Hui 30 July 2001 (has links)
Nonlinear Residual Income Model Abstract Residual income has been proven to be a new approach of value relevance recently. The purpose of this study is to introduces residual income completely, and hopefully make some creativeness and contribution to residual income model. This paper is a both modeling and empirical study. In modeling, we have the following results¡G (1) Next period residual income is a nonlinear function of this period residual income, when we consider managers¡¦ real option. (2) This study introduces ¡§nonlinear residual income model¡¨ into Ohlson model, therefore firms¡¦ value is a nonlinear function of this period residual income. (3) This paper develops an option-based valuation model. According to this paper, equity value consists of the expected value from maintaining current operations, plus the value of the (put) option to discontinue operations at date t+1, and value of the (call) option to expand operations at date t+1. Empirical tests based on 27,536 firm-year observations from 1991-99 supports the above predictions of (1) and (2). In addition to the traditional OLS, this paper applies a new statistical approach--Sliced Inversed Regression (SIR). By SIR, we identify that our data has nonlinear components. This paper provides an alternative choice of valuation model and suggests that future research should approach the basic of value drivers.
6

Race time prediction for Taiwan marathoner

Jiang, Cheng-Hong 19 July 2008 (has links)
Pete Riegel, a well-known sport expert, proposed the formula of race time prediction in 1977. This article discusses whether it is also suitable for Taiwan marathoners. We compiled two hundred and four effective datum by questionary. Some variables possible to affect the running result are added in this work, namely: sex, age, the year of run, height, weight, the race number of marathon, the quantity and the frequency of practices each week. Next, we use multiple regression and sliced inverse regression to increase the accuracy of the running time prediction. The best model, found here has eighty percentage's player with predictive error within fifteen minuates, which is better than the original model by Riegel(1977) with only having sixty-two percentages.
7

Evaluation of Thin-Slice Axial Magnetic Resonance Imaging on the Diagnostic Accuracy of Meniscus Tears

Albert, Andrew 28 March 2018 (has links)
A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine. / This investigation assessed the diagnostic accuracy of thin-slice (1mm) axial Magnetic Resonance Imaging (MRI) in the detection and classification of meniscal tears. Meniscal injuries are a common reason for knee pain and the use of MRI has become standard in their assessment. However, the classification of tears and not merely the detection of lesions has become increasingly important to surgeons in deciding between surgery and conservative management. There is a growing body of literature examining the utility of axial MR images in aiding radiologists to more accurately describe and classify morphological characteristics of meniscus tears. However, the thick- slice (4-5mm) axial sequences utilized at many institutions typically only produce 1-2 images on which the menisci can be visualized, which does not provide the required detail to accurately describe the morphological characteristics of meniscal lesions. This study adds to the growing body of literature examining the diagnostic capabilities of MRI with TSAi to accurately describe meniscal tear morphologies. Imaging reports from 107 patients with clinically suspected meniscus injuries who underwent MRI with thin-slice axial imaging were compared to arthroscopic findings using receiver operating characteris (ROC) analysis to assess the diagnostic accuracy of MRI with thin- slice axial imaging (TSAi). The sensitivity and specificity of MRI with TSAi for meniscal tear detection were found to be 91% and 37.5% respectively. Furthermore, MRI with TSAi was highly specific for bucket handle (98.5%) and root ligament tears (94.1%). The findings of our investigation indicate that MRI with TSAi may assist surgeons in determining the need for operative versus conservative management. MRI with TSAi may be particularly helpful in the case of root tears, which were not as readily identified with traditional MRI techniques and often require surgical intervention due to morbidity associated with unrepaired root tears.
8

Two-dimension to three-dimension conversion using sliced sections

Sholapurwalla, Ardeshir January 1991 (has links)
No description available.
9

Saddlepoint Approximation for Calculating Performance of Spectrum-Sliced WDM Systems

Teotia, Seemant 06 August 1999 (has links)
Spectrum slicing is a novel technique for the implementation of wavelength-division multiplexing (WDM). While conventional WDM systems employ laser diodes operating at discrete wavelengths as carriers for the different data channels that are to be multiplexed, spectrum-sliced systems make use of spectral slices of a broadband noise source for the different data channels, thus being economically attractive. In spectrum-sliced WDM systems with an optical preamplifier receiver there is an optimum m=BoT (Bo = optical channel bandwidth, T = bit duration) to minimize the average number of photons-per-bit (Np) required at the receiver for a given error probability (Pe). Both the optimum m and the minimum increase as interchannel interference increases. This has been analyzed previously by using the Gaussian approximation, or by assuming that the signals at the decision point are chi-square distributed. Although the chi-square distribution is valid in the case where there is no interference, it is not valid in the presence of interference, since the interference from the neighboring channel has a smaller bandwidth than the signal. In this thesis, a different method is used to analyze this problem. This method is called the Saddlepoint Approximation, and while the exact analysis required determination of the probability density function (pdf) of the received signal, the saddlepoint method makes use of moment generating functions (MGFs) which have a much simpler form and don't require the convolution operations the pdfs require. The saddlepoint method is validated by comparing results obtained with the chi-square analysis for the no interchannel interference case when a rectangular shaped filter is used. The effect of non-rectangular spectra on receiver sensitivity with the use of the Saddlepoint Approximation is also investigated. After verifying its validity, the method is applied to the interchannel interference case caused by filter overlap. It is shown that for small filter overlap, use of an equivalent chi-square distribution is valid, but when the overlap becomes larger, the performance approaches that calculated using the Gaussian distribution. It is shown that there is an optimum filter overlap to maximize the total system throughput when total bandwidth is constrained. Operating at this optimum, the total system throughput is 135 Gbits/s when the total system bandwidth is 4.4 THz (35 nm) for a Bit Error Rate (BER) of 10e-9. / Master of Science
10

Protein Structure Prediction Based on the Sliced Lattice Model

Wang, Chia-Chang 11 July 2005 (has links)
Functional expression of a protein in life form is decided by its tertiary structure. In the past few decades, a significant number of studies have been made on this subject. However, the folding rules of a protein still stay unsolved. The challenge is to predict the three-dimensional tertiary structure of a protein from its primary amino acid sequence. We propose a hybrid method combining homology model and the folding approach to predict protein three-dimensional structure from amino acid sequence. The previous researches on folding problem mostly take the HP (Hydrophobic-Polar) model, which is not able to simulate the native structure of proteins. We use a more exquisite model, the sliced lattice model, to approximate the native forms. Another essential factor influencing protein structures is disulfide bonds, which are ignored in the HP model. We use the ant colony optimization algorithm to approximate the folding problem with the constrained disulfide bond on the sliced lattice HP model. We show that the prediction results are better than previous methods by the measurement of RMSD(Root Mean Square Deviation).

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