The intelligent browser for texpros

Browsing is a technique, which helps users to formulate their query and retrieve information in the information retrieval system. This technique provides users with capabilities of understanding their information needs and gaining system knowledge during the course of the browsing and thus it eases the users\u27 burden when issuing queries. The basic components of the browser provides an underlying structure which allows users to navigate and a browsing process controller which provides users with the needed assistance during each browsing session. In this dissertation, a new infrastructure (OP-Net), transformed from the existing object network is proposed. Each object in the object network is transformed into a predicate-augmented information repository. The predicate associated with each information repository governs the content of relevant documents in the depository during the browsing process and is updated continuously according to queries given by the user. The OP-Net with the relevant information repositories provides a dynamic and efficient environment for browsing. A new ranking model is also proposed based on the signature of the documents and the user\u27s query. The signature of a document is a document representative which utilizes the information provided by the dual model in TEXPROS (TEXt PROcessing System). With the signatures, the similarity of the document and the query can be computed, and the ranks of the documents can be derived. This dissertation describes a three-layer architecture for the browser. At the top layer, the browsing process controller conducts and monitors the browsing process, and utilizes the services provided by the service providers. At the bottom of this architecture is the storage management system which stores the documents and then associated frame instances and responses to the requests from the service providers in the second layer. This architecture supports the principle of information hiding by allowing the change of the design of each component without changing the others. In the conclusion of this dissertation, the potential improvements and future research will be proposed

Do Institutional Investors Exploit Market Anomalies? New Evidence from Alternative Mutual Funds

This paper investigates the anomaly trading behavior of a sample of mutual funds mimicking hedge fund strategies, namely alternative mutual funds (AMFs), based on both of their long and short equity positions. We document that AMFs trade on anomalies by buying underpriced stocks and short-selling overpriced peers. While AMFs’ buys and sells based on their long positions do not generate superior performance, their short-selling and covering activity based on their short positions significantly negatively predicts future abnormal returns. However, this predictability is mainly attributed to size and the nine anomaly characteristics considered. Overall, the results suggest that AMFs are sophisticated investors and that their short positions are more informative relative to their long positions

Synthesis and crystal structure of the first 6a-thiathiophthen metal complex [Mo(CO)_5PPh_(2]2)(µ-C_5H_2S_3)

The first 6a-thiathiophthen metal complex was prepared by treating M(CO_)5[PPh_2CS_2CH_2C≡CH] with a catalytic amount of secondary amine or tertiary amine; the structure of the 6a-thiathiophthen molybdenum complex is confirmed by an X-ray diffraction analysis

Adaptive MAP Selection with Load Balancing Mechanism for the Hierarchical Mobile IPv6

[[abstract]]The Hierarchical Mobile IPv6 (HMIPv6), which is drawn up by the IETF (Internet Engineering Task Force), utilizes the Mobile Anchor Point (MAP) to reduce the considerable number of binding update (BU) messages among the mobile node (MN), the correspondent node (CN), and the home agent (HA). According to the HMIPv6 mechanism, the MAPof higher layer can efficiently reduce the frequency of performing binding update; the higher loading of service is the bottleneck of the whole network. Because the bandwidth of the MAP which can serve is finite, the whole network will be crashed due to the overloading if the MAPserves as the gateway at the same time. This paper proposes a MAP selection mechanism that takes the mobile node's particular characteristics which include the mobility velocity and quantity of communication services into consideration, the proposal can manage the MAPs efficiently. Besides, we design aMAPload balancing mechanism to avoid the network crash due to the overloaded MAP.[[notice]]補正完畢[[incitationindex]]EI[[booktype]]紙

Electrokinetic trapping of biomolecules : novel nanofluidic devices for proteomic applications

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.Includes bibliographical references (p. 135-141).Sample preparation has long been the most important and costly process in bioanalyses. Conventional identification methods involve multiple purification steps combined with mass spectrometry or immunosensing. While well-developed and widely utilized, these methods require extensive human labor and exhibit limited resolving power for low abundance analytes. Due to the shear complexity and abundance variation of biosamples, rapid and ultra-sensitive diagnostic measurements of disease markers are still out of reach. To address this issue, we developed a novel nanofluidic concentrator, utilizing the unique concentration polarization effect of sub 50 nm nanofluidic filters. With the distinct ionic and molecular interaction at the nanoscale, nanofluidic systems can potentially outperform current sample preparation and molecular detection techniques. Aiming to investigate and expand the applications of these techniques, this thesis work involves the design and development of a highly efficient nanofluidic preconcentrator, which can achieve a million fold detectability enhancements without complex buffer arrangements. This thesis also includes an integrated preconcentration-immunosensing device.(cont.) By manipulating analyte concentrations, this integrated device not only increases the detection sensitivity, but also expands the dynamic range of given antibody-antigen couples. In addition, we also investigated the ion transfer at the micro-/nano-fluidic interface. Depending on the strength of the applied electric field across the nanochannel array, various phenomena such as concentration polarization, charge depletion, and nonlinear electrokinetic flows in the adjacent microfluidic channel can be observed and studied in situ by fluorescent microscopy. In summary, the nanofluidic concentrator we developed in this thesis facilitates sample preparation and detection of biomolecules from complex biological matrices and facilitates a further understanding of nanoscale molecular/fluid/ion transport phenomena by providing a well-controlled experimental platform.by Ying-Chih Wang.Ph.D

On-chip multi-dimensional biomolecule separation using multi-layer microfabricated valves

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.Includes bibliographical references (p. 89-94).Recent proteomics researches require a sensitive, high-speed, and automatic protein separation tool that far exceeds the capability of traditional two dimensional (2D) protein gel electrophoresis. Methods are described to achieve multi-dimensional biomolecule separation in a microfluidic channel. The new methods couple isoelectric focusing (IEF) with high ionic strength capillary electrophoresis (CE) by active micro valve control in a microchip. Several experiments demonstrating independent 2D separation were performed, and critical parameters for better chip performance were identified; including channel passivation, electroosmosis control, IEF linearity control, and detection enhancement. The result can be used for the filtration of high-abundance proteins, which used to be done by affinity columns. Also, it can be used for much possible integration between different heterogeneous separation/analysis techniques such as IEF, polyacrylamide gel electrophoresis (PAGE), CE, reverse-phase chromatography, and mass spectrometry (MS).by Ying-Chih Wang.S.M

3D Magneto-Hydrodynamic Simulations of Parker Instability with Cosmic Rays

This study investigates Parker instability in an interstellar medium (ISM) near the Galactic plane using three-dimensional magneto-hydrodynamic simulations. Parker instability arises from the presence of a magnetic field in a plasma, wherein the magnetic buoyant pressure expels the gas and cause the gas to move along the field lines. The process is thought to induce the formation of giant molecular clouds in the Galaxy. In this study, the effects of cosmic-ray (CR) diffusion are examined. The ISM at equilibrium is assumed to comprise a plasma fluid and a CR fluid at various temperatures, with a uniform magnetic field passing through it in the azimuthal direction of the Galactic disk. After a small perturbation, the unstable gas aggregates at the footpoint of the magnetic fields and forms dense blobs. The growth rate of the instability increases with the strength of the CR diffusion. The formation of dense clouds is enhanced by the effect of cosmic rays (CRs), whereas the shape of the clouds depends sensitively on the initial conditions of perturbation.Comment: 4 pages, Computer Physics Communications 2011, 182, p177-17

Continuous epidermal growth factor receptor-tyrosine kinase inhibitor administration in primary lung adenocarcinoma patients harboring favorable mutations with controlled target lung tumors dose not hinder survival benefit despite small new lesions

AbstractBackgroundIn this study, we investigated the efficacy of continuous epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) administration in lung adenocarcinoma patients harboring favorable mutations regarding the progressive disease (PD) status with appearance of indolent new lesions.MethodsFrom June 2010 to October 2012, 102 patients with lung adenocarcinoma, harboring favorable EGFR mutations and treated with EGFR-TKI were analyzed. Definite new lesions were detected during EGFR-TKI therapy, even though the primary target tumors were controlled.ResultsOf the 102 patients, 57 continued and 45 discontinued EGFR-TKI therapy. The median overall survival was 529 days for the discontinuation group and 791 days for the continuation group (p = 0.0197). Median survival time after the discontinuation of EGFR-TKI was 181 days and 115 days in the discontinuation and continuation groups, respectively (p = 0.1776), whereas median survival time after the appearance of indolent new lesions was 204 days and 262 days, respectively (p = 0.0237).ConclusionContinuous EGFR-TKI administration in favorable EGFR-mutative lung adenocarcinoma patients with controlled primary tumors did not hinder the survival benefit, despite the appearance of new lesions