AN ONTOLOGY-BASED DOCUMENT RECOMMENDATION SYSTEM: DESIGN, IMPLEMENTATION, AND EVALUATION

With the explosion of information, more and more people are embarrassed to manage information effectively. How to search and retrieve accurate information match to people\u27s requirements has been an important issue in information management research. Although search engine can solve this problem partly, the support of manage information is still limited. To use search engine, the users should input precise keywords by themselves first and this stage might cause much confusion to users. For that reason, we need a recommendation system that can catch users\u27 preferences to help users to obtain information more quickly and conveniently without copious process. In our research, a recommendation system is designed based on users\u27 profile. We use ontology technology to be the core of our recommendation system, because ontology can describe the concepts and relations of individual\u27s domain knowledge. Formal Concept Analysis (FCA) algorithm is one of the most popular methods to build ontology, and we apply it to construct our experimental system to recommend master theses to subjects. In order to evaluate our recommendation system, we developed a FCA-based system and another Scoring FCA-based system as treatments, and a Keyword-based system as a control group. We focus on both users\u27 satisfaction on information quality and system quality of our systems. The results show that users have higher information satisfaction on Scoring FCA-based system and FCA-based system than Keyword-based system. This study contributes to research and practice in information recommendation system

Wealth Effects of Dividend Announcements on Bondholders: The Case of Taiwan Bond Market

Although bonds play an important role in U.S. capital markets, this financial instrument is less common in the emerging markets. Taiwan is a typical case. In fact, both bond issuances and bond transactions in Taiwan have been declining in the past years. Consistent with the previous studies, this research documents that wealth transfer effects exist between bondholders and stockholders. We hypothesize that this wealth transfer discourages investors from investing in bond markets because companies in Taiwan seem to care less about the interest of bondholders. Using the event study methodology, we examine the price change of bonds and stocks in Taiwan capital market around cash dividend announcements. We find that there are significant abnormal returns before cash dividend announcements from 30 days to 60 days and that there is insignificant price change of bonds during the three-day period around the announcement. Possible explanations of the results include low bond trading volumes, insider trading before announcements, and mixing signaling and wealth transfer effects. Although this study cannot prove that the results are directly related to management holdings, we tend to believe that insider trading somehow matters

Machine learning ensures rapid and precise selection of gold sea-urchin-like nanoparticles for desired light-to-plasmon resonance

Sustainable energy strategies, particularly solar-to-hydrogen production, are anticipated to overcome the global reliance on fossil fuels. Thereby, materials enabling the production of green hydrogen from water and sunlight are continuously designed,; e.g.; , ZnO nanostructures coated by gold sea-urchin-like nanoparticles, which employ the light-to-plasmon resonance to realize photoelectrochemical water splitting. But such light-to-plasmon resonance is strongly impacted by the size, the species, and the concentration of the metal nanoparticles coating on the ZnO nanoflower surfaces. Therefore, a precise prediction of the surface plasmon resonance is crucial to achieving an optimized nanoparticle fabrication of the desired light-to-plasmon resonance. To this end, we synthesized a substantial amount of metal (gold) nanoparticles of different sizes and species, which are further coated on ZnO nanoflowers. Subsequently, we utilized a genetic algorithm neural network (GANN) to obtain the synergistically trained model by considering the light-to-plasmon conversion efficiencies and fabrication parameters, such as multiple metal species, precursor concentrations, surfactant concentrations, linker concentrations, and coating times. In addition, we integrated into the model's training the data of nanoparticles due to their inherent complexity, which manifests the light-to-plasmon conversion efficiency far from the coupling state. Therefore, the trained model can guide us to obtain a rapid and automatic selection of fabrication parameters of the nanoparticles with the anticipated light-to-plasmon resonance, which is more efficient than an empirical selection. The capability of the method achieved in this work furthermore demonstrates a successful projection of the light-to-plasmon conversion efficiency and contributes to an efficient selection of the fabrication parameters leading to the anticipated properties

Bilateral Ureteral Leiomyoma With Bilateral Ureteropelvic Junction Obstruction

Leiomyomas are benign tumors characterized by overgrowth of visceral smooth muscle in the respiratory, gastrointestinal, and female reproductive tracts. They rarely develop in the urinary system and only 10 cases of unilateral ureteral leiomyoma (UL) have been reported since 1955. No cases of bilateral UL or ureteropelvic junction obstruction due to UL have ever been reported. We present a case of bilateral UL with bilateral ureteropelvic junction obstruction. To the best of our knowledge, this is the first such case report in the English literature

On the Improvement of Wiener Attack on RSA with Small Private Exponent

RSA system is based on the hardness of the integer factorization problem (IFP). Given an RSA modulus N=pq, it is difficult to determine the prime factors p and q efficiently. One of the most famous short exponent attacks on RSA is the Wiener attack. In 1997, Verheul and van Tilborg use an exhaustive search to extend the boundary of the Wiener attack. Their result shows that the cost of exhaustive search is 2r+8 bits when extending the Weiner's boundary r bits. In this paper, we first reduce the cost of exhaustive search from 2r+8 bits to 2r+2 bits. Then, we propose a method named EPF. With EPF, the cost of exhaustive search is further reduced to 2r-6 bits when we extend Weiner's boundary r bits. It means that our result is 214 times faster than Verheul and van Tilborg's result. Besides, the security boundary is extended 7 bits

5-Iodo­pyrimidin-2-amine

The mol­ecule of the title compound, C4H4IN3, has crystallographic mirror plane symmetry. In the crystal, the mol­ecules are connected through N—H⋯N hydrogen bonds into polymeric tapes extended along the a axis, which are typical of 2-amino­pyrimidines. Each mol­ecule acts as a double donor and a double acceptor in the hydrogen bonding

Splint therapy for disc displacement with reduction of the temporomandibular joint. Part I: Modified mandibular splint therapy

AbstractThe aims of this preliminary study were to present a modified mandibular splint together with a treatment regimen and to evaluate their effects on the treatment of reciprocal joint sounds of the temporomandibular joint (TMJ). The study participants were recruited from 312 consecutive patients in the temporomandibular disorder clinic of a medical center in Taiwan from January 2003 to December 2003. From among these, 59 cases with typical reciprocal clicking were selected for this study. All participants were treated with a modified mandibular splint and then followed up for 6 months. Successful treatment was defined as leading to the disappearance of the joint sounds of TMJ, as described by patients. Based on clinical evaluation, the overall success rate was 71.2% (42/59) with minimal temporary complications. Patients with clicking at less than 3.5cm of interincisal opening had a success rate of 92.5%, which was higher than the success rate of patients with clicking at a mouth opening of 3.5cm or more. This study showed that a modified mandibular splint can be used to treat reciprocal clicking of the TMJ effectively and encouraged us to conduct further study on the efficacy of this splint to treat disc displacement with reduction of TMJ using magnetic resonance imaging examination