Synthesis of polycyclic aromatics having unusual molecular architectures via cascade cyclization reactions of enyne -allenes

The C2-C6 Schmittel cyclization reaction of the benzannulated enyne-allenes provides an efficient synthetic pathway for the construction of a variety of polycyclic aromatics. By starting from truxenone, the cascade cyclization reactions furnished several unusual and congested polycyclic compounds. The in situ generated enyne-allenes are key intermediates in these cyclization reactions.;A new synthetic approach to 2,2\u27-disubstituted 1,1\u27-binaphthyls and related compounds was also successfully developed by using the benzannulated enediynes as precursors. These 1,1\u27-binaphthyls derivatives can serve as potential BINOL type ligands. The assembly of the enediynyl precursors from three separate aromatic fragments allows the possibility of placing a variety of functional groups at various positions of the 1,1\u27-binaphthyl system.;A 12-step non-pyrolytic synthetic pathway employing the Schmittel cyclization reactions has been developed, leading to a bowl-shaped polycyclic aromatic hydrocarbon (PAH) having a 54-carbon framework of the surface of C60 . Incorporating of sp3-carbons on the 54-carbon framework facilitates the connection of carbon atoms intramolecularly

A Simple Baseline for Travel Time Estimation using Large-Scale Trip Data

The increased availability of large-scale trajectory data around the world provides rich information for the study of urban dynamics. For example, New York City Taxi Limousine Commission regularly releases source-destination information about trips in the taxis they regulate. Taxi data provide information about traffic patterns, and thus enable the study of urban flow -- what will traffic between two locations look like at a certain date and time in the future? Existing big data methods try to outdo each other in terms of complexity and algorithmic sophistication. In the spirit of "big data beats algorithms", we present a very simple baseline which outperforms state-of-the-art approaches, including Bing Maps and Baidu Maps (whose APIs permit large scale experimentation). Such a travel time estimation baseline has several important uses, such as navigation (fast travel time estimates can serve as approximate heuristics for A search variants for path finding) and trip planning (which uses operating hours for popular destinations along with travel time estimates to create an itinerary).Comment: 12 page

Determinants and Impacts of the Relative Use of Depository Receipts and Euro Convertible Bonds by High-tech Corporations: An Empirical Study

This paper adopts Taiwan's high-tech companies as the sample to address and examine four new determinants of various foreign financing instruments and test their impacts on the issuing firms. Our empirical findings are consistent with the following notions. First, the firms with higher foreign holding and foreign investment will be likely to adopt foreign financing policy. Moreover, the firms with higher stock dividend payment in Taiwan will adopt both of ECB (Euro convertible bond) and DR (depository receipt). Firm managers with better education background will prefer DR. Second, the use of DR can effectively decrease the volatility of stock returns but also pronounce a negative influence on the mean of stock returns. In contrast, the use of ECB can effectively increase the mean but can not significantly decrease the volatility.

A Concentric-based Sleep Scheduling Scheme for Wireless Sensor Networks

[[abstract]]In Wireless Sensor Networks (WSNs), how to extend the lifetime is an important issue. Our research uses Sleeping Scheduling scheme which divides the network into many concentric layers and rotates sensors in different odd and even layers to sleep. By our scheme, we can balance the power consumption among all sensors and reduce power and transmission load of sensors near sink. Our research use Transmit Power Control (TPC) technique to control topology and divide concentric layers, and use the topology to transmit packets to sink. Finally, the performance of our scheme is better than other Sleeping Scheduling schemes in the simulations.[[sponsorship]]Tamkang University[[incitationindex]]EI[[conferencetype]]åé[[conferencetkucampus]]å°åæ ¡å[[conferencedate]]20150902~20150903[[booktype]]é»å­ç[[iscallforpapers]]Y[[conferencelocation]]Taipei, Taiwa

Dynamics of Rapidly Rotating Bose-Einstein Quantum Droplets

The work theoretically investigates the dynamics of trapped rapidly rotating Bose-Einstein droplets governed by the modified Gross-Pitaevskii equation with the inclusion of Lee-Huang-Yang nonlinear interaction. Mimicking the quantum Hall systems, the stationary properties of droplets are obtained by minimizing the energy functional established based on the Laughlin-like wavefunction including Landau-Level mixing. By tuning the particle-particle interaction and rotation speed, the preference of the formation of the center-of-mass state, vortex state, and off-centered vortex state can be distinguished on the phase diagram. Under fast rotations, the highly-spiral phase portraits reveal that the emergence of huge vortices with high angular momentum would stabilize the droplets against centrifugal depletion. By solving Euler-Lagrange equations, the periodicity and stability of each phase's breathing and trajectory during long-time evolution are analyzed. As a signature of superfluids, the generation of nonuniform persistent currents of multiple topological charges is also a direct reflection of dynamic breathing induced by the Landau-Level mixing effect