An urban light rail transport in the Middle East which is operated as a cyclic schedule on fixed Origin-Destination (O-D) pairs and two lines is considered. A high ridership is observed during ...weekends and peak hours, leading to severe over-crowding. To reduce over-crowding and alleviate congestions, three different strategic solutions are considered. (i) Reduce peak hour headways. (ii) Increase number of cabins in trains operated during peak hours. (iii) Increase number of services between modified O-D pairs with denser traffic. The problem domain is modelled as a directed transit network and further as an Linear-programming (LP) formulation with a focus on the third solution for one of the lines, under an assumption of known demand. Nodes represent arrival/departure times at each station and constraints on (i) consistency of flow, (ii) non-negativity of flow, (iii) indivisibility, (iv) demand satisfiability and (v) bounds are proposed. The objective is: (i) To minimize number of train cabins in the system; and (ii) to minimize the total car miles run by all trains in a schedule cycle. The LP Model developed for the third proposed solution is tested with actual data using an open LP Solver. Several interesting questions have arisen out of the proposed model. Attempts continue (i) to acquire, test and evaluate validated data from the operators, (ii) simulate the proposed model to one of the two operational lines and study congestion alleviation of both lines in a combined manner and (iii) evaluate the model against other possible solutions.
A highly integrated 1.75-GHz 0.35-/spl mu/m CMOS transmitter is described. The I/Q modulator-based transmitter facilitates integration through the use of a unique mixer, termed a harmonic-rejection ...mixer, and a wide loop bandwidth phase-locked loop (PLL) for the RF synthesizer. The harmonic-rejection mixers are used to eliminate the need for a discrete IF filter and the use of a wide loop bandwidth PLL allowed for the complete integration of the synthesizers using low-Q components while achieving low phase noise. The entire transmit signal path from the digital-to-analog converters to the power amplifier, including two fully integrated frequency synthesizers, is integrated into a single-chip solution. The transmitter was tested with a testing buffer before the power amplifier (PA) and achieved less than 1.3/spl deg/ rms phase error when modulating a DCS-1800 GMSK signal. The prototype consumed 151 mA from a 3-V supply. A class-C PA, capable of driving 25 dBm off-chip, was included and the output was compared to the testing buffer with little change in the transmitter performance.
We consider the design of convolutional codes and low density parity check (LDPC) codes with minimum-shift keying (MSK) when the receiver employs iterative decoding and demodulation. The main idea ...proposed is the design of coded schemes that are well matched to the iterative decoding algorithm being used rather than to hypothetical maximum-likelihood decoding. We first show that the design is crucially dependent on whether the continuous phase encoder (CPE) is realized in recursive form or in nonrecursive form. We then consider the design of convolutionally coded systems and low density parity check codes with MSK to obtain near-capacity performance. With convolutional codes, we show that it is possible to improve the performance significantly by using a mixture of recursive and nonrecursive realizations for the CPE. For low density parity check codes, we show that codes designed for binary phase shift keying are optimal for MSK only if the nonrecursive realization is used; for the recursive realization, we design new LDPC codes based on the concept of density evolution. We show that these codes outperform the best known codes for MSK and have lower decoding complexity.
Measurement-based quantum error correction relies on the ability to determine the state of a subset of qubits (ancillas) within a processor without revealing or disturbing the state of the remaining ...qubits. Among neutral-atom-based platforms, a scalable, high-fidelity approach to midcircuit measurement that retains the ancilla qubits in a state suitable for future operations has not yet been demonstrated. In this work, we perform maging using a narrow-linewidth transition in an array of tweezer-confined ^{171}Yb atoms to demonstrate nondestructive state-selective and site-selective detection. By applying site-specific light shifts, selected atoms within the array can be hidden from imaging light, which allows a subset of qubits to be measured while causing only percent-level errors on the remaining qubits. As a proof-of-principle demonstration of conditional operations based on the results of the midcircuit measurements, and of our ability to reuse ancilla qubits, we perform conditional refilling of ancilla sites to correct for occasional atom loss, while maintaining the coherence of data qubits. Looking toward true continuous operation, we demonstrate loading of a magneto-optical trap with a minimal degree of qubit decoherence.
A 1.75 GHz highly-integrated narrow-band complementary metal oxide semiconductors (CMOS) transmitter was proposed with harmonic-rejection mixers. The proposed architecture consists of two baseband ...signal paths, an image/harmonic rejection upconversion mixer, a channel-selection sysnthesiser, a fixed-frequency Rf synthesizer and two quadrature generation circuits. A prototype device based on the harmonic-rejection CMOS integrated circuit concept was fabricated in a 0.35 mu m, double-poly, 5-layer metal CMOS process. A breakdown of the power consumption and a summary of test results were described.
A WCF & WPF based Chat Application Narayanaswami, S; Yoon, D
Proceedings of the International Conference on e-Learning, e-Business, Enterprise Information Systems, and e-Government (EEE),
01/2017
Conference Proceeding
We present a chat system based on Windows Communication Foundation (WCF) and Windows Presentation Foundation (WPF) with emphasis on security aspects of WCF. As the name indicates, WCF lays down the ...foundation for the communication between server and client, while WPF is a graphical user interface system in .NET. Through the chat system, we explore the security measures implemented in X.509, which include the contracts, endpoints and the usage of the service. This is then presented by developing an application which implements the WCF security aspects in a client-server architecture and effectively handles the security. WCF provide a very rich and easy configurable environment to implement security. The client and server will communicate by using xml messages. WCF provides two mechanisms for transfer security which is transport security and message security. We will make use of these security mechanism provided by the WCF in our application. One common use of the WCF is to provide a way to distribute and collect data and information to and from multiple clients at the same time, with no hassle in the user experience on the client side. The four core security features that WCF addresses are Authentication, Authorization, Confidentiality, Integrity and auditing. WCF supports a variety of authentication options including user name, Windows, and certificate authentication which will be studied in detail.
Replacement of one triazole ring of fluconazole with 4-pyridinyl leads to an increase in activity against
Aspergillus fumigatus. Introduction of an α-methyl group has a marked additional beneficial ...effect. Investigation of pyridinyl and pyrimidinyl analogues resulted in the identification of
30 (UK-109, 496, voriconazole) which has excellent potency against a broad range of fungal pathogens including A.
fumigatus and Candida krusei.
Replacement of one triazole ring of fluconazole with 4-pyridinyl leads to an increase in activity against
Aspergillus fumigatus. Introduction of an α-methyl group has a marked additional beneficial effect. Investigation of pyridinyl and pyrimidinyl analogues resulted in the identification of
30 (UK-109,496, voriconazole) which has excellent potency against a broad range of fungal pathogens including
A. fumigatus and
Candida krusei.
Assembling and maintaining large arrays of individually addressable atoms is a key requirement for continued scaling of neutral-atom-based quantum computers and simulators. In this work, we ...demonstrate a new paradigm for assembly of atomic arrays, based on a synergistic combination of optical tweezers and cavity-enhanced optical lattices, and the incremental filling of a target array from a repetitively filled reservoir. In this protocol, the tweezers provide microscopic rearrangement of atoms, while the cavity-enhanced lattices enable the creation of large numbers of optical traps with sufficient depth for rapid low-loss imaging of atoms. We apply this protocol to demonstrate near-deterministic filling (99% per-site occupancy) of 1225-site arrays of optical traps. Because the reservoir is repeatedly filled with fresh atoms, the array can be maintained in a filled state indefinitely. We anticipate that this protocol will be compatible with mid-circuit reloading of atoms into a quantum processor, which will be a key capability for running large-scale error-corrected quantum computations whose durations exceed the lifetime of a single atom in the system.
PDF
