26,893 research outputs found

    Prospect of China's Energy Investment in Southeast Asia under the Belt and Road Initiative: A Sense of Ownership Perspective

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    © 2019 Elsevier Ltd China's Belt and Road Initiative (BRI) has attracted the world's attention since it was proposed. This study focuses on the BRI in the energy sector in ASEAN. It examines the current status of China's investment into ASEAN's energy sector. It then discusses the problems of China's investment into the ASEAN energy sector with two cases in Myanmar. In addressing the problems and challenges, the study adopts a ‘sense of ownership’ framework to analyze how to improve the acceptability of the Chinese investment. It argues that the BRI priorities, including ‘people-to-people bond’, provide an opportunity to bring a sense of ownership to the community networking that is to be built as a key part of BRI and more profoundly, an opportunity to establish a good image and to make investment projects successful

    Theory of control of spin/photon interface for quantum networks

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    A cavity coupling a charged nanodot and a fiber can act as a quantum interface, through which a stationary spin qubit and a flying photon qubit can be inter-converted via cavity-assisted Raman process. This Raman process can be controlled to generate or annihilate an arbitrarily shaped single-photon wavepacket by pulse-shaping the controlling laser field. This quantum interface forms the basis for many essential functions of a quantum network, including sending, receiving, transferring, swapping, and entangling qubits at distributed quantum nodes as well as a deterministic source and an efficient detector of a single photon wavepacket with arbitrarily specified shape and average photon number. Numerical study of noise effects on the operations shows high fidelity.Comment: 4 pages, 2 figure

    An integrated bayesian approach for effective multi-truth discovery

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    Truth-finding is the fundamental technique for corroborating reports from multiple sources in both data integration and collective intelligent applications. Traditional truthfinding methods assume a single true value for each data item and therefore cannot deal will multiple true values (i.e., the multi-truth-finding problem). So far, the existing approaches handle the multi-truth-finding problem in the same way as the single-truth-finding problems. Unfortunately, the multi-truth-finding problem has its unique features, such as the involvement of sets of values in claims, different implications of inter-value mutual exclusion, and larger source profiles. Considering these features could provide new opportunities for obtaining more accurate truthfinding results. Based on this insight, we propose an integrated Bayesian approach to the multi-truth-finding problem, by taking these features into account. To improve the truth-finding efficiency, we reformulate the multi-truthfinding problem model based on the mappings between sources and (sets of) values. New mutual exclusive relations are defined to reflect the possible co-existence of multiple true values. A finer-grained copy detection method is also proposed to deal with sources with large profiles. The experimental results on three real-world datasets show the effectiveness of our approach.Xianzhi Wang, Quan Z. Sheng, Xiu Susie Fang, Lina Yao, Xiaofei Xu, Xue L

    Approximate truth discovery via problem scale reduction

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    Many real-world applications rely on multiple data sources to provide information on their interested items. Due to the noises and uncertainty in data, given a specific item, the information from different sources may conflict. To make reliable decisions based on these data, it is important to identify the trustworthy information by resolving these conflicts, i.e., the truth discovery problem. Current solutions to this problem detect the veracity of each value jointly with the reliability of each source for every data item. In this way, the efficiency of truth discovery is strictly confined by the problem scale, which in turn limits truth discovery algorithms from being applicable on a large scale. To address this issue, we propose an approximate truth discovery approach, which divides sources and values into groups according to a userspecified approximation criterion. The groups are then used for efficient inter-value influence computation to improve the accuracy. Our approach is applicable to most existing truth discovery algorithms. Experiments on real-world datasets show that our approach improves the efficiency compared to existing algorithms while achieving similar or even better accuracy. The scalability is further demonstrated by experiments on large synthetic datasets.Xianzhi Wang, Quan Z. Sheng, Xiu Susie Fang, Xue Li, Xiaofei Xu, and Lina Ya

    Evaluating energy security of resource-poor economies: A modified principle component analysis approach

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    © 2016 Elsevier B.V. This study proposes to aggregately measure energy security performance with the principal component analysis. In its application of the methodology to four resource-poor yet economically advanced island economies in East Asia—Singapore, South Korea, Japan, and Taiwan, this study establishes a novel framework to conceptualize energy security. The framework incorporates three dimensions: vulnerability, efficiency, and sustainability, three indicators being allocated to each dimension. The study finds that all the three dimensions are critical for the resource-poor economies but have different weights in each of them. An urgent task for these four economies is to implement energy efficiency and conservation measures. Liberalization of electricity sector can be a helpful tool to reduce energy consumption and increase efficiency. All of them have been committed to promoting renewable energy development, which shall be further expanded in these economies

    Existence problem of proton semi-bubble structure in the 21+2_1^+ state of 34^{34}Si

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    The fully self-consistent Hartree-Fock (HF) plus random phase approximation (RPA) based on Skyrme-type interaction is used to study the existence problem of proton semi-bubble structure in the 21+2_1^+ state of 34^{34}Si. The experimental excitation energy and the B(E2) strength of the 21+2_1^+ state in 34^{34}Si can be reproduced quite well. The tensor effect is also studied. It is shown that the tensor interaction has a notable impact on the excitation energy of the 21+2_1^+ state and a small effect on the B(E2) value. Besides, its effect on the density distributions in the ground and 21+2_1^+ state of 34^{34}Si is negligible. Our present results with T36 and T44 show that the 21+2_1^+ state of 34^{34}Si is mainly caused by proton transiton from π1d5/2\pi 1d_{5/2} orbit to π2s1/2\pi 2s_{1/2} orbit, and the existence of a proton semi-bubble structure in this state is very unlikely.Comment: 6 pages, 3 figures, 3 table

    Wall-modeled large-eddy simulation integrated with synthetic turbulence generator for multiple-relaxation-time lattice Boltzmann method

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    The synthetic turbulence generator (STG) lies at the interface of the Reynolds averaged Navier-Stokes (RANS) simulation and large-eddy simulation (LES). This paper presents an STG for the multiple-relaxation-time lattice Boltzmann method (LBM) framework at high friction Reynolds numbers, with consideration of near-wall modeling. The Reichardt wall law, in combination with a force-based method, is used to model the near-wall field. The STG wall-modeled LES results are compared with turbulent channel flow simulations at R e τ = 1000 , 2000 , 5200 at different resolutions. The results demonstrate good agreement with direct numerical simulation, with the adaptation length of 6-8 boundary layer thickness. This method has a wide range of potentials for hybrid RANS/LES-LBM related applications at high friction Reynolds numbers

    Influence of an externally modulated photonic link on a microwave communications system

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    We analyze the influence of an externally modulated photonic link on the performance of a microwave communications system. From the analysis, we deduce limitations on the photocurrent, magnitude of the relaxation oscillation noise of the laser, third-order intercept point of the preamplifier, and other parameters in order for the photonic link to function according to the system specifications. Based on this, we outline a procedure for designing a photonic link that can be integrated in a system with minimal performance degradation

    A novel photonic oscillator

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    We report a novel oscillator for photonic RF systems. This oscillator is capable of generating high-frequency signals up to 70 GHz in both electrical and optical domains and is a special voltage-controlled oscillator with an optical output port. It can be used to make a phase-locked loop (PLL) and perform all functions that a PLL is capable of for photonic systems. It can be synchronized to a reference source by means of optical injection locking, electrical injection locking, and PLL. It can also be self-phase locked and self-injection locked to generate a high-stability photonic RF reference. Its applications include high-frequency reference regeneration and distribution, high-gain frequency multiplication, comb-frequecy and square-wave generation, carrier recovery, and clock recovery. We anticipate that such photonic voltage-controlled oscillators (VCOs) will be as important to photonic RF systems as electrical VCOs are to electrical RF systems
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