On Max-SINR Receiver for Hexagonal Multicarrier Transmission Over Doubly Dispersive Channel

In this paper, a novel receiver for Hexagonal Multicarrier Transmission (HMT) system based on the maximizing Signal-to-Interference-plus-Noise Ratio (Max-SINR) criterion is proposed. Theoretical analysis shows that the prototype pulse of the proposed Max-SINR receiver should adapt to the root mean square (RMS) delay spread of the doubly dispersive (DD) channel with exponential power delay profile and U-shape Doppler spectrum. Simulation results show that the proposed Max-SINR receiver outperforms traditional projection scheme and obtains an approximation to the theoretical upper bound SINR performance within the full range of channel spread factor. Meanwhile, the SINR performance of the proposed prototype pulse is robust to the estimation error between the estimated value and the real value of time delay spread.Comment: 6 pages. The paper has been published in Proc. IEEE GLOBECOM 2012. Copyright transferred to IEEE. arXiv admin note: text overlap with arXiv:1212.579

Sino-Poland intercollegiate cooperation in tertiary education: The case study of “Nicolaus Copernicus University 3 + 1 + 2 intercollegiate cooperation” project

Purpose: This paper aims to identify the strengths and challenges of Sino-Poland intercollegiate cooperation in tertiary education projects and give recommendations for such cross-culture cooperation projects.Methodology/approach: This paper utilized qualitative study analysis that conducted and interpreted semi-structured in-depth individual interviews with Chinese students participating in "Nicolaus Copernicus University 3 + 1 + 2 intercollegiate cooperation" project. Data is coded and analyzed using sentiment analysis.Findings: The study shows that Sino-Poland intercollegiate cooperation is gradually developing, which has apparent strengths, including increased the number of Chinese students, promotion of Sino-Poland university cooperation, and creation of distinctive cooperation models. However, some of the challenges that have emerged include project overly seeking profit-oriented, the declining admission standards, and cultural differences in Sino-Poland tertiary education cooperation and competition from universities in other European countries.Implications: The results of the study give practical suggestions for Sino-Poland intercollegiate cooperation. As Sino-Poland intercollegiate cooperation is still in its infancy, Chinese and Poland universities should innovate their cooperation models in a cross-cultural context, enhance their communication, and publicize their projects extensively to promote mutual benefits. Simultaneously, the cooperation projects should not be profit-driven and lower the admissions standards because the cooperation projects' reputation is also crucial.Originality/value: The study contributes to the theory development on cross-cultural cooperation between Sino-Poland tertiary education, in particular, it offers insights into the challenges that arise in Sino-Poland intercollegiate cooperation projects and how to develop better cooperation models in the future so that Sino-Poland tertiary education cooperation can develop its own unique symbiotic culture and management model.Keywords: Sino-Poland, cross-culture cooperation, tertiary education, intercollegiate cooperationPaper type: Case stud

Coproduction of liquids and syngas via residue oil cracking-coke gasification (RCCG) process

Due to the extinction of conventional oil resources, large portions of heavy oil will be exploited and processed in the refinery, thus in-return generating more degraded residue oil. Fluid catalytic cracking (FCC) process is unable to treat such kind of residue oil because of rapid catalyst deactivation and excessive coke deposition. Delayed coking, featured with wide feed adaptation and low investment, has been widely used for treating petroleum residues in China. Nonetheless, delayed coking has low liquid yield and produces low-value petroleum coke. As a result, a so-called residue cracking–coke gasification (RCCG) process was proposed to realize the hierarchical conversion and value-added utilization of petroleum residues. Heavy oil was first cracked in a fluidized bed reactor via contacting with the catalyst particles to maximize the liquid yield. Coke deposited on the surface of catalysts was gasified and/or combusted for catalyst regeneration. Simultaneously, high-quality syngas could be produced via coke gasification and further used as the hydrogen source for liquid oil upgrading. The regenerated hot catalysts circulated back to the cracking reactor, providing heat and also catalytic activity for heavy oil conversion. Cracking behaviors of Venezuela vacuum residue were studied in a self-designed fluidized bed reactor (Fig. 1) with spent FCC catalyst to optimize operation parameters for high liquid yield and conversion of heavy fractions. The results showed that the hydrothermal-treated FCC catalyst (A-FCC) showed reasonable activity for residue oil cracking to ensure the acceptable liquid yield and low coke formation. The residue oil conversion above 90% and liquid yield over 75 wt.% were obtained under the operation conditions of 520℃, catalyst-to-oil mass ratio of 6.17 and steam-to-oil mass ratio of 0.6 using A-FCC catalyst. Two methods of catalyst regeneration were used in batch operation, i.e., steam gasification and gasification coupled with combustion of the deposited coke on the catalyst. Steam gasification of the deposited coke was performed at 800℃ for the catalyst regeneration, and the total volume fraction of CO and H2 was up to 86 vol.%. In comparison with coke gasification, catalyst regeneration via gasification-combustion was shown to be able to shorten the required reaction time by about 40% (see Fig. 2), while the regenerated A-FCC catalyst manifested the catalytic activity similar to that of the original A-FCC catalyst. RCCG process is characterized with higher liquid yield and lower coke production than that of delayed coking, and also could process heavy feed oil and produce syngas comparing with FCC process, thus justified its technology advantages. Please click Additional Files below to see the full abstract

A concurrent design approach and model management support to prevent inconsistencies in multidisciplinary modelling and simulation

Cyber-physical systems are multidisciplinary systems which involve different engineering disciplines in their design. Each engineering discipline tends to use its own domain-specific languages and tools to model different aspects of a system concurrently. The concurrent modelling process may introduce inconsistencies due to lack of common knowledge and communication among domain experts. Especially for co-modelling and co-simulation developments, a huge amount of models, versions of models and design alternatives may be produced, which highly increases the design space and the chance of having inconsistent models. This paper introduces a model management support and concurrent design flow to prevent inconsistencies and maintain synchronization among models. Besides the consistency checking scheme, a co-evolution graph can be generated by the model management system to visualize the concurrent development process and prevent inconsistencies. The model management system and concurrent design flow have been applied on a line following robot to show how to use this approach and its advantages

Clearing residual planetesimals by sweeping secular resonances in transitional disks: a lone-planet scenario for the wide gaps in debris disks around Vega and Fomalhaut

Extended gaps in the debris disks of both Vega and Fomalhaut have been observed. These structures have been attributed to tidal perturbations by multiple super-Jupiter gas giant planets. Within the current observational limits, however, no such massive planets have been detected. Here we propose a less stringent `lone-planet' scenario to account for the observed structure with a single eccentric gas giant and suggest that clearing of these wide gaps is induced by its sweeping secular resonance. During the depletion of the disk gas, the planet's secular resonance propagates inward and clears a wide gap over an extended region of the disk. Although some residual intermediate-size planetesimals may remain in the gap, their surface density is too low to either produce super-Earths or lead to sufficiently frequent disruptive collisions to generate any observable dusty signatures. The main advantage of this lone-planet sweeping-secular-resonance model over the previous multiple gas giant tidal truncation scenario is the relaxed requirement on the number of gas giants. The observationally inferred upper mass limit can also be satisfied provided the hypothetical planet has a significant eccentricity. A significant fraction of solar or more massive stars bear gas giant planets with significant eccentricities. If these planets acquired their present-day kinematic properties prior to the depletion of their natal disks, their sweeping secular resonance would effectively impede the retention of neighboring planets and planetesimals over a wide range of orbital semi-major axes.Comment: 20 pages, 12 figures. Accepted for publication in Ap