A Pan-Function Model for the Utilization of Bandwidth Improvement and PAPR Reduction

Aiming at the digital quadrature modulation system, a mathematical Pan-function model of the optimized baseband symbol signals with a symbol length of 4T was established in accordance with the minimum out-band energy radiation criterion. The intersymbol interference (ISI), symbol-correlated characteristics, and attenuation factor were introduced to establish the mathematical Pan-function model. The Pan-function was added to the constraints of boundary conditions, energy of a single baseband symbol signal, and constant-envelope conditions. Baseband symbol signals with the optimum efficient spectrum were obtained by introducing Fourier series and minimizing the Pan-function. The characteristics of the spectrum and peak-to-average power ratio (PAPR) of the obtained signals were analyzed and compared with the minimum shift keying (MSK) and quadrature phase-shift keying (QPSK) signals. The obtained signals have the characteristics of a higher spectral roll-off rate, less out-band radiation, and quasi-constant envelope. We simulated the performance of the obtained signals, and the simulation results demonstrate that the method is feasible

An incremental points-to analysis with CFL-reachability

Abstract. Developing scalable and precise points-to analyses is increasingly important for analysing and optimising object-oriented programs where pointers are used pervasively. An incremental analysis for a program updates the existing analysis information after program changes to avoid reanalysing it from scratch. This can be efficiently deployed in software development environments where code changes are often small and frequent. This paper presents an incremental approach for demand-driven context-sensitive points-to analyses based on Context-Free Language (CFL) reachability. By tracing the CFL-reachable paths traversed in computing points-to sets, we can precisely identify and recompute on demand only the points-to sets affected by the program changes made. Combined with a flexible policy for controlling the granularity of traces, our analysis achieves significant speedups with little space overhead over reanalysis from scratch when evaluated with a null dereferencing client using 14 Java benchmarks.

Buckwheat: a crop from outside the major Chinese domestication centres? A review of the archaeobotanical, palynological and genetic evidence.

The two cultivated species of buckwheat, Fagopyrum esculentum (common buckwheat) and F. tataricum (Tartary buckwheat) are Chinese domesticates whose origins are usually thought to lie in upland southwestern China, outside the major centres of agricultural origins associated with rice and millet. Synthesis of the macro- and microfossil evidence for buckwheat cultivation in China found just 26 records across all time periods, of which the majority were pollen finds. There are few or no identifying criteria distinguishing F. esculentum and F. tataricum for any sample type. The earliest plausibly agricultural Fagopyrum occurs in northern China from the mid 6th millennium cal bp. The archaeobotanical record requires reconciliation with biogeographic and genetic inferences of a southwestern Chinese origin for buckwheat. Scrutiny of the genetic data indicates limitations related to sampling, molecular markers and analytical approaches. Common buckwheat may have been domesticated at the range margins of its wild progenitor before its cultivation expanded in the north, mediated by changing ranges of wild species during the Holocene and/or by cultural exchange or movement of early agriculturalists between southwest China, the Chengdu Plain and the southern Loess Plateau. Buckwheat probably became a pan-Eurasian crop by the 3rd millennium cal bp, with the pattern of finds suggesting a route of westward expansion via the southern Himalaya to the Caucasus and Europe.MKJ and HVH were supported by a European Research Council Advanced Investigator award to MKJ (GA249642, ‘Food Globalization in Prehistory)’. HVH was supported by a University of Cambridge Returning Carers’ Scheme award. SX was supported by grants from the National Natural Science Foundation of China (41471167), and National Scholarship Fund of China (CSC no. 201504910101)

A Conceptual Framework for Smart City International Standards

Smart cities construction has been a global focus during the past ten years. It contributes to the achievement of the sustainability development goals (for economy, society, and environment) by leveraging information and communication technologies (ICTs). International organizations (such as ISO, IEC, and ITU-T) have developed standards to encapsulate precise and state-of-the-art knowledge regarding research, practice and policy. However, thousands of such standards have not been fully used due to the lack of generally agreed vocabularies or frameworks. In this article, a conceptual framework named ‘ALL’ is proposed. Some initial evaluations on the proposed framework have been performed. The result shows that the framework could help people observe, organize and use such standards more efficiently. Some preliminary conversations with governments prove the potential usefulness of the framework in practice