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The practical Kramers-Kronig (KK) receiver has been a competitive receiving technique in the data-center, medium reach, and even long-haul metropolitan networks. Nevertheless, an extra digital resampling operation is required at both ends of the KK field reconstruction algorithm due to the spectrum broadening caused by adopting the nonlinear function. Generally, the digital resampling function can be implemented by using linear interpolation (LI-ITP), the Lagrange cubic interpolation (LC-ITP), the spline cubic interpolation (SC-ITP), time-domain anti-aliasing finite impulse response (FIR) filter method (TD-FRM) scheme, and fast Fourier transform (FFT)-based scheme. However, the performance and the computational complexity analysis of different resampling interpolation schemes in the KK receiver have not been thoroughly investigated yet. Different from the interpolation schemes of conventional coherent detection, the interpolation function of the KK system is followed by the nonlinear operation, which will broaden the spectrum significantly. Due to the frequency-domain transfer function of different interpolation schemes, the broadened spectrum will have a potential spectrum aliasing, which will cause serious inter-symbol interference (ISI) and further impair the KK phase retrieval performance. We experimentally investigate the performance of different interpolation schemes under different digital up-sampling rates (i.e. the computational complexity) as well as the cut-off frequency, the tap number of the anti-aliasing filter, and the shape factor of the TD-FRM scheme in a 112-Gbit/s SSB DD 16-QAM system over 1920-km Raman amplification (RFA)-based standard single-mode fiber (SSMF). The experimental results involve that the TD-FRM scheme outperforms other interpolation schemes and the complexity is reduced by at least 49.6%. In fiber transmission results, take 20% soft decision-forward error correction (SD-FEC) of 2×10−2 as the threshold, the LI-ITP and LC-ITP schemes only reach 720-km while others can reach up to 1440-km.

A transition-metal-free, facile and efficient method for the synthesis of 3-alkynylpyrrole-2,4-dicarboxylates from methylene isocyanides and propiolaldehyde with moderate to good yields has been developed. The direct transformation process and good tolerance of various substituents make it an alternative approach to previous protocols, and potential applications of these investigated compounds are expected with or without post-modifications.

We report the first demonstration of the use of probabilistic-shaping-programmable real-time 200-Gb/s coherent transceivers in a deploying intelligent core network to achieve improved performance, energy-efficiency, and protection in case of fiber cuts, showing the benefits of such probabilistic-shaping-programmable transceivers.

A kind of far infrared radiation ceramics was prepared by using iron ore tailings, CaCO3 and SiO2 as main raw materials, and Ce as additive. The result of Fourier transform infrared spectroscopy showed that the sample exhibits excellent radiation value of 0.914 when doping 7 wt.% Ce. Ce4+ dissolved into iron diopside and formed interstitial solid solution with it sintered at 1150 °C. The oxidation of Fe2+ to Fe3+ caused by Ce4+ led to a decrease of crystallite sizes and enhancement of Mg–O and Fe–O vibration in iron diopside, which consequently improved the far infrared radiation properties of iron ore tailings ceramics.

A kind of far infrared radiation ceramics was prepared by using silicate minerals, calcium carbonate and silicon dioxide as main raw materials, and cerium nitrate as additive. The structure of the ceramics and far infrared radiation properties on the surface tension of water were characterized by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and a tensiometer, respectively. It was showed that, after being sintered at 1160 °C, the solid solution was formed by CeO2 and Fe2O3, thus the crystal parameters (c/a axis ratio) and interplanar spacing of Fe2O3 increased. The addition of cerium was regarded to improve the far infrared radiation of ceramics, and the maximum emissivity value in the range of 5–20 μm was 0.94. The surface tension of water gradually decreased with increasing radiation time.

Fronthaul using CPRI between BBU and RRU equipments is carried by bare fiber currently. As BBUs are more and more centralized as a pool, tremendous amount of connections may exhaust the dark fiber resource. Various optical solutions are proposed to carry CPRI. As CPRI brings stringent physical requirements, optical transmission and access technologies need to be optimized and modified. In this paper, different optical solutions for fronthaul including OTN, passive WDM, active WDM and WDM-PON are analyzed and compared. Moreover, trials using these technologies to carry CPRI are conducted in commercial LTE environment. No worse physical performance is shown for optical solutions with more powerful OAM functions.

Although the risk of neurological cancer (NC) is age-dependent, few studies have evaluated the prognostic value of age in determining NC survival in a large population. The aim of this retrospective study was to compare the long-term survival of young and elderly NC patients. We searched the Surveillance, Epidemiology, and End-Results database and identified 22,393 patients who were diagnosed with NC between 1988 and 2003 and were treated with surgery. Patients were categorized as young (≤40 years old) or elderly (>40 years old), and 5-year NC-specific survival (NCSS) data were obtained for each patient. A Kaplan-Meier survival analysis and the Cox proportional hazards model were used to analyze long-term survival outcomes and risk factors. The two groups differed significantly in terms of pathological grade, histological type, stage, and tumor size (P

We demonstrate a control mechanism for multi-domain optical networks with commercial OTN equipments by using hierarchical SDN controllers. A solution based on extended OpenFlow was proposed to support Control Virtual Network Interface in OTN network.

In this paper, routing and wavelength assignment (RWA) algorithms whose optimum object is the minimum number of wavelength required in wavelength division multiplexing all optical network were studied. Since the number of wavelength required (NWR) obtained by the existing two RWA algorithms is associated with the numbering order of the nodes in the network, a statistics method was proposed to modify the RWA algorithms. With this statistics method, a smaller NWR can be acquired. And, it is the first time that the statistics method was proposed to compare the performance of different RWA algorithms. Two RWA algorithms can be compared by contrasting the distribution of the NWRs obtained by each RWA algorithms.

Since reform and opening-up, China has eliminated many regulations which limited the free migration of population, and the market economic impact on migration became increasingly strong, population migration becomes a common social phenomenon. In order to research temporal and spatial variations of Chinese population migration characteristics from sampling survey data in recent 10 years, we apply Moran's I & Geary's C to explore the spatial effects of migration's spatial distribution pattern. It turns out — the main immigration regions gradually expanded from the Pearl River Delta area to the Yangtze River Delta and Bohai Rim region in late decade, and showing a multi-polar pattern. Meanwhile, the population outmigration regions showed a spatial convergence trend from northwest and northeast to the central region. Then, we analyze the influence factors of population migration with grey associated entropy, and find that regional economic development level, urbanization level & region openness degree all have a positive stimulus on the immigration.

A control mechanism for multi-domain optical networks with commercial optical transport network (OTN) equipment is demonstrated by using hierarchical software defined networking controllers. A solution based on extended OpenFlow is proposed to support the control virtual network interface in OTN networks. In this way, multi-vendor and multi-domain interoperability is achieved for transport networks, and bandwidth on demand (BoD) service is demonstrated in multi-vendor multi-domain OTN networks. Moreover, based on this hierarchical control architecture, BoD service is conducted in the field trial, which verifies the feasibility to introduce new services in the transport network.

In this paper, routing and wavelength assignment (RWA) algorithms whose optimum object is the minimum number of wavelength required (MNWR) in WDM All Optical Network were studied. Since the number of wavelength required (NWR) obtained by the existing two RWA algorithms is associated with the numbering order of the nodes in the network, a statistical method was proposed to modify the RWA algorithms. With statistical method, a smaller NWR can be acquired. And, it is the first time that the statistical method was proposed to compare the RWA algorithms. Two RWA algorithms can be compared by contrasting the distribution of the NWRs obtained by each RWA algorithm.