The Resource Mapping Algorithm of Wireless Virtualized Networks for Saving Energy in Ultradense Small Cells

As the current network is designed for peak loads, it results in insufficient resource utilization and energy waste. Virtualized technology makes it possible that intelligent energy perception network could be deployed and resource sharing could become an effective energy saving technology. How to make more small cells into sleeping state for energy saving in ultradense small cell system has become a research hot spot. Based on the mapping feature of virtualized network, a new wireless resource mapping algorithm for saving energy in ultradense small cells has been put forward when wireless resource amount is satisfied in every small cell. First of all, the method divides the virtual cells. Again through the alternate updating between small cell mapping and wireless resource allocation, least amount of small cells is used and other small cells turn into sleeping state on the premise of guaranteeing users’ QoS. Next, the energy consumption of the wireless access system, wireless resource utilization, and the convergence of the proposed algorithm are analyzed in theory. Finally, the simulation results demonstrate that the algorithm can effectively reduce the system energy consumption and required wireless resource amount under the condition of satisfying users’ QoS

The Progress and Trend of Heterogeneous Integration Silicon/III-V Semiconductor Optical Amplifiers

Silicon photonics is a revolutionary technology in the integrated photonics field which has experienced rapid development over the past several decades. High-quality III-V semiconductor components on Si platforms have shown their great potential to realize on-chip light-emitting sources for Si photonics with low-cost and high-density integration. In this review, we will focus on semiconductor optical amplifiers (SOAs), which have received considerable interest in diverse photonic applications. SOAs have demonstrated high performance in various on-chip optical applications through different integration technologies on Si substrates. Moreover, SOAs are also considered as promising candidates for future light sources in the wavelength tunable laser, which is one of the key suitable components in coherent optical devices. Understanding the development and trends of heterogeneous integration Silicon/III-V SOA will help researchers to come up with effective strategies to combat the emerging challenges in this family of devices, progressing towards next-generation applications

A Study of Tapping by the Unaffected Finger of Patients Presenting with Central and Peripheral Nerve Damage

Aim: Whether the unaffected function of the hand of patients presenting with nerve injury is affected remains inconclusive. We aimed to evaluate whether there are differences in finger tapping following central or peripheral nerve injury compared with the unaffected hand and the ipsilateral hand of a healthy subject.Methods: 30 right brain stroke patients with hemiplegia, 30 left arm peripheral nerve injury cases and 60 healthy people were selected. We tested finger tapping of the right hands, and each subject performed the test twice.Results: Finger tapping following peripheral nerve injury as compared with the unaffected hand and the dominant hand of a healthy person was significantly higher than was found for central nerve injury (P<0.05). Finger tapping of the male peripheral group’s unaffected hand and the control group’s dominant hand was significantly higher than the central group (P<0.001). However, finger tapping of the female control group’s dominant hand was markedly higher than the central group’s unaffected hand (P<0.01, P=0.002), the peripheral group’s unaffected hand (P<0.05, P=0.034). Conclusion: The unaffected function of the hand of patients with central and peripheral nerve injury was different as compared with the ipsilateral hand of healthy individuals. The rehabilitation therapist should intensify the practice of normal upper limb fine activities and coordination of the patient

Coumarin Ketoxime Ester with Electron-Donating Substituents as Photoinitiators and Photosensitizers for Photopolymerization upon UV-Vis LED Irradiation

High-performance photoinitiators (PIs) are essential for ultraviolet&ndash;visible (UV-Vis) light emitting diode (LED) photopolymerization. In this study, a series of coumarin ketoxime esters (COXEs) with electron-donating substituents (tert-butyl, methoxy, dimethylamino and methylthio) were synthesized to study the structure/reactivity/efficiency relationships for substituents for the photoinitiation performance of PIs. The introduction of heteroatom electron-donating substituents leads to a redshift in the COXE absorption of more than 60 nm, which matches the UV-Vis LED emission spectra. The PIs also show acceptable thermal stability via differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). The results from real-time Fourier transform infrared (RT-FTIR) measurements indicate that COXEs show an excellent photoinitiation efficiency for free radical polymerization under UV-Vis LED irradiation (365&ndash;450 nm); in particular, the conversion efficiency for tri-(propylene glycol) diacrylate (TPGDA) polymerization initiated by COXE-O and COXE-S (4.8 &times; 10&minus;5 mol&middot;g&minus;1) in 3 s can reach more than 85% under UV-LED irradiation (365, 385 nm). Moreover, the photosensitization of COXEs in the iodonium hexafluorophosphate (Iod-PF6) and hexaarylbiimidazole/N-phenylglycine (BCIM/NPG) systems was investigated via RT-FTIR. As a coinitiator, COXEs show excellent performance in dry film photoresist (DFR) photolithography. This excellent performance of COXEs demonstrates great potential for UV-curing and photoresist applications, providing a new idea for the design of PIs

A General Synthetic Strategy for the Synthesis of Imine-Linked Covalent Organic Frameworks in Choline Chloride–Hexafluoroisopropanol-Based Deep Eutectic Solvents

The imine-linked covalent organic frameworks (COFs) have garnered significant attention in various fields due to exceptional stability and polyamide structures, etc. However, the conventional synthetic protocols for the high-crystallinity imine-linked COFs often necessitate the use of harmful organic solvent and extra catalyst, rendering their synthesis environmentally detrimental. Therefore, it is imperative to develop facile methods for COF preparation that employ green solvents without the need of extra catalyst. Herein, an environmentally friendly, efficient, general synthetic strategy was developed to synthesize five imine-linked COFs with high yield and high crystallinity by using choline chloride (ChCl)–hexafluoro­isopropanol (HFIP) linked deep eutectic solvents (DESs) as general solvents for the first time. Unlike other reactions that required repeated exploration of the types of solvents to synthesize COFs with high crystallinity, the as-developed method only required changing the molar ratio of ChCl and HFIP in DES; various imine-linked COFs with high crystallinity can be synthesized. To further elucidate the formation of imine-linked COFs in ChCl-HFIP-based DESs, COF-CH-1, which was prepared using 1,3,5-tris(4-amino­phenyl)benzene (TPB) and terephthalaldehyde (TPDD) as precursors, was regarded as an example. The formation process of COF-CH-1 was preliminarily deduced linked on the changes of morphology, functional groups, element compositions, etc., with the change of reaction temperature and reaction time in optimal DES. Finally, according to the results, we also preliminarily speculated on the possible role of DESs in COFs’ formation