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Content delivery service has become a major traffic load on today's Internet, and this has triggered the interest of ISPs in operating their own content delivery networks (CDNs) to optimize Internet traffic considering both content delivery caching and user-network proximity. ISPs, however, are typically regionally bound or network-domain-wise isolated; hence, their CDN gain is somewhat limited. In order to enhance the gain of ISP CDN services to the level of incumbent global CDNs, a CDN interconnection (CDNI) model is introduced by IETF, where local ISP CDN services can be extended among heterogeneous CDNs across network domains. However, despite the multiple benefits of a CDNI system, it is difficult to apply a CDNI service to the current CDN market due to the platform independence. Hence, we introduced a CDNI gateway model that is standard-capable and platform-independent. With the CDNI gateway model, we design and implement a complete CDNI system and conduct a CDNI service trial with three major ISPs in South Korea. To the best of our knowledge, this is the first CDNI service trial complying with the IETF standard achieved by a multi-ISP collaboration. According to the analysis of experimental results from the service trial, we observe that CDNI can reduce content traffic by about 40 percent at the Internet exchange link compared to a legacy CDN system.

This paper reports that SnO additive in an alkaline solution can effectively suppress the dendritic growth of electrolytic Zn. There was a remarkable change in the voltammetric behavior with increasing SnO additive content, which indicated its strong effect on the redox reaction of Zn. A higher additive content resulted in greater suppression of the dendritic growth of electrolytic Zn. From the compositional analysis of the electrodeposit, it was confirmed that Sn was co-deposited with Zn in amounts up to around 1 at.%. This implied that the incorporated Sn hindered the typical dendritic growth of electrolytic Zn. However, excess SnO resulted in rough and crumbling electrodeposits because of the formation of relatively large amount of a pure Sn phase.

In this work, the effect of ZnO precipitation on the electrochemical cycling stability of Zn–air batteries was systematically investigated. The results suggest that sustained electrical rechargeability can be achieved by simply appropriately choosing the amount of Zn metal anode, such that the amount of zincate ions released into the electrolyte upon full discharge of the anode is below the supersaturated solubility limit. For example, there was almost no capacity fading up to 50 cycles when the anode was designed such that the amount of zincate ions released into the electrolyte was a bit less than the chemical solubility limit of ZnO in KOH solution. Despite its limited energy density, the results presented in this study provide an important direction to the future work on electrically rechargeable Zn–air batteries.

Coptidis Rhizoma is derived from the dried rhizome of Ranunculaceous plants and is a commonly used traditional Chinese medicine. Although Coptidis Rhizoma is commonly used for its many therapeutic effects, antiviral activity against respiratory syncytial virus (RSV) has not been reported in detail. In this study, we evaluated the antiviral activities of Coptidis Rhizoma extract (CRE) against RSV in human respiratory tract cell line (HEp2) and BALB/c mice. An effective dose of CRE significantly reduces the replication of RSV in HEp2 cells and reduces the RSV-induced cell death. This antiviral activity against RSV was through the induction of type I interferon-related signaling and the antiviral state in HEp2 cells. More importantly, oral administration of CRE exhibited prophylactic effects in BALB/c mice against RSV. In HPLC analysis, we found the presence of several compounds in the aqueous fraction and among them; we confirmed that palmatine was related to the antiviral properties and immunemodulation effect. Taken together, an extract of Coptidis Rhizoma and its components play roles as immunomodulators and could be a potential source as promising natural antivirals that can confer protection to RSV. These outcomes should encourage further allied studies in other natural products.

Aligned carbon nanotubes (CNTs) were grown on an aluminum foil laminated on a flexible stainless steel (SS) substrate. Lamination was carried out under a pressure of 10 MPa with simultaneously heating at 400 °C. The laminated Al foil was spray-coated with an iron chloride catalyst precursor solution and the CNTs were grown using water-assisted chemical vapor deposition at 810 °C. The CNTs grew as vertically aligned forests, approximately 600 μm in height, within 600 s without crumpling of the Al foil. The Al foil acts as a sacrificial barrier layer to grow the CNTs. The CNTs had 2–30 walls with an inner diameter of 3–8 nm. Thermogravimetric and field emission analysis of the CNTs revealed a degradation temperature and turn-on field of 643.5 °C and 0.46 V/μm, respectively. Transmission electron microscopy and X-ray photoelectron spectroscopy were used to analyze the Al–SS interface and chemical states. After removing the CNTs, the flexible SS substrate could be cleaned, recoated with Al and reused for CNT growth. Overall, this process is a repeatable and continuous roll-to-roll processable method that can be scaled up for industrial production.

In providing video-on-demand (VoD) services to a number of clients through networks, the bandwidth requirements of video transmission restrict VoD services. For this reason, many significant broadcasting-based VoD schemes have been proposed to efficiently support services. However, the broadcasting-based VoD schemes approach needs frequency channel hopping, using many channels at the same time and managing many segments of a video. These make it difficult to implement. In this paper, we propose a harmonic staggered broadcasting scheme which has a simple structure and substantially improved VoD efficiency. The proposed scheme substantially reduces the number of segments required and the frequency for switching channels. Also this new scheme performs significantly better than the existing VoD schemes in viewer's waiting time and buffer requirements with simplicity. The numerical results demonstrate that the viewer's waiting time of the harmonic staggered broadcasting scheme is close to the harmonic broadcasting scheme and the buffer requirements of this can be adjusted by a video dividing coefficient h .