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To implement cutting-edge services such as highresolution movie streaming and smart metering on mobile networks cost-effectively, mobile operators must meet various conflicting requirements. For example, they must manage a massive number of devices in smart-meter-type machine-to-machine (M2M) applications for which quality-of-service (QoS) requirements are quite lenient. At the same time, they need to support stringent QoS requirements in the form of a few milliseconds of delay and a high bandwidth guarantee for a smaller number of devices in video and remote surgery applications. As building a dedicated per-service physical network is very costly, network slicing by means of resource virtualization was developed to accommodate such heterogeneous services in a single physical network infrastructure. In network slicing, network resources are isolated to form slices, which then can be used to provide different services. This slicing is helpful in accommodating conflicting, often incompatible services at the cost of losing the multiplexing gain achieved in monolithic composite service networks. The loss in multiplexing gain is not a big problem when the number of slices is relatively low. However, numerous services are provided in cellular networks, and the number is expected to be drastically higher in the 5G era. Creating perservice slices would lead to wastage of resources. In this regard, we aim at balancing the need for isolation to meet conflicting service requirements against resource usage efficiency. We investigated possible means of simultaneously achieving isolation and minimizing the loss of multiplexing gain. Our findings will aid in the development of network management architecture suitable for the 5G era and beyond.

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We prepared p-type antimony telluride thin films by an oblique deposition at the incident angle ranging from 0º to 80º. We investigated the relationship between the structural and electrical properties of the thin films. As the structural properties, we analyzed cross-section morphology by scanning electron microscope (SEM), and the crystal orientation and crystallite size by x-ray diffraction (XRD) analysis. As the electrical properties, we measured in-plane electrical conductivity, Seebeck coefficient and power factor at room temperature. As a result, we found the thin film at the incident angle of 40° obtained the highest crystal orientation. As the incident angle increased, the crystallite size were enhanced but the power factor decreased. The power factor of thin film at the incident angle of 0° was 1.26 μW / ( cm·K 2 ) and thin film at the incident angle of 80° was 0.38 μW / ( cm·K 2 ).