Everyone loves a large caching tier in their multitier cloud-based web service because it both alleviates database load and provides lower request latencies. Even when load drops severely, administrators are reluctant to scale down their caching tier. This paper makes the case that (i) scaling down the caching tier is viable with respect to performance, and (ii) the savings are potentially huge...

This paper briefly traces the evolution of information system architectures from mainframe-connected terminals to distributed multi-tier architectures. It presents the challenges facing developers of multi-tier information systems in providing effective consistent data policy enforcement, such as access control in these architectures. Finally, it introduces ‘‘Mobile Policy’’ (MoP) as a potentia...

A replication logic is the set of protocols and mechanisms implementing a software replication technique. A three-tier approach to replication consists in separating the replication logic from both clients and replicated servers by embedding such logic in a middle-tier. In this paper we first introduce the fundamental concepts underlying three-tier replication. This approach has two main practi...

Multi-h CPM has been selected as the Tier II waveform for the Advanced Range Telemetry (ARTM) program, because it offers 50% better spectral efficiency than Feher-patented FQPSK, which is the Tier I waveform. Shaped Offset QPSK has been shown to be nearly identical in performance to Feher-patented FQPSK. Both the Tier I and Tier II waveforms must operate in the presence of adjacent channel inte...

Two-tier cellular networks provide an enhanced use of the networks' resources for both high and low speed users. However, they cause an increase in the number of handoffs between cells due to having smaller cell sizes in the microcell tier. An effective approach used to prevent the dropping of ongoing calls in a network is delaying these calls in a queue until a channel becomes available. In th...

This study described an attempt to develop a networked two-tier test system. A two-tier test is a two-level multiple-choice question that diagnoses students’ alternative conceptions in science. Three networked, two-tier test items were presented in this study. Students in Taiwan (555 14 year olds and 599 16 year olds) were asked to answer these items online. An analysis of students’ answers sug...

introduction: lymphoscintigraphy is imaging of the lymphatic system and has been integrated into the sentinel node mapping procedures. lymphoscintigraphy usually encompasses early or delayed static images. however, immediate dynamic imaging of the lymphatic basins and tumors has also been used as an adjunct lymphoscintigraphy imaging. the aim of this study was to assess the role of early dynami...

In recent years, the population growth rate has been gradually declining in China. As problem becomes increasingly significant, accurate prediction of development trends become a top priority, used to facilitate national scientific planning and effective decision making. Based on historical data spanning period 20 years (1999–2018), this article presents predictions populations 210 prefecture-l...

In this paper, we investigate the coverage performance and energy efficiency of multi-tier heterogeneous cellular networks (HetNets) which are composed of macrocells and different types of small cells, i.e., picocells and femtocells. By virtue of stochastic geometry tools, we model the multi-tier HetNets based on a Poisson point process (PPP) and analyze the Signal to Interference Ratio (SIR) v...