Context-awareness for mobile sensing: a survey and future directions

The evolution of smartphones together with increasing computational power have empowered developers to create innovative context-aware applications for recognizing user related social and cognitive activities in any situation and at any location. The existence and awareness of the context provides the capability of being conscious of physical environments or situations around mobile device users. This allows network services to respond proactively and intelligently based on such awareness. The key idea behind context-aware applications is to encourage users to collect, analyze and share local sensory knowledge in the purpose for a large scale community use by creating a smart network. The desired network is capable of making autonomous logical decisions to actuate environmental objects, and also assist individuals. However, many open challenges remain, which are mostly arisen due to the middleware services provided in mobile devices have limited resources in terms of power, memory and bandwidth. Thus, it becomes critically important to study how the drawbacks can be elaborated and resolved, and at the same time better understand the opportunities for the research community to contribute to the context-awareness. To this end, this paper surveys the literature over the period of 1991-2014 from the emerging concepts to applications of context-awareness in mobile platforms by providing up-to-date research and future research directions. Moreover, it points out the challenges faced in this regard and enlighten them by proposing possible solutions

Assessing the Impact of EEE Standard on Energy Consumed by Commercial Grade Network Switches

This book chapter is adapted from [1] and it is closely linked to work published in [2] and [3]. Reducing power consumption of network equipment has been both driven by a need to reduce the ecological footprint of the cloud as well as the im-mense power costs of data centers. As data centers, core networks and conse-quently, the cloud, constantly increase in size, their power consumption should be mitigated. Ethernet, the most widely used access network still remains the biggest communication technology used in core networks and cloud infrastructures. The Energy-Efficient Ethernet or EEE standard introduced by IEEE in 2010, aims to reduce the power consumption of EEE ports by transitioning Ethernet ports into a low power mode when traffic is not present. As statistics show that the average utilization rate of ethernet links is 5 percent on desktops and 30 percent in data centers, the power saving potential of EEE could be immense. This research aims to assess the benefits of deploying EEE and create a power consumption model for network switches with and without EEE. Our measurements show that an EEE port runs at 12-15% of its total power when in low power mode. Therefore, the power savings can exceed 80% when there is no traffic. However, our measure-ments equally show that the power consumption of a single port represents less than 1% of the total power consumption of the switch. The base power consumed by the switch without any port is still significantly high and is not affected by EEE. Experiment results also show that the base power consumption of switches does not significantly increase with the size of the switches. Doubling the size of the switch between 24 and 48 ports increases power consumption by 35.39%. EEE has a greater effect on bigger switches, with a power (or energy) gain on the EEE-enabled 48-port switch compared to 2 x EEE-enabled 24-port switch. On the other hand, it seems to be more energy efficient to use 2 separate 24-port switches (NO EEE) than 2 separate 24-port switches (With EEE)

FRESENIUS ENVIRONMENTAL BULLETIN

To document and understand dinoflagellate cyst assemblages, 6 surface sediment samples were collected from Iskenderun Bay, in the northeastern Mediterranean. A total of 28 cyst types were identified and the cyst concentration was attained as 144 cysts g-' dry weight sediment in the bay. The cyst concentration was low when compared to other areas in the Mediterranean. Lingulodinium machaerophorum, SpiMferites bulloideus, and Brigantedinium spp. were the most abundant cysts in the sampling points. Three of the stations had a sandy sediment grain size, while the other stations had a muddy (silt + clay) sediment distribution. Only the clay exhibited a significantly strong positive correlation with the total and heterotrophic dinoflagellate cyst concentrations, whereas no other strong correlation was found between the sediment grain size and dinoflagellate cysts. The present study provides the first modern dinoflagellate cyst records from the surface sediments of Iskenderun Bay, in the northeastern Mediterranean

Energy Efficient Context-Aware Framework in Mobile Sensing

The ever-increasing technological advances in embedded systems engineering, together with the proliferation of small-size sensor design and deployment, have enabled mobile devices (e.g., smartphones) to recognize daily occurring human based actions, activities and interactions. Therefore, inferring a vast variety of mobile device user based activities from a very diverse context obtained by a series of sensory observations has drawn much interest in the research area of ubiquitous sensing. The existence and awareness of the context provides the capability of being conscious of physical environments or situations around mobile device users, and this allows network services to respond proactively and intelligently based on such awareness. Hence, with the evolution of smartphones, software developers are empowered to create context aware applications for recognizing human-centric or community based innovative social and cognitive activities in any situation and from anywhere. This leads to the exciting vision of forming a society of ``Internet of Things which facilitates applications to encourage users to collect, analyze and share local sensory knowledge in the purpose for a large scale community use by creating a smart network which is capable of making autonomous logical decisions to actuate environmental objects. More significantly, it is believed that introducing the intelligence and situational awareness into recognition process of human-centric event patterns could give a better understanding of human behaviors, and it also could give a chance for proactively assisting individuals in order to enhance the quality of lives. Mobile devices supporting emerging computationally pervasive applications will constitute a significant part of future mobile technologies by providing highly proactive services requiring continuous monitoring of user related contexts. However, the middleware services provided in mobile devices have limited resources in terms of power, memory and bandwidth as compared to the capabilities of PCs and servers. Above all, power concerns are major restrictions standing up to implementation of context-aware applications. These requirements unfortunately shorten device battery lifetimes due to high energy consumption caused by both sensor and processor operations. Specifically, continuously capturing user context through sensors imposes heavy workloads in hardware and computations, and hence drains the battery power rapidly. Therefore, mobile device batteries do not last a long time while operating sensor(s) constantly. In addition to that, the growing deployment of sensor technologies in mobile devices and innumerable software applications utilizing sensors have led to the creation of a layered system architecture (i.e., context aware middleware) so that the desired architecture can not only offer a wide range of user-specific services, but also respond effectively towards diversity in sensor utilization, large sensory data acquisitions, ever-increasing application requirements, pervasive context processing software libraries, mobile device based constraints and so on. Due to the ubiquity of these computing devices in a dynamic environment where the sensor network topologies actively change, it yields applications to behave opportunistically and adaptively without a priori assumptions in response to the availability of diverse resources in the physical world as well as in response to scalability, modularity, extensibility and interoperability among heterogeneous physical hardware. In this sense, this dissertation aims at proposing novel solutions to enhance the existing tradeoffs in mobile sensing between accuracy and power consumption while context is being inferred under the intrinsic constraints of mobile devices and around the emerging concepts in context-aware middleware framework

Generic and energy-efficient context-aware mobile sensing

This book proposes novel context-inferring algorithms and generic framework designs to enhance the existing tradeoffs in mobile sensing, especially between accuracy and power consumption. It integrates the significant topics of energy efficient, inhomogeneous, adaptive, optimal context-aware inferring algorithm and framework design. In addition, it includes plenty of examples to help readers understand the theory, best practices, and strategies

Medical Use of Sensor-Based Devices, the Debates Around and Implementation in Education

Sensor-based diagnostics are increasing rapidly and in clinics, they can transform the health care as they will be in use out of clinics as well, namely, by the non-clinicians and people without expertise. The trade-off between the advantages and disadvantages of their implementation into the clinical settings should be decisive in their use, at the current state. Yet, disadvantages must be carefully worked out and tried to be eliminated in any case, while keeping the inborn benefits. Therefore, we would like to draw attention to the reliability and security risks of personal health data and associated concerns. We further discuss the related issues of sensor-based diagnostics, mobile health (mHealth) and eHealth. The debate starts with the current states of the rules and regulations. It is argued that there is prompt need for internationally consolidated solutions for vast device types and uses onto which the local needs may have to be implemented without violating the basic assets such as the inherent privacy rights of the users/patients. The resistance factors against the sensor-based healthcare devices and applications are also conferred. There are additionally data quality and assessment issues, and in relation to the data assessment, concerns that are associated with the psychological responses of the layman to the health data are mentioned. For these and more reasons, and finally for proper use and implementation of sensor-based tests and devices in the clinical settings, education of both professionals and non-professionals seems to be the key. All these require much work and maybe even more workforces to be allocated for the emerging, associated tasks. However, there are economic benefits, and beyond those, they bring new features in the health care that were deemed to be impossible. Besides, despite the apparent unethical use risks, they can result in better ethical practices, e.g., possible prevention of unnecessary tests on animals when similar test on organ-on-chips would be failing

Factors Influencing Intercultural Sensitivity of Hospitality Employees

This study investigates the factors influencing the development of intercultural sensitivity among hospitality employees. The study particularly looks at the relationship between intercultural sensitivity levels of hospitality employees and their previous educational work experiences. Based on a survey (Intercultural Sensitivity Scale) scale with 443 hospitality employees overall means were calculated. Results of the analysis show that exposure to other cultures by participating previously in student exchange programs (e.g. ERASMUS), work and travel programs, and spending long periods of time abroad increased people’s intercultural sensitivity. Interestingly though, the study found that having formal tourism and hospitality education did not have any influence on the level of intercultural sensitivity of hospitality employees. © 2018, © 2018 Taylor & Francis

Modeling Battery Behavior on Sensory Operations for Context-Aware Smartphone Sensing

Energy consumption is a major concern in context-aware smartphone sensing. This paper first studies mobile device-based battery modeling, which adopts the kinetic battery model (KiBaM), under the scope of battery non-linearities with respect to variant loads. Second, this paper models the energy consumption behavior of accelerometers analytically and then provides extensive simulation results and a smartphone application to examine the proposed sensor model. Third, a Markov reward process is integrated to create energy consumption profiles, linking with sensory operations and their effects on battery non-linearity. Energy consumption profiles consist of different pairs of duty cycles and sampling frequencies during sensory operations. Furthermore, the total energy cost by each profile is represented by an accumulated reward in this process. Finally, three different methods are proposed on the evolution of the reward process, to present the linkage between different usage patterns on the accelerometer sensor through a smartphone application and the battery behavior. By doing this, this paper aims at achieving a fine efficiency in power consumption caused by sensory operations, while maintaining the accuracy of smartphone applications based on sensor usages. More importantly, this study intends that modeling the battery non-linearities together with investigating the effects of different usage patterns in sensory operations in terms of the power consumption and the battery discharge may lead to discovering optimal energy reduction strategies to extend the battery lifetime and help a continual improvement in context-aware mobile services