http://www.eecs.ucf.edu/~dcm/Teaching/COT4810-Spring2011/Literature/SensorNetworksSurvey.pdf

Wireless sensor networks: a survey

The advancement in wireless communications and electronics has enabled the development of low-cost sensor networks. The sensor networks can be used for various application areas (e.g., health, military, home). For different application areas, there are different technical issues that researchers are currently resolving. The current state of the art of sensor networks is captured in this article, where solutions are discussed under their related protocol stack layer sections. This article also points out the open research issues and intends to spark new interests and developments in this field.

/pdf/a-survey-on-sensor-networks-5beav0ez6k.pdf

A survey on sensor networks

Networking together hundreds or thousands of cheap microsensor nodes allows users to accurately monitor a remote environment by intelligently combining the data from the individual nodes. These networks require robust wireless communication protocols that are energy efficient and provide low latency. We develop and analyze low-energy adaptive clustering hierarchy (LEACH), a protocol architecture for microsensor networks that combines the ideas of energy-efficient cluster-based routing and media access together with application-specific data aggregation to achieve good performance in terms of system lifetime, latency, and application-perceived quality. LEACH includes a new, distributed cluster formation technique that enables self-organization of large numbers of nodes, algorithms for adapting clusters and rotating cluster head positions to evenly distribute the energy load among all the nodes, and techniques to enable distributed signal processing to save communication resources. Our results show that LEACH can improve system lifetime by an order of magnitude compared with general-purpose multihop approaches.

/pdf/an-application-specific-protocol-architecture-for-wireless-1s7y9fiv40.pdf

An application-specific protocol architecture for wireless microsensor networks

Hash tables - which map "keys" onto "values" - are an essential building block in modern software systems. We believe a similar functionality would be equally valuable to large distributed systems. In this paper, we introduce the concept of a Content-Addressable Network (CAN) as a distributed infrastructure that provides hash table-like functionality on Internet-like scales. The CAN is scalable, fault-tolerant and completely self-organizing, and we demonstrate its scalability, robustness and low-latency properties through simulation.

https://www.cs.sjtu.edu.cn/~gchen/course/acn/Reading/CAN.pdf

A scalable content-addressable network

Topology control in a sensor network balances load on sensor nodes and increases network scalability and lifetime. Clustering sensor nodes is an effective topology control approach. We propose a novel distributed clustering approach for long-lived ad hoc sensor networks. Our proposed approach does not make any assumptions about the presence of infrastructure or about node capabilities, other than the availability of multiple power levels in sensor nodes. We present a protocol, HEED (Hybrid Energy-Efficient Distributed clustering), that periodically selects cluster heads according to a hybrid of the node residual energy and a secondary parameter, such as node proximity to its neighbors or node degree. HEED terminates in O(1) iterations, incurs low message overhead, and achieves fairly uniform cluster head distribution across the network. We prove that, with appropriate bounds on node density and intracluster and intercluster transmission ranges, HEED can asymptotically almost surely guarantee connectivity of clustered networks. Simulation results demonstrate that our proposed approach is effective in prolonging the network lifetime and supporting scalable data aggregation.

/pdf/heed-a-hybrid-energy-efficient-distributed-clustering-4c3cjgsfv9.pdf

HEED: a hybrid, energy-efficient, distributed clustering approach for ad hoc sensor networks

Networked sensors-those that coordinate amongst themselves to achieve a larger sensing task-will revolutionize information gathering and processing both in urban environments and in inhospitable terrain. The sheer numbers of these sensors and the expected dynamics in these environments present unique challenges in the design of unattended autonomous sensor networks. These challenges lead us to hypothesize that sensor network coordination applications may need to be structured differently from traditional network applications. In particular, we believe that localized algorithms (in which simple local node behavior achieves a desired global objective) may be necessary for sensor network coordination. In this paper, we describe localized algorithms, and then discuss directed diffusion, a simple communication model for describing localized algorithms.

https://www.cs.jhu.edu/~cs647/class-papers/Sensor%20Nets/estrin.pdf

Next century challenges: scalable coordination in sensor networks

Lichen planus, a chronic autoimmune, mucocutaneous disease affects the oral mucosa (oral lichen planus or OLP) besides the skin, genital mucosa, scalp and nails. An immune mediated pathogenesis is recognized in lichen planus although the exact etiology is unknown. The disease most commonly affects middle-aged females. Oral lichenoid reactions (OLR) which are considered variants of OLP, may be regarded as a disease by itself or as an exacerbation of an existing OLP, by the presence of medication (lichenoid drug reactions) or dental materials (contact hypersensitivity). OLP usually presents as white striations (Wickham's striae), white papules, white plaque, erythema, erosions or blisters. Diagnosis of OLP is established either by clinical examination only or by clinical examination with histopathologic confirmation. Direct immunofluorescence examination is only used as an adjunct to the above method of diagnosis and to rule out specific autoimmune diseases such as pemphigus and pemphigoid. Histopathologic features of OLP and OLR are similar with suggestions of certain discriminatory features by some authors. Topical corticosteroids are the treatment of choice for OLP although several other medications have been studied including retinoids, tacrolimus, cyclosporine and photodynamic therapy. Certain OLP undergo malignant transformation and the exact incidence and mechanisms are still controversial. In this paper, etiopathogenesis, diagnosis, management and malignant transformation of OLP and OLR have been reviewed.

/pdf/oral-lichen-planus-and-lichenoid-reactions-etiopathogenesis-4534fdre4l.pdf

Oral lichen planus and lichenoid reactions: etiopathogenesis, diagnosis, management and malignant transformation

Next Century Challenges: Mobile Networking for Smart Dust

Background Saliva is being studied extensively and is being used for risk assessment, diagnosis and monitoring high-risk behavior and disease progression. A variety of medical conditions and medications are associated with salivary gland hypofunction. The major disadvantage in the use of saliva for health-related purposes is the lack of standardization in saliva collection methods. Methods The authors provide a brief overview of different methods of saliva collection and the advantages and disadvantages associated with each method, as well as of how to assess the salivary flow rate. Results The authors present the complete set up and step-by-step guidelines for the collection of unstimulated and stimulated whole saliva. Conclusions The life expectancy of people will continue to increase with advances in medicine and therapeutic modalities, and the prevalence of salivary gland hypofunction in the elderly population will increase owing to their longevity. The assessment of salivary gland hypo-function will need to be incorporated into everyday clinical practice. Clinical Implications The saliva collection methods outlined in this article can be used by dentists to assess patients at risk of developing diseases and by scientists for scholarly activities.

https://jada.ada.org/article/S0002-8177(14)63880-0/pdf

Measuring salivary flow: Challenges and opportunities

Purpose
Epidemiologic studies on sleep disorders in the USA have mostly focused on specific disorders in specific groups of individuals. Most studies on sleep habits and sleep-related difficulties have focused on children and adolescents. The authors describe the prevalence of the three common physician-diagnosed sleep disorders (insomnia, sleep apnea, and restless legs syndrome (RLS)) by age, gender, and race in the US population. In addition, the authors describe the sleep habits and sleep-related difficulties in carrying routine daily activities. The authors also investigate the impact of the sleep disorders on performing routine daily activities.

/pdf/prevalence-and-impact-of-sleep-disorders-and-sleep-habits-in-2h6psq27rd.pdf

Satish K.S. Kumar

Papers

Next century challenges: scalable coordination in sensor networks

Oral lichen planus and lichenoid reactions: etiopathogenesis, diagnosis, management and malignant transformation

Next Century Challenges: Mobile Networking for Smart Dust

Measuring salivary flow: Challenges and opportunities

Prevalence and impact of sleep disorders and sleep habits in the United States