Reducing Network Energy Consumption using Multidimensional Optimization of LEACH Protocol

The optimized LEACH-focused protocol is proposed to make equal network energy usage and outspread the life cycle. In the first place, the threshold function of the cluster head is adjusted and the technique of division of the network area is configured to change reasonably the size of the clusters, taking account of residual energy and node distance. A sleep mechanism is introduced for intra-cluster transmission to balance the power consumption of nodes. And a new Barycenter Node has been introduced to help the head of the cluster fulfill the transmission task and thus prolong the lifespan. We derived a new formula, considering the angle, energy and distance, in multiple-hop communication between clusters to determine the fitting factor of the next hop. The results of simulations display that the remaining total energy of the optimized LEACH is decreased by 32.6% and the network life cycle respectively increases by around 54%.

Dopamine receptor DOP-1 engages a sleep pathway to modulate swimming in C. elegans

SummaryAnimals require robust yet flexible programs to support locomotion. While it is clear that a variety of processes must be engaged to ensure rhythmic actions, the exact mechanisms remain largely unknown. Here we report a novel pathway that connects the D1-like dopamine receptor DOP-1 with a sleep mechanism to modulate swimming in C. elegans. We show that DOP-1 plays a negative role in sustaining swimming behavior. By contrast, a pathway through the D2-like dopamine receptor DOP-3 negatively regulates the initiation of swimming, but its impact fades quickly over a few minutes. We find that DOP-1 and the GPCR kinase GRK-2 function in the sleep interneuron RIS, where DOP-1 modulates the secretion of a sleep neuropeptide FLP-11. Our genetic studies further show that DOP-1 and FLP-11 act in the same pathway to modulate swimming. Together, these results delineate a functional connection between a dopamine receptor and a sleep program to regulate swimming in C. elegans. The temporal transition between DOP-3 and DOP-1 pathways highlights the dynamic nature of neuromodulation for rhythmic movements that persist over time.HIGHLIGHTSThe D1-like dopamine receptor DOP-1 regulates swimming at 10 minutesAn integrated function of DOP-1 and DOP-3 is required for the continuity of swimmingDOP-1 and GRK-2 act in the sleep neuron RISFLP-11, a neuropeptide that promotes sleep, negatively regulates swimmingIN BRIEFXu et al. investigated genetic programs that modulate swimming behavior in the nematode C. elegans. They identified a functional link that couples a D1-like dopamine receptor to a sleep program that modulates the sustained phase rather than the initial phase of swimming.

Performance Optimization of Cloud Data Centers with a Dynamic Energy-Efficient Resource Management Scheme

As an advanced network calculation mode, cloud computing is becoming more and more popular. However, with the proliferation of large data centers hosting cloud applications, the growth of energy consumption has been explosive. Surveys show that a remarkable part of the large energy consumed in data center results from over-provisioning of the network resource to meet requests during peak demand times. In this paper, we propose a solution to this problem by constructing a dynamic energy-efficient resource management scheme. As a way of saving energy as well as maintaining cloud user’s quality of experience, the scheme presents a multitier cloud architecture by configuring physical machines (PMs) into two pools: a hot (running) pool and a warm (turned on, but in dynamic sleep) pool. Each PM is configured with a resource search engine (RSE) that finds an available virtual machine (VM) for the request, and a synchronous sleep mechanism is introduced to the warm pool. To analyze the end-to-end performance of the cloud system’s service with the proposed scheme, we establish a hybrid queueing system composed of three stochastic submodels by using a matrix-geometric solution. Accordingly, the average latency of requests and the energy-saving rate of the system are derived. Through numerical results, we show the influence of the synchronous sleep mechanism on the system performance. Moreover, from the perspective of economics, we build a system cost function to study the trade-off between different performance measures. An improved Salp Swarm Algorithm (SSA) is presented to minimize the system cost and optimize the sleep parameter.

The Lightweight RFID Grouping-Proof Protocols with Identity Authentication and Forward Security

In many fields, multiple RFID tags are often combined into a group to identify an object. An RFID grouping-proof protocol is utilized to prove the simultaneous existence of a group of tags. However, many current grouping-proof protocols cannot simultaneously provide privacy preserving, forward security, and the authentication between reader/verifier and tags, which are vulnerable to trace attack, privacy leakage, and desynchronization attack. To improve the secure performance of the current grouping-proof protocols, we propose two provable lightweight grouping-proof protocols that provide forward security, identity authentication, and privacy preserving. Our protocols involve a trusted reader and an untrusted reader, respectively. In order to avoid verifying some invalid evidences, our protocols complete the authentication of the verifier to the trusted reader and the verified tags before the verifier verifies the grouping-proof evidence. Each tag uses parallel mode to complete its signature to improve the efficiency of the protocols. Moreover, the activate-sleep mechanism and the filtering operation are proposed to effectively reduce the collision probability and computing load of tags. Our protocols complete the authentication to tags twice by a verifier and a trusted reader, respectively. They can resist various attacks such as eavesdropping, replay, trace, and desynchronization. The protocols are proven to be secure, flexible, and efficient. They only utilize some lightweight operations. Therefore, they are very suitable to the low-cost RFID systems.

Sleep Disorders

Recent research has generated an enormous fund of knowledge about the neurobiology of sleep and wakefulness. Sleeping and waking brain circuits can now be studied by sophisticated neuroimaging techniques that map different areas of the brain during different sleep states and stages. Although the exact biologic functions of sleep are not known, sleep is essential, and sleep deprivation leads to impaired attention and decreased performance. Sleep is also believed to have restorative, conservative, adaptive, thermoregulatory, and consolidative functions. This review discusses the physiology of sleep, including its two independent states, rapid eye movement (REM) and non–rapid eye movement (NREM) sleep, as well as functional neuroanatomy, physiologic changes during sleep, and circadian rhythms. The classification and diagnosis of sleep disorders are discussed generally. The diagnosis and treatment of the following disorders are described: obstructive sleep apnea syndrome, narcolepsy-cataplexy sydrome, idiopathic hypersomnia, restless legs syndrome (RLS) and periodic limb movements in sleep, circadian rhythm sleep disorders, insomnias, nocturnal frontal lobe epilepsy, and parasomnias. Sleep-related movement disorders and the relationship between sleep and psychiatric disorders are also discussed. Tables describe behavioral and physiologic characteristics of states of awareness, the international classification of sleep disorders, common sleep complaints, comorbid insomnia disorders, causes of excessive daytime somnolence, laboratory tests to assess sleep disorders, essential diagnostic criteria for RLS and Willis-Ekbom disease, and drug therapy for insomnia. Figures include polysomnographic recording showing wakefulness in an adult; stage 1, 2, and 3 NREM sleep in an adult; REM sleep in an adult; a patient with sleep apnea syndrome; a patient with Cheyne-Stokes breathing; a patient with RLS; and a patient with dream-enacting behavior; schematic sagittal section of the brainstem of the cat; schematic diagram of the McCarley-Hobson model of REM sleep mechanism; the Lu-Saper “flip-flop” model; the Luppi model to explain REM sleep mechanism; and a wrist actigraph from a man with bipolar disorder. This review contains 14 highly rendered figures, 8 tables, 115 references, and 5 MCQs.

An Optimal Method to Design Wireless Sensor Network Structures

In order to optimize the structure of wireless sensor network, an improved wireless sensor network sleep mechanism is proposed. First, some nodes in the area with too high redundancy are dormant by density control, so that the active nodes are even more distributed. Then, the active node is subjected to circular coverage redundancy decision. Different circumferential coverage decision methods are used for network boundary nodes and non-boundary nodes. As a result, the boundary nodes and non-boundary nodes are well dormant, and the network redundancy is reduced. The simulation results show that the improved dormancy mechanism makes the number of active nodes in the network smaller and more evenly, and the network lifetime is extended on the basis of maintaining the original coverage of the network. Therefore, the proposed method can achieve optimal coverage in wireless sensor networks. The network prolongs network lifetime while ensuring reliable monitoring performance.