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Shigeru Kashihara - One of the best experts on this subject based on the ideXlab platform.

  • a morphogenetic and evolutionary approach to regulating wireless access points for energy efficient and reliable connection services
    Congress on Evolutionary Computation, 2015
    Co-Authors: Kei Ohnishi, Kazuya Tsukamoto, Shigeru Kashihara
    Abstract:

    We propose a method for regulating wireless access points (APs) that is based on mechanisms of biological development and evolution. The purpose of the proposed regulation is to simultaneously achieve power savings in the APs and achieve reliable connection services through the APs better, which is shown to be a trade-off relationship in this study. The regulation target is the Cycle time at which each AP enters the power-off state, which is referred to as the Sleep Cycle time. Biological development mechanisms form bodies of a variety of shapes using different genomes as design information, and these genomes are modified evolutionarily. Similarly, in the present study, a method inspired by biological development forms a variety of the Sleep Cycle times of APs, and an evolutionary method modifies the parameter values of the method inspired by the biological development in order to obtain better configurations of the APs. In addition, the regulation method is able to configure APs in a distributed manner without knowing global information; the total number of APs, their locations, or their identifiers, which is actually suitable for the situation assumed in the present study, in which APs are established and removed freely by their owners and AP users freely appear. Simulation results show that the proposed method is capable of exploring the tradeoff relationship between the amount of consumed power of the APs and the reliability of connection services in terms of momentary achievement by regulating APs, but yields highly varying regulation results along time.

  • CEC - A morphogenetic and evolutionary approach to regulating wireless access points for energy-efficient and reliable connection services
    2015 IEEE Congress on Evolutionary Computation (CEC), 2015
    Co-Authors: Kei Ohnishi, Kazuya Tsukamoto, Shigeru Kashihara
    Abstract:

    We propose a method for regulating wireless access points (APs) that is based on mechanisms of biological development and evolution. The purpose of the proposed regulation is to simultaneously achieve power savings in the APs and achieve reliable connection services through the APs better, which is shown to be a trade-off relationship in this study. The regulation target is the Cycle time at which each AP enters the power-off state, which is referred to as the Sleep Cycle time. Biological development mechanisms form bodies of a variety of shapes using different genomes as design information, and these genomes are modified evolutionarily. Similarly, in the present study, a method inspired by biological development forms a variety of the Sleep Cycle times of APs, and an evolutionary method modifies the parameter values of the method inspired by the biological development in order to obtain better configurations of the APs. In addition, the regulation method is able to configure APs in a distributed manner without knowing global information; the total number of APs, their locations, or their identifiers, which is actually suitable for the situation assumed in the present study, in which APs are established and removed freely by their owners and AP users freely appear. Simulation results show that the proposed method is capable of exploring the tradeoff relationship between the amount of consumed power of the APs and the reliability of connection services in terms of momentary achievement by regulating APs, but yields highly varying regulation results along time.

  • SASO Workshops - Self-configuration of Wireless Access Points Based on Mechanisms of Biological Development and Evolution
    2010 Fourth IEEE International Conference on Self-Adaptive and Self-Organizing Systems Workshop, 2010
    Co-Authors: Kei Ohnishi, Kazuya Tsukamoto, Shigeru Kashihara
    Abstract:

    We propose a method for self-configuration of wireless access points (APs) that is inspired by mechanisms of biological development and evolution. The purpose of the proposed configuration is to simultaneously achieve power savings in the APs and achieve reliable connection services through the APs. The configuration target is the Cycle time at which each AP enters the power-off state, which is referred to as the Sleep Cycle time. Biological development mechanisms form bodies of a variety of shapes using different genomes as design information, and these genomes are modified evolutionarily. Similarly, in the present study, a method inspired by biological development forms a variety of the Sleep Cycle times of APs, and an evolutionary method modifies the parameter values of the method inspired by the biological development in order to obtain better configurations of the APs. In addition, the regulation method is able to configure APs in a distributed manner without knowing global information, the total number of APs, their locations, or their identifiers, which is actually suitable for the situation assumed in the present study, in which APs are established and removed freely by their owners and AP users freely appear. Simulation results suggest that the proposed method is able to achieve power savings and reliable connection services under several assumptions.

Elizabeth B. Klerman - One of the best experts on this subject based on the ideXlab platform.

  • arousal state feedback as a potential physiological generator of the ultradian rem nrem Sleep Cycle
    Journal of Theoretical Biology, 2013
    Co-Authors: Andrew J. K. Phillips, P.a. Robinson, Elizabeth B. Klerman
    Abstract:

    Abstract Human Sleep episodes are characterized by an approximately 90-min ultradian oscillation between rapid eye movement (REM) and non-REM (NREM) Sleep stages. The source of this oscillation is not known. Pacemaker mechanisms for this rhythm have been proposed, such as a reciprocal interaction network, but these fail to account for documented homeostatic regulation of both Sleep stages. Here, two candidate mechanisms are investigated using a simple model that has stable states corresponding to Wake, REM Sleep, and NREM Sleep. Unlike other models of the ultradian rhythm, this model of Sleep dynamics does not include an ultradian pacemaker, nor does it invoke a hypothetical homeostatic process that exists purely to drive ultradian rhythms. Instead, only two inputs are included: the homeostatic drive for Sleep and the circadian drive for Wake. These two inputs have been the basis for the most influential Sleep/Wake models, but have not previously been identified as possible ultradian rhythm generators. Using the model, realistic ultradian rhythms are generated by arousal state feedback to either the homeostatic or circadian drive. For the proposed ‘homeostatic mechanism’, homeostatic pressure increases in Wake and REM Sleep, and decreases in NREM Sleep. For the proposed ‘circadian mechanism’, the circadian drive is up-regulated in Wake and REM Sleep, and is down-regulated in NREM Sleep. The two mechanisms are complementary in the features they capture. The homeostatic mechanism reproduces experimentally observed rebounds in NREM Sleep duration and intensity following total Sleep deprivation, and rebounds in both NREM Sleep intensity and REM Sleep duration following selective REM Sleep deprivation. The circadian mechanism does not reproduce Sleep state rebounds, but more accurately reproduces the temporal patterns observed in a normal night of Sleep. These findings have important implications in terms of Sleep physiology and they provide a parsimonious explanation for the observed ultradian rhythm of REM/NREM Sleep.

Pier Luigi Parmeggiani - One of the best experts on this subject based on the ideXlab platform.

  • Hypothalamic homeothermy across the ultradian Sleep Cycle.
    Archives Italiennes De Biologie, 1995
    Co-Authors: Pier Luigi Parmeggiani
    Abstract:

    In the ambient thermal zone for the vasomotor regulation of body temperature hypothalamic temperature changes across the states of the ultradian Sleep Cycle are the result of state-dependent heat production-heat loss imbalances affecting the temperature of the arterial blood perfusing the brain. However, the changes in arterial blood temperature are efficiently buffered, at a low energetic cost, by the thermal inertia of the mass of body water. Thus, the oscillations in hypothalamic temperature are maintained within a width of a few tenths of a degree and are so small as to be subliminal as thermal feedback stimuli for thermoregulatory responses. This passive hypothalamic homeothermy would support the hypothesis that a phylogenetic pressure was operative early on in mammals in order to limit the duration of the ultradian Sleep Cycle so as to fit the thermal inertia of the different masses of body water in mammals of different sizes.

  • Postural and sympathetic influences on brain cooling during the ultradian wake-Sleep Cycle.
    Brain Research, 1995
    Co-Authors: Adele Azzaroni, Pier Luigi Parmeggiani
    Abstract:

    Abstract The influence of posture and tonic vasoconstrictor sympathetic outflow on systemic (ear pinna-environment) and selective (carotid rete-venous plexus) heat exchange underlying brain cooling was studied in cats chronically implanted with EEG and EMG electrodes, and transducers that measured hypothalamic, pontine and ear pinna temperatures across the ultradian wake-Sleep Cycle in a thermoneutral environment. Transmural pressure on heat exchanger vasculature was varied by keeping the animal's head above or at heart level. The vasoconstrictor sympathetic outflow to heat exchanger vasculature was varied both by keeping the animal's abdomen cool or warm and by means of bilateral common carotid ligature. The results show that a rise in transmural pressure enhanced selective brain cooling and weakens systemic brain cooling. An increase in tonic vasoconstrictor sympathetic outflow decreases both systemic and selective brain cooling.

  • Thermoregulation and Control of the Ultradian Wake-Sleep Cycle
    Why We Nap, 1992
    Co-Authors: Pier Luigi Parmeggiani
    Abstract:

    In this chapter the relationship between temperature and wake-Sleep regulation is considered primarily with respect to the ultradian wake-Sleep Cycle, that is, to the single sequence of wakefulness, synchronized Sleep (NREM), and desynchronized Sleep (REM) episodes. The issue is whether the influence of temperature on the wake-Sleep Cycle is either nonspecific, as a result of thermal comfort or stress influences, or specific, as due to the activity of thermoregulatory mechanisms. The experimental evidence (cf. Parmeggiani, 1987) shows that positive (warm) or negative (cold) thermal loads induce selective changes in the wake-Sleep Cycle. This occurs along with the overall increase in circadian waking or Sleeping times characterizing the behavioral responses to thermal stress or comfort, respectively. Actually, such changes consist of selective depression or enhancement of single Sleep stages in terms of duration and/or frequency. This shows that specific alterations are elicited by temperature in the mechanisms controlling the wake-Sleep ultradian periodicity. In this respect, it is useful to consider whether the behavioral and autonomic thermoregulatory responses are either consistent or inconsistent with the behavioral and autonomic changes of Sleep. On this basis, it is possible to understand why positive or negative thermal loads influence the ultradian wake-Sleep Cycle in so many ways.

  • Relationship between cAMP concentration in anterior hypothalamic-preoptic region and the ultradian wake-Sleep Cycle.
    Journal of the Autonomic Nervous System, 1990
    Co-Authors: Roberto Amici, Luciano Fadiga, Emanuele Perez, Giovanni Zamboni, Pier Luigi Parmeggiani
    Abstract:

    Abstract In the rat anterior hypothalamic-preoptic region adenosine 3′:5′-cyclic monophosphate concentration changes during the ultradian wake-Sleep Cycle. The administration of dl -propranolol and the exposure to low ambient temperature decreased the nucleotide concentration and also modified the wake-Sleep Cycle. This suggests that in this region a biochemical correlation exists with different functional states.

Kei Ohnishi - One of the best experts on this subject based on the ideXlab platform.

  • a morphogenetic and evolutionary approach to regulating wireless access points for energy efficient and reliable connection services
    Congress on Evolutionary Computation, 2015
    Co-Authors: Kei Ohnishi, Kazuya Tsukamoto, Shigeru Kashihara
    Abstract:

    We propose a method for regulating wireless access points (APs) that is based on mechanisms of biological development and evolution. The purpose of the proposed regulation is to simultaneously achieve power savings in the APs and achieve reliable connection services through the APs better, which is shown to be a trade-off relationship in this study. The regulation target is the Cycle time at which each AP enters the power-off state, which is referred to as the Sleep Cycle time. Biological development mechanisms form bodies of a variety of shapes using different genomes as design information, and these genomes are modified evolutionarily. Similarly, in the present study, a method inspired by biological development forms a variety of the Sleep Cycle times of APs, and an evolutionary method modifies the parameter values of the method inspired by the biological development in order to obtain better configurations of the APs. In addition, the regulation method is able to configure APs in a distributed manner without knowing global information; the total number of APs, their locations, or their identifiers, which is actually suitable for the situation assumed in the present study, in which APs are established and removed freely by their owners and AP users freely appear. Simulation results show that the proposed method is capable of exploring the tradeoff relationship between the amount of consumed power of the APs and the reliability of connection services in terms of momentary achievement by regulating APs, but yields highly varying regulation results along time.

  • CEC - A morphogenetic and evolutionary approach to regulating wireless access points for energy-efficient and reliable connection services
    2015 IEEE Congress on Evolutionary Computation (CEC), 2015
    Co-Authors: Kei Ohnishi, Kazuya Tsukamoto, Shigeru Kashihara
    Abstract:

    We propose a method for regulating wireless access points (APs) that is based on mechanisms of biological development and evolution. The purpose of the proposed regulation is to simultaneously achieve power savings in the APs and achieve reliable connection services through the APs better, which is shown to be a trade-off relationship in this study. The regulation target is the Cycle time at which each AP enters the power-off state, which is referred to as the Sleep Cycle time. Biological development mechanisms form bodies of a variety of shapes using different genomes as design information, and these genomes are modified evolutionarily. Similarly, in the present study, a method inspired by biological development forms a variety of the Sleep Cycle times of APs, and an evolutionary method modifies the parameter values of the method inspired by the biological development in order to obtain better configurations of the APs. In addition, the regulation method is able to configure APs in a distributed manner without knowing global information; the total number of APs, their locations, or their identifiers, which is actually suitable for the situation assumed in the present study, in which APs are established and removed freely by their owners and AP users freely appear. Simulation results show that the proposed method is capable of exploring the tradeoff relationship between the amount of consumed power of the APs and the reliability of connection services in terms of momentary achievement by regulating APs, but yields highly varying regulation results along time.

  • SASO Workshops - Self-configuration of Wireless Access Points Based on Mechanisms of Biological Development and Evolution
    2010 Fourth IEEE International Conference on Self-Adaptive and Self-Organizing Systems Workshop, 2010
    Co-Authors: Kei Ohnishi, Kazuya Tsukamoto, Shigeru Kashihara
    Abstract:

    We propose a method for self-configuration of wireless access points (APs) that is inspired by mechanisms of biological development and evolution. The purpose of the proposed configuration is to simultaneously achieve power savings in the APs and achieve reliable connection services through the APs. The configuration target is the Cycle time at which each AP enters the power-off state, which is referred to as the Sleep Cycle time. Biological development mechanisms form bodies of a variety of shapes using different genomes as design information, and these genomes are modified evolutionarily. Similarly, in the present study, a method inspired by biological development forms a variety of the Sleep Cycle times of APs, and an evolutionary method modifies the parameter values of the method inspired by the biological development in order to obtain better configurations of the APs. In addition, the regulation method is able to configure APs in a distributed manner without knowing global information, the total number of APs, their locations, or their identifiers, which is actually suitable for the situation assumed in the present study, in which APs are established and removed freely by their owners and AP users freely appear. Simulation results suggest that the proposed method is able to achieve power savings and reliable connection services under several assumptions.

Andrew J. K. Phillips - One of the best experts on this subject based on the ideXlab platform.

  • arousal state feedback as a potential physiological generator of the ultradian rem nrem Sleep Cycle
    Journal of Theoretical Biology, 2013
    Co-Authors: Andrew J. K. Phillips, P.a. Robinson, Elizabeth B. Klerman
    Abstract:

    Abstract Human Sleep episodes are characterized by an approximately 90-min ultradian oscillation between rapid eye movement (REM) and non-REM (NREM) Sleep stages. The source of this oscillation is not known. Pacemaker mechanisms for this rhythm have been proposed, such as a reciprocal interaction network, but these fail to account for documented homeostatic regulation of both Sleep stages. Here, two candidate mechanisms are investigated using a simple model that has stable states corresponding to Wake, REM Sleep, and NREM Sleep. Unlike other models of the ultradian rhythm, this model of Sleep dynamics does not include an ultradian pacemaker, nor does it invoke a hypothetical homeostatic process that exists purely to drive ultradian rhythms. Instead, only two inputs are included: the homeostatic drive for Sleep and the circadian drive for Wake. These two inputs have been the basis for the most influential Sleep/Wake models, but have not previously been identified as possible ultradian rhythm generators. Using the model, realistic ultradian rhythms are generated by arousal state feedback to either the homeostatic or circadian drive. For the proposed ‘homeostatic mechanism’, homeostatic pressure increases in Wake and REM Sleep, and decreases in NREM Sleep. For the proposed ‘circadian mechanism’, the circadian drive is up-regulated in Wake and REM Sleep, and is down-regulated in NREM Sleep. The two mechanisms are complementary in the features they capture. The homeostatic mechanism reproduces experimentally observed rebounds in NREM Sleep duration and intensity following total Sleep deprivation, and rebounds in both NREM Sleep intensity and REM Sleep duration following selective REM Sleep deprivation. The circadian mechanism does not reproduce Sleep state rebounds, but more accurately reproduces the temporal patterns observed in a normal night of Sleep. These findings have important implications in terms of Sleep physiology and they provide a parsimonious explanation for the observed ultradian rhythm of REM/NREM Sleep.