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Phasor-Based Assessment for Harmonic Sources in Distribution Networks
Phasor-based interdependencies of multiple harmonic sources, especially Distributed Energy Resources, on distribution networks are analyzed in this paper. A new index, Phasor Harmonic Index (IPH), is proposed by the authors. IPH considers both harmonic source magnitude and phase angle for different harmonic orders. Other commonly used harmonic indices are based solely on magnitude of waveforms. A very detailed model of a distribution network is used in the harmonic assessment. With the help of the detailed distribution network model, the phase couplings and the phase balancing impacts on harmonic propagation between three phases are investigated. Moreover, effects of harmonic source phase angle deviations are analyzed at both the customer side and the substation side. This paper investigates the importance of phase angles in harmonic assessment and how distribution netw
Étude S.AGES : recueil et suivi de nouveaux cas de syndromes d’apnées obstructives au cours du sommeil (SAOS), chez des sujets âgés de plus de 70 ans, diagnostiqués dans les structures de pneumologie et de gériatrie
RATIONALE:
S.AGES is a prospective cohort of >70-years-old patients with obstructive sleep apnea syndrome having been diagnosed in a pulmonary or a geriatric medical unit.
OBJECTIVES:
The main objective of S.AGES is to get a description of older patients with OSAS in France. The secondary objectives will be to prospectively describe the management and the treatment of these patients, to describe their 5-years outcome as compared to younger patients in the literature. It will also contribute to better characterize the compliance and tolerance of the treatment and the incidence of comorbidities like respiratory diseases and cardiovascular disorders.
METHODS:
All consecutive≥70-years-old patients having received a diagnosis of OSAS (after polygraphy or polysomnography) will be included in the study. All patients will be followed in a pulmonary or a geriatric department.
EXPECTED RESULTS:
S.AGES should better characterize the OSAS in the elderly patients, the specific management of this disease and its related risk factors. It may also identify the 5-years mortality and morbidity rates in this population
Evaluating a mesoscale atmosphere model and a satellite-based algorithm in estimating extreme rainfall events in northwestern Turkey
Quantitative precipitation estimates are obtained with more uncertainty under
the influence of changing climate variability and complex topography from
numerical weather prediction (NWP) models. On the other hand, hydrologic
model simulations depend heavily on the availability of reliable
precipitation estimates. Difficulties in estimating precipitation impose an
important limitation on the possibility and reliability of hydrologic
forecasting and early warning systems. This study examines the performance of
the Weather Research and Forecasting (WRF) model and the Multi Precipitation
Estimates (MPE) algorithm in producing the temporal and spatial
characteristics of the number of extreme precipitation events observed in the
western Black Sea region of Turkey. Precipitation derived from WRF model with
and without the three-dimensional variational (3DVAR) data assimilation scheme
and MPE algorithm at high spatial resolution (5 km) are compared with gauge
precipitation. WRF-derived precipitation showed capabilities in capturing the
timing of precipitation extremes and to some extent the spatial distribution
and magnitude of the heavy rainfall events, whereas MPE showed relatively weak
skills in these aspects. WRF skills in estimating such precipitation
characteristics are enhanced with the application of the 3DVAR scheme. Direct
impact of data assimilation on WRF precipitation reached up to 12% and at
some points there is a quantitative match for heavy rainfall events, which
are critical for hydrological forecasts
Dynamic lot sizing and tool management in automated manufacturing systems
Cataloged from PDF version of article.The overall aim of this study is to show that there is a critical interface between the lot sizing and tool
management decisions, and these two problems cannot be viewed in isolation. We propose "ve alternative
algorithms to solve lot sizing, tool allocation and machining conditions optimization problems simultaneously.
The "rst algorithm is an exact algorithm which "nds the global optimum solution, and the others
are heuristics equipped with a look-ahead mechanism to guarantee at least local optimality. The computational
results indicate that the amount of improvement is statistically signi"cant for a set of randomly
generated problems. The magnitude of cost savings is dependent on the system parameters
Bridging the gap between nanowires and Josephson junctions: a superconducting device based on controlled fluxon transfer across nanowires
The basis for superconducting electronics can broadly be divided between two
technologies: the Josephson junction and the superconducting nanowire. While
the Josephson junction (JJ) remains the dominant technology due to its high
speed and low power dissipation, recently proposed nanowire devices offer
improvements such as gain, high fanout, and compatibility with CMOS circuits.
Despite these benefits, nanowire-based electronics have largely been limited to
binary operations, with devices switching between the superconducting state and
a high-impedance resistive state dominated by uncontrolled hotspot dynamics.
Unlike the JJ, they cannot increment an output through successive switching,
and their operation speeds are limited by their slow thermal reset times. Thus,
there is a need for an intermediate device with the interfacing capabilities of
a nanowire but a faster, moderated response allowing for modulation of the
output. Here, we present a nanowire device based on controlled fluxon
transport. We show that the device is capable of responding proportionally to
the strength of its input, unlike other nanowire technologies. The device can
be operated to produce a multilevel output with distinguishable states, which
can be tuned by circuit parameters. Agreement between experimental results and
electrothermal circuit simulations demonstrates that the device is classical
and may be readily engineered for applications including use as a multilevel
memory
Principles of practice parameters for the treatment of sleep disordered breathing in the elderly and frail elderly: the consensus of the International Geriatric Sleep Medicine Task Force
Sleep disordered breathing (SDB) is a leading cause of morbidity worldwide. Its prevalence increases with age. Due to the demographic changes in industrial societies, pulmonologists and sleep physicians are confronted with a rapidly growing number of elderly SDB patients. For many physicians, it remains unclear how current guidelines for SDB management apply to elderly and frail elderly patients. The goal of this consensus statement is to provide guidance based on published evidence for SDB treatment in this specific patient group.
Clinicians and researchers with expertise in geriatric sleep medicine representing several countries were invited to participate in a task force. A literature search of PubMed from the past 12 years and a systematic review of evidence of studies deemed relevant was performed.
Recommendations for treatment management of elderly and frail elderly SDB patients based on published evidence were formulated via discussion and consensus.
In the last 12 years, there have been surprisingly few studies examining treatment of SDB in older adults and even fewer in frail older adults. Studies that have been conducted on the management of SDB in the older patient population were rarely stratified for age. Studies in SDB treatment that did include age stratification mainly focused on middle-aged and younger patient groups. Based on the evidence that is available, this consensus statement highlights the treatment forms that can be recommended for elderly SDB patients and encourages treatment of SDB in this large patient group
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