Search results for "intensity"
showing 10 items of 1091 documents
A Time-Non-Homogeneous Double-Ended Queue with Failures and Repairs and Its Continuous Approximation
2018
We consider a time-non-homogeneous double-ended queue subject to catastrophes and repairs. The catastrophes occur according to a non-homogeneous Poisson process and lead the system into a state of failure. Instantaneously, the system is put under repair, such that repair time is governed by a time-varying intensity function. We analyze the transient and the asymptotic behavior of the queueing system. Moreover, we derive a heavy-traffic approximation that allows approximating the state of the systems by a time-non-homogeneous Wiener process subject to jumps to a spurious state (due to catastrophes) and random returns to the zero state (due to repairs). Special attention is devoted to the cas…
Smart Wireless Sensor Networks and Biometric Authentication for Real Time Traffic Light Junctions Management
2013
The main challenge of intelligent transportation systems (ITS) is to deal with ‘real-time’ information to improve vehicular traffic management. Road data can be processed and used for dynamic traffic light management in order to reduce waiting times in queues. This paper proposes an innovative distributed architecture based on a wireless sensor network (WSN) with a network coordinator providing remote and ubiquitous authentication module for managing unexpected events. The architecture is completed by a dynamic module for street priority management depending on traffic rate. Many experimental trials have been carried out considering three different levels of traffic intensity to prove the e…
Working hours – tracking the current and future trends
2021
It is important to track the trends of future working hours, since working hours have strong associations to everyday life and work-life interaction, but also to health. In this paper we aim to track the current and future trends in working hours. We discuss the trends through the key dimensions of working hours: the length, timing, tempo and autonomy. We also consider the role of current trends of spatial changes of work. Changes in working time patterns are fostered by several driving factors: globalization and business restructuring challenging the current work organizations, new information technologies, demographic and climate change and the current and future pandemics. The past and c…
The impact of periodic interviews on unemployment duration : Evidence from the 2017 Finnish reform
2023
In 2017, a Finnish policy reform intensified the Public Employment Services' practice of periodically interviewing unemployed jobseekers. This study used high-quality administrative data to analyse the effect of interviews on unemployment duration. We used a difference-in-differences approach that exploited regional variations in treatment intensity. Our results show that a 10 percentage point increase in interview probability increased the monthly hazard rate of employment by 3.1 per cent, with the effect being strongest among jobseekers aged 25–34 and jobseekers with a low education level. Also, our results demonstrate a strong effect on participation in active labour market programmes. p…
Nonlinear black-box models for short-term forecasting of air temperature in the town of Palermo
2011
Weather data are crucial to correctly design buildings and their heating and cooling systems and to assess their energy performances. In the intensely urbanized towns the effect of climatic parameters is further emphasized by the Urban Heat Island (UHI) phenomenon, known as the increase in the air temperature of urban areas, compared to the one measured in the extra-urban areas. The analysis of the heat island needs detailed local climate data which can be collected only by a dedicated weather monitoring system. The Department of Energy and Environmental Researches of the University of Palermo (Italy) has built up a weather monitoring system that works 24 hours per day and makes data availa…
Female reproductive factors are associated with objectively measured physical activity in middle-aged women
2017
Physical activity improves health and may delay the onset of several chronic diseases. For women in particular, the rate of these diseases accelerates at middle age; therefore it is important to identify the determinants of health-enhancing physical activity during midlife in this population. In this study, we focused on determinants that are unique to the female sex, such as childbearing and menopause. The main objective was to characterize the level of physical activity and differences between active and inactive middle-aged Finnish women. In addition, we examined the association of physical activity with female reproductive factors at midlife. The study population consisted of 647 women …
Comparison of inter-trial recovery times for the determination of critical power and W' in cycling
2017
Critical Power (CP) and W’ are often determined using multi-day testing protocols. To investigate this cumbersome testing method, the purpose of this study was to compare the differences between the conventional use of a 24-h inter-trial recovery time with those of 3 h and 30 min for the determination of CP and W’. Methods: 9 moderately trained cyclists performed an incremental test to exhaustion to establish the power output associated with the maximum oxygen uptake (p V O2max), and 3 protocols requiring time-to-exhaustion trials at a constant work-rate performed at 80%, 100% and 105% of p VO2max. Design: Protocol A utilised 24-h inter-trial recovery (CP24/W’24), protocol B utilised 3-h in…
Vascular Risk Factors in Mild Cognitive Impairment Subtypes
2007
<i>Background and Aim:</i> To investigate the role of vascular risk factors in different subtypes of mild cognitive impairment (MCI) in a multicentric, clinic-based, cross-sectional study. <i>Methods:</i> Two-hundred and seven subjects with MCI were included in the study: 33 with single non-memory MCI (snmMCI), 42 with multiple-domain amnestic MCI (mdMCI-a) and 132 with amnestic MCI (aMCI). Several clinical vascular risk factors and magnetic resonance imaging (MRI) brain lesions were evaluated. <i>Results:</i> snmMCI showed a higher frequency of ischaemic heart disease and of transient ischaemic attack (TIA)/stroke, a higher Hachinski ischaemic score and …
Adventiv-Embryonen aus Nicotiana-kallus, der bei Hohen Lichtintensitäten Kultiviert wurde
1965
The formation of embryonic structures in Nicotiana callus tissue has been reported. High intensity of light as a stimulating factor in differentiation is discussed.
Neuromuscular fatigue after short-term maximal run in child, youth, and adult athletes
2013
Johdanto ja tutkimuksen tavoite. Aikaisempien tutkimusten perusteella on havaittu että esipuberteetti ikäiset lapset väsyvät vähemmän ja palautuvat nopeammin kuin aikuiset kovatehoisten urheilusuoritusten yhteydessä. Nuoren urheilijan kypsymiseen liittyvät muutokset perifeerisissä ja hermostollisissa väsymysmekanismeissa ovat kuitenkin vielä selvittämättä. Tämän tutkimuksen tavoitteena on tuottaa uutta tietämystä iän ja kypsymisen vaikutuksista perifeeristen ja hermostollisten mekanismien rooliin 50 s maksimaalisessa juoksusuorituksessa. Menetelmät: Tutkimukseen osallistui 24 miespuolista koehenkilöä jotka jaettiin kolmeen ikäryhmään: Lapset (N = 8; 11.9 ± 1.4 v), Nuoret (N = 8; 14.9 ± 1.1 …