PCN based admission control for autonomic video quality differentiation: design and evaluation

The popularity of multimedia services has introduced important new challenges for broadband access network management. As these services are very prone to network anomalies such as packet loss and jitter, accurate admission control mechanisms are needed to avoid congestion. Traditionally, centralized admission control mechanisms often underperform in combination with multimedia services, as they fail to effectively characterize the amount of needed resources. Recently, measurement based admission control mechanisms have been proposed such as the IETF Pre-Congestion Notification (PCN) mechanism, where the network load is measured at each intermediate node and signaled to the edge, where the admittance decision takes place. In this article, we design a PCN based admission control mechanism, optimized for protecting bursty traffic such as video services, which is currently not studied in the PCN working group. We evaluated and identified the effect of PCN's configuration in protecting bursty traffic. The proposed admission control mechanism features three main improvements to the original PCN mechanism: first, it uses a new measurement algorithm, which is easier to configure for bursty traffic. Second, it allows to automatically adapt PCN's configuration based on the traffic characteristics of the current sessions. Third, it introduces the differentiation between video quality levels to achieve an admission decision per video quality level of each request. The mechanism has been extensively evaluated in a packet switched simulation environment, which shows that the novel admission control mechanism is able to protec

The plan of the search for Antarctic Meteorites on the Nansen Ice Field by the Joint Expedition between JARE-54 and BELARE 2012-2013.

第3回極域科学シンポジウム/第35回南極隕石シンポジウム 11月29日（木）、30日（金） 国立国語研究所 2階講

Diaschisis cérébral croisé par lésion cérébelleuse: rôle du cervelet dans les fonctions mentales.

In 3 patients with a stroke limited to the posterior fossa, regional cerebral blood Flows were measured by the 133 Xe inhalation method (the first two cases) or by the SPECT with HMPAO method (the third case). The first patient had a median and paramedian hematoma of the left cerebellar hemisphere and the left dorsolateral portion of the pons. Remote cerebral hypoperfusion, measured 3 months later, was observed in both frontal premotor regions (but more marked in the right hemisphere) and in a circumscribed area of the right temporal region. The second patient had a right-sided ischaemic lesion of the anterior cerebellar lobe and the mesencephalic tectum. Contralateral parietal and rolandic hypoperfusion, measured 7 weeks after the stroke, was observed. The third patient had on old infarct of the right cerebellar hemisphere. The SPECT, measured 17 years later, showed a left fronto-parieto-temporal hypoperfusion and the absence of perfusion in the right cerebellar hemisphere. Preliminary data of neuropsychological assessment in our patients disclosed impairment in visuo-spatial and constructive organization, memory and learning compatible with the published findings in some patients and animals with predominantly cerebellar damage. These interesting findings should be confirmed in a large number of patients with age, sex, and sociocultural matched controls. In the absence of supratentorial insult, and during the hemodynamical stable phase, crossed cerebello-cerebral diaschisis is suggested in our 3 patients. Although it is too early to draw definite conclusions, our findings may: (1) confirm the functional interconnections between the cerebellum and the cerebrum in man and (2) provide functional basis for the behavioral function impairment reported in patients with cerebellar insult. Further rCBF, metabolism, and pathologic studies on this subject are required to elucidate this issue.SCOPUS: re.jinfo:eu-repo/semantics/publishe

Social capital and social inequality in adolescents’ health in 601 Flemish communities: a multilevel analysis

Although it is widely acknowledged that community social capital plays an important role in young people’s health, there is limited evidence on the effect of community social capital on the social gradient in child and adolescent health. Using data from the 2005e2006 Flemish (Belgium) Health Behavior among School-aged Children survey (601 communities, n = 10,915), this study investigated whether community social capital is an independent determinant of adolescents’ perceived health and well-being after taking account of individual compositional characteristics (e.g. the gender composition within a certain community). Multilevel statistical procedures were used to estimate neighborhood effects while controlling for individual level effects. Results show that individual level factors (such as family affluence and individual social capital) are positively related to perceived health and well-being and that community level social capital predicted health better than individual social capital. A significant complex interaction effect was found, such that the social gradient in perceived health and well-being (i.e. the slope of family affluence on health) was flattened in communities with a high level of community social capital. Furthermore it seems that socioeconomic status differences in perceived health and well-being substantially narrow in communities where a certain (average) level of community social capital is present. This should mean that individuals living in communities with a low level of community social capital especially benefit from an increase in community social capital. The paper substantiates the need to connect individual health to their meso socioeconomic context and this being intrinsically within a multilevel framework.status: publishe