Analysis of background factors in marine accidents and incidents caused by watch-keeper drowsiness in Japan

The purpose of this study was to perform a feature extraction of sleep and lifecycle characteristics among watch-keepers involved in marine accidents and incidents. A questionnaire that included attributes of the watch-keeper, amount of sleep, problems related to sleep, fatigue, feeling hiyari-hatto incidents, and the Epworth sleepiness scale (ESS) was administered to a sample of 7,750 watch-keepers (response rate - 21.3%). Watch:keepers have problems related to sleep, such as “once a month or more awaking while sleeping and cannot sleep afterwards”, “once a month or more awaking too early in the morning and cannot sleep afterwards”, “I have been told by my family and colleagues that I snore”, and “I had my breathing stopped while sleeping”. Some watchkeepers indicated “once a month or more feeling hiyari-hatto incidents” The analysis of cargo ships and tankers revealed there was a notable relationship between the situation of “once a month or more feeling hiyari-hatto incidents” and the influence of each “frequency of interrupted sleep”, “sleep delay”, “frequency of interrupted sleep” and ”early morning sleeplessness”. These results suggest that watch-keeper of each ship have problems related to sleep due to sleep and lifecycle characteristics.Проведено аналіз основних особливостей режиму праці, обумовлених несенням вахт на судах різних типів (суховантажі, танкери, прогулянкові судна та ін) за даними анкетування 7750 моряків. Встановлено, що вахтові офіцери відзначають наявність проблем, пов'язаних з різними видами порушень сну (недостатнє загальний час сну за добу, порушення регулярності у наданні часу для сну, позбавлення сну під час вантажних операцій, переривчастий сон та ін.) Показано наявність достовірної взаємозв'язку між характером сну і частотою інцидентів, що призводять до аварійності на флоті.Проведен анализ основных особенностей режима труда, обусловленных несением вахт на судах различных типов (сухогрузы, танкеры, прогулочные суда и др.) по данным анкетирования 7750 моряков. Установлено, что вахтенные офицеры отмечают наличие проблем, связанных с различными видами нарушений сна (недостаточное общее время сна за сутки, нарушение регулярности в предоставлении времени для сна, лишение сна во время грузовых операций, прерывистый сон и др.). Показано наличие достоверной взаимосвязи между характером сна и частотой инцидентов, приводящих к аварийности на флоте

Virtualized Network Graph Design and Embedding Model to Minimize Provisioning Cost

The provisioning cost of a virtualized network (VN) depends on several factors, including the numbers of virtual routers (VRs) and virtual links (VLs), mapping of them on a substrate infrastructure, and routing of data traffic. An existing model, known as the virtual network embedding (VNE) model, determines the embedding of given VN graphs into the substrate infrastructure. When the resource allocation model of the VNE problem is adopted to a single-entity scenario, where a single entity fulfills the roles of both a service provider and an infrastructure provider, an issue of increased costs of VNs and access paths arise. This paper proposes a model for virtualized network graph design and embedding (VNDE) for the single-entity scenario. The VNDE model determines the number of VRs and a VN graph for each request in conjunction with embedding. The VNDE model also determines access paths that connect customer premises and VRs. We formulate the VNDE model as an integer linear programming (ILP) problem. We develop heuristic algorithms for the cases where the ILP problem cannot be solved in practical time. We evaluate the performance of the VNDE model on several networks, including an actual Japanese academic backbone network. Numerical results show that the proposed model designs suitable VN graphs and embeds them according to the volume of traffic demands and access path cost. Compared with the benchmark model, which is based on a classic VNE approach, the proposed model reduces the provisioning cost at most 28.7% in our examined scenarios

Flows Reduction Scheme Using Two MPLS Tags in Software-Defined Network

This paper proposes a scheme to reduce the number of flow entries permanently stored in an OpenFlow switch and the number of configuration messages from a controller in a software-defined network (SDN). In an SDN, a flow table in an OpenFlow switch is used to instruct packets. The flow table consists of flow entries decided by the controller. A flow request is sent from the OpenFlow switch to the controller if the incoming packet does not match any flow entry in the flow table. The controller\u27s central processing unit may be overloaded to handle user requests, since the user requests for different data types have been rapidly increasing. As a result, flow configuration in switches is delayed. Moreover, the control plane may be flooded by configuration messages of those requests. A scheme to permanently keep the flow entries in the switch can reduce the number of requests. However, a large number of permanent flow entries is required. Other switch features may be degraded, since there is not enough memory in the flow table to implement those features. In the proposed scheme, switches in the network are divided into multiple regions. In order to guide packets from sources to destinations, the flow table incorporating the concept of two multiprotocol label switching tags is re-designed. One tag directs a packet from a source switch to an edge switch in the destination region. The other tag directs the packet from that edge switch to another switch in the same region. A mathematical model for the proposed scheme is formulated as an integer linear programming to determine a set of switches in each region so that the total number of permanent flow entries in the network can be minimized. The performance of the proposed scheme is analyzed. Moreover, the proposed scheme is implemented and demonstrated via Japanese Science Information Network 5

ジェームス・クリュス「101日物語」における「語り」の魅力と島の象徴性

関西学院大

Single tag scheme for segment routing in software-defined network

This paper proposes a scheme to reduce a size of a packet header for a segment routing (SR) scheme in a software-defined network (SDN). The SR scheme inserts a segment identification (SID) list into the packet header to indicate a path for the source–destination pair of the packet. The path can be split into different segments to suit the service requirement and the segments are carried by the SID-list whose length increases with the number of segments. This also increases the packet overhead, and an additional packet is needed if the packet length exceeds the maximum transmission unit (MTU). Moreover, it may not be possible to implement SR in SDN due to the limited number of stacked labels provided by the switch vendor. In the proposed scheme, the SID-list is replaced by a single tag to indicate a node edge, called a swapping node. The tag is replaced by a new tag at the swapping node. With this scheme, the size of SID-list is fixed and does not vary with the number of segments, and no additional packets are required. A mathematic model to balance the number of flow entries in each swapping node is introduced by minimizing the maximum number of flow entries in each swapping node over the network. We implement the proposed scheme on the transmission-Japan science information network (SINET5) and demonstrate confirms its functionality

Effects of self-perceived objectivity on hiring decisions : Reexamining the Experiment by Uhlmann and Cohen

Uhlmann and Cohen (2007) argued that self-perceived objectivity increased discrimination against women in hiring decisions; when decision makers have a sense of personal objectivity, they feel entitled to evaluate job applicants based on their gender stereotypical beliefs. We reexamined Experiment 2 by Uhlmann and Cohen (2007) with a sample of male university students in Japan. Contrary to their results, i.e., male participants high in stereotypic beliefs, primed with a sense of objectivity, gave male applicants more positive hiring evaluations than female applicants, we did not find any significant effects. The effects of self-perceived objectivity should be reexamined in future research considering factors, such as a sense of power, duration of effects after being primed, and participants’ sex.本論文は，2016年度に広島大学教育学部で開講した「心理学課題演習」において，第1著者の指導により第2著者から第5著者までが実施した研究をもとに執筆した。研究の一部は第2著者から第5著者により第72回中国四国心理学会学部生研究発表会において報告された。また，本研究の一部はJSPS科研費（JP26380844）による助成を受けたものである

A multi-center study on low-frequency rTMS combined with intensive occupational therapy for upper limb hemiparesis in post-stroke patients

<p>Abstract</p> <p>Background</p> <p>Both low-frequency repetitive transcranial magnetic stimulation (rTMS) and intensive occupational therapy (OT) have been recently reported to be clinically beneficial for post-stroke patients with upper limb hemiparesis. Based on these reports, we developed an inpatient combination protocol of these two modalities for the treatment of such patients. The aims of this pilot study were to confirm the safety and feasibility of the protocol in a large number of patients from different institutions, and identify predictors of the clinical response to the treatment.</p> <p>Methods</p> <p>The study subjects were 204 post-stroke patients with upper limb hemiparesis (mean age at admission 58.5 ± 13.4 years, mean time after stroke 5.0 ± 4.5 years, ± SD) from five institutions in Japan. During 15-day hospitalization, each patient received 22 treatment sessions of 20-min low-frequency rTMS and 120-min intensive OT daily. Low-frequency rTMS of 1 Hz was applied to the contralesional hemisphere over the primary motor area. The intensive OT, consisting of 60-min one-to-one training and 60-min self-exercise, was provided after the application of low-frequency rTMS. Fugl-Meyer Assessment (FMA) and Wolf Motor Function Test (WMFT) were performed serially. The physiatrists and occupational therapists involved in this study received training prior to the study to standardize the therapeutic protocol.</p> <p>Results</p> <p>All patients completed the protocol without any adverse effects. The FMA score increased and WMFT log performance time decreased significantly at discharge, relative to the respective values at admission (change in FMA score: median at admission, 47 points; median at discharge, 51 points; p < 0.001. change in WMFT log performance time: median at admission, 3.23; median at discharge, 2.51; p < 0.001). These changes were persistently seen up to 4 weeks after discharge in 79 patients. Linear regression analysis found no significant relationship between baseline parameters and indexes of improvement in motor function.</p> <p>Conclusions</p> <p>The 15-day inpatient rTMS plus OT protocol is a safe, feasible, and clinically useful neurorehabilitative intervention for post-stroke patients with upper limb hemiparesis. The response to the treatment was not influenced by age or time after stroke onset. The efficacy of the intervention should be confirmed in a randomized controlled study including a control group.</p