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排序方式: 共有2395条查询结果,搜索用时 15 毫秒
51.
Saeed Salah Gabriel Maciá-Fernández Jesús E. Díaz-Verdejo Leovigildo Sánchez-Casado 《Journal of Network and Systems Management》2016,24(1):57-91
In Information Technology Service Management (ITSM), network management teams typically use an Incident Ticket System (ITS) as a tool to track, troubleshoot, and coordinate the resolution of network incidents that occur during the daily operation of the network. A well organized ITS may positively impact on the efficiency of the incident management process. Nevertheless, in many cases the handling of tickets by the management team is not completely systematic and may be incoherent and inefficient. This way, irrelevant or redundant tickets for the same incident may be issued, thus creating a redundancy in the system that leads to inefficiencies. In this paper, we suggest a model aimed to correlate redundant tickets in order to reduce the information to a single ticket per incident. We validate the proposed correlation model by evaluating it with two datasets taken from a real ticketing system of a telecommunications network company. Using this model as a basis, we also develop and evaluate a methodology that assesses the efficiency of the management team during the process of tickets creation and management. Based on it, we also get some insights on the performance of the different management groups involved in the ticket creation process. These analyses can be leveraged for improving both the management groups functioning and the policies for the tickets’ creation. 相似文献
52.
53.
Peter Frolkovič Michael Lampe Gabriel Wittum 《Computing and Visualization in Science》2016,18(1):17-29
When a realistic modelling of radioactive contaminant transport in flowing groundwater is required, very large systems of coupled partial and ordinary differential equations can arise that have to be solved numerically. For that purpose, the software package \(r^3t\) is developed in which several advanced numerical methods are implemented to solve such models efficiently and accurately. Using software tools of \(r^3t\) one can treat successfully nontrivial mathematical problems like advection-dominated system with different retardation of transport for each component and with nonlinear Freundlich sorption and/or precipitation. Additionally, long time simulations on complex 3D geological domains using unstructured grids can be realized. In this paper we introduce and summarize the most important and novel features of numerical simulation for radioactive contaminant transport in porous media when using \(r^3t\). 相似文献
54.
Differential protein abundance in promastigotes of nitric oxide‐sensitive and resistant Leishmania chagasi strains 下载免费PDF全文
55.
As telecommunication networks evolve rapidly in terms of scalability, complexity, and heterogeneity, the efficiency of fault localization procedures and the accuracy in the detection of anomalous behaviors are becoming important factors that largely influence the decision making process in large management companies. For this reason, telecommunication companies are doing a big effort investing in new technologies and projects aimed at finding efficient management solutions. One of the challenging issues for network and system management operators is that of dealing with the huge amount of alerts generated by the managed systems and networks. In order to discover anomalous behaviors and speed up fault localization processes, alert correlation is one of the most popular resources. Although many different alert correlation techniques have been investigated, it is still an active research field. In this paper, a survey of the state of the art in alert correlation techniques is presented. Unlike other authors, we consider that the correlation process is a common problem for different fields in the industry. Thus, we focus on showing the broad influence of this problem. Additionally, we suggest an alert correlation architecture capable of modeling current and prospective proposals. Finally, we also review some of the most important commercial products currently available. 相似文献
56.
Christoph Spengler Marcus Huber Andreas Gabriel Beatrix C. Hiesmayr 《Quantum Information Processing》2013,12(1):269-278
Entanglement in high-dimensional many-body systems plays an increasingly vital role in the foundations and applications of quantum physics. In the present paper, we introduce a theoretical concept which allows to categorize multipartite states by the number of degrees of freedom being entangled. In this regard, we derive computable and experimentally friendly criteria for arbitrary multipartite qudit systems that enable to examine in how many degrees of freedom a mixed state is genuine multipartite entangled. 相似文献
57.
Visual Navigation for Mobile Robots: A Survey 总被引:4,自引:0,他引:4
Francisco Bonin-Font Alberto Ortiz Gabriel Oliver 《Journal of Intelligent and Robotic Systems》2008,53(3):263-296
Mobile robot vision-based navigation has been the source of countless research contributions, from the domains of both vision
and control. Vision is becoming more and more common in applications such as localization, automatic map construction, autonomous
navigation, path following, inspection, monitoring or risky situation detection. This survey presents those pieces of work,
from the nineties until nowadays, which constitute a wide progress in visual navigation techniques for land, aerial and autonomous
underwater vehicles. The paper deals with two major approaches: map-based navigation and mapless navigation. Map-based navigation has been in turn subdivided in metric map-based navigation and topological map-based navigation. Our outline to mapless navigation includes reactive techniques based on qualitative characteristics extraction, appearance-based
localization, optical flow, features tracking, plane ground detection/tracking, etc... The recent concept of visual sonar has also been revised.
This work is partially supported by DPI 2005-09001-C03-02 and FEDER funding. 相似文献
58.
Regional anaesthetic procedures are not popular in paediatric anaesthesia in many institutions. However, regional anaesthesia is gaining ground, especially in a "new" concept of balanced paediatric anaesthesia. The decisive argument for the use of regional anaesthesia is the prolongation of pain relief further into the postoperative phase. The minimal haemodynamic and respiratory side effects during epidural and spinal anaesthesia, the reduced narcotic requirement and the potential early mobilisation all speak in favour of practical application of these techniques. Specially adapted needles and catheters have reduced the technical limitations. The use of nerve stimulators has optimize the accuracy of needle and catheter positioning. The use of a nerve stimulator is therefore highly recommended for peripheral nerve blocks in children. On the other hand, the use of regional anaesthesia in children has potential disadvantages, which should be considered. Special knowledge and continuous training are required. Many techniques are time consuming and personnel intensive, at least temporarily, and the combination of general and regional anesthesia exposes the child to the potential risk inherent in both procedures. The aim of this paper is to discuss procedures which have gained favour in paediatric regional anaesthesia during the past few years. These include caudal, epidural and spinal anaesthesia, especially for infants with high narcotic risk, as well as fascia iliaca compartment blocks for lower extremity analgesia and penile blocks. Many peripheral nerve blocks require special experience and therefore are not discussed here, but they are used routinely by specialists in all age groups. Good anatomic and pharmacologic knowledge should be a prerequisite for all physicians who use regional anaesthetic procedures. Continuous training and critical analysis are needed for good results. Only then can such methods be introduced into routine paediatric anaesthetic practice. 相似文献
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60.
Joan?CahillEmail author Nick?Mc?Donald Captain?Gabriel?Losa 《Cognition, Technology & Work》2011,13(1):43-66
A safe flight starts with effective performance of the pre-flight flight planning and briefing task. However, several problems
related to the execution of this task can be identified. Potentially, the introduction of an improved flight plan provides
an opportunity to improve the quality and availability of information provided to Flight Crew, thereby enhancing the quality
of crew briefings. The proposed risk-based, intelligent flight plan is designed from the perspective of the current operational
concept (e.g. fixed routes and ATC managerial role for separation), and associated airline Flight Planning and Dispatch functions.
In this case, the focus is sharing information across specific airline stakeholders (e.g. Flight Operations Management and
Safety functions) and Maintenance, to support a safe and efficient flight operation. Overall, the introduction of this new
flight plan will result in the definition of new operational and organisational processes, along with a new way of performing
the pre-flight, planning and briefing task. It is anticipated that this will impact positively on the operational and safety
outcome of the flight. 相似文献