Wyniki wyszukiwania - BazTech

1

Whose fault is it? Correctly attributing outages in cloud services

Adriani Matteo, Naldi Maurizio

Annals of Computer Science and Information Systems

|

2019

|

Vol. 18

433--440

EN

Cloud availability is a major performance parameter in cloud Service Level Agreements (SLA). Its correct evaluation is essential to SLA enforcement and possible litigation issues. Current methods fail to correctly identify the fault location, since they include the network contribution. We propose a procedure to identify the failures actually due to the cloud itself and provide a correct cloud availability measure. The procedure employs tools that are freely available, i.e. traceroute and whois, and arrives at the availability measure by first identifying the boundaries of the cloud. We evaluate our procedure by testing it on three major cloud providers: Google Cloud, Amazon AWS, and Rackspace. The results show that the procedure arrives at a correct identification in 95% of cases. The cloud availability obtained in the test after correct identification lies between 3 and 4 nines for the three platforms under test.

2

Monitorowanie usterek w układzie EGR silnika HDI RHR

Cieślikowski B., Cygnar M., Ślipek Z., Budzik G.

Logistyka

|

2015

|

nr 5

85--91, CD1

PL

W artykule omówiony został proces lokalizacji usterek w układzie EGR z wykorzystaniem listy kodów w systemie OBD II. Analizując procesy wymiany ciepła i masy na odcinku układu dolotowego silnika zwrócono uwagę na szereg uproszczeń w opisie formalnym, prowadzących do ustalenia przedziału tolerancji chwilowej wartości stopnia recyrkulacji. Posłużono się przykładem monitorowania układu EGR pojazdów z silnikiem HDi RHR. Analiza funkcjonalna układu oraz znajomość procedur diagnostycznych pojazdu stanowi właściwe ukierunkowanie procesu lokalizacji uszkodzeń.

EN

In the article was discussed the location faults in the agreement EGR using list of fault codes OBD II. Analyzing the processes of heat and mass transfer over a distance of the engine intake system, called attention to a number of simplifications in the description of formal, leading to establish a temporary tolerance range of recirculation. As an example was used the monitoring system EGR of vehicle with an HDi RHR engine. Functional analysis system and knowledge diagnostic procedures, using selected recording car operating parameters, is the appropriate focus in the process location damage.

3

Fault location in the outer sheath of power cables

Wang Q., Tang Ch., Wu G., Chen G.

Journal of Power Technologies

|

2014

|

Vol. 94, nr 4

250--258

EN

With the development of power systems in recent years, the total amount of power cables in operation has increased greatly, and there are growing reports of cable failure. Cable failures may be due to various intrinsic or extrinsic factors and can lead to massive economic loss. With regard to high-voltage cables, such as 110 kV power cables, there are very few accurate reports on the actual fault observed. This article first analyses the possible causes of power cable outer sheath failure. It then introduces the bridge and step voltage methods, which are traditionally used for cable fault locating, and describes a new method for accurate fault locating in 110 kV cables, which uses the bridge method to pre-locate the fault and then the step voltage method to accurately determine the precise fault locating. Field testing confirms the applicability of the new method for accurate fault locating in 110 kV power cables. The results shown in this article may provide a good reference for the development of future research in related fields.