2,086 research outputs found
Change point detection by Filtered Derivative with p-Value : Choice of the extra-parameters
This paper deals with off-line change point detection using the FDpV method. The Filtered Derivative with p-Value method (FDpV) is a two-step procedure for change point analysis. In the first step, we use the Filtered Derivative (FD) to select a set of potential change points, using its extra-parameters-namely the threshold for detection, and the sliding window size. In the second one, we calculate the p-value for each change point in order to only retain the true positives (true change points) and discard the false positives (false alarms). We give a way to estimate the optimal extra-parameters of the function FD, in order to have the fewest possible false positives and non-detected change points (ND). Indeed, the estimated potential change points may differ slightly from the theoretically correct ones. After setting the extra-parameters, we need to know whether the absence of detection or the false alarm has more impact on the Mean Integrated Square Error (MISE), which prompts us to calculate the MISE in both cases. Finally, we simulate some examples with a Monte-Carlo method to better understand the positive and negative ways the parametrisation can affect the results
A framework for an application based mobile cache consistency method.
In a mobile environment, maintaining cache consistency is challenging. Applying one type of consistency levels either strict or weak is not suitable all the time, as the consistency requirements mainly depend on the mobile application system and differ from one to another. Also forcing the mobile client to use its cache data for the purpose of reading only limits the functionality of the caching. The stateful scheme Multi-level Mobile Cache Consistency Protocol that works in client-server architecture supports different levels of consistency. The Mobile client is able to issue updates transactions, and determine the consistency requirements upon its interest. Based on the Multi-Level Mobile Cache Consistency Protocol this paper presents a framework of stateful strategy; Application Based Multi-level Mobile Cache Consistency Method (ABMMCCM) that preserves the advantages of multi-level mobile cache consistency protocol and enhances its drawbacks. In ABMMCCM the consistency requirements are designed at the server side based on the application requirements, and each data item has a single consistency requirement entry. The proposed framework is initially compared to Multi-level Mobile Cache Consistency Protocol, and it appears that ABMMCCM reduces the number of messages transfer between the base server and the mobile client, which helps in better utilizing the wireless network, and reduces the overhead from the mobile client and the base server
Seedling Parameters as affected by Soaking in Humic Acid, Salinity Stress and Grain Sorghum Genotypes
To study the effect soaking in humic acid and salinity stress on sorghum seedling parameters, a laboratory experiment accompanied in Seed Science Laboratory Faculty of Agriculture Mansoura University from June 2017 to July 2017. This exploration intended to study performance of seedling parameters of five grain sorghum cultivars viz. Dorado, hybrid 306, Giza 15, Mecca hybrid and H-305 to soaking in humic acid under salinity concentrations of 3, 6, 9, 12 and 15 dS/m-1beside the control, and humic acid soaking. The results showed that seed soaking in humic acid recorded the tallest shoot and root, weight of fresh shoot and root, weight of dry shoot and the lowest percentages of relative dry weight and highest salinity tolerance index. Seed soaking in humic acid exceeded shoot and root length (cm), weight of fresh shoot and root, weight of dry shoot and tolerance index by 14.3, 92.6, 8.7, 4.5, 4.7 and 40.8%, respectively compared without soakingin humic acid.The tallest shoot and the fresh shoot weight were produced from germinating Giza 15 cultivar. In addition, the tallest roots and highest values of stress tolerance index were recorded from sown Mecca hybrid and Giza 15 cultivars without significant differences. It could be stated that sown Mecca hybrid surpassed H-305 cultivar in root length by 36.3 %. Moreover, Giza 15 cultivar surpassed H-305 in shoot length, shoot fresh weight and stress tolerance index by 30.6, 10.1 and 29.1 %, respectively. The results clearly revealed that accumulative salinity concentrations from 3, 6, 9, 12 and 15 dSm-1 significantly produced the shortest shoot, root, weight of fresh shoot, root, weight of dry shoot, and root, highest percentages of seedling height reduction, and stress tolerance index, except the percentage of relative dry weight increased with salinity levels increased. The shortest shoot and root (cm), were recorded from the highest salinity concentrations of 15 dSm-1. The gradually increases in salinity till of 15 dSm-1 significantly diminished the length of shoot and root, the fresh weight of shoot and root, the dry weight of shoot and root, seedling height reduction percentages, and stress tolerance index by 51.7, 17.7,4.7, 59.5, 38.7 and 57.4, respectively compared the control treatment. Accordingly, sown Mecca hybrid or Giza 15 cultivar with soaking in humic acid under salinity of 6 dSm-1maximized seedling parameters and could recommended to cultivated in saline new reclaimed soils
ABMMCCS: Application based multi-level mobile cache consistency scheme
Maintaining cache consistency in mobile computing
system is a critical issue due to the inheritance limitations in mobile environment such as limited network bandwidth and mobile device energy power.Most of the existing schemes maintaining mobile cache consistency support only one level of consistency that is either strict or weak which is not suitable all the time, as various mobile applications systems have different consistency requirements on their data.Also majority of the schemes restrict the using of cached data for reading only which is limits the functionality of the caching system.In this paper, a new scheme is proposed to maintain the mobile cache consistency in a single cell wireless network called Application Based Multi-Level Mobile Cache
Consistency Scheme (ABMMCCS).The main idea in ABMMCCS is to be suitable to various real mobile application systems, by supporting multiple
levels of consistency based on the application requirements, while savingthe mobile client energy power and reducing the consumption of the
network bandwidth.The initial evaluation results show that, ABMMCCM reduces the number of uplink messages issued from the mobile client, which is assist in saving the mobile client energy and better utilizing the limited network bandwidth
A Spectral Method for Elliptic Equations: The Neumann Problem
Let be an open, simply connected, and bounded region in
, , and assume its boundary is smooth.
Consider solving an elliptic partial differential equation over with a Neumann boundary condition. The problem is converted
to an equivalent elliptic problem over the unit ball , and then a spectral
Galerkin method is used to create a convergent sequence of multivariate
polynomials of degree that is convergent to . The
transformation from to requires a special analytical calculation
for its implementation. With sufficiently smooth problem parameters, the method
is shown to be rapidly convergent. For
and assuming is a boundary, the convergence of
to zero is faster than any power of .
Numerical examples in and show experimentally
an exponential rate of convergence.Comment: 23 pages, 11 figure
- …
