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1.
Many kinds of information are hidden in email data, such as the information being exchanged, the time of exchange, and the user IDs participating in the exchange. Analyzing the email data can reveal valuable information about the social networks of a single user or multiple users, the topics being discussed, and so on. In this paper, we describe a novel approach for temporally analyzing the communication patterns embedded in email data based on time series segmentation. The approach computes egocentric communication patterns of a single user, as well as sociocentric communication patterns involving multiple users. Time series segmentation is used to uncover patterns that may span multiple time points and to study how these patterns change over time. To find egocentric patterns, the email communication of a user is represented as an item-set time series. An optimal segmentation of the item-set time series is constructed, from which patterns are extracted. To find sociocentric patterns, the email data is represented as an item-setgroup time series. Patterns involving multiple users are then extracted from an optimal segmentation of the item-setgroup time series. The proposed approach is applied to the Enron email data set, which produced very promising results.  相似文献   
2.
A simple analytical method is presented that can be used to predict the intralaminar fracture toughness of multilayered composite laminate based on the failure stresses of its sub laminates. MCCI approach is followed to verify the fracture toughness of a base laminate and the method is validated comparing the available test data on the toughness value of the base laminate with the prediction. It is observed that a better representation of carbon —epoxy base laminate by its sub laminate gives very good agreement in prediction within 3%.  相似文献   
3.
Julie Chandra  C. S.  Bipinbal  P. K.  Dileep  P.  Sasi  Sreesha  Raman  Vidya  Bindu Sharmila  T. K.  Narayanankutty  Sunil K. 《SILICON》2022,14(13):7919-7932
Silicon - Nanosilica was synthesized from a low cost raw material, olivine by a more sustainable and cost effective method. The pure nanosilica obtained was amorphous in nature with a surface area...  相似文献   
4.
The third-order optical nonlinearity of the composite film of coordination complex [CoLPPh3Cl] (L = N-(2-pyridyl)-N′-(salicylidene)hydrazine) and PMMA has been investigated by using Differential Optical Kerr Gate (DOKG) and Z-scan measurements. Large value of the third-order nonlinear optical susceptibility (χ(3)) of the order of 10?10 esu was measured and its nonlinear response time was found to be faster than or comparable to the laser pulse width (90 fs) used. The single beam Z-scan technique was used to investigate the nonlinear absorption property of the composite near 800 nm. The sample exhibit saturable absorption. The nonlinear absorption coefficient of sample is found to be ?32 cm/GW.  相似文献   
5.
Maleic anhydride was chemically attached to depolymerized natural rubber by a photochemical reaction. The product Carboxy Terminated Liquid Natural Rubber (CTNR) was characterized by 1H‐NMR, IR, GPC, and TGA. The efficiency and permanence of CTNR were compared with conventional plasticizers in NBR vulcanizates. This polymeric plasticizer was found to be less volatile and more resistant to oil extraction. The vulcanizates showed improved aging resistance compared to vulcanizates containing conventional plasticizers. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 261–267, 2002; DOI 10.1002/app.10322  相似文献   
6.
An economic model of maintenance planning for a machine shop is developed. Maintenance can be performed on an individual machine or the entire group of machines simultaneously. The coordinated maintenance on the group would save on the fixed costs associated with separate overhauls. The frequencies of maintenance on each machine within two consecutive coordinated overhauls and the time between these coordinated overhauls is determined. The resulting model selects a solution that is close to the minimum of the total cost of production and maintenance.  相似文献   
7.
An example of how simulation is used in analyzing a material handling system is presented. The Monte Carlo simulation of the Olinkraft plant not only provides the information on the effect of expansion on existing conveyer facilities, but also suggests the ways to improve the existing mode of operation. Validity of simulation is obtained by following the visual displays of the workings of different parts of the system within the simulation.  相似文献   
8.
Dileep K. Jain  Jean Claude Mora 《Energy》1992,17(12):1249-1254
Large kraft paper industries could economically generate 40% more electricity than the present demand by using steam-turbine cogeneration technology. A computer-based model has been used for the economic analysis. A systems approach, referred to as rational-use-of-energy, is proposed to overcome barriers to cogeneration.  相似文献   
9.
Mechanical properties of Nicalon-fiber-reinforced silicon carbide matrix composites were evaluated, in flexure, at various temperatures ranging from ambient to 1300°C. First matrix cracking stress ranged from 250 to 280 MPa and was relatively insensitive to test temperature. The measured ultimate strength showed a small increase from a room-temperature value of 370 to 460 MPa at 800°C. Beyond 800°C, however, strength dropped to as low as 280 MPa at 1300°C. This decrease in ultimate strength at elevated temperatures is believed to be partly due to degradation of in situ Nicalon fiber strength. Scanning electron microscopy was employed to evaluate the in situ Nicalon fiber strengths via fracture mirror size measurements. Degradation of Nicalon fiber strength is attributed to thermal damage and to structural changes to the fiber at elevated temperatures. Measured values of ultimate strength of the composites were compared with predictions made on the basis of in situ fiber strength characteristics and an available analytical model.  相似文献   
10.
Biochemical and functional properties of proteins from turkey breast meat with different ultimate pH at 24 h post-mortem (pH24) in fresh and frozen conditions have been studied. Meat with different pH24 was referred to as low, normal and high pH meat. Low and normal pH meat showed similar properties indicating their similarity in the extent of protein denaturation. Total (193 mg/g) and sarcoplasmic (99 mg/g) protein solubilities were significantly (< 0.0001) higher in high pH meat compared to those of low and normal pH meat, and hence expected to have better functional properties. Freezing caused denaturation and oxidation of proteins as revealed by a significant decrease in Ca2+-ATPase activity (< 0.0001), total protein solubility (< 0.0001), reactive (< 0.05) and total sulphydryl groups (< 0.0001) and an increase in the formation of carbonyl groups (< 0.0001), which may have implications for functionality.  相似文献   
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