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101.
The key threat to information security comes from employees who do not comply with information security policies. We developed a new multi-theory based model that explained employees’ adherence to security policies. The paradigm combines elements from the Protection Motivation Theory, the Theory of Reasoned Action, and the Cognitive Evaluation Theory. We validated the model by using a sample of 669 responses from four corporations in Finland. The SEM-based results showed that perceived severity of potential information security threats, employees’ belief as to whether they can apply and adhere to information security policies, perceived vulnerability to potential security threats, employees’ attitude toward complying with information security policies, and social norms toward complying with these policies had a significant and positive effect on the employees’ intention to comply with information security policies. Intention to comply with information security policies also had a significant impact on actual compliance with these policies. High level managers must warn employees of the importance of information security and why it is necessary to carry out these policies. In addition, employees should be provided with security education and hands on training. 相似文献
102.
Carrier aggregation (CA) technique has been adopted by 3GPP LTE-Advanced due to its ability of enhancing the spectrum efficiency and peak data rates through aggregating multiple component carriers (CCs). Two main factors make power control optimization very essential for CA-MIMO radio link: the different channel characteristics in multiple CCs, and multiple power constraint conditions (per-CC, per-antenna and pertransmitter power constraints) in the actual CA system deployment. This paper firstly derives the degenerate conditions of optimal power allocation for a single-transmitter CA-MIMO system. Stemming from the derived degenerate conditions, we propose a modified hybrid gradient optimal power allocation(MHGOPA) algorithm to maximize the system performance. Simulation results verify the validity of the proposed resource allocation approach by comparing with baseline average power allocation algorithm. Finally, we extend the MHGOPA algorithm into a heterogeneous CA network with multiple transmitters working simultaneously. 相似文献
103.
Mikko Huttunen 《Journal of materials science. Materials in medicine》2013,24(5):1131-1144
This study focuses on analyzing the effects of several factors on the rate of decay of inherent viscosity (iv) during hydrolytic degradation. The analysis was made for oriented PLLA, 96L/4D PLA and 80L/20D,L PLA. The analyzed polymers were found to have identical rate of iv loss (P < 0.05), given that the materials have otherwise similar initial material properties. The effect of the post-processing residual monomer was dose dependent, i.e. the higher the monomer content the faster the degradation (P < 0.05). Samples with a smaller diameter (1.1 mm) were found to have a faster rate of iv loss than the samples with a larger diameter (4 mm) (P < 0.05). A multiple linear regression analysis was used to create a five-component linear model to predict changes in the materials’ inherent viscosity. This model yielded accurate predictions during the initial stages of the hydrolytic degradation process where the iv loss was virtually linear. 相似文献
104.
Diblock copolymers based on polystyrene (PS) macroinitiators and four different fluorinated monomers (perfluorooctyl ethyl methacrylate (FMA), pentafluorostyrene (FS), perfluorooctyl-ethylene oxymethyl styrene (EMS), 2,3,5,6-tetrafluoro-4-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecaoxy)styrene (FSF)) were synthesized via atom transfer radical polymerization (ATRP). The lengths of the PS and fluorinated blocks were altered and the surface and self-assembling properties of the polymers were compared with respect to the fluorinated monomer used and the fluorine content. The surface properties, contact angles and surface tension, were enhanced by the existence of the CF3 groups at the end of the alkyl chains compared with poly(pentafluorostyrene). Hydrophobicity of the surfaces was further enhanced by electrospinning the polymer solutions, which yielded superhydrophobic surfaces with water contact angles >150° for polymers having CF3 groups. 相似文献
105.
Nikolaos Nikolaou Panagiotis Dimitrakis Pascal Normand Vassilios Ioannou-Sougleridis Konstantinos Giannakopoulos Konstantina Mergia Kaupo Kukli Jaakko Niinistö Mikko Ritala Markku Leskelä 《Solid-state electronics》2012
In this work we report the performance of the SiO2/Si3N4/HfO2 and SiO2/Si3N4/ZrO2 stacks with emphasis on the influence of atomic layer deposition chemistry used for forming the HfO2 and ZrO2 blocking layers. Two Hf precursors were employed – tetrakis(ethylmethylamino)hafnium (TEMAH) and bis(methylcyclopentadienyl)methoxymethyl hafnium (HfD-04). For ZrO2, tetrakis(ethylmethylamino)zirconium (TEMAZ) and bis(methylcyclopentadienyl)methoxymethyl zirconium (ZrD-04) were used as metal precursors. Ozone was used as the oxygen source. The structural characteristics of the stacks were examined by transmission electron microscopy and grazing incidence X-ray diffraction. The electrical properties of the stacks were studied using platinum-gated capacitor structures. The memory performance of the stacks was evaluated by write/erase (W/E) measurements, endurance and retention testing. Endurance measurements revealed the most important difference between the stacks. The films grown from TEMAH and TEMAZ could withstand a significantly higher number of W/E pulses (>3 × 105 in the 10 V/?11 V, 10 ms regime), in comparison to the stacks made from HfD-04 and ZrD-04 precursors (<5 × 103 W/E cycles). This difference in endurance characteristics is attributed mainly to the different deposition temperatures suited for these two precursors and the nature of the layer formed at the Si3N4/HfO2 and the Si3N4/ZrO2 interfaces. 相似文献
106.
Marika P. Immonen Mikko Karppinen Jorma K. Kivilahti 《Microelectronics Reliability》2007,47(2-3):363-371
In this paper, the effects of environmental stresses on the properties of polymeric optical waveguides were investigated. Optical multimode waveguides were embedded on printed circuit boards by employing commercial polymers. Three optical-PCB constructions varying in board structure and in optical build-up materials were compared. The guide systems were subjected to four different tests: damp heat-high humidity, isothermal annealing, thermal shock and environmental flowing multigas test. Isothermal annealing reduced the refractive index to greatest extent. The optical-PCB structure with optical surface build-up layer was observed to be more vulnerable under temperature shock when compared with the O-PCB with optical inner layer. The buffer layer beneath the optical build-up was found to improve the stability of the optical waveguides significantly. The results indicated of a wavelength dependence to the aging factor with a failure mechanism. The factors affecting the performance and reliability of polymer-based optical waveguides on PCBs were discussed. 相似文献
107.
Friction coefficients for cubic boron nitride were determined with the use of hybrid density functional B3LYP calculations.
Two cluster models and an infinite periodic model were applied. Various contacts between duplicated surfaces and different
sliding paths of the surfaces with respect to each other were taken into consideration, and friction coefficients were derived.
The calculations suggest that three different sliding paths contribute to the friction, the friction coefficient for the periodic
model being 0.21 at its lowest. This value is in agreement with previous experimental studies, where a friction coefficient
of 0.1–0.2 has been measured for cubic boron nitride. 相似文献
108.
Jani Korhonen Timo Ojala Annu Ristola Manne Kesti Vesa Kilpelänaho Mikko Koskinen Eveliina Viippola 《Personal and Ubiquitous Computing》2007,11(7):577-589
This paper describes the Mobile Fair Diary (MFD), which is designed to allow a housing fair customer to make a personalized
digital recording of his/her visit to a hectic fairground for later use. The MFD is a hybrid interface service comprising
of an application for a camera equipped smart phone and a website accessed by a PC. The smart phone application is used for
taking context-aware notes such as visual codes, photos, dictations and text. The notes are uploaded onto a website, where
they can be viewed with a PC in a contextually ordered view for browsing, organizing and sharing. The MFD was empirically
evaluated in a real-life environment of use with genuine end users by a large-scale field trial at a national housing fair.
The results testify to the very successful design of the MFD with high usefulness. 相似文献
109.
Frederick K. Teye Mikko Hautala Matti Pastell Jaan Praks Imbi Veermäe Väino Poikalainen Aime Pajumägi Tapani Kivinen Jukka Ahokas 《Energy and Buildings》2008,40(7):1194-1201
A series of ventilation, thermal and indoor air quality measurements were performed in 14 different dairy buildings in Estonia and Finland. The number of animals in the buildings varied from 30 to 600. Measurements were made all year round with ambient temperatures ranging between −40 °C and +30 °C. The results showed that microclimatic conditions in the dairy buildings were affected by the design of the building, outside temperature, wind, ventilation and manure handling method. The average inside air concentration of carbon dioxide was 950 ppm, ammonia 5 ppm, methane 48 ppm, relative humidity 70% and inside air velocity was 0.2 m/s. Although occasionally exceeded, the ventilation and average indoor air quality in the dairy buildings were mainly within the recommended limits. 相似文献
110.
Modelling the spatial distribution of a threatened butterfly: Impacts of scale and statistical technique 总被引:2,自引:0,他引:2
Risto K. Heikkinen Miska Luoto Mikko Kuussaari Tuuli Toivonen 《Landscape and urban planning》2007,79(3-4):347-357
This paper compares the performance of five modelling methods in the prediction of a species distribution, using a data set describing the distribution of the threatened clouded apollo butterfly (Parnassius mnemosyne) in south-west Finland. The five statistical techniques included were: generalized linear models (GLM), generalized additive models (GAM), classification tree analysis (CTA), neural networks (ANN) and multiple adaptive regression splines (MARS). The accuracy of the models was examined at three spatial resolutions (1, 25 and 100 ha) by area under the curve (AUC) and kappa statistics. All five modelling techniques had a relatively high discrimination capacity for the occurrence of clouded apollo. Classification tree analysis provided the least robust model performance. The differences between the other methods were small, although GAM and MARS provided marginally the best stability and performance. The most accurate models were developed for the resolutions of 1 ha (highest AUC values) and 25 ha (highest kappa values) and the least accurate models for the resolution of 100 ha. Our work shows that modern modelling techniques can provide useful forecasts of species distributions in unsurveyed parts of landscapes and provide valuable contributions to conservation and management planning. However, the success of applying the new modelling tools can be influenced by the choice of statistical technique and especially of spatial resolution. In conclusion, small changes in the spatial scale may result in a clear decrease in the model performance and thus caution should be exercised when implementing the models and their predictions in practice. 相似文献