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1.
This paper presents an energy-efficient switching scheme for successive approximation register (SAR) analogue-to-digital converter (ADC). The proposed scheme employs charge recycling method to keep the capacitor arrays free of transitional energy between bit generations except reset phase. In comparison with the conventional switching scheme, the proposed one achieves 100% transitional energy saving without considering reset phase. In addition, configuration of a 10-bit SAR ADC shows that the proposed switching scheme reduces the capacitor area by 25% compared with the conventional switching scheme.  相似文献   
2.
We report diffusion rates and equilibrium concentrations of water in a polyelectrolyte SPEES/PES film using ATR/FTIR spectroscopy. The data for water obtained by fitting spectral intensities to a dual mode diffusion model in the presence of different counter ions (at 0.2 mol dm−3) follow the order Li+>Cs+>Na+>Ca2+>K+. Diffusion is progressively slower for higher concentrations of NaCl (0.2-0.85 mol dm−3) and the NO3 counter anion leads to a faster diffusion rate than for Cl at the same concentration. Both water uptake and diffusion rates are broadly consistent with expectations based on the differential degrees of swelling, caused by changes in the SO3/SO3 interpolymer chain repulsive forces leading to a decrease in volume diffusion compared with the value for pure water. Direct spectral measurements of the degree of swelling confirm that the process does occur, although the order of the swelling amounts does not map directly onto that of the diffusion rates. This is probably because the interfacial dissociation processes are hydration dependent.  相似文献   
3.
Activation of K-ras gene by point mutations, a common finding in lung adenocarcinomas, has been suggested to decrease patient survival. We investigated 109 lung adenocarcinomas, mostly small, peripheral, stage I tumours (81/109) for presence of K-ras gene mutations at codons 12 and 13. Mutations were detected by denaturing gradient gel electrophoresis analysis of specific sequences amplified by polymerase chain reaction from DNA extracted from archival pathological material. Thirty-three of 109 (30.3%) tumours showed mutations at codon 12 (28/33, 84.8%) or 13 (5/33, 15.2%) of the gene. Mutations and type of nucleotide substitutions were differently distributed among cytological subtypes, being more prevalent among less differentiated (G2 and G3) tumours and among bronchial than bronchiolo-alveolar type adenocarcinomas. Survival analysis showed an adverse effect of K-ras mutation on survival, restricted to stage I tumours. Median survival for 81 stage I patients was 30 months for non-mutated tumours versus 20 months for mutated tumours (p = 0.016). Multivariate analysis showed that age of patient (p = 0.001) and K-ras mutation status (p = 0.04) were the only independent factors influencing survival significantly. These data strengthen the hypothesis that K-ras gene mutations may be useful in identifying a subgroup of patients with poor outcome.  相似文献   
4.
Neural Computing and Applications - Security is one of the primary concerns when designing wireless networks. Along detecting user identity, it is also important to detect the devices at the...  相似文献   
5.
Journal of Porous Materials - The present study aims to investigate the effects of iron (hydr)oxide phases formed during precipitation and the addition of different binders on the mechanical and...  相似文献   
6.
Extant research has focused on monitoring the behaviour of people who use mobile banking (MB) but it has paid little attention to understanding the impact of information technology usage behaviour due to cultural differences. Humans are the weakest link in information technology adoption; past research has shown that not all users are predisposed to change their behaviour radically and adopt new channels of banking. This paper examines the demographic patterns of users and non-users of MB. The paper also investigates the attitudinal influences of users and non-users of MB based on innovation attributes. Using empirical research, the study identifies constructs of innovation attributes that were perceived to be significantly different among the users and non-users of MB. The study provides valuable insights into MB in Saudi Arabia that have not been previously investigated. From a practical point, findings of this study will be particularly useful to banks, financial institutions and telecommunication service providers.  相似文献   
7.
Therapeutic vaccines are being developed as a promising new approach to treatment for cancer patients. There are still many unanswered questions about which kind of therapeutic vaccines are the best for the cancer treatments? In this paper we consider a mathematical model, in the form of a system of ordinary differential equations (ODE), this system is an example from a class of mathematical models for immunotherapy of the tumor that were derived from a biologically validated model by Lisette G. de Pillis. The problem how to schedule a variable amount of which vaccines to achieve a maximum reduction in the primary cancer volume is consider as an optimal control problem and it is shown that optimal control is quadratic with 0 denoting a trajectory corresponding to no treatment and 1 a trajectory with treatment at maximum dose along that all therapeutics are being exhausted. The ODE system dynamics characterized by locating equilibrium points and stability properties are determined by using appropriate Lyapunov functions. Especially we attend a parametric sensitivity analysis, which indicates the dependency of the optimal solution with respect to disturbances in model parameters.  相似文献   
8.

Software product prone to continuous evolution due to increase in the use of technology. Therefore, more stakeholders are involved in software evolution increases the cost and complexity. This required optimization of resources and cost to handle evolution with Global Software Development (GSD) to utilize time zones efficiently. The significance challenge of GSD reports: time zone difference, geographical location, communication delays, knowledge sharing, control among stakeholders and development team. Because of these challenges, the requirements for development in GSD environment are also challenge as compared to on site development. Different requirement engineering methods have been used to improve the requirements analysis to deal with ambiguities and inconsistency in large set of requirements. The customization and tailoring of requirements according to changing project’s situations required to improve project development with reusing existing agile methods during requirement engineering phase. Moreover, complex information systems where heterogeneity is inevitable that implies the involvement of divergent stakeholders and necessitate a comprehensive framework to capture multidimensional viewpoints and fulfill aforementioned issues. Therefore, a situational multi-dimensional agile requirement engineering method has been proposed to support team and stakeholders’ viewpoints. The schema of the proposed method is based on challenges recognized by performing Literature Review. Then proposed method has been evaluated via experimental approach and statistical analysis conducted to validated reliability of data collected. This result is significant approved both practically and statistically that the proposed approach ease to use, implement, trained and increased productivity and performance. Hence, the experimental study for the evaluation of the proposed approach results concluded that, proposed approach is the important multimedia tool for supporting organization and distributed development team for information sharing, collaboration, product development.

  相似文献   
9.
Journal of Central South University - This work is concerned with the analysis of blood flow through inclined catheterized arteries having a balloon (angioplasty) with time-variant overlapping...  相似文献   
10.
Since chromatographic separation is a dynamic process, with the interactions between the drug and the chiral stationary phase mediated by the solvent, no single interacting structure, such as could be found by minimizing the energy, could possibly describe and account for the ratio of residence times in the chromatographic column for the enantiomeric pair. We describe the use of explicit-solvent fully atomistic molecular dynamics simulations, permitting all the interactions between the atoms constituting the chiral stationary phase, solvent molecules and the drug molecule. This allows us to better understand the molecular dynamic chiral recognition that provides the discrimination, which results in the separation of enantiomers by high performance liquid chromatography. It also provides a means of predicting, for a given set of conditions, which enantiomer elutes first and an estimate of the expected separation factor. In this review, we consider the use of molecular dynamics toward this understanding and prediction.  相似文献   
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