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排序方式: 共有640条查询结果,搜索用时 15 毫秒
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Mobile software applications have to cope with a particular environment that involves small size, limited resources, high autonomy requirements, competitive business models and many other challenges. To provide development guidelines that respond to these needs, several practices have been introduced; however, it is not clear how these guidelines may contribute to solve the issues present in the mobile domain. Furthermore, the rapid evolution of the mobile ecosystem challenges many of the premises upon which the proposed practices were designed. In this paper, we present a survey of the literature on software assurance practices for mobile applications, with the objective of describing them and assessing their contribution and success. We identified, organized and reviewed a body of research that spans in three levels: software development processes, software product assurance practices, and software implementation practices. By carrying out this literature survey, we reviewed the different approaches that researchers on Software Engineering have provided to address the needs that raise in the mobile software development arena. Moreover, we review the evolution of these practices, identifying how the constant changes and modernization of the mobile execution environment has impacted the methods proposed in the literature. Finally, we introduced discussion on the application of these practices in a real productive setting, opening an area for further research that may determine if practitioners have followed the proposed assurance paradigms. 相似文献
3.
L Giorgi A Di Filippo A Franchini L Rizzo S Benvenuti M Conti GP Novelli 《Canadian Metallurgical Quarterly》1994,60(1-2):43-47
OBJECTIVE: The reflex response to orotracheal intubation provokes an increase of arterial pressure accompanied by an increase of chorioides volume and a consequent ocular hypertone. There are several methods to reduce the reflex response due to intubation. One of the most effective is topical anaesthesia of larynx and trachea. Experiments were directed to evaluate the efficacy of topical anaesthesia to reduce the intraocular hypertone due to orotracheal intubation. DESIGN: A prospective randomized mask study was conduct on patients undergoing ophthalmologic (anterior segment) surgery at the Eye Clinic of Florence University. METHODS: Intraocular pressure was measured by a Goldman tonometer at four times: T0 = basal, T1 = 2' minutes after induction of general anaesthesia, T2 = 2' minutes after laryngoscopy, T3 = 2' minutes after orotracheal intubation. At the same moments, systolic blood pressure, heart rate, rate pressure pro duct were measured. Patients were randomly divided in two groups: Group L (n = 10) in which was evaluated the efficacy of laryngotracheal topical spray of lidocaine 4% (2 ml) and Group F (n = 10) in which saline was used instead of anesthetic. The filling of the LTA kit (Abbott) was made by a person not involved in the experiments. DATA ANALYSIS: Student's t test for unpaired data. RESULTS: Topical anaesthesia reduces the increase of intraocular pressure, hypertension and rate pressure product due to intubation. The intraocular pressure reduces to 13% less than basal value in Group L and increase to 50% more than basal value in Group F. CONCLUSION: The topical anaesthesia of larynx and trachea is effective to reduce the intraocular hypertension due to the reflex response evoked by orotracheal intubation. 相似文献
4.
R Zanardi L Franchini M Gasperini E Smeraldi J Perez 《Canadian Metallurgical Quarterly》1997,12(4):195-197
The aim of this open pilot study was to evaluate the efficacy of fluvoxamine in the continuation as well as in the maintenance therapy of delusional depression. Thirty patients with recurrent, unipolar depression (DSM-IV criteria) were selected who had at least one depressive episode during the 18 months preceding the delusional depressive index episode and were treated with fluvoxamine 300 mg/day. Twenty-five of them had a sustained response to this short-term treatment and agreed to enter into the 30-month follow up study. All participants completed the follow up period. No relapse was observed during the 6 months of continuation therapy. During the further 24 months of maintenance therapy, 80% of the patients remained well, whereas 20% (five out of 25) had a single recurrence. Based on these observations, fluvoxamine might be a promising drug for long-term therapy of delusional depression. Further controlled studies are required to confirm this finding. 相似文献
5.
Prof. Alessia Carocci Dr. Mariagrazia Roselli Prof. Roberta Budriesi Dr. Matteo Micucci Prof. Jean-François Desaphy Dr. Concetta Altamura Dr. Maria Maddalena Cavalluzzi Dr. Maddalena Toma Dr. Giovanna Ilaria Passeri Dr. Gualtiero Milani Dr. Angelo Lovece Prof. Alessia Catalano Dr. Claudio Bruno Dr. Annalisa De Palma Prof. Filomena Corbo Prof. Carlo Franchini Prof. Solomon Habtemariam Prof. Giovanni Lentini 《ChemMedChem》2021,16(3):578-588
Under the hypothesis that cardioprotective agents might benefit from synergism between antiarrhythmic activity and antioxidant properties, a small series of mexiletine analogues were coupled with the 2,2,5,5-tetramethylpyrroline moiety, known for its antioxidant effect, in order to obtain dual-acting drugs potentially useful in the protection of the heart against post-ischemic reperfusion injury. The pyrroline derivatives reported herein were found to be more potent as antiarrhythmic agents than mexiletine and displayed antioxidant activity. The most interesting tetramethylpyrroline congener, a tert-butyl-substituted analogue, was at least 100 times more active as an antiarrhythmic than mexiletine. 相似文献
6.
The hydrophobic-polar (HP) model has been widely studied in the field of protein structure prediction both for theoretical purposes and as a benchmark for new optimization strategies. In this work we present results of the recently proposed Hybrid Monte Carlo Ant Colony Optimization heuristic in the HP model using a fragment assembly-like strategy. Moreover we extend that method introducing a general framework for optimization in the HP model, called Local Landscape Mapping, and we test it using the pull moves set to generate solutions. We describe the heuristic and compare results obtained on well known HP instances in the 3-dimensional cubic lattice to those obtained with standard Ant Colony optimization and Simulated Annealing. Fragment assembly-like tests were performed using a modified objective function to prevent the creation of overlapping walks. Results show that our method performs better than the other heuristics in all benchmark instances when the fragment assembly-like strategy is used while in the case of pull moves-based neighborhood its performance is comparable to that of simulated annealing. 相似文献
7.
Chiara Damiani Dario Pescini Riccardo Colombo Sara Molinari Lilia Alberghina Marco Vanoni Giancarlo Mauri 《Natural computing》2014,13(3):321-331
Constraint-based modeling is largely used in computational studies of metabolism. We propose here a novel approach that aims to identify ensembles of flux distributions that comply with one or more target phenotype(s). The methodology has been tested on a small-scale model of yeast energy metabolism. The target phenotypes describe the differential pattern of ethanol production and O2 consumption observed in “Crabtree-positive” and “Crabtree-negative” yeasts in changing environment (i.e., when the upper limit of glucose uptake is varied). The ensembles were obtained either by selection among sampled flux distributions or by means of a search heuristic (genetic algorithm). The former approach provided indication about the probability to observe a given phenotype, but the resulting ensembles could not be unambiguously partitioned into “Crabtree-positive” and “Crabtree-negative” clusters. On the contrary well-separated clusters were obtained with the latter method. The cluster analysis further allowed identification of distinct groups within each target phenotype. The method may thus prove useful in characterizing the design principles underlying metabolic plasticity arising from evolving physio-pathological or developmental constraints. 相似文献
8.
Cecilia Laschi Gioel Asuni Eugenio Guglielmelli Giancarlo Teti Roland Johansson Hitoshi Konosu Zbigniew Wasik Maria Chiara Carrozza Paolo Dario 《Autonomous Robots》2008,25(1-2):85-101
This paper presents a sensory-motor coordination scheme for a robot hand-arm-head system that provides the robot with the capability to reach an object while pre-shaping the fingers to the required grasp configuration and while predicting the tactile image that will be perceived after grasping. A model for sensory-motor coordination derived from studies in humans inspired the development of this scheme. A peculiar feature of this model is the prediction of the tactile image. The implementation of the proposed scheme is based on a neuro-fuzzy module that, after a learning phase, starting from visual data, calculates the position and orientation of the hand for reaching, selects the best-suited hand configuration, and predicts the tactile feedback. The implementation of the scheme on a humanoid robot allowed experimental validation of its effectiveness in robotics and provided perspectives on applications of sensory predictions in robot motor control. 相似文献
9.
Marco Franchini 《Water Resources Management》1994,8(3):225-238
With reference to the kinematic wave theory coupled with the hypothesis of constant linear velocity for the rating curve, rising limb analytical solutions have been calculated for overland flow, over an Hortonian-infiltrating surface, and sediment discharge. These analytical solutions are certainly easier to use than the numerical integration of the basic equations and they may be used to obtain an initial evaluation of the parameters of more complex models generally devised for complicated cases.Notation
a
exponent of the Horton law [T–1]
-
b
exponent of the rill erosion equation
-
B
inter-rill erosion coefficient [ML–m–2T
m–1]
-
c
sediment concentration [ML–3]
-
c
o
reference sediment concentration [ML–3]
-
E
I
inter-rill erosion [ML–2T–1]
-
E
R
rill erosion [ML–2T–1]
-
f
c
final infiltration rate of the soil [LT–1]
-
f
o
initial infiltration rate of the soil [LT–1]
-
h
flow depth [L]
-
h
o
reference flow depth [L]
-
i
infiltration rate [LT–1]
-
k
rill erosion coefficient [ML–1–b
T–1]
-
K
integration constant
-
L()
Laplace transformation
-
m
exponent of the inter-rill erosion equation
-
n
Manning's coefficient [L–1/3T]
-
p
rainfall intensity [LT–1]
-
q
water discharge per unit width [L2T–1]
-
q
s
sediment discharge per unit width [ML–1T–1]
-
t
time [T]
-
t
p
ponding time [T]
-
x
distance along the flow direction [L]
Greek Letters
coefficient of the stage-discharge equation [L2–T–1]
-
exponent of the stage-discharge equation
-
rill erosion coefficient [L–1] 相似文献
10.
We provide a uniform framework for the study of index data structures for a two-dimensional matrixTEXT[1:n, 1:n] whose entries are drawn from an ordered alphabetΣ. An index forTEXTcan be informally seen as the two-dimensional analog of the suffix tree for a string. It allows on-line searches and statistics to be performed onTEXTby representing compactly theΘ(n3) square submatrices ofTEXTin optimalO(n2) space. We identify 4n−1families of indices forTEXT, each containing ∏ni=1 (2i−1)! isomorphic data structures. We also develop techniques leading to a single algorithm that efficiently builds any index in any family inO(n2 log n) time andO(n2) space. Such an algorithm improves in various respects the algorithms for the construction of the PAT tree and the Lsuffix tree. The framework and the algorithm easily generalize tod>2 dimensions. Moreover, as part of our algorithm, we provide new algorithmic tools that yield a space-efficient implementation of the “naming scheme” of R. Karpet al.(in“Proceedings, Fourth Symposium on Theory of Computing,” pp. 125–136) for strings and matrices. 相似文献