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Mobile applications have grown rapidly in size. This dramatic increases in size and complexity make mobile applications less accessible to a broader scope of users. The prevailing approach for better accessibility of mobile applications is to manually reimplement slimmed versions with a small but representative portion of a regular original app. Unfortunately, this approach imposes significant burden on developers. We propose a system called Madusa to enable developers to effectively customize and reduce their mobile applications for Android. Madusa takes as input an original app, an upper bound on the size of a reduced version, and usage scenarios as a high-level specification of its desired core functionality. The output is a reduced version of the app that is still correct with respect to the specification while not exceeding the size limit. Madusa constructs a graph representing dependencies among methods and resources and identifies a sub-part of the graph using integer linear programming to generate a reduced version that exhibits behaviors as similar as possible to the original app. Our experimental evaluation on a suite of 19 Android apps available on Google Play Store. Madusa effectively converges to the desired simplified apps by reducing the app size by 40% on average (maximally by 60%). We conclude our approach effectively removes redundant code and resources with respect to given usage scenarios.

The purpose of this study was to evaluate the radiographic and clinical outcomes of patients with hallux valgus (HV) with concomitant metatarsus adductus (MA) treated with distal chevron metatarsal osteotomy (DCMO), without any procedure for the second or third metatarsal.A multicentre retrospective study involving four hospitals was conducted. A total of 45 feet from 38 patients who had received DCMO for HV with MA with at least one year post-operative follow-up were analysed. HV angle (HVâ), inter-metatarsal angle (IMâ), MA angle (MAâ), and the lateral sesamoid grade were measured. Foot function index (FFI) and visual analogue scale (VAS) were recorded. Patients were divided into mild (18° ≤ MAâ 20°) and moderate (20° ≤ MAâ) MA groups, and results were compared.The mean HVâ and IMâ improved significantly from 35.1° and 14.4° pre-operatively to 10.6° and 7.1° one year post-operatively (p 0.001). There were no differences in pre-operative HVâ, IMâ, or the sesamoid grade, and also no difference in post-operative HVâ or the sesamoid grade between mild and moderate MA groups. Only the mean post-operative IMâ showed a difference between the two groups (8.3° vs. 6.3°; p = 0.019). All clauses of FFI and VAS improved significantly (p 0.001). When the extent of improvement was compared between the two groups, there were no significant differences in any category (p 0.05). The total rate of recurrence (HVâ ≥ 20°) was 11.1% (5/45), and although the moderate group (4/29, 13.8%) had a higher proportion than the mild group (1/16, 6.3%), this was not statistically significant (p = 0.641).DCMO for patients with HV with MA had satisfactory radiographic and clinical outcomes with minimal recurrence. Except in cases of severe combined deformity, we recommend performing DCMO alone without any additional procedure or manipulation of the other metatarsals as a viable treatment option.

We evaluated the clinical and radiological outcomes of patients following total hip arthroplasty (THA) for acetabular fracture. This was a retrospective cohort study in a single center. The medical records of patients who underwent THA from March 2002 to March 2017 were reviewed. Inclusion criteria were THA and a history of open reduction and internal fixation of acetabular fractures. Thirty-seven patients with a mean age of 56.2 years were enrolled. The Harris hip score (HHS), acetabular fracture classification, time interval between acetabular fracture and THA, cause of THA, surgical approach, implant type, complications, radiographic results, and Kaplan–Meier survival curves were analyzed. All patients were followed up for an average of 6.6 years. The mean preoperative HHS of 42.5 had improved to 83.5 at the final follow-up (p

Gas hydrates consist of guest gas molecules inside hydrogen-bonded water lattices. Natural gas hydrates are found in offshore and permafrost regions. The large amounts of gas hydrate reserves suggest the potential of gas hydrates as an energy resource if economically viable production methods were developed. The proper understandings of hydrate formation/dissociation are important for the drilling and oil production applications. The investigations of physical and geotechnical properties provide the in-depth understandings of the in-situ hydrate formation mechanism and the associated production technologies. The purpose of this review paper is to provide a starting kit for civil engineers who have recently started the research related to the hydrate development and production and want to have insights on the general trends of the hydrate research and the relevant knowledge needed for their research. Gas hydrate explorations include the geophysical explorations, such as the seismic survey, the borehole logging and the geological and geochemical explorations. Gas hydrate productions require the dissociation of gas hydrates, and the production technologies are categorized based on the dissociation techniques involved: depressurization method, thermal stimulation method, and inhibitor injection method. Establishing safe and efficient gas production technology requires the extensive information on the geotechnical characteristics of hydrate reservoirs. Flow assurances, the integrity of sediment formation and the well bore stability are crucial for the safe and efficient productions of gases from gas hydrates in sediments. The strength and deformation characteristics, the fluid migration characteristics, and the thermal conduction characteristics are key factors for controlling the above.

Standard unsupervised linear feature extraction methods find orthonormal (PCA) or statistically independent (ICA) latent variables that are good for data representation. These representative features may not be optimal for the classification tasks, thus requiring a search of linear projections that can give a good discriminative model. A semi-supervised linear feature extraction method, namely dICA, had recently been proposed which jointly maximizes the Fisher linear discriminant (FLD) and negentropy of the extracted features [Dhir and Lee in Discriminant independent component analysis. In: Proceedings of the international conference intelligent data engineering and automated learning, LNCS 5788:219–225 (Full paper is submitted to IEEE Trans. NN) 2009]. Motivated by the independence and unit covariance of the extracted dICA features, maximizing the determinant of between-class scatter of the features matrix is theoretically the same as the maximization of FLD. This also reduces the computational complexity of the algorithm. In this paper, we concentrate on text databases that follow inherent exponential distribution. Approximation and the maximization of negentropy for data with asymmetric distribution is discussed. Experiments on the text categorization problem show improvements in classification performance and data reconstruction.

Au-coated vertical silicon nanowire electrode array (VSNEA) was fabricated using a combination of bottom-up and top-down approaches by chemical vapor deposition and complementary metal-oxide-semiconductor process for biomolecule sensing. To verify the feasibility for the detection of biomolecules, Au-coated VSNEA was functionalized using peptides having a fluorescent probe. Cyclic voltammograms of the peptide-functionalized Au-coated VSNEA show a steady-state electrochemical current behavior. Because of the critically small dimension and vertically aligned nature of VSNEA, the current density of Au-coated VSNEA was dramatically higher than that of Au film electrodes. Au-coated VSNEA further showed a large current difference with and without peptides that was nine times more than that of Au film electrodes. These results indicate that Au-coated VSENA is highly effective device to detect peptides compared to conventional thin-film electrodes. Au-coated VSNEA can also be used as a divergent biosensor platform in many applications.

This study introduces optical properties of a columnar structured zinc oxide [ZnO] antireflection coating for solar cells. We obtained ZnO films of columnar structure on glass substrates using a specially designed radio frequency magnetron sputtering system with different growth angles. Field-emission scanning electron microscopy was utilized to check the growth angles of the ZnO films which were controlled at 0°, 15°, and 30°. The film thickness was fixed at 100 nm to get a constant experiment condition. Grain sizes of the ZnO films were measured by X-ray diffraction. A UV-visible spectrometer was used to measure the transmittance and reflectance of the ZnO film columnar structures as a function of the growth angles.

In this paper, we describe a method of amorphous silicon carbide film formation for a solar cell passivation layer. The film was deposited on p-type silicon (100) and glass substrates by an RF magnetron co-sputtering system using a Si target and a C target at a room-temperature condition. Several different SiC [Si1-xCx] film compositions were achieved by controlling the Si target power with a fixed C target power at 150 W. Then, structural, optical, and electrical properties of the Si1-xCx films were studied. The structural properties were investigated by transmission electron microscopy and secondary ion mass spectrometry. The optical properties were achieved by UV-visible spectroscopy and ellipsometry. The performance of Si1-xCx passivation was explored by carrier lifetime measurement.