Erratum to: Malaria infected erythrocyte classification based on a hybrid classifier using microscopic images of thin blood smear

Multimedia Tools and Applications -     

Is cloned code really stable?

Clone has emerged as a controversial term in software engineering research and practice. The impact of clones is of great importance from software maintenance perspectives. Stability is a well investigated term in assessing the impacts of clones on software maintenance. If code clones appear to exhibit a higher instability (i.e., higher change-proneness) than non-cloned code, then we can expect that code clones require higher maintenance effort and cost than non-cloned code. A number of studies have been done on the comparative stability of cloned and non-cloned code. However, these studies could not come to a consensus. While some studies show that code clones are more stable than non-cloned code, the other studies provide empirical evidence of higher instability of code clones. The possible reasons behind these contradictory findings are that different studies investigated different aspects of stability using different clone detection tools on different subject systems using different experimental setups. Also, the subject systems were not of wide varieties. Emphasizing these issues (with several others mentioned in the motivation) we have conducted a comprehensive empirical study where we have - (i) implemented and investigated seven existing methodologies that explored different aspects of stability, (ii) used two clone detection tools (NiCad and CCFinderX) to implement each of these seven methodologies, and (iii) investigated the stability of three types (Type-1, Type-2, Type-3) of clones. Our investigation on 12 diverse subject systems covering three programming languages (Java, C, C#) with a list of 8 stability assessment metrics suggest that (i) cloned code is often more unstable (change-prone) than non-cloned code in the maintenance phase, (ii) both Type 1 and Type 3 clones appear to exhibit higher instability than Type 2 clones, (iii) clones in Java and C programming languages are more change-prone than the clones in C#, and (iv) changes to the clones in procedural programming languages seem to be more dispersed than the changes to the clones in object oriented languages. We also systematically replicated the original studies with their original settings and found mostly equivalent results as of the original studies. We believe that our findings are important for prioritizing code clones from management perspectives.     

Complementary‐based coalition formation for energy microgrids

In recent years, the notion of electrical energy microgrids (MGs), in which communities share their locally generated power, has gained increasing interest. Typically, the energy generated comes from renewable resources, which means that its availability is variable, ie, sometimes there may be energy surpluses and at other times energy deficits. This energy variability can be ameliorated by trading energy with a connected electricity grid. However, since main electricity grids are subject to faults or other outages, it can be advantageous for energy MGs to form coalitions and share their energy among themselves. In this work, we present our model for the dynamic formation of such MG coalitions. In our model, MGs form coalitions on the basis of complementary weather patterns. Our agent‐based model, which is scalable and affords autonomy among the MGs participating in the coalition (agents can join and depart from coalitions at any time), features methods to reduce overall “discomfort” so that, even when all participating MGs in a coalition experience deficits, they can share energy so that their overall discomfort is reduced. We demonstrate the efficacy of our model by showing empirical studies conducted with real energy production and consumption data.     

Mobile Network Operator and Mobile User Cooperation for Customized D2D Data Services

The explosive growth of smart devices has led to the evolution of multimedia data (mainly video) services in mobile networks. It attracted many mobile network operators (MNO) to deploy novel network architectures and develop effective economic policies. Mobile data offloading through smart devices (SDs) by exploring device-to-device (D2D) communications can significantly reduce network congestion and enhance quality of service at a lower cost, which is the key requirement of upcoming 5G networks. This reasonable cost solution is useful for attracting mobile users to participate in the offloading process by paying them proper incentives. It is beneficial for MNOs as well as mobile users. Moreover, D2D communications promise to be one of the prominent services for 5G networks. In this paper, we present a combinatorial optimal reverse auction (CORA) mechanism, which efficiently selects and utilizes available high-end SDs on the basis of available resources for offloading purposes. It also decides the optimal pricing policy for the selected SDs. The efficiency of CORA has been realized in terms of bandwidth and storage demand. Subsequently, we implement caching in SDs, eNodeB (eNB), and evolved packet core (EPC) with the help of our novel video dissemination cache update algorithm to solve the latency or delay issues in the offloading process. Due to high popularity, we specifically focus on video data. Simulation results show that the proposed SD caching scenario curtails the delay up to 75% and the combined cache (CC) scenario slashes the delay varying from 15 to 57%. We also scruitinize the video downloading time performance of various cache scenarios (i.e., CC, EPC cache, eNB cache, and SD cache scenarios).     

Half-of-the-sites reactivity of F235C {lambda}-repressor: implications for the structure of the whole repressor

A site-directed mutation, F235C, was created at the penultimateresidue of the -repressor. Measurement of dimer–monomerdissociation constant suggested that dimer–monomer dissociationof the mutant repressor is similar to that of the wild-type.Affinity towards a single operator O_R1 is also similar to thatof the wild-type repressor. The mutant repressor gene in a multi-copyplasmid confers immunity towards infection by a cI^- lambda phage,suggesting preservation of functional integrity. Far-UV circulardichroism spectra show no major change in the secondary structure.Fluorescence quenching experiments, however, suggest increasedexposure of some tryptophan residues. The urea denaturationprofile indicates decreased stability of a part of the C-terminaldomain. Under non-denaturing conditions, cysteine-235 showshalf-of-the-sites reactivity, i.e. on average only one out oftwo cysteine-235 residues in the dimer shows reactivity towardssulfhydryl reagents. Fluorescence energy transfer between randomlylabeled donor and acceptor fluorescent probes indicates thatonly one sulfhydryl per dimer is reactive, suggesting true half-of-the-sitesreactivity. The structural role of the C-terminal tail in thewhole repressor dimer is discussed.     

Solubility and agronomic effectiveness of partially acidulated phosphate rocks as influenced by their iron and aluminium oxide content

Partially acidulated phosphate rock (PAPR) has been shown to be an effective source of P for plants grown on acid soils. Less information in available, however, regarding the effect of the phosphate rock (PR) source on the solubility and agronomic effectiveness of PAPR.The effect of Fe₂O₃ + Al₂O₃ content in PR on the quality of PAPR produced was investigated in this study. Nine sources of PR from Africa, Latin America, and the United States, representing a range of Fe₂O₃ + Al₂O₃ from 0.7% to 12.4%, were used. In a single-step process, the finely ground PRs were partially acidulated with H₂SO₄ at the 30% or 50% acidulation level and granulated (–3.35 + 1.18 mm or –6 + 14 mesh). It was found that the water-soluble P content in PAPR decreased with increasing Fe₂O₃ + Al₂O content in the PR used. Apparently, the presence of Fe₂O₃ + Al₂O₃ resulted in a reversion of some of the water-soluble P to citrate-soluble P and sometimes even to citrate-insoluble P.A short-term (6 weeks) greenhouse study was conducted to evaluate crop response to PAPRs and single superphosphate (SSP); maize, the test crop, was grown on an acid soil (pH 4.5)—Hartsells silt loam (Typic Hapludults). The agronomic effectiveness of PAPRs with respect to SSP (in terms of dry-matter yield of maize) decreased with increasing Fe₂O₃ + Al₂O₃ content in PRs. Phosphorus uptake by maize from PAPRs was found to correlate well with water solubility but not with citrate solubility. The results obtained in this study show that the detrimental effect of Fe₂O₃ + Al₂O₃ content on the solubility and P availability of PAPR should be considered when selecting a PR for PAPR production.     

Ethanol extraction of soybean oil

Extraction of soybean flakes with 90, 95, 98 and 100% ethanol resulted in more rapid lipid and less rapid non-lipid removal with the increasing ethanol concentrations. There was little difference in the quality of the oil produced by the different solvents. Protein content of the residual meal averaged 52.1%.     

High strength generation in cement pastes

Unusually high strengths have been generated in materials produced by employing “hot-pressing” techniques, and intermediate ranges of strengths have been achieved by applying high pressures at room temperature, to portland cement pastes. By pressing at ca. 250°C and 50, 000 psi strengths are as high as 95, 000 psi (compressive), and 9250 psi (indirect tensile). The hot-pressed materials are volume stable when immersed in water and subsequently evacuated. The microstructures of such materials are very compact, consisting of an intergrowth of dense hydrated cement “gel” surrounding residual unhydrated cement grain cores. The lowest porosity of the materials measured was approximately 1.8%, by far the closest approach to zero porosity or theoretical density yet achieved in cement pastes. The effect of microstructure and porosity are discussed, and high pressure techniques are compared with other methods of strength generation.     

Effects of Thermal Expansion Mismatch Stresses on th Room-Temperature Fracture of Boron Carbid

Calculation of apparent fracture energies (γ_a) using the applied failure stress and fractographically determined flaw sizes (C) in B₄ C shows γ_a decreasing with C , once C < 100 μm. This is attributed to increasing contributions of microstructural stresses (σ_i) due to thermal expansion anisotropy ( 1 × 10⁻⁶°C⁻¹). Extrapolation of this σ_i contribution to C ∼ G (the grain size) and calculation from maximum thermal expansion mismatch are in reasonable agreement. e.g., giving σ∼ 1000 MPa. Strength-mirror size data also show deviations at higher strengths-smaller mirror sizes consistent with both the occurrence and estimated level of such microstructural stress contributions to failure.