Exploring the eradication of code smells: An empirical and theoretical perspective

This article has been made available through the Brunel Open Access Publishing Fund - Copyright @ 2010 Hindawi Publishing CorporationCode smells reflect code decay, and, as such, developers should seek to eradicate such smells through application of “deodorant” in the form of one or more refactorings. However, a relative lack of studies exploring code smells either theoretically or empirically when compared with literature on refactoring suggests that there are reasons why smell eradication is neither being applied in anger, nor the subject of significant research. In this paper, we present three studies as supporting evidence for this stance. The first is an analysis of a set of five, open-source Java systems in which we show very little tendency for smells to be eradicated by developers; the second is an empirical study of a subsystem of a proprietary, C# web-based application where practical problems arise in smell identification and the third, a theoretical enumeration of smell-related refactorings to suggest why smells may be left alone from an effort perspective. Key findings of the study were that first, smells requiring application of simple refactorings were eradicated in favour of smells requiring more complex refactorings; second, a wide range of conflicts and anomalies soon emerged when trying to identify smelly code; an interesting result with respect to comment lines was also observed. Finally, perceived (estimated) effort to eradicate a smell may be a key factor in explaining why smell eradication is avoided by developers. The study thus highlights the need for a clearer research strategy on the issue of code smells and all aspects of their identification and measurement.The research in this paper was supported by a grant from the UK Engineering and Physical Sciences Research Council (EPSRC) (Grant no: EP/G031126/1

Etude physicochimique de l’huile essentielle de Ruta Chalepensis L. de Tlemcen, Algérie

Ruta chalepensis L. (Rutacée), est une plante aromatique médicinale encore utilisée dans la médecine traditionnelle de nombreux pays comme laxatif, antiinflammatoire, analgésique, antipasmodique, abortif, antiépileptique, emménagogue et pour le traitement de pathologies cutanées. Des screening phytochimiques ont mis en évidence la présence de coumarines en sus d’alcaloïdes et ont donné la composition chimique de l’huile essentielle de la partie aérienne de la plante provenant de différents pays. Ce travail a porté sur la composition chimique de l’huile essentielle de la plante provenant de l’Algérie, qui n’a jamais fait l’objet de publication. Les analyses ont été réalisées par chromatographie en phase gazeuse (CG) et CG – spectrométrie de masse (SM). 20 composés représentant 64.66 - 93.99% de l’huile essentielle ont été identifiés et, comme composé majoritaire le 2-undécanone (20.40 - 82.74%). L’étude des variations du rendement, des propriétés physicochimiques et de lacomposition chimique de l’huile essentielle a été réalisée en fonction de la partie de la plante étudiée, la période et le lieu de cueillette de la plante. Les résultats ainsi obtenus ont montré l’extrême variabilité du rendement, des propriétés physicochimiques et de la composition.Mots-clés : Ruta chalepensis, huile essentielle, composition chimique, chromatographie en phase gazeuse, spectrométrie de masse, chemotype, 2- undécanone

The characteristics of a good teacher and how to become one

The need for good teachers and good teaching has been, and will continue to be researched into and identified. This paper discusses the qualities of good teachers in relation o classroom teaching. It introduces teaching as involving communication and interaction between teacher and the students, and describes the teacher as a motivator and facilitator of learning. The paper highlighted how to become a good teacher. It also offers suggestions how good teachers can be produced .It concludes that a good teacher or one, who want to be, should have all the general attributes and qualities of a good professional classroom teacher so that they can excel and have good and effective performance in the classroom.Keywords: Teacher, Students, Schools, Trait

Evolution of Superconductivity in Electron-Doped Cuprates: Magneto-Raman Spectroscopy

The electron-doped cuprates Pr_{2-x}Ce_xCuO_4 and Nd_{2-x}Ce_xCuO_4 have been studied by electronic Raman spectroscopy across the entire region of the superconducting (SC) phase diagram. The SC pairing strength is found to be consistent with a weak-coupling regime except in the under-doped region where we observe an in-gap collective mode at 4.5 k_{B}T_c while the maximum amplitude of the SC gap is ~8 k_{B}T_{c}. In the normal state, doped carriers divide into coherent quasi-particles (QPs) and carriers that remain incoherent. The coherent QPs mainly reside in the vicinity of (\pi/2, \pi/2) regions of the Brillouin zone (BZ). We find that only coherent QPs contribute to the superfluid density in the B_{2g} channel. The persistence of SC coherence peaks in the B_{2g} channel for all dopings implies that superconductivity is mainly governed by interactions between the hole-like coherent QPs in the vicinity of (\pi/2, \pi/2) regions of the BZ. We establish that superconductivity in the electron-doped cuprates occurs primarily due to pairing and condensation of hole-like carriers. We have also studied the excitations across the SC gap by Raman spectroscopy as a function of temperature (T) and magnetic field (H) for several different cerium dopings (x). Effective upper critical field lines H*_{c2}(T, x) at which the superfluid stiffness vanishes and H^{2\Delta}_{c2}(T, x) at which the SC gap amplitude is suppressed by field have been determined; H^{2\Delta}_{c2}(T, x) is larger than H*_{c2}(T, x) for all doping concentrations. The difference between the two quantities suggests the presence of phase fluctuations that increase for x< 0.15. It is found that the magnetic field suppresses the magnitude of the SC gap linearly at surprisingly small fields.Comment: 13 pages, 8 figures; submitted to Phys. Rev.

Surface thermal perturbations of the recent past at low latitudes ? inferences based on borehole temperature data from Eastern Brazil

International audienceBorehole temperature data from the eastern parts of Brazil has been examined in an attempt to extract information on surface thermal perturbations of the recent past at low latitudes. Forward models were employed in the analysis of temperature logs from 16 localities and, in addition, inverse modeling was carried out for data from 10 selected sites. The model results have allowed determination of the magnitude as well as the duration of ground surface temperature (GST) changes in three major geographic zones of Brazil. Prominent among such events are the warming episodes that occurred over much of the subtropical highland regions in the southeastern parts of Brazil. The present magnitude of GST changes in this region are in the range of 2 to 3.5°C but have had their beginning during the early decades of the 20th century. Nearly similar trends are also seen in temperature-depth profiles of bore holes in the subtropical humid zones of the interior and coastal areas of southern Brazil. The data from semi arid zones of northeast Brazil also indicate occurrence of surface warming events but the magnitudes are in the range of 1.4 to 2.2°C while the duration of the warming event is larger, extending back into the last decades of the 19th century. There are indications that changes in both climate and vegetation cover contribute to variations in GST. Thus the magnitudes of GST variations are relatively large in localities which have undergone changes in vegetation cover. Also there are indications that GST changes are practically insignificant in areas of tropical rain forest. Another important result emerging from model studies is that the climate was relatively cooler during the 17th and 18th centuries. The climate histories, deduced from geothermal data, are found to be consistent with results of available meteorological records in southern Brazil. Comparative studies also indicate that the magnitudes and duration of recent climate changes in southern and eastern Brazil are similar to those found in other continental areas such as North America, Asia and Europe

Design and implement WSN/IoT smart parking management system using microcontroller

With the dramatic expansion of new networks such as Wireless Sensor Network (WSN) and Internet-of-Things (IoT), tremendous opportunities have been emerged to incorporate such technologies for valuable tasks. One of these tasks is the smart car parking where there is an imperative demand to manage the parkings in various facilities which may help drivers to save their time. Several research studies have addressed this task using wide range of approaches. However, the energy consumption is still a serious concern. This paper proposes a smart car parking based on cloud-based approach along with variety of sensors. Passive Infrared Sensors (PIRs) have been used to sense the object motion. While Light Dependent Resistor (LDR) sensors have been utilized to sense the light of the parking alarm and display inmformation regarding the occupied and non-occupied parking lots. Finally, multi-micro controller of Arduino have been exploited in order to transmit the information collected to the server. Finally, a prototype Android application has been developed in order to recieve the infromation from the server. Results of simulation showed the efficacy of the proposed method

Microwave assisted K2CO3 palm shell activated carbon as sorbent for CO2 adsorption application

Carbon dioxide is believed to be a major greenhouse gas (GHG) that contributes to global warming. In this study, palm shells were used as a precursor to prepare CO2 activated carbon sorbents via carbonization, chemical impregnation with K2CO3 and microwave activation. Adsorption equilibrium data for CO2 adsorption on the porous carbon were obtained at different temperatures using static volumetric adsorption method. Langmuir, Freundlich, Sips and Toths models were used to correlate the experimental data. The CO2 adsorption capacity at 303.15, 343.15, 378.15 443.15 K and 1 bar on the sorbent was 2.71, 1.5, 0.77, 0.69 mmol/g respectively. Sips isotherm was found to have the best fit. The results indicated that the porous carbon sorbent prepared by carbonization and microwave K2CO3 assisted activation have good CO2 uptake. The porous carbons produced are therefore good candidates for CO2 adsorption applications

A Review Article: Free Radical and Replacement Synthetic Antioxidant by Natural Antioxidant

Free radical may be responsible of several pathophysiology disease for threatening human life, and they are produced from endogenous and exogenous sources. Using the balanced amount&nbsp; of nutritious diet lead to a good health, may be neutralizing or scavenging&nbsp; free radicals by antioxidants compounds. daily diet have large number of vitamin A, E and C, carotenoids, polyphenols, etc. as natural antioxidants, the main bases of them are fruits, cereals, vegetables, and beverages. Enzymatic and non-enzymatic antioxidant substances are two different kinds that lessen the reactions of free radicals. In order to protect itself from reactive oxygen species, the human body uses an enzyme antioxidant. The two kinds of non-enzymatic antioxidants are natural antioxidants and synthetic antioxidants. The aim of this review is to knowledge a reasons which causes the free radical and balance them by natural antioxidant constituents, and replacement synthetic antioxidant by natural antioxidant, due to daily diet have large amounts from natural antioxidants, and natural antioxidants more effective than synthetic antioxidants, in additional they occurrence in nature and more inexpensive