Contextual Sensitivity in Grounded Theory: The Role of Pilot Studies

Grounded Theory is an established methodological approach for context specific inductive theory building. The grounded nature of the methodology refers to these specific contexts from which emergent propositions are drawn. Thus, any grounded theory study requires not only theoretical sensitivity, but also a good insight on how to design the research in the human activity systems to be studied. The lack of this insight may result in inefficient theoretical sampling or even erroneous purposeful sampling. These problems would not necessarily be critical, as it could be argued that through the elliptical process that characterizes grounded theory, remedial loops would always bring the researcher to the core of the theory. However, these elliptical remedial processes can take very long periods of time and result in catastrophic delays in research projects. As a strategy, this paper discusses, contrasts and compares the use of pilot studies in four different grounded theory projects. Each pilot brought different insights about the context, resulting in changes of focus, guidance to improve data collection instruments and informing theoretical sampling. Additionally, as all four projects were undertaken by researchers with little experience of inductive approaches in general and grounded theory in particular, the pilot studies also served the purpose of training in interviewing, relating to interviewees, memoing, constant comparison and coding. This last outcome of the pilot study was actually not planned initially, but revealed itself to be a crucial success factor in the running of the projects. The paper concludes with a theoretical proposition for the concept of contextual sensitivity and for the inclusion of the pilot study in grounded theory research designs

Diode laser modification of ceramic material surface properties for improved wettability and adhesion

To date, very little work has been published with regard specifically to the use of lasers for modifying the surface properties of materials in order to improve their wettability and adhesion characteristics. Using a 60 W high power diode laser (HPDL) the effects of HPDL radiation on the wettability and adhesion characteristics of certain ceramic materials have been determined. It was found that laser treatment of the materials surfaces’ modified the surface energy and accordingly, wetting experiments, by the sessile drop technique using a variety of test liquids, revealed that laser treatment of the range of ceramic materials surfaces resulted in a decrease in the contact angles. The work shows clearly that laser radiation can be used to alter the wetting and adhesion characteristics of a number of ceramic materials by means of changing the surface energy

Influence of skew and cross-coupling on flux-weakening performance of permanent-magnet brushless AC machines

A method is proposed for predicting the flux-weakening performance of permanent-magnet (PM) brushless ac machines accounting for skew and d-q axis cross-coupling. The method is based on a d-q-axis flux-linkage model, a hybrid 2-D finite-element (FE)-analytical method being used to predict the d- and q-axis inductances. However, it only requires 2-D FE analysis of the magnetic field distribution over a cross section of the machine. The developed method is used to predict the torque-speed characteristic of an interior PM brushless ac machine with one stator slot-pitch skew. This is compared with predictions from a direct FE analysis of the machine and validated by measurements

The Evolution of Ablation Area Induced by Femtosecond Laser

AbstractSurface damage morphologies were studied by irradiating with pulses (fluence of 1.13J/cm2) in succession. Investigation the dependence of the ablation regions on the number of the laser pulses, a silicon(100) plate was irradiated by the femtosecond laser in the range of 50 to 1000 pulse, with the fluence of 1.13J/cm2. The ablation regions had been divided into several parts, which depend on the number of pulses. The formation of columnar structure was discussed also

High power diode laser modification of the wettability characteristics of an Al2O3/SiO2 based oxide compound for improved enamelling

High power diode laser (HPDL) surface melting of a thin layer of an amalgamated Al2O3/SiO2 oxide compound (AOC) resulted in significant changes in the wettability characteristics of the material. This behaviour was identified as being primarily due to: (i) the polar component of the AOC surface energy increasing after laser melting from 2.0 to 16.2 mJm-2, (ii) the surface roughness of the AOC decreasing from an Ra value of 25.9 to 6.3 μm after laser melting and (iii) the relative surface oxygen content of the AOC increasing by 36% after laser melting. HPDL melting was consequently identified as affecting a decrease in the enamel contact angle from 1180 prior to laser melting to 330 after laser melting; thus allowing the vitreous enamel to wet the AOC surface. The effective melt depth for such modifications was measured as being from 50 to 125 μm. The morphological, microstructural and wetting characteristics of the AOC were determined using optical microscopy, scanning electron microscopy, energy disperse X-ray analysis, X-ray diffraction techniques and wetting experiments by the sessile drop technique. The work has shown that laser radiation can be used to alter the wetting characteristics of the AOC only when surface melting occurs

Analisis Framing Pemberitaan Kasus Dugaan Korupsi dan Gaya Hidup Mewah Gubernur Ratu Atut Chosiyah pada “Koran Tempo”

Modus korupsi sesungguhnya merupakan suatu manipulasi jabatan publik untuk keuntungan pribadi. Mereka menggunakan kewenangan menentukan kebijakan publik semata demi kepentingan sendiri. Peran KPK (Komisi Pemberantasan Korupsi) dan BPK ( Badan Pemeriksa Keuangan) dalam hal ini sangat berpengaruh untuk menghentikan laju pertumbuhan korupsi.Penelitian ini dilakukan untuk mengetahui pembingkaian (framing) berita koran Tempo terhadap kasus korupsi yang dilakukan oleh pejabat wanita terkait kasus dugaan korupsi dan gaya hidup mewah Ratu Atut Chosiyah. Dugaan kasus korupsi Ratu Atut banyak dimuat dalam media cetak maupun media televisi. Tempo terkenal keras pada kasus yang mengindikasi adanya praktik korupsi dan melibatkan kepentingan publik yang besar termasuk pejabat dan aparatur Negara. Tempo hingga kini mampu meliput beberapa kasus Atut baik dalam kasus korupsi maupun gaya hidup mewah Atut. Salah satu metode penelitian yang mampu menganalisis bagaimana realitas itu dibentuk dan dikonstruksi oleh media adalah analisis framing. Peneliti menggunakan analisa Framing yang diperkenalkan oleh Pan dan Kosicki. Obyek penelitian adalah pemberitaan kasus dugaan korupsi dan gaya hidup mewah Gubernur Ratu Atut Chosiyah yang muncul pada koran Tempodari tanggal 5 Okober 2013 sampai 13 November 2013.Hasil penelitian menunjukkan bahwa koran Tempo memberikan gambaran pemberitaan dengan menunjukan struktur Sintaksis, Skrip, Tematik, Dan Retoris. Struktr retoris dalam koran Tempo tampak menonjol karena wartawan koran Tempo banyak menggunakan istilah, leksikon, idiom, bahkan gambar karikatur yang dapat menarik perhatian khalayak. Koran Tempo terkenal dengan gaya pemberitaan yang kritis dan tajam serta memiliki volume dan frekuensi berita yang lengkap karena mampu memuat lebih dari satu pemberitaan dengan kasus yang sama dalam satu edisi. Koran Tempo dalam menuliskan pemberitaan tetap mengedepankan objektivitas dan netralitas, karena wartawan Tempo selalu menjaga agar sebuah karya tetap bermutu tinggi dan berpegang teguh pada kode etik. Nilai etika dan pilihan moral pada Tempo sesuai dengan visi Koran Tempo.Redaksi koran Tempo sebagai Perusahaan yang produknya informasi , diharapkan selalu menjaga obyektivitas dalam menyampaikan pemberitaan dengan memperbanyak sumber berita dan terus menerus meningkatkan apresiasi terhadap ide-ide baru, bahasa, dan tampilan visual yang baik sehinggs dapat menampilkan sebuah informasi yang bermutu tinggi dan layak dikonsumsi masyarakat

Synaptic Mitochondria Are Critical for Mobilization of Reserve Pool Vesicles at Drosophila Neuromuscular Junctions

SummaryIn a forward screen for genes affecting neurotransmission in Drosophila, we identified mutations in dynamin-related protein (drp1). DRP1 is required for proper cellular distribution of mitochondria, and in mutant neurons, mitochondria are largely absent from synapses, thus providing a genetic tool to assess the role of mitochondria at synapses. Although resting Ca2+ is elevated at drp1 NMJs, basal synaptic properties are barely affected. However, during intense stimulation, mutants fail to maintain normal neurotransmission. Surprisingly, FM1-43 labeling indicates normal exo- and endocytosis, but a specific inability to mobilize reserve pool vesicles, which is partially rescued by exogenous ATP. Using a variety of drugs, we provide evidence that reserve pool recruitment depends on mitochondrial ATP production downstream of PKA signaling and that mitochondrial ATP limits myosin-propelled mobilization of reserve pool vesicles. Our data suggest a specific role for mitochondria in regulating synaptic strength

Large-scale impact of CO2 storage in deep saline aquifers: A sensitivity study on pressure response in stratified systems

Large volumes of CO{sub 2} captured from carbon emitters (such as coal-fired power plants) may be stored in deep saline aquifers as a means of mitigating climate change. Storing these additional fluids may cause pressure changes and displacement of native brines, affecting subsurface volumes that can be significantly larger than the CO{sub 2} plume itself. This study aimed at determining the three-dimensional region of influence during/after injection of CO{sub 2} and evaluating the possible implications for shallow groundwater resources, with particular focus on the effects of interlayer communication through low-permeability seals. To address these issues quantitatively, we conducted numerical simulations that provide a basic understanding of the large-scale flow and pressure conditions in response to industrial-scale CO{sub 2} injection into a laterally open saline aquifer. The model domain included an idealized multilayered groundwater system, with a sequence of aquifers and aquitards (sealing units) extending from the deep saline storage formation to the uppermost freshwater aquifer. Both the local CO{sub 2}-brine flow around the single injection site and the single-phase water flow (with salinity changes) in the region away from the CO{sub 2} plume were simulated. Our simulation results indicate considerable pressure buildup in the storage formation more than 100 km away from the injection zone, whereas the lateral distance migration of brine is rather small. In the vertical direction, the pressure perturbation from CO{sub 2} storage may reach shallow groundwater resources only if the deep storage formation communicates with the shallow aquifers through sealing units of relatively high permeabilities (higher than 10 x 18 m{sup 2}). Vertical brine migration through a sequence of layers into shallow groundwater bodies is extremely unlikely. Overall, large-scale pressure changes appear to be of more concern to groundwater resources than changes in water quality caused by the migration of displaced saline water

Nonlinear low frequency gravity waves in a water-filled cylindrical vessel subjected to high frequency excitations

In the experiments of a water storage cylindrical shell, excited by a horizontal external force of sufficient large amplitude and high frequency, it has been observed that gravity water waves of low frequencies may be generated. This paper intends to investigate this phenomenon in order to reveal its mechanism. Considering nonlinear fluid–structure interactions, we derive the governing equations and the numerical equations describing the dynamics of the system, using a variational principle. Following the developed generalized equations, a four-mode approximation model is proposed with which an experimental case example is studied. Numerical calculation and spectrum analysis demonstrate that an external excitation with sufficient large amplitude and high frequency can produce gravity water waves with lower frequencies. The excitation magnitude and frequencies required for onset of the gravity waves are found based on the model. Transitions betweendifferent gravity waves are also revealed through the numerical analysis. The findings developed by this method are validated by available experimental observations

Fast colon centreline calculation using optimised 3D topological thinning

Topological thinning can be used to accurately identify the central path through a computer model of the colon generated using computed tomography colonography. The central path can subsequently be used to simplify the task of navigation within the colon model. Unfortunately standard topological thinning is an extremely inefficient process. We present an optimised version of topological thinning that significantly improves the performance of centreline calculation without compromising the accuracy of the result. This is achieved by using lookup tables to reduce the computational burden associated with the thinning process