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This work is devoted to the visualization and evolution of κ1-phase particles in annealed proton exchange (PE) waveguides. It is well-known that the presence of κ1-phase particles in optical waveguides leads to an increase in their optical losses and instability of operation. It has been found that precipitated κ1-phase particles propagate through the whole waveguide depth and have perpendicular orientation to the surface of the lithium niobate crystal. These results are important for fast quality control of annealed PE waveguides. [ABSTRACT FROM AUTHOR]

Novel methods to probe and evaluate the mechanical properties of High entropy alloy are gaining popularity to accelerate the development of new material for structural application and for establishing the physics-based mechanical property models. Nanoindentation techniques are predominantly suitable for evaluating the properties of materials in which deformation volumes can be cautiously controlled, and indentation can be applied to probe the properties of specific phases or features present within the microstructure. The current investigation is based on the plastic deformation response of Eutectic High Entropy Alloy, AlCoCrFeNi2.1, using experimental and computational approaches. In this paper, the plastic deformation of eutectic high entropy alloy AlCoCrFeNi2.1 is investigated using nanoindentation over a broad range of strain rates at room temperature to probe the mechanical properties of Eutectic High Entropy Alloy, AlCoCrFeNi2.1 and also to understand its elasto-plastic behaviour of BCC and FCC phase present in the alloy. In order to capture the deformation mechanism of material under the tip of the nano-indenter as well as to predict the load variation with depth, molecular dynamic simulation is performed. A characteristic load-depth curve has also been generated from the developed model, which is in good agreement with the experimental one. These findings will lead to understanding the phase-specific contribution to bulk mechanical response of multicomponent alloys and aid in designing structural materials with high fracture toughness. [ABSTRACT FROM AUTHOR]

During hot forming of high-strength 7xxx series alloy, friction and galling often occur on the contact surface, degrade product surfaces quality, and affect severely by the process parameters, especially by load and speed. In the present paper, the effect of process parameters, namely applied load and sliding speed, on high-temperature friction and galling performance of AA7075 sheets has been determined using linear sliding tests at 350°C in simulated hot forming. The microscopic observations, i.e., scanning electron microscopy (SEM) and three-dimensional confocal scanning optical microscopy, were utilized to analyze hard phase distribution of the alloy as well as surface and sub-surface of the posttest specimens. A friction model was proposed to describe the friction mechanism. The results show that wear rate gradually decreased with increasing load and speed, attributing to the formed compacted oxide layer on the worn surface, which inhibited the rate of further attrition. Besides, for all test conditions, adhesion dominated the wear mechanism, and the compacted layer was damaged more serious due to more initiation of micro-cracks between hard phase and matrix and higher contact interface temperature at higher load and speed, thus the extent of adhesion is grievous resulting in a higher wear loss. [ABSTRACT FROM AUTHOR]

The structure of lanthanum nickelate (LNO) thin film electrodes prepared by chemical solution deposition has been investigated. Features of LNO microstructure have been studied using high-resolution transmission electron microscopy techniques, electron diffraction, and elemental mapping by energy dispersive X-ray analysis. Structure evolution of LNO after crystallization in the temperature range of 550 ÷ 800 °C has been visualized. Chemical and phase delamination within each sublayer was revealed in the LNO structure over the entire temperature range. Nanograins of Ni3O4 (С2/m), La2O3 (С2/m), LaNiO3 ( P m 3 ¯ m), and La2Ni2O5 (С2/m) phases were identified in the annealed LNO layer. [ABSTRACT FROM AUTHOR]

In this paper, a novel AM series Mg alloy developed through a stir casting process has been discussed. The current research utilizes an improved stir casting setup with a systemized inert facility. The effects of the processing parameters viz. stirring speed and holding temperature on microstructure and mechanical properties of the novel AM alloy (Mg-7 wt%Al-0.9 wt%Mn) have been investigated during the study. In addition, the study also attempts to highlight the adverse effect of higher values of processing parameter on porosity. The five output variables, such as Ultimate tensile strength (UTS), Yield strength (YS), Elastic modulus (E), Hardness, and Density (d), were measured for different combinations of processing parameters. The results showed an evident rise in the mechanical properties with the variation of stirring speed and holding temperature; the optimum values were attained at 250 rpm and 700°C. A significant enhancement in the Elastic modulus (24.3%) and hardness (16.21%) was witnessed vis-à-vis the existing AM series alloy. The improved properties of the novel material will make it a prospective candidate for industrial applications. [ABSTRACT FROM AUTHOR]

Gerald Schamess' writings have provided clinicians with a clear blueprint for structuring groups according to the developmental needs of each group. In this article, I highlight some of his ideas on children's groups, and apply them to a process group experience for graduate students. Topics such as roles, phase specific defenses, and how and when to intervene are described with clinical examples as illustration. [ABSTRACT FROM AUTHOR]

Machining brittle materials, such as silicon, is expensive and often causes detrimental damage, but a relatively new technique, termed microlaser-assisted machining (micro-LAM), improves the efficacy of the machining process using traditional single point diamond turning with simultaneous laser assistance. Prior work shows it provides a smooth surface finish and reduces the likelihood of fracture by increasing the ductility of the material during the machining process. However, the quality of the finish and the utility of the machined silicon depends on having good phase purity and low residual stresses. Using Raman microspectroscopy and a wide range of micro-LAM machining parameters the current work has shown that the technique can give excellent results in terms of low residual stress, high phase purity, and good relative crystallinity. However, poor choice of process parameters can be very detrimental leading to high residual stresses (over 400 MPa) and multiple silicon phases being present. [ABSTRACT FROM AUTHOR]

There is a growing body of research on network driven innovation. Based on seven case studies of regional innovation networks in tourism, this paper aims to develop a better understanding of the dynamics of their development. While innovation research emphasizes the complexity of the innovation process and its cyclic and iterative nature, network research describes the development of innovation networks mainly based on linear models. Inspired by Van de Ven, Polley, Garud, and Venkataraman’s [1999. The innovation journey. New York, NY: Oxford University Press] metaphor of a “journey”, this article develops the concept of the “innovation network journey” to describe both the designed and emergent development of networks working with innovation. The development processes are categorized into phases that may be repeated throughout the network lifespan, and crossroads that lead to the changed pace or path of the network journey. The paper contributes to the existing literature by new knowledge about how crossroads can be a part of the network journey and four main critical factors leading to crossroads, namely financing, management, organizing and shared activities. [ABSTRACT FROM AUTHOR]

The traditional mine planning framework employs a flawed approach in the design of ultimate pit limits and phases. Conventional methods arbitrarily confine the mine’s extraction schedule during the initial stages, detracting from its optimality before it is created. This work aims to provide a method by which a mine’s phase design is created from an optimal extraction schedule. The schedule-based approach to phase design yields implementable mining phases that mimic the initial raw optimal schedule from which it is based. An attempt to minimise the trade-off between mineability and value is inherent to the approach. [ABSTRACT FROM AUTHOR]

Polyvinylidene fluoride (PVDF) is a semicrystalline thermoplastic and electroactive polymer with piezoelectric and pyroelectric properties, thermal stability, elasticity, and chemical resistance. PVDF exits in five different phases (α, β, δ, γ, and ε-phase). Unique properties of this polymer enhances its use in chemical, biomedical, and electronic industries such as supercapacitors, transducers, actuators, and batteries. Carbon nanotube (CNT) is used as reinforcement to exploit full potential of PVDF in energy, electronics, and membrane technology. The nanofiller affects morphology, piezoelectric, pyroelectric, electrical, dielectric, thermal, and mechanical properties of PVDF-based nanocomposite. CNT content and chemical modification influence properties as well as application of PVDF. [ABSTRACT FROM AUTHOR]

The authors summarize the applications of transmission electron microscopy in the field of nanotechnology. Transmission electron microscopy (TEM) has represented as a very powerful instrument for studying and researching about the structure of nanomaterials in the material science world. The quantitative measures of particle size, grain size, size distribution, size homogeneity, lattice type, morphological information, crystallographic details, chemical composition of phases distribution, and parameters can obtain by transmission electron micrographs. So, TEM is the best technique for characterization of the nanomaterials such as nanoparticles and nanocomposites. Moreover, this study shows that electron diffraction pattern via the TEM is a perfect procedure for determining the structure of materials, including perfect crystals, defect structure, and phases. The study tries to show ability of TEM for characterization of nanomaterials. [ABSTRACT FROM PUBLISHER]

In an effort to detail the thermal variation of the bitumen microstructure, one sample of asphalt cement (CAP 30/45) was analyzed by atomic force microscopy before and after thermal treatment. Phase contrast and topography images showed that sample morphology is highly dependent on the thermal history of the sample. It can be observed that thermal treatment can lead either to asphaltene flocculation or to wax crystallization. In situ measurements indicated that, after thermal cycles, “bees” appear to be immersed in a lamellar structure that resembles a surface crystallization process. Conditions for the crystallization of the waxes as well as the stability of the “bee” are discussed. [ABSTRACT FROM PUBLISHER]

In the present article, influence of manganese on the size and shape of the precipitated TiC crystals by in-situ reaction with varying amounts of manganese in hypoeutectoid steel are presented. Manganese was added up to 6.0% in steps of 1.5%, titanium was fixed at 4%, and carbon at 1.84%. The obtained specimens were examined by using optical, scanning electron microscope (SEM), and X-ray diffraction (XRD) analysis. Tensile properties were evaluated using the ASTM E8 M standard. The microstructure results showed that the in-situ TiC carbides are homogeneously distributed in the metal matrix. Based on the microstructure and XRD pattern, in-situ TiC carbides were identified. The precipitated in-situ TiC in molten Fe-Mn-C alloy is explained by constructing three-dimensional iron rich Fe-Mn-TiC phase diagram. In Fe-Mn-TiC composite, varying manganese content increases the Young's modulus, ultimate tensile strength, and percentage elongation. [ABSTRACT FROM PUBLISHER]

13/4 low carbon martensitic stainless steel is conventionally used for turbine blades in hydroelectric power plants. Due to silt erosion and cavitation, heavy damage often occurs in this material. In order to enhance the life of hydro-turbine components, repair welding is needed. Selection of proper welding parameters during repair welding is therefore essential in order to control any possible deterioration of its mechanical properties. This work deals with heat affected zone (HAZ) simulation of 13/4 martensitic stainless steel using a thermomechanical simulator, Gleeble® 3800. Assessment of Charpy impact toughness, tensile properties, and hardness of HAZ simulated specimens is done. Peak temperatures of 1,000°C, 1,200°C, and 1,325°C and preheat temperatures of 30°C and 121°C are used. High impact toughness (52.8 J) and ductility (19.3%) is observed in steel specimens simulated with peak temperature of 1,000°C along with 121°C preheat temperature. The observed results are explained based on the microstructural changes resulting from different welding parameters. [ABSTRACT FROM AUTHOR]

Ferromagnetic Al2O3-based cermets characterized by homogeneous dispersion of Co-Ni alloy particles were successfully prepared via thermal explosion. The differential scanning calorimeter (DSC) analysis was employed to investigate the reaction process of Al-CoO-NiO system. X-ray diffraction (XRD) and scanning electron microscope (SEM) analysis on water-quenched samples were carried out for phase identification and microstructure observation, respectively. The results show that a solid state reaction between Al and CoO (NiO) occurs at about 939 K and the reaction of Al melt and CoO (NiO) leads to the ignition of thermal explosion. The Al2O3 initially added into the compact cannot only prevent the as-synthesized product from splashing under high combustion temperature, but also react with CoO (NiO) to form intermediate spinel phase (Co, Ni)Al2O4. The measured saturation magnetization and coercive force of synthesized ferromagnetic (Co, Ni)-Al2O3 cermets are 29 emu/g and 31 Oe, respectively. [ABSTRACT FROM AUTHOR]

The second-order thermodynamic perturbation theory formulation of Barker and Henderson is used to derive the equation of state of the triangle-well fluid. This is combined with the rational function approximation to the radial distribution function of the hard-sphere fluid. Results are obtained for the critical parameters and the liquid–vapour coexistence curve for various values of the range of the potential. A comparison with available simulation data is presented. [ABSTRACT FROM PUBLISHER]

In the present study, the tribological behavior of NiCrB coating at various loading conditions was investigated. At lower load, evolution of amorphous α-Fe2O3, Fe3O4, and Cr2O3 phases were observed in wear scars, whereas at higher loading conditions the growth of these phases was prominent. Among the different phases formed, the crystalline Cr2O3 phase dominated at higher loading conditions. Transformation of these phases occurred with a change in loading conditions, which is attributed to the growth and oxidation of oxide scales. The morphology of wear scars was found to change with a change in loading conditions. These changes significantly damaged the oxide scale by cracking and fretting at higher loading conditions. Evolution of amorphous and crystalline Cr2O3 gives rise to a coefficient of friction value comparable to that of the lubricant phase of α-Fe2O3. [ABSTRACT FROM AUTHOR]

Silicon carbide coatings have been deposited by r.f. magnetron sputtering on AISI 304LN stainless steel at four different substrate temperatures. At the lowest substrate temperature of 300°C, the film was amorphous whereas at a substrate temperature of 600°C a crystalline SiC phase was obtained. However, at substrate temperature of 800°C, the films were amorphous again. The tribological properties of the coatings were also found to change with substrate temperature. The coefficient of friction was found to be low for the crystalline films. Such a low value of coefficient of friction is indicative of superior wear resistance. A higher coating thickness enhanced the tribological properties while any surface roughness of the substrate and coating was found to degrade these properties. Micro-Raman spectra of the films varied with substrate temperature. Some phases were found to disappear and new phases were observed in the wear track with progressive sliding. [ABSTRACT FROM AUTHOR]

This article has its origins in several complementary sources: the personal coaching experiences of both myself and my co-authors in 14 books on coaching and mentoring; the experiences of coaches, who I have supervised; and observation of coaches in real plays within coach assessment centres (robust, validated processes for evaluating the competence and 'fit' of executive coaches for large-scale users of external coaches). The assessment centre approach is primarily a European and South African phenomenon currently, but multinational companies that have experienced it have voiced intentions to bring it to all territories, where they have a significant spend on executive coaching. [ABSTRACT FROM AUTHOR]

This paper investigates the process of regaining meaning after spinal cord injury. The study had a longitudinal case study design, in which twelve patients suffering from sudden damage of the spinal cord were followed by field observation and narrative interviews. Data was analysed from a phenomenological-hermeneutic perspective. Seventy-eight interviews were conducted over a two-year period. The main finding was that the process of regaining meaning after a spinal cord injury proceeded through six phases; Surviving physically and regaining vitality, Moving back to life where possibilities present themselves, Working with progress to pursue possibilities, Fading progress narrow possibilities down, Exploiting limited possibilities, and Living a life with qualities despite limitations. The core was the patient's imagination of a future worth going for, and of whether the present situation made this future seem possible. The balance between present and future concerns was very vulnerable to influence from the environment. The paper illuminates the delicacy of the situation and of how minor elements may disturb the balance and hence upset the situation. [ABSTRACT FROM AUTHOR]

The article discusses a study on the various methods to analyze the volleyball score sheet. The author stated that the score sheet is the document that reflects what occurs during the match and is filled out by the scorekeeper during the match. He emphasized that information obtained by score sheet analysis will let coaches establish the criteria and goals of his/her team in practice and in competition.

The recent frequency and intensity of crises and disasters affecting the tourism industry has resulted in a growing body of research into their causes, effects and management, as the bibliographies of the ensuing papers catalogue. To date, most papers and collections of research have taken a broad approach, describing the origins of a particular event which triggered a tourism crises, followed by an examination of the differential effects of the crisis on local residents, staff', tourists and tourism organizations or the environment and infrastructure. They have also discussed rescue efforts and the complexity of management tasks in the immediate aftermath of an event, often pointing to the need for preplanning to mitigate the consequences of any future disaster. Other researchers have contributed directly to the academic debate about how to theorise tourism crisis management, often by drawing on the wider crisis management literature. The present collection of research differs in that it focuses on one phase of the tasks which managers face after the immediate consequences of a crisis have been dealt with. This phase addresses the question of how to rebuild the market for a tourism service or a destination which has experienced a significant catastrophe, and how to learn from the experience in planning for future crisis response strategies. It is suggested in this paper that the challenges are actually more varied and complex than is implied by the suggestion, found in much of the literature, that the task is about 'restoring normality.' The chaos and complexity experienced in the aftermath of a crisis raise general issues of how organizations learn and adapt to change. [ABSTRACT FROM AUTHOR]

The smectic liquid crystals can exhibit the sequence of phase transitions from the untilted SmA phase to the ferroelectric tilted SmC* phase and (or) to the different hexatic phases. Within the phenomenological model the properties of possible phase transitions are discussed. In particular, it is shown that in the transition region between the phases SmB*hex and SmI*, and between the phases SmA and SmI*, an incommensurate structure should exist. [ABSTRACT FROM AUTHOR]

This article provides an overview of the evolution of the ‘‘drug court’’ concept in the United States, from its introduction in Miami in 1989 to the over 1300 programs now operating or being planned in every state. The topics covered will include: a) a description of the drug court process and services compared with the traditional adjudication process; b) principal findings to date, including what has been learned and what still needs to be studied; c) implications of the drug court concept for other aspects of the U.S. justice system; and d) unresolved critical issues that will impact upon its future development. [ABSTRACT FROM AUTHOR]

We investigated the orientation of quick phases (QPs) of vestibularly-induced eye movements in rabbits in response to ''off-vertical'' sinusoidal vestibular stimulation. We also examined the possible role of the cerebellar nodulus and ventral uvula in controlling QP spatial orientation and modification. During ''off-vertical'' vestibular stimulation QPs remained aligned with the earth's horizontal plane, while the slow phases (SPs) were aligned with the plane of vestibular stimulation. This suggests that QPs are coded in gravito-inertial coordinates and SPs in head coordinates. When rabbits were oscillated in the light (20° peak-to-peak; 0.2 Hz) about an ''off-vertical'' axis for 2 h, the QPs changed their trajectory, abandoning the earth's horizontal plane to approach the plane of the stimulus. By contrast, in the absence of conjunctive optokinetic stimulation, QPs remained fixed in the earth's horizontal plane even after 2 h of ''off-vertical'' stimulation. The conjunctive combination of optokinetic and vestibular stimulation caused QPs to change their plane of rotation. After lesion of the nodulus-uvula the ability of rabbits to reorient QPs during conjoint vestibular-optokinetic stimulation was maintained. We conclude that the space orientation and adaptation of QPs do not require cerebellar control. [ABSTRACT FROM AUTHOR]

The influence of neck and leg proprioceptive inputs on optokinetic-induced quick phases was studied in humans. Ten subjects received unidirectional horizontal optokinetic stimulation (10-20°/s) during sinusoidal neck, leg and combined neck + leg proprioceptive stimulation. The optokinetic reflex was measured by electro-oculography. Neck stimulation induced a shift in the nystagmus beating field in the opposite direction to body movement (gain 0.3-0.4, phase 140-180°). The beating field shift resulted totally from the amplitude and frequency modulation of optokinetic quick phases, as slow phases were not affected. Leg proprioceptive stimulation induced a similar effect, but the phase of the response lagged by ≈90° compared with that of neck response. With combined neck + leg stimulation, the amplitude of the effect was a sum of the separate effects, but the phase coincided with that of the leg response. This suggests that neck and leg proprioceptive signals do not add linearly and that the leg signal determines the time of the response. [ABSTRACT FROM AUTHOR]

The present research analysed on chronic animals the functional recovery of eye motility after impairment of the proprioceptive input at the level of the semilunar ganglion. The horizontal vestibulo-ocular reflex (HVOR) was recorded in normal pigmented rabbits before and after a partial electrolytic lesion of the semilunar ganglion. The recordings were repeated daily for 8-10 days to evaluate the recovery. Immediately after the lesion, as previously observed, HVOR slow phases were unaffected, while quick phases (QPs) showed a reduction in peak velocity and a deviation of trajectories from the horizontal plane. QP peak velocity was almost completely restored within 3-5 days, while trajectory deviation was not corrected during the observation period. Furthermore, in some animals, the variability of trajectories showed, starting from days 3-5, a progressive increase that led to a greater spatial disorganization. A process of lesion-induced plasticity takes place, but only the velocity of QPs can be recovered rapidly, while the QP trajectory impairment does not appear to be compensated substantially, which underlines a determinant role in the control of QP spatial orientation exerted by EOM proprioceptive signals. [ABSTRACT FROM AUTHOR]

In the frequency analysis of several time series observed simultaneously, it is often necessary to adapt classical results of linear models and multiple regression to situations involving complex-valued variates. Given a real-valued stochastic time series, Y(t), and a suitable vector-valued fixed series, X(t), with components X[sub j](t) (j = 1, 2, . . . , r, t = 0, +/- 1, . . .), it may be of interest to assess the effect, in the frequency domain, of each component series of X(t) on the behavior of Y(t). If values of Y(t) and X(t) are made available for t = 0, 1, . . . , T - 1, then under certain conditions and for large T at frequency it the finite Fourier transform of Y(t) is approximately linearly related to the finite Fourier transform of X(t) through a complex-valued vector A(it). In an asymptotic sense, A(it), with entries A[sub j](lambda) (j = 1, 2, . . . , r), may be interpreted as a vector of complex regression coefficients of Y(t) on X(t) at frequency it. The amount of amplification and phase shift by which the X[sub l](t) series must be modified in order to give an optimum fit, on average, to the Y(t) series at frequency it is, therefore, determined by the real-valued gain, G[sub j](lambda) = [A[sub j](lambda)], and phase, phi[sub j](lambda) = arg A[sub j](lambda), respectively, of Y(t) over X[sub j](t). After estimating A[sub j](lambda), and also G[sub j](lambda) and phi[sub j](lambda), using results from multiple regression analysis adapted to complex-valued variates, a gain plot and a phase plot can be made for each j = 1, 2, . . . , r, with appropriate confidence regions drawn on the plot at each frequency it to assess the degree of association between Y(t) and the X[sub j](t) series. In this article new asymptotic simultaneous confidence regions for gains and phases... [ABSTRACT FROM AUTHOR]

The cross-spectral phases between velocity components at two heights are analyzed from observations at the Høvsøre test site and from the field experiments under the Cooperative Atmosphere-Surface Exchange Study in 1999. These phases represent the degree to which turbulence sensed at one height leads (or lags) in time the turbulence sensed at the other height. The phase angle of the cross-wind component is observed to be significantly greater than the phase for the along-wind component, which in turn is greater than the phase for the vertical component. The cross-wind and along-wind phases increase with stream-wise wavenumber and vertical separation distance, but there is no significant change in the phase angle of vertical velocity, which remains close to zero. The phases are also calculated using a rapid distortion theory model and large-eddy simulation. The results from the models show similar order in phasing, but the slopes of the phase curves are slightly different from the observations, especially for low wavenumbers. [ABSTRACT FROM AUTHOR]