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211.
Examined the impact of personal therapy on the professional and personal development of psychotherapists through in-depth interviews with 5 psychoanalytically oriented psychotherapists (aged 40–50 yrs). An adaptation of the method of consensual qualitative coding was used to study the narrative accounts of therapy experiences leading to the identification 6 domains: (1) importance of personal therapy for therapists; (2) impacts on the professional self: identity; (3) impacts or one's being in the session: process; (4) experiences in previous and current therapy; (5) self in relation to the personal therapists; and (6) mutual and unique influences of didactic learning, supervision, and personal therapy. The authors found that personal therapy is perceived not only as an essential part of the training phase, but as playing an important role in the therapist's ongoing process of individuation and in the development of the ability to use the self, to achieve moment-to-moment authentic relatedness with one's clients. The domains and categories are appended. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
212.
On Construction of Virtual Backbone in Wireless Ad Hoc Networks with Unidirectional Links 总被引:1,自引:0,他引:1
Since there is no fixed infrastructure in wireless ad hoc networks , virtual backbone has been proposed as the routing infrastructure to alleviate the broadcasting storm problem. The virtual backbone construction has been studied extensively in {em undirected} graphs, especially in unit disk graphs, in which each node has the same transmission range. In practice, however, transmission ranges of all nodes are not necessarily equal. In this paper, we model such a network as a disk graph, where unidirectional links are considered. To study the virtual backbone construction in disk graphs, we consider two problems: Strongly Connected Dominating Set (SCDS) and Strongly Connected Dominating and Absorbing Set (SCDAS). We propose a constant approximation algorithm and discuss its improvements for the SCDS problem . We also propose a heuristic for the SCDAS problem. Through extensive simulations, we verify our theoretical analysis and also demonstrate that the SCDS can be extended to form an SCDAS with marginal extra overhead. 相似文献
213.
Jianwu Yu Hong Luo Yingying Zhang Thai V. Nguyen Xiaomo Jiang Junzhi Hu 《Journal of the American Ceramic Society》2019,102(11):6606-6617
Compression creep tests (CCTs) have been widely used in phenomenological characterization of viscoelastic materials such as glasses. However, disturbed by specimen-tool interface friction, the real stress-strain data regarding the pure viscoelastic deformation are frequently misestimated in conventional CCTs, causing decreased accuracies of the derived viscoelastic parameters. This study proposes a comprehensive CCT-based approach to develop a viscoelastic model with weakened frictional disturbance and enhanced predictive accuracy. An integrated calculation procedure is first built to mathematically characterize the frictional and viscoelastic behaviors of glass during compression. Uniaxial CCTs of a typical borosilicate glass (L-BAL42) are then performed at varied frictional conditions. The quantified coefficients of interface friction indicate that a minor frictional disturbance is achieved when Nickel foils are used as interfacial layers, whereby a more realistic viscoelastic constitutive relation of the glass is derived. The obtained frictional and viscoelastic constants are further incorporated into computational modeling of the CCT and precision molding processes. The demonstrated consistencies between the simulated and measured results (creep displacement and molding force) suggest that, by technically slashing the interface friction and theoretically correcting the friction-involved stress in CCTs, the frictional disturbance to experimental stress-strain data can be effectively weakened, and a viscoelastic model of enhanced predictive accuracy can be thus developed. 相似文献
214.
T. Nguyen‐Thoi P. Phung‐Van H. Nguyen‐Xuan C. Thai‐Hoang 《International journal for numerical methods in engineering》2012,91(7):705-741
The cell‐based strain smoothing technique is combined with discrete shear gap method using three‐node triangular elements to give a so‐called cell‐based smoothed discrete shear gap method (CS‐DSG3) for static and free vibration analyses of Reissner–Mindlin plates. In the process of formulating the system stiffness matrix of the CS‐DSG3, each triangular element will be divided into three subtriangles, and in each subtriangle, the stabilized discrete shear gap method is used to compute the strains and to avoid the transverse shear locking. Then the strain smoothing technique on whole the triangular element is used to smooth the strains on these three subtriangles. The numerical examples demonstrated that the CS‐DSG3 is free of shear locking, passes the patch test, and shows four superior properties such as: (1) being a strong competitor to many existing three‐node triangular plate elements in the static analysis; (2) can give high accurate solutions for problems with skew geometries in the static analysis; (3) can give high accurate solutions in free vibration analysis; and (4) can provide accurately the values of high frequencies of plates by using only coarse meshes. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
215.
This paper presents new features and a novel decision-making system for automated classification of power quality disturbances. The most common types of disturbances including flickers, harmonics, impulses, notches, outages, sags, swells, and switching transients are studied. Disturbances consisting of both sag and harmonic, or both swell and harmonic are also considered. It is assumed that the analyzed waveforms are available in sampled form. The signal processing techniques utilized to extract the distinctive features of the waveforms are Fourier and S-transform. A new method based on binary feature matrix is designed for making a decision regarding the disturbance type. Evaluation studies for verifying the accuracy of the method are presented. 相似文献
216.
The electrophoresis of proteins was investigated using poly(dimethylsiloxane) (PDMS) microfluidic chips whose surfaces were modified with polyacrylamide through atom-transfer radical polymerization. PDMS microchips were made using a glass replica to mold channels 10 microm high and 30 microm wide, with a T-intersection. The surface modification of the channels involved surface oxidation, followed by the formation of a self-assembled monolayer of benzyl chloride initiators, and then atom-transfer radical polymerization to grow a thin layer of covalently bonded polyacrylamide. The channels filled spontaneously with aqueous buffer due to the hydrophilicity of the coating. The resistance to protein adsorption was studied by open-channel electrophoresis for bovine serum albumin labeled with fluorophor. A plate height of 30 microm, corresponding to an efficiency of 33 000 plates/m, was obtained for field strengths from 18 to 889 V/cm. The lack of dependence of plate height on field strength indicates that there is no detectable contribution to broadening from adsorption. A 2- to 3-fold larger plate height was obtained for electrophoresis in a 50-cm polyacrylamide-coated silica capillary, and the shape of the electropherogram indicated the efficiency is limited by a distribution of species. The commercial capillary exhibited both reversible and irreversible adsorption of protein, whereas the PDMS microchip exhibited neither. A separation of lysozyme and cytochrome c in 35 s was demonstrated for the PDMS microchip. 相似文献
217.
218.
The use of hydraulic systems in industrial applications has become widespread due to their efficiency advantages. In recent years, hybrid actuation system, which combines electric and hydraulic technology in a compact unit, can be adapted to a wide variety of force, speed and torque requirements. Moreover, the hybrid actuation system has dealt with the energy consumption and noise problem existed in the conventional hydraulic system. Mini motion package (MMP) is one type of the new low cost hybrid actuator. This MMP is considered as a novel linear actuator with various applications such as robotics, automation, plastic injection-molding and metal forming technology. However, this efficiency gain is often accompanied by a degradation of system stability and control problems. In this paper, to maintain robust performance requirement, tracking performance specification, and disturbance attenuation requirement, the design of a robust force controller for the new hybrid actuator using quantitative feedback theory (QFT) is presented. A family of plants model for MMP is obtained from experimental frequency responses of the system in the presence of significant uncertainty. Experimental results show that highly robust force tracking by the MMP actuator could be achieved even if the stiffness of environment and set-point force change. In addition, it is understood that the new system has energy-saving effect even though it has almost the same response as that of valve controlled system. 相似文献
219.
Perovskite oxides like SrTiO3 at the nanoscale are of interest for emerging applications,including high-k dielectrics and sensors.However,their synthesis requires long calcination at the elevated temperature,which is a barrier of their application to flexible electronics.Here,an effective laser-assisted sol-gel method to patternably produce SrTiO3 nanoparticles (-100 nm) in selective areas on polyimide substrates (coated with ITO) is introduced.Importantly,the violet-laser power is just 1 W but sufficient to crystallize the material in a short period (a few seconds).Furthermore,developing a flexible device platform using carbon nanotubes (CNT) and SrTiO3 nanoparticles for detection of humidity changes at room temperature is proposed.The sensor platform has both capacitive and resistive sensing abilities.The resistive mode with a lower power usage (about 0.2 μW) is suitable for long monitoring of humidity in the range of 2% RH and above.The capacitive mode with higher sensitivity,faster response/recovery time (1-3 min),and lower detection limit (0.5% RH) can be used for calibration purposes.The performance of the flexible sensor is still maintained after 5000 bending cycles at 1.5-cm radius.Altogether,our synthesis method and the flexible sensor show chances for mass-producing perovskite oxides at low cost for wearable electronics. 相似文献
220.
Kyoung Kwan Ahn Nguyen Huynh Thai Chau Dinh Quang Truong 《Journal of Mechanical Science and Technology》2007,21(12):2048-2058
The use of hydraulic systems in industrial applications has become widespread due to their advantages in efficiency. In recent
years, hybrid actuation systems, which combine electric and hydraulic technology into a compact unit, have been adapted to
a wide variety of force, speed and torque requirements. A hybrid actuation system resolves energy consumption and noise problems
characteristic of conventional hydraulic systems. A new, low-cost hybrid actuator using a DC motor is considered to be a novel
linear actuator with various applications such as robotics, automation, plastic injection-molding, and metal forming technology.
However, this efficiency gain is often accompanied by a degradation of system stability and control problems. In this paper,
to satisfy robust performance requirements, tracking performance specifications, and disturbance attenuation requirements,
the design of a robust force controller for a new hybrid actuator using Quantitative Feedback Theory (QFT) is presented. A
family of plant models is obtained from measuring frequency responses of the system in the presence of significant uncertainty.
Experimental results show that the hybrid actuator can achieve highly robust force tracking even when environmental stiffness
set-point force varies. In addition, it is understood that the new system reduces energy use, even though its response is
similar to that of a valve-controlled system. 相似文献